目的 研究虎皮楠生物碱daphnioldhanin E诱导人肝癌HepG2细胞死亡的机制。方法 HepG2细胞用daphnioldhanin E（10、30 μg/mL）处理后，瑞姬氏染色法观察细胞形态变化，DNA琼脂糖凝胶电泳检测细胞凋亡情况，MTT法检测细胞凋亡抑制剂Z-VAD- FMK对daphnioldhanin E抗癌活性的影响，分光光度法检测caspase-3酶活性的变化。结果 瑞姬氏染色显示，HepG2细胞经daphnioldhanin E处理48 h后，细胞体积增大，细胞核清晰可见，周围出现大量的胞浆空泡，但细胞膜仍保持完整；DNA琼脂糖凝胶电泳结果可见大量50～200 bp的片段；MTT法检测结果显示Z-VAD-FMK不能阻断daphnioldhanin E对HepG2细胞增殖的抑制作用；分光光度法测定显示，daphnioldhanin E给药组与对照组HepG2细胞caspase-3酶活性无明显变化，表明daphnioldhanin E对HepG2细胞的杀伤作用与caspase-3激活通路无关。结论 Daphnioldhanin E可能通过类凋亡方式明显诱导HepG2细胞程序性死亡，该过程不依赖于caspase-3途径。

Objective To investigate the mechanism of HepG2 cell death induced by daphnioldhanin E from Daphniphyllum oldhami. Methods The HepG2 cells were treated with daphnioldhanin E (10 and 30 μg/mL), and the morphologic changes of cells were observed by Wright-Giemsa staining. DNA agarose gel electrophoresis, MTT assay, and spectrophotometric method were conducted to detect cell apoptosis, effect of Z-VAD-FMK on antitcancer activity of daphnioldhanin E, and activity changes of caspase-3, respectively. Results Wright-Giemsa staining demonstrated that the volume of HepG2 cell increased after 48 h treatment with daphnioldhanin E, the nucleus was clearly visible and surrounded by a large number of cytoplasmic vacuoles, while the cell membranes remained intact. DNA ladder electrophoresis resulted in a large number of small fragments of 50—200 bp; MTT assay displayed that Z-VAD-FMK could not block the inhibition of daphnioldhanin E on the proliferation of HepG2 cells; Spectrophotometric results demonstrated that caspase-3 activity of HepG2 cells had no obvious change compared with the control group, which indicated that the lethal effect of daphnioldhanin E on HepG2 cells was unrelated to caspase-3 activation pathway. Conclusion Daphnioldhanin E could induce the programmed death of HepG2 cells by paraptosis and the process is not dependent on the caspase-3 pathway.