Figure 4: BKFE inhibits ROS production in PA-treated SV40 MES13 cells. SV40 MES13 cells were pretreated with 20 μg/ml BKFE for 1 h and then treated with 100 μM PA for 5 h. (a) Intracellular ROS levels were determined using confocal microscopy on cells stained with the ROS-sensitive fluorescent dye DCFH-DA (original magnification, ×100). Relative fluorescence level was quantified using the ImageJ software. (b) ROS production in the cells was measured by flow cytometry with DCFH-DA. Values on the representative flow cytometry data indicate the DCF fluorescence intensity of whole cells. Relative levels of DCF fluorescence intensity were compared with ROS production in the control. p<0.01, and p<0.001.