Figure 2.
Se supplementation restores antioxidant activity in UV-irradiated mouse melanocytes. (a) Treatment with sodium selenite for 24 h increases GPx activity in un-irradiated cells by more than 4.6-fold compared to those grown in basal medium, n = 3 for each point. (b) UV radiation (1000 J/m2) severely depletes GPx activity in irradiated melanocytes 24 h after irradiation, but pre-treatment with 500 nM sodium selenite restores enzyme activity to that of controls (* p ≤ 0.008), n = 3 for each condition. (c) Melanocytes irradiated with UV (1000 J/ m2) had significantly reduced levels of glutathione at 24 and 48 h after irradiation. Glutathione in cells pre-treated for 24 h with 500 nM sodium selenite was higher in irradiated cells at 24 h post-irradiation, and was restored to levels of untreated controls after 48 h (* p < 0.01; ** p = 0.023).