Broad Suppression of NADPH Oxidase Activity Exacerbates Ischemia/Reperfusion Injury Through Inadvertent Downregulation of Hypoxia-inducible Factor-1α and Upregulation of Peroxisome Proliferator–activated Receptor-α

Abstract

Both Nox2 and Nox4 contribute to the increase in reactive oxidative species and injury by I/R. However, low levels of reactive oxidative species produced by either Nox2 or Nox4 regulate hypoxia-inducible factor-1α and peroxisome proliferator-activated receptor-α, thereby protecting the heart against I/R, suggesting that Noxs also act as a physiological sensor for myocardial adaptation.