摘要
目的探索甲基转移酶样14(METTL14)介导的N6-甲基腺苷(m6A)修饰在心肌梗死(MI)中的生物学作用。方法将小鼠随机分为4组,每组10只:Sham+AAV9-NC组、Sham+AAV9-METTL14组、MI+AAV9-NC组和MI+AAV9-METTL14组。各组小鼠分别在MI诱导前1周将AAV9-METTL14或AAV9-NC通过尾静脉注射到小鼠体内。通过经胸超声心动图无创测量心脏功能,并采用免疫荧光测定小鼠微血管损伤和内皮线粒体功能障碍。从小鼠心肌组织中分离CMECs,对细胞进行去氧葡萄糖(OGD)处理。结果METTL14在MI小鼠心脏组织以及OGD处理的CMECs中下调。与Sham+AAV9-NC组小鼠相比,MI+AAV9-NC组小鼠中VE-cadherin表达显著下调(P<0.05),线粒体ROS水平显著增加(P<0.05)。MI+AAV9-METTL14抑制了这些变化,并增强了小鼠的心脏功能。与NC组相比,在OGD组CMECs细胞中观察到线粒体ROS水平显著增加(P<0.05)。CMECs细胞中METTL14敲低加剧了ROS水平(P<0.05),当加入USP48过表达质粒则逆转了这些变化(P<0.05)。结论METTL14在MI中低表达,并通过增加CMECs细胞USP48的m6A修饰水平以降低其稳定性,从而介导CMECs细胞线粒体功能障碍。
Objective To investigate the biological role of methyltransferase-like 14(METTL14)-medi⁃ated m6A modification in myocardial infarction(MI).Methods A total of 40 mice were randomly divided into 4 groups:Sham+AAV9-NC group(n=10),Sham+AAV9-METTL14 group(n=10),MI+AAV9-NC group(n=10)and MI+AAV9-METTL14 group(n=10).Mice in each group were injected with AAV9-METTL14 or AAV9-NC through the tail vein one week before MI induction.Cardiac function was measured non-invasively by transthoracic echocardiography,and microvascular injury were measured by immunofluorescence.CMECs were isolated from mouse myocardial tissue,and the cells were treated with oxygen-glucose deprivation(OGD).Results METTL14 was downregulated in MI mouse heart tissue as well as in OGD-treated CMECs.Compared with the Sham+AAV9-NC group,the expression of VE-cadherin was significantly down-regulated(P<0.05),ROS levels increased signifi⁃cantly(P<0.05)in the MI+AAV9-NC group.MI+AAV9-METTL14 suppressed these changes and enhanced cardiac function in mice.Compared with the NC group,a significant increase in mitochondrial ROS levels was observed in the OGD group(P<0.05).Knockdown of METTL14 in CMECs exacerbated ROS levels(P<0.05),and the addition of USP48 overexpression plasmid reversed these changes(P<0.05).Conclusion METTL14 was lowly expressed in MI and mediates mitochondrial dysfunction in CMECs by increasing the m6A modification level of USP48 in CMECs to reduce its stability.
作者
郑学斌
沙莎
杨慧琼
刘恋
ZHENG Xuebin;SHA Sha;YANG Huiqiong;LIU Lian(Department of General Practice,Changsha Fourth Hospital(Changsha Hospital Affiliated to Hunan Normal University),Changsha 410006,China)
出处
《实用医学杂志》
CAS
北大核心
2023年第21期2754-2760,共7页
The Journal of Practical Medicine
基金
湖南省卫生健康委员会科研项目(编号:20210278)。
