Supraphysiological leptin levels shift the profile of steroidogenesis in porcine ovarian follicles toward progesterone and testosterone secretion through increased expressions of CYP11A1 and 17β-HSD: a tissue culture approach

Abstract

Evidence from both clinical and animal studies suggests that exposure to excess androgens results in cyst formation. The present in vitro study assessed the effects of supraphysiological concentrations of leptin (20 and 40 ng/ml) on progesterone (P4), androstenedione androstendione (A4), testosterone and estradiol (E2) secretion by ELISA and the expression of CYP11A1, CYP17, 17β-hydroxysteroid dehydrogenase (17β-HSD) and CYP19 by western blot to answer the question of whether leptin could be independent risk factor for cyst formation in pigs. Small- and medium-sized ovarian follicles were collected from prepubertal and cycling pigs. Increased P4 and testosterone secretions were observed in both small- and medium-sized follicles in prepubertal and cycling animals whereas there was no change in E2 secretion. Leptin treatment resulted in an increase in CYP11A1 and 17β-HSD protein expression but had no effect on CYP17 and CYP19 expression in follicles of either size from prepubertal and cycling pigs. Results of presented data suggest that leptin in elevated doses, by stimulatory effect on CYP11A1 and 17β-HSD protein expression resulting in elevated P4 and testosterone secretions could be an independent risk factor for cyst formation in both prepubertal and cycling pigs.