Abstract：
The in vitro maturation (IVM) quality of oocytes is directly related to the subsequent developmental potential of embryos and a fundamental of in vitro embryo production. However, conventional IVM methods fail to maintain the gap-junction intercellular communication (GJIC) between cumulus-oocyte complexes (COCs), which leads to insufficient oocyte maturation. Herein, we investigated the effects of three different three-dimensional (3D) culture methods on oocyte development in vitro, optimized of the alginate-hydrogel embedding method, and assessed the effects of the alginate-hydrogel embedding method on subsequent embryonic developmental potential of oocytes after IVM and parthenogenetic activation (PA). The results showed that Matrigel embedding and alginate-hydrogel embedding benefited the embryonic developmental potential of oocytes after IVM and PA. With the further optimization of alginate-hydrogel embedding, including crosslinking and decrosslinking of parameters, we established a 3D culture system that can significantly increase oocyte maturation and the blastocyst rate of embryos after PA (27.2 ± 1.5 vs 36.7 ± 2.8, P < 0.05). This 3D culture system produced oocytes with markedly increased mitochondrial intensity and membrane potential, which reduced the abnormalities of spindle formation and cortical granule distribution. The alginate-hydrogel embedding system can also remarkably enhance the GJIC between COCs. In summary, based on alginate-hydrogel embedding, we established a 3D culture system that can improve the IVM quality of porcine oocytes, possibly by enhancing GJIC.
摘要：
卵母细胞的体外成熟（IVM）质量直接关系到胚胎的后续发育潜力和体外胚胎产生的根本。然而,传统的IVM方法无法维持卵丘-卵母细胞复合物（COCs）之间的间隙连接细胞间通讯（GJIC），导致卵母细胞不成熟。在这里，我们研究了三种不同的三维（3D）培养方法对体外卵母细胞发育的影响，优化了海藻酸盐-水凝胶包埋方法，并评估了海藻酸盐-水凝胶包埋方法对IVM和孤雌生殖激活（PA）后卵母细胞的后续胚胎发育潜力的影响。结果表明，基质胶包埋和藻酸盐-水凝胶包埋有利于IVM和PA后卵母细胞的胚胎发育潜能。随着海藻酸凝胶包埋工艺的进一步优化,包括参数的交联和去交联，我们建立了3D培养系统，可以显着提高PA后卵母细胞的成熟度和胚胎的囊胚率（27.2±1.5vs36.7±2.8，P<0.05）。这种3D培养系统产生的卵母细胞线粒体强度和膜电位显着增加，减少了纺锤体形成和皮质颗粒分布的异常。藻酸盐-水凝胶包埋系统还可以显着增强COC之间的GJIC。总之,基于藻酸盐-水凝胶包埋，建立了能够提高猪卵母细胞IVM质量的三维培养系统,可能是通过增强GJIC。
