背景:由于抗菌素耐药性(AMR)已成为全球健康危机,我们迫切需要针对AMR感染的新策略。Quorumsensing(QS),负责细菌通讯和致病性,是作为抗AMR感染的有希望的治疗方法之一的抗毒力药物的目标之一。
方法:我们确定了一种天然化合物,Harmine,通过基于铜绿假单胞菌三种QS受体的虚拟筛选(P.铜绿假单胞菌),并探讨了Harmine对QS控制和致病性相关表型的影响,包括绿脓苷的产生,细胞外蛋白酶排泄,生物膜的形成,和抽搐运动的铜绿假单胞菌PA14。Harmine对秀丽隐杆线虫的保护作用(C.确定了线虫)和小鼠感染模型,并探索了Harmine与常用抗生素的协同作用。通过分子对接分析阐明了Harmine的QS抑制作用的机制,转录组学分析,和目标验证分析。
结果:体外结果表明Harmine对绿脓苷的产生具有QS抑制作用,细胞外蛋白酶排泄,生物膜的形成,以及铜绿假单胞菌PA14的抽搐运动,体内结果显示Harmine对秀丽隐杆线虫和小鼠感染模型的保护作用。有趣的是,当联合使用时,毒理学会增加PA14和铜绿假单胞菌临床分离株对多粘菌素B和卡那霉素的敏感性。此外,组胺下调了一系列与致病性相关的QS控制基因,其潜在机制可能涉及竞争性拮抗自诱导受体LasR,RhlR,和PqsR。
结论:这项研究揭示了Harmine对QS靶标的潜在抗毒力,建议使用Harmine及其衍生物作为抗毒力化合物。
BACKGROUND: As antimicrobial resistance (AMR) has become a global health crisis, new strategies against AMR infection are urgently needed. Quorum sensing (QS), responsible for bacterial communication and pathogenicity, is among the targets for anti-virulence drugs that thrive as one of the promising treatments against AMR infection.
METHODS: We identified a natural compound,
Harmine, through virtual screening based on three QS receptors of Pseudomonas aeruginosa (P. aeruginosa) and explored the effect of Harmine on QS-controlled and pathogenicity-related phenotypes including pyocyanin production, exocellular protease excretion, biofilm formation, and twitching motility of P. aeruginosa PA14. The protective effect of
Harmine on Caenorhabditis elegans (C. elegans) and mice infection models was determined and the synergistic effect of
Harmine combined with common antibiotics was explored. The underlaying mechanism of Harmine\'s QS inhibitory effect was illustrated by molecular docking analysis, transcriptomic analysis, and target verification assay.
RESULTS: In vitro results suggested that Harmine possessed QS inhibitory effects on pyocyanin production, exocellular protease excretion, biofilm formation, and twitching motility of P. aeruginosa PA14, and in vivo results displayed Harmine\'s protective effect on C. elegans and mice infection models. Intriguingly,
Harmine increased susceptibility of both PA14 and clinical isolates of P. aeruginosa to polymyxin B and kanamycin when used in combination. Moreover, Harmine down-regulated a series of QS controlled genes associated with pathogenicity and the underlying mechanism may have involved competitively antagonizing autoinducers\' receptors LasR, RhlR, and PqsR.
CONCLUSIONS: This study shed light on the anti-virulence potential of Harmine against QS targets, suggesting the possible use of
Harmine and its derivates as anti-virulence compounds.