The photodynamic effect of methylene blue and toluidine blue on Candida albicans is dependent on medium conditions.
Due to the increased number of immunocompromised patients, the infections associated with the pathogen of the genus Candida and other fungi have increased dramatically. Photodynamic antimicrobial chemotherapy (PACT) has been presented as a potential antimicrobial therapy, in a process that combines light and a photosensitizing drug, which promotes a phototoxic response by the treated cells. In this work, we studied the effects of the different medium conditions during PACT, using either methylene blue (MB) or toluidine blue (TB) on Candida albicans. The inhibition of the growth produced by PACT was decreased for different pH values (6.0, 7.0, and 8.0) in a buffered medium. The phototoxic effects were observed only in the presence of saline (not buffered medium). PACT was modulated by calcium in a different manner using either MB or TB. Also when using MB both verapamil or sodium azide were able to decrease the phototoxic effects on the C. albicans. These results show that PACT is presented as a new and promising antifungal therapy, however, new studies are necessary to understand the mechanism by which this event occurs.
Instituto de Pesquisa e Desenvolvimento-IP&D, Universidade do Vale do Paraíba-UNIVAP, São José dos Campos, SP, Brazil.
Gabriela Guimarães
GG
Carvalho
Monalisa Poliana
MP
Felipe
Maricilia Silva
MS
Costa
D000935:Antifungal Agents / Q000494:pharmacology*; D002118:Calcium / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects* / Q000254:growth & development; D003470:Culture Media / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008751:Methylene Blue / Q000494:pharmacology*; D017319:Photosensitizing Agents / Q000494:pharmacology*; D019810:Sodium Azide / Q000494:pharmacology; D012965:Sodium Chloride / Q000494:pharmacology; D014048:Tolonium Chloride / Q000494:pharmacology*; D014700:Verapamil / Q000494:pharmacology
D000935:Antifungal Agents; D003470:Culture Media; D017319:Photosensitizing Agents; D014048:Tolonium Chloride; D012965:Sodium Chloride; D019810:Sodium Azide; D014700:Verapamil; D002118:Calcium; D008751:Methylene Blue