Previous studies have shown that static equilibrium compression of cartilage tissue in vivo and in vitro decreases chondrocyte synthesis of aggrecan molecules. In order to identify mechanisms of cellular response to loading, we have investigated alterations in cell and nucleus structure and the accompanying changes in the synthesis of aggrecan in statically compressed cartilage explants. Using glutaraldehyde fixation and quantitative autoradiography of compressed and radiolabeled cartilage disks we spatially localized newly synthesized aggrecan. Using stereological tools to analyze these same specimens we estimated the cell and nucleus volume, surface area and directional radii. We found that aggrecan synthesis was reduced overall in compressed tissue disks. However, the compression induced a spatial (radial) inhomogeneity in aggrecan synthesis which was not present in uncompressed disks. This spatial inhomogeneity appeared to be directly related to mechanical boundary conditions and the manner in which the load was applied and, therefore, may represent a spatially specific functional adaptation to mechanical loading. Coincident with reduced aggrecan synthesis, we observed reductions in cell and nucleus volume and radii in the direction of compression which were in approximate proportion to the reduction in tissue thickness. Cell and nucleus dimensions perpendicular to the direction of compression did not change significantly. Therefore the observed deformation of the cell and nucleus in statically compressed cartilage approximately followed the dimensional changes imposed on external specimen surfaces. The strong correlation observed between local changes in aggrecan synthesis and alterations in cell and nucleus structure also lend support to certain hypotheses regarding the intracellular signal transduction pathways that may be important in the biosynthetic response of chondrocytes to mechanical loading.
Altered aggrecan synthesis correlates with cell and nucleus structure in statically compressed cartilage
M.D. Buschmann, E.B. Hunziker, Y.J. Kim, A.J. Grodzinsky; Altered aggrecan synthesis correlates with cell and nucleus structure in statically compressed cartilage. J Cell Sci 1 February 1996; 109 (2): 499–508. doi: https://doi.org/10.1242/jcs.109.2.499
Download citation file:
Advertisement
Cited by
2021 JCS Prize winner announced
-JCSPrize.png?versionId=3749)
We are pleased to announce that the winner of the 2021 JCS Prize is Lee Dolat for his paper entitled ‘An endometrial organoid model of interactions between Chlamydia and epithelial and immune cells’.
Propose a new Workshop
-GSWorkshop.png?versionId=3749)
Our Workshops bring together leading experts and early-career researchers from a range of scientific backgrounds. Applications are now open to propose Workshops for 2024, one of which will be held in a Global South country.
Cell scientist to watch: Christian Münch
-CSTW.png?versionId=3749)
Journal of Cell Science interviewed Christian Münch, who established his independent research group in 2016 at Goethe University Frankfurt. His lab studies cellular stress responses to mitochondrial protein misfolding, infection and disease, as well as developing proteomics methods.
Essay series: Equity, diversity and inclusion in cell biology
-EssaySeries.png?versionId=3749)
The JCS Essay Series is an initiative to help showcase and provide a platform for voices in the field of cell biology. The first topic we covered was 'Equity, diversity and inclusion in cell biology', and the winning and runner up essays are now available to read.
FocalPlane Network launched
-FocalPlaneNetworkLaunch.png?versionId=3749)
We are excited to announce the launch of the FocalPlane Network, an international directory of microscopists. The idea behind the FocalPlane Network is to facilitate promotion and networking as well as assist those seeking conference speakers, committee members, reviewers or collaborators. We hope that it will help promote diversity in the community. Find out more and join the Network here.