Glycosaminoglycan-degrading enzymes in the varicose vein wall.

AIM: Mechanical properties of the vein wall are determined by extracellular matrix components, including glycosaminoglycans (GAGs). The aim of the study was to evaluate the activity of enzymes involved in GAGs degradation pathway in the wall of varicose veins and varicose veins complicated by thrombophlebitis, when compared to the wall of normal ones. METHODS: Normal, varicose veins and varicose veins complicated by thrombophlebitis were collected during surgical treatment of 10 patients. Activities of endoglycosidases, sulphatases and exoglycosidases were assessed according to colorimetric methods. RESULTS: Activities of neutral endoglycosidases degrading chondroitin-4-sulphate (C4S) and heparan sulphate (HS) were decreased, whereas activities of neutral endoglycosidases degrading dermatan sulphate and hyaluronic acid were increased in varicose veins and varicose veins complicated by thrombophlebitis. Activities of acidic endoglycosidases degrading C4S and HS were decreased in varicose veins and varicose veins complicated by thrombophlebitis, whereas activity of acidic endoglycosidases degrading chondroitin-6-sulphate was decreased only in varicose veins complicated by thrombophlebitis. Furthermore increased activities of arylosulphatase B, beta-N-acetylhexosaminidase and alpha-L-iduronidase were demonstrated in varicose veins, as well as in varicose veins complicated by thrombophlebitis. CONCLUSIONS: Changed activities of GAGs-degrading enzymes may contribute to previously reported changes in the content and molecular differentiation of GAGs in the wall of varicose veins that may play a role in the disease pathogenesis.