Glycosaminoglycans, airways inflammation and bronchial hyperresponsiveness

Glycosaminoglycans (GAGs) are large, polyanionic molecules expressed throughout the body. The GAG heparin, co-released with histamine, is synthesised by and stored exclusively in mast cells, whereas the closely related molecule heparan sulphate is expressed, as part of a proteoglycan, on cell surfaces and throughout tissue matrices. These molecules are increasingly thought to play a role in regulation of the inflammatory response and heparin, for many years, has been considered to hold potential in the treatment of diseases such as asthma. Heparin and related molecules have been found to exert antiinflammatory effects in a wide range of in vitro assays, animal models and, indeed, human patients. Moreover, the results of studies carried out to date indicate that the antiinflammatory activities of heparin are dissociable from its well-established anticoagulant nature, suggesting that the separation of these characteristics could yield novel antiinflammatory drugs which may be useful in the future treatment of diseases such as asthma