持续运动和间歇运动对高脂喂养大鼠肝脏Rev-erbα和SCD1表达的影响

Effects of Mild- intensity Endurance and Heavy- intensity Interval Exercise on Hepatic Rev- erbα and SCD1 in Rats Fed with High- fat Diet

目的探讨低强度持续运动和大强度间歇运动对高脂喂养大鼠肝脏Rev-erbα和SCD1表达的影响及其肝脏脂质代谢调节的分子生物学机制。方法 37只雄性Sprague-Dawley大鼠分为对照饮食安静组(CS组)、高脂饮食安静组(HS组)、高脂饮食持续运动组(HE组)和高脂饮食间歇运动组(HI组)。HE组和HI组分别采用低强度持续运动和大强度间歇运动方式训练,每周5 d,周期为10周。检测体质量、血清学指标、肝脏中性脂质含量以及靶分子Rev-erbα、SCD1基因和蛋白表达量。结果 HE组和HI组体质量、血脂和血糖含量较HS组降低,QUICKI指数显著增加;HI组中性脂质含量较其它高脂组显著降低。HS组SCD1 mRNA表达量较CS组明显增加;Rev-erbαmRNA表达量显著下降。HI组SCD1 mRNA表达量明显降低,Rev-erbαmRNA表达量升高;且HI组与其它高脂组均存在显著差异。靶分子蛋白表达量与转录水平基本一致。结论大强度间歇运动预防高脂饮食喂养大鼠机体代谢异常和肝脏脂质沉积,其效果明显优于低强度持续运动方式,Rev-erbα对SCD1的代谢调控可能是影响高脂喂养大鼠肝细胞脂质代谢调节的重要分子机制。

Objectives To discuss the effects of mild - intensity endurance exercise and heavy - intensity interval exercise on expressions of Rev - erbα and SCDI in livers of high - fat diet rats, and to explore the molecular mechanism of hepatic lipid metabolism. Methods Thirty -seven Sprague - Dawley rats were divided into five groups with stratified random sampling： control diet/sedentary group （CS）, high -fat diet/sedentary group （HS）, high -fat diet/endurance exercise （HE）, high - fat diet/interval exercise （HI）. After acclimation, exercise was performed on a motor - driven rodent treadmill according to exercise protocols, respectively. Blood samples and lipid content in hepatocyte were collected and evaluated. Relative ex- pression of Rev - erbα and SCD1 in liver was determined by real - time PCR and western blotting. Results Body weight, serum lipid and GLU in HE and HI were lower than those in HS, while insulin sensitivity was significantly improved in HE and HI. Lipid accumulation in HI was lower than those in HS and HE. HS induced down regulation of Rev - erbα mRNA and up -regulation of SCD1. HI elevated Rev- erbα sharply, which was higher significantly than those in HE. SCDlmRNA was decreased in all exercised rats, and HI amplified the change. Conclusions Heavy - intensity interval exercise sought to re- verse the adverse effects of high - fat diet, which is more timely and effective than mild - intensity endurance exercise. Rev - erbα may play an important regulating role in the expression of SCD1, which is important molecular mechanism of lipid metabolic regulation in hepatic cells of high - fat diet rats.