目的：观察来源于海芒果种子的皂苷类化合物nerifolin对人肝癌细胞HepG2增殖及凋亡的影响，初步探讨其作用机制。方法：MTT法检测不同质量浓度nerifolin对HepG2细胞增殖的影响，流式细胞术检测nerifolin对HepG2细胞周期和凋亡的影响。Caspase试剂盒检测nerifolin对HepG2细胞caspase-3酶活化的影响。结果：Nerifolin可时间和剂量依赖性地抑制HepG2细胞增殖，作用24、48、72 h的IC50分别为（2.34±0.08）、（0.13±0.01）、(0.06±0.01) μg/ml。随着nerifolin(0.1 μg/ml)作用时间的延长，HepG2细胞S期百分比逐渐增多，而G0/G1期百分比逐渐减少（P<0.01），nerifolin阻滞HepG2细胞于S期。Nerifolin作用后，HepG2细胞早期凋亡率上升至22.65%，caspase-3活性比对照组明显升高（P<0.01）。结论：Nerifolin可通过S期阻滞抑制HepG2细胞的增殖，通过caspase-3依赖途径诱导HepG2细胞的凋亡。

Objective:To investigate the effects of nerifolin, an isolate from the seeds of Cerbera manghas L., on the proliferation and apoptosis of human hepatocellular carcinoma cell line HepG2 and the related mechanism. Methods: Effect of nerifolin on the proliferation of HepG2 cells was examined by MTT assay, and its effects on cell cycle and apoptosis of HepG2 cells were assessed by flow cytometry. Effect of nerifolin on caspase-3 activation in HepG2 cells was examined by caspase detecting kit. Results: Nerifolin inhibited the proliferation of HepG2 cells in a dose- and time-dependent manner, with the IC50 values being (2.34±0.08), (0.13±0.01) and (0.06±0.01) μg/ml after nerifolin treatment for 24, 48, and 72 h, respectively. The proportion of HepG2 cells in S phase increased with the prolongation of nerifolin treatment, and the proportion in G0/G1 phase gradually decreased (P<0.05), indicating that nerifolin blocked HepG2 cells in S phase. Early apoptosis rate of HepG2 cells increased to 22.65%, and caspase-3 activity was significantly increased after nerifolin treatment (P<0.01). Conclusion: Nerifolin can inhibit the proliferation of HepG2 cells by inducing S phase arrest and can trigger apoptosis via caspase-3 dependent pathway.

国家高科技研究发展计划（863计划）项目资助（No. 2006AAD9Z447）