龙葵碱对白血病K562/ADR细胞多药耐药性的逆转作用及其分子机制

Reversal effect of solanine on multidrug-resistance of leukemia K562/ADR cells and its mechanism

目的:研究中药龙葵碱对白血病耐药细胞株K562/ADR多药耐药性的影响,并进一步探讨其作用机制。方法:不同质量浓度(5~40μg/mL)的龙葵碱单独或联合多柔比星(doxorubicin,DOX)作用K562/ADR细胞24 h后,采用CCK-8法检测龙葵碱的细胞毒性及对DOX的增敏作用;FCM法检测细胞内DOX平均荧光强度的变化;蛋白质印迹法检测多药耐药相关蛋白1(multidrug resistance-associated protein 1,MRP1)、c-Jun氨基末端激酶(c-Jun NH2-terminal kinase,JNK)和磷酸化JNK(phosphorylated JNK,p-JNK)的表达变化。结果:无毒剂量(5和10μg/mL)的龙葵碱可明显增强DOX对K562/ADR细胞的毒性(P值均<0.05),而且明显提高细胞内DOX的平均荧光强度(P值均<0.05),且呈一定的剂量依赖性。经5和10μg/mL的龙葵碱处理后,K562/ADR细胞中MRP1和p-JNK蛋白的表达水平均明显下调(P值均<0.05)。结论:龙葵碱在体外可有效逆转K562/ADR细胞的多药耐药性,其机制可能与阻滞JNK信号通路并下调MRP1表达有关。

Objective： To investigate the effect of solanine on multidrug resistance of leukemia K562/ADR cells, and to explore its mechanism. Methods＂ K562/ADR cells were treated with different concentrations （5-40 μg/mL） of solanine alone or in combination with doxorubicin （DOX） for 24 h. The intracellular toxicity and DOX-sensitization effect of solanine were detected by CCK-8 assay. The cell-associated mean fluorescence intensity of DOX was detected by FCM method. The expressions of multidrug resistance-associated protein 1 （MRP1）, c-Jun NH2-terminal kinase （JNK）, and phosphorylated JNK （p-JNK） were determined by Western blotting. Results： Solanine at non-toxic doses （5 and 10 ~g/mL） significantly enhanced the cytotoxicity of DOX （both P 〈 0.05）, and significantly increased the mean fluorescence intensity of DOX in K562/ADR cells in a dose-dependent manner （both P 〈 0.05）. After treatment with 5 and 10 ~g/mL solanine, the expression levels of MRP1 and p-JNK proteins were significantly decreased （all P 〈 0.05） in K562/ADR cells. Conclusion： Solanine can reverse multidrug mechanism may be related to blocking JNK expression resistance of K562/ADR cells in vitro. The signaling pathway and downregulating MRP1