AMP-activated protein kinase α2 protects against liver injury from metastasized tumors via reduced glucose deprivation-induced oxidative stress

J Biol Chem. 2014 Mar 28;289(13):9449-59. doi: 10.1074/jbc.M113.543447. Epub 2014 Feb 10.

Abstract

It is well known that tumors damage affected tissues; however, the specific mechanism underlying such damage remains elusive. AMP-activated protein kinase (AMPK) senses energetic changes and regulates glucose metabolism. In this study, we examined the mechanisms by which AMPK promotes metabolic adaptation in the tumor-bearing liver using a murine model of colon cancer liver metastasis. Knock-out of AMPK α2 significantly enhanced tumor-induced glucose deprivation in the liver and increased the extent of liver injury and hepatocyte death. Mechanistically, we observed that AMPK α2 deficiency resulted in elevated reactive oxygen species, reduced mitophagy, and increased cell death in response to tumors or glucose deprivation in vitro. These results imply that AMPK α2 is essential for attenuation of liver injury during tumor metastasis via hepatic glucose deprivation and mitophagy-mediated inhibition of reactive oxygen species production. Therefore, AMPK α2 might represent an important therapeutic target for colon cancer metastasis-induced liver injury.

Keywords: AMP-activated kinase (AMPK); Glucose; Metastasis; Oxidative Stress; Tumor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AMP-Activated Protein Kinases / deficiency
  • AMP-Activated Protein Kinases / genetics
  • AMP-Activated Protein Kinases / metabolism*
  • Animals
  • Cell Line, Tumor
  • Colonic Neoplasms / pathology
  • Energy Metabolism
  • Gene Knockout Techniques
  • Glucose / deficiency*
  • Hepatocytes / cytology
  • Hepatocytes / metabolism
  • Hepatocytes / pathology
  • Humans
  • Liver / injuries*
  • Liver / metabolism*
  • Liver / pathology
  • Liver Neoplasms / metabolism*
  • Liver Neoplasms / pathology
  • Liver Neoplasms / secondary*
  • Mice
  • Mitophagy
  • Necrosis / metabolism
  • Oxidative Stress*
  • Reactive Oxygen Species / metabolism

Substances

  • Reactive Oxygen Species
  • AMP-Activated Protein Kinases
  • Glucose