New Insights in Phenothiazinium-Mediated Photodynamic Inactivation of Candida Auris
In recent years, Candida auris has emerged as a hazardous hospital-acquired pathogen. Its resistance to antifungal treatments makes it challenging, requiring new approaches to manage it effectively. Herein, we aimed to assess the impact of photodynamic inactivation mediated by methylene blue (MB-PDI) or 1,9-dimethyl MB (DMMB-PDI) combined with a red LED against C. auris. To evaluate the photoinactivation of yeasts, we quantified colony-forming units and monitored ROS production. To gain some insights into the differences between MB and DMMB, we assessed lipid peroxidation (LPO) and mitochondrial membrane potential (ΔΨm). After, we verified the effectiveness of DMMB against biofilms by measuring metabolic activity and biomass, and the structures were analyzed through scanning electron microscopy and optical coherence tomography. We also evaluated the cytotoxicity in mammalian cells. DMMB-PDI successfully eradicated C. auris yeasts at 3 μM regardless of the light dose. In contrast, MB (100 μM) killed cells only when exposed to the highest dose of light. DMMB-PDI promoted higher ROS, LPO and ΔΨm levels than those of MB. Furthermore, DMMB-PDI was able to inhibit biofilm formation and destroy mature biofilms, with no observed toxicity in fibroblasts. We conclude that DMMB-PDI holds great potential to combat the global threat posed by C. auris.
Citação
@online{abdênego_r.2023,
author = {Abdênego R. , Silva and Fernanda V. , Cabral and Camila R. ,
Silva and Daniela F. T. , Silva and Anderson Z. , Freitas and
Adriana , Fontes and Martha S. , Ribeiro},
title = {New Insights in Phenothiazinium-Mediated Photodynamic
Inactivation of Candida Auris},
volume = {9},
number = {7},
date = {2023-06-30},
doi = {10.3390/jof9070717},
langid = {pt-BR},
abstract = {In recent years, Candida auris has emerged as a hazardous
hospital-acquired pathogen. Its resistance to antifungal treatments
makes it challenging, requiring new approaches to manage it
effectively. Herein, we aimed to assess the impact of photodynamic
inactivation mediated by methylene blue (MB-PDI) or 1,9-dimethyl MB
(DMMB-PDI) combined with a red LED against C. auris. To evaluate the
photoinactivation of yeasts, we quantified colony-forming units and
monitored ROS production. To gain some insights into the differences
between MB and DMMB, we assessed lipid peroxidation (LPO) and
mitochondrial membrane potential (ΔΨm). After, we verified the
effectiveness of DMMB against biofilms by measuring metabolic
activity and biomass, and the structures were analyzed through
scanning electron microscopy and optical coherence tomography. We
also evaluated the cytotoxicity in mammalian cells. DMMB-PDI
successfully eradicated C. auris yeasts at 3 μM regardless of the
light dose. In contrast, MB (100 μM) killed cells only when exposed
to the highest dose of light. DMMB-PDI promoted higher ROS, LPO and
ΔΨm levels than those of MB. Furthermore, DMMB-PDI was able to
inhibit biofilm formation and destroy mature biofilms, with no
observed toxicity in fibroblasts. We conclude that DMMB-PDI holds
great potential to combat the global threat posed by C. auris.}
}