Ontology highlight
ABSTRACT:
PROVIDER: PRJNA556932 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Exogenous pyruvate represses histone gene expression to inhibit cancer cell proliferation via the NAMPT-NAD + -SIRT1 pathway
| PRJNA560223 | ENA
Project description:Pyruvate is a glycolytic metabolite used for energy production and macromolecule biosynthesis. However, little is known about its potential functions in tumorigenesis. Here,we report that exogenous pyruvate inhibits the proliferation of different types of cancer cells. This inhibitory effect of pyruvate on cell growth is attributed to its function as a signal molecule to repress histone gene expression, which leads to less compact chromatin structure and misregulation of genome-wide gene expression. Pyruvate represses histone gene expression by inducing the expression of NAD + biosynthesis enzyme, nicotinamide phosphoribosyltransferase (NAMPT), which increases NAD + levels and NAD + /NADH ratio. This increase activates the histone deacetylase activity of SIRT1. Chromatin immunoprecipitation analysis indicates that pyruvate enhances SIRT1 binding at histone gene promoters where it reduces histone acetylation. Although pyruvate delays cell entry into S phase, pyruvate represses histone gene expression independent of cell cycle progression. Moreover, we find that administration of pyruvate significantly reduces histone expression and retards tumor growth in xenograft mice without significant side effects. Using tissues from cervical cancer patients, we find intracellular pyruvate concentrations inversely correlate with histone protein levels. Together, we uncover a previously unknown function of pyruvate in histone gene expression and characterize pyruvate as a potential anti-cancer agent.
2019-12-05 | GSE135831 | 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. 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: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:In mammals, nicotinamide phosphoribosyltransferase (NAMPT) and nicotinamide mononucleotide adenylyltransferase 1 (NMNAT-1) constitute a nuclear NAD+ salvage pathway, regulating cellular functions of the NAD+-dependent deacetylase SIRT1. However, little is known about the molecular mechanisms by which NAD+ biosynthesis controls gene transcription in the nucleus. In this study, we show that stable knockdown of NAMPT or NMNAT-1 in MCF-7 breast cancer cells significantly reduced total cellular NAD+ levels. Expression microarray analyses demonstrate that both enzymes have broad and overlapping functions in gene regulation. SIRT1 is a key mediator of NAMPT- and NMNAT-1-dependent gene regulation, and is found at promoters of many of the target genes. Furthermore, SIRT1 deacetylase activity at these promoters is regulated by NAMPT and NMNAT-1. Most significantly, NMNAT-1 interacts with SIRT1 and is recruited to target gene promoters by SIRT1. Our results reveal an unexpected mechanism for the direct control of SIRT1 deacetylase activity at target gene promoters by NMNAT-1. Interactions between NMNAT-1 and SIRT1 at gene promoters may provide a platform for integration of multiple signaling pathways that regulate transcription. This SuperSeries is composed of the SubSeries listed below.
2009-05-28 | GSE13577 | 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: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:NAD is an obligate co-factor for the catabolism of metabolic fuels in all cell types. However, the availability of NAD in several tissues can become limited during genotoxic stress and the course of natural aging. The point at which NAD restriction imposes functional limitations on tissue physiology remains unknown. We examined this question in murine skeletal muscle by specifically depleting Nampt, an essential enzyme in the NAD salvage pathway. Knockout mice exhibited a dramatic 85% decline in intramuscular NAD content, accompanied by fiber degeneration and progressive loss of both muscle strength and treadmill endurance. Administration of the NAD precursor nicotinamide riboside rapidly ameliorated functional deficits and restored muscle mass, despite having only a modest effect on the intramuscular NAD pool. Additionally, lifelong overexpression of Nampt preserved muscle NAD levels and exercise capacity in aged mice, supporting a critical role for tissue-autonomous NAD homeostasis in maintaining muscle mass and function. Messenger RNA was isolated from quadriceps muscle of mice from three different age groups and three different genotypes. Wildtype mice were aged 4, 7, and 24 months. Mice deficient for Nampt in skeletal muscle (mNKO) were aged 7 months. Mice overexpressing Nampt in skeletal muscle were aged 4 and 24 months.
2016-07-22 | E-GEOD-74570 | biostudies-arrayexpress
Project description:Chondrosarcomas represent the second most common primary bone malignancy. Despite the vulnerability of chondrosarcoma cells to nicotinamide adenine dinucleotide (NAD+) depletion, targeting the NAD+ synthesis pathway remains challenging due to broad implications in biological processes. Here, we establish SIRT1 as a central mediator reinforcing the dependency of chondrosarcoma cells on NAD+ metabolism via HIF-2α-mediated transcriptional reprogramming. SIRT1 knockdown abolishes aggressive phenotypes of chondrosarcomas in orthotopically transplanted tumors in mice. Chondrosarcoma cells thrive under glucose starvation by accumulating NAD+ and subsequently activating the SIRT1–HIF-2α axis. Decoupling this link via SIRT1 inhibition unleashes apoptosis and suppresses tumor progression in conjunction with chemotherapy. Unsupervised clustering analysis identifies a high-risk chondrosarcoma patient subgroup characterized by the upregulation of NAD+ biosynthesis genes. Finally, SIRT1 inhibition abolishes HIF-2α transcriptional activity and sensitizes chondrosarcoma cells to doxorubicin-induced cytotoxicity, irrespective of underlying pathways to accumulate intracellular NAD+. We provide system-level guidelines to develop therapeutic strategies for chondrosarcomas.
2023-12-01 | GSE248490 | GEO
Project description:NAMPT is an enzyme in the mammalian NAD+ salvage pathway. Expression microarray analysis was used to study the effect of NAMPT knockdown on gene expression in MCF-7 breast cancer cells. Experiment Overall Design: Stable knockdown of NAMPT was achieved using a retroviral shRNA construct. An shRNA directed against Luciferase was used to generate the Luc control cells. Three independent biological replicates with matching Luc controls were analyzed using Affymetrix U133 A2.0 microarrays.
2009-06-08 | E-GEOD-13449 | biostudies-arrayexpress