"Hormone of darkness" and human reproductive process: direct regulatory role of melatonin in human corpus luteum.

PURPOSE: To investigate the possible role of melatonin on human luteal cell function. METHODS: Corpora lutea were obtained from normally menstruating women (25-38 years old) in the midluteal phase (days 5-6 from ovulation) at the time of surgery for non-endocrine gynecologic diseases. The protocol was approved by the institutional review board of Università Cattolica del Sacro Cuore in Rome and all patients provided written informed consent. The corpora lutea were dated on the basis of the presumptive day of ovulation (day 0) , determined by urinary luteinizing hormone (LH) peak, ultrasound detection of corpus luteum or disappearance of the dominant follicle, and a rise in the plasma P concentration. ELISA or EIA kit and immunohistochemistry were performed. RESULTS: Melatonin was able to increase progesterone release and to influence the balance between luteotrophic and luteolityc factors. In addition, melatonin expression and MT2 receptor were detected, confirming the direct action of this indoleamine on CL. CONCLUSIONS: Melatonin may play an intriguing role in direct regulation of CL function and in establishing and maintaining of initial pregnancy. In conclusion, melatonin could become a relevant medication for improving ovarian and luteal function and in the early stages of pregnancy, opening new opportunities for the management of several ovarian-luteal and pregnancy diseases.

Increased fibulin-1 plasma levels in polycystic ovary syndrome (PCOS) patients: possible contribution to the link between PCOS and cardiovascular risk.

PURPOSE: To investigate a possible relation between fibulin-1 plasma levels and PCOS. DESIGN: ELISA quantitative determination of human fibulin-1. METHODS: 50 women with PCOS and 40 control patients who attended the Unit of Human Reproductive Pathophysiology, Università Cattolica del Sacro Cuore, Rome, were enrolled. Ultrasonographic pelvic examinations, hormonal profile assays, oral tolerance test OGTT, lipid profile and ELISA quantitative determination of human fibulin-1 were performed. RESULTS: Fibulin-1 levels were found to be statistically significantly higher in PCOS patients than in matched control women. No statistically significant positive correlation was found between fibulin-1 and AUCi, HOMA-IR, total cholesterol, LDL, AMH, androstenedione and FAI, whereas a statistically significant positive correlation was found between fibulin-1 and 17OHP (p = 0.016) in the PCOS group. However, multivariable linear regression analysis showed that 17 OH P did not independently predict fibulin-1 levels (p = 0.089). CONCLUSIONS: Our data could contribute to explain the hypothesized increased cardiovascular risk and vascular damage in patients with PCOS. A better understanding of the cellular and molecular mechanisms involved in cardiometabolic disorders associated with PCOS is mandatory to identify new therapeutic strategies to eventually prevent the progression of cardiovascular diseases in these patients.