Efeito dose-dependente da terapia fotodinâmica antimicrobiana sobre parâmetros oxidativos e histológicos na língua de ratos

Abstract

Antimicrobial Photodynamic Therapy (aPDT) is defined as a photochemical reaction used in order to cause destruction of microorganisms. This therapy has been widely used in dentistry, but there are two important limitations of its use: (i) there are no established security protocols, (ii) little quantity of toxicity studies regarding the doses for therapeutic varied. Accordingly, different aPDT doses were administered in the tongue of healthy rats and oxidative and histological tissue changes were investigated in order to estimate the tissue damage. Forty male Wistar rats (± 250g) were randomly divided into eight experimental groups (n = 5): control group (CG group), which was not submitted to aPDT and the other groups tested with the following light energy doses of doses 18J / cm2 (L18 group), 24J / cm2 (L24 group), 30J / cm2 (L30 group), 70J / cm2 (L70 group), 122J / cm2 (L122 group), 275J / cm2 (L275 group) and 400J / cm2 ( L400) group. Six hours after exposure to aPDT, the tongues of the animals were removed for biochemical analysis of oxidative stress parameters by measuring the levels of reactive oxygen species, lipid peroxidation levels and carbonylation protein also the activities of catalase (CAT), reduced glutathione (GSH) levels tongue and histological analysis of inflammatory infiltrate. The results suggest that there is a security window between different doses of aPDT, and this may be employed safely without damaging healthy tissue lingual.