PSIV-B-41 Late-Breaking: The effect of TP, ALC and NAC cocktail on the oxidation-reduction system of mouse early embryo during in vitro culture

Abstract During in vitro culture, the growth environment of embryos cannot be completely simulated as an in vivo, because the embryos are exposed to oxidative stress (OS) for a long time. However, the supplementation of antioxidants to the culture medium is undoubtedly the most effective method to reduce OS. Previous Studies have shown that TP, ALC and NAC alone have antioxidant effects on OS embryos during different stages of the oxidation-reduction reaction system respectively. Therefore in the current study we used TP, ALC and NAC in combination to improve the quality of early mice embryo and its effects on the embryo endogenous oxidation-reduction reaction system, to minimize the obstacles in the process of in vitro embryo during oxidative stress. The expression of endogenous genes in embryos was detected by RT-PCR, and the ROS and GSH levels in embryos were determined by DCHFDA and CMF2HC staining respectively. The combine supplementation of TP, ALC and NAC significantly up-regulate the expression of oxidase genes (NOX1, NOX2, NOX4, Duox1 and Duox2) in embryo, and effectively promote the expression of antioxidant enzymes genes (SOD1,SOD2,CAT, GPx1,GPx2 and GPx4) in the embryo. In addition, the supplementation of TP, ALC and NAC also up-regulated the expression of Nrf2 gene in embryo (P ﹤ 0.01）as compare to other groups. Moreover the addition of TP, ALC and NAC to embryo culture medium significantly decreased the ROS level (P ﹤ 0.01）and increased the GSH level (P ﹤ 0.01）as compare to control and other treated groups. In conclusion the present study shows that the supplementation of TP, ALC and NAC cocktail can promote the early mouse embryo development, effectively upregulate GSH and down-regulate the ROS level in early mouse embryo during IVC. Moreover it up-regulate the expression of oxidase and antioxidant enzymes and Nrf2 genes.