不同运动强度对急性心肌梗死大鼠心功能的影响及循环miRNAs差异表达

研究不同运动强度对急性心肌梗死大鼠心功能的影响, 分析循环微小RNA(microRNAs, miRNAs)的差异表达与靶基因及基因功能. 制作急性心肌梗死大鼠模型40只,分为4组, 每组10只, 分别为假手术组、单纯心肌梗死组、中等强度持续运动(continuous moderate training, CMT)组和间歇高强度运动(high intensity interval training, HIT)组, CMT组和HIT组大鼠接受运动治疗8周, 用超声心动图评估心功能, 用基因芯片技术测定4组大鼠模型循环miRNAs差异表达, 用生物信息学技术分析不同运动强度下循环miRNAs相关靶基因及基因功能. CMT组和HIT组的治疗显著改善了心肌梗死大鼠心功能和运动耐量, HIT组显著优于CMT组. 单纯心肌梗死组与假手术组相比, 明显上调的循环miRNAs有14个, 明显下调的循环miRNAs有4个. 与单纯心肌梗死组相比, CMT组明显上调的循环miRNAs有11个, 明显下调的循环miRNAs有2个; HIT组明显上调的循环miRNAs有53个, 明显下调的关键miRNAs有41个. 与假手术组相比, 单纯心肌梗死组心肌相关循环miRNAs的差异表达有miR-26a-5p, miR-92a-3p和miR-378a-3p; 与单纯心肌梗死组相比, CMT组有miR-92a-3p, HIT组有miR-34c-3p, miR-23a-3p, miR-98-3p, miR-208a-5p和miR-92-3p. 高强度间歇运动对心肌梗死大鼠心功能和运动耐量的改善作用优于中等强度持续运动, 其循环miRNAs及心肌相关循环miRNAs的差异表达数量明显高于中等强度持续运动, 循环miRNAs差异表达有望作为运动强度和运动效果判断的分子生物学标志物.

Effects of exercise on cardiac function and differential expression of circulating miRNAs in rats with acute myocardial infarction

To study the effects of different exercise intensity on cardiac function and differential expression of circulating microRNAs (miRNAs), target genes and gene function in rats with acute myocardial infarction (AMI). Establish AMI models with 40 rats, divide them into 4 groups, such as Sham operation group, isolated myocardial infarction group, continuous moderately training (CMT) group, and high intensity interval training (HIT) group, with 10 AMI rats in each group. CMT and HIT groups received exercise therapies for 8 weeks. Evaluate cardiac function with echocardiography. Analyze differential expression of circulating microRNAs, related target genes and gene function using miRNAs microarray and bioinformatics technology. CMT and HIT therapies significantly improved cardiac function and exercise tolerance in AMI rats. The effect of HIT group is significantly better than that of CMT group. Compared with Sham operation group, 14 circulating miRNAs were obviously up-regulated, 4 circulating miRNAs were obviously down-regulated in isolated myocardial infarction group. Compared with isolated myocardial infarction group, 11 circulating miRNAs were obviously up-regulated, 2 circulating miRNAs were obviously down-regulated in CMT group, and 53 circulating miRNAs were obviously up-regulated, 41 key miRNAs were obviously down-regulated in HIT group. Compared with Sham operation group, differential expression of myocardium related circulating miRNAs in isolated myocardial infarction group are miR-26a-5p, miR-92a-3p and miR-378a-3p. Compared with isolated myocardial infarction group, there is miR-92a-3p in CMT group, and there are miR-34c-3p, miR-23a-3p, miR-98-3p, miR-208a-5p and miR-92-3p in HIT group. HIT improving cardiac function and exercise tolerance in AMI rats are better than those of CMT. Numbers of differential expression of circulating miRNAs and myocardium related circulating miRNAs with HIT are higher than those of CMT, indicating that circulating miRNAs are expected to be biomarkers for determining exercise intensity and exercise effect.