Allopurinol protects human glomerular endothelial cells from high glucose-induced reactive oxygen species generation, p53 overexpression and endothelial dysfunction

• Published in: International urology and nephrology Vol. 50; no. 1; pp. 179 - 186
• Main Authors: Eleftheriadis, Theodoros, Pissas, Georgios, Antoniadi, Georgia, Liakopoulos, Vassilios, Stefanidis, Ioannis
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.01.2018; Springer Nature B.V
• Subjects: Allopurinol; Allopurinol - pharmacology; Cell adhesion; Cell Survival - drug effects; Cells, Cultured; Chemiluminescence; Diabetes; Diabetes mellitus; Diabetic nephropathy; DNA damage; Endothelial cells; Endothelial Cells - metabolism; Endothelial Cells - physiology; Free Radical Scavengers - pharmacology; Glucose; Glucose - pharmacology; Humans; Intercellular adhesion molecule 1; Intercellular Adhesion Molecule-1 - metabolism; Kidney Glomerulus - cytology; Medicine; Medicine & Public Health; Mitochondria; Nephrology; Nephrology - Original Paper; Nephropathy; Nitric oxide; Nitric Oxide Synthase - metabolism; Nitric-oxide synthase; p53 Protein; Primary Cell Culture; Reactive oxygen species; Reactive Oxygen Species - metabolism; Tumor Suppressor Protein p53 - metabolism; Urology; Western blotting; Xanthine oxidase; Endothelial dysfunction; Xanthine oxidase; Diabetic nephropathy; Reactive oxygen species; Allopurinol; p53
• ISSN: 0301-1623; 1573-2584
• DOI: 10.1007/s11255-017-1733-5

Purpose Mitochondrial reactive oxygen species (ROS) overproduction in capillary endothelial cells is a prerequisite for the development of diabetic nephropathy. Inhibition of xanthine oxidase, another ROS generator, ameliorates experimental diabetic nephropathy. To test the hypothesis that the initial high glucose-induced ROS production by the mitochondria activates xanthine oxidase, which afterward remains as the major source of ROS, we cultured primary human glomerular endothelial cells (GEnC) under normal or high-glucose conditions, with or without the xanthine oxidase inhibitor allopurinol. Methods ROS generation and nitric oxide synthase (NOS) activity were assessed by chemiluminescence or colorimetrically. Levels of intercellular adhesion molecule 1 (ICAM-1), p53 and phosphorylated p53 (p-p53) were assessed by western blotting. Results Allopurinol prevented high glucose-induced ROS generation indicating that xanthine oxidase is the major source of ROS. Allopurinol protected GEnC from endothelial dysfunction since it prevented the high glucose-induced decrease in NOS activity and increase in ICAM-1 expression. Allopurinol reduced p53 and p-p53 levels induced by high glucose suggesting an axis of xanthine oxidase-derived ROS, DNA damage, p53 stabilization and endothelial dysfunction that may contribute to the pathogenesis of diabetic nephropathy. Conclusions Allopurinol protects GEnC from high glucose-induced ROS generation, p53 overexpression and endothelial dysfunction. These data provide a pathogenetic mechanism that supports the results of experimental and clinical studies about the beneficial effect of xanthine oxidase inhibitors on the development of diabetic nephropathy.