Age-Dependent Change in the Gel-Electrophoretic Pattern of Proteoglycans of Human Growth Cartilage

Abstract

The gel-electrophoretic pattern of dissociated proteoglycans was studied in 7 fetuses, 5 premature newborns, 4 term newborns, 5 infants and 5 children. The tibial growth cartilage was extracted with 4 M guanidinium chloride. After dialysis against 8 M urea at pH 7 the proteoglycans were obtained by ion chromatography in urea on DEAE cellulose and submitted to gel electrophoresis on polyacrylamide agarose gels. Gel electrophoresis of proteoglycans showed a different pattern in fetuses from that found in children. The change occurs in the first months of extrauterine life.

Proteoglycans: Their structure, interactions and molecular organization in cartilage

“…Although the present model of proteoglycan structure provides a rational framework that accounts for many features, it cannot be taken as complete or final. For example, the separation of proteoglycan monomer preparations from a variety of cartilaginous sources into two or three discrete components on electrophoresis (Stanescu et al, 1973(Stanescu et al, , 1977Roughley & Mason, 1976) is not predicted from the model, and the explanation for it is unclear, but it may indicate that there are additional features that have yet to be described. Small proportions of non-aggregating proteoglycan that appear to be structurally unrelated to the aggregating type have also been reported (Heineglrd & Hascall, 1979).…”

“…4). The proteoglycans of different cartilages may be based on polypeptides to which variable numbers and sizes of glycosaminoglycan chains and oligosaccharides have been attached (Stevens et al, 1979). For example, some of the shorter 0-glycosidically linked oligosaccharides may reflect abortive keratan sulphate chains and may be the sites at which full-length keratan sulphate chains are synthesized on the proteoglycans of older tissues.…”

Proteoglycan populations of baboon (Papio papio) articular cartilage. Gel-electrophoretic analysis of fractions obtained by densitygradient centrifugation and by sequential extraction

“…Previously dissociated articular-cartilage proteoglycans purified by DEAE-cellulose chromatography were heterogeneous when examined by gel electrophoresis (Stanescu et al, 1973;Stanescu & Maroteaux, 1975a). Equilibrium-density-gradient centrifugation (Sajdera & Hascall, 1969;Hascall & Sajdera, 1969) has been widely used for purification and fractionation of cartilage proteoglycans, and sequential extraction (Tsiganos & Muir, 1969;Hardingham & Muir, 1974) has also been used to obtain different fractions of proteoglycan.…”

“…Its migration was not identical in all the species studied. (Stanescu et al, 1973(Stanescu et al, , 1975. Pathological changes in cartilage proteoglycan populations were observed in the articular cartilage of lame pigs (Simiinek & Muir, 1972b) and in the growth cartilage of some human chondrodysplasias (Stanescu & Maroteaux, 1975b).…”