Affordable Access

Publisher Website

Osteoarthritic changes in the biphasic mechanical properties of the chondrocyte pericellular matrix in articular cartilage

Authors
Journal
Journal of Biomechanics
0021-9290
Publisher
Elsevier
Publication Date
Volume
38
Issue
3
Identifiers
DOI: 10.1016/j.jbiomech.2004.04.012
Keywords
  • Chondron
  • Cell Mechanics
  • Micropipette
  • Pericellular Matrix
  • Osteoarthritis
  • Articular Cartilage
  • Modulus
  • Permeability
  • Biphasic
  • Finite Element Model
Disciplines
  • Chemistry
  • Physics

Abstract

Abstract The pericellular matrix (PCM) is a narrow region of cartilaginous tissue that surrounds chondrocytes in articular cartilage. Previous modeling studies indicate that the mechanical properties of the PCM relative to those of the extracellular matrix (ECM) can significantly affect the stress–strain, fluid flow, and physicochemical environments of the chondrocyte, suggesting that the PCM plays a biomechanical role in articular cartilage. The goals of this study were to measure the mechanical properties of the PCM using micropipette aspiration coupled with a linear biphasic finite element model, and to determine the alterations in the mechanical properties of the PCM with osteoarthritis (OA). Using a recently developed isolation technique, chondrons (the chondrocyte and its PCM) were mechanically extracted from non-degenerate and osteoarthritic human cartilage. The transient mechanical behavior of the PCM was well-described by a biphasic model, suggesting that the viscoelastic response of the PCM is attributable to flow-dependent effects, similar to that of the ECM. With OA, the mean Young's modulus of the PCM was significantly decreased (38.7±16.2 kPa vs. 23.5±12.9 kPa, p<0.001), and the permeability was significantly elevated (4.19±3.78×10 −17 m 4/N s vs. 10.2±9.38×10 −17 m 4/N s, p<0.001). The Poisson's ratio was similar for both non-degenerate and OA PCM (0.044±0.063 vs. 0.030±0.068, p>0.6). These findings suggest that the PCM may undergo degenerative processes with OA, similar to those occurring in the ECM. In combination with previous theoretical models of cell–matrix interactions in cartilage, our findings suggest that changes in the properties of the PCM with OA may have an important influence on the biomechanical environment of the chondrocyte.

There are no comments yet on this publication. Be the first to share your thoughts.