Inhibin-activin-follistatin System: Relationship To Polycystic Ovary Syndrome And Ovarian Functions

Objective: To explore the abnormalities of serum inhibinB, activinA and follistatin concentrations in patients with polycystic ovary syndrome (PCOS).Methods: Serum levels of inhibinB, activinA and follistatin on cycle day 3 were determined by a solid quantitative sandwich enzyme immunoassay technique (Sandwich ELISA) both in PCOS group and in controls (womem with regular cycle) , and relationship between the two groups and with other sex hormone, body-mass-index (BMI), insulin and glucose were analyzed.Results: Mean (+SEM) concentrations of inhibinB were higher (P<0.001) in PCOS (290 + 86) pg/ml than controls (172 + 53) pg/ml and activinA were lower (P< 0.05) in PCOS (545+44) pg/ml than controls (588 + 89) pg/ml. In PCOS women, Concentrations of follistatin were higher (P=0.01) in PCOS (1317 + 392) pg/ml than controls (804 + 203) pg/ml. In PCOS women, nonparametric correlations analysis demonstrated that inhibinB serum levels were positively correlated with insulin and glucose (r=0.436 and r=0.618, respectively; P<0.05 and P<0.05, respectively) and activinA were negatively correlated with insulin (r=-0.442, P<0.05). All of them have no significant associations with BMI.Conclusion: Extraordinary paracrine or autocrine of inhibin-activin-follistatin system may be partly responsible for the lack of pre-ovular follicle development in PCOS and it is obvious that higher concentrations of inhibinB with lower concentrations of activinA may relate to hyperinsulinemia.