胎盘屏障是妊娠期胎儿与母体进行物质交换的主要途径，多种转运体在其中起重要作用。而寡肽转运体介导二/三肽及拟肽类化合物的细胞摄取，可能影响胎儿的营养摄取，但其在胎盘屏障中的表达和功能尚不明确。因此本项目首先采用荧光定量PCR，Western blot方法，进行寡肽转运体在胎盘组织和滋养层细胞中的表达水平和位置的研究，阐明寡肽转运体的表达部位及在胎儿的营养摄取中的作用，以及寡肽转运体作为药物摄取靶标的潜在意义。我们前期研究发现寡肽转运体四个成员在胎盘组织中均有不同程度表达，且PepT2和PhT1在患妊娠期糖尿病产妇的胎盘组织中表达较正常产妇低，因而本项目通过表观遗传修饰研究，揭示妊娠期糖尿病对寡肽转运体在胎盘组织中表达的影响的调控机制。预期成果将揭示寡肽转运体的调控机制以及为妊娠期糖尿病对胎儿的影响提供新的解释。

The human placenta expressed many transport proteins that facilitate the import and efflux of a variety of endogenous substrates and xenobiotics. Proton-coupled oligopeptide transporters (POTs) mediate the cellular uptake of various di/tri-peptides and peptidomimetics, may have an effects on nutrients uptake of fetus. However, the expression and function of POTs in placenta barriers has not been clarified. Real-time PCR and Western blot methods will be used to determine the expression and localization of POTs in placenta tissues and trophoblastic cells, in order to elucidate the function role of POTs in nutrients uptake of fetals. Our previously studied have found that four members of POTs mRNA have different expression level in human placenta, and PepT2 and PhT1 showed lower mRNA expression in placenta with gestational diabetes mellitus (GDM) than healthy placenta. As a result, epigenetic studies will be carried out to clarify the regulation mechanism of GDM on expression of POTs in placenta. Meanwhile, the study will provided reference for clinical effects of GDM on fetus.