The effect of all-trans retinol on in vitro mouse embryo's developmental competence

Abstract

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