Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania, USA.
Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
Environ Health Perspect. 2017 Oct 31;125(10):107010. doi: 10.1289/EHP1539.
Observational studies have reported associations between maternal phthalate levels and adverse outcomes at birth and in the health of the child. Effects on placental function have been suggested as a biologic basis for these findings.
We evaluated the effects of phthalates on placental function by measuring relevant candidate genes and proteins.
Human trophoblast progenitor cells were isolated at 7-14 wk of pregnancy (two female and three male concepti), and villous cytotrophoblast cells (vCTBs) were isolated at 15-20 wk (three female and four male concepti). Cells were cultured with four phthalate metabolites and their combination at concentrations based on levels found previously in the urine of pregnant women: mono--butyl (MnBP, 200 nM), monobenzyl (MBzP, 3μM), mono-2-ethylhexyl (MEHP, 700 nM), and monoethyl (MEP, 1.5μM) phthalates. mRNA levels of , , , , , and the intracellular β subunit of human chorionic gonadotropin (hCGβ) and peroxisome proliferator activated receptor γ (PPARγ) were measured in the cellular extracts, and protein levels for four forms of secreted hCG were measured in the conditioned media.
Previously reported associations between maternal phthalates and placental gene expression were reproduced experimentally: MnBP with , MBzP with , and MEHP with . and hCGβ were up-regulated by MBzP. In some cases, there were marked, even opposite, differences in response by sex of the cells. There was evidence of agonism in female cells and antagonism in male cells of PPARγ by simultaneous exposure to multiple phthalates.
Concentrations of MnBP, MBzP and MEHP similar to those found in the urine of pregnant women consistently altered hCG and PPARγ expression in primary placental cells. These findings provide evidence for the molecular basis by which phthalates may alter placental function, and they provide a preliminary mechanistic hypothesis for opposite responses by sex. https://doi.org/10.1289/EHP1539.
观察性研究报告称，母体邻苯二甲酸酯水平与出生时和儿童健康的不良结局之间存在关联。这些发现的生物学基础被认为是对胎盘功能的影响。
我们通过测量相关候选基因和蛋白质来评估邻苯二甲酸酯对胎盘功能的影响。
在妊娠 7-14 周时分离人滋养层祖细胞（两个女性和三个男性胚胎），并在妊娠 15-20 周时分离绒毛滋养层细胞（vCTBs）（三个女性和四个男性胚胎）。细胞在浓度基于先前在孕妇尿液中发现的浓度下用四种邻苯二甲酸酯代谢物及其组合培养：单丁基邻苯二甲酸酯（MnBP，200nM）、单苄基邻苯二甲酸酯（MBzP，3μM）、单-2-乙基己基邻苯二甲酸酯（MEHP，700nM）和单乙基邻苯二甲酸酯（MEP，1.5μM）。测量细胞提取物中 、 、 、 、人绒毛膜促性腺激素β 亚基（hCGβ）和过氧化物酶体增殖物激活受体 γ（PPARγ）的 mRNA 水平，并测量条件培养基中四种形式分泌型 hCG 的蛋白水平。
实验重现了先前报道的母体邻苯二甲酸酯与胎盘基因表达之间的关联：MnBP 与 、MBzP 与 、MEHP 与 。MBzP 上调 和 hCGβ。在某些情况下，细胞性别之间存在明显的、甚至相反的反应差异。同时暴露于多种邻苯二甲酸酯时，女性细胞中的 PPARγ 表现出激动作用，而男性细胞中表现出拮抗作用。
与孕妇尿液中发现的浓度相似的 MnBP、MBzP 和 MEHP 浓度一致改变了原代胎盘细胞中 hCG 和 PPARγ 的表达。这些发现为邻苯二甲酸酯可能改变胎盘功能的分子基础提供了证据，并为性别相反的反应提供了初步的机制假设。https://doi.org/10.1289/EHP1539.
