ABSTRACT
All-trans retinol is a biological antioxidant scavenging the ROS in the cell culture. This study was conducted to investigate the effect of all-trans retinol in fertilization and culture medium on mouse embryo's developmental competence. This study was designed into two experiments. In the first experiment, in vitro mature oocytes were co-cultured with sperm in fertilization medium containing different concentrations of all-trans retinol [0, 1, 5, and 10 micro M]. After fertilization, zygotes in each group were separately cultured in CZB culture medium for 5 days to the blastocyst stage. In the second experiment, in vitro produced zygotes were cultured in CZB culture medium containing different concentrations of all-trans retinol [0, 1, 5, and 10 micro M] for 5 days to the blastocyst stage. In the first experiment, the blastocyst formation rate significantly increased by 5 micro M in all-trans retinol, which was more than those of the other groups. Also, percentage of grade one embryos was significantly higher in the presence of 5 micro M all-trans retinol than those in the presence of 0 and 1 micro M all-trans retinol. In the second experiment, different concentrations of all-trans retinol could not alter blastocyst formation rate; however, the percentage of grade one embryo was higher in the presence of 10 micro M all-trans retinol than that of the control group. These results showed that supplementation of fertilization medium with 5 micro M alltrans retinol could improve mouse embryo's development and morphology. On the other hand, supplementation of embryo culture medium can improve mouse embryo morphology without any effect on embryo developmental competence