糖氧剥夺对大鼠心肌细胞中常染色质组蛋白赖氨酸甲基转移酶2与脑源性神经营养因子表达水平的影响  

Influence of oxygen-glucose deprivation on the expression of euchromatic histone methyltransferase 2 and brain-derived neurotrophic factors in rat cardiomyocytes

作　　者：闫芳[1] 廖红娟[1] 薛正龙 刘自宁 步纪强 赵腾月 王冰洁 YAN Fang;LIAO Hongjuan;XUE Zhenglong;LIU Zining;BU Jiqiang;ZHAO Tengyue;WANG Bingjie(Department of Cardiac Surgery,the Second Hospital of Hebei Medical University,Shijiazhuang 050000,Hebei Province,China;Department of Anesthesiology,the Third Hospital of Hebei Medical University,Shijiazhuang 050000,Hebei Province,China)

机构地区：[1]河北医科大学第二医院心脏外科,河北石家庄050000 [2]河北医科大学第三医院麻醉科,河北石家庄050000

出　　处：《新乡医学院学报》2025年第5期345-350,共6页Journal of Xinxiang Medical University

基　　金：河北省医学科学研究课题计划(编号:20240910)。

摘　　要：目的探讨糖氧剥夺(OGD)对大鼠心肌细胞中常染色质组蛋白赖氨酸甲基转移酶2(EHMT2,亦称G9a)与脑源性神经营养因子(BDNF)表达水平的影响。方法将H9C2大鼠心肌细胞随机分为对照组、OGD组。对照组细胞行常规培养。OGD组细胞接种于无血清达尔伯克改良伊格尔培养基(DMEM)中,置于37℃、含体积分数95%N2和5%CO_(2)的厌氧室培养6 h;然后将培养基更换为含体积分数10%胎牛血清的DMEM,并将细胞置于37℃、含体积分数5%CO_(2)培养箱中培养12 h,进行OGD处理。取生长良好的OGD组细胞,随机分为阴性对照组(sh-NG组)和sh-G9组,使用脂质体2000转染试剂盒分别转染已构建好sh-NG和sh-G9a。采用反转录定量聚合酶链式反应分别检测对照组和OGD组、sh-NG和sh-G9a组细胞中G9a、BDNF及组蛋白H3第9位赖氨酸二甲基化(H3K9me2)mRNA的表达情况;采用蛋白质印迹法检测对照组和OGD组细胞中G9a蛋白的表达情况及对照组、OGD组、sh-NG组和sh-G9a组细胞中BDNF、H3K9me2蛋白的表达情况。应用染色质免疫沉淀实验检测sh-NG组和sh-G9a组细胞中BDNF启动子上H3K9me2的相对表达量。结果与对照组相比,OGD组细胞中G9a、H3K9me2 mRNA的相对表达量均显著升高(t=10.638、14.549,P<0.05),BDNF mRNA的相对表达量显著降低(t=9.406,P<0.05)。与sh-NG组相比,sh-G9a组细胞中G9a、H3K9me2 mRNA的相对表达量均显著降低(t=8.317、8.531,P<0.05),BDNF mRNA的相对表达量显著升高(t=12.125,P<0.05)。与对照组相比,OGD组细胞中G9a蛋白的相对表达量显著升高(t=9.683,P<0.05),BDNF蛋白相对表达量显著降低(t=10.712,P<0.05);sh-NG组与OGD组细胞中BDNF蛋白相对表达量比较差异无统计学意义(t=34.752,P>0.05);与OGD组相比,sh-G9a组细胞中BDNF蛋白相对表达量显著升高(t=8.831,P<0.05)。与对照组相比,OGD组细胞中H3K9me2蛋白相对表达量显著升高(t=9.774,P<0.05);sh-NG组与OGD组细胞中H3K9me2蛋白相对表达量比较差异无统计学意义Objective To study the influence of oxygen-glucose deprivation(OGD)on the expression of euchromatic histone methyltransferase 2(EHMT2,also known as G9a)and brain-derived neurotrophic factors(BDNFs)in rat cardiomyocytes.Methods H9C2 rat cardiomyocytes were randomly divided into a control group and an OGD group.Cells in the control group were cultured routinely.Cells in the OGD group were first seeded in a serum-free Dulbecco′s modified Eagle′s medium(DMEM)and then cultured 6 hours in an anaerobic chamber containing 95%N 2 and 5%CO 2.After the culture medium was replaced with a DMEM containing 10%fetal bovine serum,the cells were cultured 12 hours in an incubator containing 5%CO 2 at 37℃for OGD treatment.Well-grown cells in the OGD group were taken and divided into a negative control group(sh-NG)and a sh-G9a group,into which the constructed sh-NG and sh-G9a cells were transfected using the liposome 2000 transfection kit,respectively.Reverse transcription quantitative polymerase chain reaction(RT-qPCR)was used to detect the expression of G9a,BDNF,and histone H3 lysine 9 dimethylation(H3K9me2)mRNAs in control,OGD,sh-NG and sh-G9a groups.Western blotting was used to detect the expression of G9a proteins in control and OGD groups and the expression of BDNF and H3K9me2 proteins in control,OGD,sh-NG and sh-G9a groups.Chromatin immunoprecipitation sequencing was used to measure the relative expression levels of H3K9me2 on the BDNF promoter in sh-NG and sh-G9a groups.Results Compared with those in the control group,the relative expression levels of G9a and H3K9me2 mRNAs were significantly increased(t=10.638,14.549,P<0.05)and the relative expression level of BDNF mRNAs was significantly decreased in the OGD group(t=9.406,P<0.05).The relative expression levels of G9a and H3K9me2 mRNAs were significantly lower(t=8.317,8.531,P<0.05)while the relative expression level of BDNF mRNAs was significantly higher(t=12.125,P<0.05)in the sh-G9a group than those in the sh-NG group.The relative expression level of G9a proteins was s

关 键 词：心脏细胞 常染色质组蛋白赖氨酸甲基转移酶2 脑源性神经营养因子 糖氧剥夺 

分 类 号：R541.6[医药卫生—心血管疾病]