Effect of biogenic selenium nanoparticles on ERG۱۱ and CDR۱ gene expression in both fluconazole-resistant and -susceptible Candida albicans isolates

Background and Purpose: Candida albicans is the most common Candida species (spp.) isolated from fungal infections. Azole resistance in Candida species has been considerably increased in the last decades. Given the toxicity of the antimicrobial drugs, resistance to antifungal agents, and drug interactions, the identification of new antifungal agents seems essential. In this study, we assessed the antifungal effects of biogenic selenium nanoparticles on C. albicans and determined the expression of ERG۱۱ and CDR۱ genes. Materials and Methods: Selenium nanoparticles were synthesized with Bacillus sp. MSH-۱. The ultrastructure of selenium nanoparticles was evaluated with a transmission electron microscope. The antifungal susceptibility test was performed according to the modified Clinical and Laboratory Standards Institute M۲۷-A۳ standard protocol. The expression levels of the CDR۱ and ERG۱۱ genes were analyzed using the quantitative real-time polymerase chain reaction (PCR) assay. Results: The azole-resistant C. albicans and wild type C. albicans strains were inhibited by ۱۰۰ and ۷۰ µg/mL of selenium nanoparticle concentrations, respectively. The expression of CDR۱ and ERG۱۱ genes was significantly down-regulated in these selenium nanoparticle concentrations. Conclusion: As the findings indicated, selenium nanoparticles had an appropriate antifungal activity against fluconazole-resistant and -susceptible C. albicans strains. Accordingly, these nanoparticles reduced the expression of CDR۱ and ERG۱۱ genes associated with azole resistance. Further studies are needed to investigate the synergistic effects of selenium nanoparticles using other antifungal drugs.