Estudo do efeito gastroprotetor e mecanismo de ação do extrato etanólico de sementes de Triplaris gardneriana Wedd.

Abstract

The botanical species Triplaris gardneriana Wedd (Poligonaceae), known in Portuguese as Pajeú, belonging to the caatinga biome and presents in its seeds phenolic compounds with proven antioxidant capacity. Antioxidants can help in the treatment of several diseases related to oxidative stress, such as neurodegenerative diseases and inflammatory processes. This study aims to obtain an ethanol extract from the seeds of T. gardneriana (EETg), evaluate its chemical composition, antioxidant activity, gastroprotective effect and study the mechanisms of gastroprotective action in in vivo models. Quantitative data were described as means, and analysis of variance (ANOVA) was performed to compare the results. The results of total phenols and flavonoids in the samples showed values of 82.17 and 35.92 μg/mg, respectively. In the gastroprotection study, EETg at oral doses of 25, 50 and 100 mg/kg prevented lesions in 43.3; 60.3 and 75.4%, respectively, compared to the positive control. The lowest concentration that managed to reduce the lesion area and MDA levels at the same time was the dose of 50 mg / kg, which was established as the most suitable to be used for tests to clarify the mechanism of action of gastroprotection. These tests showed that the protective effect of EETg was significantly reduced in the presence of indomentacin and L-NAME, used as antagonists of prostaglandins and nitric oxide, respectively. The docking simulations suggested, according to the free energies of binding and molecular interactions, that the phenolic compounds could interact with the cyclooxygenases (COX-1 and COX-2) and nitric oxide synthase (iNOS), which confirms the involvement of prostaglandins and nitric oxide in the mechanism of action. Therefore, EETg may act as a gastroprotective substance, as its potential against gastric ulcers was very promising.