Dataset Information

Acute deletion of the glucocorticoid receptor in hepatocytes disrupts postprandial lipid metabolism

ABSTRACT: Hepatic lipid metabolism is highly dynamic, and disruption of several circadian transcriptional regulators results in hepatic steatosis. This includes genetic disruption of the glucocorticoid receptor (GR) as the liver develops. To address the functional role of GR in the adult liver, we used an acute hepatocyte-specific GR knockout model (hepGRKO) to study temporal hepatic lipid metabolism governed by GR at several pre- and postprandial timepoints. Lipidomics analysis revealed significant temporal lipid metabolism, with GR disruption resulting in impaired regulation of specific triglycerides, non-esterified fatty acids, and sphingolipids. This correlated with increased number and size of lipid droplets and mildly reduced mitochondrial respiration, most noticeably in the postprandial phase. Proteomics and transcriptomics analyses suggest that dysregulated lipid metabolism originates from pronounced induced expression of enzymes involved in fatty acid synthesis, -oxidation, and sphingolipid metabolism. Integration of GR cistromic data suggests that induced genes are a result of regulatory actions secondary to direct GR effects on transcription.

INSTRUMENT(S): Orbitrap Exploris 480

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Liver

SUBMITTER: Felix Boel Pedersen

LAB HEAD: Blagoy Blagoev

PROVIDER: PXD041168 | Pride | 2023-09-07

REPOSITORIES: pride

ACCESS DATA

Dataset's files

Source:

			Action	DRS
	27042021_FP_MLiver_Circadian_LG01.raw	Raw
	27042021_FP_MLiver_Circadian_LG02.raw	Raw
	27042021_FP_MLiver_Circadian_LG03.raw	Raw
	27042021_FP_MLiver_Circadian_LG04.raw	Raw
	27042021_FP_MLiver_Circadian_LG05.raw	Raw

Items per page:

1 - 5 of 42

Publications

Acute Deletion of the Glucocorticoid Receptor in Hepatocytes Disrupts Postprandial Lipid Metabolism in Male Mice.

Correia Catarina Mendes CM Præstholm Stine Marie SM Havelund Jesper Foged JF Pedersen Felix Boel FB Siersbæk Majken Storm MS Ebbesen Morten Frendø MF Gerhart-Hines Zach Z Heeren Joerg J Brewer Jonathan J Larsen Steen S Blagoev Blagoy B Færgeman Nils Joakim NJ Grøntved Lars L

Endocrinology 20230801 10

Hepatic lipid metabolism is highly dynamic, and disruption of several circadian transcriptional regulators results in hepatic steatosis. This includes genetic disruption of the glucocorticoid receptor (GR) as the liver develops. To address the functional role of GR in the adult liver, we used an acute hepatocyte-specific GR knockout model to study temporal hepatic lipid metabolism governed by GR at several preprandial and postprandial circadian timepoints. Lipidomics analysis revealed significan ...[more]

PMID: 37610219

Similar Datasets

Project description:Background and Aims: Inflammasome-mediated caspase-1 activity regulates the maturation and release of the pro-inflammatory cytokines interleukin (IL)-1M-CM-^_ and IL-18. Recently, we showed that caspase-1 deficiency strongly reduces high fat diet-induced adiposity although the mechanism is still unclear. We now aimed to elucidate the mechanism by which caspase-1 deficiency reduces modulates resistance to high fat diet-feeding fat accumulation in adipose tissue by focusing on the role of caspase-1 in the regulation of triglyceride (TG)-rich lipoprotein metabolism. Methods: Caspase-1 deficient and wild-type mice (both C57Bl/6 background) were used to determine postprandial TG kinetics, intestinal TG absorption, VLDL-TG production as well as TG clearance, all of which strongly contribute to the supply of TG for storage in adipose tissue. Micro-array and qPCR analysis were used to unravel intestinal and hepatic metabolic pathways involved. Results: Caspase-1 deficiency reduced the postprandial response to an oral lipid load, while tissue specific clearance of TG-rich lipoproteins was not changed. Indeed, an oral olive oil gavage containing [3H]TG revealed that caspase-1 deficiency significantly decreased intestinal chylomicron-TG production and reduced the uptake of [3H]TG-derived FA by liver, muscle, and adipose tissue. Similarly, caspase-1 deficiency reduced the hepatic VLDL-TG production without reducing VLDL-apoB production, despite an elevated hepatic TG content. Pathway analysis revealed that caspase-1 deficiency reduces intestinal and hepatic expression of genes involved in lipogenesis. Conclusions: Absence of caspase-1 reduces assembly and secretion of TG-rich lipoproteins, thereby reducing the availability of TG-derived FA for uptake by peripheral organs including adipose tissue. We anticipate that caspase-1 represents a novel link between innate immunity and lipid metabolism. Keywords: Expression profiling by array Wild-type (WT) and Casp1-null mice were maintained at lab chow. Animals, aged between 14 and 16 weeks (n=3 per genotype), were killed and liver and intestinal segments were removed. Livers were isolated from mice that were fasted over night, whereas intesines were removed from mice 2 hrs after they received an oral lipid load.Total RNA was isolated and subjected to gene expression profiling.

Project description:Transcriptional profiling of insulin exposed H4IIE cells at different time points (6h-24h) to 100 nM insulin, with untreated solvent control cells (blanks). The central role of hepatic insulin resistance in pandemic metabolic diseases urges investigation of the underlying mechanisms of its development and pathogenesis. Besides genetic susceptibility and lifestyle factors, environmental pollutants are suggested risk factors. In order to appraise the role of the thousands of pollutants we are daily exposed to, stable, robust and high throughput cell-based systems should be developed. In this context, it is of paramount importance to select an in vitro system which mimics in vivo insulin responses as close as possible. Therefore, this study was designed to evaluate if the rat H4IIE hepatoma cell line is a physiologically relevant model to study hepatic insulin responses. DNA microarray analysis, real-time PCR and flow cytometric cell cycle analysis were used to assess the relevance of the insulin response in H4IIE cells. Insulin dose dependently stimulated H4IIE growth. Time dependency of the insulin response was shown with real-time PCR for the known insulin responsive genes: Fasn, Pck1 and Irs2. Based on these results, microarray analysis was performed on H4IIE cells exposed to insulin (100 nM) for 6h and 24h. Genes related to carbohydrate (glycolysis and gluconeogenesis) and lipid metabolism (glycerolipid metabolism, cholesterol synthesis and fatty acid oxidation) were most profoundly afflicted, in accordance with in vivo insulin action in liver. Since changes in carbohydrate and lipid metabolism are pivotal in the pathogenesis of insulin resistance, the presence of a physiological relevant insulin response in H4IIE cells pleads for further testing of its potential use in research on pollutant-driven insulin resistance. Microarray analysis was performed on H4IIE cells exposed to insulin (100 nM) for 6h and 24h. A separate v+2 A-optimal hybridization design was used for each time-point. Using this design each exposure condition is represented by three biological replicates, with each biological replicate analysed in technical duplicate while applying the dye swap principle to correct for dye bias.

Project description:Chronic stress leads post-traumatic stress disorder (PTSD) and to metabolic complications, including fatty liver. It is feasible, that stress immediately initiates molecular mechanisms to alter energy metabolism and glucose homeostasis which interfere with hepatic lipid accumulation after stress recovery. We aim to elucidate these molecular mechanisms of long term stress effects on metabolism and focus on physiological adaptation and the role of FGF21, which is protective in hepatic lipid accumulation. Methods FGF21 knockout and control mice were exposed to chronic variable stress (Cvs) and recovered for 3 months to simulate PTSD. We determined in vivo and ex vivo energy metabolism, mitochondrial function by extracellular flux analysis, alterations in DNA modifying enzymes and gene regulation immediately after stress and after the recovery period to determine long term alterations. Results Chronic stress leads to reduced insulin sensitivity and hepatic lipid accumulation with increased fatty acid uptake (FAU), stress-induced lipolysis, and reduction in NAD+/NAD ratio and Sirt activity. Immediately after stress, PPARa and SREBP-1 target genes are differentially regulated and are involved in the development of stress-induced fatty liver. After recovery, insulin sensitivity increases but insulin-induced de novo lipogenesis (DNL) is reduced and FAU is increased. HDAC and MT activity are suppressed, whereas HAT activity increases, linking metabolic adjustments to transcriptional regulators. Thus, key metabolic genes are differentially regulated and secreted proteins indicate the activation of liver disease by Cvs only in FGF21WT. GR binding to the Cd36 promoter is altered. After stress recovery, serum FGF21 is increased and protects against lipid accumulation. FGF21 interacts by attenuating DNL, increasing FAU and HAT activity, and balancing mitochondrial activity. Higher long-term stress-induced activation and binding of GR to the FGF21 promoter may contribute to the prolonged FGF21 release. Conclusions We show that previous stress exposure determines predisposition to fatty liver disease is regulated by FGF21. Immediately after Cvs, altered gene regulation and activity of DNA-modifying enzymes determine the metabolic late effects seen in PTSD. FGF21 functions after chronic stress exposure i) to protect against hepatic lipid accumulation, ii) to maintain mitochondrial capacity, and iii) to mediate in the modulation of DNA-modifying enzymes. These findings highlight the protective role of FGF21 even in stress-induced hepatic lipid accumulation.