Journal of Embryo Transfer 2013; 28(4): 361-371
Published online December 31, 2013
Copyright © The Korean Society of Animal Reproduction and Biotechnology.
Wang, Qing-Ling, Zhao, Ming-Hui, Jin, Yong-Xun, Kim, Nam-Hyung, Cui, Xiang-Shun
Department of Animal Sciences, Chungbuk National University, Chungbuk 361-763, South Korea.
The present study assessed the effect of FSH and LH on oocyte meiotic, cytoplasmic maturation and on the expression level and polyadenylation status of several maternal genes. Cumulus-oocyte complexes were cultured in the presence of FSH, LH, or the combination of FSH and LH. Significant cumulus expansion and nuclear maturation was observed upon exposure to FSH alone and to the combination of FSH and LH. The combination of FSH and LH during entire IVM increased the mRNA level of four maternal genes, C-mos, Cyclin B1, Gdf9 and Bmp15, at 28 h. Supplemented with FSH or LH significantly enhanced the polyadenylation of Gdf9 and Bmp15; and altered the expression level of Gdf9 and Bmp15. Following parthenogenesis, the exposure of oocytes to combination of FSH and LH during IVM significantly increased cleavage rate, blastocyst formation rate and total cell number, and decreased apoptosis. In addition, FSH and LH down-regulated the autophagy gene Atg6 and upregulated the apoptosis gene Bcl-xL at the mRNA level in blastocysts. These data suggest that the FSH and LH enhance meiotic and cytoplasmic maturation, possibly through the regulation of maternal gene expression and polyadenylation. Overall, we show here that FSH and LH inhibit apoptosis and autophagy and improve parthenogenetic embryo competence and development.
Keywords: apoptosis, autophagy, embryo development, maternal gene, oocyte maturation