Heparin and a cyclic octaphenol-octasulfonic acid (GL-522-Y-1) bind with high affinity to a 47-kDa protein from vascular endothelial cell surface and stimulate the synthesis and structural changes of heparan sulfate proteoglycan

Abstract

The effect of a cyclic octaphenol-octasulfonic acid (GL-522-Y-1), upon the synthesis of a heparan sulfate proteoglycan synthesized by endothelial cells (rabbit aorta and human umbilical vein) were studied. the cells were exposed to the compounds at various concentrations for different periods of time and the synthesized heparan sulfates analyzed by a combination of agarose gel electrophoresis and enzymatic degradation. the GL-522-Y-1, like heparin, change the sulfation pattern and stimulate two- to three-fold the synthesis of heparan sulfate proteoglycan secreted by rabbit and human endothelial cells in culture. GL-522-Y-1, besides being 100 times more active than heparin, also produces a significant enhancement of cell surface heparan sulfate in human vein endothelial cells. the effect of GL-522-Y-1 is completely abolished by methylation or acetylation of its free hydroxyl groups. Both heparin and GL-522-Y-1 have high affinity for a 47-kDa protein present at the surface of endothelial cells. These and other results lead us to speculate that the antithrombotic activity of heparin and GL522 in vivo could be related, at least in part, to the increased production of the heparan sulfate proteoglycan by endothelial cells. (C) 2001 Elsevier B.V. All rights reserved.