摘要
目的:探讨IRX1甲基化在心力衰竭(HF)大鼠中的作用机制。方法:通过生物信息学分析选择HF大鼠心肌细胞中的靶基因;通过TAC手术构建HF实验大鼠模型,并分组为假手术组(Sham组)、TAC组、Sham+5-Aza组和TAC+5-Aza组。通过心脏超声检测大鼠心脏功能,免疫组织化学染色评价心脏损伤程度;GSEA分析功能基因的相对丰富度。通过免疫荧光分析、Western blotting和qRT-PCR检测DNA甲基化和表达水平。结果:与正常人的基因组相比,HF患者基因组中甲基化程度显著提高,生物信息学分析确定IRX1为靶基因,IRX1表达与CXCL14/NF-κB之间存在显著相关性。超声心动图评估HF大鼠心脏功能的结果显示,与TAC组相比,TAC+5-Aza组的左心室与体重的比率显著降低,而LVDP、dP/dtmax和EF显著增加(P<0.01)。免疫染色结果显示,与TAC组相比,TAC+5-Aza组心肌细胞排列紊乱的情况得到有效缓解并恢复正常心肌细胞状态。qRT-PCR及Western blotting结果显示,与TAC组相比,TAC+5-Aza组大鼠的基因组DNA甲基化、IRX1甲基化、左心室ANP、BNP基因和β-MHC m RNA的表达水平显著降低(P<0.01),α-MHC m RNA的表达水平、IRX1和CXCL14的m RNA和蛋白表达水平以及MMP9和C-FLIP蛋白表达水平显著增加(P<0.01)。心肌纤维化和心肌细胞凋亡实验结果显示,与TAC组相比,TAC+5-Aza组大鼠心肌纤维化和心肌细胞凋亡阳性率显著降低(P<0.01)。结论:HF模型大鼠的IRXI甲基化水平提高可能激活CXCL14/NF-κB表达,以改善TAC诱导的心肌纤维化和细胞凋亡情况。
Objective: To investigate the mechanism of IRX1 methylation in heart failure(HF) rats. Methods: Selection of target genes in HF rat cardiomyocytes by bioinformatics analysis, and HF experimental rat models were established by TAC operation, and the experiment was divided into four groups(Sham operation group(Sham group), TAC group, Sham+5-Aza group and TAC+5-Aza group).Cardiac function was detected by echocardiography, and the degree of cardiac injury was evaluated by immunohistochemistry. The relative abundance of functional genes was analyzed by GSEA. DNA methylation and expression were detected by immunofluorescence,Western blotting and qRT-PCR. Results: Compared with normal human genome, the methylation level of HF heart failure genome was significantly increased. Bioinformatics analysis confirmed that IRX1 was the target gene, and there was a significant correlation between IRX1 expression and CXCL14/NF-κB. Compared with TAC group, the ratio of left ventricle to body weight in TAC+5-Aza group was significantly lower, while LVDP, DP/dtmax and EF were significantly increased(P<0.01). Compared with TAC group, the disorder of cardiomyocyte arrangement was effectively alleviated and normal cardiomyocyte state was restored in TAC+5-Aza group. The results of qRT-PCR and Western blotting showed that compared with TAC group, DNA methylation, IRX1 methylation, ANP, BNP gene andβ-MHC m RNA expression levels of rats in TAC+5-Aza group were significantly lower than those in TAC group(P<0.01);and compared with TAC group, α-MHC m RNA expression level, IRX1 and CXCL14 m RNA and protein expression levels, MMP9 and c-FLIP protein expression levels were significantly increased(P<0.01). Then, compared with TAC group, the positive rates of myocardial fibrosis and cardiomyocyte apoptosis in TAC+5-Aza group were significantly decreased(P<0.01). Conclusion: The increased level of IRXI methylation in HF model rats may activate the expression of CXCL14/NF-κB to protect myocardial fibrosis and apoptosis induced by TAC.
作者
闫莉
刁佳宇
邓纪钊
梁健
杨光
YAN Li;DIAO Jia-yu;DENG Ji-zhao;LIANG Jian;YANG Guang(nd Department of Cardiovascular Medicine,Shaanxi Provincial People's Hospital,Xi'an,Shaanxi,710068,China)
出处
《现代生物医学进展》
CAS
2021年第14期2626-2632,共7页
Progress in Modern Biomedicine
基金
陕西省自然科学基础研究计划项目(2020JM-665)。
