earticle

영어

Amino acids have been regarded as beneficial for the development of preimplantation embryos and acted critically in the in vitro culture of porcine embryos. However, some reviews of emerging literatures show that supplementation of essential amino acids (EAAs) to in vitro culture medium was improved less than usually expected. The present study was designed to investigate the effects of EAAs on the in vitro development of porcine preimplantation embryos after parthenogenetic activation. The results showed that supplementation of EAAs to porcine zygote medium-3 (PZM-3) with 1:50 significantly decreased the blastocyst rate of parthenogenetic embryos (12.8±4.0 vs. 25.6±4.2) although cleavage rate was not different (p<0.05). On the other hand, the distribution pattern of total cell number of the blastocysts varied widely while the average number has not shown significant difference. Real-time qPCR analysis revealed that EAAs have turned over transcription pattern of imprinted genes: the relative abundance of H19 transcript was enhanced and level of IGF2r transcript was decreased significantly (p<0.05). Interestingly, gene expression of mTOR, activated by some essential amino acids, was significantly up-regulated (p<0.05). In conclusion, these results indicate that the presence of essential amino acids in the in vitro culture medium might impair embryo development due to mRNA turnover of imprinted genes, but could possibly play an important role at the implantation stage because development of protrusive trophoblast activity requires some amino acids-dependent mTOR signaling in early blastocysts.