Anti-Inflammatory Effect of Anadenanthera Colubrina VAR. Cebil (Griseb.) Altschul in Experimental Elastase-Induced Pulmonary Emphysema in Rats

Ethnopharmacological relevance The use of medicinal plants has shown promise in the search for new pharmacological therapies for pulmonary emphysema. Anadenanthera colubrina, a species indigenous to the Caatinga biome in northeastern Brazil, is widely recognized and traditionally employed for the treatment of pulmonary diseases. Many studies corroborate popular knowledge about the medicinal applications of A. colubrina, demonstrating a remarkable variety of pharmacological properties, however, this medicinal plant stands out especially for its anti-inflammatory and antioxidant properties.Aim of the study The objective of this study was to investigate the anti-inflammatory potential of the crude hydroethanolic extract of A. colubrina var. cebil (Griseb.) Altschul in alterations caused by experimentally induced pulmonary emphysema in rats.Materials and methods The stem bark of the plant was collected in Pimenteiras-PI and extracted through maceration using 70% ethanol. A portion of the extract underwent phytochemical analyses using TLC and HPLC. For the pulmonary emphysema protocol, male 8-week-old Wistar rats weighing approximately ±200 g was utilized, following approval from the local ethics committee for animal experimentation (No. 718/2022). Pulmonary emphysema was induced through orotracheal instillation of elastase, and treatment with A. colubrina extract or dexamethasone occurred concomitantly with induction. Twenty-eight days after the initiation of the protocol, blood was collected, and plasma was used for cytokine measurement. Bronchoalveolar lavage (BAL) was performed for total and differential leukocyte count. After euthanasia of the animals, lung samples were processed for histological analysis, and markers of tissue oxidative stress were quantified. All data were subjected to normality analysis and subsequently underwent analysis of variance and Tukey's post-test, considering a significance level of p < 0.05.Results A significant reduction (p < 0.05) in neutrophilic inflammation was observed in the lungs of rats treated with the extract, as evidenced by cell presence in both the tissue and BAL. The extract also demonstrated pulmonary antioxidant activity, with a significant decrease (p < 0.05) in myeloperoxidase, malondialdehyde, and nitrite activities. TNFα, IL-1β, and IL-6 levels, as well as alveolar damage, were significantly reduced in animals treated with A. colubrina extract. Phytochemical analyses identified the presence of phenolic compounds and hydrolysable tannins in the A. colubrina extract. These substances possess anti-inflammatory and antioxidant properties, potentially explaining the observed beneficial effects of the extract.Conclusions The findings of this study underscore the potential of the hydroethanolic extract from the bark of Anadenanthera colubrina as a complementary therapeutic approach for emphysema treatment. The observed properties offer an optimistic perspective for the utilization of this medicinal plant in the development of therapies for managing pulmonary emphysema.