Project description:The SIRT1 deacetylase is one of the best-studied potential mediators of some of the anti-aging effects of calorie restriction (CR); but its role in CR-dependent lifespan extension has not been demonstrated. We previously found that mice lacking both copies of SIRT1 displayed a shorter median lifespan than wild type mice on an ad libitum diet. Here we report that median lifespan extension in CR heterozygote SIRT1+/- mice was identical (51%) to that observed in wild type mice but SIRT1+/- mice displayed a higher frequency of some certain pathologies. Although larger studies in different genetic backgrounds are necessary , these results provide strong initial evidence for the requirement of SIRT1 for the anti-aging effects of CR, but suggest that its high expression is not required for CR-induced lifespan extension. Key words: SIRT1, caloric restriction, lifespan, anti-aging 2-5 month old male mice of 3 different genotypes (SIRT1+/+, SIRT1+/-, and SIRT1-/-) that had normal, reduced or no expression of SIRT1 were treated with either a 40% caloric restricted diet (CR) or an ad libitum diet (AL). 2-4 replicates of each experimental condition were used in the analysis.
Project description:The SIRT1 deacetylase is one of the best-studied potential mediators of some of the anti-aging effects of calorie restriction (CR); but its role in CR-dependent lifespan extension has not been demonstrated. We previously found that mice lacking both copies of SIRT1 displayed a shorter median lifespan than wild type mice on an ad libitum diet. Here we report that median lifespan extension in CR heterozygote SIRT1+/- mice was identical (51%) to that observed in wild type mice but SIRT1+/- mice displayed a higher frequency of some certain pathologies. Although larger studies in different genetic backgrounds are necessary , these results provide strong initial evidence for the requirement of SIRT1 for the anti-aging effects of CR, but suggest that its high expression is not required for CR-induced lifespan extension. Key words: SIRT1, caloric restriction, lifespan, anti-aging
Project description:The prevention or delay of the onset of age-related diseases prolongs survival and improves quality of life while reducing the burden on the health care system. Activation of sirtuin 1 (SIRT1), an NAD+ deacetylase, improves metabolism and confers protection against physiological and cognitive disturbances in old age. SRT1720 is a specific SIRT1 activator that has health and lifespan benefits in adult mice fed a highfat diet. We found extension in lifespan, delayed onset of age-related metabolic diseases, and improved general health in mice fed a standard diet after SRT1720 supplementation. Inhibition of pro-inflammatory gene expression both in the liver and muscle of SRT1720-treated animals was noted. SRT1720 lowered phosphorylation of NF-κB pathway regulators in vitro only when SIRT1 was functionally present. Combined with our previous work, the current study further supports the beneficial effects of SRT1720 on health across the lifespan in mice.
Project description:Caloric restriction (CR) enhances the function of adult stem cells and significantly extends the lifespan of many organisms including rodents. CR increases the expression of Period genes in several tissues in mice, and the circadian machinery is strongly influenced by feeding and metabolic pathways. Importantly, Bmal1-deficient mice, or Period/Timeless-deficient Drosophila are refractory to the lifespan extension induced by CR. We therefore studied whether CR could prevent the ageing related circadian reprogramming we had observed in epidermal SCs.
Project description:Caloric restriction (CR) enhances the function of adult stem cells and significantly extends the lifespan of many organisms including rodents. CR increases the expression of Period genes in several tissues in mice, and the circadian machinery is strongly influenced by feeding and metabolic pathways. Importantly, Bmal1-deficient mice, or Period/Timeless-deficient Drosophila are refractory to the lifespan extension induced by CR. We therefore studied whether CR could prevent the ageing related circadian reprogramming we had observed in muscle SCs.
Project description:Resveratrol (3,5,4'-trihydroxystilbene) extends the lifespan of diverse species including yeast, worms, and flies. In these organisms, lifespan extension is dependent on Sir2, a conserved deacetylase proposed to underlie the beneficial effects of caloric restriction (CR). Here we show that resveratrol shifts the physiology of middle-aged mice on a high-calorie diet towards that of mice on a standard diet and significantly increases their survival. Resveratrol produces changes associated with longer lifespan including increased insulin sensitivity, reduced IGF-1, increased AMPK and PGC-1α activity, increased mitochondrial number, and improved motor function. Parametric analysis of gene set enrichment (PAGE) revealed that resveratrol opposed the effects of the high-calorie diet in 144 out of 153 significantly altered pathways. These data show that improving general health in mammals using small molecules is an attainable goal and point to new approaches for treating obesity-related disorders and diseases of ageing. Keywords: Drug treatment
Project description:Resveratrol (3,5,4'-trihydroxystilbene) extends the lifespan of diverse species including yeast, worms, and flies. In these organisms, lifespan extension is dependent on Sir2, a conserved deacetylase proposed to underlie the beneficial effects of caloric restriction (CR). Here we show that resveratrol shifts the physiology of middle-aged mice on a high-calorie diet towards that of mice on a standard diet and significantly increases their survival. Resveratrol produces changes associated with longer lifespan including increased insulin sensitivity, reduced IGF-1, increased AMPK and PGC-1α activity, increased mitochondrial number, and improved motor function. Parametric analysis of gene set enrichment (PAGE) revealed that resveratrol opposed the effects of the high-calorie diet in 144 out of 153 significantly altered pathways. These data show that improving general health in mammals using small molecules is an attainable goal and point to new approaches for treating obesity-related disorders and diseases of ageing. Experiment Overall Design: One-year-old male C57BL/6 mice were maintained on AIN-93G standard diet (SD), AIN-93G modified to provide 60% of calories from fat (HC), or HC diet with the addition of 0.04% resveratrol (HCR). Total RNA from the livers of 5 replicate animals from the first 2 groups and 4 from the 3rd group were labeled and hybridized to Agilent 44K whole genome microarrays.
Project description:The biguanide metformin improves health and survival in male mice; however, it is unclear whether metformin will confer health and lifespan benefits to mice when started late in life. Two year-old mice fed on standard chow were treated with 1% metformin every-other week (EOW) or two consecutive weeks per month (2WM). EOW mice displayed improvements in healthspan reminiscent of mice on caloric restriction. The age-associated histopathological changes in liver and kidney were significantly reduced in EOW compared to 2WM or control mice. Some of the affected gene transcripts and metabolites were found to be risk predictors of metabolic disorder. Neither EOW nor 2WM mice exhibited extension in mean or maximum lifespan compared with control animals. Thus, metformin supplementation had a strong impact on reversing some of the deleterious effects of aging and resulted in an improvement of health in old male mice in the absence of an extension of lifespan.
Project description:Cockayne syndrome (CS) is an accelerated aging disorder characterized by progressive neurodegeneration caused by mutations in the genes encoding the DNA repair proteins CSA or CSB. Csbm/m mice were given a high-fat, caloric-restricted or resveratrol-supplemented diet. The high-fat diet rescued the phenotype of Csbm/m mice at the metabolic, transcriptomic and behavioral levels. Additional analysis suggests that the premature aging seen in CS mice, nematodes and human cells results from aberrant PARP activation due to deficient DNA repair leading to decreased SIRT1 activity and mitochondrial dysfunction. Notably, β-hydroxybutyrate levels are increased by the high-fat diet; and β-hydroxybutyrate, PARP inhibition, or NAD+ supplementation can activate SIRT1 and rescue CS-associated phenotypes. Mechanistically, CSB is able to displace activated PARP1 from damaged DNA to limit its activity. This study connects two emerging longevity metabolites, β-hydroxybutyrate and NAD+, through the deacetylase SIRT1 and suggests possible interventions for CS.
Project description:This dataset consists of hepatic gene expression profiles of mice subjected to 8 different lifespan-extending interventions, together with the corresponding age-, sex- and strain-matched littermate controls: caloric restriction (CR), methionine restriction (MR), growth hormone receptor knockout (GHRKO), Snell dwarf mice (Pit1 -/-), rapamycin, acarbose, 17-alpha-estradiol (17aE2) and Protandim. Both sexes and different age groups are presented within dataset. Using this data, we identified general and specific gene expression patterns associated with lifespan extension. We detected a feminization effect associated with growth hormone regulation and diminution of sex-related differences in response to many interventions at transcriptome and metabolome levels. Combining the dataset with publicly available resources, we found that many interventions exhibited similar transcriptome changes, whereas some, including rapamycin, showed distinct patterns. We identified common hepatic signatures of lifespan extension, e.g. upregulation of oxidative phosphorylation and NRF2-regulated enzymes, and found that many perturbed pathways are shared across tissues. Moreover, the response of genes related to glucose metabolism and immune function represented both qualitative and quantitative associations with longevity. Finally, we used the detected longevity signatures to identify new candidates for lifespan extension and built GENtervention, a tool that visualizes associations of gene expression responses with lifespan extension.