川芎嗪联合阿糖胞苷对人白血病 U937细胞的增殖、凋亡影响及相关机制的研究

目的：探讨川芎嗪(TMP)联合阿糖胞苷(Ara-c)对白血病细胞株 U937增殖、凋亡的影响及相关机制的研究,为临床寻找有效的化疗增敏剂提供实验依据和理论基础。方法实验分为对照组、TMP 组、Ara-c 组及 TMP 联合 Ara-c 组。应用CCK-8法检测各组细胞的增值抑制率；流式细胞术(FCM)检测各组细胞凋亡率；蛋白质印迹方法检测各组细胞内凋亡相关蛋白 Bcl-2、Bax 的表达情况。结果TMP(0.5 mg·ml-1)组与 Ara-c(0.02,0.04,0.08,0.16μg·ml-1)组联合作用后,U937细胞的增殖抑制率明显高于相同浓度下 Ara-c 组,差异有统计学意义(t =5.38,t =8.23,t =14.61,t =17.31,P 均<0.05)。TMP(0.5 mg·ml-1)联合 Ara-c(0.08μg·ml-1)组的凋亡率(27.32±3.64)明显高于 Ara-c 组(15.07±3.85)%]、TMP 组(3.17±2.20)%]和对照组(1.8±1.18)%](t=12.25,P <0.05；t=24.15,P <0.05；t=25.52,P <0.05)。蛋白质印迹结果显示,Ara-c 能在一定程度上下调 Bcl-2蛋白的表达,上调 Bax 蛋白的表达；联合用药后 Bcl-2、Bax 蛋白表达水平改变更明显(t=6.32,P <0.05,t=2.60,P <0.05；t=39.06,P <0.05,t=41.67,P <0.05)。结论TMP 能够增强 Ara-c 抑制细胞增殖、诱导细胞凋亡的作用,从而提高 U937细胞对 Ara-c 的化疗敏感性,其机制可能与下调抑凋亡蛋白 Bcl-2表达,上调促凋亡蛋白Bax 表达有关。

Inhibitory effect of combination treatment with tetramethylpyrazine and Cytarabine on proliferation and Apoplosis in U937 cell and its mechanism

Objective To investigate the proliferation and cell apoptosis of combination treatment with tetramethylpyrazine (TMP)and Cytarabine (Ara-c)on human leukemia cell line U937 cell and provide experimental evidence and theoretical basis for finding effective chemotherapy sensitizer in clinical study.Methods The experiment was divided into TMP group,Ara-c group,TMP combined with Ara-c group,and the control group.The inhibitory rate of U937 cell proliferation was detected by CCK-8 assay.The apoptotic rate was examined by Flow cytometry (FCM).The expression of Bcl-2 and Bax of U937 cells were measured with immunohistochemical approach.Results TMP (0.5 mg·ml-1 )conbined with Cytarabine (0.02,0.04,0.08, 0.1 6 μg·ml-1 )did be able to inhibited the cell growth,compared with the Ara-c group in corresponding concentrations,the difference was significant(t=5.38,t=8.23,t=14.61,t =1 7.31,P <0.05).The inhibition of combination treatment with Tet-ramethylpyrazine (0.5 μg·ml-1 )and Cytarabine (0.08 μg·ml-1 )was significantly higher than Cytarabine (0.08 μg·ml-1 ) (1 5.07±3.85)%],Tetramethylpyrazine (0.5 mg·ml-1 )(3.1 7 ±2.20)%]and the control(1.8 ±1.18)%],respectively (t=12.25,P <0.05;t=24.1 5,P <0.05;t=25.52,P <0.05).The result of Western blot show that the expression of Bcl-12 was up-regulated and the expression of Bax was down-regulated by Ara-c,to some extent.The expression levels of Bcl-2 and Bax were changed more significantly by combination treatment with TMP and Ara-c than the Ara-c alone (t=6.32,P <0.05,t=2.60,P <0.05;t=39.06,P <0.05,t=41.67,P <0.05).Conclusion Tetramethylpyrazine can apparently inhibit the growth of U937 cell and enhance apoptosis induced by cytarabine,promote the drug-sensitivity to cytarabine.And its molecular mecha-nisms might be related to down-regulation of the Bcl-2 expression and up-regulation of the Bax expression.