1
|
Eisner LE, Rosario R, Andarawis-Puri N, Arruda EM. The Role of the Non-Collagenous Extracellular Matrix in Tendon and Ligament Mechanical Behavior: A Review. J Biomech Eng 2022; 144:1128818. [PMID: 34802057 PMCID: PMC8719050 DOI: 10.1115/1.4053086] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Indexed: 12/26/2022]
Abstract
Tendon is a connective tissue that transmits loads from muscle to bone, while ligament is a similar tissue that stabilizes joint articulation by connecting bone to bone. The 70-90% of tendon and ligament's extracellular matrix (ECM) is composed of a hierarchical collagen structure that provides resistance to deformation primarily in the fiber direction, and the remaining fraction consists of a variety of non-collagenous proteins, proteoglycans, and glycosaminoglycans (GAGs) whose mechanical roles are not well characterized. ECM constituents such as elastin, the proteoglycans decorin, biglycan, lumican, fibromodulin, lubricin, and aggrecan and their associated GAGs, and cartilage oligomeric matrix protein (COMP) have been suggested to contribute to tendon and ligament's characteristic quasi-static and viscoelastic mechanical behavior in tension, shear, and compression. The purpose of this review is to summarize existing literature regarding the contribution of the non-collagenous ECM to tendon and ligament mechanics, and to highlight key gaps in knowledge that future studies may address. Using insights from theoretical mechanics and biology, we discuss the role of the non-collagenous ECM in quasi-static and viscoelastic tensile, compressive, and shear behavior in the fiber direction and orthogonal to the fiber direction. We also address the efficacy of tools that are commonly used to assess these relationships, including enzymatic degradation, mouse knockout models, and computational models. Further work in this field will foster a better understanding of tendon and ligament damage and healing as well as inform strategies for tissue repair and regeneration.
Collapse
Affiliation(s)
- Lainie E Eisner
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109; Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853
| | - Ryan Rosario
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Nelly Andarawis-Puri
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853
| | - Ellen M Arruda
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109; Professor Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109; Professor Program in Macromolecular Science and Engineering, University of Michigan, Ann Arbor, MI 48109
| |
Collapse
|
2
|
Goh KL, Holmes DF. Collagenous Extracellular Matrix Biomaterials for Tissue Engineering: Lessons from the Common Sea Urchin Tissue. Int J Mol Sci 2017; 18:ijms18050901. [PMID: 28441344 PMCID: PMC5454814 DOI: 10.3390/ijms18050901] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 04/05/2017] [Accepted: 04/11/2017] [Indexed: 12/21/2022] Open
Abstract
Scaffolds for tissue engineering application may be made from a collagenous extracellular matrix (ECM) of connective tissues because the ECM can mimic the functions of the target tissue. The primary sources of collagenous ECM material are calf skin and bone. However, these sources are associated with the risk of having bovine spongiform encephalopathy or transmissible spongiform encephalopathy. Alternative sources for collagenous ECM materials may be derived from livestock, e.g., pigs, and from marine animals, e.g., sea urchins. Collagenous ECM of the sea urchin possesses structural features and mechanical properties that are similar to those of mammalian ones. However, even more intriguing is that some tissues such as the ligamentous catch apparatus can exhibit mutability, namely rapid reversible changes in the tissue mechanical properties. These tissues are known as mutable collagenous tissues (MCTs). The mutability of these tissues has been the subject of on-going investigations, covering the biochemistry, structural biology and mechanical properties of the collagenous components. Recent studies point to a nerve-control system for regulating the ECM macromolecules that are involved in the sliding action of collagen fibrils in the MCT. This review discusses the key attributes of the structure and function of the ECM of the sea urchin ligaments that are related to the fibril-fibril sliding action-the focus is on the respective components within the hierarchical architecture of the tissue. In this context, structure refers to size, shape and separation distance of the ECM components while function is associated with mechanical properties e.g., strength and stiffness. For simplicity, the components that address the different length scale from the largest to the smallest are as follows: collagen fibres, collagen fibrils, interfibrillar matrix and collagen molecules. Application of recent theories of stress transfer and fracture mechanisms in fibre reinforced composites to a wide variety of collagen reinforcing (non-mutable) connective tissue, has allowed us to draw general conclusions concerning the mechanical response of the MCT at specific mechanical states, namely the stiff and complaint states. The intent of this review is to provide the latest insights, as well as identify technical challenges and opportunities, that may be useful for developing methods for effective mechanical support when adapting decellularised connective tissues from the sea urchin for tissue engineering or for the design of a synthetic analogue.
Collapse
Affiliation(s)
- Kheng Lim Goh
- Newcastle University Singapore, SIT Building at Nanyang Polytechnic, 172A Ang Mo Kio Avenue 8 #05-01, Singapore 567739, Singapore.
- Newcastle University, School of Mechanical & Systems Engineering, Stephenson Building, Claremont Road, Newcastle upon Tyne NE1 7RU, UK.
| | - David F Holmes
- Manchester University, Wellcome Trust Centre for Cell Matrix Research, B.3016 Michael Smith Building, Faculty of Life Sciences, Oxford Road, Manchester M13 9PT, UK.
| |
Collapse
|
3
|
Changes in collagenous tissue microstructures and distributions of cathepsin L in body wall of autolytic sea cucumber (Stichopus japonicus). Food Chem 2016; 212:341-8. [DOI: 10.1016/j.foodchem.2016.05.173] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Revised: 05/16/2016] [Accepted: 05/27/2016] [Indexed: 11/15/2022]
|
4
|
Watanabe T, Kametani K, Koyama YI, Suzuki D, Imamura Y, Takehana K, Hiramatsu K. Ring-Mesh Model of Proteoglycan Glycosaminoglycan Chains in Tendon based on Three-dimensional Reconstruction by Focused Ion Beam Scanning Electron Microscopy. J Biol Chem 2016; 291:23704-23708. [PMID: 27624935 DOI: 10.1074/jbc.m116.733857] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Indexed: 11/06/2022] Open
Abstract
Tendons are composed of collagen fibrils and proteoglycan predominantly consisting of decorin. Decorin is located on the d-band of collagen fibrils, and its glycosaminoglycan (GAG) chains have been observed between collagen fibrils with transmission electron microscopy. GAG chains have been proposed to interact with each other or with collagen fibrils, but its three-dimensional organization remains unclear. In this report, we used focused ion beam scanning electron microscopy to examine the three-dimensional organization of the GAG chain in the Achilles tendon of mature rats embedded in epoxy resin after staining with Cupromeronic blue, which specifically stains GAG chains. We used 250 serial back-scattered electron images of longitudinal sections with a 10-nm interval for reconstruction. Three-dimensional images revealed that GAG chains form a ring mesh-like structure with each ring surrounding a collagen fibril at the d-band and fusing with adjacent rings to form the planar network. This ring mesh model of GAG chains suggests that more than two GAG chains may interact with each other around collagen fibrils, which could provide new insights into the roles of GAG chains.
Collapse
Affiliation(s)
- Takafumi Watanabe
- From the Faculty of Agriculture, Shinshu University, Minami-minowa, Kami-ina, Nagano 399-4598, Japan,
| | - Kiyokazu Kametani
- Department of Instrumental Analysis, Research Center for Human and Environmental Science, Shinshu University, Asahi, Matsumoto, Nagano 390-8621, Japan
| | - Yoh-Ichi Koyama
- Research Institute of Biomatrix, Nippi Inc., Kuwabara, Toride, Ibaraki 302-0017, Japan
| | - Daisuke Suzuki
- Department of Musculoskeletal Biomechanics and Surgical Development, School of Medicine, Sapporo Medical University, Sapporo, Hokkaido 060-8556, Japan
| | - Yasutada Imamura
- Department of Chemistry and Life Science, School of Advanced Engineering, Kogakuin University, Hachioji, Tokyo 192-0015, Japan, and
| | - Kazushige Takehana
- School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan
| | - Kohzy Hiramatsu
- From the Faculty of Agriculture, Shinshu University, Minami-minowa, Kami-ina, Nagano 399-4598, Japan
| |
Collapse
|
5
|
Wong WLE, Joyce TJ, Goh KL. Resolving the viscoelasticity and anisotropy dependence of the mechanical properties of skin from a porcine model. Biomech Model Mechanobiol 2015; 15:433-46. [PMID: 26156308 DOI: 10.1007/s10237-015-0700-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 06/29/2015] [Indexed: 11/29/2022]
Abstract
The mechanical response of skin to external loads is influenced by anisotropy and viscoelasticity of the tissue, but the underlying mechanisms remain unclear. Here, we report a study of the main effects of tissue orientation (TO, which is linked to anisotropy) and strain rate (SR, a measure of viscoelasticity), as well as the interaction effects between the two factors, on the tensile properties of skin from a porcine model. Tensile testing to rupture of porcine skin tissue was conducted to evaluate the sensitivity of the tissue modulus of elasticity (E) and fracture-related properties, namely maximum stress (σU) and strain (εU) at σU, to varying SR and TO. Specimens were excised from the abdominal skin in two orientations, namely parallel (P) and right angle (R) to the torso midline. Each TO was investigated at three SR levels, namely 0.007-0.015 s(-1) (low), 0.040 s(-1) (mid) and 0.065 s(-1) (high). Two-factor analysis of variance revealed that the respective parameters responded differently to varying SR and TO. Significant changes in the σU were observed with different TOs but not with SR. The εU decreased significantly with increasing SR, but no significant variation was observed for different TOs. Significant changes in E were observed with different TOs; E increased significantly with increasing SR. More importantly, the respective mechanical parameters were not significantly influenced by interactions between SR and TO. These findings suggest that the trends associated with the changes in the skin mechanical properties may be attributed partly to differences in the anisotropy and viscoelasticity but not through any interaction between viscoelasticity and anisotropy.
Collapse
Affiliation(s)
- W L E Wong
- NUInternational Singapore Pte Ltd, Singapore, 569830, Singapore.,School of Mechanical and Systems Engineering, Newcastle University, Newcastle Upon Tyne, NE1 7RU, England, UK
| | - T J Joyce
- School of Mechanical and Systems Engineering, Newcastle University, Newcastle Upon Tyne, NE1 7RU, England, UK
| | - K L Goh
- NUInternational Singapore Pte Ltd, Singapore, 569830, Singapore. .,School of Mechanical and Systems Engineering, Newcastle University, Newcastle Upon Tyne, NE1 7RU, England, UK.
| |
Collapse
|
6
|
Szczesny SE, Elliott DM. Incorporating plasticity of the interfibrillar matrix in shear lag models is necessary to replicate the multiscale mechanics of tendon fascicles. J Mech Behav Biomed Mater 2014; 40:325-338. [PMID: 25262202 DOI: 10.1016/j.jmbbm.2014.09.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 08/26/2014] [Accepted: 09/02/2014] [Indexed: 11/18/2022]
Abstract
Despite current knowledge of tendon structure, the fundamental deformation mechanisms underlying tendon mechanics and failure are unknown. We recently showed that a shear lag model, which explicitly assumed plastic interfibrillar load transfer between discontinuous fibrils, could explain the multiscale fascicle mechanics, suggesting that fascicle yielding is due to plastic deformation of the interfibrillar matrix. However, it is unclear whether alternative physical mechanisms, such as elastic interfibrillar deformation or fibril yielding, also contribute to fascicle mechanical behavior. The objective of the current work was to determine if plasticity of the interfibrillar matrix is uniquely capable of explaining the multiscale mechanics of tendon fascicles including the tissue post-yield behavior. This was examined by comparing the predictions of a continuous fibril model and three separate shear lag models incorporating an elastic, plastic, or elastoplastic interfibrillar matrix with multiscale experimental data. The predicted effects of fibril yielding on each of these models were also considered. The results demonstrated that neither the continuous fibril model nor the elastic shear lag model can successfully predict the experimental data, even if fibril yielding is included. Only the plastic or elastoplastic shear lag models were capable of reproducing the multiscale tendon fascicle mechanics. Differences between these two models were small, although the elastoplastic model did improve the fit of the experimental data at low applied tissue strains. These findings suggest that while interfibrillar elasticity contributes to the initial stress response, plastic deformation of the interfibrillar matrix is responsible for tendon fascicle post-yield behavior. This information sheds light on the physical processes underlying tendon failure, which is essential to improve our understanding of tissue pathology and guide the development of successful repair.
Collapse
Affiliation(s)
- Spencer E Szczesny
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33rd St, Philadelphia, PA 19104, United States.
| | - Dawn M Elliott
- Department of Biomedical Engineering, University of Delaware, 125 East Delaware Avenue, Newark, DE 19716, United States.
| |
Collapse
|
7
|
Szczesny SE, Elliott DM. Interfibrillar shear stress is the loading mechanism of collagen fibrils in tendon. Acta Biomater 2014; 10:2582-90. [PMID: 24530560 DOI: 10.1016/j.actbio.2014.01.032] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 12/04/2013] [Accepted: 01/30/2014] [Indexed: 12/15/2022]
Abstract
Despite the critical role tendons play in transmitting loads throughout the musculoskeletal system, little is known about the microstructural mechanisms underlying their mechanical function. Of particular interest is whether collagen fibrils in tendon fascicles bear load independently or if load is transferred between fibrils through interfibrillar shear forces. We conducted multiscale experimental testing and developed a microstructural shear lag model to explicitly test whether interfibrillar shear load transfer is indeed the fibrillar loading mechanism in tendon. Experimental correlations between fascicle macroscale mechanics and microscale interfibrillar sliding suggest that fibrils are discontinuous and share load. Moreover, for the first time, we demonstrate that a shear lag model can replicate the fascicle macroscale mechanics as well as predict the microscale fibrillar deformations. Since interfibrillar shear stress is the fundamental loading mechanism assumed in the model, this result provides strong evidence that load is transferred between fibrils in tendon and possibly other aligned collagenous tissues. Conclusively establishing this fibrillar loading mechanism and identifying the involved structural components should help develop repair strategies for tissue degeneration and guide the design of tissue engineered replacements.
Collapse
Affiliation(s)
- Spencer E Szczesny
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33rd St, Philadelphia, PA 19104, USA
| | - Dawn M Elliott
- Department of Biomedical Engineering, University of Delaware, 125 East Delaware Avenue, Newark, DE 19716, USA.
| |
Collapse
|
8
|
Bigg PW, Baldo G, Sleeper MM, O'Donnell PA, Bai H, Rokkam VR, Liu Y, Wu S, Giugliani R, Casal ML, Haskins ME, Ponder KP. Pathogenesis of mitral valve disease in mucopolysaccharidosis VII dogs. Mol Genet Metab 2013; 110:319-28. [PMID: 23856419 PMCID: PMC3800211 DOI: 10.1016/j.ymgme.2013.06.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 06/18/2013] [Indexed: 01/02/2023]
Abstract
Mucopolysaccharidosis VII (MPS VII) is due to the deficient activity of β-glucuronidase (GUSB) and results in the accumulation of glycosaminoglycans (GAGs) in lysosomes and multisystemic disease with cardiovascular manifestations. The goal here was to determine the pathogenesis of mitral valve (MV) disease in MPS VII dogs. Untreated MPS VII dogs had a marked reduction in the histochemical signal for structurally-intact collagen in the MV at 6 months of age, when mitral regurgitation had developed. Electron microscopy demonstrated that collagen fibrils were of normal diameter, but failed to align into large parallel arrays. mRNA analysis demonstrated a modest reduction in the expression of genes that encode collagen or collagen-associated proteins such as the proteoglycan decorin which helps collagen fibrils assemble, and a marked increase for genes that encode proteases such as cathepsins. Indeed, enzyme activity for cathepsin B (CtsB) was 19-fold normal. MPS VII dogs that received neonatal intravenous injection of a gamma retroviral vector had an improved signal for structurally-intact collagen, and reduced CtsB activity relative to that seen in untreated MPS VII dogs. We conclude that MR in untreated MPS VII dogs was likely due to abnormalities in MV collagen structure. This could be due to upregulation of enzymes that degrade collagen or collagen-associated proteins, to the accumulation of GAGs that compete with proteoglycans such as decorin for binding to collagen, or to other causes. Further delineation of the etiology of abnormal collagen structure may lead to treatments that improve biomechanical properties of the MV and other tissues.
Collapse
Affiliation(s)
- Paul W. Bigg
- Department of Internal Medicine, Washington University School of Medicine, St. Louis MO
| | - Guilherme Baldo
- Programa de Pos-Graduacao em Genetica e Biologia Molecular, Universidade Federal do Rio Grande do Sul, RS, Brazil
| | - Meg M. Sleeper
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Patricia A. O'Donnell
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Hanqing Bai
- Department of Internal Medicine, Washington University School of Medicine, St. Louis MO
| | - Venkata R.P. Rokkam
- Department of Internal Medicine, Washington University School of Medicine, St. Louis MO
| | - Yuli Liu
- Department of Internal Medicine, Washington University School of Medicine, St. Louis MO
| | - Susan Wu
- Department of Internal Medicine, Washington University School of Medicine, St. Louis MO
| | - Roberto Giugliani
- Programa de Pos-Graduacao em Genetica e Biologia Molecular, Universidade Federal do Rio Grande do Sul, RS, Brazil
| | - Margret L. Casal
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Mark E. Haskins
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Katherine P. Ponder
- Department of Internal Medicine, Washington University School of Medicine, St. Louis MO
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis MO
| |
Collapse
|
9
|
Bennett CB, Kruczek J, Rabson DA, Matthews WG, Pandit SA. The effect of cross-link distributions in axially-ordered, cross-linked networks. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:285101. [PMID: 23751928 PMCID: PMC3783025 DOI: 10.1088/0953-8984/25/28/285101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Cross-linking between the constituent chains of biopolymers has a marked effect on their materials' properties. In certain of these materials, such as fibrillar collagen, increases in cross-linking lead to an increase in the melting temperature. Fibrillar collagen is an axially-ordered network of cross-linked polymer chains exhibiting a broadened denaturation transition, which has been explained in terms of the successive denaturation with temperature of multiple species. We model axially-ordered, cross-linked materials as stiff chains with distinct arrangements of cross-link-forming sites. Simulations suggest that systems composed of chains with identical arrangements of cross-link-forming sites exhibit critical behavior. In contrast, systems composed of non-identical chains undergo a crossover. This model suggests that the arrangement of cross-link-forming sites may contribute to the broadening of the denaturation transition in fibrillar collagen.
Collapse
Affiliation(s)
- C Brad Bennett
- Department of Physics, University of South Florida, Tampa, FL 33620, USA
| | | | | | | | | |
Collapse
|
10
|
Panwar P, Du X, Sharma V, Lamour G, Castro M, Li H, Brömme D. Effects of cysteine proteases on the structural and mechanical properties of collagen fibers. J Biol Chem 2013; 288:5940-50. [PMID: 23297404 DOI: 10.1074/jbc.m112.419689] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Excessive cathepsin K (catK)-mediated turnover of fibrillar type I and II collagens in bone and cartilage leads to osteoporosis and osteoarthritis. However, little is known about how catK degrades compact collagen macromolecules. The present study is aimed to explore the structural and mechanical consequences of collagen fiber degradation by catK. Mouse tail type I collagen fibers were incubated with either catK or non-collagenase cathepsins. Methods used include scanning electron microscopy, protein electrophoresis, atomic force microscopy, and tensile strength testing. Our study revealed evidence of proteoglycan network degradation, followed by the progressive disassembly of macroscopic collagen fibers into primary structural elements by catK. Proteolytically released GAGs are involved in the generation of collagenolytically active catK-GAG complexes as shown by AFM. In addition to their structural disintegration, a decrease in the tensile properties of fibers was observed due to the action of catK. The Young's moduli of untreated collagen fibers versus catK-treated fibers in dehydrated conditions were 3.2 ± 0.68 GPa and 1.9 ± 0.65 GPa, respectively. In contrast, cathepsin L, V, B, and S revealed no collagenase activity, except the disruption of proteoglycan-GAG interfibrillar bridges, which slightly decreased the tensile strength of fibers.
Collapse
Affiliation(s)
- Preety Panwar
- Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, Vancouver, British Columbia V6T1Z3, Canada
| | | | | | | | | | | | | |
Collapse
|
11
|
Goh KL, Holmes DF, Lu Y, Purslow PP, Kadler KE, Bechet D, Wess TJ. Bimodal collagen fibril diameter distributions direct age-related variations in tendon resilience and resistance to rupture. J Appl Physiol (1985) 2012; 113:878-88. [PMID: 22837169 DOI: 10.1152/japplphysiol.00258.2012] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Scaling relationships have been formulated to investigate the influence of collagen fibril diameter (D) on age-related variations in the strain energy density of tendon. Transmission electron microscopy was used to quantify D in tail tendon from 1.7- to 35.3-mo-old (C57BL/6) male mice. Frequency histograms of D for all age groups were modeled as two normally distributed subpopulations with smaller (D(D1)) and larger (D(D2)) mean Ds, respectively. Both D(D1) and D(D2) increase from 1.6 to 4.0 mo but decrease thereafter. From tensile tests to rupture, two strain energy densities were calculated: 1) u(E) [from initial loading until the yield stress (σ(Y))], which contributes primarily to tendon resilience, and 2) u(F) [from σ(Y) through the maximum stress (σ(U)) until rupture], which relates primarily to resistance of the tendons to rupture. As measured by the normalized strain energy densities u(E)/σ(Y) and u(F)/σ(U), both the resilience and resistance to rupture increase with increasing age and peak at 23.0 and 4.0 mo, respectively, before decreasing thereafter. Multiple regression analysis reveals that increases in u(E)/σ(Y) (resilience energy) are associated with decreases in D(D1) and increases in D(D2), whereas u(F)/σ(U) (rupture energy) is associated with increases in D(D1) alone. These findings support a model where age-related variations in tendon resilience and resistance to rupture can be directed by subtle changes in the bimodal distribution of Ds.
Collapse
Affiliation(s)
- K L Goh
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore.
| | | | | | | | | | | | | |
Collapse
|
12
|
Watanabe T, Imamura Y, Suzuki D, Hosaka Y, Ueda H, Hiramatsu K, Takehana K. Concerted and adaptive alignment of decorin dermatan sulfate filaments in the graded organization of collagen fibrils in the equine superficial digital flexor tendon. J Anat 2011; 220:156-63. [PMID: 22122012 DOI: 10.1111/j.1469-7580.2011.01456.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The equine superficial digital flexor tendon (SDFT) has a graded distribution of collagen fibril diameters, with predominantly small-diameter fibrils in the region of the myotendinous junction (MTJ), a gradual increase in large-diameter fibrils toward the osteotendinous junction (OTJ), and a mixture of small- and large-diameter fibrils in the middle metacarpal (MM) region. In this study, we investigated the ultrastructure of the SDFT, to correlate the spatial relationship of the collagen fibrils with the graded distribution. The surface-to-surface distances of pairs of fibrils were found to be almost constant over the entire tendon. However, the center-to-center distances varied according to fibril diameter. Decorin is the predominant proteoglycan in normal mature tendons, and has one dermatan sulfate (DS) or chondroitin sulfate (CS) filament as a side chain which is associated with the surfaces of the collagen fibrils via its core protein. We identified a coordinated arrangement of decorin DS filaments in the equine SDFT. The sizes of the decorin DS filaments detected by Cupromeronic blue staining showed a unique regional variation; they were shortest in the MM region and longer in the MTJ and OTJ regions, and a considerable number of filaments were arranged obliquely to adjacent collagen fibrils in the MTJ region. This regional variation of the filaments may be an adaptation to lubricate the interfibrillar space in response to local mechanical requirements. The results of this study suggest that the MTJ region, which receives the muscular contractile force first, acts as a buffer for mechanical forces in the equine SDFT.
Collapse
Affiliation(s)
- Takafumi Watanabe
- Laboratory of Animal Functional Anatomy, Department of Food Production Science, Faculty of Agriculture, Shinshu University, Nagano, Japan
| | | | | | | | | | | | | |
Collapse
|
13
|
Lewis JL, Krawczak DA, Oegema TR, Westendorf JJ. Effect of decorin and dermatan sulfate on the mechanical properties of a neocartilage. Connect Tissue Res 2010; 51:159-70. [PMID: 20001848 DOI: 10.3109/03008200903174342] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Decorin is known to influence the size of collagen fibrils in ligaments and tendons and it has been hypothesized to provide a structural link between collagen fibrils in connective tissues, including cartilage. Coincidently, mechanical properties of skin, ligament, and tendons are altered in decorin knockout mice, suggesting it may influence the structural properties of tissue or tissue matrix organization. To further examine the role of decorin in the extracellular matrix development and subsequent material properties of cartilage, tissue (neocartilage) was grown in a 3D culture model using a pure population of genetically modified chondrocytes stably overexpressing decorin (DCN) or decorin lacking dermatan sulfate (MDCN). An empty vector (CON) served as a virus control. Following generation of the cartilage-like tissues, mechanical properties in tension and compression, collagen fibril diameter, matrix organization, and biochemistry of the tissue were determined. There were no differences between CON and DCN tissues in any parameter measured. In contrast, tissue generated in MDCN cultures was thinner, had higher collagen density, and higher elastic moduli as compared to both CON and DCN tissues. Considering there was no difference in stiffness between CON and DCN tissues, the notion that decorin contributes to the mechanical properties via load transfer was refuted in this model. However, contrasts in the mechanical properties of the MDCN tissue suggest that the dermatan sulfate chains on decorin influences the organization/maturation and resultant mechanical properties of the matrix by as an yet-unidentified regulatory mechanism.
Collapse
Affiliation(s)
- Jack L Lewis
- Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, Minnesota 55455, USA.
| | | | | | | |
Collapse
|
14
|
Dermatan sulfate epimerase 1-deficient mice have reduced content and changed distribution of iduronic acids in dermatan sulfate and an altered collagen structure in skin. Mol Cell Biol 2009; 29:5517-28. [PMID: 19687302 DOI: 10.1128/mcb.00430-09] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Dermatan sulfate epimerase 1 (DS-epi1) and DS-epi2 convert glucuronic acid to iduronic acid in chondroitin/dermatan sulfate biosynthesis. Here we report on the generation of DS-epi1-null mice and the resulting alterations in the chondroitin/dermatan polysaccharide chains. The numbers of long blocks of adjacent iduronic acids are greatly decreased in skin decorin and biglycan chondroitin/dermatan sulfate, along with a parallel decrease in iduronic-2-O-sulfated-galactosamine-4-O-sulfated structures. Both iduronic acid blocks and iduronic acids surrounded by glucuronic acids are also decreased in versican-derived chains. DS-epi1-deficient mice are smaller than their wild-type littermates but otherwise have no gross macroscopic alterations. The lack of DS-epi1 affects the chondroitin/dermatan sulfate in many proteoglycans, and the consequences for skin collagen structure were initially analyzed. We found that the skin collagen architecture was altered, and electron microscopy showed that the DS-epi1-null fibrils have a larger diameter than the wild-type fibrils. The altered chondroitin/dermatan sulfate chains carried by decorin in skin are likely to affect collagen fibril formation and reduce the tensile strength of DS-epi1-null skin.
Collapse
|
15
|
Hall ML, Krawczak DA, Simha NK, Lewis JL. Effect of dermatan sulfate on the indentation and tensile properties of articular cartilage. Osteoarthritis Cartilage 2009; 17:655-61. [PMID: 19036614 PMCID: PMC2717628 DOI: 10.1016/j.joca.2008.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Accepted: 10/22/2008] [Indexed: 02/02/2023]
Abstract
OBJECTIVE This paper examines the hypothesis that the dermatan sulfate (DS) chain on decorin is a load carrying element in cartilage and that its damage or removal will alter the material properties. METHODS To test this hypothesis, indentation and tensile testing of cartilage from bovine patella were performed before and after digestion with chondroitinase B (cB). Removal of significant amounts of DS by cB digestion was verified by Western blot analysis of proteoglycans extracted from whole and sectioned specimens. Specimens (control and treated) were subjected to a series of step-hold displacements. Elastic modulus during the step rise (rapid modulus) and at equilibrium (equilibrium modulus), and the relaxation function during each step was measured for test (cB and buffer) and control (buffer alone) conditions. RESULTS cB had no effect on any of the viscoelastic mechanical properties measured, either in indentation or tension. CONCLUSION Removing or damaging approximately 50% of the DS had no effect on the mechanical properties, strongly suggesting that DS either carries very low load or no load.
Collapse
Affiliation(s)
- M L Hall
- Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, MN 55455, USA
| | | | | | | |
Collapse
|
16
|
Henninger HB, Maas SA, Shepherd JH, Joshi S, Weiss JA. Transversely isotropic distribution of sulfated glycosaminoglycans in human medial collateral ligament: a quantitative analysis. J Struct Biol 2008; 165:176-83. [PMID: 19126431 DOI: 10.1016/j.jsb.2008.11.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Revised: 11/17/2008] [Accepted: 11/26/2008] [Indexed: 10/21/2022]
Abstract
Decorin and its associated glycosaminoglycan (GAG) side chain, dermatan sulfate (DS), play diverse roles in soft tissue formation and potentially aid in the mechanical integrity of the tissue. Deeper understanding of the distribution and orientation of the GAGs on a microscopic level may help elucidate the structure/function relationship of these important molecules. The hypothesis of the present study was that sulfated GAGs are aligned with transversely isotropic material symmetry in human medial collateral ligament (MCL) with the collagen acting as the axis of symmetry. To test the hypothesis, sulfated GAGs were visualized using transmission electron microscopy (TEM). Three orthogonal anatomical planes were examined to evaluate GAG distributions against symmetry criteria. GAG populations were differentiated using targeted enzyme digestion. Results suggest that sulfated GAGs including DS, chondroitin sulfates A and C, as well as other sub-populations assume transversely isotropic distributions in human MCL. Sulfated GAGs in the plane normal to the collagen axis were found to be isotropic with no preferred orientation. GAGs in the two planes along the collagen axis did not statistically differ and exhibited apparent bimodal distributions, favoring orthogonal distributions with over half at other angles with respect to collagen. A previously developed model, GAGSim3D, was used to interpret potential TEM artifacts. The data collected herein provide refined inputs to micro-scale models of the structure/function relationship of sulfated GAGs in soft tissues.
Collapse
Affiliation(s)
- Heath B Henninger
- Department of Bioengineering, University of Utah, 50 South Central Campus Drive, Room 2480, Salt Lake City, UT 84112, USA
| | | | | | | | | |
Collapse
|
17
|
Ciarletta P, Ben Amar M. A finite dissipative theory of temporary interfibrillar bridges in the extracellular matrix of ligaments and tendons. J R Soc Interface 2008; 6:909-24. [PMID: 19106068 DOI: 10.1098/rsif.2008.0487] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The structural integrity and the biomechanical characteristics of ligaments and tendons result from the interactions between collagenous and non-collagenous proteins (e.g. proteoglycans, PGs) in the extracellular matrix. In this paper, a dissipative theory of temporary interfibrillar bridges in the anisotropic network of collagen type I, embedded in a ground substance, is derived. The glycosaminoglycan chains of decorin are assumed to mediate interactions between fibrils, behaving as viscous structures that transmit deformations outside the collagen molecules. This approach takes into account the dissipative effects of the unfolding preceding fibrillar elongation, together with the slippage of entire fibrils and the strain-rate-dependent damage evolution of the interfibrillar bridges. Thermodynamic consistency is used to derive the constitutive equations, and the transition state theory is applied to model the rearranging properties of the interfibrillar bridges. The constitutive theory is applied to reproduce the hysteretic spectrum of the tissues, demonstrating how PGs determine damage evolution, softening and non-recoverable strains in their cyclic mechanical response. The theoretical predictions are compared with the experimental response of ligaments and tendons from referenced studies. The relevance of the proposed model in mechanobiology research is discussed, together with several applications from medical practice to bioengineering science.
Collapse
Affiliation(s)
- P Ciarletta
- Laboratoire de Physique Statistique de l'Ecole Normale Supérieure, 24 rue Lhomond, Paris Cedex 05, France.
| | | |
Collapse
|
18
|
Lujan TJ, Underwood CJ, Jacobs NT, Weiss JA. Contribution of glycosaminoglycans to viscoelastic tensile behavior of human ligament. J Appl Physiol (1985) 2008; 106:423-31. [PMID: 19074575 DOI: 10.1152/japplphysiol.90748.2008] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The viscoelastic properties of human ligament potentially guard against structural failure, yet the microstructural origins of these transient behaviors are unknown. Glycosaminoglycans (GAGs) are widely suspected to affect ligament viscoelasticity by forming molecular bridges between neighboring collagen fibrils. This study investigated whether GAGs directly affect viscoelastic material behavior in human medial collateral ligament (MCL) by using nondestructive tensile tests before and after degradation of GAGs with chondroitinase ABC (ChABC). Control and ChABC treatment (83% GAG removal) produced similar alterations to ligament viscoelasticity. This finding was consistent at different levels of collagen fiber stretch and tissue hydration. On average, stress relaxation increased after incubation by 2.2% (control) and 2.1% (ChABC), dynamic modulus increased after incubation by 3.6% (control) and 3.8% (ChABC), and phase shift increased after incubation by 8.5% (control) and 8.4% (ChABC). The changes in viscoelastic behavior after treatment were significantly more pronounced at lower clamp-to-clamp strain levels. A 10% difference in the water content of tested specimens had minor influence on ligament viscoelastic properties. The major finding of this study is that mechanical interactions between collagen fibrils and GAGs are unrelated to tissue-level viscoelastic mechanics in mature human MCL. These findings narrow the possible number of extracellular matrix molecules that have a direct contribution to ligament viscoelasticity.
Collapse
Affiliation(s)
- Trevor J Lujan
- Department of Bioengineering, University of Utah, Salt Lake City, UT 84112, USA
| | | | | | | |
Collapse
|
19
|
Raspanti M, Viola M, Forlino A, Tenni R, Gruppi C, Tira ME. Glycosaminoglycans show a specific periodic interaction with type I collagen fibrils. J Struct Biol 2008; 164:134-9. [PMID: 18664384 DOI: 10.1016/j.jsb.2008.07.001] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Revised: 06/30/2008] [Accepted: 07/03/2008] [Indexed: 11/28/2022]
Abstract
Current wisdom on intermolecular interactions in the extracellular matrix assumes that small proteoglycans bind collagen fibrils on highly specific sites via their protein core, while their carbohydrate chains interact with each other in the interfibrillar space. The present study used high-resolution scanning electron microscopy to analyse the interaction of two small leucine-rich proteoglycans and several glycosaminoglycan chains with type I collagen fibrils obtained in vitro in a controlled, cell-free environment. Our results show that most ligands directly influence the collagen fibril size and shape, and their aggregation into thicker bundles. All chondroitin sulphate/dermatan sulphate glycosaminoglycans we tested, except chondroitin 4-sulphate, bound to the fibril surface in a highly specific way and, even in the absence of any protein core, formed regular, periodic interfibrillar links resembling those of the intact proteoglycan. Only intact decorin, however, was able to organize collagen fibrils into fibres compact enough to mimic in vitro the superfibrillar organization of natural tissues. Our data indicate that multiple interaction patterns may exist in vivo, may explain why decorin- or biglycan-knockout organisms show milder effects than can be expected, and may lead to the development of better, simpler engineered biomaterials.
Collapse
Affiliation(s)
- Mario Raspanti
- Department of Human Anatomy, Insubria University, Varese, Italy.
| | | | | | | | | | | |
Collapse
|
20
|
Lujan TJ, Underwood CJ, Henninger HB, Thompson BM, Weiss JA. Effect of dermatan sulfate glycosaminoglycans on the quasi-static material properties of the human medial collateral ligament. J Orthop Res 2007; 25:894-903. [PMID: 17343278 DOI: 10.1002/jor.20351] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The glycosaminoglycan of decorin, dermatan sulfate (DS), has been suggested to contribute to the mechanical properties of soft connective tissues such as ligaments and tendons. This study investigated the mechanical function of DS in human medial collateral ligaments (MCL) using nondestructive shear and tensile material tests performed before and after targeted removal of DS with chondroitinase B (ChB). The quasi-static elastic material properties of human MCL were unchanged after DS removal. At peak deformation, tensile and shear stresses in ChB treated tissue were within 0.5% (p>0.70) and 2.0% (p>0.30) of pre-treatment values, respectively. From pre- to post-ChB treatment under tensile loading, the tensile tangent modulus went from 242+/-64 to 233+/-57 MPa (p=0.44), and tissue strain at peak deformation went from 4.3+/-0.3% to 4.4+/-0.3% (p=0.54). Tissue hysteresis was unaffected by DS removal for both tensile and shear loading. Biochemical analysis confirmed that 90% of DS was removed by ChB treatment when compared to control samples, and transmission electron microscopy (TEM) imaging further verified the degradation of DS by showing an 88% reduction (p<.001) of sulfated glycosaminoglycans in ChB treated tissue. These results demonstrate that DS in mature knee MCL tissue does not resist tensile or shear deformation under quasi-static loading conditions, challenging the theory that decorin proteoglycans contribute to the elastic material behavior of ligament.
Collapse
Affiliation(s)
- Trevor J Lujan
- Department of Bioengineering, University of Utah, 50 South Central Campus Drive, Room 2480, Salt Lake City, UT 84112, USA
| | | | | | | | | |
Collapse
|
21
|
Kalamajski S, Aspberg A, Oldberg A. The decorin sequence SYIRIADTNIT binds collagen type I. J Biol Chem 2007; 282:16062-7. [PMID: 17426031 DOI: 10.1074/jbc.m700073200] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Decorin belongs to the small leucine-rich repeat proteoglycan family, interacts with fibrillar collagens, and regulates the assembly, structure, and biomechanical properties of connective tissues. The decorin-collagen type I-binding region is located in leucine-rich repeats 5-6. Site-directed mutagenesis of this 54-residue-long collagen-binding sequence identifies Arg-207 and Asp-210 in leucine-rich repeat 6 as crucial for the binding to collagen. The synthetic peptide SYIRIADTNIT, which includes Arg-207 and Asp-210, inhibits the binding of full-length recombinant decorin to collagen in vitro. These collagen-binding amino acids are exposed on the exterior of the beta-sheet-loop structure of the leucine-rich repeat. This resembles the location of interacting residues in other leucine-rich repeat proteins.
Collapse
Affiliation(s)
- Sebastian Kalamajski
- Department of Experimental Medical Science, University of Lund, SE-221 84 Lund, Sweden
| | | | | |
Collapse
|
22
|
Henninger HB, Maas SA, Underwood CJ, Whitaker RT, Weiss JA. Spatial distribution and orientation of dermatan sulfate in human medial collateral ligament. J Struct Biol 2006; 158:33-45. [PMID: 17150374 PMCID: PMC2814165 DOI: 10.1016/j.jsb.2006.10.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Revised: 09/01/2006] [Accepted: 10/05/2006] [Indexed: 02/08/2023]
Abstract
The proteoglycan decorin and its associated glycosaminoglycan (GAG), dermatan sulfate (DS), regulate collagen fibril formation, control fibril diameter, and have been suggested to contribute to the mechanical stability and material properties of connective tissues. The spatial distribution and orientation of DS within the tissue are relevant to these mechanical roles, but measurements of length and orientation from 2D transmission electron microscopy (TEM) are prone to errors from projection. The objectives of this study were to construct a 3D geometric model of DS GAGs and collagen fibrils, and to use the model to interpret TEM measurements of the spatial orientation and length of DS GAGs in the medial collateral ligament of the human knee. DS was distinguished from other sulfated GAGs by treating tissue with chondroitinase B, an enzyme that selectively degrades DS. An image processing pipeline was developed to analyze the TEM micrographs. The 3D model of collagen and GAGs quantified the projection error in the 2D TEM measurements. Model predictions of 3D GAG orientation were highly sensitive to the assumed GAG length distribution, with the baseline input distribution of 69+/-23 nm providing the best predictions of the angle measurements from TEM micrographs. The corresponding orientation distribution for DS GAGs was maximal at orientations orthogonal to the collagen fibrils, tapering to near zero with axial alignment. Sulfated GAGs that remained after chondroitinase B treatment were preferentially aligned along the collagen fibril. DS therefore appears more likely to bridge the interfibrillar gap than non-DS GAGs. In addition to providing quantitative data for DS GAG length and orientation in the human MCL, this study demonstrates how a 3D geometric model can be used to provide a priori information for interpretation of geometric measurements from 2D micrographs.
Collapse
Affiliation(s)
- Heath B. Henninger
- Department of Bioengineering University of Utah 50 S Central Campus Drive, Rm. 2480 Salt Lake City, UT 84112
- Scientific Computing and Imaging Institute University of Utah 50 S Central Campus Drive, Rm. 3490 Salt Lake City, UT 84112
| | - Steve A. Maas
- Department of Bioengineering University of Utah 50 S Central Campus Drive, Rm. 2480 Salt Lake City, UT 84112
- Scientific Computing and Imaging Institute University of Utah 50 S Central Campus Drive, Rm. 3490 Salt Lake City, UT 84112
| | - Clayton J. Underwood
- Department of Bioengineering University of Utah 50 S Central Campus Drive, Rm. 2480 Salt Lake City, UT 84112
- Scientific Computing and Imaging Institute University of Utah 50 S Central Campus Drive, Rm. 3490 Salt Lake City, UT 84112
| | - Ross T. Whitaker
- Scientific Computing and Imaging Institute University of Utah 50 S Central Campus Drive, Rm. 3490 Salt Lake City, UT 84112
| | - Jeffrey A. Weiss
- Department of Bioengineering University of Utah 50 S Central Campus Drive, Rm. 2480 Salt Lake City, UT 84112
- Scientific Computing and Imaging Institute University of Utah 50 S Central Campus Drive, Rm. 3490 Salt Lake City, UT 84112
- Department of Orthopaedics University of Utah 30 North 1900 East, Rm. 3B165 Salt Lake City, UT 84132
| |
Collapse
|
23
|
|