Increases in callus formation and mechanical strength of healing fractures in old rats treated with parathyroid hormone.

Andreassen TT, Fledelius C, Ejersted C, Oxlund H. Department of Connective Tissue Biology, Institute of Anatomy, University of Aarhus, Denmark. tta@ana.au.dk

Acta Orthop Scand. 2001 Jun;72(3):304-7.

We studied the effects of intermittent administration of parathyroid hormone (PTH(1-34)) on callus formation and mechanical strength of tibial fractures in 27-month-old rats after 3 and 8 weeks of healing. 200 microg PTH(1-34)/kg was administered daily during both periods of healing, and control animals with fractures were given vehicle. At 3 weeks, PTH treatment increased maximum load and external callus volume by 160% and 208%; at 8 weeks, by 270% and 135%. It also enhanced callus bone mineral content (BMC) by 190% and 388% (3 and 8 weeks). From week 3 to week 8, callus BMC increased by 60% in the vehicle-injected animals, and by 169% in the PTH-treated animals. In the contralateral intact tibia, PTH treatment increased BMC by 18% and 21% (3 and 8 weeks). No differences in body weight were found between the vehicle-injected and the PTH-treated animals during the experiment. In conclusion, PTH treatment enhances fracture strength, callus volume and callus BMC after 3 and 8 weeks of healing.

The role of zinc in wound healing.

Andrews M, Gallagher-Allred C. Geriatric and Long Term Care Services, Ross Products Division, Abbott Laboratories, Columbus, OH, USA.

Adv Wound Care 1999 Apr;12(3):137-8

Zinc deficiency has been associated with delayed wound healing. Because zinc deficiency may be common in the United States, foods rich in zinc, as well as all other essential nutrients, should be promoted in the diet of patients who are malnourished or at risk for malnutrition.

Effects of supplemental pantothenic acid on wound healing: experimental study in rabbit.

Aprahamian M, Dentinger A, Stock-Damge C, Kouassi JC, Grenier JF.

Am J Clin Nutr 1985 Mar;41(3):578-89

The effect of pantothenic acid supplementation and deficiency on wound healing was investigated over a one month postoperative period in rabbits. The supplemented group was injected with pentothenate (20 mg/kg of body weight/24 h) for three weeks and compared to a placebo group (0.5 ml of distilled water). Deficient animals were fed with a pantothenate free diet also for three weeks. These three experimental groups were matched against a control group. The degree of wound healing was determined by the mean of postoperative breaking strength and wound fibroblast population changes. Pantothenic acid urinary excretion measured by gas chromatography served as control of pantothenate consumption. With regard to these three parameters no significant difference has been found between placebo and controls. The average urinary elimination in the pantothenic acid group was significantly higher as far as the pantothenate supplemented group was concerned, while the deficient group showed no significant decrease when compared to controls. Chronic pre- and postoperative pantothenic acid supplementation significantly increased aponeurosis strength after surgery; it improved slightly, but not significantly the strength of the skin. Furthermore, the fibroblast content of the scar became significantly greater during the fibroblast proliferation phase after pantothenic supplementation. These data suggest that pantothenic acid induces an accelerating effect of the normal healing process. The mechanism responsible for this improvement seems to be an increase in cellular multiplication during the first postoperative period. But the exact intimate mechanism of the beneficial effect of pantothenate remains unclear.

Topical estrogen accelerates cutaneous wound healing in aged humans associated with an altered inflammatory response.

Ashcroft GS, Greenwell-Wild T, Horan MA, Wahl SM, Ferguson MW Oral Infection and Immunity Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland 20892, USA. gashcroft@ydir.nidcr.nih.gov

Am J Pathol 1999 Oct;155(4):1137-46

The effects of intrinsic aging on the cutaneous wound healing process are profound, and the resulting acute and chronic wound morbidity imposes a substantial burden on health services. We have investigated the effects of topical estrogen on cutaneous wound healing in healthy elderly men and women, and related these effects to the inflammatory response and local elastase levels, an enzyme known to be up-regulated in impaired wound healing states. Eighteen health status-defined females (mean age, 74.4 years) and eighteen males (mean age, 70.7 years) were randomized in a double-blind study to either active estrogen patch or identical placebo patch attached for 24 hours to the upper inner arm, through which two 4-mm punch biopsies were made. The wounds were excised at either day 7 or day 80 post-wounding. Compared to placebo, estrogen treatment increased the extent of wound healing in both males and females with a decrease in wound size at day 7, increased collagen levels at both days 7 and 80, and increased day 7 fibronectin levels. In addition, estrogen enhanced the strength of day 80 wounds. Estrogen treatment was associated with a decrease in wound elastase levels secondary to reduced neutrophil numbers, and decreased fibronectin degradation. In vitro studies using isolated human neutrophils indicate that one mechanism underlying the altered inflammatory response involves both a direct inhibition of neutrophil chemotaxis by estrogen and an altered expression of neutrophil adhesion molecules. These data demonstrate that delays in wound healing in the elderly can be significantly diminished by topical estrogen in both male and female subjects.

Depletion of plasma vitamin C but not of vitamin E in response to cardiac operations.

Ballmer PE, Reinhart WH, Jordan P, Buhler E, Moser UK, Gey KF. Department of Medicine, Inselspital, University of Berne, Switzerland.

J Thorac Cardiovasc Surg 1994 Aug;108(2):311-20

The whole-body inflammatory response produced by cardiopulmonary bypass is an important cause of perioperative morbidity after cardiac operations. This inflammatory response produces reactive oxygen species and other cytotoxic substances, such as the cytokines. The generation of reactive oxygen species might deplete principal antioxidant micronutrients, that is, vitamins C and E and the carotenoids. Therefore, we have investigated the time course of the plasma concentrations of vitamins C and E and the carotenoids in 18 patients undergoing coronary bypass operations after randomization for previous vitamin E supplementation (300 mg dl-alpha-acetyl-tocopherol 3 times daily for 4 weeks) or placebo. Supplementation with alpha-tocopherol doubled the lipid-standardized plasma vitamin E concentration to 63.7 +/- 14.5 mumol/L when compared with that of the control subjects (31.2 +/- 9.0 mumol/L) before the operation. The plasma concentrations of vitamin C (36.0 +/- 19.0 mumol/L and 44.0 +/- 21.7 mumol/L, respectively) and of the carotenoids were not statistically different between the two groups at baseline. The absolute plasma concentrations of both vitamin E and the carotenoids decreased during and after cardiopulmonary bypass, but after correction for hemodilution the plasma concentrations of vitamin E and the carotenoids showed no decrease. The vitamin E concentrations in the erythrocytes did not change either. In contrast, the plasma concentration of vitamin C decreased in all subjects within 24 hours after the operation by roughly 70%. Correction for hemodilution still revealed a significant decrease in plasma vitamin C that persisted in most patients up to 2 weeks. In conclusion, the vitamin E and the carotenoid plasma concentrations are of no major concern during and after cardiac operations. In contrast, the serious depletion of vitamin C may deteriorate the defense against reactive oxygen species-induced injury during cardiac operations.

Biomechanical and histological aspects of fracture healing, stimulated with osteogenic protein-1.

Blokhuis TJ, den Boer FC, Bramer JA, Jenner JM, Bakker FC, Patka P, Haarman HJ. Department of Surgery/Traumatology, Academic Hospital Vrije Universiteit, Amsterdam, The Netherlands. tj.blokhuis@azvu.nl

Biomaterials 2001 Apr;22(7):725-30

Fracture healing could be stimulated with osteoinductive bone morphogenetic proteins (bmp's), such as osteogenic protein-1 (OP-1), but little is known about its effectiveness in stimulation of fracture healing. In this study, biomechanical and histological aspects of fracture healing after an injection of OP-1 in the fracture gap were investigated. In 40 goats, a closed fracture was created in the left tibia. The fractures were stabilized with an external fixator and the animals were assigned to four different groups: no injection, injection of 1 mg OP-1, injection of 1 mg OP-1 with collagenous carrier material, and injection of carrier material alone. Twenty-one animals were sacrificed after 2 weeks and 19 after 4 weeks. Biomechanical testing was perfomed on both explanted tibiae. Four longitudinal samples of the fracture were sawn, processed for histology, and examined by two observers. Biomechanical evaluation showed a higher stiffness and strength at 2 weeks after injection of OP-1. Histological evaluation showed normal fracture healing patterns in all animals without adverse effects of the given injections. These data show that fracture healing can be accelerated with a single injection of OP-1, eventually resulting in normally healed bone.

Effects of exogenous zinc supplementation on intestinal epithelial repair in vitro.

Cario E, Jung S, Harder D'Heureuse J, Schulte C, Sturm A, Wiedenmann B, Goebell H, Dignass AU. University of Essen, Essen, Germany; Charite Medical School-Campus Virchow, Berlin, Germany.

Eur J Clin Invest 2000 May;30(5):419-28

BACKGROUND: Substitution of zinc modulates antioxidant capabilities within the intestinal mucosa and improves intestinal wound healing in zinc-deficient patients with inflammatory bowel diseases. The aim of this study was to characterize the modulating effects of zinc on intestinal epithelial cell function in vitro.

MATERIALS AND METHODS: The effects of zinc on intestinal epithelial cell morphology were assessed by phase contrast and transmission electron microscopy using the non-transformed small intestinal epithelial cell line IEC-6. Zinc-induced apoptosis was assessed by DNA fragmentation analysis, lactate dehydrogluase (LDH) release and flow cytometry with propidium iodine staining. Furthermore, the effects of zinc on IEC-6 cell proliferation were assessed using a colorimetric thiazolyl blue (MTT) assay and on IEC-6 cell restitution using an in vitro wounding model.

RESULTS: Physiological concentrations of zinc (25 microM) did not significantly alter the morphological appearance of IEC-6 cells. However, a 10-fold higher dose of zinc (250 microM) induced epithelial cell rounding, loss of adherence and apoptotic characteristics. While physiological zinc concentrations (< 100 microM) did not induce apoptosis, supraphysiological zinc concentrations (> 100 microM) caused apoptosis. Physiological concentrations of zinc (6.25-50 microM) had no significant effect on intestinal epithelial cell proliferation. In contrast, physiological concentrations of zinc (12.5-50 microM) significantly enhanced epithelial cell restitution through a transforming growth factor-beta (TGFbeta)-independent mechanism. Simultaneous addition of TGFbeta and zinc resulted in an additive stimulation of IEC-6 cell restitution.

CONCLUSION: Zinc may promote intestinal epithelial wound healing by enhancement of epithelial cell restitution, the initial step of epithelial wound healing. Zinc supplementation may improve epithelial repair; however, excessive amounts of zinc may cause tissue injury and impair epithelial wound healing.

Insulin-like growth factor-1 modulation of intestinal epithelial cell restitution.

Chen K, Nezu R, Wasa M, Sando K, Kamata S, Takagi Y, Okada A. Department of Biochemistry and Biophysics, University of Rochester Medical Center, New York, USA.

JPEN J Parenter Enteral Nutr 1999 Sep-Oct;23(5 Suppl):S89-92

After superficial intestinal injury, the mucosal integrity is reestablished by rapid migration of epithelial cells from the adjacent area in a process called restitution. Our previous study suggested that growth hormone improves intestinal healing in an experimental small bowel ulceration, mediated by insulin-like growth factor-1 (IGF-1). The aim of the present study was to assess the role of IGF-1 in mucosal epithelial restitution using an in vitro epithelial wound model. Wounds were established in confluent monolayers of the intestinal cell line, IEC-6. Migration was quantitated in the presence or absence of IGF-1 as the number of cells migrating across the wound edge. Proliferation was assessed by thymidine incorporation. IGF-1-enhanced epithelial cell migration by 2- to 2.5-fold after 12- and 24-hour treatment, respectively, the first step involved in gastrointestinal wound healing. Cell proliferation was significantly stimulated by IGF-1 as well. In addition, expression of transforming growth factor-beta (TGF-beta) mRNA was significantly enhanced in the wounded monolayers treated with IGF-1. IGF-1 receptor mRNA was found to be detectable throughout the gastrointestinal mucosa and in the intestinal epithelial cells. In conclusion, these findings suggest that IGF-1 plays an important role in reconstitution of intestinal epithelial integrity after mucosal injury.

Influence of Aloe vera on collagen characteristics in healing dermal wounds in rats.

Chithra P, Sajithlal GB, Chandrakasan G. Department of Biochemistry, Central Leather Research Institute, Adyar, Madras, India.

Mol Cell Biochem 1998 Apr;181(1-2):71-6

Wound healing is a fundamental response to tissue injury that results in restoration of tissue integrity. This end is achieved mainly by the synthesis of the connective tissue matrix. Collagen is the major protein of the extracellular matrix, and is the component which ultimately contributes to wound strength. In this work, we report the influence of Aloe vera on the collagen content and its characteristics in a healing wound. It was observed that Aloe vera increased the collagen content of the granulation tissue as well as its degree of crosslinking as seen by increased aldehyde content and decreased acid solubility. The type I/type III collagen ratio of treated groups were lower than that of the untreated controls, indicating enhanced levels of type III collagen. Wounds were treated either by topical application or oral administration of Aloe vera to rats and both treatments were found to result in similar effects.

Improvement of nitrogen retention by arginine and glycine supplementation and its relation to collagen synthesis in traumatized mature and aged rats.

Chyun JH, Griminger P.

J Nutr 1984 Sep;114(9):1697-704

The effect of arginine and glycine supplementation on reducing body protein losses and on enhancing wound healing after trauma was studied in two age groups. Mature (4 month) and aged (24 month) Fischer 344 male rats were fed a diet containing 25% casein and 0.4% methionine with or without supplementation with 2.4% arginine . HCl and 1.0% glycine for 7 days before and after laparotomy. Nitrogen (N) balance studies (N intake - urinary N) were carried out during the last three pretrauma days and seven posttrauma days. The supplemented rats retained significantly more N than the controls and the mature rats significantly more than the aged rats. Polyvinyl alcohol sponges, implanted during surgery and removed from the rats on day 3 or 7 after surgery, were analyzed for hydroxyproline content and for the ratios of type III/type I collagen synthesized. Sponges obtained from the supplemented and the mature rats had more hydroxyproline and higher ratios of type III/type I collagen than those from the control and the aged rats. The beneficial effect of arginine and glycine supplementation on improving N retention in traumatized rats appears to be due, at least in part, to increased collagen synthesis in wounds.

Enteral nutrition during multimodality therapy in upper gastrointestinal cancer patients.

Daly JM, Weintraub FN, Shou J, Rosato EF, Lucia M. Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia, USA.

Ann Surg 1995 Apr;221(4):327-38

OBJECTIVE: The objective of this study was to evaluate long-term enteral nutrition support in postoperative cancer patients.

BACKGROUND: Multimodality therapy for surgical patients with upper gastrointestinal malignancies may improve survival, but often results in substantial malnutrition, immunosuppression, and morbidity. The benefits of combined inpatient and outpatient enteral feeding with standard diets or diets supplemented with arginine, RNA + omega-3 fatty acids are unclear.

METHODS: Sixty adult patients with esophageal (22), gastric (16), and pancreatic (22) lesions were stratified by disease site and percent usual weight and randomized to receive supplemental or standard diet via jejunostomy beginning on the first postoperative day (goal = 25 kcal/kg/day) until hospital discharge. Patients also were randomized to receive (n = 37) or not receive (n = 23) enteral jejunostomy feedings (1000 kcal/day overnight) for the 12- to 16-week recovery and radiation/chemotherapy periods. Plasma and peripheral white blood cells were obtained for fatty acid levels and PGE2 production measurements.

RESULTS: Mean plasma and cellular omega 3/omega 6 fatty acid levels (percent composition) increased significantly (p < 0.05) in the arginine + omega-3 fatty acid group by postoperative day 7 (0.30 vs. 0.13) and (0.29 vs. 0.14) and continued to increase over time. Mean PGE2 production decreased significantly (p < 0.05) from 2760 to 1600 ng/10(6) cells/mL at day 7 in the arginine + omega-3 fatty acid group, whereas no significant change over time was noted in the standard group. Infectious/wound complications occurred in 10% of the supplemented group compared with 43% of the standard group (p < 0.05); mean length of hospital stay was 16 vs. 22 (p < 0.05) days, respectively. Of the patients who received postoperative chemoradiation therapy, only 1 (6%) of the 18 patients randomized to receive tube feeding did not continue, whereas 8 (61%) of the 13 patients not randomized to tube feedings required crossover to jejunostomy nutritional support.

CONCLUSIONS: Supplemental enteral feeding significantly increased plasma and peripheral white blood cell omega 3/omega 6 ratios and significantly decreased PGE2 production and postoperative infectious/wound complications compared with standard enteral feeding. For outpatients receiving adjuvant therapy, those initially randomized to oral feedings alone required rehospitalization more frequently, and 61% crossed over to supplemental enteral feedings.

The use of adjuvant hyperbaric oxygen in treatment of the diabetic foot.

Davis JC.

Clin Podiatr Med Surg. 1987 Apr;4(2):429-37.

Hypoxia in the relatively ischemic diabetic foot impairs leukocyte bacterial killing and fibroblast-collagen support for capillary angiogenesis. Infection in even the relatively young, "warm-foot" diabetic with microangiopathy, neuropathy, and infection leads to hypoxia due to local high oxygen consumption. The 1100 to 1300 mm Hg arterial PO2 achievable with hyperbaric oxygen results in elevation of wound PO2. Periodic correction of wound hypoxia improves leukocyte bacterial killing and support for capillary angiogenesis. Hyperbaric oxygen is usually futile in the elderly diabetic with significant and generalized large-vessel occlusion.

Reversal of the detrimental effects of chronic protein malnutrition on long bone fracture healing.

Day SM, DeHeer DH. Grand Rapids Orthopaedic Surgery Residency Program, Grand Rapids, Michigan, USA.

J Orthop Trauma 2001 Jan;15(1):47-53

OBJECTIVE: To determine whether dietary intervention in the immediate postfracture period will reverse the detrimental influence of protein deprivation on fracture healing in the rat. DESIGN: Adult Sprague-Dawley rats were maintained on a diet containing either a normal or reduced protein concentration. After five weeks, both femora of each rat were pinned with an intramedullary 0.625-millimeter K-wire. A closed fracture of the right femur was created one week later, by use of a handheld device. Groups of rats were killed and the femora harvested at 14 days for histologic study and at twenty-eight and fifty-six days for mechanical testing.

INTERVENTION: Control rats (Group I) were maintained on a 20 percent protein diet. Malnourished (Group II) animals were maintained on a 6 percent protein diet during the six-week prefracture period and throughout the fifty-six-day postfracture period. Malnutrition was confirmed by measurement of serum concentrations of transferrin, immunoglobulin, and albumin. Renourished (Group III) animals were started on the 6 percent protein diet but were fed a 20 percent protein diet in the fifty-six-day postfracture period.

RESULTS: When compared with control, well-nourished rats, malnourished animals had callus composed primarily of fibrous-type tissue and had decreased periosteal and external callus as well as callus strength. The callus from renourished animals histologically resembled that from well-nourished animals with large amounts of periosteal and external callus. Based on mechanical testing results, callus from malnourished animals showed reduced strength and stiffness as compared with control renourished animals. In renourished animals, the cross-sectional area of the fracture callus, as well as callus stiffness and strength, were greater than those in malnourished and well-nourished animals.

CONCLUSION: Protein deprivation has a profound detrimental effect on fracture healing. The identification of a protein-reduced state and its reversal could result in improved fracture healing and presumably a better clinical outcome in malnourished patients.

Pharmacological nutrition after burn injury.

De-Souza DA, Greene LJ. Centro de Quimica de Proteinas, Faculdade de Medicina de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto, 14049-900, S.P., Brazil.

J Nutr 1998 May;128(5):797-803

Burn patients develop pathophysiological alterations, which include extensive nitrogen loss, malnutrition, markedly increased metabolic rate and immunologic deficiency. This predisposes burn patients to frequent infections, poor wound healing, increased length of hospitalization and increased mortality. The nutritional support requires high protein and high energy diets preferably administered enterally soon after injury. The effects of increased dietary components such as glutamine, arginine and (n-3) fatty acids and related compounds have been evaluated in burn victims. These components, when supplied in quantities two to seven times of those in normal diets of healthy persons, appear to have beneficial pharmacological effects on the pathophysiological alterations associated with burns. However, the efficacy of immune-enhancing diets remains to be convincingly shown.

Superoxide dismutase (SOD) for mustard gas burns.

Eldad A, Ben Meir P, Breiterman S, Chaouat M, Shafran A, Ben-Bassat H. The Burn Unit, The Department of Plastic Surgery, School of Pharmacology, The Hebrew University, Jerusalem, Israel.

Burns 1998 Mar;24(2):114-9

Mustard gas (MS) has been used in chemical warfare since World War I. The blistering skin lesions are slow to heal. Secondary inflammation might occur, as well as damage to organs distant from the original wound. Presently there is no specific antidote for burns and poisoning by MS. This study examined treatment modalities with free oxygen radical scavengers, copper-zinc, and manganese superoxide dismutase (SOD), for MS skin burns in an experimental guinea pig model. Each of the SOD compounds reduced dramatically burn lesion area when administered intraperitoneally/intralesionally (i.p./i.l.) before wound infliction. The protective action of the SODs was also evident in the significantly higher histopathological score of biopsies obtained on day 7 from local tissue, caused with the lower dose of MS. When the SOD compounds were administered i.p. 1 hour after burn infliction, and repeated daily for 7 days, no protective effect could be detected under the present experimental conditions.

Wound healing after photorefractive keratectomy.

Fagerholm P. St. Eriks Eye Hospital, Karolinska Institutet, Stockholm, Sweden.

J Cataract Refract Surg. 2000 Mar;26(3):432-47.

For more than 15 years, the excimer laser has been used as a surgical instrument on the cornea. Photorefractive keratectomy (PRK) followed radial keratotomy as researchers sought a more precise technique. In PRK, precision turned out to depend on surgical technique as well as the wound-healing process, with the 2 factors interdependent. The PRK technique has evolved toward a large diameter, flat ablation curvatures, and an even surface. The role of such factors as cytokines and interleukins has become more clear in the past 10 years. However, understanding the wound-healing process becomes more complicated with increasing know edge. Learning the contributing factors and performing trials with new drugs and antibodies to modulate wound healing have shown positive results on the experimental level. Patient selection based on the concentration of epidermal growth factor in tears may be another way to increase PRK s precision. The PRK technique has taught much about wound healing. For the technique to be competitive, increased precision, particularly in eyes with high myopia, is needed. Two other factors are imperative: controlling postoperative pain and decreasing visual rehabilitation time.

Burn injuries benefit from massage therapy.

Field T; Peck M; Krugman S; Tuchel T; Schanberg S; Kuhn C; Burman I Touch Research Institute, University of Miami School of Medicine, Florida 33101, USA.

J Burn Care Rehabil (UNITED STATES) May-Jun 1998 , 19 (3) p241-4

Twenty-eight adult patients with burns were randomly assigned before debridement to either a massage therapy group or a standard treatment control group. State anxiety and cortisol levels decreased, and behavior ratings of state, activity, vocalizations, and anxiety improved after the massage therapy sessions on the first and last days of treatment. Longer- term effects were also significantly better for the massage therapy group including decreases in depression and anger, and decreased pain on the McGill Pain Questionnaire, Present Pain Intensity scale, and Visual Analogue Scale. Although the underlying mechanisms are not known, these data suggest that debridement sessions were less painful after the massage therapy sessions due to a reduction in anxiety, and that the clinical course was probably enhanced as the result of a reduction in pain, anger, and depression.

Interleukin-6 treatment augments cutaneous wound healing in immunosuppressed mice.

Gallucci RM, Sugawara T, Yucesoy B, Berryann K, Simeonova PP, Matheson JM, Luster MI. Toxicology and Molecular Biology Branch, Health Effects Laboratory Division, NIOSH/CDCP, 1095 Willowdale Road, Morgantown, WV 26505-2888, USA.

J Interferon Cytokine Res 2001 Aug;21(8):603-9

It has been postulated that the inflammatory response that occurs aftercutaneous wounding is a prerequisite for healing and that inflammatorycytokines, such as Interleukin-6 (IL-6) are involved in this process. We showed previously that IL-6-deficient mice display delayed wound healing, which could be reversed by administration of a murine IL-6 expression plasmid or recombinant murine IL-6 (rMuIL-6). In the present study, we observed that delayed cutaneous wound healing, which occurs as a result of glucocorticoid-induced immunosuppression, can also be reversed by rMuIL-6, as evidenced by epithelialization, granulation tissue formation, and wound closure. In vehicle control mice, rMuIL-6 did not augment healing but rather delayed the process. Immunochemical studies indicated that the expression of matrix metalloproteinase-10 (MMP-10) was increased in dexamethasone-treated mice and that rMuIL-6 treatment reduced its expression, indicating that IL-6 may influence dermal matrix formation and, specifically, collagen synthesis. These results demonstrate that IL-6 can restore abnormal wound repair that occurs in immunodeficiency and suggest its use as a potential therapy.

Effects of epidermal growth factor in artificial tear on vitamin C levels of corneal wounded eye tissues.

Gonul B, Kaplan B, Bilgihan K, Budak MT. Department of Physiology, Gazi University Faculty of Medicine, Ankara, Turkey. hbcgonul@turk.net

Eye 2001 Apr;15(Pt 2):213-6

PURPOSE: To investigate the effect of artificial tear (AT) solution and epidermal growth factor (EGF) treatment on the cornea and aqueous humour ascorbic acid (AA) levels of full-thickness corneal wounded eyes.

METHODS: The effect of EGF on the AA levels of aqueous humour and corneal wound tissue was determined in full-thickness corneal wounded rabbit eyes on the seventh post-operative day. There were three groups: untreated controls, AT-treated controls and an EGF treated experimental group (n = 6 in each group). Corneal wounded eyes were topically treated with 5 microl AT or 5 microl EGF in AT (1 mg/l EGF in AT preparation which contained 3.0% carbopol 940) twice daily for 6 days after operation. The wound strengths were also measured on the seventh post-operative day as a measure of wound healing. Statistical analysis was carried out using the Mann-Whitney U-test by Statview program.

RESULTS: The wound strengths of corneas, and AA levels of wound tissues and aqueous humour, increased significantly following AT and EGF treatment (p < 0.05).

CONCLUSION: In the corneal wounded eye, aqueous humour serves as a source of vitamin C and there may be a relation between EGF treatment in AT and AA levels of corneal wounded eye tissues.

Topical insulin in wound healing: a randomised, double-blind, placebo-controlled trial.

Greenway SE, Filler LE, Greenway FL. Department of Surgery, Harbor-UCLA Medical Center, Torrance, USA.

J Wound Care 1999 Nov;8(10):526-8

Two studies were carried out to assess the relative roles of insulin and zinc in the acceleration of wound healing. In the first study, six diabetic and five non-diabetic human volunteers had two uniform cuts created, one on each forearm. One forearm wound was treated with topical regular insulin (Iletin-II) and the other with normal saline four times a day until healed. Treatment was double-blind and forearms were assigned randomly. The wounds treated with insulin healed 2.4 0.8 days faster than the wounds treated with saline (P <0.001 by paired t-test). Zinc is used to crystallise insulin. When wounds are treated with insulin, they are therefore also being treated with zinc. If insulin accelerates wound healing, it is not clear if the increase in the rate of healing would be due to insulin (a known growth factor), the zinc it contains, or a combination of the two. The second study used a randomised, double-blind, placebo-controlled design to compare the efficacy of insulin with that of a solution containing the same amount of zinc in accelerating the healing of standardised wounds in rats and humans. Although these pilot investigations did not have the power to define the relative roles of insulin and zinc with accuracy, the results suggest that zinc does play a role in the wound healing process. It is concluded that topical insulin accelerates wound healing in humans. More importantly, however, this study describes a method of creating uniform wounds in humans acceptable to an institutional review board, thus solving one of the major impediments to the scientific evaluation of human wound healing.

Supplemental dietary arginine accelerates intestinal mucosal regeneration and enhances bacterial clearance following radiation enteritis in rats.

Gurbuz AT, Kunzelman J, Ratzer EE. Department of Surgery, Saint Joseph Hospital Medical Center, Denver, Colorado, USA. tayfun@netten.net

J Surg Res 1998 Feb 1;74(2):149-54 BACKGROUND: Arginine is a dibasic amino acid with significant metabolic and immunologic, effects especially in trauma and stress situations. Arginine supplementation has been shown to promote wound healing and improve immune system. We designed a study to evaluate the effects of supplemental dietary arginine on intestinal mucosal recovery and bacterial translocation and bacterial clearance after induction of radiation injury in rats.

METHODS: Twenty-one male Sprague-Dawley rats were subjected to a single dose of 1100 rads of abdominal X radiation. Rats were divided into three groups; the first group received diet enriched with 2% arginine, the second group with 4% arginine, and the third group with isonitrogenous 4% glycine. Rats were sacrificed 7 days after the radiation. Blood was drawn for arginine levels and mesenteric lymph nodes were harvested for quantitative aerobic and anaerobic cultures. Segments of ileum and jejunum were evaluated for villous height, number of villi per centimeter of intestine, and the number of mucous cells per villous.

RESULTS AND CONCLUSIONS: Arginine is absorbed reliably from the gut following oral administration. Dietary 4% arginine supplementation enhanced bacterial clearance from mesenteric lymph nodes compared to 2% arginine and 4% glycine supplemented diet following radiation enteritis in rats. Four percent arginine resulted in clear improvement in intestinal mucosal recovery when compared to 2% arginine and 4% glycine after abdominal irradiation in rats.

Omega-3 fatty acids enhance ligament fibroblast collagen formation in association with changes in Interleukin-6 production.

Hankenson KD, Watkins BA, Schoenlein IA, Allen KG, Turek JJ. Department of Basic Medical Sciences, Lipid Chemistry Laboratory, Purdue University, West Lafayette, Indiana 47907, USA.

Proc Soc Exp Biol Med 2000 Jan;223(1):88-95

Altering dietary ratios of n-3 and n-6 polyunsaturated fatty acids (PUFA) represents an effective nonpharmaceutical means to improve systemic inflammatory conditions. An effect of PUFA on cartilage and bone formation has been demonstrated, and the purpose of this study was to determine the potential of PUFA modulation to improve ligament healing. The effects of n-3 and n-6 PUFA on the in vitro healing response of medial collateral ligament (MCL) fibroblasts were investigated by studying the cellular coverage of an in vitro wound and the production of collagen, PGE2, IL-1, IL-6, and TNF. Cells were exposed to a bovine serum albumin (BSA) control or either eicosapentaenoic acid (EPA, 20:5n-3) or arachidonic acid (AA, 20:4n-6) in the form of soaps loaded onto BSA for 4 days and wounded on Day 5. AA and EPA improved the healing of an in vitro wound over 72 hr. EPA increased collagen synthesis and the overall percentage of collagen produced, but AA reduced collagen production and total protein. PGE2 production was increased in the AA-treated group and decreased in the EPA-treated group, but was not affected by wounding. IL-1 was not produced at the time point evaluated, but TNF and IL-6 were both produced, and their levels varied relative to the PUFA or wounding treatment. There was a significant linear correlation (r2 = 0.57, P = 0.0045) between IL-6 level and collagen production. These results demonstrate that n-3 PUFA (represented by EPA in this study) positively affect the healing characteristics of MCL cells and therefore may represent a possible noninvasive treatment to improve ligament healing. Additionally, these results show that MCL fibroblasts produce PGE2, IL-6, and TNF and that IL-6 production is related to MCL collagen synthesis.

Ascorbic acid in the prevention and treatment of cancer.

Head KA. Alternative Medicine Review. P.O. Box 25, Dover, ID 83825, USA. kathi@thorne.com

Altern Med Rev 1998 Jun;3(3):174-86

Proposed mechanisms of action for ascorbic acid (ascorbate, vitamin C) in the prevention and treatment of cancer include enhancement of the immune system, stimulation of collagen formation necessary for "walling off" tumors, inhibition of hyaluronidase which keeps the ground substance around the tumor intact and prevents metastasis, prevention of oncogenic viruses, correction of an ascorbate deficiency often seen in cancer patients, expedition of wound healing after cancer surgery, enhancement of the effect of certain chemotherapy drugs, reduction of the toxicity of other chemotherapeutic agents such as Adriamycin, prevention of free radical damage, and neutralization of carcinogenic substances. Scottish as well as Japanese studies have pointed to the potential benefit of high dose vitamin C for the treatment of "terminal" cancer. Mayo Clinic studies, however, have contradicted the Scottish and Japanese findings, resulting in accusations of methodological flaws from both sides. Numerous epidemiological studies have pointed to the importance of dietary and supplemental ascorbate in the prevention of various types of cancer including bladder, breast, cervical, colorectal, esophageal, lung, pancreatic, prostate, salivary gland, stomach, leukemia, and non-Hodgkin's lymphoma.

Effect of the combination of Aloe vera, nitroglycerin, and L-NAME on wound healing in the rat excisional model.

Heggers JP, Elzaim H, Garfield R, Goodheart R, Listengarten D, Zhao J, Phillips LG. University of Texas Medical Branch, Galveston, USA.

J Altern Complement Med 1997 Summer;3(2):149-53

PURPOSE: Many systemic and topical therapeutic agents such as growth hormone, platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), epidermal growth factor (EGF), and insulin-like growth factor (IGF) have been used as vulnerary agents. However, the role of nitric oxide (NO) as a wound-healing stimulant has been received with mixed reviews. NO is a potent vasodilator that is thought to be an endothelium-dependent relaxing factor, and a regulator of blood pressure and regional blood flow. It affects vascular smooth muscle proliferation and inhibits platelet aggregation and leukocyte adhesion. Therefore we compared the effects of several topical substances that have similar or reverse properties.

METHODS: Using the excisional rat wound model, we evaluated the topical effects of Dermaide Aloe (D-Aloe, Dermaide Research Corp, Palos Heights, IL), nitroglycerin, Aquaphor (Beuersdorf, Inc., Norwalk, CT) alone, with D-Aloe with nitroglycerin, 2%, and L-NAME (NO inhibitor) with Aquaphor, and L-NAME with Aquaphor and D-Aloe for a 21-day period. All wounds were measured by planimetry at 1, 7, 10, 13, 16, 18, and 21 days.

RESULTS: At day 1, all wounds had an average wound size of 2.27 cm2 (SD 0.372) with no significant difference in wound size among the groups. Topically applied D-Aloe appeared to promote wound healing faster than the remaining other topicals (p <.05, Student-Newman-Keuls and Dunn's Method) over the study period. However, topicals combined with D-Aloe, the vehicle Aquaphor, and L-NAME improved the wound healing process when compared with nitroglycerin alone (p < .05).

CONCLUSIONS: D-Aloe appears to have a wound-healing advancement factor that can reverse the effects of petrolatum- and nitroglycerin-based products as observed in the remaining groups when compared with nitroglycerin alone. It appears that D-Aloe's effect of preventing dermal ischemia by reversing the effects of thromboxane synthetase (TxA2) may act synergistically with NO or could be an oxygen radical scavenger.

Topical hyperbaric therapy for problem skin wounds

Heng M.C.Y. Division of Dermatology, Veterans Administration Medical Ctr., UCLA School of Medicine, 16111 Plummer Street,Sepulveda, CA 91343 United States

Journal of Dermatologic Surgery and Oncology (United States) 1993, 19/8 (784-793) BACKGROUND. Hyperbaric oxygen remains the sole treatment capable of inducing growth of new blood vessels. However, systemic hyperbaric oxygen therapy risks central nervous system and pulmonary toxicity.

OBJECTIVE. To describe topical hyperbaric oxygen therapy for the treatment of recelcitrant open wounds.

METHODS. Topical and systemic hyperbaric oxygen treatments are described and contrasted from one another. Applications of topical hyperbaric oxygen therapy are described.

CONCLUSION. Topical hyperbaric oxygen therapy is useful only for open wounds. The advantages of topical hyperbaric oxygen therapy include low cost, the lack of systemic oxygen toxicity, and effectiveness, allowing this treatment to be prescribed for many patients early in the course of their disease rather than as a last resort.

Up-regulation of elastase in acute wounds of healthy aged humans and chronic venous leg ulcers are associated with matrix degradation.

Herrick S, Ashcroft G, Ireland G, Horan M, McCollum C, Ferguson M School of Biological Sciences, University of Manchester, United Kingdom.

Lab Invest 1997 Sep;77(3):281-8

Chronic wound healing states are often associated with aging, and despite the increased number of aged patients with nonhealing wounds, controversy still exists concerning the effects of age on wound repair. Our previous work showed that in both venous ulcers in humans and acute wounds in aged animals, fibronectin, an early component in granulation tissue, is deficient compared to normal skin and acute wounds in healthy young animals, respectively. In the present study, we have determined the protease responsible for fibronectin degradation by analyzing tissue taken from the margins of chronic venous ulcers and standardized acute cutaneous wounds collected from a large cohort of "Health status"-defined aged human subjects (screened as per the SENIEUR protocol). When tissue samples were subjected to fibronectin zymography, the main protease involved in the breakdown of fibronectin in both venous ulcers and acute wounds of elderly subjects was found to be a serine protease with a molecular weight of approximately 30 kd. This protease was identified as neutrophil elastase by immunoblotting. In tissue biopsies, elastase was localized to granulocytes by immunocytochemical techniques and shown to be present in greater quantities in venous ulcers and Day-7 and -14 healing acute wounds of healthy aged subjects relative to those of young subjects. The highest quantities were found in acute wounds of elderly women. Our results suggest that the process of aging in healthy human subjects is associated with an up-regulation of elastase during acute wound healing and that an abnormality in down-regulation of this protease could be partially responsible for the transition to chronic wound healing states in the aged.

Drotrecogin alfa (activated): the first FDA-approved treatment for severe sepsis.

Hosac, A.M.

BUMC Proc. 2002; 15: 224-7.

No abstract available.

Nutritional and metabolic effects and significance of mild orotic aciduria during dietary supplementation with arginine or its organic salts after trauma injury in rats.

Jeevanandam M, Begay CK, Holaday NJ, Petersen SR. Trauma Center, St. Joseph's Hospital and Medical Center, Phoenix, AZ 85013, USA.

Metabolism 1997 Jul;46(7):785-92

The effects of acute food deprivation and subsequent refeeding with isonitrogenous oral liquid diets supplemented with arginine (ARG), ARG alpha-ketoglutarate (AKG), or ARG alpha-ketoisocaproate (AKIC) were examined in a Sprague-Dawley rat trauma model (bilateral femur fracture). Both control and trauma rats were starved for 2 days and then pair-fed for 4 days with one of four liquid isonitrogenous diets: diet 1 was a basal casein-based diet, and diets 2, 3, and 4 were the basal diet in which 10% of the nitrogen was replaced by ARG, AKG, or AKIC nitrogen. Two days of starvation resulted in a 13% loss of body weight and also a 27% decrease in the excretion of orotic acid (OA) in control and trauma rats. Although the ARG content of diets 2, 3, and 4 was the same, ARG- and AKIC-supplemented rats excreted significantly (P < .05) more OA than AKG-fed rats. The low level of OA excretion in AKG-fed rats indicates greater use of ARG for metabolic purposes, including efficient urea cycle operation. The metabolic adaptation and nutritional efficacy, i.e., Increased nitrogen retention, larger weight gain, and altered amino acid (AA) metabolism, of AKIC rats seem to be better than in ARG- or AKG-fed rats.

Keratinocyte growth factor-2 accelerates wound healing in incisional wounds.

Jimenez PA, Rampy MA. Human Genome Sciences, Inc., Rockville, Maryland, 20850, USA. jimenez@hgsi.com

J Surg Res 1999 Feb;81(2):238-42

BACKGROUND: Keratinocyte growth factor-2 (KGF-2) also described as fibroblast growth factor-10 (FGF-10) is a newly identified member of the fibroblast growth factor family. KGF-2 is 96% identical to the recently identified rat FGF-10 and specifically stimulates growth of normal human epidermal keratinocytes. The present study was undertaken to examine the effects of topically applied KGF-2 in an incisional wound healing model. KGF-2 treatment resulted in an improvement in incisional wound healing as characterized by an increase in breaking strength, collagen content, and epidermal thickness.

METHODS: KGF-2 was topically applied to linear incisions made in the dorsal skin of Sprague-Dawley rats. Biomechanical testing was done using an Instron tensiometer for breaking and tensile strength determinations. Wound collagen content was determined using the Sircol collagen assay. Epidermal thickness measurements were conducted using Masson's trichrome-stained sections of the wound.

RESULTS: A single topical application of KGF-2 at the time of wounding resulted in an increase in wound breaking and tensile strength at Day 5 after wounding. Breaking strength of KGF-2-treated wounds was significantly higher compared with the buffer control (1 microgram, 222.1 +/- 13.5 g, P = 0.0007; 4 microgram, 248.7 +/- 15.4 g, P = 0.0001; 10 microgram, 247.2 +/- 21.9 g, P = 0.001; buffer, 141.0 +/- 9.7 g). Epidermal thickness and wound collagen content were significantly increased following treatment with KGF-2.

CONCLUSIONS: Based on our findings, KGF-2 is a potent stimulator of wound healing as demonstrated by increased mechanical strength accompanied by an increase in wound collagen content. KGF-2 could be an important cellular mediator responsible for the initiation and acceleration of wound healing and may enhance the healing of surgical wounds. Copyright 1999 Academic Press.

Effect of Ca-panthotenate on human granulocyte oxidative metabolism.

Kapp A, Zeck-Kapp G. Department of Dermatology, University of Freiburg.

Allerg Immunol (Leipz) 1991;37(3-4):145-50

Activated granulocytes play an important role in propagation of the inflammatory response by production of reactive oxygen species and release of their granule content. Hyperactivation of these cells is suggested to result in deterioration of wound healing and, probably, increase of cicatrization. Pantothenic acid and its stable salt form, Ca-Panthotenate, were shown to significantly improve surgical wound healing. Therefore, in the present study the modulating effect of Ca-pantothenic acid to subsequent stimulation with a variety of stimuli was investigated on isolated human PMN using functional assay systems: Lucigenin-dependent chemiluminescence (CL), release of myeloperoxidase (MPO). Ca-Panthotenate significantly inhibited the CL response of PMN upon stimulation with the chemotactic petide f-met-leu-phe, the tumor promotor PMA, and the granulocyte activating cytokines GM-CSF and TNF alpha at a concentration range of 5 to 50 mM, but not upon stimulation with opsonized zymosan. Moreover, Ca-Panthotenate significantly inhibited the release of myeloperoxidase from PMN upon stimulation with f-met-leu-phe at a concentration of 5 mM. In contrast, Ca-Panthotenate did not directly activate PMN in the assay systems tested. These in vitro results support the concept of an anti-inflammatory action of Ca-Panthotenate in vivo.

Proinflammatory cytokines differentially regulate hyaluronan synthase isoforms in fetal and adult fibroblasts.

Kennedy CI, Diegelmann RF, Haynes JH, Yager DR Department of Surgery, Medical College of Virginia Hospitals, Virginia Commonwealth University, Richmond, USA.

J Pediatr Surg 2000 Jun;35(6):874-9

BACKGROUND/PURPOSE: Fetal wound healing is a relatively scarless process that occurs in an hyaluronan-rich environment. Understanding the regulation of hyaluronan expression may provide insight into the process of fetal repair. Therefore, the purpose of this study was to compare the regulation of hyaluronan and hyaluronan synthase transcripts by the proinflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) in human adult and fetal fibroblasts.

METHODS: Hyaluronan deposited in the medium of untreated fibroblasts or fibroblasts treated with either IL-1beta or TNF-alpha was determined by an assay utilizing iodine I 125-hyaluronan binding protein. HAS transcript levels were compared in using a ribonuclease protection assay.

RESULTS: IL-1beta induced an increase in hyaluronan accumulation by both fetal and adult fibroblasts. In contrast, TNF-alpha induced higher levels of hyaluronan only in fetal fibroblasts. HAS-2 and HAS-3 transcript levels were constitutively expressed by both fetal and adult fibroblasts. Proinflammatory cytokines induced a differential increase in HAS-1 and HAS-3 transcript levels.

CONCLUSIONS: Differential regulation was observed in hyaluronan accumulation and for HAS transcript levels in fetal and adult dermal fibroblasts. The muted response of fetal fibroblasts to cytokines may be relevant to the minimal inflammation associated with fetal repair.

Arginine stimulates wound healing and immune function in elderly human beings.

Kirk SJ, Hurson M, Regan MC, Holt DR, Wasserkrug HL, Barbul A. Department of Surgery, Sinai Hospital of Baltimore, MD 21215.

Surgery 1993 Aug;114(2):155-9; discussion 160

BACKGROUND. Experimentally, arginine enhances immune function and promotes wound healing. In this randomized double-blind study we investigated the effect of oral arginine supplementation on wound healing and T-cell function in elderly human beings (more than 65 years of age).

METHODS. Thirty elderly, healthy, human volunteers (15 men and 15 women) received daily supplements of 30 gm arginine aspartate (17 gm free arginine). Fifteen volunteers (nine men and six women) received a placebo syrup. Fibroplastic wound responses were assessed by inserting a polytetrafluoroethylene catheter subcutaneously into the right deltoid region. Epithelialization was examined by creating a 2 x 2 cm split thickness wound on the lateral aspect of the upper thigh. Mitogenic response of peripheral blood lymphocytes to concanavalin A, phytohemagglutinin, pokeweed mitogen, and allogeneic stimuli was assayed at the beginning and end of supplementation. Polytetrafluoroethylene catheters were analyzed for alpha-amino nitrogen (assessment of total protein accumulation), hydroxyproline (index of reparative collagen synthesis), and DNA accumulation (index of cellular infiltration).

RESULTS. Arginine supplementation for 2 weeks significantly enhanced wound catheter hydroxyproline accumulation (26.49 +/- 2.39 nmol/cm vs 17.41 +/- 2.04 nmol/cm) and total protein content (43.47 +/- 3.85 micrograms/cm vs 21.95 +/- 2.5 micrograms/cm). Arginine did not influence the DNA content of the catheters or the rate of epithelialization of the skin defect. Peripheral blood lymphocyte responses to mitogenic and allogenic stimulation were greater in the arginine supplemented group. Serum insulin-like growth factor-1 levels were significantly elevated in the arginine group.

CONCLUSIONS. The data suggest that arginine supplementation may improve wound healing and immune responses in the elderly.

[The modern approach to wound treatment]. [Article in Serbo-Croatian (Roman)]

Komarcevic A. Institut za zdravstvenu zastitu dece i omladine Klinika za decju hirurgiju, Medicinski fakultet, Novi Sad. komarac@Eunet.yu

Med Pregl 2000 Jul-Aug;53(7-8):363-8

INTRODUCTION: Wound healing is a complex process involving interactions among a variety of different cell types. The normal wound repair process consists of three phases--inflammation, proliferation, and remodeling that occur in a predictable series of cellular and biochemical events. Wounds are classified according to various criteria: etiology, lasting, morphological characteristics, communications with solid or hollow organs, the degree of contamination. In the last few years many authors use the Color Code Concept, which classifies wounds as red, yellow and black wounds. This paper presents conventional methods of local wound treatment (mechanical cleansing, disinfection with antiseptic solutions, wound debridement--surgical, biological and autolytic; wound closure, topical antibiotic treatment, dressing), as well as general measures (sedation, antitetanous and antibiotic protection, preoperative evaluation and correction of malnutrition, vasoconstriction, hyperglycemia and steroid use, appropriate surgical technique, and postoperative prevention of vasoconstriction through pain relief, warming and adequate volume resuscitation). THE ROLE OF PHYSIOLOGICAL FACTORS AND ANTIMICROBIAL AGENTS IN WOUND HEALING: Growth factors play a role in cell division, migration, differentiation, protein expression, enzyme production and have a potential ability to heal wounds by stimulating angiogenesis and cellular proliferation, affecting the production and the degradation of the extracellular matrix, and by being chemotactic for inflammatory cells and fibroblasts. There are seven major families of growth factors: epidermal growth factor (EGF), transforming growth factor-beta (TGF-beta), insulin-like growth factor (IGF), platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), interleukins (ILs), and colony-stimulating factor (CSF). Acute wounds contain many growth factors that play a crucial role in the initial phases of wound healing. The events of early wound healing reflect a finely balanced environment leading to uncomplicated and rapid wound healing. Chronic wounds, for many reasons, have lost this fine balance. Multiple studies have evaluated the effect that exogenously applied growth factors have on the healing of chronic wounds. In the study conducted by Knighton and colleagues, topical application of mixture of various growth factors (PDGF, TGF-beta, PDAF, PF4, PDEGF) demonstrated increased wound healing over controls. Brown and associates demonstrated a decrease in skin graft donor site healing time of 1 day using topically applied EGF. Herndon and ass. used systemic growth hormone in burned children and reduction in healing time made a significant clinical difference by allowing earlier wound coverage and decreasing the duration of hospitalization. The TGF family of growth factors is believed to be primarily responsible for excessive scar formation, especially the beta 1 and beta 2 isoforms. TGF-beta 3 isoform has recently been described and may have an inhibitory function on scar formation by being a natural antagonist to the TGF-beta 1 and TGF-beta 2 isoforms. Cytokines, especially interferon-alpha (INF-alpha), INF-alpha, and INF-alpha 2b, may also reduce scar formation. These cytokines decrease the proliferation rate of fibroblasts and reduce the rate of collagen and fibronectin synthesis by reducing the production of mRNA. Expression of nitric oxide synthase (NOS) and heat shock proteins (HSP) have an important role in wound healing, as well as trace elements (zinc, copper, manganese). Applications of some drugs (antioxidants--asiaticoside, vitamin E and ascorbic acid; calcium D-pantothenate, exogenous fibronectin; antileprosy drugs--oil of hydnocarpus; alcoholic extract of yeast) accelerate wound healing. Thymic peptide thymosin beta 4 (T beta 4R) topically applicated, increases collagen deposition and angiogenesis and stimulates keratinocyte migration. Thymosin alpha 1 (T alpha 1R), peptide isolated from the thymus, is a potent chemoattractant which accelerates angiogenesis and wound healing. On the contrary, steroid drugs, hemorrhage and denervation of wounds have negative effect on the healing process.

Fetal wound repair results in scar formation in Interleukin-10-deficient mice in a syngeneic murine model of scarless fetal wound repair.

Liechty KW, Kim HB, Adzick NS, Crombleholme TM. Children's Institute for Surgical Science at The Children's Hospital of Philadelphia, The University of Pennsylvania School of Medicine, 19104, USA.

J Pediatr Surg 2000 Jun;35(6):866-72; discussion 872-3

BACKGROUND: Fetal dermal wound healing is characterized by minimal inflammation, restoration of normal dermal architecture, and scarless repair. The authors have shown that proinflammatory cytokines Interleukin-6 (IL-6) and Interleukin-8 (IL-8) are diminished during fetal wound repair. Interleukin-10 (IL-10) is an antiinflammatory cytokine that decreases production of IL-6 and IL-8. The authors hypothesized that diminished IL-6 and IL-8 and minimal inflammation may be caused by IL-10.

METHODS: To test this hypothesis, the authors developed a new syngeneic murine model of fetal wound repair in which 15-day-gestation skin from either normal C57BL/6 or transgenic C57BL/6 IL-10 knockout mice was grafted to the back of the same strain adult mice. The grafts were incisionally wounded after 5 days, harvested at 1 week, and analyzed for inflammatory response and scar formation.

RESULTS: Wounds in normal fetal skin grafts showed minimal inflammation and normal dermal reticular collagen pattern at the site of the wound, consistent with scarless repair. In contrast, wounds in IL-10 knockout fetal skin grafts showed significant inflammation and scar formation.

CONCLUSIONS: Fetal skin grafts on adult syngeneic mice heal without inflammation or scar formation. The absence of IL-10 in fetal skin results in scar formation.Intrinsic lack of IL-10 may result in continued amplification of the inflammatory cytokine cascade, continued stimulation of fibroblasts, and abnormal collagen deposition. IL-10 is necessary for scarless wound repair to occur.

The potential role of insulin-like growth factors in skeletal muscle regeneration.

MacGregor J, Parkhouse WS. Metabolic Biochemistry Lab, School of Kinesiology, Simon Fraser University, Burnaby, BC.

Can J Appl Physiol 1996 Aug;21(4):236-50

The role of the insulin-like growth factors I and II (IGF-I and IGF-II), previously known as the somatomedins, in general growth and development of various tissues have been known for many years. Thought of exclusively as endocrine factors produced by the liver, and under the control of growth hormone, the somatomedins were known as the intermediaries by which growth hormone exerted its cellular effects during tissue growth and maturation. Eventually it was discovered that virtually every tissue type is capable of autocrine production of the IGFs, and their involvement in skeletal muscle tissue repair and regeneration became apparent. Recent advances in technology have allowed the characterisation of many of the different growth factors believed to play a role in muscle regeneration, and experimental manipulations of cells in culture have provided insight into the effects of the various growth factors on the myoblast. This paper explores the potential role of the IGFs in skeletal muscle regeneration. A critical role of IGF-II in terminal differentiation of proliferating muscle precurser cells following injury is proposed.

Effect of L-arginine on the course of experimental colitis.

Mane J, Fernandez-Banares F, Ojanguren I, Castella E, Bertran X, Bartoli R, Alvarez M, Gassull MA. Research Unit, Pathology, Department of Gastroenterology, Hospital Universitari Germans Trias i Pujol, Badalona, Spain.

Clin Nutr 2001 Oct;20(5):415-22

BACKGROUND AND AIMS: L-Arg is the substrate for nitric oxide, and also for L-ornithine which, in turn, is the precursor for the synthesis of collagen and polyamines. By these different metabolic pathways, L-Arg is involved in the mechanisms of inflammation, tissue repair and fibrosis. Thus, the aim of this study was to assess the effect of both different amounts of L-Arg supplementation and L-Arg-free diets upon colonic inflammatory damage and fibrosis in experimental colitis.

METHODS: Sprague-Dawley rats with trinitrobenzene sulphonic acid (TNBS)-induced colitis received increasing doses of L-Arg (30, 100, 500 mg/day), or D-Arg (500 mg/day). In a second experiment, two L-Arg-free diets (one supplemented with L-Gly) were compared to a L-Arg diet. Nitrite/nitrate release in the lumen of the colon and colonic damage were evaluated. In the first experiment, tissue collagen levels and colonic mucosal proliferation were also assessed.

RESULTS: In the acute phase of colitis, intracolonic nitrite/nitrate levels were significantly higher in the 100 and 500 mg supplemented L-Arg groups than in D-Arg group. However, only rats treated with 500 mg of L-Arg showed moderately higher inflammatory and fibrosis colonic scores than the D-Arg treated rats. There was no significant influence of L-Arg-free diets on the course of TNBS-induced colitis. However, L-Arg diet accelerated weight gain both pre- and post-TNBS.

CONCLUSIONS: These results suggest that normal amounts of L-Arg in the diet are not harmful, whereas both absence of L-Arg or supplementation with high doses of this amino acid may be deleterious. In the former this might be due to a decrease of nitrogen retention in injured rats, whereas in the latter it may result from both nitric oxide-mediated tissue damage and collagen deposition. Copyright 2001 Harcourt Publishers Ltd.

Bromelain: biochemistry, pharmacology and medical use.

Maurer HR. Department of Biochemistry, Molecular Biology and Biotechnology, Institute of Pharmacy, Freie Universitat Berlin, Germany. hrmaurer@zedat.fu-berlin.de

Cell Mol Life Sci 2001 Aug;58(9):1234-45

Bromelain is a crude extract from the pineapple that contains, among other components, various closely related proteinases, demonstrating, in vitro and in vivo, antiedematous, antiinflammatory, antithrombotic and fibrinolytic activities. The active factors involved are biochemically characterized only in part. Due to its efficacy after oral administration, its safety and lack of undesired side effects, bromelain has earned growing acceptance and compliance among patients as a phytotherapeutical drug. A wide range of therapeutic benefits has been claimed for bromelain, such as reversible inhibition of platelet aggregation, angina pectoris, bronchitis, sinusitis, surgical traumas, thrombophlebitis, pyelonephritis and enhanced absorption of drugs, particularly of antibiotics. Biochemical experiments indicate that these pharmacological properties depend on the proteolytic activity only partly, suggesting the presence of nonprotein factors in bromelain. Recent results from preclinical and pharmacological studies recommend bromelain as an orally given drug for complementary tumor therapy: bromelain acts as an immunomodulator by raising the impaired immunocytotoxicity of monocytes against tumor cells from patients and by inducing the production of distinct cytokines such as tumor necrosis factor-a, Interleukin (Il)-1beta, IL-6, and Il-8. In a recent clinical study with mammary tumor patients, these findings could be partially confirmed. Especially promising are reports on animal experiments claiming an antimetastatic efficacy and inhibition of metastasis-associated platelet aggregation as well as inhibition of growth and invasiveness of tumor cells. Apparently, the antiinvasive activity does not depend on the proteolytic activity. This is also true for bromelain effects on the modulation of immune functions, its potential to eliminate burn debris and to accelerate wound healing. Whether bromelain will gain wide acceptance as a drug that inhibits platelet aggregation, is antimetastatic and facilitates skin debridement, among other indications, will be determined by further clinical trials. The claim that bromelain cannot be effective after oral administration is definitely refuted at this time.

Proinflammatory mediators stimulate neutrophil-directed angiogenesis.

McCourt M, Wang JH, Sookhai S, Redmond HP. Department of Surgery, Professorial Unit, Cork University Hospital, Ireland. Arch Surg 1999 Dec;134(12):1325-31; discussion 1331-2

BACKGROUND: Vascular endothelial growth factor (VEGF; vascular permeability factor) is one of the most potent proangiogenic cytokines, and it plays a central role in mediating the process of angiogenesis or new blood vessel formation. Neutrophils (PMNs) recently have been shown to produce VEGF.

HYPOTHESIS: The acute inflammatory response is a potent stimulus for PMN-directed angiogenesis.

METHODS: Neutrophils were isolated from healthy volunteers and stimulated with lipopolysaccharide (LPS), tumor necrosis factor alpha (TNF-alpha), Interleukin 6 (IL-6), and anti-human Fas monoclonal antibody. Culture supernatants were assayed for VEGF using enzyme-linked immunosorbent assays. Culture supernatants from LPS- and TNF-alpha-stimulated PMNs were then added to human umbilical vein endothelial cells and human microvessel endothelial cells and assessed for endothelial cell proliferation using 5-bromodeoxyuridine labeling. Tubule formation was also assessed on MATRIGEL basement membrane matrix. Neutrophils were lysed to measure total VEGF release, and VEGF expression was detected using Western blot analysis.

RESULTS: Lipopolysaccharide and TNF-alpha stimulation resulted in significantly increased release of PMN VEGF (53249 and 48480 pg/mL, respectively; for all, presented as mean SEM) compared with control experiments (324 pg/mL). Interleukin 6 and Fas had no effect. Culture supernatants from LPS- and TNF-alpha-stimulated PMNs also resulted in significant increases (P<.005) in macrovascular and microvascular endothelial cell proliferation and tubule formation. Adding anti-human VEGF-neutralizing polyclonal antibody to stimulated PMN supernatant inhibited these effects. Total VEGF release following cell lysis and Western blot analysis suggests that the VEGF is released from an intracellular store.

CONCLUSION: Activated human PMNs are directly angiogenic by releasing VEGF, and this has important implications for inflammation, capillary leak syndrome, wound healing, and tumor growth.

Factors influencing wound healing after surgery for metastatic disease of the spine. McPhee IB; Williams RP; Swanson CE Division of Orthopaedic Surgery, University of Queensland, Brisbane, Australia.

Spine (UNITED STATES) Mar 15 1998 , 23 (6) p726-32; discussion 732-3,

The study group consisted of 53 patients who underwent 75 operations for spine metastases. Patient and tumor demographic factors, preoperative nutritional status, and perioperative adjunctive therapy were retrospectively reviewed.

OBJECTIVE: To determine the risk factors for wound breakdown and infection in patients undergoing surgery for spinal metastases.

SUMMARY OF BACKGROUND DATA: Spinal fusion using spine implants may be associated with an infection rate of 5% or more. Surgery for spine metastases is associated with an infection rate of more than 10%. Factors other than the type of surgery performed may account for the greater infection rate.

METHODS: Data were obtained by reviewing patient records. Age, sex, and neurologic status of the patient; tumor type and site; and surgical details were noted. Adjunctive treatment with corticosteroids and radiotherapy was recorded. Nutritional status was evaluated by determining serum protein and serum albumin concentrations and by total lymphocyte count.

RESULTS: Wound breakdown and infection occurred in 15 of 75 wounds. No patient or tumor demographic factors other than intraoperative blood loss (P < 0.1) were statistically associated with infection. The correlation between preoperative protein deficiency (P < 0.01) or perioperative corticosteroid administration (P < 0.10) and wound infection was significant. There was no statistical correlation between lymphocyte count or perioperative radiotherapy and wound infection.

CONCLUSIONS: The results indicate that preoperative protein depletion and perioperative administration of corticosteroids are risk factors for wound infection in patients undergoing surgery for spine metastases. Perioperative correction of nutritional depletion and cessation of steroid therapy may reduce wound complications.

Nitrogen retention, muscle creatine and orotic acid excretion in traumatized rats fed arginine and glycine enriched diets.

Minuskin ML, Lavine ME, Ulman EA, Fisher H.

J Nutr 1981 Jul;111(7):1265-74

Male, Sprague-Dawley rats were subjected to the trauma of laparotomy under sodium pentothal anesthesia. Apparent N retention (N intake - Urinary N) was studied when these rats were fed a 25% casein diet either unsupplemented or enriched with arginine plus glycine or with ornithine plus glycine. These amino acids occur in particularly high concentrations in skin and connective tissue and might, therefore, be required in greater amounts for tissue repair. In one experiment muscle creatine content and orotic acid excretion in the urine were determined. We found that laparotomy carried out under sodium pentothal anesthesia was a highly reproducible form of trauma which resulted in a significant decrease in apparent N retention. Supplementing a 25% casein based diet with arginine and glycine significantly improved apparent N retention both in untraumatized as well as in traumatized rats. Ornithine was less effective than arginine in improving apparent N retention. Urinary orotic acid excretion was significantly increased in rats fed the unsupplemented casein diet, regardless of the imposition of trauma. Muscle creatine content was significantly increased by the supplementation of the diet with arginine plus glycine. The beneficial effect of arginine-plus-glycine enrichment in traumatized rats does not appear to be due to an arginine deficit needed for the detoxification of ammonia from excess amino acids but may be related to creatine synthesis and turnover.

[The effect of superoxide dismutase on the inflammation induced by periodontal pathogenic bacteria and wound healing of gingival incision] [Article in Japanese]

Misaki H, Suzuki M, Yoshie H, Hara K. Department of Periodontology, Niigata University.

Nippon Shishubyo Gakkai Kaishi 1990 Mar;32(1):93-110

The therapeutic effect of superoxide dismutase (SOD) and the role of O2- were assessed on 3 groups of Wistar rats (total 115). Fifty-four received injections of gingival bacteria or of anaerobically cultured rat dental plaque in their peritoneum, then received both intravenous (i.v.) and intraperitoneal (i.p.) injection of SOD. The rats were killed 48 hours later to collect their peritoneal exudate for cell count and for acid phosphatase activity assessment. Twenty-six received injections of bacteria in their footpads, after which SOD was administered intravenously. These rats were killed at 6 hours, 48 hours and 1 week respectively for histological examination. The gingiva of 26 rats were incised to create artificial lesions. The rats were killed at 24 or 48 hours and examined histologically. The nine remaining rats were used as controls (untreated) for the 3 experiments. The results of the 3 experiments showed that: Injection of SOD reduced exudation and acid phosphatase activity enhanced by the injection of B. gingivalis, at dosages of 1, 5 mg/kg i.p. and 5 mg/kg i.v., but 10 mg/kg i.p. had no apparent effect; i.v. injection of SOD had inhibitory effects on cell infiltration of B. gingivalis into the footpad, and the increase in fibrin and fibroblast formation through time was greater in SOD-administered rats; a decreased cell infiltration rate and increased fibrin network, fibroblast proliferation and gingival tissue regeneration occurred in specimens with artificial lesions given SOD. Apparently SOD has a curative effect on both inflammatory reaction induced by B. gingivalis and periodontal wound healing.

Exogenously regulated stem cell-mediated gene therapy for bone regeneration.

Moutsatsos IK, Turgeman G, Zhou S, Kurkalli BG, Pelled G, Tzur L, Kelley P, Stumm N, Mi S, Muller R, Zilberman Y, Gazit D. Molecular Pathology Laboratory, Hebrew University-Hadassah Medical and Gene Therapy Center, Jerusalem, Israel.

Mol Ther 2001 Apr;3(4):449-61

Regulated expression of transgene production and function is of great importance for gene therapy. Such regulation can potentially be used to monitor and control complex biological processes. We report here a regulated stem cell-based system for controlling bone regeneration, utilizing genetically engineered mesenchymal stem cells (MSCs) harboring a tetracycline-regulated expression vector encoding the osteogenic growth factor human BMP-2. We show that doxycycline (a tetracycline analogue) is able to control hBMP-2 expression and thus control MSC osteogenic differentiation both in vitro and in vivo. Following in vivo transplantation of genetically engineered MSCs, doxycycline administration controlled both bone formation and bone regeneration. Moreover, our findings showed increased angiogenesis accompanied by bone formation whenever genetically engineered MSCs were induced to express hBMP-2 in vivo. Thus, our results demonstrate that regulated gene expression in mesenchymal stem cells can be used as a means to control bone healing.

Spatial and temporal gene expression in chondrogenesis during fracture healing and the effects of basic fibroblast growth factor.

Nakajima F, Ogasawara A, Goto K, Moriya H, Ninomiya Y, Einhorn TA, Yamazaki M. Department of Orthopaedic Surgery, Chiba University School of Medicine, Japan.

J Orthop Res 2001 Sep;19(5):935-44

Chondrogenesis is an essential component of endochondral fracture healing, though the molecular and cellular events by which it is regulated have not been fully elucidated. In this study, we used a rat model of closed fracture healing to determine the spatial and temporal expression of genes for cartilage-specific collagens. Furthermore, to determine the effects of basic fibroblast growth factor (bFGF) on chondrogenesis in fracture healing, we injected 100 microg recombinant human bFGF into the fracture site immediately after fracture. In normal calluses, pro-alpha1(II) collagen mRNA (COL2A1) was detected in proliferative chondrocytes beginning on day 4 after the fracture, and pro-alpha1(X) collagen mRNA (COL10A1) in hypertrophic chondrocytes beginning on day 7. In FGF-injected calluses, the cartilage enlarged in size significantly. On day 14, both COL2A1- and COL10A1-expressing cells were more widely distributed, and the amounts of COL2A1 and COL10A1 mRNAs were both approximately 2-fold increased when compared with uninjected fractures. Temporal patterns of expression for these genes were, however, identical to those found in normal calluses. The number of proliferating cell nuclear antigen-positive cells was increased in the non-cartilaginous area in the bFGF-injected calluses by day 4. The present molecular analyses demonstrate that a single injection of bFGF enhances the proliferation of chondroprogenitor cells in fracture callus, and thus contributes to the formation of a larger cartilage. However, maturation of chondrocytes and replacement of the cartilage by osseous tissue are not enhanced by exogenous bFGF, and this results in the prolonged cartilaginous callus phase. We conclude that, in the healing of closed fractures of long bones, exogenous bFGF has a capacity to enlarge the cartilaginous calluses, but not to induce more rapid healing.

Lipid peroxides and superoxide dismutase (SOD) induction in skin inflammatory diseases, and treatment with SOD preparations.

Niwa Y. Niwa Institute for Immunology, Kochi-Ken, Japan.

Dermatologica 1989;179 Suppl 1:101-6

In the skin ulcer or severely inflamed and erosive lesions induced due to burn, wounds and other dermatitides, lipid peroxides were markedly increased, with resultant cytotoxic effects in situ. Generally, superoxide dismutase (SOD), which scavenges oxygen radicals or inhibits lipid peroxidation, is adapted to be induced (increased) under oxygen toxicity. For the treatment of not only systemic inflammatory diseases but also skin ulcer lesions, especially due to burn and wounds, liposomal-encapsulated SOD injection was effective. Topical application of free Mn-SOD or Cu, Zn-SOD extracted from bovine, bacterial and other species except for human was also dramatically effective in skin lesions; a burnt patient who was advised to undergo skin transplantation showed complete healing with free SOD cream. In addition, topical application of low molecular weight antioxidants, AOA or Bio-harmony, also showed remarkable effectiveness in these skin lesions. However, SOD dissolved in the vehicle containing greater amounts of vaselinum album (white petrolatum) rapidly lost its activity, and that dissolved in the vehicle with large quantities of water lost its activity within 3 months. In conclusion, SOD should be dissolved in the vehicle before use, however, low molecular weight antioxidant cream can be commercially sold because it does not lose its activity for long periods.

A comparison of topical honey and phenytoin in the treatment of chronic leg ulcers.

Oluwatosin OM, Olabanji JK, Oluwatosin OA, Tijani LA, Onyechi HU. Department of Surgery, University College Hospital, Ibadan, Nigeria.

Afr J Med Med Sci 2000 Mar;29(1):31-4

In view of the reports that phenytoin and honey are useful in the healing of wounds, a comparison of their topical use in the treatment of chronic leg ulcers was carried out. Fifty cases of chronic leg ulceration were studied, each for a period of four weeks. They were assigned into three groups for honey, phenytoin/honey mixture, and phenytoin topical treatment. Overall mean duration of the ulcers was 56.5 months while the mean(s.d.) size was 3339 (5193) mm2. Mean percent reduction in size in the group treated with honey, 27.0 (36.9), was not significantly different (H = 0.26; 2 df; p = 0.88) from that of the mixture group, which was 25.9 (46.4), and from that of the phenytoin group which was 35.5 (53.2). This percent reduction in size was significantly greater, (H = 7.69; 2 df; P = 0.02), during the first week in the phenytoin group than in the other groups. Four of the cases progressed to complete healing at the end of four weeks with phenytoin. Pain score difference (using a graduation scale from 0 to 10) at the end of the four week treatment, was, 1.8 (1.7) in honey group, 2.0 (1.3) in mixture group and 3.6 (2.4) in phenytoin group. This difference was not significant, (H = 3.09; 2 df; P = 0.21). Our study suggests that phenytoin may be superior to honey as a topical agent in the treatment of chronic ulcers.

The musculoskeletal effects of smoking.

Porter SE, Hanley EN Jr. Department of Orthopaedic Surgery, Carolinas Medical Center, Charlotte, NC 28323, USA.

J Am Acad Orthop Surg 2001 Jan-Feb;9(1):9-17

Currently, there are more than 50 million smokers in this country, and approximately 800 billion cigarettes are smoked each year. Smoking is now the leading avoidable cause of morbidity and mortality in the United States. According to one report, over 500,000 deaths per year in the United States alone can be attributed to smoking. For years, orthopaedic surgeons have known about the relationships that putatively exist between smoking and an array of orthopaedic conditions and complications. It has been shown to adversely affect bone mineral density, lumbar disk disease, the rate of hip fractures, and the dynamics of bone and wound healing. Although scientific and clinical information on smoking and its consequences suggests differing degrees of correlation between smoking and orthopaedic conditions, most available data do suggest a real and reproducible relationship. In the past, there have been many individual reports that deal with these relationships separately but very few published comprehensive reviews. This summary of the current literature regarding the relationship between smoking and musculoskeletal diseases and their treatment provides information that can be used clinically by both the practitioner and the patient.

Local application of growth factors (insulin-like growth factor-1 and transforming growth factor-beta1) from a biodegradable poly(D,L-lactide) coating of osteosynthetic implants accelerates fracture healing in rats.

Schmidmaier G, Wildemann B, Bail H, Lucke M, Fuchs T, Stemberger A, Flyvbjerg A, Haas NP, Raschke M. Department of Trauma and Reconstructive Surgery, Charite, Humboldt University of Berlin, Berlin, Germany. gerhard.schmidmaier@charite.de

Bone 2001 Apr;28(4):341-50

In vitro and in vivo studies have demonstrated an osteoinductive effect of growth factors such as insulin-like growth factor-1 (IGF-1) and transforming growth factor-beta1 (TGF-beta1). However, for therapeutic use in fracture treatment, questions remain with regard to the local application of these proteins. A controlled, local release of growth factors from a biodegradable polylactide coating of osteosynthetic implants may have a stimulating effect on fracture healing. Such implants could stabilize the fracture and their bioactive surface could function simultaneously as a local drug-delivery system. Previous studies have demonstrated the high mechanical stability of an approximately 10-14-&amp;mgr;m-thick poly(D,L-lactide) (PDLLA) coating on metallic implants, which can even withstand the process of intramedullary insertion. Following an initial peak, 80% of incorporated growth factors IGF-1 and TGF-beta1 were continuously released within 42 days. The effect of locally applied IGF-1 and TGF-beta1 from a biodegradable PDLLA coating of intramedullary implants on fracture healing was investigated in a rat model. Midshaft fractures of the right tibia of 5-month-old female Sprague-Dawley rats (n = 127) were stabilized with coated vs. uncoated titanium Kirschner wires. X-ray examinations and blood analyses were performed, and body weight and body temperature measurements were taken throughout the experimental period. After 28 and 42 days, respectively, tibiae were dissected for mechanical torsional testing and histomorphometrical analyses. X-rays demonstrated an almost completely consolidated fracture, biomechanical testing showed a significantly higher maximum load and torsional stiffness, and histological and histomorphometric analyses demonstrated progressed remodeling after 28 and 42 days in the group treated with growth factors as compared with controls. Interestingly, the PDLLA coating itself revealed a positive effect on fracture healing even without incorporated growth factors. No systemic changes of serum parameters, including IGF-1 and IGF binding proteins, and no differences in body weight and body temperature were observed within and between groups. These findings suggest that the local application of growth factors from a biodegradable PDLLA coating of osteosynthetic implants accelerates fracture healing significantly without systemic side effects.

Asiaticoside-induced elevation of antioxidant levels in healing wounds.

Shukla A, Rasik AM, Dhawan BN Pharmacology Department, Central Drug Research Institute, Lucknow, India. gshukla@zoo.uvm.edu

Phytother Res 1999 Feb;13(1):50-4

Asiaticoside derived from the plant Centella asiatica is known to possess good wound healing activity. Enhanced healing activity has been attributed to increased collagen formation and angiogenesis. Since antioxidants have been reported to play a significant role in the wound healing process we studied the effect of asiaticoside on the levels of certain antioxidants in the wound so as to explore the possible involvement of such a mechanism in the asiaticoside induced wound healing. Asiaticoside application (0.2%, topical) twice daily for 7 days to excision-type cutaneous wounds in rats led to increased enzymatic and non-enzymatic antioxidants, namely superoxide dismutase (35%), catalase (67%), glutathione peroxidase (49%), vitamin E (77%) and ascorbic acid (36%) in newly formed tissues. It also resulted in a several fold decrease in lipid peroxide levels (69%) as measured in terms of thiobarbituric acid reactive substance. However, continued application for 14 days showed no significant difference in these antioxidants compared with their values in vehicle treated wound tissue. It appears from the present study that asiaticosides enhanced induction of antioxidant levels at an initial stage of healing which may be an important contributory factor in the healing properties of this substance.

In vitro and in vivo wound healing activity of asiaticoside isolated from Centella asiatica.

Shukla A, Rasik AM, Jain GK, Shankar R, Kulshrestha DK, Dhawan BN. Pharmacology Division, Central Drug Research Institute, Lucknow, India. gshukla@zoo.uvm.edu1

J Ethnopharmacol 1999 Apr;65(1):1-11

The activity of asiaticoside, isolated from Centella asiatica, has been studied in normal as well as delayed-type wound healing. In guinea pig punch wounds topical applications of 0.2% solution of asiaticoside produced 56% increase in hydroxyproline, 57% increase in tensile strength, increased collagen content and better epithelisation. In streptozotocin diabetic rats, where healing is delayed, topical application of 0.4% solution of asiaticoside over punch wounds increased hydroxyproline content, tensile strength, collagen content and epithelisation thereby facilitating the healing. Asiaticoside was active by the oral route also at 1 mg/kg dose in the guinea pig punch wound model. It promoted angiogenesis in the chick chorioallantoic membrane model at 40 microg/disk concentration. These results indicate that asiaticoside exhibits significant wound healing activity in normal as well as delayed healing models and is the main active constituent of Centella asiatica.

Curcumin enhances wound healing in streptozotocin induced diabetic rats and genetically diabetic mice.

Sidhu GS, Mani H, Gaddipati JP, Singh AK, Seth P, Banaudha KK, Patnaik GK, Maheshwari RK. Center for Combat and Life Sustainment Research, Uniformed Services University of Health Sciences, Bethesda, MD 20814, USA. rmaheshwari@usuhs.mil

Wound Repair Regen 1999 Sep-Oct;7(5):362-74

Tissue repair and wound healing are complex processes that involve inflammation, granulation and tissue remodeling. Interactions of different cells, extracellular matrix proteins and their receptors are involved in wound healing, and are mediated by cytokines and growth factors. Previous studies from our laboratory have shown that curcumin (diferuloylmethane), a natural product obtained from the rhizomes of Curcuma longa, enhanced cutaneous wound healing in rats and guinea pigs. In this study, we have evaluated the efficacy of curcumin treatment by oral and topical applications on impaired wound healing in diabetic rats and genetically diabetic mice using a full thickness cutaneous punch wound model. Wounds of animals treated with curcumin showed earlier re-epithelialization, improved neovascularization, increased migration of various cells including dermal myofibroblasts, fibroblasts, and macrophages into the wound bed, and a higher collagen content. Immunohistochemical localization showed an increase in transforming growth factor-beta1 in curcumin-treated wounds compared to controls. Enhanced transforming growth factor-beta1 mRNA expression in treated wounds was confirmed by in situ hybridization, and laser scan cytometry. A delay in the apoptosis patterns was seen in diabetic wounds compared to curcumin treated wounds as shown by terminal deoxynucleotidyl transferase-mediated deoxyuridyl triphosphate nick end labeling analysis. Curcumin was effective both orally and topically. These results show that curcumin enhanced wound repair in diabetic impaired healing, and could be developed as a pharmacological agent in such clinical settings.

Nitrogen retention in rats fed on diets enriched with arginine and glycine. 1. Improved N retention after trauma.

Sitren HS, Fisher H.

Br J Nutr 1977 Mar;37(2):195-208

1. Nitrogen retention was measured in adult rats (250-350 g) subjected to the trauma of hind-leg fracture and given diets with or without arginine plus glycine supplementation. Observations were also recorded on excretion of creatine, creatinine, allantoin, and orotic acid. Liver and skeletal muscle transaminase activities were also determined. 2. When traumatized rats weighing approximately 250 g were given a diet with 200 g casein/kg, supplemented with 20 g arginine and 10 g glycine/kg (EC diet) or a casein diet made isonitrogenous with the EC diet by addition of aspartic acid (C diet), a 60-70% increase in N retention was observed for the first 5 d post-injury for animals consuming the EC diet. A soya-bean (S) diet, isonitrogenous to the diet containing 20% casein, supplemented with arginine and glycine was as effective as the EC diet in promoting significantly better N retention of traumatized rats (350 g) in comparison to rats given the C diet. 3. When the dietary casein content was reduced to 100 g/kg, supplements of 10 g arginine and 5 g glycine or 20 g arginine and 10 g glycine/kg did not improve N retention. It is suggested that both protein quality and protein quantity are important following injury. 4. An increased excretion of creatine was observed in traumatized rats given the high-protein diets supplemented with arginine and glycine. No consistent changes were noted for urine creatinine. 5. 5. Urine allantoin levels remained stable after leg-fracture in rats consuming either the C or EC diets. Differences in the levels of urine orotic acid were found during both the pre- and post-injury periods in rats given the C, EC or S diets. 6. The mechanisms responsible for the improved N retention of traumatized rats consuming the high-protein diets with supplements of arginine and glycine may be related to the role of arginine both as a constituent of muscle tissue and as an intermediate in the urea cycle. 7. In traumatized rats fed the C or EC diets, liver transaminase activity increased whereas the transaminase activity in skeletal muscle decreased. These results support the recent concept that the increased excretion of N following injury arises from diminished reutilization of amino acids by muscle tissue without an acute increase in the rate of muscle catabolism.

Cyclic mechanical stretching enhances secretion of Interleukin 6 in human tendon fibroblasts.

Skutek M, van Griensven M, Zeichen J, Brauer N, Bosch U. Laboratory of Histology and Cell Biology, Department of Traumasurgery, Hanover Medical School, 30623 Hanover, Germany. skutek@aol.com

Knee Surg Sports Traumatol Arthrosc 2001 Sep;9(5):322-6

Accelerated rehabilitation after tendon and ligament injuries is widely accepted to avoid adverse effects of immobilization. However, progressive rehabilitation may also lead to an excessive inflammatory soft tissue response. To investigate the amount of loading necessary to accelerate the healing process without causing damage to the healing tissue, we experimentally stretched human tendon fibroblasts of healthy tendons 15 and 60 min with 1 Hz and an elongation of 5% and measured the secretion of Interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta1 (TGF-beta1), platelet-derived growth factor (PDGF), and fibroblast growth factor basic (bFGF). Secretion of IL-6 was significantly induced by 15 min of cyclic biaxial mechanical stretching after 4 and 8 h observation time and by 60 min stretching and 2 h observation time. The growth factors TGF-beta1, bFGF, and PDGF were secreted by human tendon fibroblasts both in stretched cells and controls; however, no increases were related to mechanical stretching. There was no measurable secretion of TNF-alpha in human tendon fibroblasts. These findings suggest that the inflammatory reaction often seen during physiotherapy after tendon and ligament injuries is caused in part by secretion of IL-6 from the stretched human tendon fibroblasts. IL-6 may cause exaggerated proliferation of fibroblasts and synovial cells as seen in rheumatoid arthritis and arthrofibrosis. However, physiological proliferative reactions leading to repair of injured tissue are also possible. IL-6 measured in the synovial fluid may be an important predictor for monitoring and improving therapeutic strategies in terms of tendon/ligament healing.

Spinal fusion with recombinant human growth and differentiation factor-5 combined with a mineralized collagen matrix.

Spiro RC, Thompson AY, Poser JW. Department of Research, Orquest, Inc., Mountain View, California 94043, USA. rspiro@fibrogen.com

Anat Rec 2001 Aug 1;263(4):388-95

The availability of recombinant osteoinductive growth factors and new osteoconductive matrices offers an alternative to the use of autogenous bone (autograft) for grafting indications. This study evaluates the bone-forming activity of a mineralized collagen matrix combined with recombinant human growth and differentiation factor-5 in a rabbit posterolateral spinal fusion model. The activity of three distinct matrix-growth factor formulations is assessed by radiographic, histologic, and mechanical strength methods. Results show that the radiographic density, histologic quality, and mechanical strength of fusion at 12 weeks post-treatment rank consistently within the treatment groups. Optimal formulations are shown to perform similar to autograft in both the rate and strength of fusion. Fusion rates as high as 80% are observed within specific matrix/growth factor formulations. The average biomechanical strength of treated motion segments in the most efficacious formulation is 82% higher than that obtained with autograft, although this difference is not statistically significant. The fusion mass formed in response to matrix/growth factor formulations is composed of normal trabecular bone with a thin outer cortical plate and modest hematopoietic bone marrow. These results demonstrate that the combination of a mineralized collagen matrix with recombinant human growth and differentiation factor-5 maximizes the inherent conductive and inductive properties of each component, respectively, to provide an effective alternative to autograft for bone grafting procedures. Copyright 2001 Wiley-Liss, Inc.

Interleukin-6 promotes post-traumatic healing in the central nervous system.

Swartz KR, Liu F, Sewell D, Schochet T, Campbell I, Sandor M, Fabry Z. Department of Neurological Surgery, University of Wisconsin, Madison 53706, USA.

Brain Res 2001 Mar 30;896(1-2):86-95

The central nervous system (CNS) is an immune-privileged site where the role of immune cells and mediators in traumatic brain injury is poorly understood. Previously we have demonstrated that Interleukin (IL)-6, a cytokine that acts on a wide range of tissues influencing cell growth and differentiation, is an agonist for vascular endothelial growth factor (VEGF), in in vitro vascularization assays for brain microvessel endothelial cells. In this present work we focus on the role of IL-6 in promoting tissue repair in the CNS in vivo. An aseptic cerebral injury (ACI) was created in the right parietal cortex, using both wild type (C57Bl/6J) and IL-6-deficient (C57Bl/6J-IL-6-/-) mice to study the consequences of the absence of IL-6 on the pathology of brain injuries. We monitored the immediate, early, and late responses to this traumatic injury by characterizing several histologic features in the CNS at days 1, 4, 7 and 14 following injury. Acellular necrosis, cellular infiltration, and re-vascularization were characterized in the injured tissues, and each of these histologic features was individually graded and totaled to assign a healing index. IL-6-deficient mice were found to have a comparatively slower rate of recovery and healing. Furthermore, fluorescein isothiocyanate (FITC)-dextran intravenous injection demonstrated leaky vessels in IL-6-deficient but not in wild type animals following ACI. Additionally, chronic expression of IL-6 in the CNS using transgenic GFAP-IL-6 mice resulted in more rapid healing following ACI. The accelerated tissue repair in GFAP-IL-6 transgenic animals is primarily due to extensive re-vascularization as detected by endothelial cell markers. Combined, this data suggests an important role of IL-6 in tissue repair processes following traumatic injury in the CNS.

Use of magnet therapy to heal an abdominal wound: a case study.

Szor JK; Topp R Toledo Hospital, Ohio, USA.

Ostomy Wound Manage (United States) May 1998 , 44 (5) p24-9 Complementary therapies, in particular magnet therapy, may have benefits to offer in healing chronic wounds. This case study involves a 51 year old paraplegic woman with an abdominal wound that had been present for one year. Traditional approaches to wound care had not achieved complete healing. Prior to surgical intervention, the patient consented to the application of magnet therapy over her usual wound dressing. In one month, the wound completely healed. On the basis of this case, further investigation of magnet therapy for wound healing appears to be warranted.

Role of phenytoin in wound healing--a wound pharmacology perspective.

Talas G, Brown RA, McGrouther DA. Department of Plastic and Reconstructive Surgery, University College London Medical School, UK. rmhkgyt@ucl.ac.uk

Biochem Pharmacol 1999 May 15;57(10):1085-94

Topical agents used for the enhancement of wound healing are designed to act locally and, therefore, do not undergo classic systemic metabolic modification. This commentary reviews the potential role of a vulnerary agent, phenytoin, (PHT), from a wound pharmacology perspective. This agent may have the potential to alter the dynamics of wound healing, suggesting a therapeutic use for the stimulation of chronic wounds. Oral PHT therapy is used widely for the treatment of convulsive disorders, and about half the patients treated develop gingival overgrowth as a side-effect. This apparent stimulatory effect has prompted its assessment in wound healing. Investigations into the mechanisms of gingival overgrowth also provide clues to its action in wound healing, and important similarities and differences are discussed. It appears also that both gingiva and skin are important extrahepatic sites for xenobiotic metabolism, and analysis of the biochemical mechanisms should lead to the design of safer analogues for wound healing. On the other hand, differences between the pharmacokinetics of topical PHT in these tissue situations indicate that different formulations are required for gingival and cutaneous wound healing and during the changing course of wound healing itself.

In vitro modulation of keratinocyte wound healing integrins by zinc, copper and manganese.

Tenaud I, Sainte-Marie I, Jumbou O, Litoux P, Dreno B. Laboratory of Immuno-Dermatology, CHU Hotel-Dieu, Place A. Ricordeau, 44035 Nantes Cedex 01, France.

Br J Dermatol 1999 Jan;140(1):26-34

Although the trace elements zinc, copper and manganese are used in vivo for their healing properties, their mechanism of action is still only partially known. Some integrins expressed by basal layer keratinocytes play an essential part in healing, notably alpha2beta1, alpha3beta1, alpha6beta4 and alphaVbeta5, whose expression and distribution in epidermis are modified during the re-epithelialization phase. This study demonstrates how the expression of these integrins are modulated in vitro by trace elements. Integrin expression was studied in proliferating keratinocytes in monolayer cultures and in reconstituted skin that included a differentiation state. After 48 h incubation with zinc gluconate (0.9, 1.8 and 3.6 microg/mL), copper gluconate (1, 2 and 4 microg/mL), manganese gluconate (0.5, 1 and 2 microg/mL) and control medium, integrin expression was evaluated by FACScan and immunohistochemistry. Induction of alpha2, alpha3, alphaV and alpha6 was produced by zinc gluconate 1.8 microg/mL in monolayers, of alpha2, alpha6 and beta1 by copper gluconate 2 and 4 microg/mL and of all the integrins studied except alpha3 by manganese gluconate 1 microg/mL. Thus, alpha6 expression was induced by all three trace elements. The inductive effect of zinc was particularly notable on integrins affecting cellular mobility in the proliferation phase of wound healing (alpha3, alpha6, alphaV) and that of copper on integrins expressed by suprabasally differentiated keratinocytes during the final healing phase (alpha2, beta1 and alpha6), while manganese had a mixed effect.

Bioactivity of the vascular endothelial growth factor trapped in fibrin clots: production of IL-6 and IL-8 in monocytes by fibrin clots.

Tezono K, Sarker KP, Kikuchi H, Nasu M, Kitajima I, Maruyama I. Second Department of Internal Medicine, Oita Medical University, Oita, Japan.

Haemostasis 2001 Mar-Apr;31(2):71-9

The blood coagulation cascade is activated following vascular-wall injury. The serine protease thrombin is the final protease in this cascade that causes the formation of fibrin from fibrinogen. Thrombin also causes the activation of platelets, which are trapped in a fibrin net followed by hemostasis. Platelets gathered into fibrin clots release several growth factors such as platelet-derived growth factor and transforming growth factor beta. In the present study, we demonstrated that the vascular endothelial growth factor (VEGF) could be bound to fibrin clots in the plasma, and that incubation of the endothelial cells with these VEGF-bound fibrin clots induced proliferation of endothelial cells. Thus, it suggests that clot-bound VEGF may play a role in wound healing through the proliferation of endothelial cells and vascular smooth-muscle cells. On the other hand, a noticeable migration of monocytes was observed when they were cultured on dishes in the presence of VEGF-bound fibrin clots. Moreover, peripheral blood monocytes incubated in the presence of VEGF-bound fibrin clots strikingly increased the production of IL-6 and IL-8, demonstrating that VEGF trapped in fibrin clots not only induces proliferation of human umbilical vein endothelial cells and migration of monocytes but also enhances secretion of IL-6 and IL-8. Thus, our data suggest that fibrin clots that contain several growth factors act as a bioactive reservoir and may play an important role in hemostasis as well as wound healing. Copyright 2001 S. Karger AG, Basel

Inability of transforming growth factor-beta 1, combined with a bioabsorbable polymer paste, to promote healing of bone defects in the rat distal femur.

Tielinen L, Manninen M, Puolakkainen P, Kellomaki M, Tormala P, Rich J, Seppala J, Rokkanen P. Department of Orthopaedics and Traumatology, Helsinki University Central Hospital, Topeliuksenkatu 5, 00260 Helsinki, Finland. Laura.Tielinen@hus.fi

Arch Orthop Trauma Surg 2001;121(4):191-6

The ability of transforming growth factor-beta 1 (TGF-beta 1) to promote bone formation suggests that it may have potential as a therapeutic agent in bone defects. However, there still exists a need for an effective method of delivering TGF-beta 1 to the site of an osseous defect. In the present study, TGF-beta 1 was embedded in a bioabsorbable polymer paste (a blend of an L-lactide oligomer and a copolymer of epsilon-caprolactone and DL-lactide). The release of TGF-beta 1 from the polymer paste was examined in vitro with an enzyme-linked immunosorbent assay, which showed sustained release of active TGF-beta 1 over a 7-day period. Further, the polymer paste was used to fill a bone defect in the rat distal femur. The amount of TGF-beta 1 per rat was 50 micrograms, while in a control group we used an identical polymer paste without the growth factor. After a follow-up of 1 week and 3 weeks, the femurs were examined radiographically, histologically, histomorphometrically, microradiographically, and were also used for tetracycline-labeling studies. TGF-beta 1 did not enhance healing of the bone defect. A combination of growth factors would probably be a more potent osteoinductor than TGF-beta 1 alone.

Prospects for epidermal growth factor in the management of corneal disorders.

Tripathi RC, Raja SC, Tripathi BJ. Department of Ophthalmology and Visual Science, University of Chicago, Illinois.

Surv Ophthalmol 1990 May-Jun;34(6):457-62

Epidermal growth factor (EGF) is a naturally occurring mitogen which, in its recombinant form, is under intensive investigation for therapeutic use. Receptor activation by EGF induces up-regulation of synthesis of specific proteins as well as proliferation and differentiation of the corneal epithelium, keratocytes, and endothelium both in vivo and in vitro. With topical application of EGF, corneal wounds could possibly heal within hours, and the strength of the stromal scars is also increased; this may lead to the prospect of sutureless surgery. It may be possible to treat degenerative and dystrophic disorders of the cornea, especially of the endothelium, and to enhance the density of endothelial cells in donor corneas prior to transplantation. Combination therapy with EGF, fibroblast growth factor, and corticosteroids may be advantageous in producing a synergistic effect. It is possible that, with increased knowledge of the pharmacokinetics and the development of appropriate delivery systems, EGF could become an integral part of the next generation of ophthalmic pharmaceuticals.

[Improvement in the healing of colonic anastomoses by vitamin B5 and C supplements. Experimental study in the rabbit] [Article in French]

Vaxman F, Chalkiadakis G, Olender S, Maldonado H, Aprahamian M, Bruch JF, Wittmann T, Volkmar P, Grenier JF. Service de Chirurgie Digestive et Generale B, Hospices Civils de Strasbourg.

Ann Chir 1990;44(7):512-20

To study the effects of vitamins B5 and C on the healing process of colonic anastomoses, 3 groups of 20 rabbits were given daily either placebo (group A), or vitamin B5 (100 mg/kg: group B) or vitamin C (100 mg/kg: group C). After 8 days of supplementation, via a midline incision and under general anaesthesia, 2 colonic segments were removed, and the continuity was restored. On the 3rd post-operative day, the rabbits were killed and the anastomoses were removed. Mechanical properties of both normal colon and anastomoses were determined by using bursting pressure tests, number of burst anastomoses, fibroblast count, hydroxyproline concentration and determination by microanalysis of trace element content: Mg, P, S, Ca, Fe, Cu, Zn and Mn. Vitamin B5 (p = 0.03) and vitamin C (p less than 0.01) both decreased the number of burst anastomoses. Furthermore the required bursting pressure values were higher with vitamin C (p = 0.01) than in controls. Both vitamins restored normal Zn levels at the anastomotic site, whereas these levels decreased on the 3rd post-operative day during the normal healing process of colonic anastomosis. Moreover, vitamins B5 and C increased Fe, Cu and Mn levels, which are intimately all involved in collagen synthesis. Vitamins B5 and C enhance the colonic wound healing process in the rabbit, acting together in synergy in vivo as well as in vitro, as previously demonstrated.

Effect of pantothenic acid and ascorbic acid supplementation on human skin wound healing process. A double-blind, prospective and randomized trial.

Vaxman F, Olender S, Lambert A, Nisand G, Aprahamian M, Bruch JF, Didier E, Volkmar P, Grenier JF. INSERM U 61, Hospices Civils, Strasbourg, France.

Eur Surg Res 1995;27(3):158-66

This study aimed at testing human skin wound healing improvement by a 21-day supplementation of 1.0 g ascorbic acid (AA) and 0.2 g pantothenic acid (PA). 49 patients undergoing surgery for tattoos, by the successive resections procedure, entered a double-blind, prospective and randomized study. Tests performed on both skin and scars determined: hydroxyproline concentrations, number of fibroblasts, trace element contents and mechanical properties. In the 18 supplemented patients, it was shown that in skin (day 8) Fe increased (p < 0.05) and Mn decreased (p < 0.05); in scars (day 21), Cu (p = 0.07) and Mn (p < 0.01) decreased, and Mg (p < 0.05) increased; the mechanical properties of scars in group A were significantly correlated to their contents in Fe, Cu and Zn, whereas no correlation was shown in group B. In blood, AA increased after surgery with supplementation, whereas it decreased in controls. Although no major improvement of the would healing process could be documented in this study, our results suggest that the benefit of AA and PA supplementation could be due to the variations of the trace elements, as they are correlated to mechanical properties of the scars.

Studies on wound healing: effects of calcium D-pantothenate on the migration, proliferation and protein synthesis of human dermal fibroblasts in culture.

Weimann BI, Hermann D. F. Hoffmann-La Roche Ltd, Vitamins Division, Basel, Switzerland.

Int J Vitam Nutr Res 1999 Mar;69(2):113-9

The effect of calcium D-pantothenate on the migration, proliferation and protein synthesis of human dermal fibroblasts from three different donors was investigated. The migration of cells into a wounded area was dose-dependently stimulated by Ca D-pantothenate. The number of cells that migrated across the edge of the wound increased from 32 +/- 7 cells/mm without Ca D-pantothenate to 76 +/- 2 cells/mm with 100 mg/ml Ca D-pantothenate. Moreover, the mean migration distance per cell increased from 0.23 +/- 0.05 mm to 0.33 +/- 0.02 mm. The mean migration speed was calculated to be 10.5 mm/hour without and 15 mm/hour with Ca D-pantothenate. Cell proliferation was also dose-dependently stimulated. The final cell densities were 1.2 to 1.6-fold higher in cultures containing 100 mg/ml Ca D-pantothenate. The protein synthesis was modulated, since two unidentified proteins were more strongly expressed in pantothenate supplemented cultures. In conclusion, Ca D-pantothenate accelerates the wound healing process by increasing the number of migrating cells, their distance and hence their speed. In addition, cell division is increased and the protein synthesis changed. These results suggest that higher quantities of pantothenate are locally required to enhance wound healing.

EGF receptor.

Wells A. Department of Pathology, University of Alabama, Birmingham 35294-0007, USA. wells@uab.edu

Int J Biochem Cell Biol 1999 Jun;31(6):637-43

The receptor for the epidermal growth factor (EGF) and related ligands (EGFR), the prototypal member of the superfamily of receptors with intrinsic tyrosine kinase activity, is widely expressed on many cell types, including epithelial and mesenchymal lineages. Upon activation by at least five genetically distinct ligands (including EGF, transforming growth factor-alpha (TGF alpha) and heparin-binding EGF (HB-EGF)), the intrinsic kinase is activated and EGFR tyrosyl-phosphorylates itself and numerous intermediary effector molecules, including closely-related c-erbB receptor family members. This initiates myriad signaling pathways, some of which attenuate receptor signaling. The integrated biological responses to EGFR signaling are pleiotropic including mitogenesis or apoptosis, enhanced cell motility, protein secretion, and differentiation or dedifferentiation. In addition to being implicated in organ morphogenesis, maintenance and repair, upregulated EGFR signaling has been correlated in a wide variety of tumors with progression to invasion and metastasis. Thus, EGFR and its downstream signaling molecules' are targets for therapeutic interventions in wound repair and cancer.

New innovations in scar management.

Widgerow AD, Chait LA, Stals R, Stals PJ.

Aesthetic Plast Surg 2000 May-Jun;24(3):227-34

As current aesthetic surgical techniques become more standardized and results more predictable, a fine scar may be the demarcating line between acceptable and unacceptable aesthetic results. With this in mind, a scar management program has been adopted based on the modalities of wound support, hydration, and hastened maturity, all factors gleaned from scientific evidence published over the past 25 years. Tension on a scar in one axis will result in a stretched scar, probably initiated by neutrophils and their neutral proteases [18,26]. Tension on a scar from many directions or intermittently will result in a hypertrophic scar, possibly initiated by lymphocytes but definitely related to a prolongation of the inflammatory process, with increased fibroblast activity and overabundant extracellular matrix secretion [24,26]. The common initiating factor is the tension on the scar, and the critical element needed to counteract this tension is scar support. Clinical experience has shown us that the most reliable way to support a scar is by using microporous tape. Hydration is a second beneficial influence on scar control and is the basis of the use of silicone sheeting and gel [7,29,36]. Alpha Centella cream has two main components. The first is an extract from the plant Bulbine frutescens. This increases hydration under the tape by leaving a layer of fatty vesicles of glycoprotein on the skin surface. This also has antibacterial properties. The second component is the principal terpenoids extracted from the Centella asiatica plant. These include Asiatic acid, madecassic acid, and asiaticoside. Centella asiatica has been documented to aid wound healing in a large number of scientific reports [5,12,21,22,33,34,40]. The most beneficial effect appears to be the stimulation of maturation of the scar by the production of type I collagen [4,19] and the resulting decrease in the inflammatory reaction and myofibroblast production. Thus these components have been incorporated into the formulation of a scar management program. This publication reviews much of the available literature relating to scar management and describes the formulation and use of a scar management program based on this information.

Nutritional intake and physical activity in leg ulcer patients.

Wissing U; Unosson M; Lennernas MA; Ek AC

Department of Caring Sciences, Faculty of Health Sciences, University of Linkoping, Sweden.

J Adv Nurs (England) Mar 1997, 25 (3) p571-8

The aim of the study was to describe the nutritional intake, meal patterns, physical activity and need for help in nine women living in their own homes and being treated for venous leg ulcers. Food habits were identified by use of interviews and food diaries completed by the women during a period of seven days. The intake of energy and nutrients from 304 eating events during seven days was calculated and meal patterns were evaluated using a qualitative system for meal classification. Physical activity and the degree of need were identified with the help of interviews. The intakes of energy and key nutrients for wound healing, such as protein, vitamin C and zinc, were not optimal according to the Swedish nutrition recommendations, although food habits were well organized. Most of the women had hardly any physical activities and the need of help and support varied, from daily visits to visits every second week.

Prevalence of magnesium and zinc deficiencies in nursing home residents in Germany.

Worwag M, Classen HG, Schumacher E. Department of Pharmacology and Toxicology of Nutrition, University of Hohenheim, Stuttgart, Germany.

Magnes Res. 1999 Sep;12(3):181-9.

In a multicentric study with 345 seniors over 70 years old we investigated magnesium and zinc levels in serum together with the prevalence of their typical symptoms of deficiency in nursing home residents (NHR) and non-nursing home residents (nNHR). In addition calcium, sodium and potassium levels in serum were determined as well as creatinine and albumin. Considering all seniors 33 per cent exhibited hypomagnesemia and 19 per cent hypozincemia. Zinc levels of female and male NHR were significantly lower than levels of nNHR. Hypomagnesemia was significantly associated with calf cramps and with diabetes mellitus. Hypozincemia was significantly associated with impaired wound healing.

The contribution of vitamin C to healing of experimental fractures.

Yilmaz C, Erdemli E, Selek H, Kinik H, Arikan M, Erdemli B. Department of Orthopaedics and Traumatology, University of Ankara Medical School, Turkey. cyilmaz@doctor.com

Arch Orthop Trauma Surg 2001 Jul;121(7):426-8

The benefits of various minerals and vitamins on fracture healing have been demonstrated in animal models. Vitamin C is an essential substance in fracture healing but has not been studied previously on an experimental basis. Sixteen rats were grouped randomly into control and vitamin C-supplemented groups. The right tibias of all rats were fractured by digital manipulation. One group received single high dose of vitamin C intramuscularly. On the 5th, 10th, 15th, and 20th days, two rats from each group were killed and the tibias examined under light microscopy. It was seen that the vitamin C-supplemented group went through the stages of fracture healing faster compared with the control group.

Activation of a mouse macrophage cell line by acemannan: the major carbohydrate fraction from Aloe vera gel.

Zhang L, Tizard IR. Department of Veterinary Pathobiology, Texas A & M University College Station 77843, USA.

Immunopharmacology 1996 Nov;35(2):119-28

Acemannan is the name given to the major carbohydrate fraction obtained from the gel of the Aloe vera leaf. It has been claimed to have several important therapeutic properties including acceleration of wound healing, immune stimulation, anti-cancer and anti-viral effects. However, the biological mechanisms of these activities are unclear. Because of this wide diversity of effects, it is believed that they may be exerted through pluripotent effector cells such as macrophages. The effects of acemannan on the mouse macrophage cell line, RAW 264.7 cells were therefore investigated. It was found that acemannan could stimulate macrophage cytokine production, nitric oxide release, surface molecule expression, and cell morphologic changes. The production of the cytokines IL-6 and TNF-alpha were dependent on the dose of acemannan provided. Nitric oxide production, cell morphologic changes and surface antigen expression were increased in response to stimulation by a mixture of acemannan and IFN-gamma. These results suggest that acemannan may function, at least in part, through macrophage activation.

SUGGESTED READING

Drotrecogin alfa (recombinant human activated protein C) for the treatment of severe sepsis.

McCoy C, Matthews SJ. Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA. cmccoy@caregroup.harvard.edu

Clin Ther. 2003 Feb;25(2):396-421.

BACKGROUND: The search for a life-preserving drug to treat sepsis has increased understanding of the pathogenesis of the process but produced little in the way of successful treatments. The prospective, randomized, double-blind, placebo-controlled, Phase III, multicenter Recombinant Human Activated Protein C Worldwide Evaluation in Severe Sepsis (PROWESS) trial suggested that drotrecogin alfa--recombinant human activated protein C--significantly improved 28-day mortality rates in acute sepsis (P = 0.005).

OBJECTIVES: The goals of this drug review were to summarize the recent findings regarding the pathogenesis of sepsis and septic shock, as well as the results of select immunomodulator drug trials, and to offer a comprehensive review of the mechanism of action, pharmacokinetic profile, efficacy and safety profile, and pharmacoeconomics of drotrecogin alfa.

METHODS: The English-language literature was searched using the EMBASE and MEDLINE databases. In EMBASE, the subject headings drotrecogin, activated protein C, and sepsis were used to search publications from 1980 through September 2002. In MEDLINE, the MeSH heading protein C and subject heading sepsis were used to search publications from 1966 through September 2002. Published abstracts of recent meetings and proceedings of the US Food and Drug Administration were also reviewed.

RESULTS: Drotrecogin alfa mimics the endogenous protein depleted during acute sepsis. Its activity as an antithrombotic, anti-inflammatory, and profibrinolytic agent appears to diminish the negative outcomes of acute sepsis, notably mortality at 28 days. The results of the PROWESS trial support this finding. A bleeding risk was noted during Phase II and III trials despite efforts to exclude those patients at high risk of bleeding.

CONCLUSIONS: Drotrecogin alfa is the first adjunctive agent for the treatment of sepsis to display clinically and statistically significant effects on mortality rates at 28 days. Many questions remain regarding which patients are ideal candidates for treatment. New research and treatment guidelines are necessary to address these questions.

The use of antioxidants in healing

Martin A
Warner-Lambert Company, Morris Plains, New Jersey 07950, USA.
Dermatologic Surgery (USA), 1996, 22/2 (156-160)

BACKGROUND. Antioxidants enhance the healing of infected and noninfected wounds by reducing the damage caused by oxygen radicals.

OBJECTIVE. Studies were conducted to determine if the CRT components (vitamin E, sodium pyruvate, and specific fatty acids) could synergistically enhance healing.

METHODS. In vitro and in vivo studies were used to assess the effect of various combination of CRT components.

RESULTS. CRT reduced oxidative damage to keratinocytes and monocytes exposed to ultraviolet light and toxic chemicals and provided protection to human subjects exposed to ultraviolet irradiation. CRT dramatically facilitated healing of infected and noninfected wounds. In herpes-infected guinea pigs, CRT reduced vaginal viral lesion development, severity, and duration, thus facilitated healing of the lesions. CRT also reversed doxorubicin cytotoxicity in monocytes and reversed doxorubicin-impaired wound healing in rats.

CONCLUSION: The CRT colly to enhancing healing of injuries.

Differential regulation of macrophage arginine metabolism: a proposed role in wound healing.

Shearer JD; Richards JR; Mills CD; Caldwell MD
Department of Surgery, University of Minnesota, Minneapolis 55455, USA.
Am J Physiol (United States) Feb 1997, 272 (2 Pt 1) pE181-90

Nitric oxide (NO) and ornithine, products of NO synthase or arginase, respectively, have opposing biological activities. The effect of mediators of leukocyte activation and inhibition on arginine metabolism of resident mouse peritoneal exudate cells (MPEC) was determined. Factors that increased basal NO synthase activity, interferon (IFN)-gamma and lipopolysaccharide (LPS), decreased arginase activity in intact cells. Transforming growth factor (TGF)-beta1 decreased IFN-gamma-stimulated NO synthase activity and produced a reciprocal increase in urea and ornithine release. TGF-beta1 had no effect on the activity of these enzymes in LPS-stimulated MPEC. Corticosterone (Cort, 100 ng/ml) decreased the basal activity of both enzymes.However, Cort inhibited NO synthase activity and increased ornithine release in MPEC exposed to IFN-gamma or LPS. The difference between arginase activity in intact cells vs. that of cell lysates suggested intracellular inhibition of arginase activity. Products of NO synthase, NO and citrulline, were shown to inhibit MPEC arginase activity under maximal assay conditions. Intracellular pH was not altered by exposure of MPEC to LPS, IFN-gamma, TGF-beta, and Cort. This reciprocal change in arginine metabolism is proposed to be an important component of wound healing. Expression of NO synthase creates a cytotoxic environment that may be important to the early phase of wound healing. As wound healing progresses, increased arginase activity produces an environment favorable for fibroblast replication and collagen production.

The utilization of nutrient substances during wound healing

Mayer NA; Muller MJ; Herndon DN
Anesteziol Reanimatol (Russia) Sep-Oct 1996, (5) p29-39

The process of wound healing represents a series of complex physicochemical reactions requiring different nutritional microcomponents at each stage. In patients with extremely grave diseases and injuries the course of wound healing is impaired because of a hypermetabolic reaction to stress, leading to protein catabolism. The hypothalamus responds to cytokine stimulation by changes of thermoregulation (increase of heat production) and increased production of stress hormones (catecholamines, hydrocortisone, and glucagon). In turn, stress hormones trigsis and proteolysis processes. Hyperproduction of glucose at the expense of skeletal muscle tissue degradation leads to the formation of amino acid substrate for liver glyconeogenesis. Additional nutrients are obligatory for wound healing in such patients. Protein catabolism cannot be arrested by amino acids alone partly because amino acid transport is impaired; it can be normalized by anabolics, such as growth hormone and insulin-like growth factor 1. Treatment with growth hormone yields a dramatic positive effect in severely burned children. Proteins and vitamins, specifically arginine and vitamins A, B, and C provide the optimal nutritive support during wound treatment.

A multicenter clinical trial. Zinc acexamate versus famotidine in the treatment of acute duodenal ulcer. Study Group of Zinc acexamate (new UP doses)

Garcia-Plaza A; Arenas JI; Belda O; Diago A; Dominguez A; Fernandez C; Martin L; Pallares A; Rodrigo L; de la Santa Jw
Rev Esp Enferm Dig (Spain) Nov 1996, 88 (11) p757-62

A multicentric double-blind trial comparing 600 mg/d of Zinc Acexamate (ACZ) and 40 mg/d of Famotidine (FMT) in the short term treatment of acute duodenal ulcer included 199 patients, diagnosed by endoscopy. One-hundred and five patients received ACZ and 94 FMT, during four weeks. A clinical control took place at two weeks and a second clinical and endoscopic control at the end of the treatment (4 weeks). Complete cicatrization of the ulcer was observed in 56.5% of patients on ACZ and in 69.5% of patients of FMT (N.S.). A reduction of more than 50% of the ulcer diameter was recorded in 78.8% of the ACZ group and in 79.9% of the FMT group. Alcohol and smoking did not influence the results. Both treatments were equally effective in the disappearance of symptoms. The incidence of adverse reactions was very low in both groups (< 5%) and no patient dropped from the trial for this reason. In conclusion, a dosage of 600 mg/d of ACZ has ptors:

Endogenous zinc concentrations in cysteamine-induced duodenal ulcers in the rat.

Troskot B; Simicevic VN; Dodig M; Rotkvic I; Ivankovic D; Duvnjak M
Department of Gastroenterology, University Hospital Sestre Milosrdnice, Medical School, University of Zagreb, Croatia.
Biometals (England) Oct 1996, 9 (4) p371-5

Exogenously administered zinc compounds have been shown to possess anti-ulcer activity against a wide variety of ulcerogenic agents, both in laboratory animal models and in human peptic ulcer disease. However, a strong possibility exists that endogenous zinc may also play an important role during noxious events by various mechanisms. Therefore, the aim of this study was to focus on the changes of endogenous zinc serum and tissue concentrations in cysteamine-induced duodenal lesions. We used atomic absorption spectrophotometry to determine the tissue and serum concentrations of zinc in normal (control) rats and those with cysteamine-induced duodenal ulcers. The results obtained in this study indicated that the onset, development and spontaneous healing of ulcer lesions were associated with certain shifts in zinc serum and tissue concentrations. Prior to ulcer formation, a significant increase was noted in serum zinc values. With the onset of duodenal lesions, zinc serum concentrations significantly decreased, while there was a significant increase in duodenal tissue concentrations when compared to healthy control animals. Zinc tissue concentrations decreased and returned to starting values by the end of the first week of spontaneous healing. This decrease in zinc tissue concentration corresponded to the healing rate of the duodenal ulcers. Serum zinc concentrations also returned to starting values within the first week period. These observations indicate and confirm that zinc could play an important role in duodenal ulcer disease and represent a natural defense system in the body.

Vitamin supplementation? Experimental study on humans.

Vaxman F; Olender S; Lambert A; Nisand G; Grenier JF
INSERM U61 et Laboratoire Pautrier, Chirurgie B, Hopitaux Universitaires de Strasbourg, France.
Eur Surg Res (Switzerland) Jul-Aug 1996, 28 (4) p306-14

The improvement of the wound healing process in humans by vitamin supplements is still controversial because of the lack of a clearly demonstrated correlation with the mechanical properties of scars.

OBJECTIVE: The aim of this work was to study the effects of high doses of ascorbic acid (AA) and pantothenic acid (PA) on the wound healing process of human skin.

METHOD: Two groups of patients undergoing surgery for tattoo removal by the successive resection procedure received AA (1 or 3 g/day) and PA (0.2 or 0.9 g/day). More than 80 mechanical, biological and histological parameters were investigated in both preoperated skin and the scars.

RESULTS: The breaking energy of scars was higher in group 2, and energy and treatment were directly correlated (p = 0.006). Mg and Mn significantly rose in group 2 whereas Fe decreased in a dose-dependent manner. Intragroup comparison showed patient and treatment effects for Mg, a time.treatment effect for Cu and a treatment effect for Fe.

CONCLUSION: The degree and rapidity of variations rather than the variations of the absolute values themselves of fibroblasts, hydroxyproline, Fe, Cu and Mg are significantly related to the enhancement of the mechanical properties of scars. From this study, it may be assumed that in order to obtain 'better', more solid and resistant scars, the decrease of Fe must be quick and acute in order to avoid the harmful effects of toxic radicals; the increase of Cu, Mg and Mn must be early and high in order to have more stable and solid collagen.

Human dermal fibroblasts produce nitric oxide and express both constitutive and inducible nitric oxide synthase isoforms.

Wang R; Ghahary A; Shen YJ; Scott PG; Tredget EE
Department of Surgery, University of Alberta, Edmonton, Canada.
J Invest Dermatol (United States) Mar 1996, 106 (3) p419-27

Nitric oxide (NO) is produced by a variety of human and animal cells and is involved in a broad rray of physiological and pathophysiological processes. It can cause vasodilation, serve as a neurotransmitter, and have anti-neoplastic, anti-microbial, and anti-proliferative effects. In this study, we have demonstrated that fibroblasts derived from human skin spontaneously produce NO and that this production can be enhanced by stimulating the cells with interferon-gamma and lipopolysaccharide. The production of NO by human dermal fibroblasts can be blocked by NG-monomethyl-L-arginine (L-NMMA). The inhibitory effect of L-NMMA on NO production was restored by addition of L-arginine but not D-arginine. By measuring the rate of conversion of [14C]L-arginine to [14C]L-citrulline, we show that unstimulated cells expressed only Ca2+-dependent NO synthase (NOS) activity (1.36 +/- 0.57 pmol/mg/min; n = 4) whereas stimulated cells expressed both Ca2+-dependent (2.60 +/- 0.54 pmol/mg/min; n = 4) and -independent (1.59 +/- 0.14 pmol/mg/min; n = 4) NOS activities. With reverse transcription polymerase chain reaction (RT-PCR), the 422-bp RT-PCR product for human endothelial constitutive NOS and the 462-bp RT-PCR product for human hepatocyte inducible NOS were detected in proportion to the amount of mRNA-related RT-cDNA added to the reaction mixture. Further evidence by immunocytochemistry demonstrated that human dermal fibroblasts express both constitutive and inducible NOS proteins. These data collectively suggest that in addition to macrophages and other inflammatory cells, nitric oxide production by dermal fibroblasts could be important during the inflammatory stages of wound healing and possibly also in the later stages of proliferation and tissue remodeling after skin injury in humans.

Nutritional factors affecting wound healing

Thomas DR
Ostomy Wound Manage (United States) Jun 1996, 42 (5) p40-2, 44-6, 48-9

The consistent relationship between poor nutritional status and risk of complications forms the cornerstone of nutritional support. Yet there is controversy about the ability of nutritional support to reduce complications or improve wound healing. This controversy stems from a number of issues. Diagnosing poor nutrition is not always easy and straight forward. There is sometimes a question whether a patient is malnourished or simply in overall poor health. Studies examining the relationship between nutrition and patient outcome are typically based on animal rather than human models. Even in clinical settings, aspects of care such as enteral or parenteral nutrient delivery may decrease the benefit of nutritional support, making outcomes even harder to measure. The effect of specific nutrients have been examined, such as protein, amino acids, vitamins C and A, and zinc. However, there are still questions regarding how much individual supplementation of a nutrient will positively affect overall outcomes. Although the relationship between specific nutrients and wound healing is not clearly defined by current studies, each patient should be provided with a complete, balanced therapeutic diet. There is at least suggestive evidence that improvement in nutritional status can improve outcomes of wound healing.

Role of lactose, arginine and lysine combination in fracture healing (an experimental study)

Fini M; Giardino R; Nicoli Aldini N; Martini L; Rocca M; Bertoni F; Capelli S; Cantelli Forti G; Sapone A; Rossetti A; Morrone G; Giavaresi G
Cattedra di Fisiopatologia Chirurgica, Universita di Bologna.
Ann Ital Chir (Italy) Jan-Feb 1996, 67 (1) p77-82; discussion 82-3

L-arginine and L-lysine are essential amino acids which seem to possess some properties able to influence bone fractures healing. In fact, the increase of intestinal calcium adsorption but also in collagen synthesis, in insulin and growth hormone secretion and in osteoblastic activation. So, an experimental in vivo model was carried out by using 50 adult rabbits which, under general anaesthesia, were submitted to an osteotomy of the left fibula. Animals were divided into 5 groups and were daily treated with a mixture of lactose, L-arginine and L-lysine or with the only lactose (control group) at the same dosage as recommended for humans. They were sacrificed after 15, 30, 40, 50 and 60 days for radiological and histological studies. The results of the study showed that the pharmacological mixture containing L-arginine and L-lysine accelerates and ameliorates the healing processes and this positive effect was particularly evident from the 30th day after the osteotomy. We think that these results are linked not only to calcium metabolism but also to different biological properties which positively contribute to good healing of bone fractures.

Activation of a mouse macrophage cell line by acemannan: The major carbohydrate fraction from Aloe vera gel

Zhang L.; Tizard I.R.
Dept. of Veterinary Pathobiology, Texas A and M University, College Station, TX 77843 USA
Immunopharmacology (Netherlands), 1996, 35/2 (119-128)

Acemannan is the name given to the major carbohydrate fraction obtained from the gel of the Aloe vera leaf. It has been claimed to have several important therapeutic properties including acceleration of wound healing, immune stimulation, anti-cancer and anti-viral effects. However, the biological mechanisms of these activities are unclear. Because of this wide diversity of effects, it is believed that they may be exerted through pluripotent effector cells such as macrophages. The effects of acemannan on the mouse macrophage cell line, RAW 264.7 cells were therefore investigated. It was found that acemannan could stimulate macrophage cytokine production, nitric oxide release, surface molecule expression, and cell morphologic changes. The production of the cytokines IL-6 and TNF-alpha were dependent on the dose of acemannan provided. Nitric oxide production, cell morphologic changes and surface antigen expression were increased in response to stimulation by a mixture of acemannan and IFN-gamma. These results suggest that acemannan may function, at least in part, through macrophage activation.

Wound healing effects of aloe gel and other topical antibacterial agents on rat skin

Heggers J.P.; Kucukcelebi A.; Stabenau C.J.; Ko F.; Broemeling L.D.; Robson M.C.
Dept Surg Plastic/Microbiol/Immunol., Univ. Texas Medical Branch/Shriners, Burns Institute, Galveston, TX 77550 USA
Phytotherapy Research (United Kingdom), 1995, 9/6 (455-457YRE)

The effects of topical antibacterials were studied in an acute wound healing model. Sprague- Dawley rats after appropriate anaesthesia received four 1.5 cm2 dorsal defects through the skin and panniculus carnosus. Skin defects were treated for 14 days with 2% mupirocin ointment, 1% clindamycin cream, 1% silver sulfadiazine cream+Aloe vera gel, and silver sulfadiazine combined with Aloe gel. An untreated group served as controls. Each group was comprised of 10 animals each to achieve statistical significance. Wound closure rate was assessed by serial planimetry. Following healing, the breaking strength of each resultant scar was determined. Wound half-lives and overall healing rates were calculated by regressing the log of the areas of all wounds over time. Overall healing rates of all the treated groups were significantly different compared with control group (p<0.05) The Aloe group had the shortest half-life and healed faster than the control group. All the other treated groups had no longer half-lives when compared with the control group. While silver sulfadiazine+Aloe increased the breaking strength of the healed wound, Aloe alone did not, but demonstrated an increase over the control. Topical Aloe significantly enhances the rate of wound healing and when combined with silver sulfadiazine reverses the wound retardant effect observed with silver sulfadiazine. Clindamycin and mupirocin significantly delay wound closure. However mupirocin enhanced the breaking strength of the wound.

Acemannan-containing wound dressing gel reduces radiation-induced skin reactions in C3H mice

Roberts D.B.; Travis E.L.
Texas Univ. M. D. Anderson Can. Ctr., Box 66, 1515 Holcombe Blvd., Houston, TX 77030-4095 USA
International Journal of Radiation Oncology Biology Physics (USA), 1995, 32/4 (1047-1052)

Purpose: To determine (a) whether a wound dressing gel that contains acemannan extracted from aloe leaves affects the severity of radiation- induced acute skin reactions in C3H mice; (b) if so, whether other commercially available gels such as a personal lubricating jelly and a healing ointment have similar effects; and (c) when the wound dressing gel should be applied for maximum effect.

Methods and Materials: Male C3H mice received graded single doses of gamma radiation ranging from 30 to 47.5 Gy to the right leg. In most experiments, the gel was applied daily beginning immediately after irradiation. To determine timing of application for best effect, gel was applied beginning on day -7, 0, or +7 relative to the day of irradiation (day 0) and continuing for 1, 2, 3, 4, or 5 weeks. The right inner thigh of each mouse was scored on a scale of 0 to 3.5 for severity of radiation reaction from the seventh to the 35th day after irradiation. Dose- response curves were obtained by plotting the percentage of mice that reached or exceeded a given peak skin reaction as a function of dose. Curves were fitted by logit analysis and ED50 values, and 95% confidence limits were obtained.

Results: The average peak skin reactions of the wound dressing gel- treated mice were lower than those of the untreated mice at all radiation doses tested. The ED50 values for skin reactions of 2.0-2.75 were approximately 7 Gy higher in the wound dressing gel-treated mice. The average peak skin reactions and the ED50 values for mice treated with personal lubricating jelly or healing ointment were similar to irradiated control values. Reduction in the percentage of mice with skin reactions of 2.5 or more was greatest in the groups that received wound dressing gel for at least 2 weeks beginning immediately after irradiation. There was no effect if gel was applied only before irradiation or beginning 1 week after irradiation.

Conclusion: Wound dressing gel, but not personal lubricating jelly or healing ointment, reduces acute radiation-induced skin reactions in C3H mice if applied daily for at least 2 weeks beginning immediately after irradiation.

Anti-inflammatory and wound healing properties of Aloe vera

Udupa S.L.; Udupa A.L.; Kulkarni D.R.
Department of Biochemistry, Kasturba Medical College, 576119 Manipal, Karnataka India
Fitoterapia (Italy), 1994, 65/2 (141-145)

The fresh juice of the indigenous drug A. vera (0.2 ml/100 g, i.p.)was studied for its anti inflammatory and by observing percent reduction in carrageenin-induced paw oedema at 3 h. Wound healing effects were studied on incision (skin breaking strength), excision (percent wound contraction and epithelisation time) and dead space (granuloma breaking strength and biochemical parameters) wound models. A. vera showed significant anti-inflammatory activity in acute inflammatory model without any significant effect on chronic inflammation. Significant increase in breaking strength (skin and granuloma tissue), enhanced wound contraction and decreased epithelisation period were observed. An increase in lysyl oxidase activity and mucopolysaccharide content were also seen. This drug could therefore increase tensile strength by increasing cross-linking in collagen and interactions with the ground substance.

Beneficial effects of Aloe in wound healing

Heggers J.P.; Pelley R.P.; Robson M.C.
Department of Surgery, University of Texas Medical Branch, Galveston, TX 77550 USA
Phytother. Res. (United Kingdom), 1993, 7/Spec. Iss. (S48-S52)

The therapeutic effects of Aloe vera have been examined in preventing progressive dermal ischaemia caused by burns, frostbite, electrical injury,distal dying flap and intra-arterial drug abuse. In vivo analysis of these injuries showed that the mediator of progressive tissue damage was thromboxane A2 (TxA2). Experimentally Aloe was compared to a variety of antithromboxane agents to include U38450, a lodoxamide, a lazaroid and Carrington wound gel. In the burn injury Aloe when compared with the control and the Carrington wound gel (p = 0.05). Tissue survival in the experimental frostbite injury was 28.2% when compared with the control (p = 0.05). Similar results were obtained for the electrical injury, and intra-arterial drug abuse. Clinically burn patients treated with Aloe healed without tissue loss as did those with frostbite (p = 0.001). In the intra-arterial drug abuse patients Aloe reversed the tissue necrosis. This therapeutic approach was used to prevent progressive tissue loss in each injury by actively inhibiting the localized production of TxA2. Aloe not only acts as a TxA2 inhibitor but maintains a homeostasis within the vascular endothelium as well as the surrounding tissue.

The stimulation of postdermabrasion wound healing with stabilized aloe vera gel-polyethylene oxide dressing

Fulton J.E. Jr.
The Acne Research Institute, 1587 Monrovia Street, Newport Beach, CA 92663 USA
J. Dermatol. Surg. Oncol. (USA), 1990, 16/5 (460-467)

Full-face dermabrasion provided an ideal opportunity to document the effects of dressings on wound healing management. Following the procedure, the abraded face was divided in half. One side was treated with the standard polyethylene oxide gel wound dressings. The other side was treated with a polyethylene oxide gel dressing saturated with stabilized aloe vera. The polyethylene oxide dressing provided an excellent matrix for the release of aloe vera gel during the initial 5 days of wound healing. By 24-48 hours there was dramatic vasoconstriction and accompanying reduction in edema on the aloe-treated side. By the third to fourth day there was less exudate and crusting at the aloe site, and by the fifth to sixth day the reepithelialization at the aloe site was complete. Overall, wound healing was approximately 72 hours faster at the aloe site. This acceleration in wound healing is important to reduce bacterial contamination, subsequent keloid formation, and/or pigmentary changes. The exact mechanism of acceleration of wound healing by aloe vera is unknown.

Aloe vera gel hindered wound healing of experimental second-degree burns: A quantitative controlled study

Kaufman T.; Kalderon N.; Ullmann Y.; Berger J.
Department of Plastic Surgery, Bruce G. MacMillan Burn Wound Healing Research Unit, Haifa Israel
J. Burn Care Rehabil. (USA), 1988, 9/2 (156-159)

In the present study, Aloe vera gel (AVG) was applied to experimental second-degree burns in guinea pigs, and its effects on epithelialization, wound contraction, newly formed granulation tissue, and regeneration of hair follicles was compared with that effected by 1% silver sulfadiazine cream (AgSD). Epithelialization (% mean plus or minus SEM) on postburn day 8, 16, and 24 of the AVG-treated wounds was 38.72% plus or minus 2.71%, 60.34% plus or minus 3.28%, and 92.46% plus or minus 2.26%, respectively, while that of AgSD-treated burns was 53.35% plus or minus 2.65%, 94.84% plus or minus2.65%wounds was significantly higher than that of the AgSD-tr eated burns during 24 days of the study (P < .001). The thickness of the newly formed granulation tissue was higher in the AVG-treated wounds (P < .001), while the hair follicles count was significantly lower (P < .001) compared with the AgSD-treated burns. It is concluded that this preparation of Aloe vera gel hindered the healing process of the present burn wound model when compared with 1% silver sulfadiazine cream.

Biological activity of Aloe vera

Davis R.H.; Leitner M.G.; Russo J.M.; Maro N.P.
Pennsylvania College of Podiatric Medicine, Department of Physiological Sciences, Philadelphia, PA 19107 USA
Med. Sci. Res. (UK), 1987, 15/5 (235)

In this study, the authors attempted to show the comparative biological activity of Aloe vera as measured by standard anti-inflammatory tests. Wound healing was improved 24% in mice by a 100 mg/kg Aloe vera dose whereas 10 mg/kg improved healing 31% in rats. A slightly greater response of 44% was obtained on inhibiting mustard induced edema by 10 mg/kg Aloe vera. A marked inhibition of 58% PMN infiltration into an inflamed area by 2 mg/kg aloe was noted. No reduction of granuloma tissue formation around a cotton pellet under the skin was shown at doses up to 400 mg/kg. These data suggest that Aloe vera inhibits inflammation and improves wound healing. Aloe vera probably does not act like a steroid since it was most effective on acute inflammation and had no effect on granuloma tissue formation.

Cutaneous tissue repair: Practical implications of current knowledge. II

Reed B.R.; Clark R.A.F.
Department of Dermatology, University of Colorado Health Sciences Center, Denver, CO 80262 USA
J. Am. Acad. Dermatol. (USA), 1985, 13/6 (919-941)

This article reviews the scientific basis for the certain factors that delay wound repair in the clinical setting. A brief history of wound healing is given, followed by a discussion of endogenous local factors (bacterial infection, hypoxia, foreign body, and desiccation) and endogenous systemic factors (nutritional deficiencies, aging, coagulation disorders, and the Ehlers-Danlos syndromes) associated with poor wound repair. Also reviewed are the mechanisms by which exogenously administered agents (glucocorticoids, antineoplastic agents, and anticoagulants) may delay healing. Commonly used topical antimicrobials, their spectrum of activity, and evidence of effects on wound healing are examined. Finally, properties of commercially available wound coverings and wound care in the future are discussed.

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Aloe vera (gel) cream as a topical treatment for outpatient burns

Heck E.; Head M.; Nowak D.; et al.
Dept. Surg., Univ. Texas Hlth Sci. Cent., Dallas, Tex. USA
Burns (England), 1981, 7/4 (291-294)

The objectives in the use of topical agents in burn therapy are bacterial control and relief of pain. In this study a commonly discussed 'home remedy' now commercially available is compared with a widely used prescription agent in the control of bacterial flora in outpatient burn wounds. Additionally, the study examines healing times in the two groups for any demonstrated effect.

Necrolytic migratory erythema and zinc deficiency

Sinclair S. A.; Reynolds N.J.
N.J. Reynolds, Department of Dermatology, Royal Victoria Infirmacy, Queen Victoria Road, Newcastle upon Tyne NE1 4LP United Kingdom
British Journal of Dermatology (United Kingdom), 1997, 136/5 (783-785)

Necrolytic migratory erythema (NME) is an uncommon condition classically associated with high plasma levels of circulating glucagon and a glucagonoma. We report a patient with cirrhosis who showed clinical and histological features of NME. Investigation revealed normal glucagon levels without evidence of glc supplementation resulted in rapid and complete resolution of the eruption.

Sepsis impairs anastomotic collagen gene expression and synthesis: A possible role for nitric oxide

Thornton F.J.; Ahrendt G.M.; Schaffer M.R.; Tantry U.S.; Barbul A.
Dr. A. Barbul, Department of Surgery, Sinai Hospital of Baltimore, 2401 W. Belvedere Ave., Baltimore, MD 21215 USA
Journal of Surgical Research (USA), 1997, 69/1 (81-86)

Although intra-abdominal sepsis is known to impair colon healing by inhibiting anastomotic collagen synthesis, the effect of systemic sepsis on this process is unknown. Endotoxins and cytokines associated with sepsis induce nitric oxide synthesis both systemically and locally within colonic tissue. We hypothesized that systemic sepsis impairs colonic healing and examined a possible correlation with nitric oxide expression. Male Sprague- Dawley rats received intraperitoneal injections of either saline (sham group) or Escherichia coli endotoxin (lipopolysaccharide 1 mg/100 g body weight) at Times - 24 and - 12 hr (LPS group). All animals underwent laparotomy and left colonic anastomosis at Time 0. At 24 and 96 hr postlaparotomy rats were sacrificed, the anastomoses excised, and (3H)-proline incorporation into protein measured as an index of total new protein synthesis (TNP). Digestion with purified collagenase yielded incorporation into the collagen fraction (CDP). Additional sham and LPS-treated rats were sacrificed at 24, 72, and 120 hr, the anastomoses excised, and nitric oxide synthase activity in the tissue measured by the conversion of (3H)-arginine to (3H)citrulline in an ex vivo culture system. Finally, sham and LPS rats were sacrificed at 120 hr for measurement of colon anastomotic bursting pressure. Systemic sepsis significantly impaired new collagen synthesis in anamotic tissue at 24 hr compared to control samples (P < 0.02). No difference was noted at 96 hr. TNP synthesis was similar in both groups at 24 or 96 hr. Northern blot analysis confirmed a significant decrease in Type I and Type III collagen mRNA expression at 24 hr in septic rats. Anastomotic bursting pressure was also decreased in the septic group (P < 0.003). Sepsis elevated nitric oxide synthase activity in anastomotic tissue 24 hr postanastomosis, when compared to sham tissue (P < 0.0001). These data suggest that systemic endotoxin induces nitric oxide synthesis at the anastomotic site. The simultaneous dysregulation of collagen gene expression and synthesis with decreased anastomotic strength suggests a possible regulatory role for nitric oxide in gastrointestinal healing.

Regionally different vascular response to vasoactive substances in the remodelled infarcted rat heart; Aberrant vasculature in the infarct scar

Kalkman E.A.J.; Van Haren P.; Saxena P.R.; Schoemaker R.G.
R.G. Schoemaker, Department of Pharmacology, Faculty Medicine and Health Sciences, Erasmus University Rotterdam, PO Box 1738, 3000 DR Rotterdam Netherlands
Journal of Molecular and Cellular Cardiology (United Kingdom), 1997, 29/5 (1487-1497)

Remodelling after myocardial infarction (MI) is associated with vascular adaption, increasing vascular capacity of non-infarcted myocardium, and angiogenesis in the infarcted part during wound healing and scarring. We investigated regional vascular reactivity in the infarcted rat heart. Transmural infarction of the left ventricular free wall was induced by coronary artery ligation. After 3 weeks, regional flow during maximal vasodilation (nitroprusside, NPR) and submaximal vasoconstriction (arginine-vasopressin, AVP) were studied in buffer-perfused hearts. The main findings were

(1) a reduced vasodilator response (NPR) in the viable part of the left ventricular free wall, where hypertrophy was most pronounced, resulting in reduced maximal tissue perfusion of the myocardium bordering the scar (19.7 plus or minus 0.6 v 25.7 plus or minus 1.2 ml/min.g), whereas peted regions was preserved.

(2) A 54% lower vasodilator response (NPR) and a 25% stronger vasoconstriction (AVP) in scar tissue compared to viable parts of MI hearts. Microscopy showed thicker walls of resistance arteries in scar tissue than in viable parts of MI hearts or in sham hearts, morphometrically substantiated by two- to three-fold greater wall/lumen ratios. These data indicate a deviant response of scar vessels of MI hearts, and in the non-infarcted part, a reduced coronary reserve in the most hypertrophied region. Whereas the former may be caused by different vessel structure, the reduced vasodilator reserve of the spared part of the left ventricular free wall may indicate vasodilation at rest due to insufficient vascular growth. Thus, the most hypertrophied region would be at the highest risk of further ischemic damage.

Wound healing: The role of the mast cell as a zinc carrier

Hardjowasito W.; Basuki A.
Dr. W. Hardjowasito, Department of Surgery, Saiful Anwar General Hospital, Medical Faculty Brawijaya University, Jln JA Suprapto 2, Malang 65111 Indonesia
Asian Journal of Surgery (Hongkong), 1997, 20/1 (42-46)

The role of mast cells in wound healing in a racial group of Proto Malay people living in Timor, Indonesia was studied. The relationship between fine scar formation after cleft lip reconstruction surgery, the growing evidence of micronutrient zinc deficiency in the region and an unusual number of mast cells distributed in the skin compared with a racial group of Deutero Malay people living in Malang, East Java, Indonesia was explored. It has been suggested that a possible role of mast cells, in a zinc deficient area, is that they accumulate zinc to compensate for the deficiency and to provide the necessary amount for better wound healing. Further investigations are still under way to give a more sound understanding of mast cells as zinc carriers.

Modulation of tendon healing by nitric oxide

Murrell G.A.C.; Szabo C.; Hannafin J.A.; Jang D.; Dolan M.M.; Deng X.-H.; Murrell D.F.; Warren R.F.
Australia
Inflammation Research (Switzerland), 1997, 46/1 (19-27)

Nitric oxide (NO.) is a small, diffusible free radical that is generated from L-arginine by a family of enzymes, collectively termed the nitric oxide synthases. We investigated the role of NO. in tendon healing. NO. synthase activity and immunoreactivity was absent in un-injured rat Achilles tendon. After surgical division there was a five-fold increase in NO. synthase activity and immunoreactivity within the healing tendon at day 7, with a return to near baseline levels at day 14. Inhibition of NO. synthase activity with oral administration of Nomega-nitro-L-arginine methyl ester (L-NAME) resulted in a significant reduction in cross-sectional area (30% at day 7, p < 0.01, 50% at day 15, p < 0.001) and failure load (24% at day 7, p < 0.01) of the healing Achilles tendon constructs. Rats fed the same regimen of the enantiomer of L-NAME, (D-NAME) had normal tendon healing. These results indicate that nitric oxide synthase is induced during tendon healing and inhibition of nitric oxide synthase inhibits this tendon healing.

Acute protein-calorie malnutrition impairs wound healing: A possible role of decreased wound nitric oxide synthesis

Schaffer M.R.; Tantry U.; Ahrendt G.M.; Wasserkrug H.L.; Barbul A.
USA
Journal of the American College of Surgeons (USA), 1997, 184/1 (37-43)

BACKGROUND: Nitric oxide is synthesized in wounds. Systemic inhibition of wound nitric oxide synthesis decreases wound collagen accumulation and wound mechanical strength. The role of nitric oxide during impaired healing is not known. In a model of impaired wound healing induced by acute protein- calorie malnutrition, we correlated wound healing parameters with wound nitric oxide synthesis.

STUDY DESIGN: One group of Sprague-Dawley rats was rendered acutely malnourished by restricting its food intake to 50 percent of the food intake of an ad libitum-fed control group. Wound collagen accumulation and types I and III collagen gene expression were measured 10 days postwounding in subcutaneously implanted polyvinyl alcohol sponges. Nitric oxide synthesis was determined in wound fluid and in supernatants of wound cell cultures.

RESULTS: Animals with acute protein-calorie malnutrition lost 10.4plus or minus0.8 percent, while controls gained 17.5plus or minus1.2 percent of their original body weight. Protein-calorie malnutrition reduced sponge hydroxyproline contents (995plus or minus84 compare with 1,580plus or minus109 microg/100 mg sponge, p<.001), indicating diminished wound collagen accumulation. Gene expression of type III, but not type I, collagen was decreased in wounds of protein- calorie malnutrition animals. Nitrite/nitrate and citrulline concentrations in wound fluid (p<.01) and in wound cell supernatants (p<.001) were also lower in protein-calorie malnutrition animals, indicating a net decrease in nitric oxide production.

CONCLUSIONS: Impaired wound collagen accumulation caused by protein-calorie malnutrition may be a reflection of reduced nitric oxide synthesis within the wound.

Interaction between the insulin-like growth factor family and the integrin receptor family in tissue repair processes: Evidence in a rabbit

Galiano R.D.; Zhao L.L.; Clemmons D.R.; Roth S.I.; Lin X.; Mustoe T.A.
USA
Journal of Clinical Investigation (USA), 1996, 98/11 (2462-2468)

We have determined previously that IGF-I is dependent on the presence of IGF binding protein-1 (IGFBP-1) to act as a wound healing agent. We sought to determine the mechanism whereby IGFBP-1 is able to enhance IGF-I bioactivity. As IGFBP-1 binds both the alphleft arrow over right arrowbeta1 integrin as well as IGF-I in vitro, we asked which of the following interactions were important: (a) the ability of IGFBP- 1 to interact with an integrin receptor, and/or (b) the binding of IGF-I by IGFBP-1. We used an IGF-1 analogue (des(1-3)IGF-I) with a > 100-fold reduction in affinity for IGFBP-1 as well as an IGFBP-1 mutant (WGD-IGFBP-1) which does not associate with the alphleft arrow over right arrowbeta1 integrin to selectively abrogate each of these interactions. We also tested the ability of IGFBP-2, a related bies not associate with integrin family members, to enhance IGF-I bioactivity. Full- thickness dermal wounds were created on rabbit ears; various combinations of native IGF-I, native IGFBP-1, native IGFBP-2, and their respective analogues/mutants were applied to each wound. Wounds were harvested 7 d later for analysis. Only native IGF-I in combination with native IGFBP-1 was effective as a wound healing agent, enhancing reepithelialization and granulation tissue deposition by 64plus or minus5 and 83plus or minus12% over controls (P = 0.008 and 0.016, respectively). The same doses of IGF-I/WGD-IGFBP-1, des(1-3)IGF- I/IGFBP-1, and IGF-I/IGFBP-2 were ineffective. We propose that IGF-I physically interacts with IGFBP-1 and that IGFBP-1 also binds to an integrin receptor, most likely the alphleft arrow over right arrowbeta1 integrin. This interaction is unique to IGFBP-1 as the closely related IGFBP-2 had no effect, a finding consistent with its inability to bind to integrin receptors. Our results suggest that activation of both the IGF-I receptor and the alphleft arrow over right arrowbeta1 integrin is required for IGF-I to stimulate wound healing.

Dietary L-arginine in renal disease

Peters H.; Noble N.A.
Division of Nephrology, Univ. of Utah School of Medicine, Salt lake City, UT 84132 USA
Seminars in Nephrology (USA), 1996, 16/6 (567-575)

The amino acid L-arginine is a substrate for at least three products involved extensively in tissue injury and fibrosis. L-arginine is metabolized to L-proline, a major constituent of the collagen that makes up fibrotic extracellular matrix. L-arginine is a precursor for polyamines, which are required for proliferative responses characteristic of many renal diseases. L-arginine is also the sole substrate for generation of nitric oxide (NO) which, produced in large quantities by macrophages, has been implicated in tissue injury. On the other hand, NO produced in small quantities endothelium is a critical vasodilator. Given the importance of elevated intraglomerular pressure in renal injury, it is perhaps not surprising that dietary L-arginine supplementation increases NO generation and is beneficial in reducing intraglomerular pressure and subsequent disease. Other data, based on the therapeutic effects of low protein diets, have suggested that L- arginine restriction limits NO-mediated glomerular injury and greatly reduces matrix accumulation, consistent with the idea that limitation of substrate effectively diminishes injurious NO levels, polyamine synthesis, and collagen production.

Serum protein and zinc levels in patients with thoracic empyema

Balkan M.E.; Ozgunes H.
Department of Thoracic Surgery, Ataturk Chest Dis./Surgical Ctr., 8 06280 Kecioren, Ankara Turkey
Biological Trace Element Research (USA), 1996, 54/2 (105-112)

The element Zn is the metal component or activator of many important enzymes. The tissue concentrations and activities of Zn metalloenzymes direct the rate of protein and nucleic acid syntheses, thereby influencing tissue growth and reparative processes. Most of the serum Zn is normally bound to circulating proteins. Low serum Zn concentrations might result from depletion of Zn-binding proteins. Serum protein and Zn concentrations have been reported to be depressed in patients with acute and chronic diseases. We compare the serum protein and Zn values of patients with thoracic empyema (n = 20) with those of a control group (n = 20). The values obtained in the empyema group were significantly lower than those in the control group before the study. Test group administered 220 mg zinc sulfate (ZnSO4. 7H2O) over 20 d and there was a significant increase in the values for serum protein and Zn after the oral administration of the zinc sulfate.

Arginine-enriched diets: Rationale for use and experimental data

Cynober L.; Vasson M.-P.; Aussel C.
Laboratoire de Biochimie, Biologie Moleculaire et Nutrition, UFR de Pharmacie, 28, place Henri-Dunant, 63001 Clermont-Ferrand Cedex 1 France
Nutrition Clinique et Metabolisme (France), 1996, 10/2 (89-95)

Since the pioneering work of Rose who classified arginine as a non- essential amino acid, subsequent works have revealed that arginine can become an essential amino acid in stress situations. In septic rats, arginine- enriched nutrition (either enteral or parenteral) improves nitrogen balance and total body and liver protein synthesis. In addition, arginine stimulates growth hormone and insulin secretion. The most remarkable action of arginine is certainly that exerted on cellular immunity. This action concerns thymus and extra-thymus areas. Finally, arginine favours wound healing improves host defenses in cancer and slows tumour growth. The pharmacological action of arginine probably depends upon various mechanisms: its action on immunity may be mediated by the synthesis of nitric oxide and polyamines (via ornithine synthesis). The effect on wound healing may be related to proline synthesis. The effects on nitrogen metabolism may be linked to growth hormone secretion. These observations form the rationale for the administration of arginine- enriched diets to injured patients.

Protection by zinc against UVA- and UVB-induced cellular and genomic damage in vivo and in vitro

Record I.R.; Jannes M.; Dreosti I.E.
CSIRO Division of Human Nutrition, Gouger St, Adelaide, SA 5000 Australia
Biological Trace Element Research (USA), 1996, 53/1-3 (19-25)

For many years, zinc salts have been used both topically and orally to treat minor burns and abrasions as well as to enhance wound repair in man and animals. In this study we describe the protective effects of zinc against UV- induced genotoxicity in vitro and against sunburn cell formation in mouse skin in vivo. Cultured skin cells from neonatal mice showed a dramatic increase in the number of micronuclei as a result of UVA and UVB irradiation. Inclusion of zinc at 5 microg/mL in the medium significantly reduced the frequency of micronuclei and of micronucleated cells. In hairless mice, topical application of zinc chloride for 5 consecutive days or a single application 2 h prior to UV exposure reduced the number of sunburn cells in the epidermis as did application of zinc 1 h after exposure. Application 2 h after irradiation also tended to have a protective effect, although there was a large variation between animals. It is proposed that an influx of zinc can protect epidermal cells against some of the more delayed effects of UV-induced damage.

Nutrition and wound healing

Collins C.M.
Care of the Critically Ill (United Kingdom), 1996, 12/3 (87-90)

Nutrition is an important factor in the outcome of clinical conditions, including injury. Although many micronutrients are essential factors in the healing process, there is little clinical proof that deficiency states delay wound healing. However, global nutrition support has been demonstrated to reduce the development of non-wound complications that indirectly prolong wound healing. Specific nutrients may have additional immunomodulatory influences that positively affect wound healing.

Effect of the hydroxyl radical on fibroblast-mediated collagen remodelling in vitro

Arisawa S.; Arisawa T.; Ohashi M.; Nitta Y.; Ikeya T.; Asai J.
Second Dept. of Internal Medicine, Nagoya University School of Medicine, Tsurumacho, Nagoya 466 Japan
Clinical and Experimental Pharmacology and Physiology (Australia), 1996, 23/3 (222-228)

It has been reported that free radicals prevent wound healing. However, the mechanism of this effect is not yet clear. We attempted to clarify the influence of hydroxyl radicals on wound healing in vitro. We used an ascorbate-copper ion system (ACS) to produce hydroxyl radicals in accordance with variables of time elapsed and concentration of copper ion. The effects of hydroxyl radical on fibroblast-mediated collagen remodelling, cell viability, the functions of fibroblasts and collagen fibrils were studied. With a copper ion concentration of 100 micromol/L ACS significantly reduced contraction, while 10 micromol/L stimulated contraction. Hydrogen peroxide (H2O2) was employed in observing these findings. ACS did not influence cell viability, the expression of alpha2beta1 integrin and cellular fibronectin, or the cytoskeletal organization of fibroblasts involving actin until 3 h. A concentration of ACS at 10 micromol/L of copper ion induced the polymerization of collagen after 30 min, while ACS at 100 micromol/L induced collagen degradation, this finding was also established by using H2O2. Collagen reduced the amount of formaldehyde produced by trapping hydroxyl radical with dimethyl sulfoxide. Our findings suggest that collagen is denatured by scavenging the hydroxyl radical before fibroblasts are damaged, so that the radical may influence the remodelling of collagen.

Prevention of the inhibitory effect of intraperitoneal 5-FU on intestinal anastomosis by zinc

Tumer A.R.; Kama N.A.; Muftuoglu S.F.; Dener C.; Tumer L.; Dagdeviren A.
4 Cerrahi Servisi, Ankara Numune Hastanesi, Ankara Turkey
Turkish Journal of Gastroenterology (Turkey), 1996, 7/1 (72-81)

Today adjuvant therapy using early postoperative intraperitoneal chemotherapy, is particularly appropriate treatment to prevent the local and regional recurrence in resectable colon cancers. Intraperitoneal 5-Fluorouracil (5-FU) is the most preferable agent for this purpose. The aim of this study is to determine the effect of Zn against the inhibitory effect of 5-FU on the healing of colonic anastomosis. In 5-FU treated group, average bursting pressure (p:0.048) and hydroxyproline levels were significantly decreased (p:0.015). In only Zn treated group, average bursting pressure was significantly increased (p:0.02) whereas hydroxyproline levels showed no correlation with the control group (p:0.560). In both 5-FU and Zn treated groups average bursting pressure had statistically significant correlation only with the 5-FU treated group (p:0.014). In this group hydroxyproline levels were increased as well (p:0.014). The histological observations showed that 5-FU impaired the healing of colonic anastomosis with the appearance of necrotic tissue at the anastomosis region. However the 5-FU and Zn groups appeared to be nearly completely epithelialized and also the number of fibroblasts were increased while necrotic ti much as in the 5-FU treated group. We conclude that Zn addition modulates healing of colonic anastomosis by counteracting the negative effect of 5-FU.

Nutritional pharmacology and malignant disease: A therapeutic modality in patients with cancer

Heys S.D.; Gough D.B.; Khan L.; Eremin O.
Surgical Nutrition/Metabolism Unit, University of Aberdeen, Medical School Buildings, Foresterhill, Aberdeen AB9 2ZD United Kingdom
British Journal of Surgery (United Kingdom), 1996, 83/5 (608-619)

It is now established that certain nutrients have a significant effect on cellular metabolism and growth, tissue repair and regeneration, and modulation of host defences. So far, however, potential clinical benefits have been difficult to demonstrate. Nevertheless, the use of nutrients in combinations seems to have promise and may be associated with a reduction in infectious complications and length of hospital stay. Nutritional pharmacology in the future may be able to improve tumour response to chemotherapy and may minimize the metabolic effect of cachexia.

Essential microminerals and their response to burn injury

Gamliel Z.; DeBiasse M.A.; Demling R.H.
Journal of Burn Care and Rehabilitation (USA), 1996, 17/3 (264-272)

Certain microminerals, named because of their minute quantities in the body, are essential components for maintaining homeostasis involving, in particular, metabolism, immune defenses, and wound healing. In general, these trace elements are characterized by having multiple roles and by demonstrating deficiency syndromes that are complex and difficult to diagnosis. The response of the microminerals to injury, especially burn injury, is not well defined. The purpose of this article is to describe the known roles of the trace elements and the effect of burn injury on circulating and tissue levels. As will be noted, much less is known regarding the impact of trace elements' changes on the injury process than the role of these elements in the normal state. In addition, the amount of trace elements needed for the stress changes after injury are, for the most part, undefined.

Effects of an arginine-glycine-aspartic acid peptide-containing artificial matrix on epithelial migration in vitro and experimental second-degree burn wound healing in vivo

Mertz P.M.; Davis S.C.; Franzen L.; Uchima F.-D.; Pickett M.P.; Pierschbacher M.D.; Polarek J.W.
Dermatology/Cutaneous Surgery Dept., University of Miami Sch. of Medicine, 1600 NW 10th St., Miami, FL 33136 USA
Journal of Burn Care and Rehabilitation (USA), 1996, 17/3 (199-206)

Cells central to dermal tissue repair such as dermal fibroblasts and keratinocytes interact with arginine-glycine-aspartic acid (RGD)-containing proteins of the extracellular matrix such as fibronectin. It has been shown that synthetic peptides containing this RGD sequence can also support cell attachment and migration in vitro. We therefore set out to test whether the use of these peptides, when formulated as a synthetic RGD-peptide matrix consisting of peptide complexed with hyaluronic acid, would have an effect on the rate of epithelial migration and hounds. Evaluation consisted of measuring the extent of epithelial outgrowth from human dermal explants and the epithelization of experimental second-degree burn wounds in pigs. We show here that the RGD-peptide matrix supports epithelial sheet migration from explants in a dose-dependent manner. In second-degree burn wounds in pigs, wounds treated with daily applications of the RGD peptide matrix under occlusion resurfaced at a significantly faster rate (day 7 = 57% completely epithelized) than wounds treated with hyaluronic acid under occlusion (day 7 = 13% completely epithelized, p < 0.01), occlusion alone (day 7 = 13% completely epithelized, p < 0.01), or air exposed (day 7 = 0% completely epithelized, p < 0.001). Histologic examination showed that wounds treated with the RGD-peptide matrix also had thicker epithelial covering and greater granulation tissue deposition than occluded, air-exposed, and hyaluronate-treated wounds. These data therefore show that the use of RGD-peptide matrix induces faster explant epithelial migration and results in faster healing of experimental second-degree burns.

Spontaneously increased production of nitric oxide and aberrant expression of the inducible nitric oxide synthase in vivo in the transforming growth factor beta1 null mouse

Vodovotz Y.; Geiser A.G.; Chesler L.; Letterio J.J.; Campbell A.; Lucia M.S.; Sporn M.B.; Roberts A.B.
Laboratory of Chemoprevention, National Institutes of Health, Building 41, Bethesda, MD 20892 USA
Journal of Experimental Medicine (USA), 1996, 183/5 (2337-2342)

Transforming growth factor beta1 null mice (TGF-beta1(-/-)) suffer from multifocal inflammation and die by 3-4 wk of age. In these mice, levels of nitric oxide (NO) reaction products in serum are elevated approximately fourfold over levels m controls, peaking at 15-17 d of life. Short-term treatment of TGF-beta1(-/-) mice with N(G)-monomethyl-L-arginine suppressed this elevated production of NO. Expression of inducible NO synthase (iNOS) mRNA and protein is increased in the kidney and heart of TGF-beta1(-/-) mice. These findings demonstrate that TGF-betaerred from mechanistic studies o n the control of iNOS expression by TGF-beta1 in vitro.

The management of lower-extremity ulcers with zinc-saline wet dressings versus normal saline wet dressings

Rittenhouse T.
911 Medical Arts Building, 327 N. Washington Avenue, Scranton, PA 18503 USA
Advances in Therapy (USA), 1996, 13/2 (88-94)

Zinc-saline wet dressings were compared to normal-saline wet dressings for the management of lower extremity ulcers in a pilot study of 28 elderly patients. Although both study groups were comparable at baseline, the data suggest that the use of zinc-saline wet dressings creates a wound environment that is associated with trends toward faster healing and enhanced rates of epithelialization, as well as significantly more efficient wound management than the normal-saline controls. These data are presented in light of the requirement for maintaining a moist, acidic environment within a wound in order to permit the best possible healing and remodeling.

Glutamine homologues and derivatives: A limiting factor in current artificial nutrition?

Pesty F.; Sultan F.
Braun Medical S.A., 204 Avenue du Marechal Juin, 92107 Boulogne Cedex France
Nutrition Clinique et Metabolisme (France), 1996, 10/1 (7-17)

Glutamate, aspartate, arginine and glutamine can represent a third to half of the protein content in food and are the most amino acids rapidly cleared from plasma after IV administration. However, their abundance is limited in artificial nutrition. Along with alpha-ketoglutarate, ornithine, asparagine, oxalo-acetate, they can be defined as glutamine homologues and derivatives (GHD). Chemically, they share the same C4 and C5 carbons skeletons. GHD are biochemically interchangeable, but their synthesis from other substrates is quantitatively very limited and costly in energy. Thus, muscular proteolysis becomes the main source of GHD in the post-operative state. They play an important role in all processes requiring rapid cell division: wound healing, preservation of gut integrity, immune response, and growth in childhood. In addition, they participate in detoxication and neurotransmission in the brain. Experimental and clinical data suggest considering GHD content as a decisive criterion when choosing an amino acid solution for parenteral nutrition and probably also for enteral regimens. In human nutrition, they could be at least as efficient as glutamine, whose presence in parenteral mixtures is precluded by its poor stability. Enhanced supply for GHD can be achieved with glutamine dipeptides or ornithine alpha-ketoglutarate supplementation.

Nitric oxide is necessary for a switch from stationary to locomoting phenotype in epithelial cells

Noiri E.; Peresleni T.; Srivastava N.; Weber P.; Bahou W.F.; Peunova N.; Goligorsky M.S.
Dept. of Medicine, SUNY at Stony Brook, Stony Brook, NY 11794-8152 USA
American Journal of Physiology - Cell Physiology (USA), 1996, 270/3 39-3

The restitution of epithelial integrity is accomplished in part by cell migration. Studying this process, we have found that nitric oxide (NO) release from migrating epithelial BSC-1 cells displayed a biphasic response to the inflicted wounds; an initial transient release of NO is followed by a delayed sustained elevation. Whereas the constitutive endothelial NO synthase (NOS) did not show any spatial or temporal changes associated with wounding, the inducible NOS became expressed 3 h after wounding and showed higher abundance at the edges of epithelial wounds. L-Arginine (L-Arg) or NO-donor, S-nitroso-N-acetyl-DL-penicillamine, exerted motogenic effect in epithelial and endothelial cells. Inhibition of NOS with N(G)-nitro-L-arginine methyl ester (L-NAME) or a selective knockout of inducible NOS with antisense oligodeoxynucleotides reduced the rate of spontaneous or epidermal growth factor (EGF)-induced BSC-1 cell migration. Migrating cells showed the polarized expression of NOS, suggesting a head-to-rear NO gradient. Several growth factors (EGF, insulin-like growth factor I, hepatocyte growth factor, and fibroblast growth factor) were motogenic for BSC-1 cells, but this effect was abrogated by pretreatment with L-NAME. We conclude that endogenous NO production is a prerequisite for BSC-1 cell migration. A vectorial NO release may be essential for the spatially and temporally coordinated reciprocal phenomena that occur at the leading and trailing edge of locomoting epithelial cells. Although the exact mode of NO action remains uncertain, it is conceivable that the production of NO serves as a cellular switch from the stationary to the locomoting epithelial phenotype.

The effect of an arginine-glycine-aspartic acid peptide and hyaluronate synthetic matrix on epithelialization of meshed skin graft interstices

Cooper M.L.; Hansbrough J.F.; Polarek J.W.
FIBROGEN, 772 Lucerne Dr., Sunnyvale, CA 94086 USA
J Burn Care Rehabil 1996 Mar-Apr;17(2):108-16

Keratinocytes and fibroblasts interact with proteins of the extracellular matrix such as fibronectin and vitronectin through RGD (arginine-glycine- aspartic acid) cell-attachment sequences. This study evaluated the ability of a provisional synthetic matrix composed of an RGD peptide and hyaluronic acid to accelerate the epithelialization of the interstices of meshed, human, split-thickness skin when placed on full-thickness wounds of athymic mice. Full-thickness skin defects, sparing the panniculus carnosus, were created on athymic mice and 3:1 meshed, human skin was placed on them. The grafts had four central, isolated interstices, which epithelialized by migration of human keratinocytes. Conditions were either the addition to the wound of the synthetic matrix or a matrix of hyaluronic acid alone. The time to closure of the graft interstices was decreased (p < 0.02) in the wounds treated with the RGD peptide-hyaluronic acid provisional matrix. The resultant epithelium of the closed interstices was significantly thicker 8 days after surgery for the RGD-treated wounds. Basement membrane proteins (laminin and type IV collagen) were also found to be present at the dermoepidermal junction earlier in the RGD-treated wounds. These results imply that use of the RGD peptide conjugate to effect-cell-matrix interactions may have clinical significance in the field of wound healing.

Nutritional intake and status of clients in the home with open surgical wounds.

Stotts NA, Whitney JD
J Community Health Nurs 1990;7(2):77-86

The purpose of this study was to determine (a) whether the nutritional intake of patients at home with wounds healing by secondary intention was adequate to support healing, and (b) the nutritional status of these patients. Nineteen subjects with a mean age of 65.3 years were accrued. Of the 17 subjects for whom nutritional intake data were available, 16 had insufficient caloric intake to support healing and over half had less than the Recommended Daily Allowance (RDA) of protein. Using the RDA as a conservative measure of vitamin and mineral need with injury, Vitamin-C intake was decreased in approximately one third of the subjects, while all but one had decreased zinc intake. Over two thirds of the subjects reported a decrease from their usual weight and all the subjects measured had triceps skin fold (TSF) and mid-arm muscle circumference (MAMC) which were below the first and second Health and Nutrition Examination Surveys (HANES I & II) median. Mean serum albumin of the sample was below normal. The nutritional intake of these patients needs increased attention. Community health nurses (CHNs) need to assess nutritional status and monitor the intake of patients with wounds. Future research needs to address why intake is decreased and test strategies to increase oral intake.

High-dose Vitamin-C therapy for extensive deep dermal burns.

Matsuda T, Tanaka H, Shimazaki S, Matsuda H, Abcarian H, Reyes H, Hanumadass M
Hektoen Institute for Medical Research, Chicago, Illinois.
Burns 1992 Apr;18(2):127-31

We studied the haemodynamic effects of antioxidant therapy with high-dose Vitamin-C administration (170 mg/kg/24 h) in guinea-pigs with 70 per cent body surface area deep dermal burns. The animals were divided into three groups of six animals each. Group 1 was resuscitated with Ringer's lactate solution according to the Parkland formula; group 2 with 25 per cent of the Parkland formula with Vitamin-C; and group 3 with 25 per cent of the Parkland formula without Vitamin-C. There were no significant differences in heart rates or in blood pressures between the groups throughout the 24-h study period. Group 3 showed significantly higher haematocrit values at 3 h postburn and thereafter as compared with those of group 2. The cardiac output values of group 2 were significantly higher than those of group 3, but equivalent to those of group 1. The water content of the burned skin in group 2 was significantly lower than that in the other groups, indicating that increased postburn capillary permeability was minimized by the administration of Vitamin-C. With adjuvant high-dose Vitamin-C administration, we were able to reduce the 24-h resuscitation fluid volume from 4 ml/kg/per cent burn to 1 ml/kg/per cent burn, while maintaining adequate cardiac output.