Figure 4.

tBHQ reverses diosmetin (Dio)‐induced A549 and H1299 cells apoptosis and ROS production. (a) tBHQ (10 to 40 μM) increased Nrf2 activity (×10⁴) in a dose‐dependent manner in A549 and H1299 cells determined by ARE luciferase reporter assay. Data shown are means ± SD; n = 5. *P < 0.05, significantly different from control group. (b). tBHQ (20 μM) reversed diosmetin‐induced ROS accumulation. Data shown are means ± SD; n = 5. *P < 0.05, significantly different from control group; ^# P < 0.05, significantly different from Dio. (c) tBHQ (20 μM) blocked Dio (20 μM)‐induced apoptosis in A549 and H1299 cells. Data shown are means ± SD; n = 5. *P < 0.05, significantly different from control group; ^# P < 0.05, significantly different from Dio. (d) Nrf2 overexpression in A549 and H1299 cells analysed by Western blotting after 12‐hr incubation. Overexpression reversed diosmetin‐induced ROS accumulation (e). Data shown are means ± SD; n = 5. *P < 0.05, significantly different from control group. ^# P < 0.05, significantly different from Dio. (f) Overexpression of Nrf2 blocked Dio (20 μM)‐induced apoptosis in A549 and H1299 cells. Data shown are means ± SD; n = 5. *P < 0.05, significantly different from control group; ^# P < 0.05, significantly different from Dio. PI: propidium iodide