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Quinine Enhances Photo-Inactivation of Gram-Negative Bacteria
Leon G Leanse1,2, Pu-Ting Dong3, Xueping S Goh1,2
1Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Background:
Antimicrobial resistance is a significant concern to public health, and there is a pressing need to develop novel antimicrobial therapeutic modalities.
Methods:
In this study, we investigated the capacity for quinine hydrochloride (Q-HCL) to enhance the antimicrobial effects of antimicrobial blue light ([aBL] 405 nm wavelength) against multidrug-resistant (MDR) Gram-negative bacteria in vitro and in vivo.
Results:
Our findings demonstrated the significant improvement in the inactivation of MDR Pseudomonas aeruginosa and Acinetobacter baumannii (planktonic cells and biofilms) when aBL was illuminated during Q-HCL exposure. Furthermore, the addition of Q-HCL significantly potentiated the antimicrobial effects of aBL in a mouse skin abrasion infection model. In addition, combined exposure of aBL and Q-HCL did not result in any significant apoptosis when exposed to uninfected mouse skin.
Conclusions:
In conclusion, aBL in combination with Q-HCL may offer a novel approach for the treatment of infections caused by MDR bacteria.
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