Addition of beta-mercaptoethanol or Trolox (R) at the morula/blastocyst stage improves the quality of bovine blastocysts and prevents induction of apoptosis and degeneration by prooxidant agents

作者：Feugang JM; De Roover R; Moens A; Leonard S; Dessy F; Donnay I^*

来源：Theriogenology, 2004, 61(1): 71-90.

DOI：10.1016/S0093-691X(03)00191-2

• antioxidants
• apoptosis
• cattle
• embryo culture
• oxidative stress

This study was conducted to evaluate the effect of beta-mercaptoethanol (a stimulator of glutathione synthesis) and Trolox(R) (an hydrosoluble analogue of Vitamin E) on bovine embryos cultured from the morula stage (Day 5 post-insemination; pi) under oxidative stress conditions. Culture of embryos with increased doses of Trolox(R) showed a dose-dependent embryotoxicity on Day 8 pi. The use of 400 muM Trolox(R) as well as beta-mercaptoethanol at 100 muM prevented at least partly (P < 0.05) the prooxidant-induced blastocyst degeneration on Day 8. Hatching rates of surviving blastocysts were significantly increased by both antioxidants and β-mercaptoethanol alone improved their mean cell numbers, which was significant in the ICM (P < 0.05). Analysis of their effect on Day 7 pi showed that both the antioxidants significantly reduced the prooxidant-induced apoptosis and beta-mercaptoethanol diminished the physiological level of apoptosis as well as it stimulated the glutathione synthesis (P < 0.05). In addition, a comparison between in vitro- and in vivo-produced embryos showed that the levels of apoptosis were similar at the same age post-insemination (morulae and blastocysts) but increased steadily with the embryonic age in in vitro ones.
In conclusion, β-mercaptoethanol and Trolox(R) added separately from the morula stage protected embryos against oxidative stress and improved the quality of the resulting blastocysts.

• 出版日期2004-1-1