Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Vitamin B2 enables PPARa regulation of fasting glucose availability

ABSTRACT: Flavin adenine dinucleotide (FAD) mediates oxidation-reduction reactions required for cellular energy demands. Fatty acid oxidation (FAO) disorders caused by flavoprotein mutations and FAD depletion disrupt energy balance and glucose production during fasting. These FAO disorders are difficult to manage clinically, and their biochemical pathogenesis is poorly understood. Here, we identify a mechanistic connection between FAD levels and hepatic glucose production. Depleting the FAD pool in mice with a vitamin B2 deficient diet (B2D) resulted in phenotypes associated with organic acidemia phenotypes, including reduced body weight and whole-body fat oxidation rates coupled with hypoglycemia. Integrated discovery approaches revealed that B2D broadly tempered fasting activation of target genes for the nuclear receptor PPARa, including those required for gluconeogenesis. Consistent with this, Ppara knockout depleted liver FAD levels and worsened B2D hepatic glucose production. Treatment with the PPARa agonist fenofibrate overcame B2D phenotypes and rescued glucose availability and fatty liver signatures through activation of the integrated stress response and refilling anaplerotic amino acid substrates for glucose production. We conclude that PPARa governs metabolic responses to FAD availability and suggest pharmacologic activation as a strategy for treating disorders of riboflavin and FAD deficiency.

ORGANISM(S): Mus musculus

PROVIDER: GSE206200 | GEO | 2022/06/18

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

Diet-induced circadian enhancer remodeling synchronizes opposing hepatic lipid metabolic processes

Project description:Overnutrition disrupts circadian rhythms leading to dysregulated metabolism by mechanisms that are not well understood. Here we show that diet-induced obesity (DIO) causes massive remodeling of circadian enhancer activity and gene transcription in mouse liver. Remarkably, DIO triggers synchronous, high amplitude circadian rhythms of both fatty acid (FA) synthesis and oxidation. This gain of circadian rhythmicity in lipid metabolic pathways that oppose each other emphasizes the importance of balance and flux in normal hepatic lipid metabolism. DIO-promoted rhythmicity of Sterol Regulatory Element-Binding Protein (SREBP) activation, which was required not only for the induction of FA synthesis but also, surprisingly, for FA oxidation (FAO). DIO also brought about a high amplitude circadian rhythm of peroxisome proliferated receptor a (PPARa), which was required for FAO. Provision of a pharmacological ligand for PPARa abrogated the requirement of SREBP for FA oxidation (but not FA synthesis), suggesting that SREBP indirectly controls FA oxidation via production of an endogenous PPARa ligand. Moreover, the high amplitude circadian rhythm of PPARa imparts time-of-day-dependent responsiveness to lipid-lowering drugs. Thus, acquisition of rhythmicity for the non-core clock components PPARa and SREBP1 remodels metabolic gene transcription in response to a challenging nutritive environment and enables a chronopharmacological approach to metabolic disorders.

2018-07-26 | GSE108878 | GEO

Vitamin B2 enables PPARa regulation of fasting glucose availability

Project description:Vitamin B2 enables PPARa regulation of fasting glucose availability

| PRJNA849596 | ENA

Endogenous renal adiponectin drives gluconeogenesis through enhancing pyruvate and fatty acid utilization

Project description:Adiponectin is an important secretory protein, primarily produced in adipose tissue. However, low but detectable expression of adiponectin can be observed in cell types beyond adipocytes, particularly in kidney tubular cells, but its local renal role is unknown. We assessed the role of renal adiponectin by utilizing male doxycycline inducible kidney tubular cell-specific adiponectin overexpression or knockout mice. Kidney-specific adiponectin overexpression induces a doubling of phosphoenolpyruvate carboxylase expression and enhanced pyruvate-mediated glucose production, tricarboxylic acid cycle intermediates and an upregulation of fatty acid oxidation (FAO). The inhibition of FAO reduces the adiponectin-induced enhancement of glucose production, highlighting the role of FAO in the induction of renal gluconeogenesis. In contrast, kidney-specific adiponectin deleted mice exhibit enhanced glucose tolerance as well as a lower utilization and greater accumulation of lipid species. In summary, renal adiponectin is a potent inducer of gluconeogenesis by driving enhanced FAO in the kidney and underline the important systemic role of renal gluconeogenesis.

2023-09-20 | GSE242095 | GEO

Effect of p16 deficiency on gene expression in primary hepatocytes

Project description:*Objectives:* In addition to their well-known role in the control of cellular proliferation and cancer, cell cycle regulators are increasingly identified as important metabolic modulators. Genome wide association studies identified SNPs near the cell cycle regulator CDKN2A/p16INK4a (p16) as strongly associated with risk of developing type 2 diabetes (T2D). T2D is associated with numerous perturbations of hepatic lipid and glucose metabolism. We have recently shown that p16 controls fasting-induced hepatic gluconeogenesis in mice. However, whether p16 may also affect hepatic lipid homeostasis is unknown. *Results:* In primary hepatocytes, p16-deficiency was associated with elevated expression of genes involved in fatty acid catabolism and enhanced activation of PPAR. This led to increased mitochondrial fatty acid oxidation (FAO) through a mechanism requiring the catalytic AMPK 2 subunit and SIRT1. By contrast, *p16* overexpression was associated with triglyceride accumulation and increased lipid droplet numbers *in vitro*, and decreased ketogenesis and hepatic mitochondrial activity *in vivo*. Gene expression analysis of human liver samples revealed a negative correlation between *CDKN2A* expression and *PPARA* and its target genes, suggesting a potential association between hepatic p16 expression and FAO in obese humans. *Conclusions:* Our findings demonstrate that p16 plays a key role in hepatic lipid metabolism and may thus contribute to the development of metabolic diseases.

2020-10-09 | GSE134625 | GEO

FBP1 acts as a protein phosphatase to dephosphorylate histone H3

Project description:We report nuclear FBP1 interacts with PPARa and binds to the promoter regions of PPARa-mediated b-oxidation genes. S170-phosphorylated FBP1 with an altered catalytic domain structure functions as a protein phosphatase that dephosphorylates histone H3 at T11 and suppresses PPARa-mediated gene expression. Chromatin immunoprecipitation DNA-sequencing (ChIP-seq) for FBP1 and PPARa with glucose deprivation in L02 cells.

2022-10-04 | GSE207844 | GEO

Quiescent endothelial cells upregulate fatty acid β-oxidation for vasculoprotection via redox homeostasis

Project description:Little is known about metabolic changes accompanying endothelial cell (EC) quiescence. Nonetheless, when dysfunctional, quiescent ECs (QECs) contribute to multiple cardiovascular diseases. ECs need fatty acid β-oxidation (FAO) for proliferation. Surprisingly, we now report that QECs are not hypo-metabolic, but upregulate FAO >3-fold higher than proliferating ECs (PECs), not to support biomass or energy production, but to sustain the TCA cycle for redox homeostasis through NADPH production. Hence, inhibition of FAO-controlling CPT1A promotes EC dysfunction (anti-fibrinolysis, leukocyte infiltration, barrier disruption) by increasing oxidative stress in CPT1AΔEC mice with endothelial CPT1A loss. Mechanistically, Notch1 orchestrates the use of FAO for redox balance in QECs. Supplementation of acetate (metabolized to acetyl-CoA) induces vasculoprotection against oxidative stress and EC dysfunction in CPT1AΔEC mice, possibly creating therapeutic opportunities. Thus, ECs use FAO for vasculoprotection against their high oxygen (oxidative stress-prone) milieu, and for different metabolic purposes dependent on their proliferation versus quiescence status.

2018-09-12 | E-MTAB-6595 | biostudies-arrayexpress

Global hepatic gene expression data from PPARa liver KO, PPARa liver WT, PPARaKO and WT male mice fed ad libitum, fasted for 24 hours and re-fed

Project description:If the function of the nuclear receptor PPARa is well-known during a prolongated fasting, its hepatic biological function during feeding and refeeding conditions still needs to be investigated. Moreover, in vivo data collected so far on PPARa function during fasting were obtained using the total Ppara KO transgenic mouse model. To identify genes whose expression is under the strict dependence of hepatic PPARa activity, we generated a new mouse strain of PPARa-specific deletion in hepatocyte (albumin-Cre+/- Pparaflox/flox or LKO) and we compared them to total Ppara KO (KO), wild-type (WT) and liver WT (albumin-Cre-/- Pparaflox/flox or LWT) mice under three nutritional challenges. We used microarrays to detail the global programme of gene expression in liver of Ppara LKO, LWT, Ppara KO and WT male mice fed ad libitum, fasted for 24 hours and refed. There are 52 liver samples, each from an individual mouse. The samples are from Ppara liver KO (LKO), Ppara KO (KO), wild-type (WT) and liver WT (LWT) male mice of 8 week-old from the same genetic background (C57Bl/6J) fed ad libitum, fasted for 24 hours, fasted for 24 hours and then refed 24 hours more with glucose added in water (200g/l). In fed condition (Fed), n= 3 mice for LKO, LWT genotypes, n= 5 for KO and n= 4 fot WT; in fasting condition (Fas), n=5 for LKO, LWT and WT genotypes and n= 3 for KO; in refeeding condition (Ref), n= 5 for LKO, KO and WT genotypes and n= 4 for LWT. All mice were sacrified at ZT14.

2016-02-20 | E-GEOD-73299 | biostudies-arrayexpress

A mitochondrial long-chain fatty acid oxidation defect leads to uncharged tRNA accumulation and activation of the integrated stress response in the mouse heart

Project description:The heart relies mainly on mitochondrial fatty acid beta-oxidation (FAO) for its high energy requirements. Cardiomyopathy and arrhythmias can be severe complications in patients with inherited defects in mitochondrial long-chain FAO, reinforcing the importance of FAO for cardiac health. However, the pathophysiological mechanisms that underlie the cardiac abnormalities in long-chain FAO disorders remain largely unknown. Here, we investigated the cardiac transcriptional adaptations to the FAO defect in the long-chain acyl-CoA dehydrogenase (LCAD) knockout (KO) mouse. We found a prominent activation of the integrated stress response (ISR) mediated by the eIF2a/ATF4 axis in both fed and fasted states, accompanied by a reduction in cardiac protein synthesis during a short period of food withdrawal. Notably, we found an accumulation of uncharged tRNAs in LCAD KO hearts, consistent with a reduced availability of cardiac amino acids, in particular, glutamine. We replicated the activation of the cardiac ISR in hearts of mice with a muscle-specific deletion of carnitine palmitoyltransferase 2 deletion (Cpt2M-/-). Our results show that perturbations in amino acid metabolism caused by long-chain FAO deficiency impact cardiac metabolic signaling, in particular the ISR, and may play a role in the associated cardiac pathology.

2021-06-11 | GSE176553 | GEO

Chronic hyperglycemia impairs metabolic switching of human myotubes

Project description:Skeletal muscle of insulin resistant individuals is characterized by lower fasting lipid oxidation and reduced ability to switch between lipid and glucose oxidation. The purpose of the present study was to examine if impaired metabolic switching could be induced by chronic hyperglycemia. Human myotubes were treated with or without chronic hyperglycemia (HG) (20 mmol/l glucose for 4 days), and the metabolism of [14C]oleic acid (OA) and [14C]glucose was studied. Acute glucose (5mmol/l) suppressed OA oxidation by 50% in normoglycemic (NG) (5.5 mmol/l glucose) cells. Myotubes exposed to chronic hyperglycemia showed a significantly reduced OA uptake and oxidation to CO2, whereas acid-soluble metabolites were increased. Glucose suppressibility, the ability of acute glucose to suppress lipid oxidation, was significantly reduced to 21%, while adaptability, the capacity to increase lipid oxidation with increasing fatty acid availability, was unaffected. Glucose uptake and oxidation was significantly reduced by about 40%. Substrate oxidation in presence of mitochondrial uncouplers showed that net and maximal oxidative capacities were significantly reduced after hyperglycemia, and the concentration of ATP was reduced by 25%. However, none of the measured mitochondrial genes were downregulated nor was mitochondrial content. Microarray showed that no genes were significantly regulated by chronic hyperglycemia. Addition of chronic lactate reduced both glucose and OA oxidation to the same extent as hyperglycemia, and this effect was specific for lactate. In conclusions, chronic hyperglycemia reduced substrate oxidation in skeletal muscle cells and impaired the metabolic switching. The effect is most likely due to an induced mitochondrial dysfunction.

2009-12-24 | GSE19620 | GEO

Transcription profiling of mouse skeletal muscle overexpressing PPARalpha

Project description:This experiment was conducted to identify target genes of the peroxisome proliferator-activated receptor alpha (PPARa) in skeletal muscle of transgenic mice that overexpressed PPARa. The following abstract from the published manuscript describes the major findings of this work. A potential link between muscle peroxisome proliferator- activated receptor-alpha signaling and obesity-related diabetes.Finck BN, Bernal-Mizrachi C, Han DH, Coleman T, Sambandam N, LaRiviere LL, Holloszy JO, Semenkovich CF, Kelly DP. The role of the peroxisome proliferator-activated receptor-alpha (PPARalpha) in the development of insulin-resistant diabetes was evaluated using gain- and loss-of-function approaches. Transgenic mice overexpressing PPARalpha in muscle (MCK-PPARalpha mice) developed glucose intolerance despite being protected from diet-induced obesity. Conversely, PPARalpha null mice were protected from diet-induced insulin resistance in the context of obesity. In skeletal muscle, MCK-PPARalpha mice exhibited increased fatty acid oxidation rates, diminished AMP-activated protein kinase activity, and reduced insulin-stimulated glucose uptake without alterations in the phosphorylation status of key insulin-signaling proteins. These effects on muscle glucose uptake involved transcriptional repression of the GLUT4 gene. Pharmacologic inhibition of fatty acid oxidation or mitochondrial respiratory coupling prevented the effects of PPARalpha on GLUT4 expression and glucose homeostasis. These results identify PPARalpha-driven alterations in muscle fatty acid oxidation and energetics as a potential link between obesity and the development of glucose intolerance and insulin resistance. Experiment Overall Design: RNA from two wild-type (non-transgenic (NTG)) and two PPARalpha overexpressing (MCK-PPARa) mice was analyzed. Two replicates of each are provided.

2008-06-14 | E-GEOD-5777 | biostudies-arrayexpress

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data