miR-22通过靶向UCP2保护心肌细胞免受硫酸吲哚酚诱导的凋亡和过度自噬  

miR-22 protects cardiomyocytes from indole sulfate induced apoptosis and autophagy by targeting UCP2

作　　者：郭影 梁婷 王学忠 Guo Ying;Liang Ting;Wang Xuezhong(Internal Medicine of Heart Center, General Hospital of Ningxia Medical University, Yinchuan 750004)

机构地区：[1]宁夏医科大学总医院心脏中心内科,银川750004

出　　处：《安徽医科大学学报》2022年第1期70-76,共7页Acta Universitatis Medicinalis Anhui

基　　金：宁夏自然科学基金(编号:2020AAC03366)。

摘　　要：目的探讨尿毒症微环境下miRNA-22对心肌细胞凋亡和过度自噬的影响,并阐明该过程的潜在机制。方法收集硫酸吲哚酚(IS)刺激后的H9c2细胞,分别将miR-22模拟物(mimic-miR-22)、miR-22抑制剂(anti-miR-22)和UCP2过表达物(LeUCP2)转染入细胞。采用流式细胞术分析H9c2细胞的存活情况和Western blot分析自噬相关蛋白LC3、p62的表达。结果与接受对照处理的H9c2细胞相比,IS组的存活H9c2细胞数量减少(87.5%vs 56.9%,P<0.01),而凋亡和坏死细胞的数量却增加(6.2%vs 20.6%,6.3%vs 22.5%,P<0.01)。用miR-22模拟物治疗可减少坏死和凋亡细胞的百分比(11.0%vs 20.6%,11.0%vs 22.5%,P<0.05),而用miR-22抑制剂治疗可增加凋亡和坏死细胞的百分比(38.5%vs 20.6%,40.9%vs 22.5%,P<0.01)。Western blot分析显示,miR-22模拟物转染的H9c2细胞与相应的阴性对照miRNA转染的细胞相比具有更低的LC3-Ⅱ/Ⅰ比率[(1.24±0.15)vs(3.26±0.42),P<0.001],而p62蛋白表达提高[(0.92±0.06)vs(0.65±0.05),P<0.05];而miR-22抑制剂则产生了相反的结果[LC3-Ⅱ/Ⅰ比值:(4.53±0.42)vs(3.29±0.40),P<0.01;p62:(0.29±0.04)vs(0.58±0.05),P<0.01]。此外,与空慢病毒载体对照相比,LeUCP2转染导致暴露于IS的H9c2细胞或miR-22抑制剂转染的H9c2细胞中p62表达增加(P<0.05),LC3-Ⅱ/Ⅰ比率降低(P<0.05)。结论miR-22通过靶向UCP2在减轻IS诱导的心肌细胞凋亡和自噬方面起着重要保护作用。Objective To investigate the effect of miRNA-22 on cardiomyocyte apoptosis and autophagy under uremic toxin stimulation and to elucidate the underlying mechanisms of this process.Methods H9c2 cells stimulated by indoxyl sulfate(IS)were collected and transfected with mimic-miR-22,anti-miR-22 and LeUCP2 respectively.Flow cytometry was used to analyze the survival of H9c2 cells,and Western blot was used to analyze the expression of autophagy related proteins LC3 and p62.Results Compared with H9c2 cells subjected to the control treatment,the number of healthy H9c2 cells decreased(87.5%vs 56.9%,P<0.01),while the number of necrotic and apoptotic cells increased(6.2%vs 20.6%,6.3%vs 22.5%,P<0.01)after IS treatment.Treatment with the miR-22 mimics reduced the percentages of necrotic and apoptotic cells(11.0%vs 20.6%,11.0%vs 22.5%,P<0.05),while treatment with the miR-22 inhibitors increased the percentages of necrotic and apoptotic cells(38.5%vs 20.6%,40.9%vs 22.5%,P<0.01).Western blot analysis showed that H9c2 cells transfected with miR-22 mimics exhibited a low LC3-Ⅱ-to-LC3-Ⅰratio[(1.24±0.15)vs(3.26±0.42),P<0.001]but high p62 protein[(0.92±0.06)vs(0.65±0.05),P<0.05]expression compared with cells transfected with corresponding negative control miRNAs;however,miR-22 inhibitors yielded contrasting results[LC3-Ⅱ/Ⅰratio:(4.53±0.42)vs(3.29±0.40),P<0.01;p62:(0.29±0.04)vs(0.58±0.05),P<0.01].In addition,LeUCP2 transfection resulted in an increase in p62 expression(P<0.05)and a decrease in LC3-Ⅱ-to-LC3-Ⅰratio(P<0.05)in H9c2 cells exposed to IS or miR-22 inhibitor-transfected H9c2 cells compared with empty lentivirus vector.Conclusion miR-22 plays an important role in reducing IS induced cardiomyocyte apoptosis and autophagy by targeting UCP2.

关 键 词：硫酸吲哚酚 心肌细胞 miRNA-22 解偶联蛋白2 自噬 

分 类 号：R542.2[医药卫生—心血管疾病]