[The significance of proteoglycans in several diseases]

A prominent feature in several diseases is the accumulation of connective tissue. The ultimate result of high levels of extracellular matrix is organ failure and death, evident in diseases such as liver fibrosis, diabetes and amyloidosis. Among the extracellular matrix components, proteoglycans play a basic role in several pathological conditions. In the development of atherosclerosis they provide an anchor for lipoprotein lipase on the endothelial wall, sequester lipoproteins in the subendothelial matrix and present lipoproteins to macrophages. In diabetes these proteoglycans have a lower charge, such that the network has a reduced capacity to retain negatively charged proteins. In fibrosis and amyloidosis the synthesis of proteoglycans and matrix is increased and large amounts are deposited at the expense of tissue-specific cells. Some of the conditions mentioned can be ameliorated by changes in the diet.