Affiliations 

  • 1 Engineering Research Centre of Fujian-Taiwan Special Marine Food Processing and Nutrition, Ministry of Education, Fujian, China; Institute for Medical Research, Ministry of Health Malaysia, Jalan Setia Murni U13/52, 40170 Setia Alam, Malaysia
  • 2 Department of Cardiovascular Sciences and Diabetes Research Centre, University of Leicester, LE1 7RH Leicester, United Kingdom; Institute for Medical Research, Ministry of Health Malaysia, Jalan Setia Murni U13/52, 40170 Setia Alam, Malaysia
  • 3 Department of Cardiovascular Sciences and Diabetes Research Centre, University of Leicester, LE1 7RH Leicester, United Kingdom; Institute for Medical Research, Ministry of Health Malaysia, Jalan Setia Murni U13/52, 40170 Setia Alam, Malaysia. Electronic address: sitisarah.h@moh.gov.my
  • 4 Engineering Research Centre of Fujian-Taiwan Special Marine Food Processing and Nutrition, Ministry of Education, Fujian, China; Institute for Medical Research, Ministry of Health Malaysia, Jalan Setia Murni U13/52, 40170 Setia Alam, Malaysia. Electronic address: jiamiao.hu@fafu.edu.cn
Photodiagnosis Photodyn Ther, 2021 Dec 08;37:102677.
PMID: 34890782 DOI: 10.1016/j.pdpdt.2021.102677

Abstract

BACKGROUND: Pseudomonas aeruginosa (P. aeruginosa) is an emerging opportunistic pathogen, which can cause bacterial skin diseases such as green nail syndrome, interdigital infections and folliculitis. Curcumin-mediated antimicrobial photodynamic therapy (aPDT) has been demonstrated as a promising therapeutic option for the treatment of skin infection though its inactivation of gram-negative bacteria such as P. aeruginosa.

MATERIALS AND METHODS: In the present study, we examined the adjuvant effect of polymyxin B on the antibacterial activity of curcumin-mediated aPDT against P. aeruginosa. P. aeruginosa was treated with curcumin in the presence of 0.1-0.5 mg/L polymyxin B and irradiated by blue LED light (10 J/cm2). Bacterial cultures treated with curcumin alone served as controls. Colony forming units (CFU) were counted and the viability of P. aeruginosa was calculated after aPDT treatment. The possible underlying mechanisms for the enhanced killing effects were also explored.

RESULTS: The killing effects of curcumin-mediated aPDT against P. aeruginosa was significantly enhanced by polymyxin B (over 2-log reductions). Moreover, it was also observed that addition of polymyxin B in the curcumin-mediated aPDT led to the apparent bacterial membrane damage with increased leakage of cytoplasmic contents and extensive DNA and protein degradation.

DISCUSSION: The photodynamic action of curcumin against P. aeruginosa could be significantly enhanced by the FDA-approved drug polymyxin B. Our results highlight the potential of introducing polymyxin B to enhance the effects of aPDT treatment against gram-negative skin infections, in particular, P. aeruginosa.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.