Mus musculus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA214888 | ENA |
REPOSITORIES: ENA
Similar Datasets
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: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:We evaluated the effects of NAMPT (nicotinamide phosphoribosyltransferase) knockout on transcriptome in brown adipose tissue (BAT) by analyzing BAT obtained from control (Nampt-flox/flox, F1-F4) and adipocyte-specific Nampt knockout (ANKO, A1-A4) mice.
2019-11-14 | GSE137149 | GEO
Project description:Type 2 diabetes (T2D) has become an epidemic in our modern lifestyle, likely due to calorie-rich diets overwhelming our adaptive metabolic pathways. One such pathway is mediated by nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in mammalian NAD+ biosynthesis, and the NAD+-dependent protein deacetylase SIRT1. Here we show that NAMPT-mediated NAD+ biosynthesis is severely compromised in metabolic organs by high-fat diet (HFD). Strikingly, nicotinamide mononucleotide (NMN), a product of the NAMPT reaction and a key NAD+ intermediate, ameliorates glucose intolerance by restoring NAD+ levels in HFD-induced T2D mice. NMN also enhances hepatic insulin sensitivity and restores gene expression related to oxidative stress, inflammatory response, and circadian rhythm, partly through SIRT1 activation. Furthermore, NAD+ and NAMPT levels show significant decreases in multiple organs during aging, and NMN improves glucose intolerance and lipid profiles in age-induced T2D mice. These findings provide critical insights into a novel intervention against diet- and age-induced T2D. 4 regular chow fed mice (RC1-4) vs 4 high-fat diet fed (HFD) (HFD1a-4a) mice were analyzed on one chip (Chip-A). 4 HFD mice (HFD1b-4b) vs 4 HFD-NMN treated mice (NMN1-4) were examined on the other chip (Chip-B).
2011-12-05 | E-GEOD-31647 | biostudies-arrayexpress
Project description:Through integration of whole genome CRISPR screening and pan-cancer genetic dependency mapping, we identified nicotinamide phosphoribosyltransferase (NAMPT) and nicotinamide nucleotide adenylyltransferase 1 (NMNAT1) as acute myeloid leukemia (AML) dependencies governing NAD+ biosynthesis. While both NAMPT and NMNAT1 were required for AML, we found that the presence of NAD+ precursors bypassed the dependence of AML on NAMPT, but not NMNAT1, pointing to NMNAT1 as a gatekeeper of NAD+ biosynthesis. We provide evidence that reduced nuclear NAD+ upon deletion of NMNAT1 activated p53, which is due to attenuated deacetylation by SIRT6/7 in AML cells. Our findings reveal that NAD+ is a critical metabolic foundation for AML, and NMNAT1 is a novel therapeutic target for this disease.
2021-07-28 | GSE171565 | GEO
Project description:We investigated the plasma and liver proteome changes in liver fibrosis in mice induced by hepatocyte-specific knockout of nicotinamide phosphoribosyltransferase (Nampt) upon a low-methionine, choline-free 60% high-fat (MCD) diet at multiple time points. We also investigated whether supplementation with nicotinamide riboside could alleviate liver injury and how the liver proteome changes upon NR supplementation.
2021-11-04 | PXD017170 | Pride
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:Nicotinamide phosphoribosyltransferase (NAMPT) functions in NAD synthesis, apoptosis, and inflammation. Dysregulation of NAMPT has been associated with several inflammatory diseases, including rheumatoid arthritis (RA). The purpose of this study was to investigate NAMPT’s role in arthritis using mouse and cellular models. Collagen-induced arthritis (CIA) in DBA/1J Nampt+/- mice was evaluated by ELISA, micro-CT and RNA-sequencing (RNA-seq). In vitro Nampt loss-of-function and gain-of-function studies on osteoclastogenesis were examined by TRAP staining, nascent RNA capture, luciferase reporter assays, and ChIP-PCR. Nampt-deficient mice presented with suppressed inflammatory bone destruction and disease progression in a CIA mouse model. Nampt expression was required for the epigenetic regulation of the Nfatc1 promoter and osteoclastogenesis. Finally, RNA-seq identified 690 differentially expressed genes in whole ankle joints which associated (P<0.05) with Nampt expression and CIA. Selected target was validated by RT-PCR or functional characterization. We have provided evidence that NAMPT functions as a genetic risk factor and a potential therapeutic target to RA.
2019-01-31 | GSE121793 | GEO
Project description:Type 2 diabetes (T2D) has become an epidemic in our modern lifestyle, likely due to calorie-rich diets overwhelming our adaptive metabolic pathways. One such pathway is mediated by nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in mammalian NAD+ biosynthesis, and the NAD+-dependent protein deacetylase SIRT1. Here we show that NAMPT-mediated NAD+ biosynthesis is severely compromised in metabolic organs by high-fat diet (HFD). Strikingly, nicotinamide mononucleotide (NMN), a product of the NAMPT reaction and a key NAD+ intermediate, ameliorates glucose intolerance by restoring NAD+ levels in HFD-induced T2D mice. NMN also enhances hepatic insulin sensitivity and restores gene expression related to oxidative stress, inflammatory response, and circadian rhythm, partly through SIRT1 activation. Furthermore, NAD+ and NAMPT levels show significant decreases in multiple organs during aging, and NMN improves glucose intolerance and lipid profiles in age-induced T2D mice. These findings provide critical insights into a novel intervention against diet- and age-induced T2D.
2011-12-05 | GSE31647 | GEO
Project description:Drugs targeting mutant oncogenes are effective, even though resistance rapidly develops. This complex picture includes acquired intrinsic tumor and tumor microenvironmental -mediated mechanisms. Here we showed that melanoma cells resistant to BRAF inhibitors (BRAFi) overexpressed the rate limiting enzymes involved in nicotinamide (NAM) metabolism nicotinamide phosphoribosyltransferase (NAMPT) and nicotinamide N-methyltransferase (NNMT). Importantly, NAMPT and NNMT are released by these cells, both in the free-form or loaded in extracellular vesicles (EVs). NAMPT is emerging as mediator of BRAFi resistance in melanoma, but to date mainly associated with its role as main NAD-biosynthetic enzyme. It had been previously identified as soluble factor, but never in EVs released from melanoma cells, which highlights an impact on the tumor microenvironment (TME). NNMT was revealed increased in melanoma compared to benign nevi, however we showed for the first time its overexpression in resistant cells at intracellular and extracellular levels (present in secretome and in EVs). NNMT increased in BRAF-mutated patients linking its expression with the BRAF oncogenic signaling and correlates positively with pro-inflammatory signaling, immune cell migration and chemokine-mediated signaling pathways opening to a future deeper exploration of its functional role. Lastly, we proposed a tetrameric NNMT:TLR4 binding model offering a plausible structural and mechanistic basis for their association. Overall, the identification of NAMPT and, surprisingly also NNMT, included in EVs and abundantly released from resistant melanoma cells supports the impact of these moonlighting proteins involved in nicotinamide metabolism as mediators of BRAF/MEK inhibitors resistance with tumor intrinsic and potentially tumor microenvironment-mediated mechanisms. Interfering with nicotinamide metabolism could be a valid strategy to counteract drug resistance acting on the multifactorial tumor-host interactions.
2025-07-28 | PXD063060 | Pride