a carbohydrate-protein polymer containing 70 to 80 percent carbohydrates. Most extensively studied have been the various types of acid mucopolysaccharides in connective tissue, in the synovia of the joints, and in the vitreous body of the eye.
The major types of mucopolysaccharides are hyaluronic acid, heparin, chondroitin sulfuric acids, and keratosulfate (found in cartilage and cornea). The carbohydrate portion of acid mucopolysaccharides is a linear polysaccharide consisting of periodically repeating units with N-sulfoaminosugar or N-acetylaminosugar residues (D-glucosamine or D-galactosamine) and uronic acid. The sulfuric acid residues in sulfate mucopolysaccharides are bound to the hydroxyl groups of monosaccharide components. Acid mucopolysaccharides differ widely in molecular weight, in binding energy of the components, and in functional properties.
Owing to their capacity to bind and hold water, acid mucopolysaccharides serve as a natural lubricant in the joints and impart elasticity to connective tissue. As a component of cartilage and ligaments, mucopolysaccharides are involved in support and motor functions. They also have bactericidal properties.
With aging, the composition of the mucopolysaccharides in connective tissue changes. Dysfunction in the mucopolysaccharide metabolism leads to a change in the composition of connective tissue and of the body fluids, resulting in diseases such as collagenosis, mucopolysaccharidosis, and rheumatism.
N. D. GABRIELIAN