Effect of progressive aerobic training, injection of adipose tissue-derived stem cells, and their combination on Bax and Bcl-2 levels of beta - pancreatic cells in diabetic rats

Introduction: Apoptosis is protective cellular process the plays an important role in the development and homeostasis of natural tissue as well as disease-causing factors. Current study was accomplished in order to determine the effect of progressive aerobic training with injection of adipose tissue-derived stem cells Bax (as an apoptotic protein) and Bcl-2 (as an anti-apoptotic protein) and the ratio of Bax to Bcl-2 of beta-pancreatic cells in diabetic rats with streptozotocin. Materials and Methods: 48 rat’s adult rats were divided into 6 groups: control, sham, diabetes, exercise, stem cell and exercise +stem cell. Diabetes was induced by intraperitoneal injection of streptozotocin (60 mg/kg) dissolved in citrate buffer, with pH = 4.5. The exercise protocol was treadmill running for 5 days per week with intensity of 60-70% VO2max for 6 weeks. In the stem cell group, 5 ml PBS with 1.5 ×106 stem cells extracted from human adipose tissue of diabetic rats was injected into the tail vein. Levels of Bax and Bcl2 of beta pancreatic cells were measured by laboratory kit. Results: The findings showed that the levels of Bax and Bcl- 2 significanly increased and decreased in the diabetic grop than the control group, respectively (P< 0. 000).  Bax/Bcl-2 ratio also increased in the diabetic group than the control group. The diabetic groups treated with exercise, stem cells, and both exhibited signifiacly lower Bax and higher Bcl-2 levels than the diabetic group alone.  Moreover, in these groups Bax/Bcl-2 ratio was sigficanly lower than the diabetic group alone. Conclusion: It seems that exercise, stem - cell therapy and the combined treatement could prevent β-cell apoptosis.