Aging: Present Status of Our Chemical Knowledge

Joint capsule collagen. Analysis by the study of intra-articular pressure during joint distension. Measurements in the knees of control subjects and patients with rheumatoid arthritis and Ehlers-Danlos syndrome.

“…Increase in the number of cross-linkages makes the collagen chemically more stable and physically less easy to stretch. Keech (1955) found that digestion of dermal collagen by a collagenase fell with the subject's age, and Bjorksten (1962), Verzar (1963, and Bailey (1969) demonstrated an increase in the cross-linkages in the collagen molecule with age. In lathyrism collagen fibres are fragile and easily broken, but the microscopic appearances of the collagen appear to be unaffected; this change in physical properties is due to cleavage of the crosslinkages (Levene, 1961;Bailey, 1969).…”

The Influence of Ageing on the in vivo Elasticity of Human Skin

“…There is considerable evidence for an increase in intramolecular cross-linkages in collagen with age [Bjorksten, 1962]. In an earlier contribution to this symposium it has been shown that tnfer-molecular cross-links occur, which may be even more important in increasing the stability of the collagen molecule with age than the intra-molecular ones [Bailey, 1968].…”

Chemical Mechanisms Underlying the Biological Mechanisms of the Aging Process

“…The numerous reports on indirect evidence of cross‐linkage by progressively increasing molecular weight and decreasing swellability and elasticity have been previously summarized (12) and therefore need not be repeated.…”