不同运动方式诱导肥胖大鼠肝脏脂联素信号通路调控脂代谢的研究

Effects of Different Exercise Training on Lipid Metabolism by Activating Hepatic Adiponectin Signaling Pathway in Obese Rats

目的:观察和研究8周有氧运动及抗阻运动干预对肥胖大鼠肝脏"APN-PPARα-CPT1"信号通路的影响,并探讨两种运动方式通过APN信号通路对机体脂代谢的调控作用。方法:高脂饮食诱导的肥胖雄性SD大鼠随机分为安静对照组(CON组)、有氧运动组(AE组)和抗阻运动组(RE组),每组各10只。AE组大鼠进行8周的跑台训练,每周训练5天,每次60 min,运动强度为65%VO_2max,通过测定VO_2max设定跑速。RE组大鼠利用"负重爬梯法"进行8周的抗阻训练,每2天训练1轮,负荷逐级递增。完成最后一次训练24 h后,大鼠禁食过夜进行取材。血液样本用来测试血脂、脂联素水平;肝脏组织样本用来测试APN、PPARα、CPT1的基因及蛋白表达;剥离肾周脂肪和附睾脂肪,用吸水纸吸干表面水分后称重。结果:8周运动干预后,AE组和RE组大鼠的体重、脂肪重量、总胆固醇水平显著低于CON组(P<0.05),AE组大鼠脂体比也显著低于CON组(P<0.05)。AE组和RE组APN、PPARα、CPT1基因表达水平均显著高于CON组(P<0.01),且AE组也显著高于RE组(P<0.01)。在蛋白表达水平上,RE组APN和PPARα蛋白表达水平显著高于AE组(P<0.05),但AE组CPT1蛋白表达水平显著低于CON组(P<0.05)。结论:经过8周的有氧运动或抗阻运动干预,肥胖大鼠肝脏"APN-PPARα-CPT1"信号通路中各因子的基因表达水平都有了显著提高,在一定程度上减轻了肥胖大鼠的体重,减少了体脂堆积并改善了血脂水平。相对于抗阻运动,有氧运动对肥胖大鼠肝脏"APN-PPARα-CPT1"信号通路及脂代谢的影响更加显著。

Objective:To investigate the effects of aerobic and resistance exercise training on lipid metabolism by activating the hepatic“APN-PPARα-CPT1”signaling pathway in obese rats.Methods:The high fat diet-induced obese male SD rats were randomly assigned into control group(CON,n=10),aerobic exercise group(AE,n=10),and resistance exercise group(RE,n=10).The rats in AE group were trained by running on a treadmill for 8 weeks,5 days/week,60 min/day,the running speed was set at 65%O2max.The rats in RE group completed an 8-week resistance exercise program by climbing on a ladder.The rats were trained once in every two days,and the load was adjusted according to their exercise capacity in each time.After the last training session for 24 hours,the rats were killed after overnight fasting,the blood samples,liver tissues,perirenal and epididymal fat were collected for further analysis.Results:After the 8-week exercise training,the body weight,serum adiponectin and TC in AE and RE group were lower than CON group(P<0.05),the ratio of fat to weight was also lower in AE than CON group(P<0.05).The gene expression of APN、PPARα、CPT1 in AE and RE group were higher than CON group(P<0.01),and AE group was higher than RE group as well(P<0.01).In addition,the protein expression of APN and PPARαwere higher in RE group than AE group(P<0.05),but the CPT1 protein expression was lower in AE group comparing with CON group(P<0.05).Conclusion:Both the 8-week aerobic and resistance exercise training increased the gene expression of hepatic“APN-PPARα-CPT1”signaling pathway,which resulted in the reduction of body weight,fat weight and improvement of the blood lipid profiles in obese rats.Compared with resistance exercise,aerobic exercise was more effective in activating“APN-PPARα-CPT1”signaling pathway and regulating lipid metabolism.