Proteoglycan degradation mimics static compression by altering the natural gradients in fibrillar organisation in cartilage

DOI: 10.1016/j.actbio.2019.07.055

Authors: Sheetal R. Inamdar (Queen Mary University of London) , Ettore Barbieri (Yokohama Institute for Earth Sciences (YES)) , Nicholas J. Terrill (Diamond Light Source) , Martin M. Knight (Queen Mary University of London) , Himadri S. Gupta (Queen Mary University of London)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Acta Biomaterialia

State: Published (Approved)
Published: July 2019
Diamond Proposal Number(s): 10311

Abstract: Structural and associated biomechanical gradients within biological tissues are important for tissue functionality and preventing damaging interfacial stress concentrations. Articular cartilage possesses an inhomogeneous structure throughout its thickness, driving the associated variation in the biomechanical strain profile within the tissue under physiological compressive loading. However, little is known experimentally about the nanostructural mechanical role of the collagen fibrils and how this varies with depth. Utilising a high-brilliance synchrotron X-ray source, we have measured the depth-wise nanostructural parameters of the collagen network in terms of the periodic fibrillar banding (D-period) and associated parameters. We show that there is a depth dependent variation in D-period reflecting the pre-strain and concurrent with changes in the level of intrafibrillar order. Further, prolonged static compression leads to fibrillar changes mirroring those caused by removal of extrafibrillar proteoglycans (as may occur in aging or disease). We suggest that fibrillar D-period is a sensitive indicator of localised changes to the mechanical environment at the nanoscale in soft connective tissues.

Journal Keywords: Cartilage; Biomechanics; Nanostructure; Collagen mechanics; Structural gradients

Subject Areas: Biology and Bio-materials


Instruments: I18-Microfocus Spectroscopy , I22-Small angle scattering & Diffraction

Added On: 06/08/2019 11:32

Documents:
hhfh444.pdf

Discipline Tags:

Soft condensed matter physics Nanoscience/Nanotechnology Life Sciences & Biotech

Technical Tags:

Scattering Small Angle X-ray Scattering (SAXS)