Integrated analyses of the seasonally quiescent ovary and female reproductive aging

Cornell Univ - State: Awds Made Prior May 2010, Ithaca NY

Investigators

Abstract

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.