Author(s):
Silva, Anderson Ramos da ; Andrade Neto, João Batista de ; Silva, Cecília Rocha da ; Campos, Rosana de Sousa ; Silva, Rose Anny Costa ; Freitas, Daniel Domingues ; Nascimento, Francisca Bruna Stefany Aires do ; Andrade, Larissa Nara Dantas de ; Sampaio, Letícia Serpa ; Grangeiro, Thalles Barbosa ; Magalhães, Hemerson Iury Ferreira ; Cavalcanti, Bruno Coêlho ; Moraes Filho, Manoel Odorico de ; Nobre Júnior, Hélio Vitoriano
Date: 2016
Origin: Oasisbr
Subject(s): Berberina; Fluconazol; Fungos; Candida
Description
The incidence of fungal infections and, in particular, the incidence of fungal antibiotic resistance, which is associated with bio- film formation, have significantly increased, contributing to morbidity and mortality. Thus, new therapeutic strategies need to be developed. In this context, natural products have emerged as a major source of possible antifungal agents. Berberine is a pro- toberberine-type isoquinoline alkaloid isolated from the roots, rhizomes, and stem bark of natural herbs, such as Berberis aqui- folium , Berberis vulgaris , Berberis aristata , and Hydrastis canadensis , and of Phellodendron amurense . Berberine has been proven to have broad antibacterial and antifungal activity. In the present study, the potential antifungal effect of berberine against fluconazole-resistant Candida and Cryptococcus neoformans strains, as well as against the biofilm form of Candida spp., was assessed. The antifungal effect of berberine was determined by a broth microdilution method (the M27-A3 method of the Clinical and Laboratory Standards Institute) and flow cytometry techniques, in which the probable mechanism of action of the compound was also assessed. For biofilm assessment, a colorimetric 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to determine the susceptibility of sessile cells. The isolates used in the study belonged to the Lab- oratory of Bioprospection and Experiments in Yeast (LABEL) of the Federal University of Ceará. After 24 and 72 h, fluconazole- resistant Candida and Cryptococcus neoformans strains showed berberine MICs equal to 8 g/ml and 16 g/ml, respectively. Cytometric analysis showed that treatment with berberine caused alterations to the integrity of the plasma and mitochondrial membranes and DNA damage, which led to cell death, probably by apoptosis. Assessment of biofilm-forming isolates after treat- ment showed statistically significant reductions in biofilm cell activity ( P < 0.001).
