Proteoglycans and the extracellular matrix in amyloidosis

Amyloidosis comprises numerous diseases that are characterized by the deposition of insoluble amyloid, fibrils in the extracellular matrix in one or more of virtually any organ and tissue of the boat: The general nature of amyloid deposits is still not completely defined, however, the presence of fibrillar structures is unquestioned, and the fibrils themselves are derived from proteins. The nature of the nonfibrillar constituents of amyloid deposits is still obscure, but it is becoming evident that proteins such as the amyloid P component, apoE and components derived from the extracellular matrix itself especially basement membranes, seem to represent ubiquitous components of amyloid deposits, irrespective of the biochemical nature of the fibril-forming protein. The extracellular matrix components found in amyloid include proteoglycans, glycosaminoglycans, glycoproteins and extracellular matrix growth factors. Here, proteoglycans and the extracellular matrix, as they relate to amyloidosis, are reviewed.