鼠尾草酸逆转K562/A02细胞多药耐药的机制研究  

Study on reversing mechanism of multidrug resistance of K562/A02 cell line by carnosic acid

作　　者：于晓宁[1] 李颢[1] 陈学良[1] 李湘新[1] 王冉[1] 高芳[1] 

机构地区：[1]山东大学齐鲁医院,济南250012

出　　处：《中华血液学杂志》2010年第6期381-384,共4页Chinese Journal of Hematology

基　　金：国家自然科学基金（30600258）;山东省中青年博士基金（2006BS03061）

摘　　要：目的 探讨鼠尾草酸（Canosic acid,CA）对人类白血病多药耐药（MDR）细胞系K562/A02细胞的逆转作用及机制.方法 MTT法测定CA作用前后K562/A02细胞对阿霉素（ADM）的敏感性.流式细胞术（FCM）和激光扫描共聚焦显微镜（LSCM）测定细胞内ADM的平均荧光强度,计算细胞内ADM浓度.半定量RT-PCR检测细胞mdr1 mRNA表达水平.采用流式细胞术和Western blot 检测细胞膜P糖蛋白（P-gp）表达.结果 CA可将ADM对K562/A02细胞的IC50值由16.31μg/ml降至1.35μg/ml,逆转倍数为12.08倍.流式细胞术检测结果表明CA可将K562/A02细胞内ADM的荧光强度由17.05提高到60.53（P〈0.01）.LSCM结果显示CA可恢复ADM在K562/A02细胞的细胞核和胞质中的弥散分布,并使细胞内ADM的浓度由4.9 Oμg/ml提高至15.4μg/ml.RT-PCR结果显示K562/A02细胞mdr1 mRNA水平明显高于K562细胞,CA处理后K562/A02细胞mdr1 mRNA水平明显降低（P〈0.01）.流式细胞术检测K562/A02细胞膜上P-gp的荧光强度在经CA处理后由44.40降至22.80（P〈0.05）.Western blot结果显示CA处理后的K562/A02细胞膜上P-gp的表达明显降低.结论 在体外,CA可有效逆转人白血病细胞K562/A02的MDR,其逆转耐药的机制可能与P-gp蛋白表达下调并抑制其功能有关.Objective To investigate the effects of carnosic acid（CA）on reversal of the muhidrug resistance（MDR）of human leukemia cell line K562/A02 and its mechanism.Methods MTT assay was used to determine the sensitivity of K562/A02 cells to adriamycin（ADM）pre-and post-treated with CA.Flow cytometry（FCM）and laser scanning confocal microscopy（LSCM）were used to measure intracellular fluorescence intensity and concentration of ADM respectively.The expression level of mdr1 was detected by semi-quantitative RT-PCR.P-glycoprotein（P-gp）expression was detected by FCM and Western blot.Resuits CA decreased,IC50 of ADM in K562/A02 cells from 16.31 μg/mL to 1.35μg/mL,being a 12.08fold decrease.The intracellular ADM fluorescence intensity of K562/A02 was increased from 17.05 t0 60.53after treated with CA（P〈0.01）.In living K562/A02 ceils,after treated with CA,the diffuse distribution of intracellular ADM was recovered in both nuclear and cytoplasm,and the concentration of intracellular ADM increased from 4.93μg/mL to 15.43μg/mL.RT-PCR assay showed that CA inhibited the expressions of mdr1 mRNA in K562/A02 cells（P〈0.01）.Mean fluorescence intensity of P-gp detected by FCM in CA-treated K562/A02 was decreased to 22.80 as compared with that in untreated K562/A02 cells（44.40,P〈0.05）.Conclusion CA can reverse the MDR of K562/A02 cells in vitro.The mechanism may be associated with down-regulation of mdr1 and inhibition of P-gp function.

关 键 词：鼠尾草酸 耐药性 多药 白血病 P糖蛋白 

分 类 号：R285.5[医药卫生—中药学]