Effects of Phthalates on Trophoblast Differentiation: From Biology to Biomarkers

描述（由申请人提供）：候选人寻求资金，以扩大她在流行病学的培训在两个新的方向，即人类胎盘生物学和质谱。学习这些基于实验室的方法将使她更接近于实现她的长期目标，成为一名独立的学术研究者，并为研究低剂量慢性暴露于内分泌干扰化合物及其在妊娠早期健康障碍中的作用提供新的见解和方法。在K99阶段，在Susan Fisher博士的主要指导下，候选人将接受滋养层（Tb）干细胞生物学的培训，最先进的基于微阵列的方法用于在全球范围内分析基因表达，包括用于数据分析的生物信息学方法。在她最初的博士后研究结果的基础上，这位候选人提出理论，认为Tbs是执行胎盘许多最重要功能的特化细胞，在怀孕早期暴露于邻苯二甲酸酯，对胎盘发育和功能产生不利影响。 研究者将检验关于临床结局和生物学参数的假设，包括人类胎盘发育和功能的分子、细胞和形态学指标。 具体来说，他们将进行实验，以测试培养的人类Tb干细胞在暴露于环境相关剂量的邻苯二甲酸二（2-乙基己基）酯和邻苯二甲酸二正丁酯（Aim 1）时，基因表达模式将显示出剂量依赖性变化的假设。 在R 00阶段，候选人将在妊娠女性的纵向研究中检验理论，即体外邻苯二甲酸酯暴露导致差异表达的胎盘基因在体内以剂量依赖性方式受到类似调节（目标2）。作为该目标的一部分，候选人将评价产前暴露的常规剂量计、尿邻苯二甲酸酯代谢物浓度和靶胎盘组织剂量之间的相关性。在产科/妇科，质谱，生物统计学和流行病学的主要导师和共同导师将指导候选人学习完成本提案中规定的目标所需的方法的过程。在该培训计划结束时，候选人将开发出新的方法和工具，她和其他研究者可以使用这些方法和工具就妊娠期间邻苯二甲酸酯暴露对胎盘功能的改变以及随后的人类发育的影响提出更直接的问题。这项工作很重要，因为邻苯二甲酸酯可以破坏细胞和组织分化，是啮齿动物中公认的生殖和发育毒物;但这些发现与人类的相关性尚不清楚。利用邻苯二甲酸酯诱导的胎盘损伤的特异性生物标志物，将有可能识别高风险妊娠，并在人群水平上提供预防机会，并可能在医疗保健提供系统水平上进行干预，以改善胎盘和胎儿结局。 公共卫生相关性：该项目的目标是准备博士詹妮弗Adibi过渡到一个位置作为一个独立的学术研究人员在环境健康科学专注于邻苯二甲酸酯暴露在人类怀孕期间的后果。她将使用体外和体内模型进行实验，以检验这种有毒物质破坏滋养层分化的假设，从而破坏胎盘发育和功能，从而损害人类在子宫内的发育。

DESCRIPTION (provided by applicant): The candidate seeks funding to extend her training in epidemiology in two new directions, namely, human placental biology and mass spectrometry. Learning these laboratory-based methods will move her closer to accomplishing her long-term goals of becoming an independent academic investigator and offering new insights and methods to research on low dose chronic exposures to endocrine disrupting compounds and their role in health disorders that originate in early pregnancy. During the K99 phase, under the primary mentorship of Dr. Susan Fisher, the candidate will receive training in trophoblast (Tb) stem cell biology, state-of-the-art microarray-based methodologies that are used to analyze gene expression at a global level, including bioinformatics approaches for data analysis. Building on the results of her initial postdoctoral research, the candidate theorize that Tbs, the specialized cells that carry out many of the placenta's most important functions, are exposed to phthalates early in pregnancy with adverse consequences on placental development and function. The investigators will test hypotheses regarding clinical outcomes and biological parameters that include molecular, cellular, and morphologic measures of human placental development and function. Specifically, they will conduct experiments to test the hypothesis that cultured human Tb stem cells will show dose-dependent changes in patterns of gene expression when they are exposed to environmentally relevant doses of di-(2-ethylhexyl) phthalate and di-n-butyl phthalate (Aim 1). During the R00 phase, the candidate will test the theory, in a longitudinal study of pregnant women, that placental genes that are differentially expressed as a consequence of phthalate exposure in vitro are similarly regulated, in a dose-dependent manner, in vivo (Aim 2). As part of this aim, the candidate will evaluate the correlation between the conventional dosimeter of prenatal exposure, urinary phthalate metabolite concentrations, and the dose to the target placental tissue. The primary mentor and co-mentors in obstetrics/gynecology, mass spectrometry, biostatistics, and epidemiology will guide the process whereby the candidate learn the methods that are required to accomplish the goals set forth in this proposal. At the conclusion of this training program the candidate will have developed new methodologies and tools that she and other investigators can use to ask more directed questions about the consequences of phthalate exposures during pregnancy in terms of alterations in placental function and consequently, human development. This work is important because phthalates, which can disrupt cell and tissue differentiation, are well established as reproductive and developmental toxicants in rodents; yet the relevance of these finding to humans is not well understood. With biomarkers specific to phthalate-induced placental damage, it will become possible to identify high-risk pregnancies and provide opportunities for prevention, at the population level, and possibly intervention at the level of health care delivery systems to improve placental and fetal outcomes. Public Health Relevance: The goal of this project is to prepare Dr. Jennifer Adibi to transition to a position as an independent academic investigator in environmental health sciences focusing on the consequences of phthalate exposures during human pregnancy. She will conduct experiments using in vitro and in vivo models to test the hypothesis that this toxicant disrupts trophoblast differentiation, and therefore placental development and function, thereby compromising human development in-utero.