Bactericidal effect of photodynamic therapy, alone or in combination with mupirocin or linezolid, on Staphylococcus aureus
Author
Nonell, Santi
Pérez-Laguna, Vanesa
Pérez-Artiaga, Luna
Lampaya-Pérez, Verónica
García-Luque, Isabel
Ballesta, Sofía
Paz-Cristobal, Manuel P.
Gilaberte, Yolanda
Rezusta, Antonio
Other authors
Universitat Ramon Llull. IQS
Publication date
2017-05Abstract
Antibiotic treatments frequently fail due to the development of antibiotic resistance, underscoring the need for new treatment strategies. Antimicrobial photodynamic therapy (aPDT) could constitute an alternative therapy. In bacterial suspensions of Staphylococcus aureus, which is commonly implicated in cutaneous and mucosal infections, we evaluated the in vitro efficacy of aPDT, using the photosensitizing agents rose bengal (RB) or methylene blue (MB), alone or combined with the antibiotics mupirocin (MU) or linezolid (LN). RB or MB, at concentrations ranging from 0.03 to 10 μg/ml, were added to S. aureus ATCC 29213 suspensions containing >108 cells/ml, in the absence or presence of MU or LN (1 or 10 μg/ml). Suspensions were irradiated with a white metal halide (λ 420–700 nm) or light-emitting diode lamp (λ 515 and λ 625 nm), and the number of viable bacteria quantified by counting colony-forming units (CFU) on blood agar. Addition of either antibiotic had no significant effect on the number of CFU/ml. By contrast, RB-aPDT and MB-aPDT effectively inactivated S. aureus, as evidenced by a 6 log10 reduction in bacterial growth. In the presence of MU or LN, the same 6 log10 reduction was observed in response to aPDT, but was achieved using significantly lower concentrations of the photosensitizers RB or MB. In conclusion, the combination of MU or LN and RB/MB-aPDT appears to exert a synergistic bactericidal effect against S. aureus in vitro.
Document Type
Article
Published version
Language
English
Subject (CDU)
615 - Pharmacology. Therapeutics. Toxicology
Keywords
Estafilococs daurats
Antibiòtics
Fototeràpia
Staphylococcus aureus
Antibiotics
Rose Bengal
Methylene blue
Photoinactivation
Pages
9 p.
Publisher
Frontiers Media
Is part of
Frontiers in Microbiology. Vol. 8 (2017), 1002
Grant agreement number
info:eu-repo/grantAgreement/MINECO/PN I+D/CTQ2013-48767-C3-1-R
info:eu-repo/grantAgreement/MINECO/PN I+D/CTQ2013-48767-C3-2-R
This item appears in the following Collection(s)
Rights
© L'autor/a
Except where otherwise noted, this item's license is described as http://creativecommons.org/licenses/by/4.0/