Evaluation of antiulcer activity from methanolic extract of Astronium urundeuva (Allemão) leaves

Abstract

Gastric ulcer is an infirmity that affects a significant number of persons and is regarded as one of the major cause of morbidity and mortality in the world. In Brazil this incidence is estimated to range from 1 to 20% of the population, considering that a great part of the this population don't have access to medicines commercially available used to treat disorders such as gastric ulcers and that this leads to the use of medicinal plants that in most part don't have theirs efficiency and safety verified by studies. With the approval of the the Política Nacional de Práticas Integrativas e Complementares (PNPIC) no Sistema Único de Saúde (SUS) that implements the use of medicinal plants and phytotherapics as a treatment option for diseases for primary health care, studies of medicinal plants and their popular uses gain importance in Brazil. Gastric ulcers are gastrointestinal disorders characterized by severe lesions of the stomach wall, usually developed from an imbalance between aggressive factors and cytoprotective factors of the gastrointestinal epithelium. The healing process is complex and highly regulated and results in the reestablishment of the surface epithelium, glandular structures, blood vessels and connective tissue of the damaged area. The epidermal growth factor (EGF), enzymes cyclooxygenase-1 and -2 (COX-1 and 2) and matrix metalloproteinase-2 and 9 (MMP-2 and 9) act in these processes degrading the collagen and amorphous fibronectins present in the affected area causing an epithelial remodeling in several ways. Previous studies performed in our laboratory confirmed the gastroprotective action of the methanol extract of the leaves of Astronium urundeuva at a dose of 250 mg / kg but there are no reports of its healing action on the gastric mucosa. These studies on the healing property of this species are essential to support the indication of this species as a potential phytotherapic remedy against gastric ulcers. Therefore, this proposal aims to evaluate the wound healing activity of hydroalcoholic extract of its leaves and to elucidate the mechanisms of action of the extract on healing the gastric mucosa through the study of factors and enzymes such as COX1, COX2, VEGF and matrix metalloproteinases 2 and 9 that are related to the restructuring of the injured mucosa. This project is a subproject of the thematic project Biota/FAPESP "Fitoterápicos padronizados como alvo para tratamento de doenças crônicas" from No 09/52237-9.