TY - JOUR T1 - Reversion of antibiotic resistance in drug-resistant bacteria using non-steroidal anti-inflammatory drug benzydamine JF - bioRxiv DO - 10.1101/2021.05.07.443075 SP - 2021.05.07.443075 AU - Yuan Liu AU - Ziwen Tong AU - Jingru Shi AU - Tian Deng AU - Ruichao Li AU - Xia Xiao AU - Zhiqiang Wang Y1 - 2021/01/01 UR - http://biorxiv.org/content/early/2021/05/07/2021.05.07.443075.abstract N2 - Antimicrobial resistance has been a growing concern that gradually undermines our tradition treatment regimen. The fact that few antibacterial drugs with new scaffolds or targets have been approved in the past two decades aggravates this crisis. Repurposing previously approved drugs as potent antibiotic adjuvants offers a cost-effective strategy to mitigate the development of resistance and tackle the increasing infections by multidrug-resistant (MDR) bacteria. Herein, we found that benzydamine, a widely used non-steroidal anti-inflammatory drug in clinic, remarkably potentiated broad-spectrum antibiotic-tetracyclines activity against a panel of clinical important resistant pathogens, including MRSA, VRE, MCRPEC and tet(X)-positive Gram-negative bacteria. Further mechanistically experiments showed that benzydamine dissipated membrane potential (ΔΨ) in both Gram-positive and negative bacteria, which in turn upregulated the transmembrane proton gradient (ΔpH) and promoted the uptake of tetracyclines. Additionally, benzydamine exacerbated the oxidative stress by triggering the production of ROS and suppressing GAD system-mediated oxidative defensive. This mode of action explains the great bactericidal activity of the doxycycline-benzydamine combination against different metabolic states of bacteria including persister cells. As a proof-of-concept, the in vivo efficacy of this combination therapy was evidenced in multiple animal infection models. These findings revealed that benzydamine is a promising tetracycline antibiotics adjuvant and has the potential to address life-threatening infections by MDR bacteria.Competing Interest StatementThe authors have declared no competing interest. ER -