Apocynin, an Inhibitor of the Nadph Oxidase Complex

Abstract

Apocynin is a phenolic compound isolated from the plant Picrorhiza kurroa Royle ex Benth. Such a compound has been extensively investigated for its therapeutic potential in diseases involving inflammatory processes or oxidative stress due to its ability to inhibit the NADPH oxidase multienzyme complex. This complex consists of two transmembrane proteins (Nox2 and p22phox) and four cytosolic regulatory proteins (p67phox, p47phox, p40phox, and GTPase-Rac) and their activation occurs after the stimulation of phagocytic cells by the mediation of the enzyme myeloperoxidase (MPO). NADPH oxidase is the only enzyme complex that is intended for the production of superoxide anion that is precursor of highly oxidizing substances classified as reactive oxygen species (ROS). NADPH oxidase is an enzyme complex that produces superoxide anion from molecular oxygen. Ta the same time, the superoxide anion is a precursor to reactive oxygen species (ROS) catalyzed by enzymes.These oxidative species, when in excess, can induce burst, causing irreparable tissue damage. They can act by modifying the redox state of DNA, protein or lipid molecules, playing a central role in the development of chronic pathologies and various health complications. One can cite vascular problems, hyperglycemia, diabetes, hypertension, Alzheimer's disease, and cancer, among others. Apocynin, previously activated by MPO, blocks the enzyme complex and prevents the formation of these oxidative species. Therefore, the central biological function of compound is to modulate the action of NADPH oxidase, promoting a positive effect in the prevention/remediation of inflammatory diseases.