长链非编码RNA生长停滞特异性转录因子5通过调控铁死亡在急性心肌梗死后心力衰竭中的研究  

Role of lncRNA GAS5in heart failure in rats after acute myocardial infarction by regulating ferroptosis

作　　者：李浩 徐敏 涂清鲜 令狐克强 杨和运 韩骞 Li Hao;Xu Min;Tu Qingxian;Linghu Keqiang;Yang Heyun;Han Qian(Department of Cardiovascular Medicine,Zunyi First People's Hospital·Third Affiliated Hospital of Zunyi Medical University,Zunyi 563000,Guizhou Province,China)

机构地区：[1]遵义市第一人民医院(遵义医科大学第三附属医院)心血管内科,563000 [2]遵义市第一人民医院(遵义医科大学第三附属医院)心电图室,563000

出　　处：《中华老年心脑血管病杂志》2024年第7期824-828,共5页Chinese Journal of Geriatric Heart,Brain and Vessel Diseases

基　　金：遵义市科技局项目[遵市科合HZ(2022)93号];贵州省科技计划项目[黔科合基础-ZK(2022)一般583]。

摘　　要：目的研究心肌细胞铁死亡对急性心肌梗死(AMI)后心力衰竭的影响及其与长链非编码RNA生长停滞特异性转录因子5(lncRNA GAS5)表达的关系。方法选取6~8周龄SD雄性大鼠18只,构建大鼠AMI模型,随机分为空白对照组、假手术组、模型组,每组6只。术后2周心脏彩超检测大鼠心功能,利用氯化三苯四氮唑染色检测大鼠心肌梗死面积,苏木精-伊红染色检测心肌细胞组织病理改变,原位末端标记法检测心肌细胞凋亡情况,铁离子检测试剂盒检测血清铁离子(Fe^(2+))浓度,实时荧光定量聚合酶链反应(QT-PCR)检测心肌组织中lncRNA GAS5、核因子E2相关因子2(Nrf2)、谷胱甘肽过氧化物酶4(GPX4)表达;线性相关性分析lncRNA GAS5、Nrf2、GPX4表达和Fe^(2+)浓度关系,蛋白质免疫印迹(WB)检测心肌组织中铁死亡相关蛋白GPX4、Nrf2、葡萄糖调节蛋白78(GRP78)、半胱氨酸天冬氨酸蛋白酶12(Caspase-12)表达。结果WB检测结果显示,与假手术组比较,模型组心肌组织中促铁死亡相关蛋白GRP78、Caspase-12表达水平显著升高[(1.11±0.13)vs(0.51±0.08),P<0.01;(1.23±0.05)vs(0.92±0.07),P<0.05],铁死亡抑制相关蛋白GPX4、Nrf2表达水平显著降低[(0.27±0.11)vs(0.68±0.10),P<0.01;(0.30±0.12)vs(0.58±0.04),P<0.05]。QT-PCR检测结果显示,与假手术组比较,模型组心肌组织中GPX4 mRNA、Nrf2 mRNA表达水平显著降低(P<0.01),心肌细胞发生铁死亡;QT-PCR检测发现,与假手术组比较,模型组心肌组织中lncRNA GAS5 mRNA表达水平显著升高(P<0.01),且与血清Fe2+浓度呈正相关(P<0.05)。结论AMI与心肌细胞铁死亡的发生密切相关,lncRNA GAS5可能通过Nrf2/GPX4信号通路介导心肌细胞铁死亡在AMI后心力衰竭中的发生。Objective To investigate the impact of cardiomyocyte ferroptosis on acute myocardial infarction(AMI)and its relationship with the expression of long non-coding RNA(lncRNA)GAS5.Methods An AMI model was established in eighteen male SD rats(6-8weeks old),and then the subjected rats were randomly divided into blank control group,sham operation group,and model group,6animals in each group.In 2weeks after surgery,echocardiography was used to evaluate heart function,and TTC staining,HE staining and TUNEL staining were employed respectively to observe myocardial infarct area,histopathological changes of myocardial tissues and apoptosis in cardiomyocytes.Serum Fe^(2+)concentration was measured with an iron ion detection kit.The expression levels of lncRNA GAS5,nuclear factor erythroid-derived 2-like 2(Nrf2),and glutathione peroxidase 4(GPX4)in myocardial tissues were detected with QT-PCR.Linear correlation analysis was performed to investigate the relationship between the expression of lncRNA GAS5,Nrf2and GPX4with Fe^(2+)concentration.Western blotting was conducted for the protein levels of ferroptosis-related proteins,glutathione peroxidase 4(GPX4),nuclear factor erythroidderived 2-like 2(Nrf2),glucose-regulated protein 78(GRP78),and cysteinyl aspartate specific proteinase 12(Caspase-12)in myocardial tissues.Results Western blotting revealed obvious increases in the protein levels of ferroptosis related proteins GRP78(1.11±0.13 vs 0.51±0.08,P<0.01)and Caspase-12(1.23±0.05 vs 0.92±0.07,P<0.05)and a decrease in those of ferroptosis inhibitor GPX4(0.27±0.11 vs 0.68±0.10,P<0.01)and Nrf2(0.30±0.12 vs 0.58±0.04,P<0.05)in the model group than the sham operation group.Additionally,QT-PCR showed that the mRNA levels of GPX4and Nrf2were notably lower,indicating cardiomyocyte ferroptosis,while that of lncRNA GAS5was remarkably higher in the myocardial tissues of the model group than the sham operation group(P<0.01).What's more,the expression of lncRNA GAS5had a positive correlation with serum Fe^(2+)concentration(P<0.05).Co

关 键 词：心肌梗死 心力衰竭 铁死亡 RNA 长链非编码 长链非编码RNA(lncRNA)GAS5 

分 类 号：R541.6[医药卫生—心血管疾病] R542.22[医药卫生—内科学]