ALOE JUICE
Activation of a mouse macrophage cell line by acemannan: The major carbohydrate fraction from Aloe vera gel
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
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
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
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
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
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
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
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.
Aloe vera (gel) cream as a topical treatment for outpatient burns
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.
Acemannan Immunostimulant in combination with surgery and radiation therapy on spontaneous canine and feline fibrosarcomas.
J Am Anim Hosp Assoc; 31(5):439-47 1995
Eight dogs and five cats with histopathologically confirmed fibrosarcomas were treated with Acemannan Immunostimulanta in combination with surgery and radiation therapy. These animals had recurring disease that had failed previous treatment, a poor prognosis for survival, or both. Following four to seven weekly acemannan treatments, tumor shrinkage occurred in four (greater than 50%; n = 2) of 12 animals, with tumors accessible to measurement. A notable increase in necrosis and inflammation was observed. Complete surgical excision was performed on all animals between the fourth and seventh week following initiation of acemannan therapy. Radiation therapy was instituted immediately after surgery. Acemannan treatments were continued monthly for one year. Seven of the 13 animals remain alive and tumor-free (range, 440+ to 603+ days) with a median survival time of 372 days. The data suggests that Acemannan Immunostimulant may be an effective adjunct to surgery and radiation therapy in the treatment of canine and feline fibrosarcomas.
Acemannan-containing wound dressing gel reduces radiation-induced skin reactions in C3H mice.
Int J Radiat Oncol Biol Phys; 32(4):1047-52 1995
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.
Partial purification and some properties of an antibacterial compound from Aloe vera
PHYTOTHER. RES. (United Kingdom), 1988, 2/2 (67-69)
Aqueous or ethanolic extracts of Aloe leaves were examined for antibacterial properties. The crude extrudes strongly stimulated bacterial growth. Separation of various fractions by thin layer chromatography (TLC) resulted in a fraction which inhibited the growth of Bacillus subtilis. A concomitant examination of protein and nucleic acisynthesis in B. subtilis in the presence of the inhibitory compound indicated that the plant extract inhibits primarily nucleic acid synthesis, after which protein synthesis is also inhibited. The inhibitor seemed to be present in all examined Aloe species but at different concentrations. On a dry weight basis, the inhibitory effect was equally distributed between the skin and the gel fraction.
Comparative evaluation of aloe vera in the management of burn wounds in guinea pigs
PLAST. RECONSTR. SURG. (USA), 1988, 81/3 (386-389)
An experimental study was designed using Hartley guinea pigs, who received full-thickness burns covering 3 percent of their body surface area by direct contact with a hot plate. A total of 40 animals were equally divided among four modalities of closed burn wound management as follows: group I: silver sulfadiazine (Silvadine); group II: aloe vera gel extract (Carrington Dermal Wound Gel); group III: salicyclic acid cream (aspirin); and group IV: plain gauze occlusive dressing only. The dressings were changed daily, and the size and appearance of each burn wound were recorded until complete healing. On the sixth postburn day, quantitative burn wound cultures were made. The average time to complete healing in the control group was 50 days, and the only significant difference was found in the aloe vera-treated animals, which healed on an average of 30 days (p < 0.02). Wound bacterial counts were effectively decreased by silver sulfadiazine (p = 0.015) and by aloe vera extract (p = 0.015). From our data it appears that aloe gel extracts permit a faster healing of burn wounds.
