The Changes Of Lipohydrolase Activity In Obese Mice After Acute High-Intensity Intermittent Exercise

Objective:Obesity is Seriously harmful to human health,and exercise is accepted by the public as a safe and reliable way to lose weight.At present,a large number of studies have confirmed that the weight loss effect of long-term high-intensity intermittent exercise(HIIT)is similar to that of long-term medium-intensity continuous exercise(MICT),and even HIIT weight loss effect is better.There is evidence that the possible mechanism of the better weight loss effect of HIIT occurs after exercise.Therefore,this study obServed the changes of lipohydrolase expression and phosphorylation regulation in different parts of adipose tissue of mice after HIIT and MICT exercise with the same amount of exercise,in order to explore the possible mechanism of better weight loss effect of HIIT.Method:4-week-old C57BL/6 female mice(weight 14.4±0.97g)were fed adaptively for one week and randomly divided into two groups:normal diet group(C,n=10)and high fat diet intervention group(H,n=60).The H group received 15-week high-fat diet intervention to induce obesity(feed:60% standard diet,16% granulated sugar,5% lard,18% egg yolk powder and 1% sodium cholate).Obesity criteria:The body weight of mice in H group was more than 10% of the average body weight of mice in group C.Then 42 obese mice were randomly divided into HFD group,MICT group and HIIT group.The exercise plan is as follows:The MICT group exercises for 45 minutes with 50%-70% maximum oxygen uptake peak intensity,and the HIIT group exercises with 90%-110% maximum oxygen uptake peak intensity for 1 minute,50%-70% maximum oxygen uptake peak intensity for 2 minutes,cycle for 12 times of High-Intensity Intermittent Training,and ensure that the two run the same distance.There was no exercise intervention in the HFD group,and the samples were taken at the same time as the MICT and HIIT groups.After training,MICT and HIIT were divided into immediately,1 hour and 12 hours after exercise to collect adipose tissue from groin(Subcutaneous)and periuterine(Visceral)adipose tissue of mice.Western Blot was used to detect the expression of ATGL,HSL and their phosphorylation sites Ser563 and Ser660,AMPK and the phosphorylation sites Thr172.The data were analyzed by two-way ANOVA,P<0.05 was considered to be significant difference,P<0.01 was considered to be very significant difference.Result:(1)Compared with HFD group,the ATGL of subcutaneous fat in MICT group increased significantly immediately and 1 hour after exercise(P<0.05).(2)Compared with HFD group,HSL of visceral fat in MICT group increased immediately after exercise(P<0.05).In HIIT group,the HSL-Ser563 of subcutaneous fat increased immediately and 1 hour after exercise(P < 0.01).HSL-Ser563 of visceral fat increased immediately and 1 hour after exercise in MICT group and immediately after exercise in HIIT group(P<0.01,P<0.05),and the main effect of HIIT was higher than that of MICT(P<0.05).In HIIT group,the HSL-Ser660 of subcutaneous fat increased 12 hours after exercise(P<0.01),and the main effect of HIIT was higher than that of MICT(P<0.05).In MICT group,visceral fat HSL-Ser660 increased at 1 hour after exercise(P<0.05),and the main effect of MICT was higher than that of HIIT(P<0.05).(3)Compared with HFD group,AMPK-Thr172 of subcutaneous fat in HIIT group increased after 12 hours of exercise(P<0.05).In HIIT group,visceral fat AMPK-Thr172 increased after 1 hour of exercise(P<0.01).Conclusion:Compared with MICT,acute HIIT could significantly activate the lipolysis activity of HSL in subcutaneous adipose tissue of obese mice and promote fat mobilization,and the effect lasted until 12 hours after exercise.