Role of SIRT1 in NAMPT-induced liver gene expression
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ABSTRACT:
PROVIDER: PRJNA764444 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:We tested they hypothesis that hepatocyte SIRT1 mediates transcriptomic changes induced by hepatocyte-specific NAMPT overexpression
2021-09-21 | GSE184394 | GEO
Project description:Role of hepatocyte NAMPT in fasting-induced liver gene expression
| PRJNA764442 | ENA
Project description:Neural stem/progenitor cell (NSPC) proliferation and self-renewal, as well as insult-induced differentiation, decrease markedly with age, but the molecular mechanisms responsible for these declines remain unclear. Here we show that levels of NAD+ and nicotinamide phosphoribosyltransferase (Nampt), the rate-limiting enzyme in mammalian NAD+ biosynthesis, decrease with age in the hippocampus. Ablation of Nampt in adult NSPCs reduced their pool and proliferation in vivo. The decrease in the NSPC pool during aging can be rescued by enhancing hippocampal NAD+ levels. Nampt is the main source of NSPC NAD+ levels and required for G1/S progression of the NSPC cell cycle. Nampt is also critical for oligodendrocytic lineage fate decisions through a mechanism mediated redundantly by Sirt1 and Sirt2. Ablation of Nampt in the adult NSPCs in vivo reduced NSPC-mediated oligodendrogenesis upon injury. These phenotypes recapitulate defects in NSPCs during aging, implicating Nampt-mediated NAD+ biosynthesis as a mediator of these age-associated functional declines. Total RNA obtained from neurospheres derived from postnatal hippocampi subjected to 48 hours in vitro of incubation with Nampt-specific inhibitor FK866 (10 nM, 4 samples) or vehicle (DMSO, 1:1000, 4 samples).
2014-05-08 | E-GEOD-49784 | biostudies-arrayexpress
Project description:We tested they hypothesis that hepatocyte NAMPT mediates transcriptomic changes induced by fasting
2021-09-21 | GSE184395 | GEO
Project description:The purpose of this study is to investigate the role of SIRT1 in high-fat diet-induced liver steatosis and insulin resistance. SIRT1 is a nuclear enzyme that could remove an acetyl-group from target proteins by using NAD as co-substrate. Homologs of this protein in yeast and the roundworm C. elegans are able to delay the aging process in response to nutrients. However, the molecular mechanism by which SIRT1 sense the environment to mediate this response are poorly understood. We have shown that when chronically fed with a 40%-fat diet, SIRT1 heterozygous animals gain significantly more weight compared to wild type littermates. They are also hyperinsulimia, more insulin-resistant, and accumulate more lipids in liver. Interestingly, these animals also show signs of premature aging, such as an early appearance of gray fur, defective motor activity, and decreased fertility. In this microarray study, we analyzed the gene expression profiles in the liver of WT low-fat diet, Het low-fat diet, WT high-fat diet, and Het high-fat diet using Agilent Whole Genome Mouse 4x44 multiplex format oligo arrays following the Agilent-1-color microarray-based gene expression analysis protocol. This microarray analysis concluded that SIRT1 Het mice reponsed to the high-fat diet differently from the WT control mice. Liver total RNAs from SIRT1 WT and Het mice that were fed with either a low-fat diet or a high-fat diet for 34 weeks were used for a microarray gene expression study. Three biological replicates for each group were used.
2012-07-31 | E-GEOD-39778 | biostudies-arrayexpress
Project description:The purpose of this study is to investigate the role of SIRT1 in high-fat diet-induced liver steatosis and insulin resistance. SIRT1 is a nuclear enzyme that could remove an acetyl-group from target proteins by using NAD as co-substrate. Homologs of this protein in yeast and the roundworm C. elegans are able to delay the aging process in response to nutrients. However, the molecular mechanism by which SIRT1 sense the environment to mediate this response are poorly understood. We have shown that when chronically fed with a 40%-fat diet, SIRT1 heterozygous animals gain significantly more weight compared to wild type littermates. They are also hyperinsulimia, more insulin-resistant, and accumulate more lipids in liver. Interestingly, these animals also show signs of premature aging, such as an early appearance of gray fur, defective motor activity, and decreased fertility. In this microarray study, we analyzed the gene expression profiles in the liver of WT low-fat diet, Het low-fat diet, WT high-fat diet, and Het high-fat diet using Agilent Whole Genome Mouse 4x44 multiplex format oligo arrays following the Agilent-1-color microarray-based gene expression analysis protocol. This microarray analysis concluded that SIRT1 Het mice reponsed to the high-fat diet differently from the WT control mice.
2012-08-01 | GSE39778 | GEO
Project description:Neural stem/progenitor cell (NSPC) proliferation and self-renewal, as well as insult-induced differentiation, decrease markedly with age, but the molecular mechanisms responsible for these declines remain unclear. Here we show that levels of NAD+ and nicotinamide phosphoribosyltransferase (Nampt), the rate-limiting enzyme in mammalian NAD+ biosynthesis, decrease with age in the hippocampus. Ablation of Nampt in adult NSPCs reduced their pool and proliferation in vivo. The decrease in the NSPC pool during aging can be rescued by enhancing hippocampal NAD+ levels. Nampt is the main source of NSPC NAD+ levels and required for G1/S progression of the NSPC cell cycle. Nampt is also critical for oligodendrocytic lineage fate decisions through a mechanism mediated redundantly by Sirt1 and Sirt2. Ablation of Nampt in the adult NSPCs in vivo reduced NSPC-mediated oligodendrogenesis upon injury. These phenotypes recapitulate defects in NSPCs during aging, implicating Nampt-mediated NAD+ biosynthesis as a mediator of these age-associated functional declines.
2014-05-08 | GSE49784 | GEO
Project description:Acetaminophen overdose is the most common cause of acute liver injury (ALI) or acute liver failure in the USA. Its pathogenetic mechanisms are incompletely understood. Additional studies are warranted to identify new genetic risk factors for more mechanistic insights and new therapeutic target discoveries. The objective of this study was to explore the role and mechanisms of nicotinamide phosphoribosyltransferase (NAMPT) in acetaminophen-induced ALI. C57BL/6 Nampt gene wild type (Nampt+/+)-, heterozygous knockout (Nampt+/-)-, and overexpression (NamptOE)-mice were treated with overdose of acetaminophen, followed by histological, biochemical, and transcriptomic evaluation of liver injury. The mechanism of Nampt in acetaminophen -induced hepatocytic toxicity was also explored in cultured primary hepatocytes. Three lines of evidence have convergently demonstrated that acetaminophen overdose triggers the most severe oxidative stress and necrosis, and the highest expression of key necrosis driving genes in Nampt+/- mice, while the effects in NamptOE mice were least severe relative to Nampt+/+ mice. These findings support that NAMPT protects against acetaminophen induced ALI.
2018-04-03 | GSE110787 | GEO
Project description:Role of NAMPT in liver gene expression in diabetic mice
| PRJNA764907 | ENA
Project description:Hypothesis is that NAMPT overexpression alters liver transcriptomics in genetically diabetic, obese db/db mice. We treated db/db mice n = 4 with adenovirus encoding GFP or NAMPT by tail-vein delivery.
2022-08-01 | E-MTAB-10984 | biostudies-arrayexpress