SUMMARY A small molecule that safely mimics the ability of dietary restriction (DR) to delay age-related diseases in laboratory animals is greatly sought after. We and others have shown that resveratrol mimics effects of DR in lower organisms. In mice, we find that resveratrol induces gene expression patterns in multiple tissues that parallel those induced by DR and every-other-day feeding. Moreover, resveratrol-fed elderly mice show a marked reduction in signs of aging including reduced albuminuria, decreased inflammation and apoptosis in the vascular endothelium, increased aortic elasticity, greater motor coordination, reduced cataract formation, and preserved bone mineral density. However, mice fed a standard diet did not live longer when treated with resveratrol beginning at 12 months of age. Our findings indicate that resveratrol treatment has a range of beneficial effects in mice but does not increase the longevity of ad libitum-fed animals when started mid-life.

Abstract-We aimed to elucidate the possible role of phenotypic alterations and oxidative stress in age-related endothelial dysfunction of coronary arterioles. Arterioles were isolated from the hearts of young adult (Y, 14 weeks) Key Words: arteriole Ⅲ endothelium Ⅲ superoxide Ⅲ reactive oxygen species Ⅲ free radical scavenger N umerous studies suggest that aging is an important risk factor for the development of ischemic heart disease. This may be due to an age-related increase in coronary vascular resistance, 1 leading to a reduction in myocardial blood flow and flow reserve. 1,2 Studies utilizing pharmacological probes, such as acetylcholine (ACh), suggest that aging is associated with endothelial dysfunction in humans 3,4 and in laboratory animals. 5,6 One of the most important mechanisms that contribute to the local regulation of myocardial blood flow is the flow (shear stress)-induced NOmediated dilation of small coronary arteries and arterioles 7 ; however, its age-related alterations have not yet been elucidated. Previous studies demonstrated that pathophysiological conditions that are associated with an increased risk of coronary heart disease, such as hypercholesterolemia, diabetes, hypertension, and hyperhomocysteinemia, are characterized by decreased NO synthesis/release and a significant impairment of flow-induced dilation of arterioles. 8 -10 Thus, it can be hypothesized that aging may also impair NO synthesis/release in the coronary endothelium by decreasing availability of the eNOS substrate L-arginine 11 or by decreasing the activity of eNOS. 12 Also, there may be an increased breakdown of NO due to an augmented arteriolar production of superoxide (O 2 ·Ϫ ) anions 13 or a loss of antioxidant capacity, which normally provides protection against reactive oxygen species (oxidative stress, reviewed in Beckman and Ames 14 ). In addition, age-related dysfunction in some conduit vessels may involve an enhanced synthesis of thromboxane A 2 (TXA 2 ), 5 suggesting that the underlying mechanisms associated with vascular aging are multifactorial with significant anatomic heterogeneity. 6 Recent studies showing that aging significantly alters regulation of gene expression by hormonal and growth factors 15 raise the possibility that complex phenotypic changes affecting expression of eNOS 6 and/or a shift in the expression of pro-and antioxidant enzymes 6,12,13,16 may elicit age-related decreases in NO bioavailability.To test the hypothesis that aging is associated with impaired NO-mediation of flow-induced dilation due to an increased production of superoxide (which scavenges NO) or TXA 2 (which may counteract the effect of NO), we characterized in isolated coronary arterioles age-related alterations in flow-induced dilation, O 2 ·Ϫ production, peroxynitrite generation, 17 and expression of eNOS and the pro-and antioxi-

Aging of the vasculature plays a central role in morbidity and mortality of older people. In order to develop novel treatments for amelioration of unsuccessful vascular aging and prevention of age-related vascular pathologies it is essential to understand the cellular and functional changes that occur in the vasculature during aging. In this review, the pathophysiological roles of fundamental cellular and molecular mechanisms of aging, including oxidative stress, mitochondrial dysfunction, impaired resistance to molecular stressors, chronic low-grade inflammation, genomic instability, cellular senescence, epigenetic alterations, loss of protein homeostasis, deregulated nutrient sensing and stem cell dysfunction in the vascular system are considered in terms of their contribution to the pathogenesis of both micro- and macrovascular diseases associated with old age. The importance of pro-geronic and anti-geronic circulating factors in relation to development of vascular aging phenotypes are discussed. Finally, future directions and opportunities to develop novel interventions to prevent/delay age-related vascular pathologies by targeting fundamental cellular and molecular aging processes are presented.

This review focuses on molecular, cellular, and functional changes that occur in the vasculature during aging; explores the links between mitochondrial oxidative stress, inflammation, and development of vascular disease in the elderly patients; and provides a landscape of molecular mechanisms involved in cellular oxidative stress resistance, which could be targeted for the prevention or amelioration of unsuccessful vascular aging. Practical interventions for prevention of age-associated vascular dysfunction and disease in old age are considered here based on emerging knowledge of the effects of anti-inflammatory treatments, regular exercise, dietary interventions, and caloric restriction mimetics.

Epidemiological studies suggest that Mediterranean diets rich in resveratrol are associated with reduced risk of coronary artery disease. Resveratrol was also shown to confer vasoprotection in animal models of type 2 diabetes and aging. However, the mechanisms by which resveratrol exerts its antioxidative vasculoprotective effects are not completely understood. Using a nuclear factor-E(2)-related factor-2 (Nrf2)/antioxidant response element-driven luciferase reporter gene assay, we found that in cultured coronary arterial endothelial cells, resveratrol, in a dose-dependent manner, significantly increases transcriptional activity of Nrf2. Accordingly, resveratrol significantly upregulates the expression of the Nrf2 target genes NAD(P)H:quinone oxidoreductase 1, gamma-glutamylcysteine synthetase, and heme oxygenase-1. Resveratrol treatment also significantly attenuated high glucose (30 mM)-induced mitochondrial and cellular oxidative stress (assessed by flow cytometry using MitoSox and dihydroethidine staining). The aforementioned effects of resveratrol were significantly attenuated by the small interfering RNA downregulation of Nrf2 or the overexpression of Kelch-like erythroid cell-derived protein 1, which inactivates Nrf2. To test the effects of resveratrol in vivo, we used mice fed a high-fat diet (HFD), which exhibit increased vascular oxidative stress associated with an impaired endothelial function. In HFD-fed Nrf2(+/+) mice, resveratrol treatment attenuates oxidative stress (assessed by the Amplex red assay), improves acetylcholine-induced vasodilation, and inhibits apoptosis (assessed by measuring caspase-3 activity and DNA fragmentation) in branches of the femoral artery. In contrast, the aforementioned endothelial protective effects of resveratrol were diminished in HFD-fed Nrf2(-/-) mice. Taken together, our results indicate that resveratrol both in vitro and in vivo confers endothelial protective effects which are mediated by the activation of Nrf2.