INSULIN AND IGF-1 SIGNALING IN OVARIAN CELLS

描述(根据申请者的描述改编)：我们的初步研究 来自胰岛素受体基因敲除的转基因小鼠的卵巢 底物-1基因(IRS-1KO)显示卵母细胞在黄体组织中被包裹 排卵的动物数量大约是野生动物的三分之一- 型(WT)对照组。IRS-1KO卵巢也表现出一种罕见的表型， 多卵泡(双卵母细胞)卵泡。这些发现暗示了 胰岛素信号转导受损与卵巢功能的表型变化 之前没有被承认过。因此，总体研究目标是 是验证和扩展这些发现，以确定胰岛素的作用 体内卵巢水平的信号通路组件。有了这个 背景，关于这些效应器如何帮助执行胰岛素的详细研究- 和卵泡刺激素-FSH)调节的细胞终点选择 存活、凋亡或有丝分裂将在扩大的应用中进行。这个 WT和IRS-1 KO小鼠卵巢的多方面比较 具体目标如下：1)评估卵母细胞数和生化标志物 新生动物对外源性促性腺激素的排卵反应 青春期前动物，以及2)评估早期的水平和/或活动 胰岛素信号通路中的效应物(IRS-1、IRS-2、P13-K、Akt) 促性腺激素调节的滤泡细胞有丝分裂和凋亡。具体目标3 将把体内研究扩展到对培养猪的体外分析 颗粒细胞(PGC)：A)检查FSH之间可能的联系 受体和胰岛素/胰岛素样生长因子-1受体信号通路，以及b)发展 一种检测BAD(Bcl-2相关死亡促进因子)的改进方法 细胞命运的调节者，可被Akt磷酸化。结果是 获得的基本信息也可能有助于更完整的 对一个重要的临床实体--多囊卵巢综合征的认识 (PCOS)，部分表现为加速的卵泡闭锁 (细胞凋亡)、胰岛素抵抗和阳萎。

DESCRIPTION (Adapted from applicant's description): Our preliminary studies of ovaries from transgenic mice with a knockout of the insulin receptor substrate-1 gene (IRS-1 KO) showed entrapment of the oocyte in luteal tissue and that the number of animals ovulating was about one-third that of the wild- type (WT) control group. The IRS-1 KO ovaries also exhibited a rare phenotype, polyovular (bi-oocyte) follicles. These findings imply a relationship between compromised insulin signaling and phenotypic change in ovarian function which have not been previously recognized. Accordingly, the overall study objective is to validate and extend these findings to establish the role of insulin signaling pathway components at the ovarian level in vivo. With this background, detailed studies of how these effectors help execute the insulin- and Follicle-stimulating hormone-FSH) regulated end point alternatives of cell survival, apoptosis, or mitosis will proceed in an expanded application. The ovaries of WT and IRS-1 KO mice will be compared in various aspects in the following specific aims: 1) to evaluate oocyte numbers and biochemical markers in neonatal animals and the ovulatory response to exogenous gonadotropins in prepubertal animals, and 2) to assess levels and/or activity of early effectors in the insulin signaling pathway (IRS-1, IRS-2, P13-K, Akt) during gonadotropin-regulated follicular cell mitosis and apoptosis. Specific Aim 3 will extend the in vivo studies to in vitro analysis in cultured porcine granulosa cells (pGCs) to: a) examine possible connections between the FSH receptor and insulin/IGF-1 receptor signaling pathways, and b) develop improved methods to detect BAD (Bcl-2-associated death promoter), a critical regulator of cell fate which can be phosphorylated by Akt. The results obtained may also contribute information basic to a more complete understanding of an important clinical entity, polycystic ovarian syndrome (PCOS), which is characterized in part by accelerated follicle atresia (apoptosis), insulin resistance, and virilism.