宫内发育迟缓对印记基因胰岛素样生长因子-2/过氧化物酶体增生物激活受体γ共激活因子1α基因表达的影响

Influence of intrauterine growth retardation on imprinted gene IGF-2/PGC-1α

目的研究新生儿胎盘组织中印记基因IGF-2和PGC-1α的甲基化和mRNA的表达水平,探讨印记基因与宫内发育迟缓的相关性。方法收集无妊娠期并发症及无胎盘脐带异常的足月儿新鲜胎盘共40例,其中正常出生体质量儿20例为对照组、足月小样儿20例为实验组,采用基因组DNA亚硫酸氢钠处理后直接测序法和实时荧光定量PCR方法检测以上标本中IGF-2和PGC-1α基因甲基化和mRNA的表达。结果实验组IGF-2和PGC-1α的基因甲基化的表达比对照组增高,mRNA表达水平较对照组降低,差异均有统计学意义(P<0.05)。出生体质量与IGF-2和PGC-1αmRNA在胎盘中的表达呈正相关(r值分别为0.79、0.87,P<0.01)。结论宫内发育迟缓影响印记基因IGF-2和PGC-1α的表达,这2个基因可能作为修饰的靶点,从而对宫内发育迟缓胎儿进行早期的干预。

Objective To study the expression of the imprinted gene IGF-2 and PGC-1α in newborn placenta,and to discuss the relationship between intrauterine growth retardation and imprinted gene. Methods The fresh placental tissues were collected from full-term newborn（ without trimester of pregnancy complication and placenta and funic abnormality） in the control group（ 20 cases） and low birth body mass in the treatment group（ 20 cases）. After the processing with genetic DNA sodium bisulfite,the expressions of imprinted gene IGF-2,PGC-1α and mRNA were measured by real-time fluorescence quantitative PCR. Results The methylation status of IGF-2 and PGC-1α in treatment group was significantly higher than that in the control group,while the mRNA expression in treatment group was significantly lower than that in the control group,with the differences statistically significant（ P〈0. 05）. The birth body mass was positively correlated to the expression of IGF-2 and PGC-1α mRNA（ r = 0. 79,r = 0. 87,P 〈0. 01）. Conclusion Imprinted IGF-2 and PGC-1α expression was effected by intrauterine growth retardation which could be the targets of modification,so as to early intervene the fetus of intrauterine growth retardation.