Decreased Sirtuin1 Protein and Aromatase Activity Index in Follicular Fluid is Correlated with Increased Germinal Vesicle Count in Polycystic Ovary Syndrome

The close interaction of follicular fluid with oocytes influences their maturation. The presence of the germinal vesicle (GV) has been reported in women with polycystic ovary syndrome (PCOS). The present study aimed to measure sirtuin1 (SIRT1) levels, aromatase activity index and insulin resistance in follicular fluid and to investigate their association with in vitro fertilization (IVF) success in PCOS women. In this case-control study, 35 women with PCOS and 35 healthy women matched for body mass index (BMI) were included. After the collection of the follicular fluid from all participants, concentrations of SIRT1, insulin, and aromatase activity were measured. Retrieved oocyte status, embryo quality, and biochemical pregnancy were monitored during follow-up in the participants. In women with PCOS, there were notable reductions in SIRT1 levels and aromatase activity, along with an increase in the HOMA- Index. Negative correlations were observed between SIRT1 and aromatase activity with the number of GVs. SIRT1 concentration and aromatase activity showed positive correlation with the ratio of available embryos to the number of oocytes in metaphase II. Logistic regression analysis showed that chance of biochemical pregnancy increases significantly with an increase in aromatase activity and SIRT1 level in follicular fluid (p<0.05). Our findings showed that the reduced SIRT1 level and aromatase activity in follicular fluid are involved with the pathogenesis of PCOS. These findings suggest that increasing in aromatase activity and SIRT1 levels may improve oocytes quality and ultimately increase the chances of IVF success in PCOS women.