Effect of melittin on nuclear morphology and caspase-3 activity in H
-treated SH-SY5Y cells. (A) Morphology of SH-SY5Y cells treated with H2O2 in the absence or presence of melittin for 6 h. Representative nuclear morphology was determined by a fluorescent DNA-binding agent DAPI staining and visualized by a fluorescence microscope (10×). (B) Melittin attenuated H2O2-induced increase in caspase-3 activity as determined using a caspase colormetric assay kit. (C) Melittin suppressed H2O2-induced expression of caspase-3 protein as determined by Western blot analysis. Data are expressed as mean ± SEM from three independent experiments. Bars with different letters indicate significant differences at p < 0.05.