低氧调控大鼠运动性肌损伤的特征MicroRNA表达

The Specific MicroRNA Expression Influenced by Hypoxia of Exercises-induced Muscle Damage Rats

目的:筛选低氧调控大鼠运动性肌损伤(EIMD)的特征MicroRNA(miRNA),预测分析特征miRNA调控膜损伤的靶点。方法:56只健康雄性SD大鼠平均分为安静对照组(C),运动后常氧休息24小时组(N24)、48小时组(N48)、72小时组(N72)以及运动后低氧暴露24小时组(H24)、48小时组(H48)、72小时组(H72),采取一次间歇性离心运动复制EIMD模型。采用伊文氏蓝(EBD)染色法鉴定EIMD膜损伤特征,基因芯片进行低氧和常氧之间差异性miRNA筛选,RT-q PCR验证芯片结果后获得特征miRNA表达谱,比对各组的特征miRNA和膜损伤相关特征蛋白以及信号通路核心分子的m RNA表达,预测和分析特征miRNA的可能靶基因及调控途径。结果:筛选并验证得出5条低氧调控大鼠EIMD的特征miRNA:miR-694、miR-1904、miR-881*、miR-211-5p、miR-465-5p。通过特征miRNA、膜损伤相关蛋白和相关通路核心分子进行综合对比以及生物信息学分析得出,miR-694的靶标可能性较大的是dystrophin、JNK和AKT以及mTOR;miR-211-5p的靶标可能性较大的是mTOR。结论:低氧可以影响EIMD大鼠腓肠肌miRNA表达谱发生明显改变。miR-694和miR-211-5p有可能与低氧调控EIMD膜损伤的miRNA调控机制密切相关。

Objective To screen the specific MicroRNAs（miRNAs）expressions influenced by hypoxia,and predict the specific miRNAs regulated target of sarcolemmal damage of exercise-induced muscle damage（EIMD）rats. Methods Fifty-six male Sprague-Dawley rats were randomly divided into a normoxic control group（C）,a post-exercise 24-hour normoxic recovery group（N24）,a post-exercise 48-hour normoxic recovery group（N48）,a post-exercise 72-hour normoxic recovery group（N72）,and post-exercise 24/48/72-hour hypoxic recovery groups（H24/H48/H72）. The EIMD model was introduced to all rats through an acute eccentric exercise and the EIMD characteristics were verified using Evan＇s blue dye（EBD）staining.Differentially expressed miRNAs between hypoxia and normoxia were detected using the microarray assay. The specific miRNAs expressions were further validated using the real-time quantitative PCR（RT-q PCR）. The specific miRNAs and m RNA expressions of associated proteins and core molecules in related pathway of the sarcolemmal damage were compared among the different groups to analyze and predictargets of specific miRNAs and its regulation approach. Results Five specific expressed miRNAs were found,including miR-694,miR-1904,miR-881＊,miR-211-5p and miR-465-5p. The result of comparative analysis and bioinformatics indicated that predicted targets of miR-694 were more likely to include dystrophin,JNK,AKT and mTOR,and that of miR-211-5p was mTOR. Conclusion The expression profile of miRNAs in EIMD rat is significantly affected by hypoxia.MiR-694 and miR-211-5p may be closely related to the mechanism in specific miRNA expression,which is influenced by hypoxia in the sarcolemmal damage of EIMD rats.