Effect of Aerobic Exercise Intervention on Renal Insulin Signaling Pathway in db/db Mice

Abstract

Objective: To study the effects on insulin signaling pathway in db/db mice during aerobic exercise and discuss the related mechanisms. Methods: Ten BKS mice were selected as the quiet control group (WT group), and 20 BKS-db/db mice were randomly divided into two groups as the diabetic quiet control group (C group) and the diabetic simple exercise group (E group), with 10 mice in each group. The mice in E group were acclimatized to the low-intensity criterion (2~7m/min, 10min/day, 5 days/week) for one week, and then subjected to 8 weeks of aerobic endurance exercise training on a running platform (0° incline, 7~12m/min, 30~40min/day, 5 days/week), while the mice in groups WT and C were kept quietly. At the end of the experiment, the fasting blood glucose content, glucose tolerance, insulin tolerance of each group of mice were detected respectively, and the expression levels of AKT protein and insulin receptor protein were detected by Western Blot technique. Results: (1) Compared with the diabetic quiet control group (Group C), the glucose tolerance and insulin tolerance in the quiet control group (Group WT) showed significant changes (P＜0.05); in the diabetic simple exercise group (Group E), there was no significant change in glucose tolerance and insulin tolerance (P＞0.05). (2) Compared with the diabetic quiet control group (Group C), the expression level of insulin receptor protein was down-regulated (P<0.05) and AKT protein expression was up-regulated (P<0.05) in the diabetic simple exercise group (Group E); compared with the quiet control group (Group WT), the expression level of insulin receptor protein was increased (P<0.05) and AKT protein was decreased (P<0.05) in the diabetic quiet control group (Group C), expression level decreased (P<0.05). Conclusion: Exercise alone could not improve insulin resistance in db/db mice; eight weeks of aerobic exercise improved and corrected renal insulin signaling pathway and alleviated renal insulin resistance in db/db mice.