Fig. 6.

Effects of 1,25(OH)₂D₃ on antioxidant capacity and cellular redox homeostasis. Expression of three oxidative stress related genes, (A) CAT, (B) SOD1, and (C) SOD2, in 6-hour cultures of BEAS-2B exposed to 100 µg/ml PM with or without 1,25(OH)₂D₃. In addition, after 24 h, the levels of (D) GSH, and (E) the ratio of oxidized to reduced NADP (NADP⁺/NADPH) in cells were measured. Data were mean ± SD of three independent experiments. ^***P < 0.001 and ^**P < 0.01 in comparison with untreated cells (control); ^###P < 0.05 and ^##P < 0.05 in comparison with PM-stimulated group