earticle

영어

The objective of this study was to investigate the effect of γ-tocotrienol (GTT; 50 μM) and/or L-ascorbic acid (Vc; 100 μM) under the oxidative stress condition (H2O2; 200 μM) on in vitro maturation and developmental competence in pigs. Porcine cumulus- oocyte complexes (COCs) were cultured in IVM medium containing GTT and/or Vc under the H2O2 condition for 44 h. After maturation, COCs were denuded and stained by orcein for evaluation of nucleic maturation. Intracellular reactive oxygen species (ROS) and glutathione (GSH) were respectively stained using carboxy-DCFDA and cell tracker red. Cleavage rate was determined in day 2 and day7, and blastocyst rate was determined in day 7 after in vitro fertilization. In results of nuclear maturation, oocytes in metaphase-Ⅰ (MI) were significantly higher in H2O2 treatment groups than GTT and/or Vc treatment groups (p<0.05). However, oocytes in MII stage were significantly increased in GTT treatment group than other treatment groups (p<0.05). Intracellular level of GSH was significantly increased by supplementation of GTT and/or Vc compared to control group (p<0.05). On the other hand, intracellular level of ROS was reduced in only GTT groups compared to other groups (p<0.05). In vitro development results showed that the cleavage rate of day 2, day 7 and blastocyst rate in GTT treatment group under the H2O2 condition were higher than other groups (p<0.05). Therefore, we suggest that treatment of GTT is effective on oocyte maturation and developmental competence rather than combined treatment of GTT and Vc in pigs.