双氢青蒿素对白血病多药耐药K562/ADM细胞的逆转作用

Effect of Dihydroartemisinin on MDR reversal of K562/ADM Cells

目的:探讨双氢青蒿素(Dihydroartemisinin,DHA)在白血病多药耐药中的应用。方法:采用MTT检测DHA联合阿霉素(adriamycin,ADM)对白血病多药耐药细胞(K562/ADM)生长增殖的影响;应用流式细胞技术分析细胞内罗丹明123(Rhodamine 123)浓度,以检测DHA对白血病细胞膜P糖蛋白(P-glycoprotein,P-gp)泵功能的影响;免疫组化方法检测DHA对白血病细胞P-gp表达水平的影响。结果:10、20、40μmol/L DHA实验组的细胞耐药逆转倍数分别为1.46、2.16和3.52倍。DHA使用前、后K562/ADM细胞膜P-gp表达水平无明显差异;Rh123蓄积试验中DHA应用后使K562/ADM细胞内Rh123浓度由用前的22.16%升至89.18%,Rh123外排试验中DHA应用后使K562/ADM细胞内Rh123浓度由用前的27.15%升至60.51%。结论:DHA:能有效逆转白血病细胞的MDR机制为通过抑制肿瘤细胞膜上P-gp的药泵功能,增加耐药细胞内化疗药物浓度逆转耐药性,而不是抑制和P-gp表达。

Objective：To investigate the reversal effect of Dihydroartemisinin（DHA） on multidrug resistance （MDR） of myelogenous leukemia K562/ADM cells and discuss the possible correlative mechanism. Methods： MTT assay was used to evaluate inhibitory effect of DHA combined with adriamyein（ADM）on proliferation of human leukemia cell lines K562/ADM. Intracellular Rhodamine 123 concentrations was analyzed by Flow cytometer. Immunity histochemis- try assay was used to examine the expression of P-glycoprotein （P-gp） on membrane of tumor cells. Results： DHA of 10,20 and 40/anol/L could induce reversal of drug resistance with the reversal index being1.46,2. 16 and 3. 52 times respectively. Expression P-gp had not distinct difference between in DHA used groups with in DHA and unused group Incubation of K562/ADM cells with DHA caused a marked increase in accumulation and a notable decrease in efflux of Rh123. Conclusion.DHA exhibits potent effects in vitro in the reversal of P-gp mediated MDR, and its reversal mecha- nism is that it can increase intracellular chemotherapy drugs concentrations by inhibiting＂bump＇function of P-gp other than P-gp expression.