ABSTRACT: Two pigmented compounds from Uroleucon nigrotuberculatum, uroleuconaphin-B(1) [corrected] (H427) and uroleuconaphin-A(1) [corrected] (H373), significantly diminished the cell viability of HL60 cells with IC50 of 10 microM and 30 microM, respectively, in an 18 h-dye uptake assay. Both H427 and H373 augmented the levels of intracellular reactive oxygen species (ROS) and induced apoptosis as demonstrated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling analysis. ROS augmentation by both H427 and H373 was inhibited by N-acetylcysteine (NAC) and alpha-tocopherol. The apoptosis induced by H427 was inhibited efficiently with NAC and caspase-8 inhibitor but less efficiently with alpha-tocopherol and caspase-9 inhibitor. These findings suggested that these pigments have pro-apoptotic activities via oxidative stress.
Biological & Pharmaceutical Bulletin 01/2007; 29(12):2383-7. · 1.66 Impact Factor