P-232: Evaluation of Cilostamide Efficiency in Comparison with Forskolin on The Two-Step In Vitro Maturation of Mice Germinal Vesilce Oocytes

Background: The effects of cumulus cells and the effectiveness of a PDE3 specific inhibitor (Cilostamide) in comparison with an adenylate cyclase activator (Forskolin) on the maturation rate and developmental competence of mouse germinal vesicle (GV) oocytes were evaluated Materials and Methods: Germinal vesicles (GV) oocytes of PMSG-primed mice were divided into cumulus denuded oocytes (CDOs) and cumulus oocyte complexes (COCs) groups. GV oocytes were cultured in TCM199 (I) without any treatment only for 24 hours (control); (II) supplemented with 10 uM Cilostamide for 48 hours and (III) supplemented with 50 uM Forskolin for 48 hours. Metaphase II oocytes achieved following 24 hours (control; one-step manner) and 48 hours (biphasic culture; with meiotic inhibitors from 0 to 24 hours, no meiotic inhibitors from 24 to 48 hours) were subject to in vitro fertilization (IVF) and embryos were cultured. Results: Immature oocytes cultured with Forskolin and Cilostamide in biphasic manner showed a significantly higher (p<0.05) maturation, fertilization and two cells embryo rates in COCs and CDOs compared to their control groups, while no significant difference was observed between Forskolin and Cilostamide in both COCs and CDOs groups (p>0.05). Despite the significant difference (p<0.05) between COCs and CDOs in the control group, this difference was not observed in the two-step culture in the presence of Forskolin or Cilostamide. Conclusion: In vitro maturation with Cilostamide and Forskolin in biphasic manner positively influences GV oocyte developmental competence and are more effective in CDOs than COCs groups