Antifungal activity of aspirin in combination with fluconazole against Candida albicans biofilms

Abstract

Objective To assess antifungal activity of aspirin and fluconazole administered alone or in combination against Candida albicans biofilms in vitro,and to evaluate the combined effect of these two drugs. Methods The MIC50of aspirin and fluconzole against biofilm-associated adherent cells were determined respectively,then the efficacy of combinations of aspirin and fluconazole were evaluated by calculating the fractional inhibitory concentration (FIC) index.The influence of aspirin on the mRNA expression of gene ALS3,HWP1 in biofilm cells were analyzed by fluorescent quantitative PCR assay. Results The MIC50of aspirin for ATCC64550,clinical strains 14215,15346,15538,16335 were>1440 mg/L,>1440 mg/L,1440 mg/L,720 mg/L and 1440 mg/L respectively,the MIC50of fluconazole for biofilms cells of all the strains were>64 mg/L.Aspirin did not enhance the antifungal effect of fluconazole against biofilm formed by ATCC64550,but synergistic and additive effects were found for the combination of aspirin and fluconazole to block the biofilm formation by clinical isolates (FIC index=0.75,0.5,0.75,0.75).Quantitative real-time PCR analysis showed aspirin could reduce the transcript level of ALS3 and HWP1. Conclusion Aspirin could inhibit C. albicans biofilm formation; it may increase the sensitivity of biofilm cells of C.albicans to fluconazole.(Chin J Lab Med,2013,36:569-572) Key words: Candidaalbicans; Biofilms; Aspirin; Fluconazole