RÉSUMÉ
Objective To observe the effects of serum containing Jinghou Zengzhi Recipe (JHZZ) on the expression of growth differentiation factor 9 (GDF9) and Bim in cumulus-oocyte complexes (COCs) and cumulus cells (CCs) of controlled ovarian hyperstimulation (COH) rats,and to investigate its curative effect and mechanism.Methods The rat COH ovarian model was prepared for collecting COCs and CCs,which were respectively co-cultured in vitro with the blank serum of female COH SD rat and serum containing JHZZ,and the each group was divided into 3 subgroups:the blank serum group (blank group),serum containing JHZZ group (control group) and serum containing JHZZ plus GDF9 receptor blocker group (experimental group),total 6 subgroups.COCs and CCs were collected after 24 h.The expression levels of GDF9 and Bim mRNA were detected by real-time quantitative PCR.The GDF9 protein expression levels were detected by Western blot.Results (1) The expression level of GDF9 mRNA in control group COCs was obviously higher than that in the control group and experiment group COCs (P＜0.05);the Bim mRNA expression level in COCs of control group and experiment group was significantly lower than that in COCs of blank group (P＜ 0.05);the GDF9 protein expression level in the control group COCs was significantly higher than that in the blank group COCs (P＜0.05),and also higher than that in the experiment group COCs,but the difference was not statistically significant (P＞0.05).(2)The comparison results of GDF9 mRNA expression level in CCs among 3 groups were consistent with those in COCs;the Bim mRNA expression level in CCs of control group and experimental group was significantly lower than that in the blank group (P＜ 0.05);the Bim mRNA expression level in the control group CCs was significantly lower than that in the experimental group CCs (P＜0.05);the GDF9 protein expression level in the control group CCs was significantly higher than that in the blank group and experimental group CCs (P＜0.05).(3)The GDF9 mRNA expression level in the control group COCs was significantly higher than that in CCs (P＜0.05),and the other inter-group comparisons between COSs and CCs had no statistical difference (P＞0.05).Conclusion Serum containing JHZZ can increase the GDF9 expression level in COCs and CCs,maintain the low expression of Bim in COCs and CCs,inhibit the ovarian cells apoptosis and promote the follicular development;COCs is more conducive to the expression of GDF9 mRNA compared with CCs eliminating oocyte.
RÉSUMÉ
The success of in vitro embryo production (IVEP) in animals has improved over time, employing a variety of culture media. Here, we assessed the maturation timing and developmental potential of sheep oocytes in vitro at different concentrations of fetal bovine serum (FBS). Cumulus oocyte complexes (COCs) were aspirated from follicles (2-6 mm) of sheep ovaries collected from local slaughter house. COCs were randomly divided into two groups and matured at 38.5°C, 5% CO2 for 24 h (Group I) and 27 h (Group II). Oocytes cultured for 27 h showed significantly (P <0.05) more maturation than those cultured for 24 h (82 vs. 76%) followed by more cleavage (35 vs. 30%), morula (53 vs. 39%) and blastocyst (17 vs. 11%) percentage. In the second experiment, oocytes were randomly divided into two groups and matured with 10% FBS (Group I) and 20% FBS (Group II) for 27 h supplemented with pyruvate, glutamine, LH, FSH and estradiol. After maturation, oocytes were fertilized by fresh semen for 18 h. Presumptive zygotes in both the groups were again divided into two groups and cultured in 10 and 20% FBS during post fertilization period, respectively. Different FBS concentration in maturation medium did not influence maturation percentage (82 vs. 79%) significantly. Out of culture groups, presumptive zygotes matured in 20% FBS and cultured in 20% FBS during post fertilization period showed significant increase in cleavage percentage (44 vs. 39, 35 and 27%) as compared to other groups but subsequent development to morula (55 vs. 53, 43 and 40%) and blastocyst (20 vs. 17, 16 and 15%) percentage were more in the group matured in 10% FBS and cultured in 20% FBS during post fertilization period.