不同氧化态叶酸对人成淋巴细胞系基因组DNA甲基化水平的影响  

Effects of Folate with Different Oxidative States on Genomic DNA Methylation in Human Lymphoblast Cell Line

作　　者：倪娟[1] 陈海燕[1] 曹能[1] 周滔[1] 薛京伦[2] 汪旭[1] 

机构地区：[1]云南师范大学生命科学学院,昆明650500 [2]复旦大学遗传学研究所

出　　处：《肿瘤防治研究》2014年第3期256-259,共4页Cancer Research on Prevention and Treatment

基　　金：国家自然科学基金资助项目(30960166;31260268);云南省科技基金资助项目(2010ZC065)

摘　　要：目的比较最高氧化态叶酸(folic acid,FA)与还原态5-甲基四氢叶酸(5-methyltetrahydrofolate,5-MeTHF)对人成淋巴细胞LINE-1和Alu的甲基化效应,从而评价受试物对全基因组DNA甲基化的影响。方法以含30、60和120 nmol/L FA或5-MeTHF的改良RPMI1640培养液干预培养人成淋巴细胞系GM12593,20 d后提取基因组DNA,用亚硫酸盐修饰测序法(BSP)比较不同浓度和氧化态叶酸对受试细胞Alu和LINE-1甲基化水平的影响。结果基因组Alu和LINE-1甲基化水平均随FA或5-MeTHF浓度的升高而增加,两目标序列的甲基化水平在120 nmol/L FA或5-MeTHF浓度下显著高于30和60 nmol/L组(P【0.01~0.05),60和120 nmol/L的5-MeTHF提高LINE-1甲基化水平的能力显著高于同等浓度的FA(P【0.01~0.05)。结论 FA和5-MeTHF浓度与人成淋巴细胞基因组DNA甲基化水平显著正相关,5-MeTHF的基因组甲基化维护效应强于FA。Objective To explore the effects of the highest oxidized folate(folic acid, FA) and reduced active folate(5-methyltetrahydrofolate, 5-MeTHF) on the methylations of LINE-1 and Alu, which were able to serve as surrogate markers for global genomic DNA methylation. Methods Human lymphoblast cell line GM12593 was cultured in the modifi ed RPMI1640 nutrient solutions containing either 30, 60 and 120 nmol/L FA or 5-MeTHF. Bisulfi te sequencing PCR was employed to detect the methylation status of Alu and LINE-1 after 20 days. Results The methylation levels of Alu and LINE-1 were increased with the concentrations increasing of FA or 5-MeTHF and were signifi cantly higher at 120 nmol/L of FA or 5-MeTHF than those at 30 or 60 nmol/L(P < 0.01-0.05). The methylation levels of LINE-1 at 60 and 120 nmol/L of 5-MeTHF groups were signifi cantly higher than that of FA. Conclusion There was a positive correlation between FA or 5-MeTHF and human genomic DNA methylation. 5-MeTHF was more effi cient on the methylation profi le maintaining than FA in human lymphoblast cell line.

关 键 词：叶酸 基因组DNA甲基化 ALU LINE-1 

分 类 号：R341[医药卫生—基础医学]