阿霉素损伤心肌细胞miRNA378与网腔钙结合蛋白、内质网应激的关系

目的：研究阿霉素损伤心肌细胞miRNA378与网腔钙结合蛋白（calumenin）、内质网应激相关性。方法：原代培养乳鼠心肌细胞分为6组：对照组、阿霉素组、miRNA378过表达对照组、miRNA378过表达组、miRNA378沉默对照组、miRNA378沉默组，采用免疫组化法检测细胞α-SMA蛋白；慢病毒质粒转染心室肌细胞，实时荧光定量PCR技术检测各组心肌细胞miRNA378、calumenin及葡萄糖调节蛋白78（GRP78） mRNA表达。结果：与阿霉素组相比较，miRNA378过表达组心肌细胞calumenin mRNA表达增加（P<0.01），而GRP78 mRNA表达减少（P<0.01）；与阿霉素组相比较，miRNA378沉默组calumenin及GRP78 mRNA表达无统计学差异。结论：阿霉素损伤乳鼠心肌细胞是通过减少calumenin蛋白表达进而引起内质网应激，该作用通过上调miRNA378得到缓解。

The relationship between miRNA378, calumenin and endoplasmic reticulum stress in suckling mouse myocardium with myocarditis caused by adriamycin

Objective: To investigate the relationship between miRNA378, calumenin and endoplasmic reticulum stress in suckling mouse myocardium with myocarditis caused by adriamycin. Methods: The suckling mouse myocardium of primary culture were randomly divided into control group, adriamycin group, lentivirus infection miRNA378 over expression control group, lentivirus infection miRNA378 over expression group, lentivirus infection miRNA378 silence control group and lentivirus infection miRNA378 silence group. Firstly to identify the suckling mouse myocardium, α-SMA was monitored by immunohistochemical method, and secondly the ventricular myocytes were transfered by lentivirus plasmids. Then the expression change of miRNA378, calumenin and glucose regulated protein 78(GRP78) mRNA were detected by Quantitative Real-time PCR. Results: Compared with the adriamycin infection group, the expression of calumenin mRNA in lentivirus infection miRNA378 over expression group was increased(P<0.01), while the expression of GRP78 mRNA was reduced(P<0.01); Compared with the adriamycin infection group, the expressions of calumenin and GRP78 mRNA in lentivirus infection miRNA378 silence group did not change insignificantly. Conclusion: Adriamycin injection may cause expression of calumenin in suckling mouse myocardium with myocarditis reduced, which may lead to the endoplasmic reticulum stress. This effect is related with miRNA378.