The family of mitochondrial uncoupling proteins has been recently recognized as being important in the regulation of mitochondrial function and ROS production.39 In the mammalian heart, ucp2 and ucp3 are the predominant ucp isoforms,16 and there is substantial literature supporting the protective effect of these ucps in ischemia–reperfusion injury.40–41 Indeed, overexpression of UCPs decreases ROS production, improves CM survival and contractile function in the setting of ischemia–reperfusion. This evidence concerns the gene UCP3 and ischemia.