AMPKα2 deficiency exacerbates long-term PM2.5 exposure-induced lung injury and cardiac dysfunction

Free Radic Biol Med. 2018 Jun:121:202-214. doi: 10.1016/j.freeradbiomed.2018.05.008. Epub 2018 May 10.

Abstract

Previous studies have demonstrated that long-term exposure to fine particulate matter (PM2.5) increases the risk of respiratory and cardiovascular diseases. As a metabolic sensor, AMP-activated protein kinase (AMPK) is a promising target for cardiovascular disease. However, the impact of AMPK on the adverse health effects of PM2.5 has not been investigated. In this study, we exposed wild-type (WT) and AMPKα2-/- mice to either airborne PM2.5 (mean daily concentration ~64 µg/m3) or filtered air for 6 months through a whole-body exposure system. After exposure, AMPKα2-/- mice developed severe lung injury and left ventricular dysfunction. In the PM2.5-exposed lungs and hearts, loss of AMPKα2 resulted in higher levels of fibrotic genes, more collagen deposition, lower levels of peroxiredoxin 5 (Prdx5), and greater induction of oxidative stress and inflammation than observed in the lungs and hearts of WT mice. In PM2.5-exposed BEAS-2B and H9C2 cells, inhibition of AMPK activity significantly decreased cell viability and Prdx5 expression, and increased the intracellular ROS and p-NF-κB levels. Collectively, our results provide the first direct evidence that AMPK has a marked protective effect on the adverse health effects induced by long-term PM2.5 exposure. Our findings suggest that strategies to increase AMPK activity may provide a novel approach to attenuate air pollution associated disease.

Keywords: AMPK; Heart failure; Lung injury; PM(2.5); Prdx5.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AMP-Activated Protein Kinases / physiology*
  • Air Pollutants / adverse effects*
  • Animals
  • Bronchi / cytology
  • Bronchi / physiology
  • Cells, Cultured
  • Heart Diseases / enzymology
  • Heart Diseases / etiology
  • Heart Diseases / pathology
  • Heart Diseases / prevention & control*
  • Humans
  • Lung Injury / enzymology
  • Lung Injury / etiology
  • Lung Injury / pathology
  • Lung Injury / prevention & control*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Myocytes, Cardiac / cytology
  • Myocytes, Cardiac / physiology
  • Oxidative Stress*
  • Particulate Matter / adverse effects*
  • Rats

Substances

  • Air Pollutants
  • Particulate Matter
  • AMPK alpha2 subunit, mouse
  • AMP-Activated Protein Kinases