IGF-I对奶牛体外胚胎发育、ROS水平和IGF通路相关基因表达的影响

Effects of IGF-Ⅰon Development of in vitro Bovine Embryo, ROS Level and m RNA Transcripts Related to IGF Pathway

为了研究胰岛素样生长因子1(IGF-Ⅰ)对奶牛卵母细胞体外成熟和植入前胚胎发育的影响,在卵母细胞体外成熟(IVM)和胚胎体外培养(IVC)期间添加不同浓度(0、20、40、60、80 ng/m L)的IGF-Ⅰ。结果表明:与对照组相比,IVM培养液中添加60、80 ng/m L IGF-Ⅰ显著提高了卵母细胞的成熟率(75.8%、76.2%vs.62.1%);IVM和IVC培养液中添加60、80 ng/mL IGF-Ⅰ显著提高了卵裂率(59.2%、61.5%vs.40.2%)和囊胚率(28.1%、27.6%vs.18.3%)并显著降低了囊胚内ROS水平(55.2、57.1 vs.79.8)。与对照组相比,IVM和IVC培养液中添加40 ng/mL IGF-Ⅰ提高了囊胚IGFBP2基因的表达;IVM和IVC培养液中添加IGF-Ⅰ没有改变IGFBP3基因表达;IVM和IVC培养液中添加60、80 ng/mL IGF-Ⅰ提高了囊胚IGFBP6基因表达(0.36、0.39 vs.0.23)。结果提示,在IVM和IVC培养液中添加适量浓度的IGF-Ⅰ可降低胚胎内ROS水平,增加胚胎细胞内IGFBP6基因表达,提高胚胎的早期发育能力。

The objectives of this study were to examine the effects of insulin-like growth factor [ （IGF- I ） on the ooeytes maturation and early embryos development in cow. The different concentrations of IGF1 （0, 20, 40, 60 and 80 ng/mL） were added into the media during in vitro maturation （IVM） of oocytes and in vitro culture （IVC） of embryos. The results show that the addition of 60 or 80 ng/mL IGF- I to IVM media significantly increased the maturation rate （75.8%, 76.2% vs. 62.1%） in compare with the control group. The addition of 60 or 80 ng/mL IGF- I during IVM and IVC period significantly increased the cleavage rate （59.2%, 61.5% vs. 40.2%） and blastocyst rate （28.1%, 27.6% vs. 18.3%） compareing with the control group. The addition of 60 or 80 ng/mL IGF- I during IVM and IVC period significantly decreased the intraeellular ROS levels （55.2, 57.1 vs. 79.8） in blastocysts. Compared with the control group, addition of 40 ng/mL IGF- I to IVM and IVC media significantly increased the IGFBP2 gene expression levels （0.13 vs. 0.10） within 7 d blastocysts. The IGFBP3 gene expression was not significant difference when the different concentrations of IGF- I were added to IVM and IVC media. Addition of 60 or 80 ng/mL IGF- I to IVM and IVC media significantly increased the IGFBP6 gene expression levels （0.36, 0.39 vs. 0.23） within 7 d blastocysts. These results indicate that addition of appropriate concentration of IGF- I during IVM and IVC period can improve the ability of early embryonic development by alleviating oxidative stress and adding IGFBP6 gene expression.