Anti-inflammatory and anti-allergic activity of the methanolic extract from Annona sylvatica (Annonaceae)
Annona sylvatica (Annonaceae) is a common medicinal plant used in folk medicine for fever and cough; it is found in several Brazilian states, including Mato Grosso do Sul. The local population uses A. sylvatica leaves for treating fever and cough; however, how this medicinal plant affects the patients is little understood. We evaluated the anti-inflammatory and anti-allergic properties of a methanolic extract of A. sylvatica (MEAS) leaves in mouse models of inflammation and allergy. The study employed male C57bL/6 mice for allergy models and male Swiss mice for the inflammation study. Oral treatments with MEAS (30 to 150 mg/kg) significantly inhibited the carrageenan-induced leukocyte migration and protein extravasation to the cavity in an air pouch model. In the allergic animal models, oral treatment with MEAS (150 mg/kg) significantly reduced histamine- and ovalbumin (OVA)-induced paw edema. Moreover, in the OVA-induced allergic lung inflammation model, oral treatment with MEAS (150 mg/kg) significantly inhibited neutrophil, eosinophil, and mononuclear cells migration to the lung. Pretreatment of neutrophils with MEAS (3, 150, 300 µg/mL) significantly reduced neutrophil chemotaxis induced by N-Formyl-Met-Leu-Ph (fMLP) and complement 5a (C5a, in a concentration-dependent manner. We conclude that A. sylvatica has anti-inflammatory and anti-allergic properties. Flavonoids and acetogenins, compounds found in the MEAS, could be responsible for these anti-inflammatory and anti-allergic effects.