雷公藤甲素诱导K562/G01细胞凋亡的线粒体机制研究

Study on mechanism of mitochondrial in K562/G01 cells apoptosis induced by triptolide

目的 探讨雷公藤甲素（TP）诱导慢性粒细胞白血病（CML） K562/G01细胞凋亡的线粒体可能机制.方法 用不同浓度的TP作用于K562/G01细胞,用四甲基偶氮唑蓝（MTT）法检测各实验组的细胞毒性作用,用流式细胞术检测各实验组细胞的凋亡率、线粒体膜电位及Caspase-9活性,用实时荧光定量聚合酶链反应（PCR）法检测Caspase-9及细胞色素C的mRNA水平,用Western blot检测细胞色素C的蛋白水平.结果 TP对K562/G01细胞的生长增殖均有抑制作用,呈时间-剂量依赖性（均P＜ 0.001）.同时TP可以使细胞的线粒体膜电位消退、使Caspase-9的活性增高（均P＜ 0.001）,TP上调Caspase-9和细胞色素C的转录水平（均P＜0.001）及细胞色素C的蛋白表达水平（0、10、20、40、80 nmol/LTP作用48 h后,细胞色素C对应条带灰度值分别为10.54±0.75、21.54±0.59、39.63±0.58、53.29±1.47、75.68±1.87,均P＜ 0.001）,且上述作用均呈明显的剂量依赖性.结论 雷公藤甲素可以有效抑制K562/G01细胞生长增殖,而线粒体凋亡途径很可能是TP促进CML细胞凋亡的多途径之一.

Objective To investigate the possible mechanism of mitochondrial in chronic myeloid leukemia cells K562/G01 cells apoptosis induced by triptolide.Methods K562/G01 cells were treated with different concentrations of triptolide.MTT assay was used to assess cytotoxic effect.FCM was used to determine apoptosis rate,mitochondrial membrane potential and the activity of Caspase-9 of each experimental group.Real-time quantitative PCR assay was used to quantify mRNA levels of Caspase-9 and cytochrome C and Western blot assay was used to determine protein levels of cytochrome C.Results Triptolide inhibited the growth and proliferation of K562/G01 cells in a time-and dose-dependent manner （both P 〈 0.001）.Meantime,triptolide could make the mitochondria membrane potential fade away and enhance the activity of Caspase-9 （F =566.431,2 555.485,P 〈 0.001）.In addition,triptolide could dose-dependently up-regulated the transcription of Caspase-9 and cytochrome C （F =61 007.702,452 121.760,P 〈 0.001）,and the protein expression of cytochrome C,whose gray value in each experimental group was 21.54±0.59,39.63±0.58,53.29± 1.47 and 75.68±1.87 （F =5 677.928,P 〈 0.001） respectively.Conclusion Triptolide could potently inhibit the growth and proliferation of K562/G01 cells,and the mitochondria apoptosis pathway might be one of the important apoptosis mechanisms in chronic myeloid leukemia cells induced by triptolide.