The Effects Of Aerobic Exercise And Dietary Control On Carbohydrate Metabolism In Skeletal Muscle In Type 2 Diabetic Rats

Objective:To investigate the effects of aerobic exercise and dietary control on carbohydrate metabolism in skeletal muscle in type 2 diabetic rats. Methods: 8 rats were randomly selected rats as normal control group(Control,C)from 62 6- week-old male SD rats,fed a standard normal diet. The remaining 54 SD rats which were feed high-fat and carbohydrate diet were injected low-dose streptozotocin though abdominal cavity to establish animal models of type 2 diabetes. And then the type 2 diabetes rats were randomly divided into 4 groups:DM control group(n=9),DM+ aerobic exercise training group(DME,n=10),DM+ Diet control group(DMD,n=10),DM+ aerobic exercise training + Diet control group(DMED,n=10). The DM group's rats continued to feed high-fat and high-carbohydrate diet and did not exercise training;Exercise were used 60 minutes'unloaded swimming for 13 weeks,6 times a week;The dietary control used the same amount of the standard diet in the DM group. 13 weeks later,FPG,FINS,muscle glycogen content, HK, PK,SDH activity were examined in each group of rats. Results:①After 13 weeks of the establishment of type 2 diabetes model,compared with C group,the FPG contents increased significantly in DM group(P<0.01),the FINS contents decreased significantly;Through the double factor variance analysis,aerobic exercise could lower FPG levels in diabetic rats(P<0.05),FINS levels of diabetic rats further increased,but no significant interaction(P>0.05),and the effect of dietary control on FPG levels in diabetic rats did not significantly(P>0.05),But can significantly increase the FINS level of diabetic rats(P <0.05); exercise joint dietary control did not display an obvious interaction on lowering FPG and FINS level in diabetic tats(P>0.05).②After 13 weeks of the establishment of type 2 diabetes model,compared with C group,muscle glycogen content in DM rats was significantly decreased (P<0.05). HK,PK,SDH activity in DM rats were decreased,there were significant differences (P<0.05).③After 13 weeks of the establishment of type 2 diabetes model,compared with C group,muscle glycogen content,HK,PK,SDH activity in DME rats were significantly increased,there was significant differences(P<0.05)by two-factor analysis of variance.④After 13 weeks of the establishment of type 2 diabetes model,compared with C group,glycogen synthesis,HK,PK,SDH activity in DMD group increased,but there were no significant difference(sP>0.05)by two-factor analysis of variance.⑤After 13 weeks of the establishment of type 2 diabetes model,compared with C group,muscle glycogen content and HK, PK activity in DMED rats further increased, but there was no significant interaction(P>0.05)by two-factor analysis of variance. The SDH activity was significantly increased,and there was a significant interaction(P<0.05). Conclusion:①Diabetes model in this study is successful. In the treatment of diabetes,relying on dietary control simply could not effectively reduce the FPG. And aerobic exercise training had a very significant role to control the FPG in diabetic rats,on the base of the dietary control,aerobic exercise training was more effective to reduce the fasting plasma glucose levels in diabetic rats.②The disorder of muscle glycogen synthesis,glycolysis and aerobic oxidation in type 2 diabetes were occurred, which resulting in the increase of blood glucose concentrations.③Long-time aerobic exercise training could improve HK,PK,SDH activity in muscle cells of diabetic,promoting muscle glycogen synthesis,and improve glycolysis and aerobic oxidation in skeletal muscle,reducing blood glucose levels to achieve the prevention of type 2 diabetes.④Dietary control alone could not effectively improve HK,PK,SDH activity in skeletal muscle of type 2 diabetes,and improve muscle glycogen synthesis and glycolysis and aerobic glucose oxidation.⑤Aerobic exercise combined with dietary control might not be effective to promote muscle glycogen synthesis and uptake and oxidation use of glucose in skeletal muscle and not to further reduce blood glucose by further improving the HK,PK,SDH activity in skeletal muscle of diabetes.