Reproduction Abstracts

The carboxyethylgermaniumsesquioxide (Ge-132) is an organogermanium compound known to have anti-oxidative effect. In this study, we examined the effect of Ge-132 on in vitro maturation (IVM) of porcine oocytes analyzing intracellular glutathione (GSH) and reactive oxygen species (ROS) levels, mRNA expression levels and subsequent embryonic development after in vitro fertilization (IVF) and parthenogenetic activation (PA). After 40 h of IVM, intracellular GSH levels in oocytes treated with 200 μg/ml Ge-132 increased significantly (P<0.05) and the 200- and 400 μg/ml Ge-132 treated groups showed a significant (P<0.05) decrease in intracellular ROS levels compared with the control. Oocytes matured with 200 μg/ml Ge-132 during IVM had higher total cell numbers after IVF than the control group. Furthermore, oocytes matured with 200- and 400 μg/ml Ge-132 during IVM had significantly higher cleavage rates and the 200 μg/ml Ge-132 treated group had higher blastocyst formation rates and total cell numbers after PA than the control group. We evaluated mRNA expression levels of PCNA and Nrf-2 in the cumulus cells of each group. The 100- and 400 μg/ml Ge-132 group showed significantly higher mRNA expression levels of PCNA (P<0.05) and Nrf-2 (P=0.062) respectively compared to those of the control group. Our results suggested that Ge-132 treatment during IVM improved the developmental potential of PA and IVF porcine embryos by decreasing the intracellular GSH level, there by increasing the intracellular ROS level and regulating gene expression of cumulus cells during oocyte maturation.

This work was supported, in part, by a grant from the National Research Foundation of Korea Grant Government (NRF-2012R1A1A4A01004885, NRF-2013R1A2A2A04008751), Republic of Korea.