黄芩苷对小鼠卵母细胞体外成熟的影响

Effects of Baicalin on in vitro maturation of oocytes in mouse

氧化应激是阻碍胚胎体外发育的重要因素之一,减少氧化应激可能是提高胚胎体外培养效果的途径。本文探讨了不同浓度黄芩苷对小鼠卵母细胞体外成熟及早期胚胎发育的影响,为体外抗氧化性研究及抗氧化物选择提供参考。试验选择4~6周龄雌性昆明小鼠获取GV期卵母细胞,在体外成熟培养液中分别添加不同浓度(0、20、40、60μmol/L)的黄芩苷,经37℃、5%CO_(2)、饱和湿度培养条件体外成熟12 h,统计卵母细胞第一极体排出率,检测卵母细胞胞质内活性氧(ROS)和还原型谷胱甘肽(GSH)含量以及培养液中谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性和总抗氧化能力(T-AOC),并采集8~10周龄雄性昆明小鼠精液,进行体外受精(IVF),分别于受精后6、24、96 h统计受精率、卵裂率和囊胚率。结果表明:体外成熟液中添加40、60μmol/L黄芩苷后,卵母细胞第一极体排出率较对照组显著提高(P<0.05),且浓度为40μmol/L极体排出率显著高于60μmol/L,但对成熟后的卵母细胞体外受精率、卵裂率、囊胚率无显著性影响(P>0.05),卵母细胞胞质ROS水平显著降低,GSH含量显著升高(P<0.05),培养液中GSH-Px、SOD、T-AOC含量显著高于对照组(P<0.05)。结论:成熟培养液中添加40μmol/L黄芩苷可以显著增强培养液中抗氧化酶活性,显著提高体外成熟小鼠卵母细胞抗氧化能力和第一极体排出率。

Oxidative stress is one of the important factors that block the development of embryos in vitro, and reducing oxidative stress is a way to improve the effect of embryo culture in vitro. In this paper, the effects of different concentrations of Baicalin on mouse oocyte maturation in vitro and early embryonic development were investigated, which would provide reference for the study of antioxidation in vitro and the selection of antioxidants. Different concentrations of Baicalin(0, 20, 40, 60 μmol/L) were added to the in vitro maturation(IVM) medium;and GV stage oocytes, obtained from female Kunming mice aged 4-6 weeks, were incubated in the IVM medium for 12 hours under the conditions of 37 ℃, 5% CO_(2)and saturated humidity. Then, the extrusion of the first polar body oocytes was counted, and the contents of reactive oxygen species(ROS) and glutathione(GSH) in the cytoplasm of the oocytes, glutathione peroxidase(GSH-Px), superoxide dismutase(SOD) enzyme activity and total antioxidant capacity(T-AOC) in the culture medium were determined. For in vitro fertilization, the semen collected from the 8-10-week-old male Kunming mice were mixed with the oocytes matured in vitro treated in Baicalin. Finally, the fertilization rate, cleavage rate and blastocyst rate were determined at 6, 24 and 96 h, respectively, after fertilization. The results showed that the extrusion rate of the first polar body of the oocytes treated in in 40, and 60 μmol/L Baicalin was significantly higher than that of the control group(P<0.05). Compare with the oocytes in the 60 μmol/L groups, the extrusion rate of the polar body of the oocytes in the 40 μmol/L groups was higher significantly. However, there was no significant effect on the in vitro fertilization rate, cleavage rate and blastocyst rate of mature oocytes between the each treatment(P>0.05), the level of ROS in the cytoplasm of the oocytes in the 40 μmol/L groups was dramatically decreased, but the content of GSH in the 40 μmol/L groups was increased(P<0.05), and the concentrations of GSH-Px, SOD and T-AOC in the culture medium of the 40 μmol/L Baicalin treatment was marked higher than that of the control group(P<0.05). In conclusion, adding 40 μmol/L Baicalin to the medium of mature oocytes in vitro significantly enhanced the activity of antioxidant enzymes, and significantly improved the antioxidant capacity and the extrusion of the first polar body of mouse oocytes matured in vitro.