The Effect Of Aerobic Endurance Exercise And Diet Adjustment On The Expression Of Myocardial LKB1、AMPKa₂in Obese Rats

ObjectiveThrough the establishment of obese rats model, to investigate the effect of aerobicendurance exercise, diet adjustment, aerobic exercise combined with diet adjustmentthree intervention means on myocardial LKB1, AMPKa2expression of obese rats, theeffects of the exercise, dietary interventions can through the LKB1-AMPK a2pathway improve cardiac remodeling provides theory basis for obese individuals.Methods72male SD rat (8weeks of age) randomly divided into control group(C, n=10)and obese model group(M, n=62).Group C fed with normal diet and group M fed withhigh-fat diet(add10%lard,15%sucrose,0.2%cholesterol and0.2%egg yolk powderon the basis of normal feed) for12weeks, with the mean value of body weight ofgroup M more1.96standard deviation increased than group C was regarded the obesemodel is successfully. Then obesity rats were randomly divided into fourgroups:1)Quiet with high-fat fed(HS, n=10),2)Exercise with high-fat fed(HE,n=10),3)Quiet with normal diet fed(NS, n=10) and4)Exercise with normal dietfed(NE, n=10).The group C、HS、NS remained sedentary while the group HE、NEunderwent aerobic endurance exercise for8weeks(20m/min,60min,6d/weeks). Afterintervention, we direct determinate the venous blood glucose level of rat’s tail withglucose test paper. ELISA detection of rats’ serum insulin, enzymatic determination ofserum triglyceride (TG), total cholesterol (TC), and selective precipitation measuredserum low-density lipoprotein cholesterol (LDL-C), high-density lipoproteincholesterol (HDL-C). Oil red staining to observe lipid accumulation in myocardialtissue, Western blotting detect the expression of LKB1and AMPKa2.Result(1)After12weeks of high-fat fed, the body weight of the group M was significantlyhigher than the group C(553.73±31.46vs471.7±28.8, P<0.01). After8weeks of theintervention, the weight of the group NS increased and has no significant comparewith the group HS(P>0.05), but the group HE and group NE has significant decreasedcompare with the group HS(P<0.01), the group NE has decreased most.(2)Compare to group C,8weeks intervention has not significantly change theabsolute weight of heart of other groups. The percentage of the heart mass/body massof the group HS has significantly decreased (P<0.05) but group NE significantlyincreased (P<0.05) own to the body mass changed. The fat mass of the group HS andthe percentage of fat mass/body mass were significantly increased compare with the group C (P<0.01), but both of the group HE and NE were significantly decreasedcompare with the group HS (P<0.01).(3)After8weeks intervention, the fasting blood glucose (FBG)、fasting seruminsulin (FIN)、TC and LDL-C level have no statistical significance (P>0.05). The TGof the group HE was significantly increased than the group C (P<0.01) but group HEand group NE were significantly decreased than the group HS.(4)After the intervention, the oil red O staining results of myocardial in microscopeshowed that the populations of lipid droplets and fatty acid storage increased in thegroup HS、HE、NS and group NE have improved significantly compare with the groupHS.(5)Western blotting results showed that the expression of LKB1、AMPK a2inmyocardial of each group have no significantly difference(P>0.05).Conclusion(1)In present study, we found that three intervention means can’t change theexpression of LKB1、AMPKa2in myocardial indicated that exercise and dietsadjustment through activated the LKB1-AMPK a2pathway to improve energymetabolism of obese individuals remain to be further research.(2) Aerobic endurance exercise and diet adjustment can effectively control the bodyweight, reduce the body fat ratio, improve the relevant indicators in the blood, and hasa good promoting effect for people’s health, and the exercise with the diet interventioneffect is better;(3) Lipid accumulation emerged in the obese rats’ myocardial, exercise and diet candecrease the myocardial lipid accumulation, the effect of exercise with dietintervention is much better.