Showing papers on "Keratan sulfate published in 1971"

The Glycosaminoglycans of Normal and Arthritic Cartilage

Abstract: The cartilages from the hip joints of 13 normal and 15 osteoarthritic humans were analyzed for glycosaminoglycan content and distribution. The GAGs were separated by elution with CPC on a short cellulose column by the technique of Svejcar and Robertson after digestion of the tissue with pronase and papain. The eluates were identified by a variety of methods including determination of molar ratios, N-acetyl-hexosamine determinations after hyaluronidase treatment and thin-layer chromatography of unhydrolyzed and hydrolyzed GAGs. From the data obtained, it was demonstrated that cartilage from arthritic patients showed a significant increase in the concentration of chondroitin 4-sulfate and a significant decrease in keratan sulfate, with only slight changes in the total amount of GAG present. Calculations of the molar ratios showed variation in the sulfation with chondroitin 4-sulfate appearing in the "supersulfated" state in the arthritic cartilage. The data lead to speculation regarding the process of osteoarthritis, and it is concluded that the changes seen are more likely to represent an altered pattern of synthesis rather than selective degradation. Since the changes suggest a younger cartilage, a theory is advanced that the chondrocyte responds to the chronic stress of osteoarthritis by modulation to a chondroblastic phase.

Mucopolysaccharide and Protein—Polysaccharide of a Transplantable Rat Chondrosarcoma

Abstract: Two mucopolysaccharides, chondroitin 4-sulfate (97.8%) and hyaluronic acid (1.2%), were isolated after exhaustive proteolysis of a transplantable chondrosarcoma of the rat. The chondroitin 4-sulfate was fractionated into three fractions of varying degrees of sulfation and chain length. Keratan sulfate and chondroitin 6-sulfate were absent. Extraction of the fresh tumor gave two protein—polysaccharides of similar carbohydrate composition, one soluble in 0.5 M NaCl, the other insoluble. The latter was solubilized in 4 M guanidine·HCl. A dialyzable fraction from the 4 M guanidine solution may be responsible for the insolubility. Both protein—polysaccharides were antigenic and cross-reacted with similar fractions of bovine and human cartilage.

Glycosaminoglycans in Human Comeal Buttons Removed at Keratoplasty

Abstract: Microfractionation and analysis of individual human corneal buttons were performed on both normal corneas and on corneas removed at keratoplasty from eyes with keratoconus or swollen, opaque corneas. Keratoconus buttons were found to have a relative increase in the glucosaminoglycan (keratan sulfate) fraction and a significant decrease in the galactosaminoglycan (chon-droitin sulfate) fraction. There was decreased sulfation of galactosaminoglycans in keratoconus buttons. Both the glucosamino glycans and the galactosaminoglycans were decreased in some swollen opaque corneas. In these corneas a highly sulfated glycosaminoglycan was recovered not present in normal corneas, which was comparable in many ways to dermatan sulfate.

Histochemical Localization of Acid Glycosaminoglycans in Human Articular Cartilage

Abstract: Fresh human articular cartilage from patients, 23 to 79 years of age, has been examined histochemically for its distribution of acid glycosaminoglycans The alcian blue stain with different salt concentration enabled us to localize chondroi-tin sulfate and keratan sulfate in the matrix and in the halos Young cartilage had a fairly even distribution of chondroitin sulfate, and only the matrix of the deepest zone stained less intensely With increasing age the intensity of the chondroitin sulfate stain decreased and the tendency for a lack of matrix stain in the deeper layer was more pronounced in old than in young cartilage In young cartilage, keratan sulfate is exclusively found in the matrix; the halos and their immediate surroundings are unstained With increasing age and distance from the surface this pattern is less marked and keratan sulfate may be found even inside the halos In the examined material four of the cartilages, here referred to as slightly arthrotic cartilage, showed an acid glycosaminoglycan distribution which differed from normal as well as from arthrotic cartilage In these cases the chondroitin sulfate concentration was high in the halos while the matrix itself was unstained The keratan sulfate distribution was even more deviating in showing an unstained matrix and a ring formation around the secondary halos in the upper half, and intensely stained halos in the lower half of the section