MEMBRANE PRs AS NOVEL MEDIATORS OF PROGESTERONE-INDUCED NEUROPROTECTION

许多基础科学，流行病学和临床研究之间的差异，支持 激素治疗在预防与年龄相关的认知功能障碍方面的潜在益处，以及最近 妇女健康倡议记忆研究（WHIMS）的结果强调了一个事实，即我们的 对激素神经生物学的理解是不完整的。由于性腺类固醇激素的作用机制 在生殖组织中可能与大脑不同，更好地了解这些组织是如何形成的， 激素在大脑中的作用是必要的。为此，我们将有系统地探讨新成员的作用， 发现膜孕酮受体（mPR）介导的神经保护作用， 孕酮此外，我们认为WHIMS未能显示激素治疗的积极作用， 部分原因是激素治疗方案中使用的合成孕酮， 醋酸（MPA），并假设其缺乏疗效是由于其机制的重要差异， 相对于孕酮的作用。我们的假设将在原代皮层培养（外植体）中进行检验 和分离的神经元），其中我们已经证实了经典孕酮受体的表达 (PR)mPR也是。我们将使用补充药理学（细胞膜不可渗透 孕激素）、分子（siRNA）和遗传工具（PRKO小鼠）来实现以下目标： 如果mPR介导孕酮对ERK/MAPK通路的影响，那么马斯帕明（马斯帕明是一种我们认为 目的2：确定ERK的PR特异性模式是否 磷酸化可以解释孕酮和MPA的保护能力之间的差异;目的3： 确定mPR是否介导孕酮对细胞存活的影响;以及 孕酮在中风的体内模型中，特别是在经典的 PR已中断（PRKO）。卵巢切除的“中风”小鼠将作为一个共同的模型使用 本研究计划内的所有项目，并将加强和促进概念和 实验项目之间的整合。总的来说，本项目中提出的研究可以确定 mPR作为一种重要的分子，未来的药物发现工作可以靶向治疗或 预防由年龄或年龄相关疾病如阿尔茨海默病引起的脑功能障碍。

The discrepancy between numerous basic science, epidemiological and clinical studies that supported the potential benefit of hormone therapy in preventing age-associated cognitive impairment, and the recently published results from the Women's Health Initiative Memory Study (WHIMS), underscores the fact that our understanding of hormone neurobiology is incomplete. Since the mechanisms of gonadal steroid hormones in reproductive tissue may not be identical to that of the brain, a better understanding of how these hormones work in the brain is needed. To this end, we will systematically address the role of the newly discovered membrane progesterone receptor (mPR) in mediating the neuroprotective effects of progesterone. Further, we propose that the failure of the WHIMS to show positive effects of hormone therapy was due, in part, to the synthetic progestin used in the hormone therapy regimen, medroxyprogesterone acetate (MPA), and hypothesize that its lack of efficacy is due to important differences in its mechanism of action, relative to that of progesterone. Our hypotheses will be tested in primary cortical cultures (explants and dissociated neurons) in which we have confirmed the expression of the classical progesterone receptor (PR) and the mPR as well. We will use complementary pharmacological (cell membrane impermeable progestins), molecular (siRNA) and genetic tools (PRKO mice) to address the following aims: Aim 1: deterimine if the mPR mediates the effects of progesterone on the ERK/MAPK pathway (a pathway that we show is required for progesterone-induced protection); Aim 2: determine if PR-specific patterns of ERK phosphorylation may explain the difference between progesterone's and MPA's ability to protect; Aim 3: determine if the mPR mediates the effect of progesterone on cell survival; and Aim 4: determine if progesterone protects in an in vivo model of stroke, specifically, in animals whose expression of the classical PR has been disrupted (PRKO). The ovariectomized, "stroked" mouse will serve as a common model used by all projects within this Program of research and will enhance and facilitate the conceptual and experimental integration among projects. Collectively, the studies proposed in this project may identify the mPR as an important molecule to which future drug discovery efforts can target for the treatment or prevention of brain dysfunction resulting from age- or age-associated diseases like Alzheimer's Disease.