中文摘要：

目的：检测正常妊娠及妊娠期糖尿病患者胎盘及血清中microRNA518d（miR-518d）的表达,探讨其在妊娠期糖尿病发病及诊断中的作用。方法：选择无妊娠并发症和合并症的足月剖宫产分娩产妇20例及妊娠期糖尿病足月剖宫产分娩产妇20例。分别收集两组的新鲜胎盘组织及母体血清,用Taqman实时荧光定量PCR方法检测两组miRNAs的变化。结果：miR-518d在妊娠期糖尿病胎盘中的表达（4.35 ± 0.88）显著高于对照组（1.04 ± 0.73）（P ＜ 0.01）,而其在妊娠期糖尿病血清中的表达水平（2.43 ± 1.07）也明显高于对照组（0.96 ± 0.88）（P ＜ 0.05）,生物信息学预测过氧化物酶体增殖物激活受体α（PPARα）3′UTR区含有miR-518d的结合位点,且胎盘miR-518d表达水平和血清雌二醇水平呈正相关（R2 = 0.759,r = 0.871）。结论：miR-518d可能通过调控PPARα基因参与妊娠期糖尿病的发病,有望成为妊娠期糖尿病的潜在诊断指标。

英文摘要：

Objective：To investigate the expression level of miR-518d in the placenta and maternal serum of gestational diabetes mellitus and normal pregnant women. Methods：The expression of miR-518d in placenta and serum was measured by Taqman RT-PCR in 20 women with GDM and 20 women with normal term pregnancy. Results：Expression of miR-518d in placenta was significantly up-regulated in GDM group（4.35 ± 0.88）compared to control group（1.04 ± 0.73）（P 〈 0.01）. Expression of miR-518d in serum was also up-regulated in GDM group（2.43 ± 1.07）compared to control group（0.96 ± 0.88）（P 〈 0.05）. We also showed that PPARa was a direct target of miR-518d with a specific binding site at the seed sequence. And expression of miR-518d in the placenta was significantly positive correlated with the expression of serum E2（R2=0.759,r = 0.871）. Conclusion：miR-518d is related with the mechanism of GDM and we suggest that upregulation of miR-518d may be associated with the pathogenesis of GDM via an effect on the regulation of PPARα expression.