Differential contribution of Nox1, Nox2 and Nox4 to kidney vascular oxidative stress and endothelial dysfunction in obesity

Publication date: Available online 20 September 2019Source: Redox BiologyAuthor(s): Mercedes Muñoz, Maria Elvira López-Oliva, Claudia Rodríguez, María Pilar Martínez, Javier Sáenz-Medina, Ana Sánchez, Belén Climent, Sara Benedito, Albino García-Sacristán, Luis Rivera, Medardo Hernández, Dolores PrietoAbstractOxidative stress-associated endothelial dysfunction is a key pathogenic factor underlying the microvascular complications of metabolic disease. NADPH oxidase (Nox) is a major source of oxidative stress in diabetic nephropathy and chronic kidney disease, despite Nox4 and Nox2 have been identified as relevant sources of vasodilator endothelial H2O2.The present study was sought to investigate the role of Nox enzymes in renal vascular oxidative stress and endothelial dysfunction in a rat model of genetic obesity. Endothelial function was assessed in intrarenal arteries of obese Zucker rats (OZR) and their counterparts lean Zucker rats (LZR) mounted in microvascular myographs, and superoxide (O2.-) and H2O2 production were measured. Impaired endothelium-dependent relaxations to acetylcholine (ACh) were associated to augmented O2.- generation, but neither ROS scavengers nor the Nox inhibitor apocynin significantly improved these relaxant responses in renal arteries of OZR. Whereas NO contribution to endothelial relaxations was blunted, catalase-sensitive non-NO non-prostanoid relaxations were enhanced in obese rats. Interestingly, NADPH–dependent O2.- production wa...
Source: Redox Biology - Category: Biology Source Type: research