In Vitro Photodynamic Inactivation of Cryptococcus neoformans Melanized Cells with Chloroaluminum Phthalocyanine Nanoemulsion

Autor(es)

Rodrigues, Gabriela B. ^[1] ; Primo, Fernando L. ^[2] ; Tedesco, Antonio C. ^[2] ; Braga, Gilberto U. L. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Ciencias Farmaceut Ribeirao Preto, Dept Anal Clin Toxicol & Bromatol, BR-14049 Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, BR-14049 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Photochemistry and Photobiology; v. 88, n. 2, p. 440-447, MAR-APR 2012.
• Citações Web of Science: 21

Resumo

The selection of fungi resistant to currently used fungicides and the emergence of new pathogenic species make the development of alternative fungus-control techniques highly desirable. Photodynamic antimicrobial chemotherapy (PACT) is a promising method which combines a nontoxic photosensitizer (PS) with visible light to cause selective killing of microbial cells. The development of PACT to treat mycoses or kill fungi in the environment depends on identifying effective PS for the different pathogenic species and delivery systems able to expand and optimize their use. In the present study, the in vitro susceptibility of Cryptococcus neoformans melanized cells to the photodynamic effects of the PS agent ClAlPc in nanoemulsion (ClAlPc/NE) was examined. Cells were killed in a PS concentration- and light dose-dependent manner. Treatment with ClAlPc/NE, using PS concentrations (e.g. 4.5 mu m) and light doses (e.g. 10 J cm-2) compatible with PACT, resulted in a reduction of up to 6 logs in survival. Washing the cells to remove unbound PS before light exposure did not inhibit fungal photodynamic inactivation. Internalization of ClAlPc by C.neoformans was confirmed by confocal fluorescence microscopy, and the degree of uptake was dependent on PS concentration. (AU)

• Processo FAPESP: 03/07702-9 - Abordagens genômica e proteômica para a identificação de genes e de proteínas envolvidos na tolerância à radiação solar em fungos: aplicações para o desenvolvimento de fotossensibilizadores e para a obtenção de linhagens mais tolerantes à radiação UV
• Beneficiário: Gilberto Úbida Leite Braga
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 06/50562-1 - Avaliacao do uso de laser de baixa potencia e agentes fotossensibilizadores associados a sistemas de liberacao nanoestruturados no tratamento de feridas e/ou outras doencas cutaneas
• Beneficiário: Fernando Lucas Primo
• Modalidade de apoio: Bolsas no Brasil - Doutorado