Wang Dong-Hui, Zhou Hong-Xia, Liu Shu-Jun, Zhou Cheng-Jie, Kong Xiang-Wei, Han Zhe, Liang Cheng-Guang
State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, The Research Center for Laboratory Animal Science, College of Life Science, Inner Mongolia University, Hohhot, Inner Mongolia, People's Republic of China.
State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, The Research Center for Laboratory Animal Science, College of Life Science, Inner Mongolia University, Hohhot, Inner Mongolia, People's Republic of China.
Theriogenology. 2018 Jun;113:92-101. doi: 10.1016/j.theriogenology.2018.02.015. Epub 2018 Feb 19.
Paracrine factors such as glial cell line-derived neurotrophic factor (GDNF), which was originally derived from the supernatants of a rat glioma cell line, play pivotal roles in oocyte maturation and early embryo development in mammals, such as mice, rats, pigs, sheep, and even humans. However, whether GDNF facilitates in vitro oocyte maturation or early embryo development in bovines is not yet known. We show for the first time that GDNF and its receptor, GDNF family receptor alpha-1 (GFRA1), are presented in ovarian follicles at different stages as well as during oocyte maturation and early embryo development. Immunostaining results revealed the subcellular localizations of GDNF and GFRA1 in oocytes throughout follicle development, first in germinal vesicles and during blastocyst embryo stages. The ability of exogenously applied GDNF to promote oocyte maturation and early embryo development was evaluated in culture, where we found that an optimal concentration of 50 ng/mL promotes the maturation of cumulus-oocyte complexes and the nuclei of denuded oocytes as well as the development of embryos after IVF. To further investigate the potential mechanism by which GDNF promotes oocyte maturation, bovine oocytes were treated with morpholinos targeting Gfra1. The suppression of GFRA1 presence blocked endogenous and exogenous GDNF functions, indicating that the effects of GDNF that are essential and beneficial for bovine oocyte maturation and early embryo development occur through this receptor. Furthermore, we show that supplementation with GDNF improves the efficiency of bovine IVF embryo production.
旁分泌因子，如最初从大鼠胶质瘤细胞系的上清液中提取的胶质细胞源性神经营养因子（GDNF），在哺乳动物（如小鼠、大鼠、猪、绵羊甚至人类）的卵母细胞成熟和早期胚胎发育中发挥着关键作用。然而，GDNF是否促进牛的体外卵母细胞成熟或早期胚胎发育尚不清楚。我们首次表明，GDNF及其受体胶质细胞源性神经营养因子家族受体α-1（GFRA1）在不同阶段的卵巢卵泡以及卵母细胞成熟和早期胚胎发育过程中均有表达。免疫染色结果揭示了GDNF和GFRA1在卵泡发育全过程中在卵母细胞中的亚细胞定位，首先是在生发泡期以及囊胚期胚胎阶段。在培养中评估了外源性应用GDNF促进卵母细胞成熟和早期胚胎发育的能力，我们发现最佳浓度为50 ng/mL时可促进卵丘-卵母细胞复合体和裸卵细胞核的成熟以及体外受精后胚胎的发育。为了进一步研究GDNF促进卵母细胞成熟的潜在机制，用靶向Gfra1的吗啉代寡核苷酸处理牛卵母细胞。GFRA1表达的抑制阻断了内源性和外源性GDNF的功能，表明GDNF对牛卵母细胞成熟和早期胚胎发育至关重要且有益的作用是通过该受体实现的。此外，我们表明补充GDNF可提高牛体外受精胚胎生产的效率。
