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Many individuals with anxiety disorders use alcohol or cannabis for temporary relief of worry, sleeplessness, tension, and other typical anxiety symptoms. For some, this coping response can lead to worsening [...]

Hindlimb suspension (HLS) elicits muscle atrophy, oxidative stress, and apoptosis in skeletal muscle. Increases in oxidative stress can have detrimental effects on muscle mass and function, and it can potentially lead to myonuclear apoptosis. Resveratrol is a naturally occurring polyphenol possessing both antioxidant and antiaging properties. To analyze the capacity of resveratrol to attenuate oxidative stress, apoptosis and muscle force loss were measured following 14 days of HLS. Young (6 mo) and old (34 mo) rats were administered either 12.5 mg x [kg.sup.-1] x [day.sup.-1] of trans-resveratrol, or 0.1% carboxymethylcellulose for 21 days, including 14 days of HLS. HLS induced a significant decrease in plantarflexor isometric force, but resveratrol blunted this loss in old animals. Resveratrol increased gastrocnemius catalase activity, MnSOD activity, and MnSOD protein content following HLS. Resveratrol reduced hydrogen peroxide and lipid peroxidation levels in muscles from old animals after HLS. Caspase 9 abundance was reduced and Bcl-2 was increased, but other apoptotic markers were not affected by resveratrol in the gastrocnemius muscle after HLS. The data indicate that resveratrol has a protective effect against oxidative stress and muscle force loss in old HLS animals; however, resveratrol was unable to attenuate apoptosis following HLS. These results suggest that resveratrol has the potential to be an effective therapeutic agent to treat muscle functional decrements via improving the redox status associated with disuse. oxidative stress; apoptosis; hindlimb suspension; aging doi: 10.1152/ajpregu.00489.2010.

The study of free radicals is particularly relevant in the context of human skin carcinogenesis and photoaging because of their ability to induce DNA mutations and damaging lipid peroxidation byproducts. [...]

We hypothesized that the phytochemicals resveratrol, quercetin, and kaempferol would modulate B lymphocyte proliferation, Ig synthesis, and apoptosis after activation. Peripheral blood mononuclear cells (PBMC) were isolated from 12 healthy adult human volunteers and incubated with pokeweed mitogen plus 0, 2, 5, and 10 [micro]mol/L resveratrol, quercetin, or kaempferol. After 6 d, CD19+ B cells were analyzed for proliferation, B cell lymphoma-2 (Bcl-2) expression, and activation of caspase-3 using flow cytometry. After 8 d, cell supernatants were collected and IgM and IgG were measured by ELISA. Resveratrol at a concentration of 5 [micro]mol/L increased the percentage of CD19+ cells compared with mitogen only-stimulated cells (P < 0.01), and a trend for increased proliferation was observed for cells treated with 0, 2, and 5 [micro]mol/L resveratrol (P-trend = 0.01). However, 10 [micro]mol/L resveratrol inhibited proliferation of B lymphocytes (P < 0.01). Expression of Bcl-2 and caspase-3 activation increased in B cells treated with 10 [micro]mol/L resveratrol compared with mitogen alone (P < 0.01), and trends for dose-responsive increases in Bcl-2 expression and caspase-3 activation were observed (P-trend < 0.0001). Differences in IgM and IgG production were not observed for PBMC treated with resveratrol. Kaempferol at 10 [micro]mol/L slightly inhibited proliferative responses (P < 0.05) but did not affect B cell function or apoptosis. Quercetin did not alter B cell proliferation, function, or apoptosis. These data show that human B lymphocyte proliferation and apoptosis are modified by physiological concentrations of resveratrol and suggest that exposure of human B cells to resveratrol may increase survival by upregulating Bcl-2. J. Nutr. 139: 1603-1608, 2009.

Sirtuin1 (Sirt1) is a NAD-dependent deacetylase that plays important roles in a variety of biological processes. In the current study, we examined tissue-specific and different expression pattern of porcine Sirt1 and the effect of resveratrol (RES) on expression of Sirt1 in porcine adipocytes. The full-length complementary DNA sequence of porcine Sirt1 was 4,024 bp (GenBank accession no: EU030283), with a 2,226-bp open reading frame encoding a 742-AA protein (a predicted molecular mass of 80.9 kDa; GenBank accession no. ABS29571). Comparison of the deduced AA sequence with the corresponding sequences of human, dog, cattle, and mouse Sirt1 showed 82 to 92% similarity. Furthermore, the porcine Sirt1 was highly expressed in porcine brain, to a lesser degree in spleen and white adipose tissue, and had low but detectable expression in liver. In subcutaneous adipose tissue and omental adipose tissue, expression of the porcine Sirt1 mRNA was greater in adult pigs than in young pigs (P < 0.01). In vitro, exposure of cultured adipocytes to 40 and 80 [micro]M RES for 24 h increased mRNA levels of porcine Sirt1 by 47.86% (P < 0.01) and 91.04% (P < 0.01), respectively. Accordingly, lipid accumulation and NEFA release were decreased (P < 0.05), respectively. After cultures were treated with RES for 48 h, the mRNA level of porcine Sirt1 was increased by 103.84% (P < 0.01) and 148.79% (P < 0.01), respectively. Lipid accumulation was decreased and NEFA release was increased (P < 0.05), respectively. These results provide information needed for manipulating Sirt1 expression in regulating fat deposition in pigs. Key words: cloning, gene expression, pig, resveratrol, sirtuin 1

Studies show that the plant polyphenol resveratrol can extend the life span of yeast, worms, flies, and fish. It also mitigates the metabolic dysfunction of mice fed high-fat diets. Resveratrol appears to mediate these effects partly by activating SIRT1, a deacetylase enzyme that regulates the activity of several transcriptional factors and enzymes responsive to nutrient availability. However, few foods contain resveratrol and humans metabolize it extensively, resulting in very low systemic bioavailability. Substantial research effort now focuses on identifying and testing more bioavailable and potent activators of SIRT1 for use as pharmacologic interventions in aging and age-related disorders.

Alcoholic fatty liver is associated with inhibition of sirtuin 1 (SIRT1) and AMP-activated kinase (AMPK), two critical signaling molecules regulating the pathways of hepatic lipid metabolism in animals. Resveratrol, a dietary polyphenol, has been identified as a potent activator for both SIRT1 and AMPK. In the present study, we have carried out in vivo animal experiments that test the ability of resveratrol to reverse the inhibitory effects of chronic ethanol feeding on hepatic SIRT1-AMPK signaling system and to prevent the development of alcoholic liver steatosis. Resveratrol treatment increased SIRT1 expression levels and stimulated AMPK activity in livers of ethanol-fed mice. The resveratrol-mediated increase in activities of SIRT1 and AMPK was associated with suppression of sterol regulatory element binding protein 1 (SREBP-) and activation of peroxisome proliferator-activated receptor [gamma] coactivator a (PGC-1[alpha]). In parallel, in ethanol-fed mice, resveratrol administration markedly increased circulating adiponectin levels and enhanced mRNA expression of hepatic adiponectin receptors (AdipoR1/R2). In conclusion, resveratrol treatment led to reduced lipid synthesis and increased rates of fatty acid oxidation and prevented alcoholic liver steatosis. The protective action of resveratrol is in whole or in part mediated through the upregulation of a SIRT1-AMPK signaling system in the livers of ethanol-fed mice. Our study suggests that resveratrol may serve as a promising agent for preventing or treating human alcoholic fatty liver disease. alcoholic liver steatosis; lipid metabolism; sirtuin 1; AMP-activated kinase; acetylation; sterol regulatory element-binding protein 1c; peroxisome proliferator-activated receptor [gamma] coactivator [alpha]