MON-LB038 Reduced Exercise Endurance And Skeletal Muscle Alterations In A Prenatally Androgenized Rat Model For Polycystic Ovary Syndrome

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women, impacting female reproductive, cardiometabolic, and psychological health. Studies of metabolic dysfunction in women with PCOS have primarily focused on adipose tissue and obesity-related changes. Some studies have reported changes in lean body mass and muscle function in women with PCOS. OBJECTIVE: To determine if prenatally androgenized (PNA) female rats exhibit altered exercise endurance or differences in skeletal muscle mass or morphology compared to control rats. METHODS: Sprague-Dawley rats were prenatally exposed to 5 mg testosterone or vehicle alone from gestational days 16-19. At 15 weeks of age, females were subjected to rotarod time trials as a measure of exercise endurance. At 16 weeks of age, hindlimb skeletal muscle mass, fiber cross-sectional area (CSA), and fiber composition were determined. Expression of ATP synthase was also investigated. RESULTS: Compared with controls, PNA female rats demonstrated greater total body and hindlimb muscle weights, and trends toward diminished time on the rotarod, as well as greater type II muscle fiber composition and levels of ATP synthase in the gastrocnemius. No changes were observed in gastrocnemius or soleus muscle fiber CSA, or in soleus fiber type composition or ATP synthase expression. CONCLUSIONS: PNA female rats exhibit changes in gastrocnemius muscle that are consistent with a change in muscle fiber composition, which may affect exercise endurance. Findings in this rat model for PCOS are consistent with findings in women with the disorder. Sources of Research Support: LECOM institutional funding to DS. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.