L-肉碱及运动对超重小鼠心肌H-FABP和PPARα的影响

Effects of L- carnitine and Exercise on Myocardial PPARα and H-FABP in Overweight Mice

目的探讨L-肉碱及运动对超重小鼠心肌脂代谢的影响。方法 C57BL/6小鼠给予3周高脂饮食建立超重模型,造模成功后的小鼠随机分为超重对照组(OC组)、超重肉碱组(OL组)、超重运动组(OE组)和超重运动结合肉碱组(OEL组)。OE和OEL组小鼠进行6周的游泳训练,6次/周;同时OL和OEL组小鼠补充L-肉碱。检测心肌H-FABP、PPARα蛋白表达量及FFA、肉碱含量。结果 OL和OEL组心肌肉碱含量较OC组升高;OE和OEL组心肌FFA含量均低于OC组,且OEL组低于OE组;OE和OEL组心肌H-FABP表达量较OC组升高;干预各组心肌PPARα的表达量均高于OC组,且OEL组高于OE组。结论 (1)有氧运动可上调心肌H-FABP和PPARα蛋白表达水平,促进心肌对FFA的氧化利用。(2)L-肉碱的补充对超重小鼠心肌H-FABP的蛋白表达无明显调控作用。(3)运动结合L-肉碱降低心肌FFA含量的效果优于单纯运动,其机制与上调PPARα蛋白表达有关。

Objective To explore the effects of L- carnitine and aerobic exercise on myocardial fatty acid metabolism in overweight mice. Methods C57 BL /6 mice were given 3 weeks to build a high- fat diet overweight model. They were randomly divided into following groups： overweight control（ OC） group,overweight L- carnitine（ OL） group,overweight exercise（ OE） group and overweight exercise plus L- carnitine（ OEL） group. Mice in groups OE and OEL underwent swimming6 times per week for 6 weeks. L- carnitine was applied to groups OL and OEL at the same time. FFA and carnitine in myocardium were tested. we also observed the protein expressions of Myocardial PPARαand H- FABP. Results Compared with control group,myocardial carnitine was increased in groups OL and OEL. Myocardial FFA concentration in groups OE and OEL was down- regulated. moreover,the group OEL do better than the group OE. The protein expression of myocardial H-FABP was increased in groups OE and OEL. PPARα protein level in each control group was up- regulated,moreover,group OELwere higher than group OE. Conclusion 1） Long- term aerobic exercise could increase the protein expression of myocardial PPARα and H- FABP on athletic mice,and could facilitatefree fatty acid oxidation. 2） L- carnitine had no distinct effect on the protein expression of myocardial H- FABP. 3） Exercise plus L- carnitine was more superior in regulation of FFA than exercise due to increasing the protein expression of PPARα.