Investigating the Role of Proteoglycans in Fibril Sliding

Recent studies have demonstrated that modification to the extracellular matrix has altered the micromechanical behaviour of collagen fibrils in tendon. However, the effects of matrix modification on the micromechanical properties in the annulus fibrosus are undefined. The present study aimed to assess the impact of glycosaminoglycan loss from the inner annulus on the micromechanical behaviour of collagen fibrils.

Glycosaminoglycan loss was quantified from explants and intact disc specimens either chondroitinase ABC-treated, sham-treated or untreated using the DMMB Assay. Fresh discs were loaded in flexion after treatment, with concurrent confocal imaging to assess changes in the extracellular matrix.

Confocal images revealed no gross morphological differences between the three groups. Analysis of local deflections revealed no significant differences in the micromechanical behaviour of the collagen fibrils.

The present study indicates that the micromechanical behaviour of collagen fibrils in the annulus fibrosus is not overtly influenced by removal of the associated glycosaminoglycans.

Year	Entry
2002	Hulme PA. Methods to Determine the Microscopic and Macroscopic Swelling Behaviour of the Annulus Fibrosus [Master's thesis]. Calgary, AB: University of Calgary; June 2002.
1988	Urban JPG, McMullin JF. Swelling pressure of the lumbar intervertebral discs influence of age, spinal level, composition, and degeneration. Spine. February 1988;13(2):179-187.
2003	Silver FH, Freeman JW, Seehra GP. Collagen self-assembly and the development of tendon mechanical properties. J Biomech. October 2003;36(10):1529-1553.
2001	Knudson CB, Knudson W. Cartilage proteoglycans. Semin Cell Dev Biol. April 2001;12(2):69-78.
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Year

Entry

2002

Hulme PA. Methods to Determine the Microscopic and Macroscopic Swelling Behaviour of the Annulus Fibrosus [Master's thesis]. Calgary, AB: University of Calgary; June 2002.

1988

Urban JPG, McMullin JF. Swelling pressure of the lumbar intervertebral discs influence of age, spinal level, composition, and degeneration. Spine. February 1988;13(2):179-187.

2003

Silver FH, Freeman JW, Seehra GP. Collagen self-assembly and the development of tendon mechanical properties. J Biomech. October 2003;36(10):1529-1553.

2001

Knudson CB, Knudson W. Cartilage proteoglycans. Semin Cell Dev Biol. April 2001;12(2):69-78.

1981

Urban JPG, Maroudas A. Swelling of the intervertebral disc in vitro. Connect Tissue Res. 1981;9(1):1-10.