Preventive effect of exercise training on diabetic kidney disease in ovariectomized rats with type 1 diabetes

Abstract

This study evaluated the effects of moderate regular physical exercise on lipid peroxidation, inflammation and renal function and structure in streptozotocin (STZ)-induced ovariectomized diabetic rats. Twenty-four Wistar rats were anesthetized and submitted to bilateral ovariectomy. The rats were divided into four experimental groups: ovariectomized control (OC), ovariectomized trained control (OTC), ovariectomized diabetic (OD), ovariectomized trained diabetic (OTD). The OTD and OTC groups were submitted to treadmill running for four weeks before to diabetes mellitus (DM) induction with STZ (40 mg/kg, i.v) or vehicle injection, respectively, and continued the training for another eight weeks after the injections. Urine samples were collected 24 h after the last training session, and blood samples and kidneys were collected after euthanasia. Our results showed that physical exercise attenuated the loss of body weight and postprandial glucose and improved physical capacity in the OTD group. Lower serum creatinine levels, glycosuria, and proteinuria were also observed in this group. There was no difference in 17β-estradiol levels between the experimental groups. The glomerular and tubulointerstitial changes were attenuated in the OTD group. Expressions of macrophages, lymphocytes, fibronectin, TGF-β1, and NF-κB were reduced in the glomeruli of OTD group. Exercise also reduced macrophages, lymphocytes, and TGF-β1 expression in the tubulointerstitial compartment of the renal cortex of this group. In addition, increased levels of TBARS in the renal cortex of diabetic rats were prevented by exercise in the OTD group. In conclusion, our study shows that physical exercise exerted a renoprotective effect against the progression of diabetic kidney disease in ovariectomized rats. Impact statement To date, no studies have been found evaluating the effects of physical exercise on renal function and structure changes in ovariectomized rats with type 1 diabetes. Therefore, this work emerges with an important tool for strengthening and expanding innovative research on exercise with potential for the prevention of renal diseases in ovariectomized diabetic rats, and future development of studies that seek to increase scientific knowledge about the beneficial effects of physical exercise on renal diseases in humans.