Thrap3 promotes nonalcoholic fatty liver disease by suppressing AMPK-mediated autophagy

Exp Mol Med. 2023 Aug;55(8):1720-1733. doi: 10.1038/s12276-023-01047-4. Epub 2023 Aug 1.

Abstract

Autophagy functions in cellular quality control and metabolic regulation. Dysregulation of autophagy is one of the major pathogenic factors contributing to the progression of nonalcoholic fatty liver disease (NAFLD). Autophagy is involved in the breakdown of intracellular lipids and the maintenance of healthy mitochondria in NAFLD. However, the mechanisms underlying autophagy dysregulation in NAFLD remain unclear. Here, we demonstrate that the hepatic expression level of Thrap3 was significantly increased in NAFLD conditions. Liver-specific Thrap3 knockout improved lipid accumulation and metabolic properties in a high-fat diet (HFD)-induced NAFLD model. Furthermore, Thrap3 deficiency enhanced autophagy and mitochondrial function. Interestingly, Thrap3 knockout increased the cytosolic translocation of AMPK from the nucleus and enhanced its activation through physical interaction. The translocation of AMPK was regulated by direct binding with AMPK and the C-terminal domain of Thrap3. Our results indicate a role for Thrap3 in NAFLD progression and suggest that Thrap3 is a potential target for NAFLD treatment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AMP-Activated Protein Kinases / metabolism
  • Animals
  • Autophagy / genetics
  • Diet, High-Fat / adverse effects
  • Hep G2 Cells
  • Humans
  • Lipid Metabolism
  • Liver / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mitochondria / metabolism
  • Non-alcoholic Fatty Liver Disease* / metabolism
  • Transcription Factors / metabolism

Substances

  • AMP-Activated Protein Kinases
  • Transcription Factors
  • THRAP3 protein, human
  • Thrap3 protein, mouse