Research of endocrine regulation of the invasive potential and apoptosis extravillous trophoblasts

本研究旨在确定T_3受体是否存在于早期胎盘绒毛外滋养细胞（evt）中，并评估T_3对培养的早期胎盘evt中Fas/Fas配体表达、caspase-3和聚（adp -核糖）聚合酶（PARP）裂解和凋亡的影响。早期胎盘EVTs表达一个212 bp的c- erbb a - β1转录物和T_3受体蛋白，并在培养中表现出显著的凋亡水平。T_3可降低体外培养evt中Fas和Fas配体的表达、caspase-3和PARP的裂解，抑制细胞凋亡。这些结果表明，T_3受体存在于胎盘早期evt中，并且T_3通过下调Fas和Fas配体的表达来抑制细胞凋亡。此外，为了探讨T_3在EVT侵袭蜕膜中的可能作用，我们检测了T_3是否影响EVT侵袭电位以及培养的早期胎盘EVT中基质金属蛋白酶-2 （MMP-2）、MMP-3、组织抑制剂金属蛋白酶-1、胎儿纤维连接蛋白（FN）和整合素α_5β_1的表达。Matrigel侵袭试验表明，T_3处理显著增加了培养evt的细胞投射数量。RT-PCR分析显示，T_3处理增加了培养evt中MMP-2、MMP-3、胎儿FN和整合素α_5β_1 mRNA的表达。免疫细胞化学和Western免疫印迹分析显示，T_3可提高培养evt中MMP-2和MMP-3的表达。结果表明，T_3 （10^<-8>_M）可能在上调evt进入蜕膜的侵袭电位中起重要作用。

The present study was conducted to determine whether T_3 receptor exists in early placental extravillous trophoblasts (EVTs) and evaluate the influence of T_3 on Fas/Fas ligand expression, caspase-3, and poly (ADP-ribose) polymerase (PARP) cleavage and apoptosis in cultured early placental EVTs. Early placental EVTs expressed a 212-bp c-erb Aβ1 transcript and the T_3 receptor protein and exhibited significant levels of apoptosis in culture. Treatment with T_3 reduced the expression of Fas and Fas ligand as well as cleavage of caspase-3 and PARP and suppressed apoptosis in cultured EVTs. These results demonstrate that T_3 receptor is present in early placental EVTs and that T_3 suppresses apoptosis by down-regulating the expression of Fas and Fas ligand. Furthermore, in order to investigate the possible role of T_3 in the regulation of EVT invasion to the decidua, we have examined whether T_3 affects EVT invasive potential and the expression of matrix metalloproteinase-2 (MMP-2), MMP-3, tissue inhibitor metalloproteinase-1, fetal fibronectin (FN), and integrin α_5β_1 in cultured early placental EVTs. Matrigel invasion assay demonstrated that the treatment with T_3 significantly increased the number of cell projections of cultured EVTs. RT-PCR analysis revealed that the treatment with T_3 increased the expression of MMP-2, MMP-3, fetal FN, and integrin α_5β_1 mRNA in cultured EVTs. Immunocytochemical and Western immunoblot analysis revealed that treatment with T_3 increased the expression of MMP-2 and MMP-3 in cultured EVTs. The present results suggest that T_3 (10^<-8>_M) may play a vital role in up-regulating the invasive potential of EVTs into the decidua.