2-芳基-4-取代喹啉类化合物的抗真菌活性和作用机制研究

Study on antifungal activity and mechanism of 2-aryl-4-substituted quinoline compound

目的开发新型抗真菌药物以解决深部真菌感染发病率和死亡率高、抗真菌药物出现耐药性的临床问题。方法采用抗真菌药敏实验对内部化合物库进行活性筛选,进一步通过微量液基稀释法考察阳性化合物的抗真菌谱;通过生长实验、时间杀菌曲线实验评价阳性化合物对真菌存活的影响;通过倒置显微镜观察化合物对真菌菌丝形成的影响;采用流式细胞仪检测化合物对真菌细胞内活性氧(ROS)生成、生物膜通透性和凋亡的影响。结果2芳基4取代喹啉类化合物J6抗真菌活性最优,对白念珠菌、热带念珠菌、克柔念珠菌、新生隐球菌的最小抑菌浓度分别为18.9、18.9、37.8、37.8 mg/L。J6能明显抑制这4种真菌的生长,甚至对新生隐球菌表现杀菌作用。此外,J6还能抑制真菌菌丝的形成。作用机制研究显示,J6可增加真菌细胞膜通透性和细胞内ROS水平,诱导真菌细胞发生凋亡。结论2芳基4取代喹啉类化合物J6表现出较好的抗真菌活性,对其进一步结构优化和机制研究,有望发现新型的抗真菌药物。

Objective To develop new antifungal drugs to solve the clinical problems of high morbidity and mortality of deep fungal infections and resistance of antifungal drugs.Methods The antifungal susceptibility testing was used to screen the activity of the in-house compound library,and the antifungal spectrum of the positive compounds was evaluated by a broth microdilution method.The effects of positive compounds on fungal survival were evaluated by growth experiments and time-kill assay.The effect of compounds on mycelium formation was observed by inverted microscope.The effects of compounds on reactive oxygen species(ROS)production,biofilm permeability and apoptosis were detected by flow cytometry.Results The 2-aryl-4-substituted quinoline compound J6 had the best antifungal activity,with minimum inhibitory concentration of 18.9,18.9,37.8,and 37.8 mg/L against Candida albicans,Candida tropicalis,Candida krusei and Cryptococcus neoformans,respectively.J6 significantly inhibited the growth of these four fungi,and it even showed fungicidal activity against Cryptococcus neoformans.Additionally,J6 could also suppress hyphal formation.Studies on the mechanism of action revealed that J6 increased the membrane permeability of fungal cells and intracellular ROS level,thus inducing the apoptosis of fungal cells.Conclusion The 2-aryl-4-substituted quinoline compound J6 displayed promising antifungal activity.Further study on its structural optimization and mechanism is expected to discover novel antifungal agents.