earticle

영어

Alpha-linolenic acid (ALA) is one of n-3 polyunsaturated fatty acids and found mainly in the chloroplasts. Many studies have been reported that when intracellular reactive oxygen species (ROS) in mammalian oocytes was reduced by supplementation of ALA in in vitro maturation (IVM) medium. Based on these reports, we expected that ALA acts as an antioxidant during IVM of porcine oocytes. Therefore, the objective of this study was to investigate the antioxidant effect of ALA supplementation during IVM in porcine oocytes. The cumulus-oocyte complexes (COCs) were incubated in IVM medium containing 200 μM H2O2 or H2O2 with 50 μM ALA for 44 h. Nuclear maturation stage of oocytes was evaluated using aceto-orcein method. For measurement of oxidative stress status, intracellular ROS and glutathione (GSH) levels were measured using carboxy-DCFDA and cell tracker red, respectively. In results, oocytes in metaphase-II stage were reduced by H2O2 treatment (control: 80.00%; H2O2 grop: 61.84%) and it was slightly recovered by treatment of ALA (69.76%) (p<0.05). The intracellular GSH levels decreased in H2O2 groups compared with control groups, but it was enhanced by ALA treatment (p<0.05). On the contrary, H2O2 treatment increased intracellular ROS level in oocytes and H2O2 induced ROS was decreased by treatment of ALA (p<0.05). Our findings shown that ALA treatment under oxidative stress environment recovered oocyte maturation via increase of GSH and decrease of ROS in oocytes. Therefore, these results suggest that ALA have an antioxidative ability and it could be used as antioxidant in in vitro production system of porcine embryo.