Apolipoprotein A-I expression suppresses COX-2 expression by reducing reactive oxygen species in hepatocytes

Biochem Biophys Res Commun. 2014 Nov 21;454(3):359-63. doi: 10.1016/j.bbrc.2014.10.094. Epub 2014 Oct 24.

Abstract

Abnormal lipid metabolism may contribute to the increase of reactive oxygen species (ROS) and inflammation in the pathogenesis of non-alcoholic steatohepatitis (NASH). Apolipoprotein A-I (apoA-I) accepts cellular cholesterol and phospholipids transported by ATP-binding cassette transporter A1 to generate nascent high density lipoprotein particles. Previous studies revealed that the overexpression of ABCA1 or apoA-I alleviated hepatic lipid levels by modifying lipid transport. Here, we examined the effect of apoA-I overexpression on ROS and genes involved in inflammation in both BEL-7402 hepatocytes and mice. Human apoA-I was overexpressed by transfection in BEL-7402 hepatocytes and by an adenoviral vector in C57BL/6J mice fed a methionine choline-deficient diet. The overexpression of apoA-I in both models resulted in decreased ROS and lipid peroxidation levels, as well as a reduced MAPK phosphorylation and decreased expression levels of c-Fos and COX-2. These results suggest that apoA-I overexpression can reduce steatosis by decreasing ROS levels and suppressing COX-2-induced inflammation in hepatocytes. MAPK and c-Fos are involved in this regulatory process.

Keywords: Apolipoprotein A-I; Non-alcoholic steatohepatitis; Reactive oxygen species.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apolipoprotein A-I / genetics*
  • Apolipoprotein A-I / metabolism
  • Cell Line
  • Cyclooxygenase 2 / genetics*
  • Cyclooxygenase 2 / metabolism
  • Down-Regulation*
  • Hepatocytes / metabolism*
  • Humans
  • Lipid Peroxidation
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Non-alcoholic Fatty Liver Disease / genetics
  • Non-alcoholic Fatty Liver Disease / metabolism
  • Reactive Oxygen Species / metabolism*
  • Up-Regulation*

Substances

  • Apolipoprotein A-I
  • Reactive Oxygen Species
  • Cyclooxygenase 2