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Hepatic Peroxisome Proliferator-Activated Receptor Gamma Signaling Contributes to Alcohol-Induced Hepatic Steatosis and Inflammation in Mice.

ABSTRACT: BACKGROUND:Peroxisome proliferator-activated receptor gamma (PPAR?) signaling has been shown to regulate lipogenesis and lipid accumulation. Previous studies have shown that hepatic PPAR? is up-regulated in steatotic liver of both animal and human. However, the effects of hepatic PPAR? signaling on alcoholic liver disease (ALD) remain elusive. METHODS:To determine the role of hepatic PPAR? signaling on ALD, wild-type (WT) and hepatocyte-specific PPAR? knockdown (PPAR??Hep) mice were fed a modified Lieber-DeCarli alcohol or isocaloric maltose dextrin control liquid diet for 8 weeks to induce ALD. Blood parameters, hepatic steatosis, and inflammation were measured after 8-week alcohol feeding. RESULTS:Alcohol feeding to WT mice resulted in liver damage (alanine aminotransferase [ALT], 94.68 ± 17.05 U/L; aspartate aminotransferase [AST], 55.87 ± 11.29 U/L), which was significantly alleviated by hepatic PPAR? knockdown (ALT, 57.36 ± 14.98 U/L; AST, 38.06 ± 3.35 U/L). Alcohol feeding led to marked lipid accumulation and up-regulation of lipogenic genes including fatty acid transport protein 1 (FATP1), acetyl-CoA carboxylase (ACC), fatty acid synthase (FASN), lipin1 (LIPIN1), diacylglycerol acyltransferase 1 (DGAT1), and diacylglycerol acyltransferase 2 (DGAT2) in the livers of WT mice. Knockdown of hepatic PPAR? significantly alleviated alcohol-induced lipid accumulation and abolished the up-regulation of FASN, DGAT1, and DGAT2. Silencing of PPAR? in FL83B cells significantly decreased ethanol (EtOH)-, linoleic acid-, and EtOH plus linoleic acid-induced lipid accumulation. Knockdown of hepatic PPAR? also significantly reduced alcohol-induced inflammatory chemokine (monocyte chemotactic protein 1 [MCP1], keratinocyte-derived chemokine [KC], interferon gamma-induced protein 10 [IP-10]) and inflammatory infiltration (lymphocyte antigen 6 complex, locus G [Ly6G], and F4/80). CONCLUSIONS:The results suggest that hepatic PPAR? signaling contributes to alcohol-induced liver injury by promoting hepatic steatosis and inflammation.

SUBMITTER: Zhang W

PROVIDER: S-EPMC5742869 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Hepatic Peroxisome Proliferator-Activated Receptor Gamma Signaling Contributes to Alcohol-Induced Hepatic Steatosis and Inflammation in Mice.

Zhang Wenliang W Sun Qian Q Zhong Wei W Sun Xinguo X Zhou Zhanxiang Z

Alcoholism, clinical and experimental research 20160408 5

<h4>Background</h4>Peroxisome proliferator-activated receptor gamma (PPARγ) signaling has been shown to regulate lipogenesis and lipid accumulation. Previous studies have shown that hepatic PPARγ is up-regulated in steatotic liver of both animal and human. However, the effects of hepatic PPARγ signaling on alcoholic liver disease (ALD) remain elusive.<h4>Methods</h4>To determine the role of hepatic PPARγ signaling on ALD, wild-type (WT) and hepatocyte-specific PPARγ knockdown (PPARγ∆Hep) mice we ...[more]

PMID: 27062444

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Dataset Information

Hepatic Peroxisome Proliferator-Activated Receptor Gamma Signaling Contributes to Alcohol-Induced Hepatic Steatosis and Inflammation in Mice.

Publications

Hepatic Peroxisome Proliferator-Activated Receptor Gamma Signaling Contributes to Alcohol-Induced Hepatic Steatosis and Inflammation in Mice.

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