血清维生素B12水平对产妇及新生儿IGF2 DNA甲基化的影响

The relationship of serum vitamin B12 and insulin-like growth factor-Ⅱ in maternal and cord blood

目的评价健康产妇血清维生素B12水平对胎儿甲基化状态的影响。方法对河南省侯寨乡中心卫生院80例临产产妇进行回顾性健康问卷调查;采用顺磁性颗粒化学发光免疫法测定血清维生素B12含量;real time-PCR分析IGF2 P2、P3启动子区甲基化状态。结果母亲与脐血血清维生素B12水平分别为167.68 pg/m L和205.98 pg/m L,两组之间差异具有统计学意义(P<0.05)。母血IGF2 P2甲基化率均值为3.03%,脐血3.84%,脐血IGF2 P2甲基化率高于母血IGF2 P2甲基化率(P<0.05)。母血IGF2 P3甲基化率均值为5.58%,脐血为4.35%,母血IGF2 P3甲基化率高于脐血IGF2 P3甲基化率(P<0.05)。脐血IGF2 P3的甲基化状态与母血IGF2P3的甲基化状态呈正相关(β=0.423,P=0.000 5),同时与母血维生素B12水平呈负相关(β=-0.211,P=0.006 9),与母亲受教育程度呈正相关(β=0.185,P=0.038)。母血IGF2 P2的甲基化状态与母血维生素B12水平呈负相关(β=-0.213,P=0.016),与母亲被动吸烟(β=0.310,P=0.022)和孕期增重(β=0.362,P=0.019)呈正相关。结论环境因素可影响母亲外周血及脐血DNA甲基化水平。

Objective To explore the relationship of serum vitamin B12 level and DNA methylation of insulin-like growth factor- Ⅱ. Methods A pilot study was conducted in Houzhai Center Hospital in Zhengzhou, Henan Province Total 80 participants of pregnant women who came to the hospital for delivery were interviewed at the hospital using a standard and structure questionnaire. Serum vitamin B 12 was determined using paramagnetic particle chemiluminescent immunoassay method. The methylation patterns of IGF2 were examined using methylation-specific primer real-time PCR method. Results The average levels of the serum Vit B12 were 167.68 pg mL, and 205.98 pg mL in maternal blood and cord blood respectively. The average levels of IGF2 P2 methylation in maternal blood （3.03 %） was lower than that in cord blood （3.84 %） （P〈0.05）. The average levels of IGF2 P3 methylation in maternal blood （5.58 %） was higher than that in cord blood （4.35 %） （P〈0.05）. Methylation status of IGF2 P3 in cord blood was positively associated with that in maternal blood （β=0.423, P=0.000 5）, inversely associated with serum levels of vitamin B12 in maternal blood （β=-0.211, P=0.006 9）, and positively associated with maternal education level （β= 0.185, P=0.038）. Methylation status in P2 of maternal blood were negatively associated with serum levels of vitamin B12 in maternal blood （β=0.213, P=0.016）, positively associated with exposure to passive smoking （β=0.310, P= 0.022）, and maternal weight gain during pregnancy （β=0.362, P=0.019）. ConclusionsThe study found some humanevidences that environmental factors may effect on methylation status in maternal and cord blood.