Preclinical study of a cost-effective photodynamic therapy protocol for treating oral candidoses

Abstract

Oral candidoses affect a large number of persons worldwide and are associated with conditions such as immunosuppression, radiation therapy, smoking, oral hygiene, age, xerostomia and denture wearing. An important therapeutic approach for these infections consists in antifungal agents which can present adverse effects and result in resistance of pathogens. Within this context photodynamic therapy (PDT) is an interesting alternative capable of minimizing such limitations. PDT protocols can be more easily assimilated in clinical practice if they employ materials approved for dental use. Therefore, this study aims to evaluate PDT with erythrosine as a photosensitizer irradiated by a blue LED using a murine model. Forty mice will have candidosis induced on the tongue dorsum by means of immunosuppression and inoculation with Candida albicans. After the establishment of lesion, each mouse will receive one among four possible treatments: (L+E+) 5% erythrosine on mucosa followed by LED irradiation; (L-E-) saline solution only; (L+E-) saline followed by irradiation; and (L-E+) erythrosine. The same treatments will be applied in 12 candidosis-free mice in order of distinguishing possible adverse effects. The number of colony forming units of C. albicans will be quantified after treatment and mucosal samples will be subjected to a histological assessment of the degree of inflammation. Data will be compared by means of tests such as ANOVA and Kruskal-Wallis followed by post hoc comparisons (±=0,05). (AU)