Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0015695 (fatty liver)
 13,941 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Multifaceted evidence links the development of liver tumours to the activation and proliferation of adult liver progenitor (oval) cells during the early stages of chronic liver injury. The aim of this study was to examine the role of the peroxisome proliferator activated receptors (PPARs): PPARalpha, delta and gamma, in mediating the behaviour of liver progenitor cells during pre-neoplastic disease and to investigate their potential as therapeutic targets for the treatment of chronic liver injury. We observed increased liver expression of PPARalpha and gamma in concert with expanding oval cell numbers during the first 21 days following commencement of the choline deficient, ethionine supplemented (CDE) dietary model of carcinogenic liver injury in mice. Both primary and immortalized liver progenitor cells were found to express PPARalpha, delta and gamma, but not gamma2, the alternate splice form of PPARgamma. WY14643 (PPARalpha agonist), GW501516 (PPARdelta agonist) and ciglitazone (PPARgamma agonist) were tested for their ability to modulate the behaviour of p53-immortalized liver (PIL) progenitor cell lines in vitro. Both PPARdelta and gamma agonists induced dose-dependent growth inhibition and apoptosis of PIL cells. In contrast, the PPARalpha agonist had no effect on PIL cell growth. None of the drugs affected the maturation of PIL cells along either the hepatocytic or biliary lineages, as judged by their patterns of hepatic gene expression prior to and following treatment. Administration of the PPARgamma agonist ciglitazone to mice fed with the CDE diet for 14 days resulted in a significantly diminished oval cell response and decreased fibrosis compared with those receiving placebo. In contrast, GW501516 did not affect oval cell numbers or liver fibrosis, but inhibited CDE-induced hepatic steatosis. In summary, PPARgamma agonists reduce oval cell proliferation and fibrosis during chronic liver injury and may be useful in the prevention of hepatocellular carcinoma.
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PMID:Inhibition of adult liver progenitor (oval) cell growth and viability by an agonist of the peroxisome proliferator activated receptor (PPAR) family member gamma, but not alpha or delta. 1591 8

CCAAT/enhancer-binding protein beta (C/EBPbeta) plays a key role in initiation of adipogenesis in adipose tissue and gluconeogenesis in liver; however, the role of C/EBPbeta in hepatic lipogenesis remains undefined. Here we show that C/EBPbeta inactivation in Lepr(db/db) mice attenuates obesity, fatty liver, and diabetes. In addition to impaired adipogenesis, livers from C/EBPbeta(-/-) x Lepr(db/db) mice had dramatically decreased triglyceride content and reduced lipogenic enzyme activity. C/EBPbeta deletion in Lepr(db/db) mice down-regulated peroxisome proliferator-activated receptor gamma2 (PPARgamma2) and stearoyl-CoA desaturase-1 and up-regulated PPARalpha independent of SREBP1c. Conversely, C/EBPbeta overexpression in wild-type mice increased PPARgamma2 and stearoyl-CoA desaturase-1 mRNA and hepatic triglyceride content. In FAO cells, overexpression of the liver inhibiting form of C/EBPbeta or C/EBPbeta RNA interference attenuated palmitate-induced triglyceride accumulation and reduced PPARgamma2 and triglyceride levels in the liver in vivo. Leptin and the anti-diabetic drug metformin acutely down-regulated C/EBPbeta expression in hepatocytes, whereas fatty acids up-regulate C/EBPbeta expression. These data provide novel evidence linking C/EBPbeta expression to lipogenesis and energy balance with important implications for the treatment of obesity and fatty liver disease.
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PMID:CCAAT/enhancer-binding protein beta deletion reduces adiposity, hepatic steatosis, and diabetes in Lepr(db/db) mice. 1738 71

The aim of present study was to identify the visceral adipose tissue genes differentially expressed in a well-characterized rat model of high-fat diet (HFD)-induced obesity. Male Sprague-Dawley rats were fed either the HFD (17 g lard + 3 g corn oil/100 g) or the normal diet (5 g corn oil/100 g) for 9 weeks. The HFD rats weighed 55% more and accumulated 85% to 133% greater visceral fats than did the normal-diet rats (P < .05). Animals given the HFD for 9 weeks acquired dyslipidemia, fatty liver, insulin resistance, and hyperleptinemia along with the overexpression of several obesity-related genes, such as leptin, tumor necrosis factor alpha, resistin, peroxisome proliferator-activated receptor gamma2, CCAAT/enhancer-binding protein alpha, and sterol regulatory element-binding protein-1c, in the epididymal adipose tissue. The differential gene expression profile obtained from the cDNA microarray analysis followed by the real-time polymerase chain reaction confirmation led to a recruitment of several uncharacterized adipose tissue genes responding to the HFD. We report herein, for the first time, that a series of genes which might be implicated in the insulin-stimulated glucose transporter 4 translocation, such as protein phosphatase 2 (formerly 2A), cell division cycle 42-interacting protein 4, syntaxin 6, linker of T-cell receptor pathways 10, as well as the genes which might be involved in cancer development, such as heat shock 10-kd protein 1, and ras-related C3 botulinum toxin substrate 1, were differentially expressed in the epididymal adipose tissue of rats rendered obese by an HFD.
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PMID:Genes are differentially expressed in the epididymal fat of rats rendered obese by a high-fat diet. 1908 40

Circulating ghrelin elevates abdominal adiposity by a mechanism independent of its central orexigenic activity. In this study we tested the hypothesis that peripheral ghrelin induces a depot-specific increase in white adipose tissue (WAT) mass in vivo by GH secretagogue receptor (GHS-R(1a))-mediated lipolysis. Chronic iv infusion of acylated ghrelin increased retroperitoneal and inguinal WAT volume in rats without elevating superficial sc fat, food intake, or circulating lipids and glucose. Increased retroperitoneal WAT mass resulted from adipocyte enlargement probably due to reduced lipid export (ATP-binding cassette transporter G1 mRNA expression and circulating free fatty acids were halved by ghrelin infusion). In contrast, ghrelin treatment did not up-regulate biomarkers of adipogenesis (peroxisome proliferator-activated receptor-gamma2 or CCAAT/enhancer binding protein-alpha) or substrate uptake (glucose transporter 4, lipoprotein lipase, or CD36) and although ghrelin elevated sterol-regulatory element-binding protein 1c expression, WAT-specific mediators of lipogenesis (liver X receptor-alpha and fatty acid synthase) were unchanged. Adiposity was unaffected by infusion of unacylated ghrelin, and the effects of acylated ghrelin were abolished by transcriptional blockade of GHS-R(1a), but GHS-R(1a) mRNA expression was similar in responsive and unresponsive WAT. Microarray analysis suggested that depot-specific sensitivity to ghrelin may arise from differential fine tuning of signal transduction and/or lipid-handling mechanisms. Acylated ghrelin also induced hepatic steatosis, increasing lipid droplet number and triacylglycerol content by a GHS-R(1a)-dependent mechanism. Our data imply that, during periods of energy insufficiency, exposure to acylated ghrelin may limit energy utilization in specific WAT depots by GHS-R(1a)-dependent lipid retention.
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PMID:Ghrelin induces abdominal obesity via GHS-R-dependent lipid retention. 1929 44

Obesity and hyperlipidemia are associated with impaired insulin sensitivity in human type 2 diabetes mellitus, possibly due to activation of a mild inflammatory response. Because obesity-induced insulin resistance predisposes cats to diabetes and because hyperlipidemia is a frequent concurrent finding, excess lipids may also impair insulin sensitivity in cats. Healthy cats (n=6) were infused with lipids (Lipovenoes 10%) for 10 days to clamp blood triglycerides at the approximate concentration of untreated feline diabetes (3-7 mmol/l). Controls received saline (n=5). On day 10, plasma adiponectin and proinflammatory markers were measured. Whole-body insulin sensitivity was calculated following an intravenous glucose tolerance test. Tissue mRNAs of glucose metabolism-related genes were quantified in subcutaneous and visceral fat, liver, and skeletal muscles. Accumulation of lipids was assessed in liver. At the termination of infusion, whole-body insulin sensitivity did not differ between groups. Compared to saline, cats infused with lipids had 50% higher plasma adiponectin and 2-3 times higher alpha(1)-acid glycoprotein and monocyte chemoattractant protein-1. Unexpectedly, lipid-infused cats had increased glucose transporter-4 (GLUT4) mRNA in the visceral fat, and increased peroxisome proliferative activated receptor-gamma2 (PPARgamma2) in subcutaneous fat; adiponectin expression was not affected in any tissue. Lipid-infused cats developed hepatic steatosis. Although hyperlipidemia induced systemic inflammation, whole-body insulin sensitivity was not impaired after 10 day infusion. Increased circulating adiponectin may have contributed to prevent insulin resistance, possibly by increasing GLUT4 and PPARgamma2 transcripts in fat depots.
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PMID:10-day hyperlipidemic clamp in cats: effects on insulin sensitivity, inflammation, and glucose metabolism-related genes. 2016 4