Changes in glycosaminoglycans and related proteoglycans in intrinsically aged human skin in vivo.

Glycosaminoglycans (GAGs) and proteoglycans (PGs) are involved in various structural functions and physiological regulations in the skin. To investigate the intrinsic ageing-dependent GAG and PG changes and their gender-specific difference, immunohistochemical stains of several GAGs and PGs were performed in sun-protected buttock skin tissues of young and old, male and female (total n = 32) human skin. Stains of alcian blue, hyaluronic acid (HA) and heparan sulphate were reduced in aged skin in both genders, whereas chondroitin sulphate stain was decreased only in female. Stains of HA synthase-2, CD44, CD44v3, syndecan-1 and decorin were decreased in aged skin in both genders, whereas perlecan stain was reduced only in female, and syndecan-4 stain did not change. Versican stain was increased in male aged skin, but not in female. Age- and gender-related changes in GAGs and PGs in intrinsically aged buttock skin elucidated in this study may play important roles in intrinsic skin ageing process.