Figure 3. Lack of effect of SERPINA3K on the intracellular ROS generation in cells exposed to H₂O₂.

(A, B) The rMC-1 cells were treated with 400 µM H₂O₂ (A) or 20 µM TBHP (B) for 1, 2, 4 and 8 h in the absence or presence of 1 µM BSA or SERPINA3K. Viable cells were quantified using MTT assay (mean±SEM, n = 3). (C) The rMC-1 cells were exposed to 400 µM H₂O₂ or 20 µM TBHP for various durations as indicated, to define the time point for the ROS increase. Note that ROS levels were elevated by H₂O₂ as early as 15 min, while the ROS generation induced by TBHP occurred at 4 h of the treatment. (D&E) rMC-1 cells were pre-treated with various concentrations of SERPINA3K for 1 h. The medium was supplemented with BSA to the same total protein concentration in each well. The cells were then exposed to 400 µM H₂O₂ for 15 min (D) or to 20 µM TBHP for 4 h (E). The intracellular ROS generation was measured using CM-H2DCFDA as a probe. Values are arbitrary fluorescence units (mean±SEM, n = 8). SERPINA3K blocked the ROS increase induced by TBHP but not that by H₂O₂. * P<0.01, the SERPINA3K-treated cells versus the BSA-treated cells. & P<0.01, the BSA-treated cells exposed to H₂O₂ versus the BSA-treated cells without H₂O₂ exposure. # P<0.05, the H₂O₂ or TBHP-treated cells versus control cells.