Utilização de formas farmacêuticas tópicas contendo extratos vegetais no tratamento de otite externa experimentalmente induzida em modelo murino

Abstract

Otitis externa is classified as an acute or chronic inflammation of the external auditory canal. It is among the most frequent diseases in companion animal medicine, being reported on approximately 20% of dogs. The objectives of this study were to report a case of chronic otitis externa in a dog, with the development of neoplastic mass. And also, to evaluate the effect of LCFO-1001 and 1002 on the experimentally induced external otitis in murine model both containing extracts vegetables of Bixa orellana L. and Triticum aestivum in the treatment of experimentally induced external otitis in a murine model. The patient addressed in the case report was a dog with a history of otitis for more than 8 months, not responsive to antimicrobial treatment. Due to the severity of its otologic disease and the presence of a tumor nodule adhered to the tympanic bulla, two surgical procedures were performed, the last one being the total removal of the auditory canal. After recovery from this surgical procedure, the patient showed no signs of pain, edema, erythema or excessive secretion from the surgical wound. For the evaluation of plant extracts, 96 female rats (Rattus norvegicus) of the Wistar lineage were used, which had otitis induced by sedation and previous anesthesia followed by inoculation of the ears with 80μL of 5% Chroton oil in acetone, and one hour after, 100 μL solution containing the infectious agent (Staphylococcus aureus). The animals were randomly distributed into groups of 24 (n=48 ears/group) according to the treatment: GI: LCFO-1001, GII: LCFO-1002, GIII: commercial otological solution (positive control), GIV: 0.9% NaCl (negative control). The animals were treated for up to seven days every 24 hours, and in two (D2), four (D40) and eight days (D8), eight animals per group were anesthetized, evaluated and euthanized by anesthetic overdose. Evaluation and classification were performed using scores of the clinical parameters: coloration, luminal diameter and effusion. Under the conditions of this study it is possible to conclude that total ablation conferred remission of clinical signs related to otitis. As well as the otological pharmaceutical formulations containing the oily and ethanolic extract of Bixa orellana L. and Triticum aestivum, obtained similar results to the conventional treatment in reducing the clinical signs associated with experimentally induced external otitis in the murine model. Being present as possible helpers in the treatment of external otitis although more studies are needed.