Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Regulatory role for phosphatidylcholine transfer protein/StarD2 in the metabolic response to peroxisome proliferator activated receptor alpha (PPARalpha).

ABSTRACT: Phosphatidylcholine transfer protein (PC-TP, a.k.a. StarD2) is abundantly expressed in liver and is regulated by PPARalpha. When fed the synthetic PPARalpha ligand fenofibrate, Pctp(-/-) mice exhibited altered lipid and glucose metabolism. Microarray profiling of livers from fenofibrate fed wild type and Pctp(-/-) mice revealed differential expression of a broad array of metabolic genes, as well as their regulatory transcription factors. PC-TP expression in cell culture controlled the activities of both PPARalpha and HNF4alpha, suggesting that the mechanism by which it modulates hepatic metabolism is at least in part via activation of transcription factors that govern nutrient homeostasis.

SUBMITTER: Kang HW

PROVIDER: S-EPMC2826570 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Regulatory role for phosphatidylcholine transfer protein/StarD2 in the metabolic response to peroxisome proliferator activated receptor alpha (PPARalpha).

Kang Hye Won HW Kanno Keishi K Scapa Erez F EF Cohen David E DE

Biochimica et biophysica acta 20100104 4

Phosphatidylcholine transfer protein (PC-TP, a.k.a. StarD2) is abundantly expressed in liver and is regulated by PPARalpha. When fed the synthetic PPARalpha ligand fenofibrate, Pctp(-/-) mice exhibited altered lipid and glucose metabolism. Microarray profiling of livers from fenofibrate fed wild type and Pctp(-/-) mice revealed differential expression of a broad array of metabolic genes, as well as their regulatory transcription factors. PC-TP expression in cell culture controlled the activities ...[more]

PMID: 20045742

Similar Datasets

Examination of Ligand-Dependent Coactivator Recruitment by Peroxisome Proliferator-Activated Receptor-alpha (PPARalpha).

Project description:The ligand-dependent recruitment of coactivators to peroxisome proliferator-activated receptor-alpha (PPARalpha) was examined. PPAR-binding protein (PBP), PPARgamma coactivator-1alpha (PGC-1alpha), steroid receptor coactivator-1 (SRC-1), and CBP/p300-interacting transactivator with ED-rich tail 2 (CITED2) affected PPARalpha activity in the presence of Wy-14,643. The effects on PPARalpha activity in light of increased or decreased expression of these coactivators were qualitatively different depending on the ligand examined. Diminished expression of PGC-1alpha, SRC-1, or PBP by RNAi plasmids affected natural or synthetic agonist activity whereas only Wy-14,643 was affected by decreased PGC-1alpha. The interaction of PPARalpha with an LXXLL-containing peptide library showed ligand-specific patterns, indicative of differences in conformational change. The association of coactivators to PPARalpha occurs predominantly via the carboxyl-terminus and mutating (456)LHPLL to (456)LHPAA resulted in a dominant-negative construct. This research confirms that coactivator recruitment to PPARalpha is ligand-dependent and that selective receptor modulators (SRMs) of this important protein are likely.

| S-EPMC1664713 | biostudies-literature

Regulatory Role for PC-TP/StarD2 in the Metabolic Response to Peroxisome Proliferator Activated Receptor Alpha (PPARα)

Project description:Phosphatidylcholine transfer protein (PC-TP, a.k.a StarD2) is abundantly expressed in liver and is regulated by PPARα. When fed the synthetic PPARα ligand fenofibrate, Pctp-/- mice exhibited altered lipid and glucose homeostasis. Microarray profiling of liver from fenofibrate fed wild type and Pctp-/- mice revealed differential expression of a broad array of metabolic genes, as well as their regulatory transcription factors. Because its expression controlled the transcriptional activities of both PPARα and HNF4α in cell culture, the broader impact of PC-TP on nutrient metabolism is most likely secondary to its role in fatty acid metabolism. 6 livers collected from PC-TP knockout mice fed a fenobrate-supplemented diet were used as the experimental group. 6 livers collected from wild type mice fed a fenofibrate-supplemented diet were used as the control group. RNA prepared from one liver was used to hybridize one GeneChip, so that there were 6 experimental GeneChips and 6 control GeneChips.

2010-08-12 | E-GEOD-17666 | biostudies-arrayexpress

CLOCK is involved in the circadian transactivation of peroxisome-proliferator-activated receptor alpha (PPARalpha) in mice.

Project description:PPARalpha (peroxisome-proliferator-activated receptor alpha) is a member of the nuclear receptor superfamily of ligand-activated transcription factors that regulate the expression of genes associated with lipid metabolism. In the present study, we show that circadian expression of mouse PPARalpha mRNA requires the basic helix-loop-helix PAS (Per-Arnt-Sim) protein CLOCK, a core component of the negative-feedback loop that drives circadian oscillators in mammals. The circadian expression of PPARalpha mRNA was abolished in the liver of homozygous Clock mutant mice. Using wild-type and Clock-deficient fibroblasts derived from homozygous Clock mutant mice, we showed that the circadian expression of PPARalpha mRNA is regulated by the peripheral oscillators in a CLOCK-dependent manner. Transient transfection and EMSAs (electrophoretic mobility-shift assays) revealed that the CLOCK-BMAL1 (brain and muscle Arnt-like protein 1) heterodimer transactivates the PPARalpha gene via an E-box-rich region located in the second intron. This region contained two perfect E-boxes and four E-box-like motifs within 90 bases. ChIP (chromatin immunoprecipitation) also showed that CLOCK associates with this E-box-rich region in vivo. Circadian expression of PPARalpha mRNA was intact in the liver of insulin-dependent diabetic and of adrenalectomized mice, suggesting that endogenous insulin and glucocorticoids are not essential for the rhythmic expression of the PPARalpha gene. These results suggested that CLOCK plays an important role in lipid homoeostasis by regulating the transcription of a key protein, PPARalpha.

| S-EPMC1134877 | biostudies-literature

Regulatory Role for PC-TP/StarD2 in the Metabolic Response to Peroxisome Proliferator Activated Receptor Alpha (PPARα)

2010-08-12 | GSE17666 | GEO

Proline- and acidic amino acid-rich basic leucine zipper proteins modulate peroxisome proliferator-activated receptor alpha (PPARalpha) activity.

Project description:In mammals, many aspects of metabolism are under circadian control. At least in part, this regulation is achieved by core-clock or clock-controlled transcription factors whose abundance and/or activity oscillate during the day. The clock-controlled proline- and acidic amino acid-rich domain basic leucine zipper proteins D-site-binding protein, thyrotroph embryonic factor, and hepatic leukemia factor have previously been shown to participate in the circadian control of xenobiotic detoxification in liver and other peripheral organs. Here we present genetic and biochemical evidence that the three proline- and acidic amino acid-rich basic leucine zipper proteins also play a key role in circadian lipid metabolism by influencing the rhythmic expression and activity of the nuclear receptor peroxisome proliferator-activated receptor α (PPARα). Our results suggest that, in liver, D-site-binding protein, hepatic leukemia factor, and thyrotroph embryonic factor contribute to the circadian transcription of genes specifying acyl-CoA thioesterases, leading to a cyclic release of fatty acids from thioesters. In turn, the fatty acids act as ligands for PPARα, and the activated PPARα receptor then stimulates the transcription of genes encoding proteins involved in the uptake and/or metabolism of lipids, cholesterol, and glucose metabolism.

| S-EPMC3064322 | biostudies-literature

Metabolic adaptation to intermittent fasting is independent of peroxisome proliferator-activated receptor alpha.

Project description:BACKGROUND:Peroxisome proliferator-activated receptor alpha (PPARA) is a major regulator of fatty acid oxidation and severe hepatic steatosis occurs during acute fasting in Ppara-null mice. Thus, PPARA is considered an important mediator of the fasting response; however, its role in other fasting regiments such as every-other-day fasting (EODF) has not been investigated. METHODS:Mice were pre-conditioned using either a diet containing the potent PPARA agonist Wy-14643 or an EODF regimen prior to acute fasting. Ppara-null mice were used to assess the contribution of PPARA activation during the metabolic response to EODF. Livers were collected for histological, biochemical, qRT-PCR, and Western blot analysis. RESULTS:Acute fasting activated PPARA and led to steatosis, whereas EODF protected against fasting-induced hepatic steatosis without affecting PPARA signaling. In contrast, pretreatment with Wy-14,643 did activate PPARA signaling but did not ameliorate acute fasting-induced steatosis and unexpectedly promoted liver injury. Ppara ablation exacerbated acute fasting-induced hypoglycemia, hepatic steatosis, and liver injury in mice, whereas these detrimental effects were absent in response to EODF, which promoted PPARA-independent fatty acid metabolism and normalized serum lipids. CONCLUSIONS:These findings indicate that PPARA activation prior to acute fasting cannot ameliorate fasting-induced hepatic steatosis, whereas EODF induced metabolic adaptations to protect against fasting-induced steatosis without altering PPARA signaling. Therefore, PPARA activation does not mediate the metabolic adaptation to fasting, at least in preventing acute fasting-induced steatosis.

| S-EPMC5784329 | biostudies-literature

Role of peroxisome proliferator-activated receptor {delta}/{beta} in hepatic metabolic regulation.

Project description:Pharmacological activation of peroxisome proliferator-activated receptor ?/? (PPAR?/?) improves glucose handling and insulin sensitivity. The target tissues of drug actions remain unclear. We demonstrate here that adenovirus-mediated liver-restricted PPAR? activation reduces fasting glucose levels in chow- and high fat-fed mice. This effect is accompanied by hepatic glycogen and lipid deposition as well as up-regulation of glucose utilization and de novo lipogenesis pathways. Promoter analyses indicate that PPAR? regulates hepatic metabolic programs through both direct and indirect transcriptional mechanisms partly mediated by its co-activator, PPAR? co-activator-1?. Assessment of the lipid composition reveals that PPAR? increases the production of monounsaturated fatty acids, which are PPAR activators, and reduces that of saturated FAs. Despite the increased lipid accumulation, adeno-PPAR?-infected livers exhibit less damage and show a reduction in JNK stress signaling, suggesting that PPAR?-regulated lipogenic program may protect against lipotoxicity. The altered substrate utilization by PPAR? also results in a secondary effect on AMP-activated protein kinase activation, which likely contributes to the glucose-lowering activity. Collectively, our data suggest that PPAR? controls hepatic energy substrate homeostasis by coordinated regulation of glucose and fatty acid metabolism, which provide a molecular basis for developing PPAR? agonists to manage hyperglycemia and insulin resistance.

| S-EPMC3020731 | biostudies-literature

Inflammatory pathways are activated during cardiomyocyte hypertrophy and attenuated by peroxisome proliferator-activated receptors PPARalpha and PPARdelta.

Project description:Accumulating evidence indicates an important role for inflammation in cardiac hypertrophy and failure. Peroxisome proliferator-activated receptors (PPARs) have been reported to attenuate inflammatory signaling pathways and, as such, may interfere with cardiac remodeling. Accordingly, the objectives of the present study were to explore the relationship between cardiomyocyte hypertrophy and inflammation and to investigate whether PPARalpha and PPARdelta are able to inhibit NF-kappaB activation and, consequently, the hypertrophic growth response of neonatal rat cardiomyocytes (NCM). mRNA levels of markers of both hypertrophy and inflammation were increased following treatment with the pro-hypertrophic factor phenylephrine (PE) or the chemokine TNF-alpha. Induction of inflammatory genes was found to be fast (within 2 h after stimulation) and transient, while induction of hypertrophic marker genes was more gradual (peaking at 24-48 h). Inflammatory and hypertrophic pathways appeared to converge on NF-kappaB as both PE and TNF-alpha increased NF-kappaB binding activity as measured by electrophoretic mobility shift assay. Following transient transfection, the p65-induced transcriptional activation of a NF-kappaB reporter construct was significantly blunted after co-transfection of PPARalpha or PPARdelta in the presence of their respective ligands. Finally, adenoviral overexpression of PPARalpha and PPARdelta markedly attenuated cell enlargement and the expression of hypertrophic marker genes in PE-stimulated NCM. The collective findings reveal a close relationship between hypertrophic and inflammatory signaling pathways in the cardiomyocyte. It was shown that both PPARalpha and PPARdelta are able to mitigate cardiomyocyte hypertrophy in vitro by inhibiting NF-kappaB activation.

| S-EPMC2662011 | biostudies-literature

Peroxisome proliferator-activated receptor-α accelerates α-chlorofatty acid catabolism.

Project description:α-Chlorofatty aldehydes are generated from myeloperoxidase-derived HOCl targeting plasmalogens, and are subsequently oxidized to α-chlorofatty acids (α-ClFAs). The catabolic pathway for α-ClFA is initiated by ω-oxidation. Here, we examine PPAR-α activation as a mechanism to increase α-ClFA catabolism. Pretreating both HepG2 cells and primary mouse hepatocytes with the PPAR-α agonist, pirinixic acid (Wy 14643), increased the production of α-chlorodicarboxylic acids (α-ClDCAs) in cells treated with exogenous α-ClFA. Additionally, α-ClDCA production in Wy 14643-pretreated wild-type mouse hepatocytes was accompanied by a reduction in cellular free α-ClFA. The dependence of PPAR-α-accelerated α-ClFA catabolism was further demonstrated by both impaired metabolism in mouse PPAR-α-/- hepatocytes and decreased clearance of plasma α-ClFA in PPAR-α-/- mice. Furthermore, Wy 14643 treatments decreased plasma 2-chlorohexadecanoic acid levels in wild-type mice. Additional studies showed that α-ClFA increases PPAR-α, PPAR-δ, and PPAR-γ activities, as well as mRNA expression of the PPAR-α target genes, CD36, CPT1a, Cyp4a10, and CIDEC. Collectively, these results indicate that PPAR-α accelerates important pathways for the clearance of α-ClFA, and α-ClFA may, in part, accelerate its catabolism by serving as a ligand for PPAR-α.

| S-EPMC5282948 | biostudies-literature

Role of peroxisome proliferator-activated receptor alpha in disease of pancreatic beta cells.

Project description:Expression of peroxisome proliferator-activated receptor alpha (PPARalpha) and enzymes of fatty acid (FA) oxidation is markedly reduced in the fat-laden, dysfunctional islets of obese, prediabetic Zucker diabetic fatty (fa/fa) rats with mutated leptin receptors (OB-R). Leptin, PPARalpha/retinoid x receptor ligands, and FA all up-regulate PPARalpha and enzymes of FA oxidation and stimulate [3H]-palmitate oxidation in normal islets but not in islets from fa/fa rats. Overexpression of normal OB-R in islets of fa/fa rats corrects all of the foregoing abnormalities and reverses the diabetic phenotype. PPARalpha is a OB-R-dependent factor required for normal fat homeostasis in islet cells.

| S-EPMC21174 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

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