Avaliação in vitro da berberina frente às cepas de Candida spp. e Cryptococcus neoformans resistentes ao fluconazol e sua atividade em isolados formadores de biofilme

• Ano de defesa: 2015
• Autor(a) principal: Silva, Anderson Ramos da
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Candida; Cryptococcus neoformans; Biofilmes; Berberina
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/16369

Currently, the incidence of fungal infections has increased significantly, contributing to morbidity and mortality. It has as one of its main causes the increase of antibiotic resistance. Recently associated with biofilm production, which has a high level of antibiotic resistance, coupled with the limited antifungal pharmacological when compared to antibacterial, it leads to the need for the development of new therapeutic strategies. The berberine has shown to have broad antibacterial and antifungal activity. In this context, the objective was to evaluate the antifungal potential of berberine against strains of Candida spp. and Cryptococcus neoformans resistant to fluconazole and evaluate the effect of berberine against strains of Candida tropicalis in biofilm formation. The evaluation of the antifungal effect was determined by microdilution in broth (M27-A3) and by flow cytometry techniques, in which the likely mechanism of action of that compound was evaluated. For the assessment of the biofilm, a colorimetric assay (MTT) was used to determine the susceptibility of sessile cells. Strains of Candida spp. and Cryptococcus neoformans resistant to fluconazole after 24h and 72h showed the minimum inhibitory concentration (MIC) equal to 8 μg/mL and 16-24 μg/ml, respectively. It demonstrates a significant antifungal activity, which, in accordance with cytometry, after the cells were treated with berberine, promoted damage to DNA, changes in the integrity of the plasma and mitochondrial membrane, caused and probably led to cell death by apoptosis. Regarding isolated biofilm formers, when exposed to berberine, they showed a MIC of less than 37.5 mg/mL (MIC 50%), causing a statistically significant reduction in the cellular activity of the biofilm (P <0.001). Therefore, considering these activities, coupled with the lack of studies related to biotechnological development of a phytoproduct, berberine becomes a source of promising molecules with antifungal properties.