Altered Stem Cell Receptor Activity in the Ovarian Surface Epithelium by Exogenous Zinc and/or Progesterone.

BACKGROUND: Ovarian surface epithelium (OSE) has the characteristics of a stem cell and the potential for differentiation. Previous studies on this subject have succeeded in deriving oocytes from OSE stem cells, leading to the belief that OSE could be used for infertility treatment. METHODS: Each rat (n = 10) was subjected to zinc and/or progesterone injection for 5 days after conception. After a 6-day implantation period, ovarian tissues were removed and comprehensive immunohistochemical analysis of stem cell markers was conducted: Sox2, Klf4, Oct3/4, c-Myc, CD117, CD90, SSEA-1 and Notch pathway analysis; Notch1, Jagged1, and Delta1 in the OSE and ovarian stromal cells were evaluated after treatment with zinc, progesterone, or both. RESULTS: Progesterone moderately affected Sox2 expression (p < 0.001), while zinc application strongly affected Klf4 and Oct3/4 and immunoreactivity (p < 0.001). CD90 immunoreactivity was decreased in the OSE and stroma of the progesterone group (p = 0.006) compared with the zinc (p = 0.244) and zinc/progesterone groups (p = 0.910). On the other hand, SSEA-1 showed moderate staining in the OSE and weak staining in stromal cells in animals treated with zinc (p = 0.727), progesterone (p = 0.626), and zinc/progesterone (p = 0.371), with no differences compared with control. Zinc application affected Notch pathway immunoreactivity, with a significant increase in Notch1 (p = 0.0015) and Jagged1 (p < 0.001). CONCLUSIONS: The expression of putative stem cell markers in the OSE was verified and stem cell receptor activity was raised in the OSE and ovarian stromal cells by zinc and progesterone. Thus, this increased expression allows the therapeutic use of zinc and progesterone in ovary-related infertility and brings a different perspective to reproductive medicine.

Complete down-regulation is not mandatory for good assisted reproductive treatment cycle outcomes.

OBJECTIVE: To determine the implications and predictive value of estradiol concentrations following pituitary down-regulation with gonadotrophin releasing hormone agonists in women undergoing controlled ovarian hyperstimulation for assisted reproductive technology. STUDY DESIGN: A total of 277 patients undergoing ovarian hyperstimulation for intracytoplasmic sperm injection (ICSI) were enrolled into the study and the patients were divided into four groups according to estradiol levels on the initial day of stimulation of which group-A consisted of the patients who had < or =25 pg/ml (n=90), group-B with levels between 26 and 50 pg/ml (n=104), group-C with levels between 51 and 75 pg/ml (n=67) and group-D with levels > or =76-90 pg/ml (n=16) and the results were compared. The primary outcome measures included ovarian response and the clinical pregnancy rates. RESULTS: The clinical pregnancy rates in groups-A, B, C and D were 33.3% (30/90), 26.0% (27/104), 35.8% (24/67), and 25.0% (4/16), respectively, and there was no statistically significant difference (P=0.482). The mean number of oocytes retrieved in groups were (9.7+/-5.8, 10.3+/-6.5, 11.0+/-6.8, and 12.1+/-6.6), respectively (P=0.453) and the fertilization rates in groups-A, B, C and D were found to be similar (75, 80, 73 and 79%, respectively; P=0.658). CONCLUSION: Complete and deep desensitization obviously seems not to be mandatory for successful stimulation in assisted reproductive technology cycles.