BACKGROUND: All-trans retinol is a biological antioxidant
scavenging the ROS in the cell culture. OBJECTIVES: This study
was conducted to investigate the effect of all-trans retinol in
fertilization and culture medium on mouse embryo's developmental
competence. METHODS: 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 μM). 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 μM) for 5 days to the blastocyst stage. RESULTS: In the
first experiment, the blastocyst formation rate significantly
increased by 5 μM 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 μM all-trans retinol than
those in the presence of 0 and 1 μM 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 μM all-trans retinol
than that of the control group. CONCLUSIONS: These results
showed that supplementation of fertilization medium with 5 μM 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.