TRIB2-Mediated Modulation of AMPK Promotes Hepatic Insulin Resistance

Diabetes. 2024 Aug 1;73(8):1199-1214. doi: 10.2337/db23-0195.

Abstract

Insulin resistance and its linked health complications are increasing in prevalence. Recent work has caused the role of Tribbles2 (TRIB2) in metabolism and cellular signaling to be increasingly appreciated, but its role in the progression of insulin resistance has not been elucidated. Here, we explore the functions of TRIB2 in modulating insulin resistance and the mechanism involved in insulin-resistant mice and palmitic acid-treated HepG2 cells. We demonstrate that whole-body knockout and hepatic-specific TRIB2 deficiency protect against diet-induced insulin resistance, inflammation, and endoplasmic reticulum stress. Accordingly, upregulation of TRIB2 in the liver aggravates these metabolic disturbances in high-fat diet-induced mice and ob/ob mice. Mechanistically, TRIB2 directly binds to the αγ-SBS domain of PRKAB through its pseudokinase domain, subsequently inhibiting the formation and activity of the AMPK complex. Moreover, the results of intervention against AMPK suggest that the effects of TRIB2 depend on AMPK. Our findings reveal that TRIB2 is a novel target for the treatment of insulin resistance and its associated metabolic complications and clarify the function of TRIB2 as a regulatory component of AMPK activity.

MeSH terms

  • AMP-Activated Protein Kinases* / genetics
  • AMP-Activated Protein Kinases* / metabolism
  • Animals
  • Calcium-Calmodulin-Dependent Protein Kinases
  • Diet, High-Fat* / adverse effects
  • Endoplasmic Reticulum Stress / drug effects
  • Endoplasmic Reticulum Stress / physiology
  • Hep G2 Cells
  • Humans
  • Insulin Resistance* / genetics
  • Insulin Resistance* / physiology
  • Intracellular Signaling Peptides and Proteins / genetics
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Liver* / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout*
  • Protein Serine-Threonine Kinases / antagonists & inhibitors
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism

Substances

  • AMP-Activated Protein Kinases
  • Protein Serine-Threonine Kinases
  • tribbles 2 protein, mouse
  • Intracellular Signaling Peptides and Proteins
  • TRIB2 protein, human
  • Calcium-Calmodulin-Dependent Protein Kinases