The postantifungal effect of nystatin and its impact on adhesion attributes of oral Candida dubliniensis isolates

Abstract

The postantifungal effect (PAFE) has an impact on candidal pathogenicity. However, there is no information on either the PAFE or its impact on adhesion traits of oral Candida dubliniensis isolates. Oral candidosis can be treated topically with nystatin. Adhesion to buccal epithelial cells (BEC), germ tube (GT) formation and relative cell surface hydrophobicity (CSH) are all colonisation attributes of candidal pathogenicity. Hence, the main objective of this study was to investigate the in vitro PAFE on 20 C. dubliniensis isolates following exposure to nystatin. In addition, the impact of nystatin-induced PAFE on adhesion to BEC, GT formation and relative CSH of C. dubliniensis isolates were also evaluated. After determining the minimum inhibitory concentration (MIC) of nystatin, C. dubliniensis isolates were exposed to sublethal concentrations of nystatin for 1 h. Following this exposure, the drug was removed and PAFE, adhesion to BEC, GT formation and relative CSH were determined by a previously described turbidometric method, adhesion assay, germ tube induction assay and biphasic aqueous-hydrocarbon assay respectively. MIC (μg/ml) of C. dubliniensis isolates to nystatin ranged from 0.09 to 0.78. The nystatin-induced mean PAFE (hours) on C. dubliniensis isolates was 2.17. Compared with the controls, exposure to nystatin suppressed the ability of C. dubliniensis isolates to adhere BEC, GT formation and relative CSH by a mean percentage reduction of 74.45% (P < 0.0001), 95.92% (P < 0.0001) and 34.81 (P < 0.05) respectively. Hence, brief exposure of C. dubliniensis isolates to nystatin would continue to wield an antifungal effect by suppressing growth as well as its adhesion attributes.

Microbiota–Gut–Brain Axis: Yeast Species Isolated from Stool Samples of Children with Suspected or Diagnosed Autism Spectrum Disorders and In Vitro Susceptibility Against Nystatin and Fluconazole

“…Since nystatin was dissolved in DMSO and absolute ethanol, equivalent amounts of the later chemicals were tested initially as done in previous studies using the same isolates to ascertain whether they had an effect on the isolates tested. The minute volumes of the chemicals used did not have any effect on yeast survival/growth when compared with the controls [16,17,20,21].…”

Comparison of anti-Candida albicans activities of halogenomethylsulfonyl derivatives

“…virulence factors was demonstrated for nystatin (Ellepola et al, 2014). The carryover effect of sulfone following its removal was minimal due to washing and centrifugation procedures which were shown to reduce agents concentration by 10,000-folds (Ellepola et al, 2014). Whereas, viable counts of the control and treated samples performed each time following sulfone removal showed no significant difference in cells growth.…”

“…Previously, PAFE impact on Candida spp. virulence factors was demonstrated for nystatin (Ellepola et al, 2014). The carryover effect of sulfone following its removal was minimal due to washing and centrifugation procedures which were shown to reduce agents concentration by 10,000-folds (Ellepola et al, 2014).…”

“…Following this limited exposure, Compound no. (7) was removed according to previously described procedure (Ellepola et al, 2014). The Candida cells were washed, resuspended in 2,000 ll of RPMI and used for tissue infection.…”

“…It has been demonstrated that virulence factors of C. albicans were significantly reduced after limited or transient exposure to subcidal concentrations of antifungal agents (Ellepola et al, 2014). The inhibition of SAP4-6 involved in C. albicans' morphogenesis and adhesion process (Naglik et al, 2008;Sardi et al, 2013;Tsai et al, 2013) represents a promising strategy for the design of new agents with effective antifungal abilities targeting Candida spp.…”