Investigation of antifungal effect of nanoparticle-encapsulated curcumin on CDR1 gene expression in fluconazole-resistant isolates of Candida albicans

Curcumin as a natural phenolic compound derived from Curcuma longa plant has shown an antifungal property. Candida albicans is the most common opportunistic fungal pathogen. Continuous deployment of antifungals against this pathogen has led to the emergence and increasing of the multi-drug resistance. In this study, the effect of nanoparticle-encapsulated curcumin on CDR1 gene expression was evaluated in fluconazole-resistant isolates of C. albicans.
In this study, 6 fluconazole-resistant isolates of C. albicans were treated just by fluconazole (1/2MIC) as the control sample and in the combination with nanoparticle-encapsulated curcumin as the test sample. After 24h, two cell groups were cultured in Sabouraud Dextrose Agar to estimate cell death percentage. Following RNA extraction and cDNA synthesis, CDR1 gene expression was investigated quantitatively by real-time PCR method in both curcumin-treated and untreated cells.
Our findings showed that the combination of fluconazole (1/2MIC) and nanoparticle-encapsulated curcumin treatment reduces the fungal growth by 50% after 24 h. Moreover, quantitative real-time PCR analysis revealed that nanoparticle-encapsulated curcumin decreases the expression level of CDR1.
Our findings suggested that curcumin can inhibit fungal growth through different mechanisms such as decreasing the number of ABC efflux pumps at the cell surface and synergically increases the antifungal effect of fluconazole in resistant isolates of C. albicans.