4种药物外排泵抑制剂对异烟肼抗结核分枝杆菌最低抑菌浓度的影响研究

Effects of the four drug efflux pump inhibitors on MIC of isoniazid for Mycobacterium tuberculosis

目的研究4种药物外排泵抑制剂对异烟肼抗结核分枝杆菌的最低抑菌浓度(minimum inhibitory concentration,MIC)的影响。方法纳入37株单耐异烟肼和10株全敏的结核菌临床分离株以及H37Rv,应用微孔板Alamar blue显色法检测以上菌株分别加入维拉帕米(verapamil,VP)、氯丙嗪(chlorpromazine,CPZ)、硫利哒嗪(thioridazine,TZ)和羰基氰氯苯腙(carbonyl cyanide m-chlorophenyl hydrazone,CCCP)4种外排泵抑制剂前后异烟肼抗结核菌的MIC的变化情况,并用配对χ2检验比较不同抑制剂对异烟肼MIC的影响程度。结果 37株单耐异烟肼结核菌中,分别有64.86%(24/37)、48.65%(18/37)、43.24%(16/37)和37.84%(14/37)的菌株被VP、CPZ、TZ和CCCP降低异烟肼MIC,且均以降低2倍为主,VP致异烟肼MIC降低2倍及以上的菌株数均高于TZ和CCCP,P值均<0.05。6/10的全敏结核菌以及H37Rv的异烟肼MIC被VP降低2倍及以上。结论 4种药物外排泵抑制剂对异烟肼抗结核菌存在不同程度的影响,VP降低异烟肼MIC的作用较强。

Using 37 mono-resistant to isoniazid and 10 pan-sensitive Mycobacterium tuberculosis （M. tuberculosis） clinical isolates and H37Rv, the effects of the four efflux pump inhibitors, verapamil （VP）, chlorpromazine （CPZ）, thioridazine （TZ）, and carbonyl cyanide m-chlorophenyl hydrazone （CCCP）, to the minimum inhibitory concentration （MIC） of isoniazid for M. tuberculosis were studied by means of microplate Alamar blue assay for detecting the changes of isoniazid＇s MIC. χ2 test of paired comparison of enumeration data was used to compared the levels of isoniazid^s MIC changed before and after adding VP, CPZ, TZ, and CCCP. Of 37 M. tuberculosis isolates mono-resistant to isoniazid, the isoniazid＇s MICs in 24 （64.86%）, 18 （48.65%）, 16 （43.24%）, and 14 （37.84%） strains were decreased by VP, CPZ, TZ, and CCCP, respectively. The 2- fold reduction was the most common. The isolates of which＇s MIC of isoniazid reduced by ≥2 fold caused by VP were more than that caused by TZ and CCCP, and the P value was all d0.05. The MICs of 6 of 10 pan-sensitive M. tuberculosis and H37Rv were decreased at least 2 fold by VP. The results show that the efflux pump inhibitors of the four drugs have different influence on the MIC of isoniazid for M. tuberculosis, and VP has the strongest effect for decreasing the MIC of isoniazid.