Controlling methylene blue aggregation: a more efficient alternative to treat Candida albicans infections using photodynamic therapy

Autor(es)

da Collina, Gabriela Alves ^[1] ; Freire, Fernanda ^[1] ; da Costa Santos, Thabata Paulino ^[1] ; Sobrinho, Natalia Gesse ^[1] ; Aquino, Simone ^[2] ; Prates, Renato Araujo ^[1] ; Teixeira da Silva, Daniela de Fatima ^[1] ; Ratto Tempestini Horliana, Anna Carolina ^[1] ; Pavani, Christiane ^[1]

Afiliação do(s) autor(es)

^[1] Univ Nove Julho UNINOVE, Postgrad Program Biophoton Appl Hlth Sci, Sao Paulo - Brazil

^[2] Univ Nove Julho UNINOVE, Profess Masters Program Adm Hlth Syst Management, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES; v. 17, n. 10, p. 1355-1364, OCT 1 2018.
• Citações Web of Science: 5

Resumo

Methylene Blue (MB) has been widely used in antimicrobial Photodynamic Therapy (aPDT), however, the mechanisms of action (Type I or Type II) are defined by its state of aggregation. In this sense, the identification of the relationships between aggregation, the mechanisms of action and the effectiveness against microorganisms, as well as the establishment of the means and the formulations that may favor the most effective mechanisms, are essential. Thus, the objective of this study was to assess the in vitro aPDT efficacies against Candida albicans, by using MB in vehicles which may influence the aggregation and present an oral formulation (OF) containing MB, to be used in clinical aPDT procedures. The efficacy of MB at 20 mg L-1 was tested in a range of vehicles (water, physiological solution - NaCl 0.9%, phosphate saline buffer - PBS, sodium dodecyl sulfate 0.25% - SDS and urea 1 mol L-1) in a C. albicans planktonic culture, when using 4.68 J cm(-2) of 640 +/- 12 nm LED for the irradiations, as well as 5 minutes of pre-irradiation time, together with measuring the UFC mL(-1). Based upon these analyses, an OF containing MB in the most effective vehicle was tested in the biofilms, as a proposal for clinical applications. When comparing some of the vehicles, sodium dodecyl sulfate was the only one that enhanced an MB aPDT efficacy in a planktonic C. albicans culture. This OF was tested in the biofilms and 50 mg L-1 MB was necessary, in order to achieve some reduction in the cell viabilities after the various treatments. The light dosimetries still need further adaptations, in order for this formulation to be used in clinical applications. The present research has indicated that the development of this formulation for the control of MB aggregations may result in more effective clinical protocols. (AU)

• Processo FAPESP: 16/13488-0 - Influência do meio na eficiência fotodinâmica de azul de metileno na intativação de Candida albicans
• Beneficiário: Natalia Gesse Sobrinho
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 12/50680-5 - Fotossensibilização nas ciências da vida
• Beneficiário: Mauricio da Silva Baptista
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 16/03037-0 - Agregação de fotossensibilizadores e suas implicações nos mecanismos fotoquímicos e na efetividade da Terapia Fotodinâmica
• Beneficiário: Christiane Pavani
• Modalidade de apoio: Auxílio à Pesquisa - Regular