Effect of resistin on estradiol and progesterone secretion from human luteinized granulosa cells in culture

Abstract

ABSTRACT Information on the role of resistin on steroidogenesis is limited to animal studies. The aim of this study was to investigate the effect of various doses of resistin on estradiol and progesterone secretion from human luteinized granulosa cells in culture. Granulosa cells were obtained from follicular fluid aspirated from 50 women undergoing in vitro fertilization (IVF) treatment. The cells were cultured for 48 h after a 24 h pre-incubation period. The effect of resistin at dosages 1, 10 and 100 ng/ml alone or in combinations with FSH (10 and 100 ng/ml) on steroidogenesis was investigated. Estradiol and progesterone were measured by radioimmunoassays in culture supernatants at 24 h and 48 h. FSH treatment increased both estradiol and progesterone secretion. Resistin suppressed basal estradiol (at 1 ng/ml) and progesterone secretion (at all concentrations tested). When resistin (all concentrations) was combined with FSH (100 ng/ml), it eliminated the stimulatory effect of FSH on the secretion of estradiol and progesterone. This study indicates an inhibitory effect of resistin on the secretion of estradiol and progesterone by human luteinized granulosa cells in vitro. It is likely that this adipokine locally affects ovarian function in women. Abbreviations: 3β-HSD: 3β-hydroxysteroid dehydrogenase; CAP1: cyclase-associated protein 1; DCN: decorin; FIZZ: Found in Inflammatory Zones; hCG: human chorionic gonadotropin; IGF1: insulin-like growth factor type 1; IVF: in vitro fertilization; PCOS: polycystic ovary syndrome; RIA: radioimmunoassay; ROR1: receptor tyrosine kinase-like orphan receptor-1; TLR4: Toll–like receptor 4