Chondroitin and Keratin Sulfate
- two major glycosaminoglycans w/ in cartilage ground substance consist of chondroitin sulfate and keratan sulfate;
- both of these substances are covalently attached to the core protein of proteoglycan;
- their concentration and distribution w/ in matrix vary considerably according to age, type of cartilage, & morphological location within
- ratio of chondroitin sulfate to keratin sulfate:
- infant: 12 to 1
- adult: 2 to 1
- osteoarthritis: 10 to 1
- chondroitin sulfate:
- N-acetyl galactosamine alternates w/ glucuronic acid to form disaccharide repeating unit of polymer;
- chondroitin sulfate consists of a chain of about 40 repeating units of N-acetyl chondrosine sulfate w/ about about 80 anionic charges;
- there are about 100 chondroitin sulfate glycosaminoglycan chains per proteoglycan subunit;
- chondroitin sulfate is the most prevalent of the glycoaminoglycan in cartilage:
- concentration of chondroitin-4 sulfate steadily decreases w/ age;
- chondroitin-6 sulfate concentration increases w/ older age;
- keratan sulfate:
- disaccharide repeating unit consisting of N-acetyl glucosamine alternating w/ galactose;
- keratan sulfate has variable chain length & variable degree of sulfonation;
- present in low levels in fetal & newborn cartilage;
- concentration rises w/ maturation upto 55% of total glycosaminoglycan content of the tissue;
- of note, Morquio's Syndrome is a disorder characterized by excessive accumulation of keratin sulfate in the tissues
Synthesis of chondrocytic keratan sulphate-containing proteoglycans by human chondrosarcoma cells in long-term cell culture.
Effect of hyaluronic acid/chondroitin sulfate on healing of full-thickness tendon lacerations in rabbits.
Characterization of aggregating proteoglycans from the proliferative, maturing, hypertrophic, and calcifying zones of the cartilaginous physis.
Original Text by Clifford R. Wheeless, III, MD.
Last updated by Data Trace Staff on Friday, June 1, 2012 11:10 am