Utilização de extrato hidroalcóolico e óleo essencial de Origanum vulgare com associações no tratamento da esporotricose experimental por Sporothrix brasiliensis

Abstract

The search for new drugs with antimicrobial action has been extensively studied especially with vegetal extracts, however, the research of their action against fungi is still scarce. Among the mycoses of public health importance, sporotrichosis has emerged in recent years as an important zoonotic disease in large urban centers, affecting cats, dogs and humans. The treatment of this mycosis is carried out with daily administration of antifungals, especially itraconazole, which is considered the drug of choice for both animals and humans. However, the commercially available active principles with action in the fungi of the Sporothrix schenckii complex are restricted. In this sense, there is a need for other therapeutic options for the treatment of sporotrichosis. Thus, the in vitro activity of plants demonstrated by preliminary studies with isolates of the Sporothrix schenckii complex stimulated the realization of the present study in order to determine the in vivo activity of the vegetal extracts of Origanum vulgare for the treatment of experimental cutaneous sporotrichosis. For this, 60 male Wistar rats were divided into 6 experimental groups inoculated with S. brasiliensis for the development of cutaneous sporotrichosis and submitted to 30 days of treatment with itraconazole, O. vulgare essential oil, hydroalcoholic extract of O. vulgare, association of the oil with itraconazole, association of the extract with itraconazole and a control group treated only with the vehicle. During the 30 days, the animals were evaluated weekly and 2 animals per group were euthanized for the collection of material to analyze the development of the disease and the evolution of the different treatments. At the end of the 30 days, the remaining animals from each group were euthanized and also had biological materials collected for the analyzes. At all necropsies, samples of liver, kidney, spleen, testis, inoculation point and regional lymph node were collected, as well as blood samples. As results obtained, only the animals belonging to the ITRA and CONT groups did not show complete disappearance of the clinical signs observed at the end of the 30 days of treatment, it was also possible to observe that the animals belonging to the groups treated with the hydroalcoholic extract of O. vulgare and with the essential oil of O. vulgare did not present any microscopic changes in the kidneys, liver and spleen throughout the experiment, thus indicating a possible effect of this plant on the spread of the disease. Sporothrix brasiliensis was retroisolated from the regional lymph node of all animals of all groups at the four necropsies performed. Analyzes of oxidative stress revealed no difference in their levels in any of the groups evaluated. The study evaluating the action of oil and extract may determine that both act at the ergosterol level of the fungus membrane.