NADPH Oxidase in Tissue Repair and Regeneration 110

Redox homeostasis is a delicate balance maintaining physiological signaling functions of free radicals as well as antioxidant capacity to prevent excess free radical overflow. Disturbance of this redox equilibrium creating oxidative stress can result in cell injury, and this underlies the pathogenesis of many cardiovascular diseases such as myocardial ischemia and reperfusion injury, hypertension, atherosclerosis, brain damage after stroke and traumatic brain injury, as well as loss of vision due to degeneration in the retina. Free radicals such as superoxide and hydrogen peroxide when produced intracellularly at low concentration, can also act as second messengers through redox signaling to regulate physiological processes such as wound healing, angiogenesis, and differentiation of stem cells. Of all the redox enzymes, NADPH oxidase is the only one whose sole function is production of reactive oxygen species (ROS) and appears to have a significant role in modulating tissue repair and regeneration. The shortage of donors for transplantation surgery to treat life-threatening conditions such as lung and heart failure has driven the search for alternative therapeutic strategies. Exploiting the intrinsic regenerative potential of tissues by manipulating cellular mechanisms involved in tissue repair and growth is an attractive and clinically translatable therapeutic strategy to treat late-stage diseases and severe tissue injury. Here we provide a brief overview of the role of NADPH oxidases in regenerative medicine.