NOX4 and acute myocardial infarction: Intravenous administration of a miR-146a mimic after an acute myocardial infarction improves cardiac performance, reduces scar volume, and preserves viable myocardial tissue These effects are mediated, in part, through the regulation of NADPH Oxidase 4 (NOX4) and the induction of endothelial nitric oxide synthase (eNOS) expression [72,73].