Juglanthraquinone C Induces Intracellular ROS Increase and Apoptosis by Activating the Akt/Foxo Signal Pathway in HCC Cells

Figure 6

JC induces apoptosis by increasing intracellular ROS. (a, c) Effect of JC on the total ROS levels in HepG2 and BEL-7402 cells was examined by flow cytometry. HepG2 cells were treated with DMSO or 8 μg/mL JC for 12, 24, 36, and 48 hours (a). BEL-7402 cells were treated with DMSO or 6.7, 8.7, and 10.5 μg/mL of JC for 12 hours (c). (b) Effect of JC on superoxide anion levels in HepG2 cells was examined by flow cytometry. The levels of ROS in HepG2 cells were treated with either DMSO or 8 μg/mL of JC for 12, 24, 36, and 48 hours and analyzed by flow cytometry. (d–f) Effects of JC on catalase and SOD2 expression and Akt activation were determined by Western blot analysis. HepG2 cells were treated with either DMSO or 8 μg/mL of JC for the indicated times (d and e). BEL-7402 cells were treated with DMSO or 8.7 μg/mL of JC for the indicated times (f). GAPDH was used as a loading control. (g–j) NAC and PEG-catalase abrogate JC-induced apoptosis. HepG2 cells were pretreated with NAC and PEG-catalase for 1 hour. HepG2 cells were treated with either DMSO or 8 μg/mL of JC for 36 hours and detected by Western blot analysis (g) or flow cytometry analysis (h). GAPDH was used as a loading control. BEL-7402 cells were treated with either DMSO or 8.7 μg/mL of JC for 24 hours and detected by flow cytometry analysis (i and j).

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