The Aging Pituitary-Gonadal Axis

衰老的垂体-性腺轴

• 批准号: 7802094
• 负责人: GEORGE R BOUSFIELD
• 金额: $ 125.91万
• 依托单位: WICHITA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-15 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7802094
• 关键词: Aging; Pituitary; Gonadal; Axis

DESCRIPTION (provided by applicant): Five years of support are requested to study the aging pituitary ovarian axis. We seek to understand pituitary-ovarian communication via follicle-stimulating hormone (FSH). It is well known that in women over the age of 35 fertility declines compared with younger women. Infertility clinics report decreased responsiveness of older women to exogenous FSH preparations. This project will focus on the response of the aging ovary to a change in relative abundance of two major human (h) FSH glycoforms. The classic hFSH possessing both alpha subunit and beta subunit oligosaccharides is designated tetra-glycosylated hFSH and a novel hFSH glycoform possessing only alpha subunit oligosaccharides is designated di-glycosylated hFSH. Women aged 21-24 express more di-glycosylated hFSH than tetra-glycosylated hFSH, perimenopausal women express slightly less di-glycosylated hFSH, while post-menopausal women express primarily tetra-glycosylated hFSH. Project 1 will investigate the changes in relative abundance of hFSH glycoforms during the menstrual cycle that are associated with increasing age and study mechanisms for glycan modulation of FSH receptor binding and activation. Project 2 will compare the activities of hFSH glycoforms in a variety of signal transduction assays in the ovary in order to identify possible mechanisms that enhance the biological activity of di-glycosylated hFSH. The differential effects of both glycoforms on bone resorption will also be studied. Project 3 will create mouse models to test the hypothesis that both hFSH glycoforms are necessary for reproductive function. A double hFSH¿ glycosylation mutant will replace the normal mFSH¿ gene. This line will be crossed with FSH¿ null mice to see if it can rescue female infertility. Purified hFSH glycoforms will also be tested in vivo using FSH null mice. The WSU FSH process core laboratory (Core B) will provide well characterized purified hFSH glycoforms, to all projects. The initial products will be di-glycosylated hFSH and tetra-glycosylated hFSH, which are of interest to all the scientific projects, but are not available from other sources. Recombinant di-glycosylated hFSH will be expressed first, due to low abundance in natural sources. Core B will characterize glycan populatlons at each occupied N-glycosylation site, thereby providing fully characterized glycoforms with known, rather than assumed glycosylation differences. Core B will also provide cell culture and assay services to project investigators. The WSU bioinformatics core (Core C) will provide a data-sharing platform readily accessible to all investigators via the internet. The outcome of this research will be a better understanding of the mechanisms for reduced ovarian responsiveness with aging that may lead to the development of more effective FSH preparations for treating infertility. While currently available preparations work well in young women, they become increasingly ineffective in older women, requiring higher doses and prolonged administration yet producing fewer oocytes.

描述（由申请人提供）：申请5年资助，研究垂体-卵巢轴衰老。我们试图通过促卵泡激素（FSH）了解垂体-卵巢的交流。众所周知，35岁以上妇女的生育能力比年轻妇女下降。不孕不育诊所报告老年妇女对外源性卵泡刺激素制剂的反应性下降。该项目将重点关注衰老卵巢对两种主要人类(h)卵泡刺激素糖型相对丰度变化的反应。具有α亚基和β亚基低聚糖的经典hFSH被命名为四糖基化hFSH，而仅具有α亚基低聚糖的新型hFSH被命名为二糖基化hFSH。21-24岁的女性表达二糖基化的hFSH多于四糖基化的hFSH，围绝经期女性表达二糖基化的hFSH略少，而绝经后女性主要表达四糖基化的hFSH。项目1将研究月经周期中与年龄增长相关的三氢谷胱甘肽糖型相对丰度的变化，并研究糖调节FSH受体结合和激活的机制。项目2将比较hFSH糖型在卵巢多种信号转导实验中的活性，以确定提高二糖基化hFSH生物活性的可能机制。两种糖型对骨吸收的不同影响也将被研究。项目3将创建小鼠模型，以验证两种hFSH糖型对生殖功能都是必需的假设。双hFSH糖基化突变体将取代正常的mFSH基因。这条线将与FSH缺失的小鼠杂交，看看它是否能挽救雌性不育。纯化的hFSH糖型也将在无FSH小鼠体内进行测试。华盛顿州立大学FSH工艺核心实验室（core B）将为所有项目提供特性良好的纯化hFSH糖型。最初的产品将是二糖基化hFSH和四糖基化hFSH，这是所有科学项目感兴趣的，但无法从其他来源获得。由于天然来源的丰度较低，重组二糖基化hFSH将首先表达。核心B将表征每个占用的n -糖基化位点的聚糖群，从而提供具有已知而不是假设的糖基化差异的完全表征的糖型。Core B还将为项目研究人员提供细胞培养和分析服务。WSU生物信息学核心（core C）将通过互联网为所有研究人员提供一个易于访问的数据共享平台。这项研究的结果将是更好地理解卵巢反应性随着年龄的增长而降低的机制，这可能会导致开发更有效的FSH制剂来治疗不孕症。虽然目前可用的制剂在年轻女性中效果良好，但它们在老年女性中越来越无效，需要更高的剂量和更长时间的给药，但产生的卵母细胞却更少。