The MMP system in human ovulation: localization, regulation, and function

描述（由申请人提供）：在许多物种中，排卵前LH峰刺激卵泡破裂前卵巢基质金属蛋白酶（MMP）及其相关抑制剂TIMP（统称为MMP系统）增加。MMP系统在排卵中的重要作用来自于许多实验，其中卵母细胞释放被MMP抑制剂阻断。然而，除了我们的初步数据，没有什么是已知的进展和时间模式的基质金属蛋白酶和金属蛋白酶组织抑制剂参与排卵过程中的人。这个问题将在第一个特定目标中通过使用一个独特的模型来解决，其中将在hCG之前和之后的三个指定时间（早期、晚期和排卵后）收集人排卵期卵泡的颗粒、卵泡膜和基质。与人类卵泡破裂相关的MMP和TIMP家族的关键成员的表达模式将被阐明。具体目标#2将建立在这些观察结果的基础上，并在啮齿动物和人类中使用充分表征的模型，通过已知的LH刺激信号通路探索这些MMP和TIMP的调节。然而，一个关键的问题仍然是什么MMPs和TIMPs实际上在卵泡破裂的过程中做什么？我们认为，卵巢MMP系统指导排卵所必需的蛋白水解或“降解组”的变化。因此，特定目标#3将通过蛋白质组学分析阐明MMP作用的特定蛋白质靶点，从而使我们能够表征MMP和TIMP在排卵过程中的功能。该提案的一个主要优势是我们对MMP系统的广泛专业知识，该系统允许采用综合方法来了解MMP系统对卵泡破裂的细胞表达，调节和影响。这项研究的一个新的方面是使用良好的特征人类排卵前卵泡作为基础，探索MMP系统在人类排卵过程中的作用，这是从来没有完成。因此，提出的研究是非常及时的，以阐明这个精致的蛋白水解系统在卵泡破裂和卵母细胞释放的协调过程中发挥的作用，这是正常人类卵巢生理学的关键方面。公共卫生相关性：拟议的研究将调查人类排卵的潜在机制，这是一个卵子从卵巢卵泡释放的过程。这些研究将集中在一个蛋白水解酶家族，称为金属蛋白酶，我们认为它可以破坏卵泡壁，使卵子被释放。只有充分了解卵巢功能的这些基本原理，我们才能够促进或抑制排卵过程中与金属蛋白酶作用相关的事件，从而促进和增加生育力或以避孕方式降低生育力。

DESCRIPTION (provided by applicant): The preovulatory LH surge stimulates an increase in ovarian matrix metalloproteinases (MMPs) and their associated inhibitors, the TIMPs, (collectively referred to as the MMP system) prior to follicular rupture in many species. The paramount role of the MMP system in ovulation is forthcoming from numerous experiments where oocyte release is blocked by MMP inhibitors. Yet other than our preliminary data, nothing is known as to progression and temporal patterns of the MMPs and TIMPs involved in the ovulatory process in the human. This question will be addressed in the first Specific Aim by using a unique model where the granulosa, theca, and stroma from human periovulatory follicles will be collected prior to and at three designated times after hCG (early, late and postovulatory). The expression patterns of key members of the MMP and TIMP family associated with follicular rupture in the human will be illuminated. Specific Aim #2 will build upon these observational findings and explore the regulation of these MMPs and TIMPs by known LH stimulated signaling pathways using well characterized models in the rodent and human. However, one of the key questions remains as to what are the MMPs and TIMPs actually doing during the process of follicular rupture? We propose that the ovarian MMP system directs the requisite proteolytic or "degradomic" changes necessary for ovulation. Thus, Specific Aim #3 will elucidate specific protein targets of MMP action by proteomic profiling allowing us to characterize the function of the MMPs and TIMPs in the ovulatory process. A major strength of this proposal is our extensive expertise with the MMP system that allows an integrated approach to understand the cellular expression, regulation, and impact of the MMP system on follicular rupture. One novel aspect of this study is the use of well characterized human preovulatory follicles as a foundation to explore the role of the MMP system in the process of human ovulation, which has never been accomplished. As such the proposed studies are extremely timely to elucidate the role that this exquisite proteolytic system plays in the coordinated processes of follicular rupture and oocyte release which are key aspects of normal human ovarian physiology. PUBLIC HEALTH RELEVANCE: The proposed studies will investigate the underlying mechanism involved in human ovulation, which is a process where the egg is released from the follicle in the ovary. These studies will focus on a family of proteolytic enzymes, known as metalloproteinases, that we believe breakdown the wall of the ovarian follicle to allow the egg to be released. Only by fully understanding such basic tenets of ovarian function will we be able to promote or inhibit the events associated with metalloproteinase action during the ovulatory process thereby facilitating and increasing fertility or acting in a contraceptive manner to decrease fertility.