PLACENTAL/UTERINE EFFECTS OF CHLORINATED HYDROCARBONS

拟议的研究将调查机制， 氯化碳氢化合物2，3，7，8-四氯二苯并对二恶英（TCDD）和 多氯联苯（PCBs）对胎盘有破坏性影响， 子宫功能 假设是TCDD和PCB改变了胎盘- 子宫旁分泌和自分泌网络， 滋养层细胞的侵袭、增殖和激素分泌，以及 子宫细胞的生长。 主要网络涉及表皮生长 EGF及其受体（EGF-R），转化生长因子 （TGF）-α和-β、细胞因子白细胞介素（IL）-1B和TGF-β 蛋白酶抑制剂、纤溶酶原激活物抑制剂（派）。 所述PCB 同系物3，3 '，4，4'-四氯和2，2 '，4，4'，5，5 '-六氯，以及 混合物Arochlor 1254将被研究，以代表不同水平的 AHH诱导活性。 特定目的#1：暴露于培养的人胎盘滋养层细胞 细胞系对TCDD和PCBs的反应改变了基因的表达， 胎盘生长和内分泌功能 实验将具体 评估：a）绒毛膜癌中EGF受体结合和激酶活性 JEG-3和BeWo细胞系，以确定是否存在下调 具有改变的细胞增殖或激素分泌的受体; B） 在其他人类细胞系中被识别为受TCDD调节的基因， 包括TGF-α、TGF-β、IL-1B和派; 细胞色素P-450 1A 1和PCB代谢，以确定是否存在剂量- 与EGF受体和/或生长变化平行的相关效应 通过Ah受体表达因子。 具体目标#2：暴露于培养的人子宫内膜 腺癌细胞对PCBs和TCDD的表达改变生长 调控基因？ 实验将评估：a）EGF-R结合和激酶 活性和EGF刺激的细胞增殖; B）雌激素受体 水平，以确定细胞对雌激素的反应是否 c）TGF-α、TGF-β、IL-1B和派的表达; d） 诱导细胞色素P450 1A 1和PCB代谢的剂量反应 与上述a）、B）和c）的关系。 具体目标#3：在妊娠大鼠中， 相应的PCB改变P450 1A 1、TGF-β的胎盘基因表达。 α和β、IL-1B和派与胎儿-胎盘生长的相关性 弱智？ 实验将评价：a）晚期妊娠中的胎儿-胎盘生长 B）TGF-α h、TGF-β、IL-1 B和派在妊娠中的表达。 胎盘和蜕膜; c）细胞色素P450 1A 1诱导和PCB代谢 对于上述a）和B）的剂量反应关系。 特定目的#4：胎盘氨基酸转运系统的表达 与妊娠期胎儿-胎盘生长迟缓相关 用多氯联苯和四氯二苯并对二恶英处理的大鼠 a）通过系统的氨基酸转运 将在分离的囊泡制备物中检查B、+、y+、XAG-和A， 微绒毛和基底膜; B）检测mRNA水平 利用系统y+和XAG-的cDNA探针; c）细胞色素P450 1A 1 上述a）和B）的剂量-反应关系的诱导。

The proposed research will investigate mechanisms by which the chlorinated hydrocarbons 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) have disruptive effects on placental- uterine function. The hypothesis is that TCDD and PCBs alter placental- uterine paracrine and autocrine networks which are important for trophoblast invasiveness, proliferation and hormone secretion, as well as uterine cell growth. The major networks involve epidermal growth factor (EGF) and its receptor (EGF-R), transforming growth factors (TGFs)-alpha and -betas, the cytokine interleukin (IL) -1B and the protease inhibitor, plasminogen activator inhibitor (PAI). The PCB congeners 3,3',4,4'-tetrachloro and 2,2',4,4',5,5'-hexachloro, and the mixture Arochlor 1254 will be studied to represent different levels of AHH induction activity. SPECIFIC AIM #1: Does exposure of cultured human placental trophoblstic cell lines to TCDD and PCBs alter expression of genes important for placental growth and endocrine function? Experiments will specifically evaluate: a) EGF receptor binding and kinase activity in choriocarcinoma JEG-3 and BeWo cell lines to determine whether there is down-regulation of receptors with altered cell proliferation or hormone secretion; b) The genes recognized to be regulated by TCDD in other human cell lines, including TGF-alpha, TGF-betas, IL-1B, and PAI; c) Induction of cytochrome P-450 1A1 and PCB metabolism to determine if there are dose- related effects in parallel with changes in EGF receptors and/or growth factor expression through the Ah receptor. SPECIFIC AIM #2: Does exposure of cultured human endometrial adenocarcinoma cells to PCBs and TCDD alter expression of growth regulatory genes? Experiments will evaluate: a) EGF-R binding and kinase activity and EGF-stimulated cell proliferation; b) Estrogen receptor levels to determine whether the cellular response to estrogens is altered; c) Expression of TGF-alpha, TGF-betas, IL-1B, and PAI; d) Induction of cytochrome P450 1A1 and PCB metabolism for dose-response relationships with a), b) and c) above. SPECIFIC AIM #3: In pregnant rats, does administration of TCDD and the respective PCBs alter expression of placental genes for P450 1A1,TGFs- alpha and -beta, IL-1B and PAI in correlation with feto-placental growth retardation? Experiments will evaluate: a) Feto-placental growth in late gestation; b) Expression of TGF-alpah, TGF-betas, IL-1B, and PAI in placenta and decidua; c) Cytochrome P450 1A1 induction and PCB metabolism for dose response relationships with a) and b) above. SPECIFIC AIM #4: Is expression of placental amino acid transport systems altered in correlation with feto-placental growth retardation in pregnant rats treated with PCBs and TCDD? a) Amino acid transport via Systems B,+,y+,XAG-, and A will be examined in isolated vesicle preparations from the microvillous and basal membranes; b) mRNA levels will be examined utilizing cDNA probes to Systems y+ and XAG-; c) Cytochrome P450 1A1 induction for dos-response relationships with a) and b) above.