蟛蜞菊内酯抑制K562／A02细胞P-糖蛋白的表达

Effects of wedelolactone inhibiting expression of P-glycoprotein in K562/A02 cells

目的探讨蟛蜞菊内酯对白血病耐药株K562／A02细胞P．糖蛋白表达的影响。方法以白血病耐药株K562／A02为研究对象，分别加入0．2、2．0、20．0μmol／L蟛蜞菊内酯，预处理24h后收集细胞，四甲基偶氮唑盐比色法测定经蟛蜞菊内酯处理后K562／A02细胞对阿霉素（ADM）敏感性，蛋白质印迹法分析经蟛蜞菊内酯处理后白血病耐药株K562／A02细胞P-糖蛋白表达的变化。结果0．2、2．0、20．0μmol／L浓度的蟛蜞菊内酯对K562／A02的耐药性具有明显逆转作用，对阿霉素药物敏感性的相对逆转效率为23．5％、47．1％和67．7％；不同浓度蟛蜞菊内酯对P．糖蛋白的表达于用药后分别下降25．4％、46％、55．6％。结论蟛蜞菊内酯具有较强的逆转K562／A02细胞多药耐药的作用，其逆转机制可能与下调K562／A02细胞P．糖蛋白的表达有关。

Objective To study the effects of wedelolactone on the expression of P-glycoprotein （P-gp） and to explore the multi-drug resistance reversing mechanism of wedelolactone in K562/A02 cells in vitro. Methods The half maximal inhibitory concentration of ADM in K562/A02 was determined by MTT method. The protein expression level of P-gp was determined by Western blot after wedelolactone pretreatment. Results Wedelolactone remarkably enhanced chemo-sensitivity to ADM of K562/A02 cells. After 0.2, 2, 20 μmol/L different concentration of wedelolactone treatment in 24 h the relative reversal efficiency of K562/A02 to ADM was 23.5%, 47.1% and 67.7%, respectively, according to the results of Western blot, wedelolactone was shown to efficiently inhibit the expression of P-gp （P〈0.05）. The relative efficiency of K562/A02 to ADM was 25.4%,46% and 55.6%, respectively. Conclusion Wedelolactone could modulate P-gp expression, and P-gp expression down regulation may be one of the MDR reversal mechanisms in K562/A02 cells by wedelolactone.