Similar Datasets
Project description:Regulation of nutrient status during fasting and refeeding plays an important role in maintaining metabolic homeostasis in the liver. Thus, we investigated the impact of the physiological fed–fasted–refed cycle on hepatic gene expression in nutrient-sensitive mice. We performed transcriptomic analysis of liver samples in fed, fasted and refed groups of mice. Through mRNA-sequencing (RNA-Seq) and miRNA-Seq, we compared fasted and fed states (fasted versus fed cohort) as well as refed and fasted states (refed versus fasted cohort) to detect dynamic alterations of hepatic mRNA– miRNA expression during the fed–fasted–refed cycle
2023-02-24 | GSE225696 | GEO
Project description:Regulation of nutrient status during fasting and refeeding plays an important role in maintaining metabolic homeostasis in the liver. Thus, we investigated the impact of the physiological fed–fasted–refed cycle on hepatic gene expression in nutrient-sensitive mice. We performed transcriptomic analysis of liver samples in fed, fasted and refed groups of mice. Through mRNA-sequencing (RNA-Seq) and miRNA-Seq, we compared fasted and fed states (fasted versus fed cohort) as well as refed and fasted states (refed versus fasted cohort) to detect dynamic alterations of hepatic mRNA– miRNA expression during the fed–fasted–refed cycle
2023-02-24 | GSE225695 | GEO
Project description:To determine whether the antilipogenic actions of insulin-induced gene 1 (insig-1) demonstrated in cultured preadipocytes also occur in vivo, we infected Zucker diabetic fatty (ZDF) (fa/fa) rats, with recombinant adenovirus containing insig-1 or -2 cDNA. An increase of both proteins appeared in their livers. In control ZDF (fa/fa) rats infected with adenovirus containing the beta-galactosidase (beta-gal) cDNA, triacylglycerols in the liver and plasma rose steeply whereas the insig-infected rats exhibited substantial attenuation of the increase in hepatic steatosis and hyperlipidemia. Insig overexpression was associated with a striking reduction in the elevated level of nuclear sterol regulatory element-binding protein (SREBP)-1c, the activated form of the transcription factor. The mRNA of SREBP-1c lipogenic target enzymes also fell. The mRNA of endogenous insig-1, but not -2a and -2b, was higher in the fatty livers of untreated obese ZDF (fa/fa) rats compared with controls, but the elevation was not sufficient to block the approximately 3-fold increase in SREBP-1c expression and activity. In normal animals, adenovirus-induced overexpression of the insigs reduced the increase in SREBP-1c mRNA and its target enzymes caused by refeeding. The findings demonstrated that both insigs have antilipogenic action when transgenically overexpressed in livers with increased SREBP-1c-mediated lipogenesis. However, the increase in endogenous insig-1 expression associated with augmented lipogenesis may limit it, but is insufficient to prevent it.
| S-EPMC406473 | biostudies-literature
Project description:Spatial heterogeneity and plasticity of the mammalian liver is critical for systemic metabolic homeostasis in response to fluctuating nutritional status. Here, we generated a high-resolution transcriptomic landscape of the livers from mice that were either fed chow (fed), fasted for 18 h (fasted), or fasted for 18 h and then refed for 6 h (refed) using spatial transcriptomics (ST) and quantified changes in gene expression. This work provides a critical foundation for future mechanistic studies of liver metabolic heterogeneity and plasticity, and will help to understand the zonated pathology during liver disease progression.
2023-01-12 | GSE222796 | GEO
Project description:Signaling through GPR109a, the putative receptor for the endogenous ligand β-OH butyrate, inhibits adipose tissue lipolysis. Niacin, an anti-atherosclerotic drug that can induce insulin resistance, activates GPR109a at nM concentrations. GPR109a is not essential for niacin to improve serum lipid profiles. To better understand the involvement of GPR109a signaling in regulating glucose and lipid metabolism, we treated GPR109a wild-type (+/+) and knockout (-/-) mice with repeated overnight injections of saline or niacin in physiological states characterized by low (ad libitum fed) or high (16 h fasted) concentrations of the endogenous ligand, β-OH butyrate. In the fed state, niacin increased expression of apolipoprotein-A1 mRNA and decreased sterol regulatory element-binding protein 1 mRNA independent of genotype, suggesting a possible GPR109a independent mechanism by which niacin increases high-density lipoprotein (HDL) production and limits transcriptional upregulation of lipogenic genes. Niacin decreased fasting serum non-esterified fatty acid concentrations in both GPR109a +/+ and -/- mice. Independent of GPR109a expression, niacin blunted fast-induced hepatic triglyceride accumulation and peroxisome proliferator-activated receptor α mRNA expression. Although unaffected by niacin treatment, fasting serum HDL concentrations were lower in GPR109a knockout mice. Surprisingly, GPR109a knockout did not affect glucose or lipid homeostasis or hepatic gene expression in either fed or fasted mice. In turn, GPR109a does not appear to be essential for the metabolic response to the fasting ketogenic state or the acute effects of niacin.
| S-EPMC8069761 | biostudies-literature
Project description:We studied whether the accumulation of lipids in the fasted kidney are derived from lipoproteins or (non-esterified fatty acids) NEFAs. With overnight fasting, kidneys accumulated triglyceride, but had reduced levels of ceramide and glycosphingolipid species. Fasting led to a nearly 5-fold increase in kidney uptake of plasma [14C]oleic acid. Increasing circulating NEFAs using a β adrenergic receptor agonist caused a 15-fold greater accumulation of lipid in the kidney, while mice with reduced NEFAs due to adipose tissue deficiency of adipose triglyceride lipase had reduced triglycerides. Cluster of differentiation (Cd)36 mRNA increased 2-fold, and angiopoietin-like 4 (Angptl4), an LPL inhibitor, increased 10-fold. Fasting-induced kidney lipid accumulation was not affected by inhibition of LPL with poloxamer 407 or by use of mice with induced genetic LPL deletion. Despite the increase in CD36 expression with fasting, genetic loss of CD36 did not alter fatty acid uptake or triglyceride accumulation. Our data demonstrate that fasting-induced triglyceride accumulation in the kidney correlates with the plasma concentrations of NEFAs, but is not due to uptake of lipoprotein lipids and does not involve the fatty acid transporter, CD36.
2017-12-15 | GSE108106 | GEO
Project description:Liver homogenates produced from fasted and non-fasted C57BL/6J female mice were assayed for total lipolytic activity measured as hydrolysis of [9,10-(3)H(N)]-triolein into [(3)H] free fatty acids (FFA). Liver homogenates were also used for immunoblotting to determine levels of the lipolytic enzymes adipose-triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL), as well as site specific phosphorylation at the 14-3-3 binding site of ATGL and the serine 565 and serine 660 sites of HSL. Significantly higher triolein hydrolysis activity was observed in fasted liver samples, as well as a significant increase in total ATGL and a significant decrease in HSL phosphorylation at the S565 site.
| S-EPMC4802677 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2014-08-08 | E-GEOD-60103 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2013-05-01 | E-GEOD-45733 | biostudies-arrayexpress
Project description:Liver RNA and protein breakdown rates were measured simultaneously in fed and in 24 h-fasted rats during a short-term cyclic perfusion, 1 h after an intraperitoneal injection of glucagon or of saline. RNA was labelled in vivo by an intraperitoneal injection of [6-14C]orotic acid, 60 h before the start of the perfusion. The accumulation of radioactive cytidine and valine in the perfusion medium for 15 min was used to determine RNA breakdown and proteolysis respectively. The portal glucagon/insulin ratio was significantly higher in the fasted glucagon-treated rats than in their fed counterparts. Although glucagon administration significantly increased RNA and protein degradation rates in the fasted and in the fed groups, the effect was greater after 24 h of starvation. The relationship between these biochemical changes and the alterations of the hepatocyte lysosomal system was investigated by determining the fractional cytoplasmic volume of lysosomal structures (autophagic vacuoles and dense bodies) by morphometry in the fasted glucagon-treated rats and in their controls. Hyperlucagonaemia significantly enhanced the relative volume of autophagic vacuoles without affecting that of dense bodies. The results showed that hyperglucagonaemia induced in vivo stimulated both liver RNA and protein breakdown and that this effect was modulated by the nutritional status of the rats.
| S-EPMC1138069 | biostudies-other