Activation of CDK4 Triggers Development of Non-alcoholic Fatty Liver Disease

Cell Rep. 2016 Jul 19;16(3):744-56. doi: 10.1016/j.celrep.2016.06.019. Epub 2016 Jun 30.

Abstract

The development of non-alcoholic fatty liver disease (NAFLD) is a multiple step process. Here, we show that activation of cdk4 triggers the development of NAFLD. We found that cdk4 protein levels are elevated in mouse models of NAFLD and in patients with fatty livers. This increase leads to C/EBPα phosphorylation on Ser193 and formation of C/EBPα-p300 complexes, resulting in hepatic steatosis, fibrosis, and hepatocellular carcinoma (HCC). The disruption of this pathway in cdk4-resistant C/EBPα-S193A mice dramatically reduces development of high-fat diet (HFD)-mediated NAFLD. In addition, inhibition of cdk4 by flavopiridol or PD-0332991 significantly reduces development of hepatic steatosis, the first step of NAFLD. Thus, this study reveals that activation of cdk4 triggers NAFLD and that inhibitors of cdk4 may be used for the prevention/treatment of NAFLD.

Keywords: C/EBP; NAFLD; cdk4; cyclin D3; hepatic steatosis; p300.

MeSH terms

  • Animals
  • CCAAT-Enhancer-Binding Protein-alpha / metabolism
  • Carcinoma, Hepatocellular / metabolism
  • Carcinoma, Hepatocellular / pathology
  • Cyclin-Dependent Kinase 4 / metabolism*
  • Diet, High-Fat / adverse effects
  • Disease Models, Animal
  • E1A-Associated p300 Protein / metabolism
  • Fatty Liver / metabolism
  • Fatty Liver / pathology
  • Humans
  • Liver / metabolism
  • Liver / pathology
  • Liver Cirrhosis / metabolism
  • Liver Cirrhosis / pathology
  • Liver Neoplasms / metabolism
  • Liver Neoplasms / pathology
  • Male
  • Mice
  • Non-alcoholic Fatty Liver Disease / metabolism*
  • Non-alcoholic Fatty Liver Disease / pathology*
  • Phosphorylation / physiology

Substances

  • CCAAT-Enhancer-Binding Protein-alpha
  • E1A-Associated p300 Protein
  • CDK4 protein, human
  • Cdk4 protein, mouse
  • Cyclin-Dependent Kinase 4