(A and B) The ROS production of A549 (A) or CaLu-3 (B) cells pretreated with 100, 200, or 500 ng/ml hCypA for 2 h, and then treated with H₂O₂ (200 μM) for 24 h. (C) Analysis of MDA generation of A549 cells pretreated with 100, 200, or 500 ng/ml hCypA for 2 h, and then treated with H₂O₂ (200 μM) for 24 h. (D) The levels of SOD in A549 cells pretreated with 100, 200, or 500 ng/ml hCypA for 2 h, and then treated with H₂O₂ (200 μM) for 24 h. (E and F) Intracellular GSH-Px (E), GSH (F) activities in A549 cells pretreated with 100, 200, or 500 ng/ml hCypA for 2 h, and then treated with H₂O₂ (200 μM) for 24 h. (G) Intracellular GSH activities in A549 cells pretreated with 100, 200, or 500 ng/ml hCypA for 2 h, and then treated with BSO (50 μM) for 24 h. Data information: The data are shown as the means ± SD (A–G: n=3). *P<0.05 and **P<0.01 (unpaired two-tailed Student’s t-test). The data are representative of at least three independent experiments.