负载PGC-1α的sEV^(P)改善小鼠心肌梗死后心功能  

PGC-1α-loading sEV~P improves cardiac function after myocardial infarction in mice

作　　者：雒海霞 王珂鑫 贾晓杰 亓秉超 李妍 LUO Haixia;WANG Kexin;JIA Xiaojie;QI Bingchao;LI Yan(Department of Cardiology,Tangdu Hospital,Air Fore Medical University,Xi'an 710000,China)

机构地区：[1]空军军医大学唐都医院心血管内科,西安710000

出　　处：《山西医科大学学报》2025年第3期240-251,共12页Journal of Shanxi Medical University

基　　金：国家自然科学基金资助项目(82070385)。

摘　　要：目的探究负载过氧化物酶体增殖体激活受体γ共激活因子-1α(peroxisome proliferator-activated receptor gamma coactivator-1α,PGC-1α)的小细胞外囊泡(small extracellular vesicle,sEV)对缺氧心肌细胞及小鼠心肌梗死后心功能的影响。方法对小鼠心肌梗死数据集(GSE775和(GSE6580中线粒体复合体相关基因和PGC-1α的表达进行差异分析。采用差速离心法提取小鼠骨髓间充质干细胞(bone marrow mesenchymal stem cell,BMSC)来源的sEV和PGC-1α过表达BMSC来源的sEV(sEV^(P))。qRT-PCR检测sEV和sEV^(P)中PGC-1αmRNA含量。原代心肌细胞分为对照(control,Con)组、sEV组和3sEV^(P)组,并进行缺氧处理,利用Seahorse测定线粒体代谢水平,DHE染色测定活性氧含量。小鼠随机分为4组:假手术(sham)组、心肌梗死(myocardial infarction,MI)组、MI+sEV组和MI+sEV^(P)组。通过左前降支动脉结扎术构建小鼠心肌梗死模型。术后1 d,通过TTC染色评估心肌梗死面积,透射电镜观察线粒体形态,TUNEL染色检测细胞凋亡情况。术后28 d,通过超声心动图评估心功能。结果差异基因分析显示,心肌梗死小鼠心肌组织中线粒体复合体相关基因和PGC-1α的表达显著下调(P<0.05)。qRT-PCR检测表明,sEV^(P)中PGC-1αmRNA的含量显著高于sEV(P<0.05)。在缺氧条件下,与Con组相比,sEV^(P)组心肌细胞的线粒体代谢显著改善(P<0.05),胞内活性氧含量降低(P<0.05)。心肌梗死术后1 d,与MI组相比,MI+sEV^(P)组小鼠的心肌梗死面积减少(P<0.05),线粒体嵴结构损伤减轻(P<0.05),活性氧水平降低(P<0.05),细胞凋亡减少(P<0.05)。心肌梗死术后28 d,MI+sEV^(P)组小鼠的左心室收缩功能较MI组显著改善(P<0.05)。结论sEV^(P)通过提高缺氧心肌细胞中PGC-1α的表达,改善线粒体嵴结构和代谢水平,降低胞内活性氧含量和细胞凋亡,最终减少心肌梗死面积并改善心肌梗死后心功能,表现出良好的心肌保护作用。Objective To investigate the effect of small extracellular vesicle(sEV)loaded with peroxisomeγproliferator-activated receptor gamma coactivator-1α(PGC-1α)on hypoxic cardiomyocytes and cardiac function after myocardial infarction in mice.Methods Differential expression analysis of mitochondrial respiratory chain genes and PGC-1αwas performed using the mouse myocardial infarction datasets GSE775 and GSE6580.Mouse bone marrow mesenchymal stem cell(BMSC)-derived sEV and BMSC-derived sEV overexpressing PGC-1α(sEV^(P))were isolated by differential centrifugation,and qRT-PCR was used to measure PGC-1αmRNA level in sEV and sEV^(P).The primary cardiomyocytes were divided into control(Con)group,sEV group and sEV^(P) group,and the cells were then cultured under hypoxic condition after corresponding treatment.Seahorse was used to assess mitochondrial metabolic activity,and DHE staining was used to measure intracellular reactive oxygen species(ROS)level.The mice were randomly divided into four groups:sham group,myocardial infarction(MI)group,MI+sEV group,and MI+sEV^(P) group.The MI model was constructed by left anterior descending artery ligation.At day 1 after MI,TTC staining was used to evaluate the myocardial infarction area,transmission electron microscopy(TEM)was used to observe mitochondrial morphology,and TUNEL staining was performed to detect cell apoptosis.Echocardiography was conducted to assess cardiac function at day 28 after MI.Results Differential analysis revealed that the expressions of mitochondrial respiratory chain genes and PGC-1αin myocardial tissue from MI mice were significantly downregulated(P<0.05).qRTPCR result showed that PGC-1αmRNA level in sEV^(P) was significantly higher than that in sEV(P<0.05).Compared with Con group,the mitochondrial metabolism of cardiomyocytes was significantly improved while the intracellular ROS level was reduced in sEVP group under hypoxic condition(P<0.05).At day 1 after MI,compared with MI group,the myocardial infarction area was significantly reduced in MI+sEV^

关 键 词：心肌梗死 骨髓间充质干细胞 小细胞外囊泡 PGC-1Α 线粒体 活性氧 细胞凋亡 

分 类 号：R542.22[医药卫生—心血管疾病]