[NADPH oxidase--a specialized enzyme complex for the formation of active oxygen metabolites]

Generation of reactive oxygen species (ROS) by phagocytes play an important role in defence against infection. For this purpose, phagocytes possess superoxide-forming enzyme NADPH oxidase. NADPH oxidase is a complex, multicomponent enzymatic system which is assembled in plasma membrane upon activation. In recent years, it has been evident that other cells and tissues can also produce small amounts of ROS by NADPH oxidase-like enzyme. The growing list includes B-lymphocytes, fibroblasts, kidney mesangial cells, endothelial cells, osteoclasts. The physiological and pathophysiological relevance of this extra-phagocytic superoxide production has only recently begun to be addressed. Evidence is emerging that generation of ROS might be important factor in triggering variety of cellular functions (cell growth, development, locomotion). Here, we review numerous literature data concerning the structure, regulation and mechanisms of activation of NADPH oxidase of phagocytes and other mammalian cells.