Microstructural differences in the osteochondral unit of terrestrial and aquatic mammals
- Utrecht University, Netherlands
- University Medical Center Utrecht, Netherlands
- Eindhoven University of Technology, Netherlands
- University of Adelaide, Netherlands
Abstract
During evolution, animals have returned from land to water, adapting with morphological modifications to life in an aquatic environment. We compared the osteochondral units of the humeral head of marine and terrestrial mammals across species spanning a wide range of body weights, focusing on microstructural organization and biomechanical performance. Aquatic mammals feature cartilage with essentially random collagen fiber configuration, lacking the depth-dependent, arcade-like organization characteristic of terrestrial mammalian species. They have a less stiff articular cartilage at equilibrium with a significantly lower peak modulus, and at the osteochondral interface do not have a calcified cartilage layer, displaying only a thin, highly porous subchondral bone plate. This totally different constitution of the osteochondral unit in aquatic mammals reflects that accommodation of loading is the primordial function of the osteochondral unit. Recognizing the crucial importance of the microarchitecture-function relationship is pivotal for understanding articular biology and, hence, for the development of durable functional regenerative approaches for treatment of joint damage, which are thus far lacking.
Data availability
Data generated or analysed during this study are included in the manuscript and supporting file; Source Data files have been provided for Figure 1.
Article and author information
Author details
Lonneke L IJsseldijk
Funding
European Commission (3099622 (FP7))
- Irina AD Mancini
- René van Weeren
- Jos Malda
Dutch Arthritis Society (LLP12 and LLP22)
- Riccardo Levato
- Miguel Dias Castilho
- René van Weeren
- Jos Malda
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Di Chen, Chinese Academy of Sciences, China
Version history
- Preprint posted: June 10, 2022 (view preprint)
- Received: June 10, 2022
- Accepted: November 24, 2023
- Accepted Manuscript published: November 27, 2023 (version 1)
- Version of Record published: January 10, 2024 (version 2)
Copyright
© 2023, Mancini et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Microstructural differences in the osteochondral unit of terrestrial and aquatic mammals
eLife 12:e80936.
https://doi.org/10.7554/eLife.80936
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