A prenylated flavanone from Dalea elegans inhibits rhodamine 6 G efflux and reverses fluconazole-resistance in Candida albicans

In previous studies, 2,4-dihydroxy-5-(1,1-dimethylallyl)-6- prenylpinocembrin, a prenylated flavonoid isolated from Dalea elegans roots, showed activity against multiresistant Staphylococcus aureus and Candida albicans, as well as an uncoupling effect on mitochondria and antioxidant activity. The ai...

Descripción completa

Detalles Bibliográficos
Autores: Peralta, Mariana Andrea, Calise, Maximiliano, Fornari, M. Cecilia, Ortega, María Gabriela, Diez, Roberto Alejandro, Cabrera, Jose Luis, Pérez, Cristina
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/85037
Acceso en línea:http://hdl.handle.net/11336/85037
Access Level:acceso abierto
Palabra clave:ANTIFUNGAL ACTIVITY
AZOLE - RESISTANT CANDIDA ALBICANS
DALEA ELEGANS
FABACEAE
PRENYLATED FLAVONOID
REVERSION OF FLUCONAZOLE RESISTANCE
RHODAMINE EFFLUX INHIBITION
https://purl.org/becyt/ford/3.3
https://purl.org/becyt/ford/3
Descripción
Sumario:In previous studies, 2,4-dihydroxy-5-(1,1-dimethylallyl)-6- prenylpinocembrin, a prenylated flavonoid isolated from Dalea elegans roots, showed activity against multiresistant Staphylococcus aureus and Candida albicans, as well as an uncoupling effect on mitochondria and antioxidant activity. The aim of this study was to evaluate the inhibitory effects of 2,4-dihydroxy-5-(1,1-dimethylallyl)-6-prenylpinocembrin and fluconazole on the efflux of rhodamine 6 G in azole-resistant C. albicans 12-99 that expresses multidrug transporters Cdr1p, Cdr2p, and Mdr1p. The effect of fluconazole and 2,4-dihydroxy-5-(1,1-dimethylallyl)-6-prenylpinocembrin on rhodamine 6 G efflux was assessed in both azole-sensitive and azole-resistant C. albicans. Between 1 and 1000 M, 2,4-dihydroxy-5-(1,1-dimethylallyl)-6-prenylpinocembrin inhibited rhodamine 6 G efflux only in azole-resistant C. albicans 12-99 in a concentration-dependent manner (IC= 119 M); a competitive effect was observed. It also showed selectivity of action in comparison with other flavanones (6-prenylpinocembrin, isolated from aerial parts of D. elegans, pinocembrin, naringenin, and hesperetin, all at 250 M). To check the possible implications of the inhibition of azole efflux on cell growth, antifungal assays were conducted. Minimal inhibitory concentration values were 150 M for 2,4-dihydroxy-5-(1,1-dimethylallyl)-6-prenylpinocembrin and higher than 400 M for fluconazole. The combination of both compounds at either inhibitory or subinhibitory concentrations was significantly more effective than each compound separately. Minimal inhibitory concentration for fluconazole decreased by more than 400 times in the presence of 100 M 2,4-dihydroxy-5-(1,1-dimethylallyl)-6- prenylpinocembrin, reversing azole resistance and giving values similar to those of azole-sensitive C. albicans. These data are consistent with a dual action of 2,4-dihydroxy-5-(1,1-dimethylallyl)-6-prenylpinocembrin: direct antifungal effect on azole-resistant C. albicans 12-99 and inhibition of azole transporters, which results in reversion of fluconazole resistance.