Effects Of Resistance And Endurance Exercise On The Expression Of Liver Autophagy Associated Protein In Obese Mice

At present,with the increase of the number of overweight and obese people growing,the number of patients suffering from obesity-related diseases,such as diabetes and fatty liver,is increasing day by day,which has caused widespread concern.Since the current obese population is too large,it is particularly important to find effective methods that can prevent obesity.Among them,autophagy mechanism is considered to be a new direction and a new hotspot in the study of obesity-related metabolic diseases in recent years,and the Japanese Professor Daisuke Shinichi won the 2016 Nobel Prize in Physiology and Medicine for the study of autophagy mechanisms.Later,there are studies on autophagy to emerge and they are emerging in an endless stream.Autophagy is a relatively conservative mechanism in the body that can participate in the breakdown of lipids and increase the body’s energy expenditure,thus preventing the occurrence and development of obesity.In this experiment,by observing the intervention of exercise and high-fat diet,the contents of TC and TG in serum and liver of mice,and the expression of autophagy-related proteins(Beclin1,Lc3,p62)in the liver,it explores the effect of hepatic autophagy between resistance and endurance exercise to mice,provide potential autophagy pathway targets for drug intervention in obesity,At the same time,it provides new theoretical support and practical strategies for further understanding of the metabolic diseases such as exercise resistance to obesity and exercise prevention and treatment of hepatic lipid abnormalities.Methods: A total of 100 4-week-old C57BL/6 male mice were used,of which 8(NNC)were in the normal feed group.The remaining 92 mice were fed with high-fat diet and the obese model was replicated.Obesity was increased by 20% compared to the normal diet.Thirty-two mice were selected as obese mouse models.According to the purpose of the experiment,obese mice were randomly divided into: high-fat control group(HHC),after high-fat diet,normal diet control group(HNC),high-fat and aerobic exercise(HNE),High fat and resistance exercise(HNR),8 in each group.The HNE group and the HNR group performed eight weeks of treadmill and ladder training,respectively.Treadmill Training Program: The initial speed is set to 15m/min for a total of 20 min,after which the speed andtime are adjusted according to the mouse’s adaptation status,starting at 15m/min for 10 min,then increasing the speed to 25m/min for 40 min,and then reducing to 15m/min for 10 min,5weeks/day,8 weeks.Ladder training: 10% of the mouse body weight on the first day,increasing by 10% daily.After 150% of body weight was stopped,6 times per day,5 times per week for 8 weeks,HHC mice were fed with high-fat diet,and other groups of mice were fed with common feed.Before the animals were sacrificed,they were allowed to drink and not allowed to eat for 24 hours and the blood was collected from the eyeballs.The levels of TC and TG in blood glucose and liver were measured by ELISA,and the expression of Beclin1,Lc3,and p62 proteins in liver of mice was determined by Western blot.The resulting data was analyzed for variance using SPSS20.0 software.Result:(1)After 8 weeks of high-fat diet,TC content was significantly increase in the serum and liver of mice(P<0.05),TG content was also significantly increase in the serum(P<0.05),But TC content in the liver was not significantly increased and it has no statistical significance(P>0.05).The weight and lee’s of HHC group was significantily higher than the HNC group(P<0.05),with significant differences.At the same time,after 8 weeks high-fat diet intervention,it was also found that the expression of autophagy-related protein Beclin-1(P<0.05)and Lc3Ⅱ/Ⅰ(P<0.05)were significantly reduced in the liver,and the expression of p62 was significantly increased(P<0.05).It shows that high-fat diet can reduce activity of autophagy in obese mice.(2)After 8 weeks of resistance and endurance exercise,content of TG(P<0.05)and TC(P<0.05)were significantly reduced in the serum and liver of obese mice.Comparison before and after exercise intervention,there was not significant difference in weight(P>0.05).At the same time,after 8 weeks of resistance and endurance exercise,it was also found that expression of autophagy-related protein Beclin-1(P<0.05)and Lc3Ⅱ/Ⅰ(P<0.05)were significantly increased in the liver,and the expression of p62 was significantly reduced(P<0.05).It shows that resistance and endurance exercise can increase activity of autophagy in obese mice.Conclusion: High-fat diets can increase body weight and blood lipids in mice,reduce activity of autophagy,increase lipid accumulation in the body,and increase the incidence ofobesity and related diseases.Both resistance and endurance exercise can promote the increase activity of liver autophagy in obese mice,increase the metabolism of lipids in the liver,and reduce the production and accumulation of lipids.Therefore,both resistance and endurance exercise can be used as One of the means to prevent and treat obesity and related liver diseases.