Effects Of Different Exercises On Phenotypic Transformation Of Aortic Smooth Muscle In Diabetic Rats

Objective: To study the function of endurance and resistance exercise in the regulation of aortic smooth muscle cell phenotypic modulation and possible mechanisms in T2 DM rat.Methods: Male SD rats were randomly divided into normal diet Group(pC)and high sugar and fat diet Group(pD),after 7 weeks,Streptozotocin were injected into all rats in pD,after 72 hours the ones whose NFBG? 16.7mmol/L and insulin resistance were selected into the diabetic group.Since then,pC were divided into control group(C),and control+aerobic training group(CA)and control+resistance training group(CR),diabetes group were divided into diabetes group(D),diabetes+ aerobic training group(DA),and diabetes+resistance training group(DR).CA,DA's exercise method is non-weight-bearing treadmill while CR,DR's is weight-bearing ladder training,5 days per week,8 weeks totally.After training for 8 weeks,the expression of FBG,TG,LDL,?-SM-actin,SM-MHC,SM22?,Myocardin,SRF,KLF4 in all groups were tested,tissue changes in aortic smooth muscle were observed by HE and Masson staning.Results: 1.26 of 36 meet diabetes standard in pD,and alloxan was 72.2%.2.After diabetes for 8 weeks,comparing with C,we found that smooth muscle cell disordered,collagen volume scores(CVF)rose significantly,mean carotis artery pressure(MCP)rose significantly,fasting blood glucose(FBG),and insulin resistance index(HOMA-IRI),and triglyceride(TG),and low density lipoprotein(LDL),rose significantly,insulin(FINS)significantly declined,Alpha-SM-actin,SM-MHC,SM22 alpha,and Myocardin and SRF decreased significantly,KLF4 increased significantly in D.3.After exercise for 8 weeks,comparing with D,we found that CVF and MCP goes down,FBG,TG,LDL decressed significantly,FINS rose significantly,Alpha-SM-actin,SM-MHC,SM22 alpha,and Myocardin and SRF increased significantly,KLF4 declined in DA;CVF slightly declined,FBG,TG,LDL decressed significantly,FINS increased significantly,?-SM-actin,SM22?,Myocardin slightly increased.Comepared with DA,DR is better than DA in FBG controlling and IR improving but other index not good than DA.Conclusion:1.After diabetes for 8weeks,rats' pressure became higher,collagen deposited in aorta,SMCs phenotypic modulation.2.Areobic or resistance training can decrease blood sugar and fat,improve IR,decrease collagen and reduce phenotypic modulation.Areobic trainingis better than resistance training in blood fat,pressure and decreasing phenotypic modulation while resistance training is better than areobic training in blood sugar and improving IR.3.The regulation of phenotypic modulation maybe different because of Myocardin.