高同型半胱氨酸血症对ApoE^(-/-)鼠心脏内质网应激的影响  

The effects of hyperhomocysteinemia on myocardial endoplasmic reticulum stress in ApoE^(-/-) mice

作　　者：周龙霞[1] 赵丽[2] 陈久凯 杨安宁[1] 刘现梅 王艳华[2] 姜怡邓[1] 曹军[1] 

机构地区：[1]宁夏医科大学基础医学院 [2]宁夏医科大学检验学院,银川750004

出　　处：《广东医学》2015年第7期981-984,共4页Guangdong Medical Journal

基　　金：国家自然科学基金资助项目(编号:81260063)

摘　　要：目的探讨高同型半胱氨酸血症(HHcy)对Apo E-/-鼠心脏内质网应激(ERS)的影响及其可能机制。方法取5周龄雄鼠12只作为正常对照组;另取5周龄雄性Apo E-/-小鼠36只,随机分为3组,Apo E-/-对照组:Apo E-/-小鼠饲以普通饲料配方饮食;高蛋氨酸组:Apo E-/-小鼠饲以高蛋氨酸饮食;干预组:Apo E-/-小鼠饲以高蛋氨酸饮食同时加0.006%叶酸和0.000 4%维生素B12。喂养20周后处死,行主动脉病理切片HE染色观察主动脉是否有斑块形成;取心脏,采用实时荧光定量PCR法检测GRP78、CHOP、Caspase-12 mRNA的变化;巢式降落式甲基化特异性PCR检测GRP78和CHOP启动子区DNA甲基化水平。结果正常对照组及Apo E-/-对照组斑块不明显,高蛋氨酸组动脉粥样硬化斑块面积明显增大,主动脉内膜可见灶性病变部位隆起突入动脉腔内,干预组动脉粥样硬化斑块面积较高蛋氨酸组有所减轻。与Apo E-/-对照组比较,高蛋氨酸组GRP78、CHOP、Caspase-12 mRNA水平明显升高(P<0.05,P<0.01),干预组GRP78、CHOP mRNA水平较高蛋氨酸组降低(P<0.05)。与Apo E-/-对照组比较,高蛋氨酸组GRP78、CHOP启动子区DNA甲基化水平降低(P<0.01),干预组GRP78、CHOP甲基化水平较高蛋氨酸组有所升高(P<0.05)。结论 HHcy可能通过影响DNA甲基化程度引起ERS相关基因表达改变,进而导致心肌细胞凋亡,补充叶酸与维生素B12可有效缓解HHcy所引起的ERS和凋亡。Objective To investigate the effects of hyperhomocysteinemia （ HHcy ） on myocardial endoplasmic reticulum stress （ ERS） in ApoE-/-mice and its possible mechanism.Methods Thirty-six 5 -week old ApoE-/-C57BL/6J mice were randomly divided into three groups, including ApoE-/-control group, ApoE-/-HHcy group and the intervention group.Twelve 5-week old normal C57BL/6J mice were served as normal group.After 20 weeks of feed-ing, the aortae were separated for HE stain and observation of aortic plaque.GRP78, CHOP and Caspase-12 mRNA lev-els were determined by qRT-PCR.The methylation status of GRP78 and CHOP were studied using the nest touch down methylation specific polymerase chain reaction （ ntMS-MSP） .Results No significant aortic plaque was observed in ei-ther normal group or ApoE-/-control group.In the ApoE-/-HHcy group, the aortic plaque areas were greater, breaking into the aortic lumina, which were alleviated in the intervention group.The mRNA levels of GRP78, CHOP and Caspase-12 in the ApoE-/-HHcy group were significantly higher than those in ApoE-/-control group（P＜0.05,P＜0.01）, while they were significantly down-regulated in the intervention group（P＜0.05,P＜0.01）.GRP78 and CHOP DNA methylation levels were significantly lowered in the ApoE-/-HHcy group（P＜0.01,P＜0.01）,while significanty higher in the intervention group（P＜0.05,P＜0.05）.Conclusion HHcy may affect Myocardial ERS via changing DNA methy-lation levels, then lead to apoptosis.Earlier folic acid and VB12 interference can effectively reduce the myocardial ERS and apoptosis.

关 键 词：高同型半胱氨酸血症 内质网应激 葡萄糖调节蛋白78 C/EBP环磷酸腺苷反应元件结合转录因子同源蛋白 胱冬酶-12 

分 类 号：R589.3[医药卫生—内分泌]