8795 Impact of Retinoic Acid Receptor Alpha Conditional Knockout on Ovarian Follicle Development in the Mouse

Abstract Disclosure: Z. Bogin: None. A. Keisker: None. A. Urbanowski: None. C. White: None. J.L. Kipp: None. The ovaries are the primary endocrine and reproductive organs in females. The ovarian follicle is the basic structural and functional unit of the ovary. When there is abnormal development in ovarian follicles, infertility and reproductive diseases such as polycystic ovarian syndrome (PCOS), premature ovarian failure (POF), and ovarian cancers may occur. Retinoic acid (RA), a biologically active derivative of vitamin A, is a signaling molecule that plays a vital role in various physiological processes, including embryonic development, tissue differentiation, and reproduction. We have shown that RA stimulates granulosa cell proliferation through a cell signaling cascade involving Retinoic Acid Receptors (RARs), which have three isoforms alpha, beta, and gamma. In this study, we characterized a new retinoic acid receptor alpha conditional knockout (RARA cKO) mouse model with RARA deleted in granulosa cells during embryonic development. The body weight and uterus weight of the RARA cKO mice were decreased at week 7 but returned to normal at week 15 and 12 months. The animals were either sub-fertile or infertile with phenotypic evidence of POF. In addition, a variety of ovarian pathologies were observed, including the presence of hemosiderin, increased cyst formation, and abnormal follicle counts. Overall, this study provides evidence of the involvement of retinoic acid signaling, mediated by RARA, in ovarian development and fertility. This study will help to better understand the prevention and treatment of ovarian diseases. Presentation: 6/2/2024