Topographic and Age-Dependent Distribution of the Glycosaminoglycans in Human Aorta

Publisher Website
Google Scholar
Abstract
The total glycosaminoglycan content decreases from 18.2 in the 2nd to 14.2 .mu.mol hexosamine per g dry wt in the 8th decade. This decrease becomes more pronounced, if the inorganic material (calcium phosphate), the proportion of which increases from 10 g/kg (2nd decade) to 140 g/kg (8th), is included in the dry weights; the total glycosaminoglycan content, then decreases from 18.0 (2nd to 12.4 .mu.mol per g dry wt in the 8th decade. The glycosaminoglycans in human aortae between the 2nd and the 8th decade of age consist chiefly of chondroitin 4-sulfate (20-30%), chondroitin 6-sulfate (20-29%) and heparan sulfate (18-27%), followed by dermatan sulfate (13-17%), hyaluronate (5-15%), keratan sulfate (4-8%) and chondroitin (1-3%). The concentrations of chondroitin 6-sulfate and heparan sulfate decrease from the 2nd to the 8th decade, whereas the concentration and relative proportion of keratan sulfate increase especially from the 6th to the 8th decade. With regard to the longitudinal distributions of the glycosaminoglycans in human aorta, the 4th and the 8th decade of age were studied. The total glycosaminoglycan concentration of the younger group exhibits an increase from proximal to distal regions, whereas in the older group the glycosaminoglycan concentration remains nearly constant in all segments, being higher in the aortic arch and lower in the 2 distal regions than in the corresponding regions of younger aorta. In the region of the aortic arch the concentration and the relative proportion of hyaluronate, dermatan sulfate and chondroitin 4-sulfate decrease on aging, while those of heparan sulfate, keratan sulfate and chondroitin 6-sulfate increase. In the middle region of human aorta only keratan sulfate and chondroitin 4-sulfate increase with age. In the region of the bifurcatio, where the highest deposition of inorganic material was found, contents and relative proportions of hyaluronate, keratan sulfate and dermatan sulfate increase during aging, when those of heparan sulfate and the chondroitin sulfates, especially chondroitin 6-sulfate, decrease.