RAC1 and diabetic cardiomyopathy: Rac1, the cytosolic component of many NADPH oxidase isoforms, is also involved in the pathogenesis of diabetic cardiomyopathy; indeed, the effects of hyperglycemia on mitochondrial ROS production in the heart and myocardial dysfunction are significantly decreased in Rac1-knockout mice treated with streptozotocin [289].