Insight Towards Induction of Reproductive-Metabolic Phenotypes of Polycystic Ovarian Syndrome

Abstract

Hormonal disturbances, multiple ovarian cysts, and oligo-anovulation are the key features of the polycystic ovarian syndrome (PCOS). Consistently, without a directly hormone-regulated animal model, we developed three phenotypes of PCOS in rats to simulate the reproductive-metabolic disturbances of human PCOS. Twenty-four female Sprague-Dawley rats underwent vaginal smears for two sequential cycles to exclude any PCOS-like rats. Rats were divided into the following groups: healthy control, PCOS induced by a high-fat, high-sugar (HFHS) diet, PCOS induced by HFHS diet +monosodium glutamate (MSG), and PCOS induced by continuous light exposure (L/L). At the end of the study, an abdominal ultrasound revealed multiple ovarian cysts, and a vaginal smear documented the arrest of the estrous cycle. Serum samples showed hyperinsulinemia and hyperandrogenism in all PCOS-induced groups, but with superiority of the L/L group in developing higher insulin levels, insulin resistance, and anti-Müllerian hormone (AMH). Although the frequency of isolated uterine contractions increased in all modeling groups compared to the control, the contraction amplitude was higher in HFHS than in L/L and HFHS-MSG groups. The three animal models manifested the key features of PCOS and symptoms of metabolic syndrome. Disturbed circadian rhythm and HFHS diet are more in line with the increased risk of PCOS.