Abstract

The study aimed to investigate the antioxidant and immunomodulating activities of ethanolic extract from sapwood of Astronium fraxinifolium (EEAF) on LPS-stimulated RAW 264.7 cells. The constituents of the EEAF was analyzed by high performance liquid chromatography (HPLC). Antioxidant activity of EEAF was evaluated by its capacity of inhibiting the production of free radical DPPH and ABTS. For the analysis of its immunomodulatory properties, NO, TNF-α and TGF-β levels were determined in supernatants from LPS-stimulated RAW 264.7 cells after treatment with the EEAF at different concentrations. Expression for mRNA of COX-2 and iNOS, and detection of COX-2 protein were also analyzed. Caffeic acid, quercetin, followed by orientin and ρ-coumaric acid, were identified in the extract by the HPLC technique. The EEAF showed poor antioxidant activity when compared to the reference standard. Nitric oxide, expression of COX-2 mRNA and COX-2 protein were found in high levels when LPS-stimulated cells were treated with the EEAF. Moreover, increased levels of TNF-α and low secretion of TGF-β were demonstrated in supernatants from LPS-stimulated cells treated with EEAF at different concentrations. In opposition to many different types of medicinal plants, the EEAF demonstrated a powerful pro-inflammatory capacity.

Key words: Astronium fraxinifolium; Inflammatory mediators; RAW 264.7 cells, LPS; Inflammation