High fat diet-induced downregulation of TRPV2 mediates hepatic steatosis via p21 signalling

J Physiol Biochem. 2024 Feb;80(1):113-126. doi: 10.1007/s13105-023-00988-8. Epub 2023 Oct 26.

Abstract

The global prevalence and incidence of non-alcoholic fatty liver disease (NAFLD) are exhibiting an increasing trend. NAFLD is characterized by a significant accumulation of lipids, though its underlying mechanism is still unknown. Here we report that high-fat diet (HFD) feeding induced hepatic steatosis in mice, which was accompanied by a reduction in the expression and function of hepatic TRPV2. Moreover, conditional knockout of TRPV2 in hepatocytes exacerbated HFD-induced hepatic steatosis. In an in vitro model of NAFLD, TRPV2 regulated lipid accumulation in HepG2 cells, and TRPV2 activation inhibited the expression of the cellular senescence markers p21 and p16, all of which were mediated by AMPK phosphorylation. Finally, we found that administration of probenecid, a TRPV2 agonist, impaired HFD-induced hepatic steatosis and suppressed HFD-induced elevation in p21 and p16. Collectively, our findings imply that hepatic TRPV2 protects against the accumulation of lipids by modulating p21 signalling.

Keywords: Fatty liver; Hepatic steatosis; Lipid accumulation; TRPV2; p21.

MeSH terms

  • Animals
  • Calcium Channels* / genetics
  • Calcium Channels* / metabolism
  • Cyclin-Dependent Kinase Inhibitor p21 / metabolism
  • Diet, High-Fat* / adverse effects
  • Down-Regulation
  • Hepatocytes / metabolism
  • Lipid Metabolism
  • Lipids
  • Liver / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Non-alcoholic Fatty Liver Disease* / etiology
  • Non-alcoholic Fatty Liver Disease* / metabolism
  • TRPV Cation Channels* / genetics
  • TRPV Cation Channels* / metabolism

Substances

  • Lipids
  • Trpv2 protein, mouse
  • TRPV Cation Channels
  • Calcium Channels
  • Cdkn1a protein, mouse
  • Cyclin-Dependent Kinase Inhibitor p21