Integrated analyses of the seasonally quiescent ovary and female reproductive aging

在繁殖季节之外，诸如静止、抑制和不活跃等术语经常被用来描述季节性繁殖哺乳动物的卵巢状态。然而，最近的发现表明，所谓的静止卵巢出现了重要的结构和功能变化，这些变化似乎调节着生殖衰老过程。更具体地说，维持西伯利亚雌性仓鼠的短光周期与卵巢的深刻变化有关，这些变化似乎表现为生殖衰老减速。短日照引起的变化的结果包括提高生育力和保护老年女性的卵泡。因此，在不利于繁殖的条件下停止排卵活动不应等同于卵巢不活动。这项研究项目将改变和告知我们对季节性静止的卵巢的看法，并提供更好的了解它在生殖衰老中的作用。综合分析将确定光周期诱导的脑下垂体激素分泌的变化是否以及如何有助于短日照卵巢表型的发展。由于褪黑激素是松果体分泌的一种激素，在季节性繁殖的哺乳动物中参与短光周期的影响，因此研究将确定褪黑激素的缺失是否与卵巢衰老的加速有关。这项研究的更广泛影响在于它将受训人员纳入调查的所有方面，并特别努力吸引妇女和代表不足的少数群体进入实验室。我们的实验结果将引起广大科学家的兴趣，包括生殖生物学家、生态学家、时间生物学家和老年学家。由于女性将第一个孩子推迟到较高生育年龄的趋势持续存在，我们的结果可能会对社会产生重要影响，因为对女性生殖老化的洞察可能适用于所有哺乳动物物种，包括我们自己。

Terms such as quiescent, inhibited, and inactive are often used to describe the state of the ovaries in seasonally breeding mammals when considered outside of the breeding season. However, recent findings have demonstrated important structural and functional changes in the so-called quiescent ovary that appear to modulate the reproductive aging process. More specifically, maintaining female Siberian hamsters in short photoperiod is associated with profound changes of the ovary that appear to manifest as decelerated reproductive aging. The outcomes of the short-day-induced changes include improved fertility and a preservation of ovarian follicles in older females. Therefore, the cessation of ovulatory activity under conditions that do not favor breeding should not be equated with ovarian inactivity. This research project will transform and inform our thinking about the seasonally quiescent ovary and provide a better understanding of its role in reproductive aging. Integrative analyses will determine if and how photoperiod-induced changes in hormone secretion from the pituitary gland contribute to the development of the short-day ovarian phenotype. Because melatonin, a hormone secreted by the pineal gland, mediates the effects of short photoperiod in seasonally breeding mammals, research will determine if the absence of melatonin is associated with an acceleration of ovarian aging. The broader impact of this research lies in its inclusion of trainees in all aspects of the investigation, with a special effort made to attract women and underrepresented minorities to the lab. The results of our experiments will be of interest to a broad array of scientists, including reproductive biologists, ecologists, chronobiologists, and gerontologists. Because there is a continuing trend for women to delay having their first child until an advanced reproductive age, our results may have important implications for society, as insights into female reproductive aging may be applicable to all mammalian species, including our own.