RESUMO

A low-molecular-weight (LMW) heterofucan (designated fucan B) was obtained from the brown seaweed, Spatoglossum schröederi, and its activity as an inhibitor of capillary-like tube formation by endothelial cells (ECs) was analyzed. Chemical, infrared and electrophoretic analyses confirmed the identity of fucan B. In contrast to other LMW fucans, fucan B (0.012-0.1 mg/mL) inhibited ECs capillary-like tube formation in a concentration-dependent manner. In addition, fucan B (0.01-0.05 mg/mL) did not affect ECs proliferation. Fucan B also inhibited ECs migration on a fibronectin-coated surface, but not on laminin- or collagen-coated surfaces. Biotinylated fucan B was used as a probe to identify its localization. Confocal microscopy experiments revealed that biotinylated fucan did not bind to the cell surface, but rather only to fibronectin. Our findings suggest that fucan B inhibits ECs capillary-like tube formation and migration by binding directly to fibronectin and blocking fibronectin sites recognized by cell surface ligands. However, further studies are needed to evaluate the in vivo effects of fucan B.

Assuntos

Anticoagulantes/química , Células Endoteliais/efeitos dos fármacos , Fibronectinas/metabolismo , Polissacarídeos/química , Animais , Anticoagulantes/farmacologia , Aorta/citologia , Aorta/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Cricetinae , Fibronectinas/química , Humanos , Peso Molecular , Phaeophyceae/química , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Ligação Proteica/efeitos dos fármacos , Alga Marinha/química