| Objective: to investigate the protective effect of moderate intensity treadmill exercise on vascular disease in db/db mice and its possible mechanism,so as to provide a reasonable exercise prescription basis for moderate intensity exercise to improve vascular disease in type 2 diabetes mellitus.Methods: db/db mice were randomly divided into 8 diabetes control group(DC group)and 8 diabetes exercise group(DM group).Wild-type mm mice were randomly divided into 8 mice in the normal control group(MC group)and 8 mice in the normal exercise group(mm group).The MM group and the DM group performed platform exercise for 8 weeks.The exercise intensity was set at 10m/min and the slope was 0.Exercise 30 minutes a day,intervention 5 days a week,rest on Monday and Friday.Progressive treadmill exercise was performed for 5 days prior to formal intervention.During the whole experiment,the MC group and the DC group did not exercise intervention.The body weight and fasting blood glucose of each group were monitored weekly,and the heart rate and blood pressure at the early and late stages were measured.8 weeks after treadmill exercise intervention in blood and aortic,using ELISA method to measure the content of serum insulin,by HE and α-SMA staining to observe morphologic changes in mice aorta,using flow cytometry technical analysis to measure the number of circulating endothelial progenitor cells(EPCs),Western blot method to detect the aorta inflammation and apoptosis related proteins expression changes,real time quantitative PCR technique to detect cycle and the expression of aortic miR-126-5p.Research results:1.General indicators Body weight : At week 2 and 8,the weight level of mice in the DC and DM groups was higher than that in the MC group(P < 0.05),and at week 8,the weight level of mice in the DC group was significantly higher than that in the DM group(P < 0.05).After 8 weeks of exercise,the body weight level of each group was higher than the initial body weight(P < 0.01).Blood glucose : after 8 weeks of exercise intervention,blood glucose levels in both MM and DM groups decreased significantly from the initial values(P < 0.05).At week 2 and 8,the blood glucose level of the DC group and the DM group was significantly higher than that of the MC group(P < 0.05),and the blood glucose level of the DM group was lower than that of the DC group at week 8(P < 0.05).Heart rate: after exercise intervention,the heart rate of mice in each exercise group at week 8 was lower than the initial value,and the DM group had statistical significance(P < 0.05).At week 0,the heart rate of the DC group was significantly higher than that of the MC group(P < 0.05).At week 8,the heart rate of DC group was higher than that of MC group and DM group(P < 0.05).Blood pressure : after exercise intervention,the systolic and diastolic blood pressure of each exercise group decreased significantly(P < 0.05).At week 0 and 8,both systolic and diastolic blood pressures in the DC group were significantly higher than those in the MC group(P < 0.01),and both systolic and diastolic blood pressures in the DM group were significantly lower than those in the DC group(P < 0.01).Insulin content: the insulin content of DC group was significantly higher than that of MC group(P < 0.05).After 8 weeks of exercise intervention,the insulin content of DM group was significantly lower than that of DC group(P < 0.05).2.Morphological indicators HE staining results: no significant pathological changes were observed in the aorta of MC and MM groups under light microscope.In the aorta of the DC group,the cells became more stratified,the vascular wall became less elastic,the local intima showed protrusions,the local arrangement of the elastic fibers in the middle membrane was disordered and the layers were obviously twisted,some of the smooth muscle cells were broken,and the smooth muscle cells became a mass distribution.After 8 weeks of exercise intervention,the vascular wall damage in the DM group was significantly reduced,the intimal protrusion was reduced,and the fiber arrangement was more orderly than that in the DC group.The median aortic thickness of the DC group was significantly higher than that of the MC group(P < 0.05),and that of the DM group was significantly lower than that of the DC group(P < 0.05).There was no significant change in film thickness in MC and MM groups.Results of α-SMA immunohistochemical staining: after staining,a small amount of light yellow granules were observed in the DC group,and more brown-yellow granules were observed near the middle membrane in the MC group.Compared with the MC group,the brown-yellow granules were significantly reduced in the DC and DM groups,suggesting that the contractile phenotype of aortic smooth muscle cells was reduced in the diabetic environment.The positive expression of SMA in the DC and DM groups decreased significantly compared with the MC group(P < 0.01),and the positive expression of SMA in the DM group increased significantly compared with the DC group.3.Circular indicators Number of circulating endothelial progenitor cells: compared with MC group,the number of plasma endothelial progenitor cells in DC group decreased significantly(P < 0.01).After exercise,the DM group was significantly higher than the DC group(P < 0.05),and the MM group was significantly higher than the MC group(P < 0.05).After exercise,the correlation between the number of circulating endothelial progenitor cells and circulating mir-126-5p was high(r=0.8327,P < 0.01).After exercise,the number of circulating endothelial progenitor cells was highly correlated with aortic mir-126-5p(r=0.9351,P < 0.01).4.The PCR Results of circulating mir-126-5p: compared with the MC group,the expression of mir-126-5p in the DC group was significantly reduced(P < 0.01).After 8 weeks of exercise intervention,the expression of mir-126-5p in the whole blood of the mice in each exercise group was higher than that in the control group(P < 0.05).Results of aortic mir-126-5p: the expression of DC group was significantly lower than that of MC group(P < 0.05).After 8 weeks of exercise intervention,the expression of mir-126-5p in the aorta of each exercise group was significantly higher than that of the control group(P < 0.05).5.WB indicators of the aorta VCAM-1 protein expression results: compared with MC group,vcam-1 protein expression in DC group was significantly increased(P < 0.01).After 8 weeks of exercise intervention,MM group decreased significantly compared with MC group(P < 0.05);DM group was significantly lower than DC group(P < 0.01).NF-κB protein expression: compared with MC group,NF-κB protein expression in DC mice was significantly increased(P < 0.01).After 8 weeks of exercise intervention,each exercise group significantly decreased compared with the control group(P < 0.01).TRAF7 protein expression results: compared with the MC group,the expression of TRAF7 protein in the DC group significantly increased(P < 0.01).After 8 weeks of exercise intervention,the expression of TRAF7 in the MM group significantly decreased compared with the MC group,and significantly decreased in the DM group compared with the DC group(P < 0.01).Caspase3 expression was significantly increased in the DC group compared with the MC group(P < 0.01).After 8 weeks of exercise intervention,the expression of caspase-3 in MM group significantly decreased compared with that in MC group,and that in DM group significantly decreased compared with that in DC group(P < 0.01).Bcl-2 protein expression results: compared with MC group,the protein expression of DC group was significantly decreased(P < 0.01).After 8 weeks of exercise intervention,the expression of bcl-2 protein in each exercise intervention group was significantly higher than that in the control group(P < 0.01).Bax protein expression results: compared with the MC group,Bax protein expression in the DC group significantly increased(P < 0.01),and Bax protein expression in the exercise intervention group was lower than that in the control group after 8 weeks of exercise(P < 0.01).Results: the Bcl-2 /Bax ratio of the DC group was significantly higher than that of the MC group(P<0.01).After exercise intervention,the ratio of the exercise group was significantly higher than that of the control group(P < 0.01).Research conclusions:1.Moderate intensity exercise can reduce blood glucose and insulin levels in db/db mice,control hypertension,improve diabetic symptoms,and reduce aortic injury.2.Moderate intensity exercise inhibited the occurrence of vascular endothelial inflammation and apoptosis by inducing the mir-126-5p/VCAM-1 and mir-126-5p /TRAF7/Caspase3 pathways in the aorta of db/db mice.3.EPC is related to the expression of mir-126-5p in circulation and aorta.Moderate intensity exercise increases the number of circulating endothelial progenitor cells,which is one of the mechanisms for protection of aortic endothelial function. |
PDF Full Text Request