NADPH Oxidase

NADPH-oxidase (NOX) is a highly regulated dynamic complex comprising membrane and cytosolic proteins and is the major source of nonmitochondrial cellular reactive oxygen species (ROS). The ROS generated by NADPH oxidases have crucial roles in various physiological processes, including innate immunity, modulation of redox-dependent signalling cascades, and as cofactors in the production of hormones.

NOX enzymes are a family of transmembrane proteins comprising seven members (NOX1-NOX5 and DUOX1 and DUOX2), each with a specific tissue distribution and activation mechanism. They catalyze the reduction of molecular oxygen to superoxide anion, which in turn reacts quickly to generate other ROS, such as hydrogen peroxide. Although basic NOX activity is crucial for normal physiology, overshooting activity of NOX enzymes leads to disease. NADPH oxidases are increasingly recognized as interesting drug targets.