17 alpha-Hydroxylase Expression in Human Ovarian Cells

拟议中的实验旨在阐明雄激素的调节机制。 正常周期妇女和多囊卵巢妇女卵巢膜内膜细胞的生物合成 综合征(PCOS)。在过去的资助期内，我们获得了令人振奋的数据，表明 PCOS卵泡膜细胞产生雄激素和增强P45017a-羟基酶基因表达 这是由于MEK1/ERK通路激活状态的降低和对 MKK3通路的激活状态。我们观察到正常卵泡膜细胞感染 表达显性阴性MEK1和成分活性MKK3的腺病毒重现PCOS囊膜 细胞表型。我们现在有了工具来充分探索 MAPK信号通路。在这项提案中，我们将检验卵巢雄激素增加的假设 多囊卵巢综合征囊膜中丝裂原活化蛋白激酶(MAPK)信号的改变是产物产生的结果 细胞。目的1研究目的是调查上游信号成分的调节失调(S) ERK和p38信号通路(S)(即Raf-1、MEKK1、MEKK3)的表达直接影响下游 CYP17和Cyp11a1基因在每条同源通路中的信号成分 在PCOS卵泡膜细胞中，雄激素的生物合成和表达上调。我们还将研究是否 一条通路中信号成分的失调导致信号的代偿性变化(S) 通过平行通道(S)。在目标2中，我们将调查ERK和p38的变化程度 信号转导促进多囊卵巢综合征细胞色素P17和Cyp11a1基因转录及mRNA稳定性 膜细胞。 在整个文献中，有数据支持肿瘤坏死因子a(TNF)抑制膜 细胞色素P17基因表达与雄激素的生物合成然而，这些数据与 观察多囊卵巢综合征患者外周血和卵泡液中肿瘤坏死因子水平升高。在《目标3》中， 我们将研究PCOS卵泡膜细胞中MAPK信号的缺陷对肿瘤坏死因子依赖性的影响程度 雄激素生物合成的调控。这些研究的结果将提供关于 卵巢雄激素产生增加的原因和分子基础，并导致新的 多囊卵巢综合征妇女的治疗目标。

The proposed experiments are designed to elucidate the regulatory mechanisms underlying androgen biosynthesis in theca interna cells from ovaries of normal cycling women and women with polycystic ovary syndrome (PCOS). During the past funding period, we obtained exciting data demonstrating that increased androgen production and augmented P450 17a-hydroxylase (CYP17) gene expression in PCOS theca cells results from a combined reduction in the activation state of the MEK1/ERK pathway and a stimulation in the activation state of the MKK3 pathway. We have observed that infection of normal theca cells with adenovirus expressing dominant negative MEK1 and constitutively active MKK3 recapitulates a PCOS theca cell phenotype. We now have the tools to fully explore the contributions of the other components of the MAPK signaling pathways. In this proposal we will test the hypothesis that increased ovarian androgen production is a consequence of altered mitogen activated protein kinase (MAPK) signaling in PCOS theca cells. Aim 1 studies are designed to investigate whether dysregulation of upstream signaling component(s) of the ERK and p38 signaling pathway(s) (i.e., Raf-1, MEKK1, MEKK3) directly affect the down stream signaling components of each homologous pathway to the extent that CYP17 and CYP11A1 gene expression, and androgen biosynthesis are up-regulated in PCOS theca cells. We will also examine whether dysregulation of signaling components from one pathway result(s) in compensatory changes in signaling through parallel pathway(s). In Aim 2 we will investigate the extent to which alterations in ERK and p38 signaling contribute to increased CYP17 and CYP11A1 gene transcription and mRNA stability in PCOS theca cells. Throughout the literature there are data to support that tumor necrosis factor a (TNF) inhibitsthecal CYP17 gene expression and androgen biosynthesis. However, these data are contradictory with the observation that PCOS women have elevated circulating plasma and follicular fluid levels of TNF. In Aim 3, we will examine the extent to which defects in MAPK signaling in PCOS theca cells affects TNF-dependent regulation of androgen biosynthesis. Results of these studies will provide both new insights regarding the cause and molecular basis for increased ovarian androgen production, and lead to the development of new targets for treatment of women with PCOS.