Ana Paula Pinto1, Isabela Bueno Rosseti2, Moisés Lopes Carvalho1, Bruna Graziele Marques da Silva1, Carlos Alberto-Silva3, Maricilia Silva Costa4. 1. Instituto de Pesquisa e Desenvolvimento - IP&D, Universidade do Vale do Paraíba - UNIVAP, Av. Shishima Hifumi, 2911, São José dos Campos, SP, Brazil. 2. Anhanguera Educacional, Av. Doutor João Batista de Souza Soares, 4009 - Jardim Morumbi, São José dos Campos, SP, Brazil. 3. Centro de Ciências Naturais e Humanas, Universidade Federal do ABC (UFABC), Rua Arcturus, 03, Bloco Delta, São Bernardo do Campo, SP, Brazil. 4. Instituto de Pesquisa e Desenvolvimento - IP&D, Universidade do Vale do Paraíba - UNIVAP, Av. Shishima Hifumi, 2911, São José dos Campos, SP, Brazil. Electronic address: mscosta@univap.br.
Abstract
BACKGROUND: Candida albicans is an opportunistic fungus producing both superficial and systemic infections, especially in immunocompromised individuals. It has been demonstrated that C. albicans ability to form biofilms is a crucial process for colonization and virulence. Furthermore, a correlation between the development of drug resistance and biofilm maturation at Candida biofilms has been shown. Photodynamic Antimicrobial Chemotherapy (PACT) is a potential antimicrobial therapy that combines visible light and a non-toxic dye, known as a photosensitizer, producing reactive oxygen species (ROS) that can kill the treated cells. The objective of this study was to investigate the effects of PACT, using Toluidine Blue O (TBO) on the viability of biofilms produced by C. albicans at different stages of development. METHODS: In this study, the effects of PACT on both biofilm formation and viability of the biofilm produced by C. albicans were studied. Biofilm formation and viability were determined by a metabolic assay based on the reduction of XTT assay. In addition, the morphology of the biofilm was observed using light microscopy. RESULTS: PACT inhibited both biofilm formation and viability of the biofilm produced by C. albicans. Furthermore, PACT was able to decrease the number of both cells and filamentous form present in the biofilm structure. This inhibitory effect was observed in both early and mature biofilms. CONCLUSIONS: The results obtained in this study demonstrated the potential of PACT (using TBO) as an effective antifungal therapy, including against infections associated with biofilms at different stages of development.
BACKGROUND:Candida albicans is an opportunistic fungus producing both superficial and systemic infections, especially in immunocompromised individuals. It has been demonstrated that C. albicans ability to form biofilms is a crucial process for colonization and virulence. Furthermore, a correlation between the development of drug resistance and biofilm maturation at Candida biofilms has been shown. Photodynamic Antimicrobial Chemotherapy (PACT) is a potential antimicrobial therapy that combines visible light and a non-toxic dye, known as a photosensitizer, producing reactive oxygen species (ROS) that can kill the treated cells. The objective of this study was to investigate the effects of PACT, using Toluidine Blue O (TBO) on the viability of biofilms produced by C. albicans at different stages of development. METHODS: In this study, the effects of PACT on both biofilm formation and viability of the biofilm produced by C. albicans were studied. Biofilm formation and viability were determined by a metabolic assay based on the reduction of XTT assay. In addition, the morphology of the biofilm was observed using light microscopy. RESULTS: PACT inhibited both biofilm formation and viability of the biofilm produced by C. albicans. Furthermore, PACT was able to decrease the number of both cells and filamentous form present in the biofilm structure. This inhibitory effect was observed in both early and mature biofilms. CONCLUSIONS: The results obtained in this study demonstrated the potential of PACT (using TBO) as an effective antifungal therapy, including against infections associated with biofilms at different stages of development.
Authors: Diego Dantas Lopes Dos Santos; João Felipe Besegato; Priscila Borges Gobbo de Melo; João Augusto Oshiro Junior; Marlus Chorilli; Dongmei Deng; Vanderlei Salvador Bagnato; Alessandra Nara de Souza Rastelli Journal: Lasers Med Sci Date: 2021-10-19 Impact factor: 3.161