Synergistic effect of nystatin combined with NSAIDs on Candida biofilm

Candida biofilm on the surface of prosthesis is an important factor in the pathogenesis of denture stomatitis. Prostaglandins are recently known to be produced by C. albicans and may play a role in fungal colonization. The mechanism of action of NSAIDs is the inhibition of prostaglandins production. Therefore, the combination of NSAIDs with nystatin may increase the antifungal effect of this fungicidal polyene compound. Objective: To investigate the in vitro antifungal effect of the combination of nystatin with either ibuprofen or aspirin against C. albicans biofilm on the surface of acrylic resin. Methods: Candida albicans strain DMST 21424 was grown in Sabouraud dextrose broth. Candida albicans biofilm was established for 6 days on the surface of heat cured acrylic resin plate size 10x10X2 mm before the antifungal effect of nystatin with the combination was examined. The MICs of nystatin, aspirin, and ibuprofen against planknotic Candida were performed by broth microdilution method following the NCCLS guideline. Control group was Candida coated-acrylic resin treated with PBS. Optical density (OD520) was used for the quantitative measurement of the number of Candida remaining on the plate after incubation with drugs for 24 hrs. OD520from test groups were compared to those of control groups and calculated as the percentage of Candida reduction. Results: The MIC of nystatin was 1µg/ml, while those of ibuprofen and aspirin were 2048 µg/ml, and 512µg/ml respectively. The combination of nystatin with aspirin significantly increased the percentage of Candida reduction when the concentration of nystatin was ¼ MIC (P <0.05). The synergistic antifungal effect also exhibited in response to the combination of nystatin and ibuprofen. Conclusion: The in vitro antifungal effect of nystatin against Candida albicans biofilm on acrylic resin could be elevated by the interaction of nystatin with either aspirin, or ibuprofen.