Effect of moderate exercise on renal changes and oxidative stress in ovariectomized rats with type 1 diabetes mellitus

This study evaluated the aerobic exercise effects of moderate and progressive intensity on renal function and structure, and oxidative stress in ovariectomized rats with type 1 diabetes mellitus induced by streptozotocin (STZ). Eighteen Wistar rats were divided into 3 groups: OSC - ovariectomized and sedentary control rats; OSD - ovariectomized and sedentary diabetic rats; and OTD - ovariectomized and trained diabetic rats. After induction of diabetes, the OTD group was submitted to eight weeks of exercise. Twenty-four hours after the last training session urine samples were collected. Blood samples and kidneys were collected after euthanasia for renal function analysis, histology, morphometry and oxidative stress. Our results have shown a reduction of the weight gain, increase of kidney weight and postprandial glycemia in diabetic rats. However, exercise decreased glycosuria and prevented the proteinuria in OTD group rats. Focal segmental glomerulosclerosis (FSGS), juxtamedullary glomerular tuft area, tubulointerstitial lesions (TIL), brush border loss and tubular cell debridement were reduced in OTD rats. In addition, exercise training decreased urinary and plasma concentrations of thiobarbituric acid reactive substance (TBARS). Our results demonstrate the beneficial effect of progressive aerobic exercise on proteinuria, glycosuria, and renal structure in ovariectomized diabetic rats, which may be mediated in part by reduction of oxidative stress.