5α-dihydrotestosterone treatment induces metabolic changes associated with polycystic ovary syndrome without interfering with hypothalamic leptin and glucocorticoid signaling

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy in women of reproductive age. It is a heterogenous disorder, with hyperandrogenism, chronic anovulation and polycystic ovaries as basic characteristics, and associated metabolic syndrome features. Increased secretion of leptin and leptin resistance are common consequences of obesity. Leptin is a hormone with anorexigenic effects in the hypothalamus. Its function in the regulation of energy intake and consumption is antagonized by glucocorticoids. By modulating leptin signaling and inflammatory processes in the hypothalamus, glucocorticoids can contribute to the development of metabolic disturbances associated with central energy disbalance. The aim of the study was to examine the relationship between hypothalamic leptin, glucocorticoid and inflammatory signaling in the development of metabolic disturbances associated with PCOS. The study was conducted on an animal model of PCOS generated by a continual, 90-day treatment of female rats with 5?-dihydrotestosterone (DHT). The model exhibited all key reproductive and metabolic features of the syndrome. mRNA and/or protein levels of the key components of hypothalamic glucocorticoid, leptin and inflammatory pathways, presumably contributing to energy disbalance in DHT-treated female rats, were measured. The results indicated that DHT treatment led to the development of hyperphagia and hyperleptinemia as metabolic features associated with PCOS. However, these metabolic disturbances could not be ascribed to changes in hypothalamic leptin, glucocorticoid or inflammatory signaling pathways in DHT-treated rats.