The Effect of Regular Swimming Exercise on the Levels of Renal Matrix Mettaloproteinase-2 and Transforming Growth Factor-β1 in Rats with Diabetes

Background & Aims: Numerous studies have reported the renoprotective effects of exercise in both human and animal models of diabetic nephropathy. However, detailed mechanism of action by which exercise has a favorable influence on renal fibrogenic factors is not yet fully understood. Therefore, the aim of this study was to assess the effect of swimming exercise on the activity of renal matrix mettaloproteinase-2 (MMP-2) and transforming growth factor-β1 (TGF- β1) in rats with diabetes. Methods: The study sample consisted of 28 male Wistar rats that were randomly divided into 4 groups (7 rats per group) of control, diabetes, exercise, and diabetes-exercise. Diabetes was induced through an intraperitoneal injection of alloxan (90 mg/kg) in rats. The animals received swimming exercise for 6-30 minutes per day, 5 days a week for 8 weeks. The rats were sacrificed 72 hours after the last treatments and renal MMP-2 activity and TGF- β1 level were evaluated by Zymography and ELIZA (enzyme-linked immunosorbent assay) method. Data were analyzed using one-way analysis of variance. Results: Diabetes induction significantly increased renal TGF-β1 (P < 0.001) and decreased MMP-2 activity (P < 0.001) compared with the control group. Furthermore, 8 weeks of swimming exercise was associated with a significant decrease in renal TGF-β1 level (P = 0.001) and elevated MMP-2 activity (P = 0.001) in rats in the diabetes-exercise group. Conclusion: It seems that the renoprotective effects of regular swimming exercise against diabetes-induced kidney damage may be partly mediated via the up-regulation of renal MMP-2 activity and reduction of TGF-β1 level in diabetic renal tissue.