Life Extension Magazine February 2009
High omega-3 fat intake improves insulin sensitivity and reduces CRP and IL6, but does not affect other endocrine axes in healthy older adults.
Aging diminishes hormone secretion and target cell responsiveness, possibly due to loss of cell membrane fluidity or alteration of membrane phospholipids affecting signal transduction. We investigated whether a high omega-3 polyunsaturated fatty acid diet would improve endocrine function in 6 men and 6 women aged over 60 years. Subjects first ate an isocaloric control diet for 6 weeks, followed by an 8-week experimental diet, which included 720 g of fatty fish weekly plus 15 ml of sardine oil daily. In the last week, we measured RBC membrane fatty acids on each diet, performed pituitary, adrenal, hepatic, and Leydig cell endocrine provocative testing, and assayed selected cytokines. We also assessed insulin sensitivity utilizing octreotide insulin suppression testing and assessed free fatty acid (FFA) responses to isoproteronol. Insulin sensitivity increased significantly after 8 weeks on the omega-3 diet and FFA responses trended lower. Serum C-reactive protein was significantly reduced and a trend towards lower IL-6 was noted. No differences were found in other metabolic parameters, adiponectin levels, or hormone responses. We conclude that, in older people, high omega-3 consumption increases insulin sensitivity, may reduce FFA mobilization by catecholamines, and reduces inflammatory markers, but did not alter endocrine responsiveness after 8 weeks.
Horm Metab Res. 2008 Mar;40(3):199-205
Chemokines in cardiovascular risk prediction.
In consideration of the important role of inflammation in plaque progression and stability, recent work has focused on whether plasma markers of inflammation can non-invasively diagnose and predict coronary artery disease (CAD) and other forms of atherosclerotic disorders. Although several studies support an important pathogenic role of chemokines in atherogenesis and plaque destabilization, potentially representing attractive therapeutic targets in atherosclerotic disorders, this does not necessarily mean that chemokines are suitable parameters for risk prediction. In fact, the ability to reflect up-stream inflammatory activity, stable levels in individuals and high stability of the actual protein (e.g. long half-life and negligible circadian variation), are additional important criteria for an ideal biomarker in cardiovascular disease. Although plasma/serum levels of certain chemokines (e.g. interleukin 8 and monocyte chemoattractant protein-1) have been shown to be predictive for future cardiac events in some studies, independent of traditional cardiovascular risk factors and C-reactive protein, and although certain gene polymorphisms of chemokines/chemokine receptors (e.g. fractalkine receptor) have been shown to be predictive of future atherosclerotic disease, further prospective studies, including a larger number patients, are needed to make any firm conclusion. While the demonstrations of an association between chemokines and CAD are a necessary first step, such studies do not establish the full clinical utility of a biomarker, which is a more demanding process that requires validation in multiple cohorts, and clear demonstration of incremental prognostic value over traditional risk models. If successful, such new biomarker will be a useful indicator for better risk assessment, diagnosis, and prognosis, as well as monitoring pharmacological treatments for atherosclerosis.
Thromb Haemost. 2007 May;97(5):748-54
Characteristics of catechin- and theaflavin-mediated cardioprotection.
Catechins and theaflavins-the main polyphenolic substances of green and black tea, respectively-exert a plethora of beneficial effects on the cardiovascular system. In a model of H(2)O(2)-mediated oxidative stress, we investigated the effects of epigallocatechin-3-gallate (EGCG) and theaflavin-3,3’-digallate (TF3) on neonatal rat cardiomyocytes. Pretreatment with EGCG or TF3 1 hr prior to induction of oxidative stress by H(2)O(2) effectively protected cardiac myocytes as determined by measuring release of lactate dehydrogenase after 24 hrs. Longer pre-incubation times resulted in significant loss of protection. To enable further mechanistic insight, we investigated expression of antioxidative enzymes and activation of prosurvival signaling cascades. Whereas mRNA levels of glutathione peroxidase 3, superoxide dismutase 1, and catalase were not influenced by both polyphenols, heme oxygenase (HO-1) was selectively upregulated by EGCG-but not by TF3. However, inhibition of HO-1 did not diminish polyphenol-mediated cardioprotection. While EGCG and TF3 activated Akt, extracellular signal-regulated kinase 1/2, and p38 mitogen-activated protein kinase, inhibition of these kinases did not attenuate polyphenol-mediated protection. Loading of cardiomyocytes with dichlorofluorescein revealed that intracellular levels of reactive oxygen species were significantly reduced after treatment with EGCG or TF3 as early as 30 mins after induction of oxidative stress. In conclusion, activation of prosurvival signaling kinases and upregulation of antioxidative enzymes do not play a major role in tea polyphenol-mediated cardioprotection.
Exp Biol Med (Maywood). 2008 Apr;233(4):427-33
The efficacy of black tea in ameliorating endothelial function is equivalent to that of green tea.
Consumption of tea has been shown to improve endothelial function. It is assumed that catechins are the tea components responsible for these beneficial effects. In black tea, catechin concentrations are significantly lower than in green tea. The present study was designed to compare green and black tea with regard to amelioration of endothelial function. Endothelial function in response to both teas was assessed in bovine aortic endothelial cells (BAEC) and rat aortic rings. To elucidate whether these findings are also applicable to humans, flow-mediated dilation (FMD) and nitro-mediated dilation (NMD) were assessed by ultrasound in twenty-one healthy women before and 2 h after consumption of green and black tea (2 h of FMD and NMD), in comparison with water (control). In BAEC, green and black tea significantly increased endothelial NO synthase activity to the same extent. Similarly, both teas induced comparable endothelial-dependent vasodilation in rat aortic rings. In human subjects, ingestion of green and black tea led to significant increases in FMD: from 5.4 (sd 2.3) to 10.2 (sd 3) % (baseline-adjusted difference (BAD) for 2 h of FMD, green tea v. water: 5.0 (95 % CI 3.0, 7.0) %; P < 0.001) and from 5 (sd 2.6) to 9.1 (sd 3.6) % (BAD for 2 h of FMD, black tea v. water: 4.4 (95 % CI 2.3, 6.5) %; P < 0.001), respectively. The increase in FMD was not significantly different between the two tea preparations (BAD for 2 h of FMD, green tea v. black tea: 0.66 (95 % CI - 0.76, 2.09) %; P = 0.36). NMD did not vary between any of the groups. In conclusion, green and black tea are equally effective in improving endothelial function.
Br J Nutr. 2008 Apr;99(4):863-8
Rosuvastatin to prevent vascular events in men and women with elevated C-reactive protein.
BACKGROUND: Increased levels of the inflammatory biomarker high-sensitivity C-reactive protein predict cardiovascular events. Since statins lower levels of high-sensitivity C-reactive protein as well as cholesterol, we hypothesized that people with elevated high-sensitivity C-reactive protein levels but without hyperlipidemia might benefit from statin treatment. METHODS: We randomly assigned 17,802 apparently healthy men and women with low-density lipoprotein (LDL) cholesterol levels of less than 130 mg per deciliter (3.4 mmol per liter) and high-sensitivity C-reactive protein levels of 2.0 mg per liter or higher to rosuvastatin, 20 mg daily, or placebo and followed them for the occurrence of the combined primary end point of myocardial infarction, stroke, arterial revascularization, hospitalization for unstable angina, or death from cardiovascular causes. RESULTS: The trial was stopped after a median follow-up of 1.9 years (maximum, 5.0). Rosuvastatin reduced LDL cholesterol levels by 50% and high-sensitivity C-reactive protein levels by 37%. The rates of the primary end point were 0.77 and 1.36 per 100 person-years of follow-up in the rosuvastatin and placebo groups, respectively (hazard ratio for rosuvastatin, 0.56; 95% confidence interval [CI], 0.46 to 0.69; P<0.00001), with corresponding rates of 0.17 and 0.37 for myocardial infarction (hazard ratio, 0.46; 95% CI, 0.30 to 0.70; P=0.0002), 0.18 and 0.34 for stroke (hazard ratio, 0.52; 95% CI, 0.34 to 0.79; P=0.002), 0.41 and 0.77 for revascularization or unstable angina (hazard ratio, 0.53; 95% CI, 0.40 to 0.70; P<0.00001), 0.45 and 0.85 for the combined end point of myocardial infarction, stroke, or death from cardiovascular causes (hazard ratio, 0.53; 95% CI, 0.40 to 0.69; P<0.00001), and 1.00 and 1.25 for death from any cause (hazard ratio, 0.80; 95% CI, 0.67 to 0.97; P=0.02). Consistent effects were observed in all subgroups evaluated. The rosuvastatin group did not have a significant increase in myopathy or cancer but did have a higher incidence of physician-reported diabetes. CONCLUSIONS: In this trial of apparently healthy persons without hyperlipidemia but with elevated high-sensitivity C-reactive protein levels, rosuvastatin significantly reduced the incidence of major cardiovascular events.
N Engl J Med. 2008 Nov 20;359(21):2195-207
Inflammation is a crucial feature of atherosclerosis and a potential target to reduce cardiovascular events.
Contrary to popular opinion, atherosclerosis is not a disease unique to modern civilization. In fact, atherosclerotic lesions have been found in the arteries of mummies dating back to 1,500 B.C., and yet our understanding of this complex process is still evolving. A fusion of basic science advances and clinical research findings has radically altered our traditional concepts about the pathogenesis and treatment of the clinical complications of atherosclerosis. Most physicians previously regarded the artery as a being merely a blood conduit that became encrusted with lipid detritus as part of the aging process. Modern-day treatment of atherosclerosis has arisen primarily from an understanding of the epidemiology of the disease rather than its pathophysiology, in that risk factors have traditionally been targeted. Our concepts of atherogenesis have evolved from vague ideas of inevitable degeneration to a much better defined scenario of molecular and cellular events. As we enhance our understanding of its fundamental mechanism, we can begin to approach atherogenesis as a modifiable rather than ineluctable process. Indeed, as we recognize now that inflammation plays a pivotal role in the process of atherosclerosis, it is noteworthy to evaluate the effect of modern therapies on this facet of the disease.
Handb Exp Pharmacol. 2005;(170):697-722
Inflammaging as a major characteristic of old people: can it be prevented or cured?
Widespread aging at the population level is a recent phenomenon that emerged in affluent societies. Inflammation is necessary to cope with damaging agents and is crucial for survival, particularly to cope with acute inflammation during our reproductive years. But chronic exposure to a variety of antigens, especially to some viruses such as cytomegalovirus, for a period much longer than that predicted by evolution, induces a chronic low-grade inflammatory status that contributes to age-associated morbidity and mortality. This condition carries the proposed name “inflammaging.” Centenarians are unique in that, despite high levels of pro-inflammatory markers, they also exhibit anti-inflammatory markers that may delay disease onset. The key to successful aging and longevity is to decrease chronic inflammation without compromising an acute response when exposed to pathogens.
Nutr Rev. 2007 Dec;65(12 Pt 2):S173-6
Achieving and maintaining cognitive vitality with aging.
Cognitive vitality is essential to quality of life and survival in old age. With normal aging, cognitive changes such as slowed speed of processing are common, but there is substantial interindividual variability, and cognitive decline is clearly not inevitable. In this review, we focus on recent research investigating the association of various lifestyle factors and medical comorbidities with cognitive aging. Most of these factors are potentially modifiable or manageable, and some are protective. For example, animal and human studies suggest that lifelong learning, mental and physical exercise, continuing social engagement, stress reduction, and proper nutrition may be important factors in promoting cognitive vitality in aging. Manageable medical comorbidities, such as diabetes, hypertension, and hyperlipidemia, also contribute to cognitive decline in older persons. Other comorbidities such as smoking and excess alcohol intake may contribute to cognitive decline, and avoiding these activities may promote cognitive vitality in aging. Various therapeutics, including cognitive enhancers and protective agents such as antioxidants and anti-inflammatories, may eventually prove useful as adjuncts for the prevention and treatment of cognitive decline with aging. The data presented in this review should interest physicians who provide preventive care management to middle-aged and older individuals who seek to maintain cognitive vitality with aging.
Mayo Clin Proc. 2002 Jul;77(7):681-96
Immunoproteasomes and immunosenescence.
Aging is a complex process which is accompanied with the decline and the reshaping of different functions of the body. In particular the immune system is characterized, during ageing (immunosenescence) by a remodeling of innate immunity (well preserved, up-regulated) and clonotypical immunity (severely altered) and by the occurrence of a chronic inflammatory process (inflammaging) which are, at least in part, genetically controlled. In this scenario, it can be anticipated that a crucial role is played by age-related structural and functional alterations and modifications of proteasomes and immunoproteasomes, the last being a key component of antigen processing and MHC class I antigen presentation. A variety of experimental data are available, suggesting that proteasomes are affected by age, and that in centenarians they are relatively preserved. On the contrary, few data are available on immunoproteasomes, likely as a consequence of the poverty of suitable cellular models. Lymphoblastoid cell lines from EBV immortalized B cells from old donors is envisaged as a possible model for the study of immunoproteasomes in humans and their changes with age. Thus, basic questions such as those related to possible consequences, for immune responses in infectious diseases and cancer, of age-related alterations of antigen processing and presenting, change with age of self-antigen repertoire, and the genetic basis of immunoproteasome activity and its change with age, remain largely unanswered.
Ageing Res Rev. 2003 Oct;2(4):419-32
Is inflammaging an auto[innate]immunity subclinical syndrome?
The low-grade, chronic, systemic inflammatory state that characterizes the aging process (inflammaging) results from late evolutive-based expression of the innate immune system. Inflammaging is characterized by the complex set of five conditions which can be described as 1. low-grade, 2. controlled, 3. asymptomatic, 4. chronic, 5. systemic, inflammatory state, and fits with the antagonistic pleiotropy theory on the evolution of aging postulating that senescence is the late deleterious effect of genes (pro-inflammatory versus anti-inflammatory) that are beneficial in early life. Evolutionary programming of the innate immune system may act via selection on these genetic traits. Here I propose that the already acquired knowledge in this field may pave the way to a new chapter in the pathophysiology of autoimmunity: the auto-innate-immunity syndromes. Indeed, differently from the well known chapter of conventional autoimmune diseases and syndromes where the main actor is the adaptive immunity, inflammaging may constitute the subclinical paradigm of a new chapter of autoimmunity, namely that arising from an autoimmune inflammatory response of the innate-immune-system, an old actor of immunity and yet a new actor of autoimmunity, also acting as a major determinant of elderly frailty and age-associated diseases.
Immun Ageing. 2006 Dec 16;3:12
Role of environmental and genetic factor interaction in age-related disease development: the gastric cancer paradigm.
The association of Helicobacter pylori (Hp) infection with gastric cancer is well known and might be considered a paradigmatic example of the role that interaction among environmental factors and individual background might play in inducing age-associated disease. To evaluate the role of interaction of Hp infection with genetic background, gastric cancer and chronic gastritis patients as well as random selected controls were typed for five inflammation-related polymorphisms of IL-1 and IL-10 cytokine genes. No association among IL-10 or IL-1 variants with an increased risk of gastric cancer was found, whereas an Hp-independent association of IL-1beta -511T positive genotypes to an increased risk of chronic gastritis was found (Hp-/511T+ OR 1.89, 95% CI: 1.01-3.54; Hp+/-511T+ OR 1.83, 95% CI: 1.05-3.19). Stratification of gastric cancer group according to Hp infection does not allow finding a statistically significant association of Hp+ to the higher histological grading (G3) of gastric cancer (OR 1.54, 95% CI: 0.46-5.11). Our findings seem to confirm that cytokine genetic variants might contribute to determining the background for inflammaging in which H. pylori infection might facilitate cancer development.
Rejuvenation Res. 2008 Apr;11(2):509-12
The effect of age and telomere length on immune function in the horse.
Telomeres, specialized structures present at the ends of linear eukaryotic chromosomes, function to maintain chromosome stability and integrity. Telomeres shorten with each cell division eventually leading to replicative senescence, a process thought to be associated with age-related decline in immune function. We hypothesized that shortened PBMC telomere length is a factor contributing to immunosenescence of the aged horse. Telomere length was assessed in 19 horses ranging in age from 1 to 25 years. Mitogen-induced 3H-thymidine incorporation, total serum IgG, and pro-inflammatory cytokine expression was also determined for each horse. Relative telomere length (RTL) was highly correlated with overall age. RTL was positively correlated with 3H-thymidine incorporation and total IgG. Expression of pro-inflammatory cytokines was negatively correlated with RTL. These measures were also correlated with age, as expected. However, RTL was not correlated with immunosenescence and inflammaging in the oldest horse.
Dev Comp Immunol. 2008;32(12):1409-15
Relative safety profiles of high dose statin regimens.
Recent clinical trials recommend achieving a low-density lipoprotein cholesterol level of <100 mg/dl in high-risk and <70 mg/dl in very high risk patients. To attain these goals, however, many patients will need statins at high doses. The most frequent side effects related to the use of statins, myopathy, rhabdomyolysis, and increased levels of transaminases, are unusual. Although low and moderate doses show a favourable profile, there is concern about the tolerability of higher doses. During recent years, numerous trials to analyze the efficacy and tolerability of high doses of statins have been published. This paper updates the published data on the safety of statins at high doses.
Vasc Health Risk Manag. 2008;4(3):525-33
Effect of Chyawanprash and vitamin C on glucose tolerance and lipoprotein profile.
Chyawanprash is an ancient Indian dietary supplement containing vitamin C (34 mg/100 g) derived from amla (Emblica officinalis). In addition, Chyawanprash also contains several other herbal products. The present study was designed to compare the effects of vitamin C with those of Chyawanprash. Ten normal healthy adult male volunteers (age 20-32 years) participated in the 16-week study. They were placed randomly in either the Chyawanprash group (n = 5) or vitamin C group (n = 5). Those in the former received 15 g/d of Chyawanprash while those in the latter received 500 mg/d vitamin C during the first 8 weeks of the study. For the next 8 weeks, no supplement was given. For each individual, an oral glucose tolerance test was performed, and lipoprotein profile in peripheral serum samples was determined at 0 weeks, 4 weeks, 8 weeks, 12 weeks and 16 weeks. In the Chyawanprash group, the 8 weeks Vs 0 weeks value (mean +/- S.D.) respectively for various indices which were significantly different were fasting plasma glucose (100.2 +/- 5.58 mg/dl vs 116.2 +/- 11.6 mg/dl), area under 2-h plasma glucose curve (245.9 +/- 15.13 mg.dl-1.h vs 280.8 +/- 37.09 mg.dl-1.h), HDL cholesterol (53.2 +/- 4.56 mg/dl vs 42.7 +/- 7.17 mg/dl), LDL cholesterol (82.4 +/- 8.80 mg/dl vs 98.26 +/- 12.07 mg/dl), LDL/HDL ratio (1.56 +/- 0.28 vs 2.38 +/- 0.63). In the Vitamin C group, only the LDL/HDL ratio was significantly lower at 8 weeks than at 0 weeks (1.99 +/- 0.44 vs 2.29 +/- 0.43). All the variables that changed significantly were no longer significantly different from the 0 weeks value at 16 weeks. Chyawanprash reduces postprandial glycemia in the oral glucose tolerance test and reduces blood cholesterol level to a significantly greater extent than vitamin C.
Indian J Physiol Pharmacol. 2001 Jan;45(1):71-9
Mechanisms of cancer prevention by green and black tea polyphenols.
Drinking green tea is associated with decreased frequency of cancer development. This review outlines the wide range of mechanisms by which epigallocatechin gallate (ECGC) and other green and black tea polyphenols inhibit cancer cell survival. EGCG suppressed androgen receptor expression and signalling via several growth factor receptors. Cell cycle arrest or apoptosis involved caspase activation and altered Bcl-2 family member expression. EGCG inhibited telomerase activity and led to telomere fragmentation. While at high concentrations polyphenols had pro-oxidative activities, at much lower levels, anti-oxidative effects occurred. Nitric oxide production was reduced by EGCG and black tea theaflavins by suppressing inducible nitric oxide synthase via blocking nuclear translocation of the transcription factor nuclear factor-kappaB as a result of decreased IkappaB kinase activity. Polyphenols up- or down-regulated activity of a number of key enzymes, including mitogen-activated protein kinases and protein kinase C, and increased or decreased protein/mRNA levels, including that of cyclins, oncogenes, and tumor suppressor genes. Metastasis was inhibited via effects on urokinase and matrix metalloproteinases. Polyphenols reduced angiogenesis, in part by decreasing vascular endothelial growth factor production and receptor phosphorylation. Recent work demonstrated that EGCG reduced dihydrofolate reductase activity, which would affect nucleic acid and protein synthesis. It also acted as an aryl hydrocarbon receptor an-tagonist by directly binding the receptor’s molecular chaperone, heat shock protein 90. In conclusion, green and black tea polyphenols act at numerous points regulating cancer cell growth, survival, and metastasis, including effects at the DNA, RNA, and protein levels.
Anticancer Agents Med Chem. 2006 Sep;6(5):389-406