N800425

The alveolar epithelial cells A549 (Dingguo Changsheng) were cultured in RPMI 1640 medium (HyClone) supplemented with 10% foetal bovine serum (Clark) and 1% penicillin/streptomycin in 25 cm² culture flask at 37°C in 5% CO₂. A549 cells were treated by MA with the dosage of 0.1, 0.5, 1 and 5 mmol/L for 6, 12 and 24 hours.24 A549 cells were preincubated with N‐acetylcysteine (NAC; N800425, Macklin) or Resveratrol (Res; R817263, Macklin) dissolved in dimethyl sulfoxide (DMSO; D5879, Sigma) for 1 hour before 5 mmol/L MA stimulation. The concentration of DMSO in the medium never exceeded 0.1% to avoid its toxicity towards the A549 cells. To evaluate the effects of NAC, the cells were divided into control group, 5 mmol/L MA group, 5 mmol/L NAC group, and 5 mmol/L MA plus 5 mmol/L NAC group.25 To evaluate the effects of Res, the cells were divided into control group, 5 mmol/L MA group, 20 μmol/L Res group and three MA plus Res (1, 5, 20 μmol/L) groups.26

The human lung fibroblast IMR90 cells were a gift from Dr. Xudong Zhao (Sichuan University West China Medical School) and obtained from the American Type Culture Collection (ATCC; CCL-186). The cells were grown in MEM with 1% sodium pyruvate, 1% penicillin-streptomycin, and 10% fetal bovine serum (Gibco, A3161001C) in a humidified, 5% CO₂:95% air incubator at 37 °C. When attained 50 PD, IMR90 cells were treated with 500 μM of α-KB (MACKLIN, C10962521), 5 mM NAC (MACKLIN, N800425), or 10 mM 3-Methyladenine (MACKLIN, 5142-23-4). ddH2O or DMSO was used as a control.