Atividade do óleo de copaíba no modelo de asma alérgica experimental induzido por ovalbumina em camundongos BALB/c

Abstract

Asthma is an inflammatory allergic disease of the airways, considered a public health problem, capable of causing significant suffering and high costs for families and for health systems. Problems related to the difficulty of access to treatment besides low adherence and risk of low responsiveness in certain cases, justify the research of new compounds with anti-inflammatory and immunomodulatory properties, including accessible and low cost. Copaiba oil (OC) is a renewable alternative of natural origin widely used in folk medicine with anti-inflammatory activity but not yet studied for the treatment of this disease. Through the model of allergic asthma with ovalbumin (OVA), which allows the induction of the main T helper cells (TH) responses involved in this inflammation, we investigated the effects of OC in BALB/c mice. The essential oil investigated had its composition verified by gas chromatography with flame ionization detector (CG-FID) and gas chromatography coupled to the mass spectrometer (CG-MS). Tests for hepatic, renal, or glycemic effects toxicity were performed in the mice using OC by gavage at the dosages to be used in the investigation, 50 mg/kg and 100 mg/kg. After the induction of allergic asthma, the anti-inflammatory potential of OC was evaluated by the total and differential count of the inflammatory cells in the tracheal lavage, nitric oxide (NO) production and concentration of cytokines related to the pathogenesis of allergic asthma, interleukin-4 (IL-4), IL-17, interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α) in the tracheal lavage and pulmonary maceration. Histopathological and histomorphometric analysis were also performed on pulmonary samples. The analysis of the results showed that the OC treatment significantly attenuated the inflammatory signals, reducing the count of inflammatory cells present in the tracheal lavage, suppressing NO production and reducing the T cell-mediated response involved in the disease. In the treated animals there was also a reduction of the inflammatory infiltrate in the lung tissue, with reduction of the alveolar parenchyma area. It was not possible, however, to correlate a dose-response effect due to the fact that statistical differences between the two doses (50 and 100 mg/kg) were not demonstrated in most of the results. Based on the above, this study concluded that OC is a promising substance in the treatment of asthma, and further studies are needed to fully elucidate its effect on the body.