Alterations of the Kidney Cortex Proteome in Response to Exercise Training in Normoglycemic and Hyperglycemic Conditions

Hyperglycemia induces systemic vascular endothelial dysfunction and renal damage through the overproduction of reactive oxygen species (ROS). Regular aerobic exercise decreases the incidence of ROS-associated diseases and is involved in protection against systemic and renal vascular alterations. To investigate the impact of exercise training on renal protein expression in hyperglycemic conditions, we performed gel-based proteomic analyses of the rabbit kidney cortex from sedentary and exercised rabbits after exposure to normal or high glucose concentrations. Abundance of proteins in the renal cortex was determined by two-dimensional polyacrylamide gel electrophoresis followed by protein identification with mass spectrometry, using peptide mass and fragment fingerprintings. We identified the differential abundance of twenty seven proteins in exercise trained animals among the total of 324 spots, from which five proteins are related to the down-regulation of cellular oxidative stress (albumin, protein disulfide isomerase, heat shock protein 60-like chaperonin, DJ-1 and ubiquinol-cytochrome-c reductase), and three proteins are involved in energy metabolism (short-chain acyl-coenzyme A dehydrogenase, malate dehydrogenase and L-arginine-glycine amidinotransferase). We concluded that exercise training induces an increase in the abundance of five antioxidant proteins in the renal cortex, which could explain the well-known increase in endothelial-dependent vasodilation that results from exercise and the consequential protective effect against increased oxidative stress of the hyperglycemic milieu. Moreover, this protective effect could be important in the prevention of kidney vascular damage associated with diabetes pathophysiology.