N-(2-mercaptopropionyl)-glycine enhances in vitro pig embryo production and reduces oxidative stress

This study evaluated the effects of different concentrations (1, 10, 25, 50, and 100 mu M) of the antioxidant N-(2-mercaptopropionyl)-glycine (NMPG), during the culture of in vitro-fertilized porcine oocytes. While the highest concentrations of NMPG (50 and 100 mu M) were toxic to the developing embryos during the first two days of culture, 25 mu M NMPG achieved cleavage rates that were similar to those achieved by the control but did not sustain blastocyst production by Day 7 of culture. Compared to the control culture medium, the culture medium supplemented with 10 mu M NMPG increased (P<0.05) the rates of blastocyst formation, decreased (P<0.05) the intracellular levels of reactive oxygen substances, and downregulated (P<0.05) the expression of the oxidative stress related gene GPX1. In conclusion, these results demonstrated that supplementation of porcine embryo culture medium with 10 <mu>M NMPG can attenuate oxidative stress and increase the yield of in vitro production of blastocysts.