Fig. 3

Elevated production of mitochondrial ROS driven by NADPH oxidases. A Changes in MitoSOX™ fluorescence as measured using flow cytometry at the indicated time points (37 °C, 0, 2, 6, 12, and 24 h) after sublethal heat stress.B Superoxide production by NADPH oxidase was measured in total cell homogenates. C Heated or unheated HCC cells incubated with or without inhibitors of ROS: NAC(5 mM), MitoTEMPO (500 nM), DPI (10 μM), or VAS2870 (10 μM). Apoptosis was quantified using Annexin V-FITC/PI staining and flow cytometry at 24 h after sublethal heat stress. D ROS levels as measured by flow cytometry at 6 h after sublethal heat stress. E Heated or unheated HCC cells preincubated with or without inhibitors of NADPH oxidase: DPI (10 μM) and VAS2870 (10 μM), MitoSOX™ fluorescence as measured using flow cytometry at 6 h after sublethal heat stress. Values are the mean ± SE.**p < 0.01 vs. 37℃; ***p < 0.001 vs. 37℃; ###p < 0.001 vs. 6 h; ns no significance