相同摄氧量下向心运动和离心运动对脂代谢肌肉因子激活作用的对比研究

Comparative Study on Concentric and Eccentric Exercise Activating Lipid Metabolism Myokine with Equal Oxygen Uptaking

目的:在相同摄氧量下,对比一次向心和离心运动对骨骼肌分泌脂代谢肌肉因子的激活作用。方法:首先确定SD大鼠在-5°下坡跑离心运动时,摄氧量与相同速度平坡跑无显著差异。然后将66只SD大鼠分为向心运动组(E组)、离心运动组(L组)与对照组(C组)。E组进行一次中等强度0°平坡跑运动,L组进行一次-5°下坡跑运动,并分别在运动后0、6、12、24、48小时处死取材。电镜观察各组肌细胞微结构变化,测试腓肠肌过氧化物酶体增殖物激活受体γ辅激活因子1α(PGC-1α)和纤维连结蛋白Ⅲ型域包含蛋白5(FNDC5)表达以及血清鸢尾素(Irisin)和肌联素(CTRP15)浓度。结果:对PGC-1α和FNDC5蛋白表达进行双因素方差分析显示,时间与运动方案两因素间无显著交互效应(P>0.05),离心与向心训练间存在显著的主效应(P<0.01),且L组PGC-1α、FNDC5蛋白表达量更高;对于血清Irisin和CTRP15浓度,时间和运动方案间存在非常显著交互效应(P<0.01),简单效应分析显示,E组和L组的Irisin和CTRP15在多个时间点相对于C组出现了显著升高(P<0.01),且L组在12、48小时显著高于E组(P<0.01)。结论:相同摄氧量下,离心运动对Irisin上游信号PGC-1α、FNDC5的激活作用比向心运动更显著,且可在训练后更长的时间内促进Irisin与CTRP15高分泌。

Objective To compare the difference in activating skeletal muscles to secrete lipid-metabolismmuscle factor between one set of concentric and eccentric exercise with the same oxygen uptaking.Methods Firstly,it was determined that there was no significant difference in the oxygen uptake between a flat run andrunning on-5°downhill treadmill at the same speed for Sprague-Dawley(SD) rats.Then,66 SD rats were ran-domly divided into a concentric exercise(E) group,an eccentric exercise(L) group and a control(C) group,each of 22.Group E underwent a 0°treadmill exercise of medium-intensity,while Group L did a-5 °down-hill treadmill exercise.The rats were sacrificed 0,6,12,24 and 48 hours after the running,and their tissueswere taken.The electron microscopy was used to observe the changes of myocytes after centrifugation.The pro-tein expression of PPARγ coactivator 1-α(PGC-1α) and Fibronectin type Ⅲ domain-containing protein 5(FNDC5) were detected using the Western blotting,while the serum concentrations of Irsin and C1 q Tumornecrosis factor-related rotein 15(CTRP15) were measured using the enzyme-linked immunosorbent assay(ELISA).Results The two-way ANOVA analysis of PGC-1α and FNDC5 protein expression showed no interaction effectbetween time and exercise type(P>0.05).There was a significant main effect between concentric and eccentrictraining(P<0.01) and the expression of two proteins of group L was higher.For serum irisin and CTRP15 con-centrations,there was a significant interaction between time and exercise type(P<0.01).The simple effect analy-sis found that the Irisin and CTRP15 of group E and L were significantly higher than group C at several timepoints(P<0.01),and those of group L was significantly higher than the E group 12 and 48 hours after the run-ning(P<0.01).Conclusion With the same oxygen uptaking,the eccentric exercise activates Irisin's upstream sig-nal PGC-1α-FNDC5 more significantly than the concentric exercise,and can promote the high secretion levelof Irisin and CTRP15 for a longer time period after exercise.