金荞麦Fr4诱导HL-60细胞凋亡及对端粒酶活性的影响

目的研究金荞麦有效部位Fr4能否诱导HL-60细胞凋亡及对端粒酶活性的影响。方法用MTT法检测Fr4对细胞增殖的影响;光学显微镜和透射电镜观察细胞形态改变;Annexin-V/PI双染法检测细胞膜介导的凋亡;琼脂糖凝胶电泳观察DNA碎片;TRAP-PCR-ELISA检测端粒酶活性。结果金荞麦Fr4 60~240 mg.L-1能诱导HL-60细胞凋亡,电镜观察到典型的凋亡细胞,电泳呈现出阶梯状条带,流式细胞仪检测到早期凋亡细胞数随剂量的增加而升高。MTT法示金荞麦Fr4抑制HL-60细胞增殖,并且呈剂量依赖性趋势,药物作用24 h的IC50为115 mg.L-1,Fr4诱导HL-60细胞凋亡过程中,端粒酶活性下降。结论金荞麦Fr4可诱导HL-60细胞凋亡,其机制可能与端粒酶活力下降有关。

Induction of apoptosis and inhibition of telomerase activity by extract of Fagopynum cymosum(Fr4) in human leukemia HL-60 cells

Aim To study effect of the extract of Fagopynum cymosum(Fr4) on the apoptosis and telomeraseactivity in human leukemia HL-60 cells.Methods HL-60 cells were treated with Fr4 and inhibition of proliferation was measured with MTT assay.Cell morphology before and after the treatment was examined with light and electron microscopy.FILC-Annexin-V and PI double staining was used to detect cell membrane-mediated apoptosis by FCM.DNA fragmentations were analyzed with DNA gel electrophoresis.Furthermore,telomerase activity was determined with PCR-ELISA-based telomeric repeat amplification(TRAP).Results The proliferation of HL-60 cells was inhibited by Fr4 with an IC_(50) of 115 mg·L~(-1).Typical morphology and biochemical feature of apoptosis was observed with Fr4 60～240 mg·L~(-1).The percentages of early apoptosis cells were increased in a dose-dependent manner.Telomerase activity was decreased in a dose-dependent manner during the process of apoptosis.Conclusion Fr4 induced apoptosis in HL-60 cells.Down-regulation of the telomerase activity in HL-60 cells might be contributed to Fr4-induced apoptosis.