Age-related changes in glycosaminoglycan chains of nucleus pulposus proteoglycan of baboon vertebral discs

Age-related changes in the glycosaminoglycans of the large proteoglycan in the nucleus pulposus of baboon intervertebral discs were examined. The proteoglycans were separated by column chromatography from specimens of nucleus pulposus divided into three groups according to age. After enzymatic digestion, the glycosaminoglycan chains obtained from the proteoglycan were analyzed using HPLC and a biosensor. The glycosaminoglycans were composed mainly of chondroitin 6-sulfate. The molecular mass of the glycosaminoglycans decreased with age, but their sulfate content did not change. The affinities of the proteoglycan for various types of collagen were determined. There was increased binding to type IX collagen with aging. (C) 2001 Elsevier Science B.V. All rights reserved.