ANTIANGIOGENIC EFFECT OF SULFATED AND NONSULFATED GLYCOSAMINOGLYCANS AND POLYSACCHARIDES IN THE CHICK-EMBRYO CHORIOALLANTOIC MEMBRANE

The inhibiting effect of sulphated and nonsulphated glycosaminoglycans and polysaccharides on the normal outgrowth of capillaries was tested in the chick embryo chorioallantoic membrane (CAM) with and without the presence of hydrocortisone. An antiangiogenic response to 50-mu-g of heparin and heparin sulphate (without hydrocortisone present) was observed in 38.8% and 23.1% of the CAMs, respectively, while the antiangiogenic response rate for dermatan sulphate, chondroitin sulphate A or C, hyaluronic acid and keratan sulphate was 15.9-0%. All sulphated homopolysaccharides tested were more effective than the naturally occurring glycosaminoglycans. Nonsulphated dextran and (methyl) cellulose had no antiangiogenic effect, while largely desulphated heparin retained such an effect. Hydrocortisone generally improved the antiangiogenic effect, a 100% response was obtained when it was combined with cellulose sulphate or fucoidan (polyfucose sulphate derived from marine algae), but the antiangiogenic effect of the largely desulphated heparin was unaffected by the presence of hydrocortisone. The results show that different polysulphated polysaccharides also have an antiangiogenic effect, without the addition of corticosteroids. The effect was apparently independent of their degree of sulphation, but the glycosidic structure may be of critical importance.