|2349 Nicotine and Biofilm Alters Candida albicans Resistance to Antifungal Agents|
P.A. SAMANT, University of Tennessee, Memphis, USA, and J.P. BABU, University of Tennessee, Memphis, USA|
Candida albicans has been recognized as an etiological agent of superficial and systemic disease of the oral cavity. The organism was shown to colonize the surfaces of denture acrylic material. Nicotine, a component of tobacco, was shown to enhance biofilm formation on denture material, but its influence on Candida albicans resistance to antifungal agents is unclear. Objective: Study the influence of nicotine and growth conditions on Candida albicans resistance to antifungal agents. Methods: Candida albicans ATCC 44505 was employed in this study. Nystatin and Amphotericin B were purchased from Sigma chemical Co. The biofilm Candida albicans were grown on methacrylate disks for 3 days. A suspension (107 cells per ml) of freshly cultured Candida albicans and Biofilm grown cells were treated for 8 hours with nicotine (400 ng/ml) or saline (control). Fungal cells were mixed with serial two-fold dilutions of the antifungal agents, and incubated for 6 hours. The cells were centrifuged, washed, and then incubated with XTT reagent for 2 hours and. the absorbance (490nm) of the supernatant was measured in an ELISA reader to determine their metabolic activity (MA). Results: Biofilm-grown Candida albicans and nicotine treated cells exhibited resistance to anti-fungal agents, compared to freshly grown cells. The data from XTT assay showed that 50% reduction in MA of freshly cultured cells required 50 Units (U) and 3.125 µg, while the same cells when treated with nicotine, required >250 U and 25 µg of Nystatin and Amphotericin B, respectively. Biofilm-grown cells required 250U of Amphotericin B, while those treated with nicotine required 1000U for 50% reduction in MA. Conclusion: The results show that nicotine treated and biofilm-grown Candida albicans are more resistant to antifungal agents used to treat denture stomatitis.
|Seq #251 - Periodontal Research Pathogenesis 4|
2:00 PM-4:00 PM, Friday, 11 March 2005 Baltimore Convention Center Exhibit Hall E-F