Expression of NADPH oxidase in human pancreatic islets

Abstract Aims NADPH oxidase (NOX) is a known source of superoxide anions in phagocytic and non-phagocytic cells. In this study, the presence of this enzyme in human pancreatic islets and the importance of NADPH oxidase in human β-cell function were investigated. Main methods and key findings In isolated human pancreatic islets, the expression of NADPH oxidase components was evidenced by real-time PCR (p22 PHOX , p47 PHOX and p67 PHOX ), Western blotting (p47 PHOX and p67 PHOX ) and immunohistochemistry (p47 PHOX , p67 PHOX and gp91 PHOX ). Immunohistochemistry experiments showed co-localization of p47 PHOX , p67 PHOX and gp91 PHOX (isoform 2 of NADPH oxidase—NOX2) with insulin secreting cells. Inhibition of NADPH oxidase activity impaired glucose metabolism and glucose-stimulated insulin secretion. Significance These findings demonstrate the presence of the main intrinsic components of NADPH oxidase comprising the NOX2 isoform in human pancreatic islets, whose activity also contributes to human β-cell function.