What else can 'Heparin' do?

This review article begins by discussing the molecular basis of the blood anticoagulant effect of heparin and some species of heparan sulphate (HS). A highly specific pentasaccharide sequence, containing a glucosamine 3-O-sulphate group, is a key structural element for this action. The biosynthesis of heparin and HS is outlined. Different types of HS proteoglycans exist. Analysis of HS preparations from different mammalian organs has indicated that the structural variability of the polysaccharide is due to regulated polymer modification. In addition to antithrombin, HS chains bind a very large number of other proteins in vivo. Such binding often appears to depend on the presence of specific sequences of different monosaccharide building-blocks and has diverse implications. Many physiological and pathological processes in the mammalian body appear to be influenced or regulated by HS proteoglycans. For example, the proper assembly of HS chains is believed to play an important role in normal embryonic and mammalian development. Diseases such as diabetes, amyloidosis and Alzheimer's may be associated with changes in HS structure. Finally, the possibilities and strategies for developing drugs based on HS chemistry are discussed.