酒精致小鼠胚胎心脏组蛋白H3K9高乙酰化失衡及其表突变  

Hyperacetylation imbalance and epimutation of H3K9 induced by alcoholconsumed during gestation in mice

作　　者：潘博[1] 孙慧超[1] 吕铁伟[1] 吴晓云[1] 朱静[1] 田杰[1] 

机构地区：[1]重庆医科大学附属儿童医院心血管内科与小儿心血管病学研究室儿童发育疾病研究省部共建教育部重点实验室重庆市儿童发育重大疾病诊治与预防国际科技合作基地儿科学重庆市重点实验室,重庆400014

出　　处：《临床心血管病杂志》2013年第5期395-398,共4页Journal of Clinical Cardiology

基　　金：973基金资助(No:2010CB529504);国家自然科学基金资助(No:81270234);重庆市渝中区科技计划项目(2012)

摘　　要：目的:揭示小鼠胚胎心脏发育过程中组蛋白H3K9乙酰化水平的时序性,阐明孕期饮酒对胚胎心脏组蛋白H3K9乙酰化及胚胎心脏发育相关基因表达的影响,并探讨其机制。方法:选择清洁级健康成年昆明小鼠60只,于孕期E7.5～E15.5连续予以10μl.g-1.d-1、56%的饮用白酒连续灌胃作为酒精干预组,0.9%氯化钠溶液灌胃作为对照组。取E11.5、E14.5、E17.5孕鼠及新生小鼠心脏作为标本,利用Western blot观察正常小鼠胚胎心脏发育过程中组蛋白H3K9乙酰化水平的时序表达规律以及酒精干预后的变化;实时定量PCR检测心脏发育相关基因Mef2c和GATA4的mRNA表达。结果:小鼠胚胎心脏发育过程中,组蛋白H3K9乙酰化水平于发育早期(E11.5)开始升高,E17.5达到高峰,而新生时期降至较低水平;E17.5较E11.5和新生期均差异有统计学意义(均P<0.05)。酒精干预组E11.5、E14.5及E17.5的胚胎心脏组蛋白H3K9乙酰化水平较对照组分别升高2.35、1.47及1.56倍(均P<0.05)。同时,酒精干预组E14.5、E17.5的GATA4mRNA表达较对照组分别升高1.98、1.55倍(均P<0.05),而E14.5的Mef2cmRNA表达较对照组升高2.08倍(P<0.05)。结论:正常小鼠胚胎心脏发育过程中组蛋白H3K9乙酰化水平于早期开始升高,E17.5达到高峰,而新生时期下降至较低水平。孕期饮酒可导致胚胎心脏组蛋白H3K9高乙酰化失衡和心脏发育相关基因Mef2c、GATA4表达异常。Objective：To investigate the epigenetic mechanism of cardiac developmental abnormalities induced by alcohol consumption during gestation in mice. Method：Sixty KM mice at 6 to 8 weeks were mated at 5∶00 pm and females were examined for a vaginal plug in the following morning.The noon of the day when a vaginal plug was confirmed would be considered as E0.5.The pregnant mice were exposed to a single dose of alcohol（10 μl·g^1·d^-1% alcohol） by gavage between E7.5-E15.5.Embryonic hearts of E11.5,E14.5 and E17.5 of the fetal mice and heats of the newborn mice were collected respectively.Western blot was used for detecting the level of H3K9 acetylation during the embryonic heart development and the imbalanced change induced by alcohol.The mRNA expression of the heart development-related genes（Mef2c,GATA4） were measured by Q-PCR method. Result：The level of histone H3K9 acetylation reached peak at E17.5 and decreased sharply to a significantly lowlevel at newborn.Alcohol exposure increased histone H3K9 acetylation at E11.5,E14.5 and E17.5 by 2.35,1.47 and 1.56 folds,respectively（P〈0.05）.Moreover,alcohol consumed during gestation significantly augmented the expression of GATA4 by 1.98 and 1.55 folds at E14.5 and E17.5,respectively（P〈0.05）.Meanwhile,the expression of Mef2c increased by 2.08 folds at E14.5 caused by alcohol exposure（P〈0.05）. Conclusion：The level of histone H3K9 acetylation reaches peak at E17.5 and decreases sharply to a significantly low level at newborn.Alcohol consumed in pregnant mice can induce the hyperacetylation of H3K9 and cause the anomalous expression of heart development-related genes（Mef2c and GATA4）.

关 键 词：心脏发育 酒精 组蛋白乙酰化 表突变 心脏发育相关基因 

分 类 号：R541.1[医药卫生—心血管疾病]