Insulin Resistance in Polycystic Ovary Syndrome

Abstract

Polycystic ovary syndrome (PCOS) is the commonest endocrine dis order in women of reproductive age and now recognized as an important metabolic and reproductive disor der. The majority of women with PCOS have insulin resistance and this is regarded to have a central etiological role in PCOS. Insulin resistance and concomitant hyperinsulinemia modifies reproductive function by driving androgen production, suppression of sex hormone-binding globulin (SHBG) and disruption of insulin signaling pathways in the central nervous system. Insulin resistance, together with defects in insulin secretion, confers markedly increased risk for type 2 diabetes mellitus and metabolic syndrome. There are post-binding defects in insulin receptor signaling, with selective resistance to insulin's metabolic actions and preserved other actions. Genetic and environmental abnormalities interact to produce peripheral insulin resistance in PCOS. The numerous in vivo and in vitro data supporting the central role of insulin resistance in the pathogenesis of PCOS have led a new therapy for PCOS with insulin-sensitizing agents. (KOREAN DIABETES J 32:1~6, 2008)