Polycystic ovarian syndrome: insights into the enigma that is PCOS today

Serum anti-Mullerian hormone predicts ovarian response in (Macaca fascicularis) monkeys

AMH as a promising predictor of ovarian response has been studied extensively in women undergoing assisted reproductive technology treatment, but little is known about its prediction value in monkeys undergoing ovarian stimulation. In the current study, a total of 380 cynomolgus monkeys ranging from 5 to 12 years received 699 ovarian stimulation cycles. Serum samples were collected for AMH measure with enzyme-linked immunosorbent assay. It was found that serum AMH levels were positive correlated with the number of retrieved oocytes (P < 0.01) in the first, second and third stimulation cycles. In the first cycles, area under the curve (ROCAUC) of AMH is 0.688 for low response and 0.612 for high response respectively, indicating the significant prediction values (P = 0.000 and P = 0.005). The optimal AMH cutoff value was 9.68 ng/mL for low ovarian response and 15.88 ng/mL for high ovarian response prediction. In the second stimulation cycles, the significance of ROCAUC of AMH for high response rather than the low response was observed (P = 0.001 and P = 0.468). The optimal AMH cutoff value for high ovarian response was 15.61 ng/mL. In the third stimulation cycles, AMH lost the prediction value with no significant ROCAUC. Our data demonstrated that AMH, not age, is a cycle-dependent predictor for ovarian response in form of oocyte yields, which would promote the application of AMH in assisted reproductive treatment (ART) of female cynomolgus monkeys. AMH evaluation would optimize candidate selection for ART and individualize the ovarian stimulation strategies, and consequentially improve the efficiency in monkeys.

Thecal cell sensitivity to luteinizing hormone and insulin in polycystic ovarian syndrome

This study examined whether a defect of steroid synthesis in ovarian theca cells may lead to the development of PCOS, through contributions to excess androgen secretion. Polycystic ovarian syndrome (PCOS) is one of the leading causes of infertility worldwide affecting around 1 in 10 of women of a reproductive age. One of the fundamental abnormalities in this syndrome is the presence of hormonal irregularities, including hyperandrogenemia, hyperinsulinemia and hypersecretion of luteinizing hormone (LH). Studies suggest that insulin treatment increases progesterone and androstenedione secretion in PCOS theca cells when compared to insulin treated normal theca cells. Furthermore the augmented effects of LH and insulin have been seen to increase ovarian androgen synthesis in non-PCOS theca cultures whilst also increasing the expression of steroidogenic enzymes specific to the PI3-K pathway. Our examination of primary thecal cultures showed an increase in both the expression of the steroidogenic enzyme CYP17 and androgen secretion in PCOS theca cells under basal conditions, when compared to non-PCOS cells. This was increased significantly under treatments of LH and insulin combined. Our results support the previous reported hypothesis that a dysfunction may exist within the PI3-K pathway. Specifically, that sensitivity exists to physiological symptoms including hyperinsulinemia and hyper secretion of LH found in PCOS through co-stimulation. The impact of these findings may allow the development of a therapeutic target in PCOS.

Defective CFTR-regulated granulosa cell proliferation in polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is one of the most frequent causes of female infertility, featured by abnormal hormone profile, chronic oligo/anovulation, and presence of multiple cystic follicles in the ovary. However, the mechanism underlying the abnormal folliculogenesis remains obscure. We have previously demonstrated that CFTR, a cAMP-dependent Cl(-) and HCO3 (-) conducting anion channel, is expressed in the granulosa cells and its expression is downregulated in PCOS rat models and human patients. In this study, we aimed to investigate the possible involvement of downregulation of CFTR in the impaired follicle development in PCOS using two rat PCOS models and primary culture of granulosa cells. Our results indicated that the downregulation of CFTR in the cystic follicles was accompanied by reduced expression of proliferating cell nuclear antigen (PCNA), in rat PCOS models. In addition, knockdown or inhibition of CFTR in granulosa cell culture resulted in reduced cell viability and downregulation of PCNA. We further demonstrated that CFTR regulated both basal and FSH-stimulated granulosa cell proliferation through the HCO3 (-)/sAC/PKA pathway leading to ERK phosphorylation and its downstream target cyclin D2 (Ccnd2) upregulation. Reduced ERK phosphorylation and CCND2 were found in ovaries of rat PCOS model compared with the control. This study suggests that CFTR is required for normal follicle development and that its downregulation in PCOS may inhibit granulosa cell proliferation, resulting in abnormal follicle development in PCOS.

The circadian variation in Anti-Müllerian hormone in patients with polycystic ovary syndrome differs significantly from normally ovulating women

Obective

To improve the biologic understanding of the Polycystic Ovarian Syndrome (PCOS) condition by examining the circadian variation and relationship between Anti Müllerian Hormone (AMH), gonadotropins and ovarian steroids in PCOS patients compared to normally ovulating and menstruating women. By comparing the pattern of co-variation between AMH and Luteinizing Hormone, two compounds closely linked to hyperandrogenism and anovulation in PCOS, the involvement of the Hypothalamic-Pituitary-Ovarian axis in PCOS pathology could be elucidated.

Patients

Eight normal-weighted young, anovulatory PCOS-women as study group and ten normal menstruating and ovulating women as controls.

Interventions

Observational prospective study of the circadian variation in AMH, gonadotropins, sex steroids and androgens in a study and a control group. A circadian profile was performed in each study and control subject during a 24-h period by blood sampling every second hour, starting at 8:00 a.m. and continuing until 8:00 a.m. the following day.

Result(s)

Significant differences in hormonal levels were found between the groups, with higher concentrations of AMH, LH and androgens in the PCOS group and lower amounts of FSH and progesterone. A distinct difference in the circadian variation pattern of AMH and LH between PCOS patients and normal controls was seen, with PCOS patients presenting a uniform pattern in serum levels of AMH and LH throughout the study period, without significant nadir late-night values as was seen in the control group. In PCOS women, a significant positive association between LH/ FSH and testosterone was found opposite to controls.

Main outcome measures

Circadian variation in Anti-Müllerian Hormone, gonadotropins and ovarian steroids and the covariation between them.

Conclusion

A significant difference in the circadian secretion of LH and AMH in PCOS women compared to normally ovulating women indicate an increased GnRH pulse, creating high and constant LH serum concentrations. A significant co-variation between LH and AMH may suggest LH as a factor involved in the control of AMH secretion.