Mitochondrial GCN5L1 regulates cytosolic redox state and hepatic gluconeogenesis via glycerol phosphate shuttle GPD2

Biochem Biophys Res Commun. 2022 Sep 17:621:1-7. doi: 10.1016/j.bbrc.2022.06.092. Epub 2022 Jun 28.

Abstract

Hepatic gluconeogenesis is crucial for maintaining blood glucose during starvation, and a major contributor for hyperglycemia. Cellular redox state is related to mitochondrial biology and regulates conversion of specific metabolites to glucose. General control of amino acid synthesis 5 (GCN5) like-1 (GCN5L1) is a mitochondria-enriched protein which modulates glucose and amino acid metabolism. Here we show a new regulatory mode of GCN5L1 on gluconeogenesis using lactate and glycerol. We observed GCN5L1 deletion dramatically inhibited glucose production derived from glycerol and lactate, due to increased cytosolic redox state. The underlying mechanism is that GCN5L1 directly binds to the key component of mitochondrial shuttle glycerol phosphate dehydrogenase 2 (GPD2) and modulates its activity. These results have significant implications for understanding the physiological role and regulatory mechanism of mitochondrial shuttle in diabetes development and provide a novel therapeutic potential for diabetes.

Keywords: Cytosolic redox state; GCN5L1; Gluconeogenesis; Glycerol-3-phosphate dehydrogenase 2; Mitochondrial redox state.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / metabolism
  • Gluconeogenesis*
  • Glucose / metabolism
  • Glycerol / metabolism
  • Glycerolphosphate Dehydrogenase* / genetics
  • Glycerolphosphate Dehydrogenase* / metabolism
  • Lactic Acid / metabolism
  • Mitochondria / metabolism
  • Oxidation-Reduction
  • Phosphates / metabolism

Substances

  • Amino Acids
  • Phosphates
  • Lactic Acid
  • Glycerolphosphate Dehydrogenase
  • Glucose
  • Glycerol