Effects of Exercise and Stevia on Renal Ischemia/reperfusion Injury in Rats.

Background. The present work was designed to study the effects of methanolic stevia extracts and aerobic exercise and combination of both on renal ER injury in male rats. Methods. 60 adult male Sprague-Dawley rats were subdivided into five equal groups as sham, control, exercise, stevia, and stevia plus exercise group. After 5 weeks of exercise and stevia, animals were exposed to 45 min of left renal ischemia and right nephrectomy followed by reperfusion. Serum creatinine, creatinine clearance, fractional Na excretion (FENa+), malondialdehyde (MDA), reduced glutathione (GSH) and catalase (CAT) levels in kidney tissues were measured. Also, renal histopathology and the expression of caspase-3 by immunohistochemical examination were done. Results. The results showed that stevia, exercise or combination of stevia and exercise caused a significant decrease in serum level of creatinine (p < 0.001) and FENa+ (p < 0.001) and an increase in creatinine clearance (p < 0.001). Moreover, this caused a significant decrease in (MDA, p < 0.046) and an increase in GSH (p < 0.01) and CAT (p < 0.01), as well as causing a significant decrease in caspase 3 expression compared to the control group. Conclusion. Pretreatment with either stevia or exercise of combination of both seem to have protective effects on renal ER injury. However, the protective effect of exercise against renal ER injury seems to be less than stevia. These effects might be due to attenuation of oxidative stress and apoptosis in kidney tissues.