脐带MSC来源外体上调Smad7表达修复大鼠急性心肌损伤  

Human umbilical cord mesenchymal stem cell derived exosomes upregulates Smad7 expression for repairing acute myocardial injury in rats

作　　者：曹文明[1] 孙丽[1] 赵媛媛[1] 马洁[1] 孙晓仙 展洁[1] 钱晖[1] 许文荣[1] 朱伟[1] 

机构地区：[1]江苏大学医学院,江苏镇江212013

出　　处：《临床检验杂志》2015年第7期527-531,共5页Chinese Journal of Clinical Laboratory Science

基　　金：国家自然科学基金(81270214)

摘　　要：目的探讨人脐带间充质干细胞来源的外体(huc-exosomes)对SD大鼠急性心肌梗死(AMI)的修复作用及其可能的分子机制。方法体内构建SD大鼠AMI模型,分为假手术组、AMI+PBS组和AMI+exosomes组,小动物高频彩色超声仪检查心功能;72 h后处死取心肌组织,western blot检测组织内Smad7蛋白变化;体外培养心肌细胞系H9C2及原代培养心肌组织细胞,免疫荧光法鉴定原代培养心肌组织细胞,分为正常氧+PBS、正常氧+exosomes、缺氧+PBS、缺氧+exosomes 4组,分别提取各组的蛋白质或RNA,用定量PCR、western blot分别检测Smad7 mRNA和蛋白质变化。结果成功构建了SD大鼠AMI模型,超声心动图结果显示,尾静脉注射huc-exosomes可改善AMI大鼠的心功能。定量PCR及western blot结果显示,exosomes处理使心肌细胞中Smad7 mRNA和蛋白质的表达水平均上调。结论 huc-exosomes对AMI有修复作用,exosomes可能通过调节Smad7的表达促进细胞修复,Smad7可作为huc-exosomes介导损伤修复的判断指标。Objective To investigate the repair effect of the human umbilical cord mesenchymal stem cell derived exosomes （ huc-exo- somes） for acute myocardial infarction in SD rat and its possible molecular mechanism. Methods We constructed the models of acute myocardial infarction （AMI） in SD rats in vivo. The rats were divided into sham group, AMI plus PBS group and AMI plus exosomes group. The heart function was tested by echocardiography for small animal. The rats were sacrificed at 72h after modelling for obtaining the myocardial tissue, western blot was used to detect the expression of Smad7 in the tissues. In vitro, cardiomyocyte H9C2 and prima- ry myocardial tissue cells were cultured and primary myocardial tissue ceils were identified by immunofluorescence. The myocardial tis- sues were divided into four groups, i. e. , normoxia plus PBS, normoxia plus exosomes, hypoxia plus PBS and hypoxia plus exosomes in hypoxic incubator. The proteins and RNA were extracted from the myocardial cells of each group respectively, and then PCR and western blot were performed to detect the expression changes of Smad7 mRNA and protein. Results We successfully constructed the model of acute myocardial infarction in SD rats. The results of echocardiography showed that heart functions of AMI rat were significant- ly elevated by ejecting exosomes through tail vein. The results of quantitative PCR and Western blot showed that Smad7 mRNA and protein upregulated in the cardiomyocytes treated with exosomes, western blot analysis showed that exosomes treatment also promoted Smad7 protein expression. Conclusion The huc-exosomes may exhibit protective effects for acute myocardial infarction and promote cells repair through regulating Smad7 in cardiomyocyte. Smad7 could be used as an evaluating parameters of huc-exosomes mediated damage repair.

关 键 词：外体 SMAD7 脐带 间充质干细胞 急性心肌梗死 

分 类 号：R542.2[医药卫生—心血管疾病]