转录因子EB在病毒性心肌炎B细胞中的表达及机制研究

Study on the expression of transcription factor EB in viral myocarditis B cells and its mechanism

目的:初步探究转录因子EB(TFEB)在病毒性心肌炎(VMC)B细胞中的表达和机制。方法:将小鼠随机分为VMC组和对照组,VMC组小鼠腹腔注射CVB3建立急性VMC小鼠模型,对照组小鼠同一天腹腔注射相同剂量的PBS,观察两组小鼠的心肌损伤变化;采用免疫印迹分析方法(Western blotting)检测两组B细胞中TFEB的表达和自噬标记物LC3Ⅱ/LC3Ⅰ相对表达量;体外培养从VMC小鼠中分离的脾脏B细胞,分为VMC+Tre组和VMC组,VMC+Tre组加入自噬诱导剂,VMC组加PBS作为对照,Western blotting检测两组B细胞中的TFEB蛋白的表达和LC3Ⅱ/LC3Ⅰ相对表达量。结果:与对照组对比,VMC组小鼠心肌炎症细胞浸润,心肌病理积分、B细胞中的TFEB表达水平及自噬标志物LC3Ⅱ/LC3Ⅰ相对表达量增高(均P<0.05);与VMC组B细胞相比较,VMC+Tre组小鼠B细胞中的TFEB蛋白相对表达量、LC3Ⅱ/LC3Ⅰ相对表达量增高,同时,LC3Ⅱ/LC3Ⅰ相对表达量与TFEB蛋白相对表达量呈正相关关系(均P<0.05)。结论:病毒性心肌炎B细胞中TFEB表达增加,其可能与病毒性心肌炎B细胞的自噬增强相关。

Objective:To preliminarily investigate the expression of transcription factor EB(TFEB)in viral myocarditis(VMC)B cells and its mechanism.Methods:Mice were randomly divided into VMC group and control group.The VMC group mice were injected intraperitoneally with coxsackie virus B3(CVB3)to establish a mouse model of acute VMC while the control group mice were injected intraperitoneally with the same volume of PBS on the same day.The changes of myocardial injury in both groups were observed.The expression of TFEB in B cells of both groups and the relative expression of autophagy marker LC3Ⅱ/LC3Ⅰwere detected by western blotting.Splenic B cells isolated from VMC mice were cultured in vitro and divided into VMC+Tre group and VMC group.Autophagy inducer was added to VMC+Tre group and PBS was added to VMC group as control,and the expression of TFEB and the relative expression of LC3Ⅱ/LC3Ⅰwere detected by western blotting in B cells of both groups.Results:Compared with the control group,myocardial inflammatory cell infiltration,myocardial pathological score,TFEB expression level in B cells and relative expression of autophagy marker LC3Ⅱ/LC3Ⅰwere increased in the VMC group(P<0.05).Compared with the VMC group,the expression of TFEB protein and LC3Ⅱ/LC3Ⅰ in B cells were increased in the VMC+Tre group,and the LC3Ⅱ/LC3Ⅰwas positively correlated with TFEB protein(P<0.05).Conclusion:TFEB expression is increased in VMC B cells,which may be related to the enhanced autophagy of VMC B cells.