摘要
背景:目前,关于运动预适应的心肌保护机制尚未完全阐明,据报道Rho/ROCK信号通路在心血管疾病中起到关键作用,运动预适应是否通过Rho/ROCK信号通路对心肌起到保护作用有待研究。目的:基于Rho/ROCK信号通路探讨运动预适应在力竭运动大鼠心肌损伤中的作用。方法:将60只5周龄的SPF级SD雄性大鼠随机分为3组:安静对照组、单纯力竭运动组、运动预适应+力竭运动组,各组建模结束后1 h,取血清进行全生化分析检测心肌酶谷草转氨酶、磷酸肌酸激酶、乳酸脱氢酶水平,取心肌组织标本进行苏木精-碱性复红-苦味酸染色观察心肌组织病理变化,分析缺血缺氧程度,TUNEL法观察心肌细胞凋亡情况,ELISA法检测心肌组织肿瘤坏死因子α和白细胞介素10水平,Western blot检测心肌组织RhoA、ROCK1、ROCK2、Bax和Bcl-2蛋白的表达。结果与结论:①单纯力竭运动组谷草转氨酶、磷酸肌酸激酶、乳酸脱氢酶水平显著高于安静对照组(P<0.05);而运动预适应+力竭运动组谷草转氨酶、磷酸肌酸激酶、乳酸脱氢酶水平显著低于单纯力竭运动组(P<0.05);②单纯力竭运动组心肌细胞界限不清楚,呈现出较多斑块状或片状艳红色样区域,与安静对照组相比,有明显的缺血缺氧改变;运动预适应+力竭运动组部分心肌细胞界限不清楚,出现部分斑块状艳红色染色,较单纯力竭运动组缺血缺氧程度明显减轻;③单纯力竭运动组较安静对照组凋亡指数值明显升高,运动预适应+力竭运动组与单纯力竭运动组相比凋亡指数值明显下降(P<0.05);④单纯力竭运动组的肿瘤坏死因子α和白细胞介素10水平显著高于安静对照组(P<0.05),运动预适应+力竭运动组肿瘤坏死因子α和白细胞介素10水平显著低于单纯力竭运动组(P<0.05);⑤单纯力竭运动组的Bcl-2/Bax显著低于安静对照组(P<0.05),运动预适应+力竭运动组Bcl-2/Bax显著高于单纯力竭运动组(P<0.05);⑥与安静对照组相比,单纯力竭运动组RhoA、ROCK1、ROCK2蛋白水平明显升高,而运动预适应+力竭运动组RhoA、ROCK1、ROCK2蛋白水平显著低于单纯力竭运动组(P<0.05);⑦结果表明,运动预适应对心肌损伤具有保护作用,可改善大鼠的心脏功能,其作用机制可能与Rho/ROCK通路有关。
BACKGROUND:At present,the mechanism of exercise preconditioning for myocardial protection has not been fully elucidated.It is reported that Rho/ROCK pathway plays a key role in cardiovascular disease.Whether exercise preconditioning adapts to the myocardium through the Rho/ROCK signaling pathway remains to be studied.OBJECTIVE:To investigate the role of exercise preconditioning in rats with myocardial injury after exhaustive exercise.METHODS:Sixty male Sprague-Dawley rats of 5 weeks old were randomly divided into three groups:control group,simple exhaustive exercise group(EE group),and exercise preconditioning group after exhaustive exercise(EP+EE group).At 1 hour after modeling,a serum sample from each rat was taken for biochemical analysis.The levels of aspartate aminotransferase,phosphocreatine kinase,and lactate dehydrogenase were detected.Myocardial tissue samples from each rat were taken for pathological observation using hematoxylin-alkaline reddish-picric acid staining.TUNEL method was used to observe apoptosis in the myocardial tissue.The levels of tumor necrosis factor-αand interleukin-10 in the myocardial tissue were detected by ELISA.The expression of RhoA,ROCK1,ROCK2,Bax,and Bcl-2 protein was analyzed by western blot.RESULTS AND CONCLUSION:The levels of aspartate aminotransferase,phosphocreatine kinase,and lactate dehydrogenase of the EE group were significantly higher than those of the control group(P<0.05).The levels of aspartate aminotransferase,phosphocreatine kinase,and lactate dehydrogenase of the EP+EE group were significantly lower than those of the EE group(P<0.05).The boundary of cardiomyocytes was unclear in the EE group,in which there were more plaque-like or flaky red-like areas as well as more obvious ischemia-anoxia changes as compared with the control group.Some cardiomyocytes presented with unclear boundary in the EP+EE group with some plaque-like brilliant red-like areas,and the degree of ischemia and anoxemia was significantly lower in the EP+EE group than the EE group.The apoptotic index value of the EE group was significantly higher than that of the control group,and the apoptotic index value of the EP+EE group was significantly lower than that of the EE group(P<0.05).The tumor necrosis factor-αand interleukin-10 levels in the EE group were significantly higher than those in the control group(P<0.05).The tumor necrosis factor-αand interleukin-10 levels in the EP+EE group were significantly lower than those in the EE group(P<0.05).The Bcl-2/Bax of the EE group was significantly lower than that of the control group(P<0.05).The Bcl-2/Bax of the EP+EE group was significantly higher than that of the EE group(P<0.05).The levels of RhoA,ROCK1 and ROCK2 in the EE group were significantly higher than those in the control group.The levels of RhoA,ROCK1 and ROCK2 in the EP+EE group were significantly lower than those in the EE group(P<0.05).These findings indicate that exercise preconditioning has a protective effect against myocardial injury and improves cardiac function in rats.The mechanism may be related to the Rho/ROCK pathway.
作者
刘晓晨
王改凤
Liu Xiaochen;Wang Gaifeng(Department of Physical Education,Henan University of Finance and Economics,Zhengzhou 450046,Henan Province,China;First Ward of Encephalopathy,Henan Hospital of Traditional Chinese Medicine,Zhengzhou 450002,Henan Province,China)
出处
《中国组织工程研究》
CAS
北大核心
2020年第11期1714-1719,共6页
Chinese Journal of Tissue Engineering Research
基金
河南省体育局课题研究项目(2018026)，项目负责人：王改凤~~
关键词
运动预适应
力竭运动
Rho/ROCK
心肌损伤
心功能
细胞凋亡
蛋白表达
exercise preconditioning
exhaustive exercise
Rho/ROCK
myocardial injury
cardiac function
apoptosis
protein expression
