表没食子儿茶素没食子酸酯诱导肝癌细胞凋亡并伴随端粒酶活性下调

目的 :探讨表没食子儿茶素没食子酸酯 (EGCG)对肝癌细胞凋亡和端粒酶活性的影响。方法 :用MTT法测定EGCG的细胞毒 ,以荧光显微镜、流式细胞仪研究细胞凋亡 ,PCR -ELISA法测定细胞端粒酶活性。结果 :EGCG作用Bel- 74 0 2肝癌细胞后 ,荧光显微镜观察到细胞凋亡现象。在一定时间、一定剂量范围内 ,EGCG诱导细胞凋亡呈现浓度和时间依赖性 ,而端粒酶活性随EGCG诱导Bel - 74 0 2细胞凋亡的发生而逐渐降低。结论 :EGCG可通过下调端粒酶活性诱导BEL - 74 0 2细胞凋亡 ,这可能是茶叶有效成分抗肿瘤的重要机制之一。

Effect of (-)Epigallocatechin-3-gallate on Apoptosis and Telomerase Activity of Hepatoma Cells

Objective: To explore the effects of (-)epigallocatechin-3-gallate(EGCG) on apoptosis and telomerase activity of hepatoma cells. Methods: The cytotoxicity of EGCG on Bel-7402 cells was tested by MTT assay with minor modification. Apoptosis was determined by fluorescence microscope and flow cytometry analysis. And PCR-ELISA assay was used to detected telomerase activity.Results: After Bel-7402 cells were treated with EGCG, apoptosis was induced and characterized by condensation of the nuclear chromatin, margination against the nuclear envelope, and apoptotic body formation with fluorescence microscope. Flow cytometry revealed that EGCG-induces apoptosis had a increased trendy of concentration and time dependency, whereas telomerase activity was decreased in a time and concentration dependent manner during EGCG induced apoptosis of Bel-7402 cells. Conclusion: EGCG induced apoptosis in Bel-7402 cells by down-regulation telomerase activity, and it may be a major mechanism for anti-tumour of tea compounds.