Fig. 4. Compound 7 in Bufadienolide glycosides and bufadienolides from the whole plants of Helleborus lividus, and their cytotoxic activity

Fig. 4. Compound 7 induced apoptosis in HL- 60 cells. A, Morphology of HL-60 cells treated with 7. HL- 60 cells were stained with DAPI after treatment with either 0.21 μM of 7 or 15 μM of etoposide for 15 h and then observed under a fluorescence microscope. B, Electrophoretic profile of the DNA of HL-60 cells treated with 7. HL-60 cells were incubated with either 0.21 μM of 7 or 15 μM of etoposide for 15 h. DNA was then extracted and analyzed by agarose gel electrophoresis. C, Caspase-3 activity in the lysates of HL-60 cells treated with 7. HL-60 cells were incubated with either 0.21 μM of 7 or 15 μM of etoposide for 12 h, and the caspase-3 activity in the lysates was measured using a caspase-3 colorimetric kit. The data are presented as the mean ± S.E.M. of three experiments. Results significantly different from that of the control group are indicated by * (p <0.001).