Oocyte genomic instability as a driver of the aging ovarian innate immune response

项目摘要 整体组织功能随着年龄的增长而恶化，但女性生殖系统是第一个老化的。女性 生殖老化的特征在于导致流产的卵子数量和质量下降， 不孕不育和先天缺陷更年期生殖功能的停止也加速了整体衰老 因为性腺激素，雌激素，调节许多组织（例如，大脑心脏骨骼免疫细胞 生殖道）。女性生殖老化的后果是显著的，因为女性正在推迟 生育和医疗干预增加了更年期和寿命之间的差距。因而 是发现女性生殖衰老的分子机制的迫切需要。的标志 老化组织是先天免疫系统的“炎症”或慢性生理刺激， 随着年龄的增长，无菌性炎症的水平。邓肯和格顿实验室最近发现了一个突出的 老化卵巢中的炎症信号，包括卵泡体细胞室（颗粒细胞） 以及基质或组织微环境中。然而，这种与年龄相关的卵巢癌的机制 炎症的产生、持续和跨细胞类型的传播是未知的，必须解决 推进领域。我们的长期目标是发现女性生殖衰老的分子调节因子， 配子，卵泡和卵巢微环境的观点。因此，我们的应用程序与 NICHD的生育和不育分支高度优先研究领域的生殖过渡。主要目的 这项资助的主要目的是发现卵母细胞与其周围颗粒细胞之间的信号交换，以及它们是如何相互作用的。 细胞间通讯驱动卵巢衰老的更广泛的时空模式。我们的总体 一种假设是，随着生育年龄的增长，细胞质DNA来源于基因组稳定性的丧失， 卵母细胞刺激卵巢颗粒细胞中的先天免疫应答和炎症途径， 然后被组织微环境进一步放大。我们模型的核心是cGAS-STING途径 其将组织内细胞的基因组不稳定性和炎症反应联系起来。这条路从来没有 在卵巢中进行了检查，也没有在卵巢老化的背景下，但我们的初步数据强烈支持 基本作用。为了解决我们的总体假设，我们将确定年龄相关的基因组不稳定性， 小鼠卵母细胞中作为触发信号的特征（Aim 1）。然后我们将确定颗粒细胞 整合来自卵母细胞的信号以启动年龄相关的先天免疫应答（Aim 2）。最后我们将 发现卵巢纤维化和炎症的时空结构如何支配卵泡反应 反之亦然，通过空间转录组学（目的3）。这些目标将提供全面和综合的 高时空分辨率下炎症的分子机制，考虑配子、卵泡和 卵巢积极的影响将是发现新的分子途径，可以靶向细胞 类型特异性的方式来提高配子质量，生殖寿命和健康寿命。

PROJECT SUMMARY Overall tissue function deteriorates with age, but the female reproductive system is the first to age. Female reproductive aging is characterized by a decline in egg quantity and quality which contributes to miscarriages, infertility, and birth defects. Cessation of reproductive function at menopause also accelerates overall aging because the gonadal hormone, estrogen, regulates numerous tissues (e.g., brain, heart, bone, immune cells, reproductive tract). The consequences of female reproductive aging are significant because women are delaying childbearing, and medical interventions have increased the gap between menopause and lifespan. Thus there is a critical need to discover the molecular mechanisms underpinning female reproductive aging. A hallmark of aging tissues is “inflammaging” or chronic physiologic stimulation of the innate immune system leading to low levels of sterile inflammation with age. The Duncan and Gerton laboratories recently discovered a prominent inflammatory signature in the aging ovary, both within the somatic compartment of the follicle (granulosa cells) and in the stroma or tissue microenvironment. However, the mechanism by which this age-related ovarian inflammation is generated, sustained, and propagated across cell types is not known and must be addressed to advance the field. Our long-term goal is to discover the molecular regulators of female reproductive aging from perspectives of the gamete, follicle, and ovarian microenvironment. Thus, our application is aligned with the NICHD’s Fertility and Infertility Branch high-priority research area of reproductive transitions. The major objective of this grant is to discover signals exchanged between oocytes and their surrounding granulosa cells, and how intercellular communication drives the broader spatiotemporal pattern of ovarian aging. Our overarching hypothesis is that, with advanced reproductive age, cytosolic DNA originating from loss of genomic stability in the oocyte stimulates the innate immune response and inflammatory pathways in ovarian granulosa cells which are then further amplified by the tissue microenvironment. Central to our model is the cGAS-STING pathway which links genomic instability and inflammatory responses across cells within a tissue. This pathway has never been examined in the ovary, nor within the context of ovarian aging, but our preliminary data strongly support a fundamental role. To address our overarching hypothesis, we will identify age-associated genomic instability signatures in the mouse oocyte that serve as trigger signals (Aim 1). We will then determine how granulosa cells integrate oocyte-derived signals to initiate an age-associated innate immune response (Aim 2). Finally, we will discover how the spatio-temporal architecture of ovarian fibrosis and inflammaging govern the follicular response and vice versa through spatial transcriptomics (Aim 3). These aims will provide a comprehensive and integrated molecular mechanism of inflammaging at high spatial temporal resolution that considers the gamete, follicle, and the ovary. The positive impact will be the discovery of novel molecular pathways that could be targeted in cell type-specific manners to improve gamete quality, reproductive longevity, and healthspan.