ANTIANGIOGENIC ACTIVITY OF HYDROETHANOLIC EXTRACTS OF ASTRONIUM SP

Angiogenesis and tumor metastasis are functionally related processes, because both involve pathophysiological steps such as cell motility, tissue proteolysis and cellular proliferation, leading to the formation of new vessels from pre-existing vessels. Thus, plant species have shown promising source of compounds that can help to inhibit the formation of new vessels < sup > 1 < /sup > . Among these plants, Astronium sp is a neotropical genus of arboreal species typical of Brazil’s north and northeast savanna. The species Astronium urundeuva (aroeira-do-sertão), Astronium graveolens (guaritá) and Astronium fraxinifolium (Gonçalo-alves) are popularly used as anti-inflammatory, antimicrobial, anti-ulcerogenic and healing agents < sup > 2 < /sup > . In order to evaluate the in vivo antiangiogenic activity, we used of healthy and normal zebrafish ( Danio rerio ) embryos, individually distributed to each well of 96 wells microplate < sup > 3 < /sup > . After that, 100 µL of Astronium sp extracts (25 µg/mL) was added and the microplate was incubated for 72 hpf (hours post-fertilization). DMSO was used at a concentration of 0.2% v/v as vehicle control and 2-methoxyestradiol (2ME) was used as standard antiangiogenic substance (30 µg/mL). The embryos were stained using the quantitative endogenous alkaline phosphatase (EAP) assay and the optical density (OD) of the final soluble product was measured at 405 nm using a microplate reader. For staining blood vessels it was used NBT/BCIP (nitro-blue tetrazolium and 5-bromo-4-chloro-3'-indolyl phosphate p-toluidine salt) and after that, embryos were examined by optical microscopy checking the vitality or morphological defects. The extracts of Astronium sp showed antiangiogenic potential at a concentration of 25 µg/mL. The extract with the highest antiangiogenic activity was the leaves of A. fraxinifolium inhibiting 30% of the vessel formation. The stem extract of this same species showed a inhibition of 22.6% while the extract A. urundeuva leaves presented a pro-angiogenic activity. It was concluded that the extracts of Astronium sp have constituents capable of preventing the formation of blood vessels.