Function of the Decidual Tissue

描述（由申请人提供）：怀孕的建立和维持需要一个特殊的母体组织，蜕膜的协调活动。我们和其他实验室的广泛研究已经确定，蜕膜细胞能够产生激素和细胞因子，并表达类固醇生成酶。我们研究的总体目标是了解这些蜕膜衍生因素在维持胎儿发育的适当环境中的作用。基因敲除策略揭示了泌乳素（PRL）、白介素-11 （IL-11）以及个体类固醇生成酶5 α -还原酶1型（5alphaR1）和20 α -羟基类固醇脱氢酶（20alphaHSD）在啮齿动物正常妊娠过程中的重要作用。这项拨款申请的重点是确定这些蜕膜衍生因素的作用、调节和相互作用。第一个具体目标集中在蜕膜prl在抑制IL-6和caspase-3中的作用，这两个基因分别与炎症和细胞死亡有关。利用PRL和IL-6敲除以及原代蜕细胞和细胞系，我们拟检验是否确实是IL-6的表达导致了PRL（-/-）小鼠的胎儿死亡，是否可以通过产生PRL和IL-6的双敲除小鼠来挽救妊娠，以及在PRL缺失小鼠中阻止IL-6的产生。我们还将确定PRL沉默IL-6基因个体表达的分子机制。这一特定目标的另一个目标是基于我们的发现，即dPRL作为一种生存因子，可阻止蜕膜中细胞死亡诱导剂caspase-3的表达和激活。我们将研究dPRL阻止该刽子手caspase活性的机制，并确定PRL对caspase 3的抑制是否在转录水平上，是否涉及Akt/forkhead通路。第二个目标将关注蜕膜IL-11在妊娠正常进程中的作用，更具体地说，是il - 11rα基因缺失导致蜕膜小和滋养细胞侵袭失控的原因。最后，在第三个目标中，我们将研究个体类固醇生成酶在维持妊娠中的调节和作用。我们将研究PRL阻止个体20alphaHSD表达的机制，以及PGF2a是否在妊娠末期刺激其表达。我们还将研究5alphaR1是否在IL-11Ralpha缺失的小鼠中不表达，从而导致高水平的循环雌二醇并加速胎儿死亡。我们还将验证5alphaReductase 1型缺失小鼠的胎儿死亡是由于高水平雌二醇抑制蜕膜中IL-11信号传导的假设。

DESCRIPTION (provided by applicant): The establishment and maintenance of pregnancy requires the coordinate activity of a specialized maternal tissue, the decidua. Extensive investigation from our and other laboratories has established that decidual cells are able to produce hormones and cytokines, and to express steroidogenic enzymes. The overall objective of our research is to understand the involvement of these decidua-derived factors in the maintenance of the proper milieu for fetal development. Gene knockout strategies have revealed a crucial role for prolactin (PRL), Interleukin-11 (IL-11) and for decidual steroidogenic enzymes, 5alpha-reductase type 1 (5alphaR1) and 20a-hydroxysteroid dehydrogenase (20alphaHSD), in the normal progress of pregnancy in rodents. The focus of this grant application is to define the role, regulation and interaction of these decidua-derived factors. The first specific aim centers on the role of decidual-PRL in the inhibition of IL-6 and caspase-3, genes involved in inflammation and cell death respectively. Using both PRL and IL-6 knockouts as well as primary decidual cells and cell lines, we propose to examine whether it is indeed IL-6 expression that leads to fetal death in the PRL (-/-) mice, whether pregnancy can be salvaged by generating double knockout mice for PRL and IL-6, and by preventing IL-6 production in the PRL null mice. We will also determine the molecular mechanism by which PRL silences the decidual expression of the IL-6 gene. Another objective of this specific aim is based on our findings that dPRL acts as a survival factor preventing the expression and activation of the cell death inducer, caspase-3, in the decidua. We will examine the mechanism by which dPRL prevents the activity of this executioner caspase, and determine whether PRL inhibition of caspase 3 is at the transcriptional level and involves the Akt/forkhead pathway. The second aim will focus on the role of decidual IL-11 in the normal progress of pregnancy and more specifically on the reason why IL-11Ralpha gene deletion leads to small decidua and to uncontrolled trophoblast invasion. Finally, in the third aim, we will examine the regulation and the role of decidual steroidogenic enzymes in the maintenance of pregnancy. We will examine the mechanism by which PRL prevents decidual 20alphaHSD expression and whether PGF2a stimulates its expression at the end of pregnancy. We will also examine whether 5alphaR1 is not expressed in the IL-11Ralpha null mice causing high levels of circulating estradiol and precipitating fetal death. We will also test the hypothesis that fetal death in 5alphaReductase type 1 null mice is due to the inhibition of IL-11 signaling in the decidua by high levels of estradiol.