Interaction of Candida albicans with Fluconazole/ Clotrimazole: Effect on Hyphae Formation and Expression of Hyphal Wall Protein 1

Abstract

Background and Aims: Candida albicans (C. albicans) is the most common opportunistic human pathogen. Therapeutic options for Candida infections are limited to available antifungal drugs. The aim of this study was to investigate the effects of fluconazole/clotrimazole (FLU/CLT) on C. albicans hyphae formation.

Materials and Methods: We have established the effectiveness of the combination of FLU/CLT on C. albicans hyphae formation. Interaction of C. albicans with combination of FLU/CLT was performed using the CLSI guidelines and time-killing curves. We investigated the anti-hyphal activities of combination of FLU/CLT against C. albicans using XTT and crystal violet assays as well as scanning electron microscopy and expression of HWP1 gene.

Results: The interaction of C. albicans with FLU/CLT resulted in synergistic, partial synergistic and indifferent effects. The interaction of FLU/CLT were confirmed by time-killing curves. FLU/CLT combined resulted in the reduction of metabolic activity and hyphae formation in C. albicans. Images taken by scanning electron microscopy indicated the effectiveness on hyphae disruption. According to relative real time polymerase chain reaction analysis, the mean Ct values revealed the significant decrease in expression level of the HWP1 gene. A 2.86- and 2.33-fold decrease in HWP1 gene expression was observed in combination of FLU/CLT treatment at 2× minimum inhibitory concentration and 1× minimum inhibitory concentration, respectively (p=0.002).

Conclusions: We confirmed that the hyphae is a target for the combination of FLU/CLT in C. albicans. HWP1 gene is likely to be considered as a probable targets synergistic interaction of FLU/CLT against C. albicans.