ENDOTHELIAL ACTIVATION BY CYTOKINES AND FATTY ACID

先兆子痫是一种浆液性产科综合征， 高血压，蛋白尿和全身水肿，影响约 7%的孕妇。 尽管它的承认， 古代，目前对这种疾病的治疗不是基于 了解其病理生理学，但仍然是经验性的： 胎儿和胎盘的分娩。 孕产妇和新生儿死亡率高 与先兆子痫相关的发病率和死亡率 医源性早产中断受影响的妊娠。 的 这种综合症背后的细胞生物学仍然是个谜。 申请项目0002中提出的研究扩展了我们的 正在进行的母体血管内皮功能障碍的研究 在先兆子痫，但与具体的重点，了解 脂肪酸和前列腺素异常的生化途径 新陈代谢. 15年多来，人们认识到， 母体和胎儿组织中前列腺素的产生是异常的 患有先兆子痫 拟议的研究将涉及 可能的机制，内皮细胞活化在这种综合征。 两 细胞因子TNF-α和内皮素-1已经被Dr. 先兆子痫妇女血浆中的Conrad（项目0005）和Taylor Fisher和McLaughlin博士（项目0003和0004）使用 胎盘缺氧的体外模型。 在具体目标#1中，我们将 研究这些细胞因子激活关键细胞因子的能力， 调节酶（磷脂酶A2和环氧化酶-2）参与 在内皮细胞前列腺素的生产。 感应， 修改（即，磷酸化）和这些酶的活性 将在人脐和蜕膜内皮细胞中进行评估。 调节脂肪酸结合和递送到内皮细胞中 在具体目标#2中阐述了白蛋白亚型的作用。 毒性 预防活性（TxPA），血浆白蛋白的pI-5.6亚型，将 纯化以研究其脂质结合及其调节 细胞内脂肪酸前体的可用性 前列腺素生成。 在具体目标#3中， 过氧化物酶体增殖物激活受体（PPARs）， 细胞内脂肪酸代谢物将被解决。 内皮 细胞PPARs将被鉴定并转染重组过氧化物酶体 增殖物应答元件（PPRE）报告基因构建体将被 用于筛选这些核受体的前列腺素类激活剂。 拟议的研究将描述以下途径： 细胞因子和脂肪酸激活内皮细胞， 先兆子痫 这些分子应该提供理想的目标， 治疗性拮抗剂的未来发展， 导致合理的治疗和可能的预防 先兆子痫

Preeclampsia is a serous obstetrical syndrome characterized by hypertension, proteinuria and generalized edema, that affects about 7 percent of pregnant women. Despite its recognition since antiquity, the current treatment of this disorder is not based on an understanding of its pathophysiology but remains empirical: delivery of the fetus and placenta. The high maternal and neonatal morbidity and mortality associated with preeclampsia results from the iatrogenic preterm interruption of affected pregnancies. The cellular biology that underlies this syndrome remains a mystery. The studies proposed in Project 0002 of the application extend our ongoing investigation of maternal vascular endothelial dysfunction in preeclampsia, but with the specific focus of understanding the biochemical pathways involved in abnormal fatty acid and prostanoid metabolism. For more than 15 years it has been recognized that prostaglandin production is abnormal in maternal and fetal tissues affected by preeclampsia. The proposed studies will address possible mechanisms of endothelial activation in this syndrome. Two cytokines, TNF-alpha and endothelin-1, have been identified by Drs. Conrad (Project 0005) and Taylor in the plasma of preeclamptic women and by Drs. Fisher and McLaughlin (Projects 0003 and 0004) using in vitro models of placental hypoxia. In Specific Aim #1, we will investigate the abilities of these cytokines to activate key regulatory enzymes (phospholipases A2 and cycloozygenase-2) involved in endothelial cell prostaglandin production. The induction, modification (i.e., phosphorylation) and activity of these enzymes will be assessed in human umbilical and decidual endothelial cells. Regulation of fatty acid binding and delivery into endothelial cells by albumin isoforms is addressed in specific Aim #2. Toxicity preventing activity (TxPA), a pI-5.6 isoform of plasma albumin, will be purified to study its lipid binding and its ability to modulate the availability of intracellular fatty acid precursors of prostanoid production. In Specific Aim #3 the activation of peroxisome proliferator activated receptors (PPARs) by extra- or intracellular fatty acid metabolites will be addressed. Endothelial cell PPARs will be identified and transfected recombinant peroxisome proliferator response element (PPRE) reporter constructs will be used to screen for prostanoid activators of these nuclear receptors. The proposed studies will characterize the pathways by which cytokines and fatty acids activate endothelial cells in preeclampsia. These molecules should provide ideal targets for the future development of therapeutic antagonists which ultimately could lead to the rational treatment and possible prophylaxis of preeclampsia.