Figure 6.

Induction of apoptosis by Compound A is dependent on the production of reactive oxygen species. (A) G361 cells were pre-treated with H₂DCFDA and treated with Compound A and curcumin with or without the antioxidant N-Acetyl-L-cysteine (NAC) for 3 h, as described in the materials and methods section. Production of ROS was evaluated through image-based cytometry with the y-axis indicative of the percent of DCF positive cells. *p < 0.05 vs. DCF [+] cells of DMSO control; #p < 0.05 vs. DCF [+] cells of groups treated without NAC. (B) G361 cells were treated with the Compound A and curcumin with or without NAC for 48 h. Subsequently, cells were stained with Annexin V and PI, as described in the materials and methods. Image based cytometry was utilized to assess apoptosis. The y-axis represents the percent of cells positive for Annexin V (green), PI (red), Annexin V and PI (yellow), or negative for both Annexin V and PI (blue). All graphical values are expressed as a mean ± SD from three independent experiments. Doxorubicin (DOX) was used as a positive control. *p < 0.05 vs. DMSO control (comparison of viable cells only); #p < 0.05 vs. groups treated without NAC (comparison of viable cells only). PQ = Paraquat, A = Compound A, CUR = Curcumin.