Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections

Autores
Mariani, Florencia; Costilla, Celeste Rocío; Oppezzo, Oscar Juan; Galvan, Estela Maria
Año de publicación
2026
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Diabetic foot ulcer (DFU) infections frequently involve biofilm formation and exhibit limited responsiveness to conventional antibiotic therapy. In particular, Pseudomonas aeruginosa often participates in mono- and polymicrobial biofilms that display high tolerance to antimicrobial agents. This study evaluated the efficacy of methylene blue-mediated antimicrobial photodynamic therapy (aPDT), alone and in combination with antibiotics, against P. aeruginosa biofilms formed either as single-species or in mixed communities with Enterococcus faecalis, under conditions mimicking DFU infections. Macrocolony biofilms were challenged with amikacin alone (for single-species biofilms) or amikacin plus ampicillin (for mixed biofilms), aPDT, or sequential combinations of these treatments, and bacterial viability was quantified by colony-forming unit enumeration. Antibiotic treatment alone produced only modest reductions in P. aeruginosa viability, even at high concentrations, while aPDT using methylene blue was effective only at high photosensitizer concentrations. In contrast, sequential treatment with antibiotics followed by aPDT and a second antibiotic challenge resulted in a marked reduction in P. aeruginosa viability in both mono- and polymicrobial biofilms. Scanning electron microscopy revealed extensive structural damage in P. aeruginosa cells following combined treatments, whereas E. faecalis remained unaffected. Overall, our findings demonstrate that combining aPDT with antibiotics significantly enhances antibiofilm activity against P. aeruginosa, highlighting this approach as a promising alternative for the management of biofilm-associated DFU infections.
Fil: Mariani, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina
Fil: Costilla, Celeste Rocío. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina
Fil: Oppezzo, Oscar Juan. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina
Fil: Galvan, Estela Maria. Comisión Nacional de Energía Atómica; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Materia
PSEUDOMONAS AERUGINOSA
DIABETIC FOOT ULCER
BIOFILM
ANTIBIOTICS
METHYLEBE BLUE-MEDIATED PHOTODYNAMIC THERAPY
SEQUENTIAL ANTIBIOFILM TREATMENT
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/286241
Acceder
id CONICETDig_7866bbddef0ed498dee5f01e0d4e3993
oai_identifier_str oai:ri.conicet.gov.ar:11336/286241
network_acronym_str CONICETDig
repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer InfectionsMariani, FlorenciaCostilla, Celeste RocíoOppezzo, Oscar JuanGalvan, Estela MariaPSEUDOMONAS AERUGINOSADIABETIC FOOT ULCERBIOFILMANTIBIOTICSMETHYLEBE BLUE-MEDIATED PHOTODYNAMIC THERAPYSEQUENTIAL ANTIBIOFILM TREATMENThttps://purl.org/becyt/ford/1.6https://purl.org/becyt/ford/1Diabetic foot ulcer (DFU) infections frequently involve biofilm formation and exhibit limited responsiveness to conventional antibiotic therapy. In particular, Pseudomonas aeruginosa often participates in mono- and polymicrobial biofilms that display high tolerance to antimicrobial agents. This study evaluated the efficacy of methylene blue-mediated antimicrobial photodynamic therapy (aPDT), alone and in combination with antibiotics, against P. aeruginosa biofilms formed either as single-species or in mixed communities with Enterococcus faecalis, under conditions mimicking DFU infections. Macrocolony biofilms were challenged with amikacin alone (for single-species biofilms) or amikacin plus ampicillin (for mixed biofilms), aPDT, or sequential combinations of these treatments, and bacterial viability was quantified by colony-forming unit enumeration. Antibiotic treatment alone produced only modest reductions in P. aeruginosa viability, even at high concentrations, while aPDT using methylene blue was effective only at high photosensitizer concentrations. In contrast, sequential treatment with antibiotics followed by aPDT and a second antibiotic challenge resulted in a marked reduction in P. aeruginosa viability in both mono- and polymicrobial biofilms. Scanning electron microscopy revealed extensive structural damage in P. aeruginosa cells following combined treatments, whereas E. faecalis remained unaffected. Overall, our findings demonstrate that combining aPDT with antibiotics significantly enhances antibiofilm activity against P. aeruginosa, highlighting this approach as a promising alternative for the management of biofilm-associated DFU infections.Fil: Mariani, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; ArgentinaFil: Costilla, Celeste Rocío. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; ArgentinaFil: Oppezzo, Oscar Juan. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; ArgentinaFil: Galvan, Estela Maria. Comisión Nacional de Energía Atómica; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaMultidisciplinary Digital Publishing Institute2026-02info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/286241Mariani, Florencia; Costilla, Celeste Rocío; Oppezzo, Oscar Juan; Galvan, Estela Maria; Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections; Multidisciplinary Digital Publishing Institute; Pathogens; 15; 2; 2-2026; 1-172076-0817CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/url/https://www.mdpi.com/2076-0817/15/2/226info:eu-repo/semantics/altIdentifier/doi/10.3390/pathogens15020226info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2026-08-25T14:37:31Zoai:ri.conicet.gov.ar:11336/286241instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982026-08-25 14:37:31.88CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections
title Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections
spellingShingle Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections
Mariani, Florencia
PSEUDOMONAS AERUGINOSA
DIABETIC FOOT ULCER
BIOFILM
ANTIBIOTICS
METHYLEBE BLUE-MEDIATED PHOTODYNAMIC THERAPY
SEQUENTIAL ANTIBIOFILM TREATMENT
title_short Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections
title_full Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections
title_fullStr Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections
title_full_unstemmed Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections
title_sort Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections
dc.creator.none.fl_str_mv Mariani, Florencia
Costilla, Celeste Rocío
Oppezzo, Oscar Juan
Galvan, Estela Maria
author Mariani, Florencia
author_facet Mariani, Florencia
Costilla, Celeste Rocío
Oppezzo, Oscar Juan
Galvan, Estela Maria
author_role author
author2 Costilla, Celeste Rocío
Oppezzo, Oscar Juan
Galvan, Estela Maria
author2_role author
author
author
dc.subject.none.fl_str_mv PSEUDOMONAS AERUGINOSA
DIABETIC FOOT ULCER
BIOFILM
ANTIBIOTICS
METHYLEBE BLUE-MEDIATED PHOTODYNAMIC THERAPY
SEQUENTIAL ANTIBIOFILM TREATMENT
topic PSEUDOMONAS AERUGINOSA
DIABETIC FOOT ULCER
BIOFILM
ANTIBIOTICS
METHYLEBE BLUE-MEDIATED PHOTODYNAMIC THERAPY
SEQUENTIAL ANTIBIOFILM TREATMENT
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv Diabetic foot ulcer (DFU) infections frequently involve biofilm formation and exhibit limited responsiveness to conventional antibiotic therapy. In particular, Pseudomonas aeruginosa often participates in mono- and polymicrobial biofilms that display high tolerance to antimicrobial agents. This study evaluated the efficacy of methylene blue-mediated antimicrobial photodynamic therapy (aPDT), alone and in combination with antibiotics, against P. aeruginosa biofilms formed either as single-species or in mixed communities with Enterococcus faecalis, under conditions mimicking DFU infections. Macrocolony biofilms were challenged with amikacin alone (for single-species biofilms) or amikacin plus ampicillin (for mixed biofilms), aPDT, or sequential combinations of these treatments, and bacterial viability was quantified by colony-forming unit enumeration. Antibiotic treatment alone produced only modest reductions in P. aeruginosa viability, even at high concentrations, while aPDT using methylene blue was effective only at high photosensitizer concentrations. In contrast, sequential treatment with antibiotics followed by aPDT and a second antibiotic challenge resulted in a marked reduction in P. aeruginosa viability in both mono- and polymicrobial biofilms. Scanning electron microscopy revealed extensive structural damage in P. aeruginosa cells following combined treatments, whereas E. faecalis remained unaffected. Overall, our findings demonstrate that combining aPDT with antibiotics significantly enhances antibiofilm activity against P. aeruginosa, highlighting this approach as a promising alternative for the management of biofilm-associated DFU infections.
Fil: Mariani, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina
Fil: Costilla, Celeste Rocío. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina
Fil: Oppezzo, Oscar Juan. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina
Fil: Galvan, Estela Maria. Comisión Nacional de Energía Atómica; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
description Diabetic foot ulcer (DFU) infections frequently involve biofilm formation and exhibit limited responsiveness to conventional antibiotic therapy. In particular, Pseudomonas aeruginosa often participates in mono- and polymicrobial biofilms that display high tolerance to antimicrobial agents. This study evaluated the efficacy of methylene blue-mediated antimicrobial photodynamic therapy (aPDT), alone and in combination with antibiotics, against P. aeruginosa biofilms formed either as single-species or in mixed communities with Enterococcus faecalis, under conditions mimicking DFU infections. Macrocolony biofilms were challenged with amikacin alone (for single-species biofilms) or amikacin plus ampicillin (for mixed biofilms), aPDT, or sequential combinations of these treatments, and bacterial viability was quantified by colony-forming unit enumeration. Antibiotic treatment alone produced only modest reductions in P. aeruginosa viability, even at high concentrations, while aPDT using methylene blue was effective only at high photosensitizer concentrations. In contrast, sequential treatment with antibiotics followed by aPDT and a second antibiotic challenge resulted in a marked reduction in P. aeruginosa viability in both mono- and polymicrobial biofilms. Scanning electron microscopy revealed extensive structural damage in P. aeruginosa cells following combined treatments, whereas E. faecalis remained unaffected. Overall, our findings demonstrate that combining aPDT with antibiotics significantly enhances antibiofilm activity against P. aeruginosa, highlighting this approach as a promising alternative for the management of biofilm-associated DFU infections.
publishDate 2026
dc.date.none.fl_str_mv 2026-02
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/286241
Mariani, Florencia; Costilla, Celeste Rocío; Oppezzo, Oscar Juan; Galvan, Estela Maria; Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections; Multidisciplinary Digital Publishing Institute; Pathogens; 15; 2; 2-2026; 1-17
2076-0817
CONICET Digital
CONICET
url http://hdl.handle.net/11336/286241
identifier_str_mv Mariani, Florencia; Costilla, Celeste Rocío; Oppezzo, Oscar Juan; Galvan, Estela Maria; Combined Effects of Amikacin and Methylene Blue-Mediated Photodynamic Therapy on Pseudomonas aeruginosa Biofilms Mimicking Mono- and Polymicrobial Diabetic Foot Ulcer Infections; Multidisciplinary Digital Publishing Institute; Pathogens; 15; 2; 2-2026; 1-17
2076-0817
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/url/https://www.mdpi.com/2076-0817/15/2/226
info:eu-repo/semantics/altIdentifier/doi/10.3390/pathogens15020226
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
application/pdf
dc.publisher.none.fl_str_mv Multidisciplinary Digital Publishing Institute
publisher.none.fl_str_mv Multidisciplinary Digital Publishing Institute
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
_version_ 1874774331755593728
score 13.24418

Publicaciones similares