Effects Of Aerobic Exercise On LKB1-AMPK-ACC In The Adipose Of Obese Rats

Objective:1. By means of observing the impact of the high-fat diet on LKB1-AMPK signaling pathway ofSD rats’ fat tissue, this paper provides experimental evidence for revealing the mechanism ofobesity;2. Through exploring the impact of exercise intervention on LKB1-AMPK signalingpathway of obese rats’ fat tissue, this paper provides experimental basis for body fat reductionmechanism by means of exercise.Methods：1.4815-month-old male SD rats are randomly divided into2groups,10rats as the normalcontrol group (CON) fed on normal diet, and38rats as the obesity model group fed on high-fatdiet for8weeks for the purpose of establishing obesity models.2. After8-week high-fat diet forobesity model group, obesity modeling could be taken as successful if rats in obesity modelgroup weigh20%more than the body weight of the normal control group. Top30heaviestobese rats are selected from the obese rats which are consistent with successful obesitymodeling and randomly divided into three groups: obesity control group （OB） for10rats,obesity-exercise group1（OB+EX1） for10rats and obesity-exercise group2（OB+EX2）for10rats, Eight-week swimming training is planned for OB+EX1and OB+EX2.3. Rats ineach group are taken for sampling at the end of the16th week and all groups of rats are fastedfor12hours before sampling. The rats in OB+EX1are taken for sampling24hours after thelast exercise, and the rats in OB+EX2are taken for sampling48hours after the last exercise. Itis body weight and the content of fat, blood glucose, serum triglycerides, total cholesterol, highdensity lipoprotein, low density lipoprotein, and protein expression and phosphorylation levelsof related indicators in the LKB1-AMPK-ACC signal pathway of fat tissue for rats in eachgroup that is to be determined.Results：1. Compared with CON, the body weight, abdominal fat weight of OB significantlyincrease(P<0.05，P<0.05); serum triglycerides, total cholesterol and low density lipoproteinsignificantly increase (P<0.05, P<0.05, P<0.05) while high density lipoprotein significantlydecreases (P<0.05); LKB1protein expression and phosphorylation level in fat tissuesignificantly decrease (P<0.05); AMPKα1protein expression and phosphorylation level significantly decrease (P<0.05, P<0.05); AMPKα2protein expression and phosphorylationlevel significantly decrease (P<0.05, P<0.05); AMPKα1/2protein expression tends to decrease(P>0.05) while its phosphorylation level significantly decreases (P<0.05); ACC proteinexpression significantly increases (P<0.05) while its phosphorylation level significantlydecreases (P<0.05).2. Compared with OB, the body weight, abdominal fat weight of OB+EX1and OB+EX2significantly decrease（P<0.05，P<0.05）；serum triglycerides and low densitylipoprotein significantly decrease(P<0.05，P<0.05) while high density lipoprotein significantlyincreases （P<0.05）； LKB1protein expression and phosphorylation level in fat tissuesignificantly increase（P<0.05）；AMPKα1protein expression and phosphorylation levelsignificantly increase (P<0.05, P <0.05); AMPKα2protein expression significantly increases(P<0.05, P<0.05); AMPKα2phosphorylation level of OB+EX1significantly increase（sP<0.05）;AMPKα1/2protein expression and phosphorylation level significantly increases（P<0.05，P<0.05; ACC phosphorylation level significantly increases (P <0.05).3. Compared withOB+EX1, only AMPKα1phosphorylation level in all test indicators of OB+EX2significantlydecreases (P <0.05) while there is no difference for other test indicators.Conclusion：1. The damage to LKB1-AMPK-ACC signal transduction pathway of the obese rats’ fat tissuemay be one of the mechanisms that cause the body’s fat metabolism disorders.2. Long-termaerobic exercise can alleviate fat metabolism disorders through improving LKB1-AMPK-ACCsignal transduction pathways of fat tissue. LKB1plays an important role in activatingAMPK-ACC signaling pathway of fat tissue by exercise.Suggestion：If the experimental conditions permit, further attention should be paid to determining theactivity of ACC downstream protein malonyl coenzyme A decarboxylase (MCD) and malonylcoenzyme A (MA) concentration, and exploring the consistency of protein expression andactivity changes in the entire signaling pathway combined with the results of biochemicalindicators test. A study on LKB1upstream cascade protein or other biologically activesubstances can be made to explore if LKB1is active protein that feels energy changes in cells atexercise time.