Biochemical composition and turnover of the extracellular matrix of the normal and degenerate intervertebral disc

Sivan, Sarit Sara; Hayes, Anthony J.; Wachtel, Ellen; Caterson, Bruce; Merkher, Yulia; Maroudas, Alice; Brown, Sharon; Roberts, Sally

Abstract

Background
The intervertebral disc (IVD) is a complex cartilaginous structure which functions to resist biomechanical loads during spinal movement. It consists of the highly viscous cartilaginous nucleus pulposus, which is surrounded laterally by a thick outer ring of fibrous cartilage—the annulus fibrosus—and sandwiched inferiorly and superiorly by the cartilage end-plates. The main extracellular matrix molecules of the disc are collagens, proteoglycans, glycoproteins and elastin. The disc also contains appreciable amounts of water, matrix-degrading protease enzymes and their inhibitors, soluble signalling molecules and various metabolic breakdown products.

Methods
This review provides a comprehensive description of the biochemical composition of the extracellular matrix of the IVD and, specifically, the proteases involved in its molecular turnover. Quantitation of the turnover rates using racemization of aspartic acid as a molecular clock is also discussed.

Conclusions
Molecular turnover rates of the major constituent matrix macromolecules of the IVD are found to be particularly slow, especially in the case of collagen. Over a normal human life span, this slow turnover may compromise the structural integrity of the IVD extracellular matrix essential for normal physiological functioning.

Citation

Sivan, S. S., Hayes, A. J., Wachtel, E., Caterson, B., Merkher, Y., Maroudas, A., …Roberts, S. (2014). Biochemical composition and turnover of the extracellular matrix of the normal and degenerate intervertebral disc. European Spine Journal, 23(S3), 344-353. https://doi.org/10.1007/s00586-013-2767-8

• Journal Article Type: Article
• Online Publication Date: Apr 17, 2013
• Publication Date: 2014-06
• Deposit Date: Jun 8, 2023
• Journal: European Spine Journal
• Print ISSN: 0940-6719
• Electronic ISSN: 1432-0932
• Publisher: Springer Verlag
• Peer Reviewed: Not Peer Reviewed
• Volume: 23
• Issue: S3
• Pages: 344-353
• DOI: https://doi.org/10.1007/s00586-013-2767-8
• Keywords: Orthopedics and Sports Medicine; Surgery