RESUMEN
OBJECTIVE: Some reports have indicated that conditioned medium from growing mouse embryonic stem cells (ESCs) provides a supportive condition for small follicles growing, oocyte maturation, and following embryo growth. The aim of this study is assessing in vitro maturation (IVM) and consequent in vitro fertilization (IVF) outcome of immature mouse oocytes using human embryonic stem cells conditioned medium (HESCM). MATERIALS AND METHODS: In this experimental study, 240 germinal vesicle (GV) oocytes were took from NMRI female mice, aged 4-6 weeks, 48 hours before injection of 5 IU pregnant mare serum gonadotropin (PMSG). 120 GV oocytes without cumulus cells were cultured in each of the groups. 120 GV were cultured in HESCM as test groups and also 120 GV cultured in human embryonic stem cells medium (HESM) as control groups. After evaluating the metaphase II (MII) oocyte maturation rate at 8, 16 and 24 hours, the MII oocytes subsequently were fertilized in vitro and the two-cell embryo development rate was recorded at days 1, 2, and 3. Statistical analysis was performed by using the generalized estimating equations (GEE) method that calculated their rate ratio. RESULTS: Our data indicated there are significant differences between the maturation rates in HESCM and HESM (P=0.004), also the two-cell embryo development was significant between two culture media (P=0.00). CONCLUSION: Similar to some other studies, the secretome of the HESCM showed a significant impact on the IVM outcomes in mice.
RESUMEN
BACKGROUND: To increase the results of infertility treatment, many efforts have been made to improve the treatment methods. As assisted reproductive technology is mainly using cell culture methods, one of the approaches to improve this technology is conditioned medium from different sources. It is desirable to apply in vitro maturation (IVM) and use oocytes from normal cycles instead of stimulating ovulation. OBJECTIVE: To investigate the effect of human cumulus cell condition medium (hCCCM) on the IVM of immature mouse oocytes and morphology. MATERIALS AND METHODS: In this experimental study, 240 germinal vesile oocytes were collected from four-six wk-old mice after 48 hr of 5IU pregnant mare serum gonadotropin (PMSG) injection and cultured in hCCCM (test group, n = 120) and DMEM + 20% FBS (control group, n = 120). The IVM rates and changes in perivitelline space (PVS) and shape were investigated at 8, 16, and 24 hr following the culture. The mature (MII) oocytes were subjected to in vitro fertilization (IVF) and the fertilization rate was assessed in three days. RESULTS: A significant difference was observed between the maturation rates in the hCCCM and control groups (24.16% vs 0%; p = 0.001), as well as morphologic changes between the two groups (p = 0.04, p = 0.05). The development rate for MII oocytes attained from IVM in the hCCCM group was 27.58% (2-cell) and 6.89% (4-cell). Data displayed that hCCCM is an effective medium for oocytes maturation compared to the control medium. CONCLUSION: hCCCM supports oocyte in vitro growth and maturation. Moreover, hCCCM changes the oocyte shape and size of perivitelline space.
