PPAR Function in human pregnancy and preeclampsia

描述(申请人提供)：这项建议的目的是描述过氧化体增殖物激活受体(PPAR)在正常妊娠中的功能，以及在与妊娠综合征、先兆子痫(PE)相关的代谢紊乱中的功能。在美国，20%的产妇死亡是由PE造成的。PE突然发生在怀孕中后期或晚期，以高血压、蛋白尿和全身浮肿为特征。PE的病因仍然难以捉摸，唯一有效的治疗方法是立即分娩，导致早产并发症导致高水平的婴儿发病率和死亡率。因此，由于这种综合征，母亲和孩子都面临着严重的健康风险。本项目将评估PPAR在正常妊娠中对母体能量代谢的调节，以及它在PE中可能的变化。尽管它们不像经典的PE三联征(即高血压、蛋白尿和水肿)那样被广泛认识，但血脂异常、肥胖和糖耐量异常也是PE综合征的常见方面。PPAR在调节脂肪和葡萄糖代谢方面起着关键作用，我们已经证明，在正常妊娠过程中，循环中的PPAR激活物增加。在具体目标1中，我们建议使用质谱仪，作为我们现有的高效液相色谱分析的辅助手段，来鉴定妊娠血浆中存在的PPAR激活剂(S)。配体结合分析将确定所鉴定的化合物(S)是否是PPAR的直接高亲和力配体。我们还将确定哪些特定的PPAR被循环化合物结合并激活(S)。在特定的目标2中，我们选择了两个在胎盘生长和功能中起关键作用的候选基因(人胎盘催乳素[HPL]和血管内皮生长因子[VEGF])。我们的初步研究表明，PPAR可以调节这两个基因，并且这两个基因产物在PE中的表达都发生了变化。使用PPARg的特定抑制剂，可以量化全部或部分由于PPARg活性而导致的HPL和VEGF表达和分泌的差异。在具体目标3中，将检测正常妊娠和PE妊娠中已知的改变体内PPAR功能的PPAR多态的频率。对编码每个特定基因突变的区域进行PCR扩增后，将进行诊断限制性内切酶消化，以便对正常妊娠和PE妊娠的母亲和婴儿进行基因分型。这些基因的单核苷酸多态也将被寻找。我们期望我们多方面的方法来阐明PPAR在正常妊娠和PE中的作用，将为PE及其临床并发症的潜在病理生理学和最终治疗提供新的线索。

DESCRIPTION (provided by applicant): The objective of this proposal is to characterize the function of Peroxisome Proliferator-Activated Receptors (PPARs) in normal human pregnancy, and in the metabolic disturbances associated with the pregnancy syndrome, preeclampsia (PE). PE is responsible for 20% of maternal deaths in the U.S. PE occurs suddenly in the late second or third trimester of pregnancy and is characterized by high blood pressure, proteinuria, and generalized edema. The cause of PE remains elusive, and the only effective treatment is immediate delivery of the baby, resulting in high levels of infant morbidity and mortality due to complications of premature birth. Thus, both mother and child suffer serious health risks due to this syndrome. This project will evaluate PPAR regulation of maternal energy metabolism in normal pregnancy, and its possible alteration in PE. Although they are not as widely recognized as the classical triad of PE signs (i.e., hypertension, proteinuria and edema), dyslipidemia, obesity and aberrant glucose tolerance also are common facets of the PE syndrome. PPARs play critical roles in the regulation of lipid and glucose metabolism, and we have demonstrated that circulating PPAR activators increase during the course of normal pregnancy. In Specific Aim 1, we propose to use mass spectrometry, as an adjunct to our existing analyses by HPLC, to identify the PPAR activator(s) present in pregnancy plasma. Ligand binding assays will determine whether the identified compound(s) is a direct high affinity ligand of PPARs. We also will determine which specific PPARs are bound and activated by the circulating compound(s). In Specific Aim 2, we have selected two candidate genes (human placental lactogen [hPL] and vascular endothelial growth factor [VEGF]) that play key roles in placental growth and function. Our preliminary studies indicate that PPARs can regulate both genes and that the expression of both gene products is altered in PE. Using a specific inhibitor of PPARg, differences in expression and secretion of hPL and VEGF, due in whole or in part to PPARg activity, will be quantified. In Specific Aim 3, the frequency of PPAR polymorphisms known to alter PPAR function in vivo will be examined in both normal and PE pregnancy. PCR amplification of regions encoding each specific genetic mutation will be followed by diagnostic restriction enzyme digestion in order to genotype both mothers and babies of normal and PE pregnancies. Single nucleotide polymorphisms in these genes also will be sought. We anticipate that our multi-faceted approach to elucidate the role of PPAR action in normal pregnancy and PE will provide new clues to the underlying pathophysiology, and ultimately, therapy of PE and its clinical complications.