1
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Pratt SJP, Plunkett CM, Kuzu G, Trinh T, Barbara J, Choconta P, Quackenbush D, Huynh T, Smith A, Barnes SW, New J, Pierce J, Walker JR, Mainquist J, King FJ, Elliott J, Hammack S, Decker RS. A high throughput cell stretch device for investigating mechanobiology in vitro. APL Bioeng 2024; 8:026129. [PMID: 38938688 PMCID: PMC11210978 DOI: 10.1063/5.0206852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Accepted: 05/31/2024] [Indexed: 06/29/2024] Open
Abstract
Mechanobiology is a rapidly advancing field, with growing evidence that mechanical signaling plays key roles in health and disease. To accelerate mechanobiology-based drug discovery, novel in vitro systems are needed that enable mechanical perturbation of cells in a format amenable to high throughput screening. Here, both a mechanical stretch device and 192-well silicone flexible linear stretch plate were designed and fabricated to meet high throughput technology needs for cell stretch-based applications. To demonstrate the utility of the stretch plate in automation and screening, cell dispensing, liquid handling, high content imaging, and high throughput sequencing platforms were employed. Using this system, an assay was developed as a biological validation and proof-of-concept readout for screening. A mechano-transcriptional stretch response was characterized using focused gene expression profiling measured by RNA-mediated oligonucleotide Annealing, Selection, and Ligation with Next-Gen sequencing. Using articular chondrocytes, a gene expression signature containing stretch responsive genes relevant to cartilage homeostasis and disease was identified. The possibility for integration of other stretch sensitive cell types (e.g., cardiovascular, airway, bladder, gut, and musculoskeletal), in combination with alternative phenotypic readouts (e.g., protein expression, proliferation, or spatial alignment), broadens the scope of high throughput stretch and allows for wider adoption by the research community. This high throughput mechanical stress device fills an unmet need in phenotypic screening technology to support drug discovery in mechanobiology-based disease areas.
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Affiliation(s)
- Stephen J. P. Pratt
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | | | - Guray Kuzu
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Ton Trinh
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Joshua Barbara
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Paula Choconta
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Doug Quackenbush
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Truc Huynh
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Anders Smith
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - S. Whitney Barnes
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Joel New
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - James Pierce
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - John R. Walker
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - James Mainquist
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Frederick J. King
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Jimmy Elliott
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Scott Hammack
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
| | - Rebekah S. Decker
- Novartis, Biomedical Research 10675 John Jay Hopkins Dr, San Diego, California 92121, USA
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2
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Franklin M, Sperry M, Phillips E, Granquist E, Marcolongo M, Winkelstein BA. Painful temporomandibular joint overloading induces structural remodeling in the pericellular matrix of that joint's chondrocytes. J Orthop Res 2022; 40:348-358. [PMID: 33830541 PMCID: PMC8497636 DOI: 10.1002/jor.25050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 03/01/2021] [Accepted: 03/24/2021] [Indexed: 02/04/2023]
Abstract
Mechanical stress to the temporomandibular joint (TMJ) is an important factor in cartilage degeneration, with both clinical and preclinical studies suggesting that repeated TMJ overloading could contribute to pain, inflammation, and/or structural damage in the joint. However, the relationship between pain severity and early signs of cartilage matrix microstructural dysregulation is not understood, limiting the advancement of diagnoses and treatments for temporomandibular joint-osteoarthritis (TMJ-OA). Changes in the pericellular matrix (PCM) surrounding chondrocytes may be early indicators of OA. A rat model of TMJ pain induced by repeated jaw loading (1 h/day for 7 days) was used to compare the extent of PCM modulation for different loading magnitudes with distinct pain profiles (3.5N-persistent pain, 2N-resolving pain, or unloaded controls-no pain) and macrostructural changes previously indicated by Mankin scoring. Expression of PCM structural molecules, collagen VI and aggrecan NITEGE neo-epitope, were evaluated at Day 15 by immunohistochemistry within TMJ fibrocartilage and compared between pain conditions. Pericellular collagen VI levels increased at Day 15 in both the 2N (p = 0.003) and 3.5N (p = 0.042) conditions compared to unloaded controls. PCM width expanded to a similar extent for both loading conditions at Day 15 (2N, p < 0.001; 3.5N, p = 0.002). Neo-epitope expression increased in the 3.5N group over levels in the 2N group (p = 0.041), indicating pericellular changes that were not identified in the same groups by Mankin scoring of the pericellular region. Although remodeling occurs in both pain conditions, the presence of pericellular catabolic neo-epitopes may be involved in the macrostructural changes and behavioral sensitivity observed in persistent TMJ pain.
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Affiliation(s)
- Melissa Franklin
- School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, PA, 19104
| | - Megan Sperry
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, 19104,Corresponding Author(s): Megan Sperry, PhD, Wyss Institute at Harvard University, 3 Blackfan Circle, Boston, MA 02115, , 978-387-3763
| | - Evan Phillips
- Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104
| | - Eric Granquist
- Oral & Maxillofacial Surgery, University of Pennsylvania, Philadelphia, PA 19104
| | - Michele Marcolongo
- Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104
| | - Beth A. Winkelstein
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, 19104
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3
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Clark JN, Tavana S, Clark B, Briggs T, Jeffers JRT, Hansen U. High resolution three-dimensional strain measurements in human articular cartilage. J Mech Behav Biomed Mater 2021; 124:104806. [PMID: 34509906 DOI: 10.1016/j.jmbbm.2021.104806] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 06/21/2021] [Accepted: 08/28/2021] [Indexed: 12/21/2022]
Abstract
An unresolved challenge in osteoarthritis research is characterising the localised intra-tissue mechanical response of articular cartilage. The aim of this study was to explore whether laboratory micro-computed tomography (micro-CT) and digital volume correlation (DVC) permit non-destructive quantification of three-dimensional (3D) strain fields in human articular cartilage. Human articular cartilage specimens were harvested from the knee, mounted into a loading device and imaged in the unloaded and loaded states using a micro-CT scanner. Strain was measured throughout the cartilage volume using the micro-CT image data and DVC analysis. The volumetric DVC-measured strain was within 5% of the known applied strain. Variation in strain distribution between the superficial, middle and deep zones was observed, consistent with the different architecture of the material in these locations. These results indicate DVC method may be suitable for calculating strain in human articular cartilage.
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Affiliation(s)
- Jeffrey N Clark
- Department of Mechanical Engineering, Imperial College London, London, UK
| | - Saman Tavana
- Department of Mechanical Engineering, Imperial College London, London, UK
| | - Brett Clark
- Imaging and Analysis Centre, Natural History Museum London, London, UK
| | - Tom Briggs
- Department of Mechanical Engineering, Imperial College London, London, UK
| | | | - Ulrich Hansen
- Department of Mechanical Engineering, Imperial College London, London, UK
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4
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He Y, Yocum L, Alexander PG, Jurczak MJ, Lin H. Urolithin A Protects Chondrocytes From Mechanical Overloading-Induced Injuries. Front Pharmacol 2021; 12:703847. [PMID: 34220525 PMCID: PMC8245698 DOI: 10.3389/fphar.2021.703847] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/04/2021] [Indexed: 01/10/2023] Open
Abstract
Physiological mechanical stimulation has been shown to promote chondrogenesis, but excessive mechanical loading results in cartilage degradation. Currently, the underlying mechanotransduction pathways in the context of physiological and injurious loading are not fully understood. In this study, we aim to identify the critical factors that dictate chondrocyte response to mechanical overloading, as well as to develop therapeutics that protect chondrocytes from mechanical injuries. Specifically, human chondrocytes were loaded in hyaluronic hydrogel and then subjected to dynamic compressive loading under 5% (DL-5% group) or 25% strain (DL-25% group). Compared to static culture and DL-5%, DL-25% reduced cartilage matrix formation from chondrocytes, which was accompanied by the increased senescence level, as revealed by higher expression of p21, p53, and senescence-associated beta-galactosidase (SA-β-Gal). Interestingly, mitophagy was suppressed by DL-25%, suggesting a possible role for the restoration mitophagy in reducing cartilage degeneration with mechanical overloading. Next, we treated the mechanically overloaded samples (DL-25%) with Urolithin A (UA), a natural metabolite previously shown to enhance mitophagy in other cell types. qRT-PCR, histology, and immunostaining results confirmed that UA treatment significantly increased the quantity and quality of cartilage matrix deposition. Interestingly, UA also suppressed the senescence level induced by mechanical overloading, demonstrating its senomorphic potential. Mechanistic analysis confirmed that UA functioned partially by enhancing mitophagy. In summary, our results show that mechanical overloading results in cartilage degradation partially through the impairment of mitophagy. This study also identifies UA's novel use as a compound that can protect chondrocytes from mechanical injuries, supporting high-quality cartilage formation/maintenance.
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Affiliation(s)
- Yuchen He
- Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.,Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, China
| | - Lauren Yocum
- Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Peter G Alexander
- Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Michael J Jurczak
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Hang Lin
- Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.,Department of Bioengineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, PA, United States.,McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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5
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Komeili A, Otoo BS, Abusara Z, Sibole S, Federico S, Herzog W. Chondrocyte Deformations Under Mild Dynamic Loading Conditions. Ann Biomed Eng 2020; 49:846-857. [PMID: 32959133 DOI: 10.1007/s10439-020-02615-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 09/08/2020] [Indexed: 12/14/2022]
Abstract
Dynamic deformation of chondrocytes are associated with cell mechanotransduction and thus may offer a new understanding of the mechanobiology of articular cartilage. Despite extensive research on chondrocyte deformations for static conditions, work for dynamic conditions remains rare. However, it is these dynamic conditions that articular cartilage in joints are exposed to everyday, and that seem to promote biological signaling in chondrocytes. Therefore, the objective of this study was to develop an experimental technique to determine the in situ deformations of chondrocytes when the cartilage is dynamically compressed. We hypothesized that dynamic deformations of chondrocytes vastly differ from those observed under steady-state static strain conditions. Real-time chondrocyte geometry was reconstructed at 10, 15, and 20% compression during ramp compressions with 20% ultimate strain, applied at a strain rate of 0.2% s-1, followed by stress relaxation. Dynamic compressive chondrocyte deformations were non-linear as a function of nominal strain, with large deformations in the early and small deformations in the late part of compression. Early compression (up to about 10%) was associated with chondrocyte volume loss, while late compression (> ~ 10%) was associated with cell deformation but minimal volume loss. Force continued to decrease for 5 min in the stress-relaxation phase, while chondrocyte shape/volume remained unaltered after the first minute of stress-relaxation.
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Affiliation(s)
- Amin Komeili
- Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada.,School of Engineering, University of Guelph, 50 Stone Rd E, Guelph, N1G 2W1, ON, Canada
| | - Baaba Sekyiwaa Otoo
- Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
| | - Ziad Abusara
- Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada.,Advanced Imaging and Histopathology Core, Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Qatar Foundation, P.O. Box 34110, Doha, Qatar
| | - Scott Sibole
- Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
| | - Salvatore Federico
- Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada.,Department of Mechanical and Manufacturing Engineering, The University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
| | - Walter Herzog
- Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada. .,Biomechanics Laboratory, School of Sports, Federal University of Santa Catarina, Florianopolis, SC, Brazil.
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6
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Workman J, McGlashan S, Thambyah A. Macroscopically healthy articular cartilage with fibrillar-scale early tissue degeneration subject to impact loading results in greater extent of cell-death. J Mech Behav Biomed Mater 2020; 112:104043. [PMID: 32861062 DOI: 10.1016/j.jmbbm.2020.104043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 07/26/2020] [Accepted: 08/16/2020] [Indexed: 12/01/2022]
Abstract
From previous investigations it has been shown that there exists healthy-appearing articular cartilage that contains collagen fibril network destructuring. It is hypothesised that such sub-micron scale destructuring not only presents an increased vulnerability to tissue scale damage following impact loading, but an increase in cell death as well. Cartilage-on-bone blocks from 12 patellae, six healthy (G0) and the other six with sub-micron fibrillar destructuring (G1), were obtained and subject to 2.3 J impact loading. Two sets of sub-samples were obtained for each block tested. One set was used to examine for the live/dead cell response using calcein-AM and propidium iodide staining, imaged with confocal microscopy. The tissue microstructural matrix was imaged from the other matched set, unstained and in its fully hydrated state, using differential interference contrast optical light microscopy. High speed imaging of the impact was used to calculate the velocity changes or coefficient of restitution (COR) and used as a proxy of energy that the tissue absorbed. A previously defined tissue matrix damage score was used to quantify the extent of fracturing and cracking in the matrix. The cell death (PCD) was counted and presented as a percentage against all cells live plus dead. The energy absorbed was 36.5% higher in G1 than in G0 (p = 0.034). However, the damage score and PCD of samples in the G1 group was much larger than the G0 group, ~300% and 161% respectively. Microscopy showed that cell death is associated to both matrix compaction and further fibrillar destructuring from the ECM to the territorial matrix regions of the chondron. Following impact loading, cartilage tissue that appears normal but contains sub-micron fibrillar matrix destructuring responds with significantly increased cell death.
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Affiliation(s)
- J Workman
- University of Auckland, Faculty of Engineering, 2-4 Park Ave, Grafton, Auckland, 1023, New Zealand.
| | - S McGlashan
- University of Auckland, Faculty of Medical and Health Sciences, 85 Park Road, Grafton, 1023, Auckland, New Zealand
| | - A Thambyah
- University of Auckland, Faculty of Engineering, 2-4 Park Ave, Grafton, Auckland, 1023, New Zealand
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7
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Chery DR, Han B, Li Q, Zhou Y, Heo SJ, Kwok B, Chandrasekaran P, Wang C, Qin L, Lu XL, Kong D, Enomoto-Iwamoto M, Mauck RL, Han L. Early changes in cartilage pericellular matrix micromechanobiology portend the onset of post-traumatic osteoarthritis. Acta Biomater 2020; 111:267-278. [PMID: 32428685 DOI: 10.1016/j.actbio.2020.05.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 05/02/2020] [Accepted: 05/05/2020] [Indexed: 12/14/2022]
Abstract
The pericellular matrix (PCM) of cartilage is a structurally distinctive microdomain surrounding each chondrocyte, and is pivotal to cell homeostasis and cell-matrix interactions in healthy tissue. This study queried if the PCM is the initiation point for disease or a casualty of more widespread matrix degeneration. To address this question, we queried the mechanical properties of the PCM and chondrocyte mechanoresponsivity with the development of post-traumatic osteoarthritis (PTOA). To do so, we integrated Kawamoto's film-assisted cryo-sectioning with immunofluorescence-guided AFM nanomechanical mapping, and quantified the microscale modulus of murine cartilage PCM and further-removed extracellular matrix. Using the destabilization of the medial meniscus (DMM) murine model of PTOA, we show that decreases in PCM micromechanics are apparent as early as 3 days after injury, and that this precedes changes in the bulk ECM properties and overt indications of cartilage damage. We also show that, as a consequence of altered PCM properties, calcium mobilization by chondrocytes in response to mechanical challenge (hypo-osmotic stress) is significantly disrupted. These aberrant changes in chondrocyte micromechanobiology as a consequence of DMM could be partially blocked by early inhibition of PCM remodeling. Collectively, these results suggest that changes in PCM micromechanobiology are leading indicators of the initiation of PTOA, and that disease originates in the cartilage PCM. This insight will direct the development of early detection methods, as well as small molecule-based therapies that can stop early aberrant remodeling in this critical cartilage microdomain to slow or reverse disease progression. STATEMENT OF SIGNIFICANCE: Post-traumatic osteoarthritis (PTOA) is one prevalent musculoskeletal disease that afflicts young adults, and there are no effective strategies for early detection or intervention. This study identifies that the reduction of cartilage pericellular matrix (PCM) micromodulus is one of the earliest events in the initiation of PTOA, which, in turn, impairs the mechanosensitive activities of chondrocytes, contributing to the vicious loop of cartilage degeneration. Rescuing the integrity of PCM has the potential to restore normal chondrocyte mechanosensitive homeostasis and to prevent further degradation of cartilage. Our findings enable the development of early OA detection methods targeting changes in the PCM, and treatment strategies that can stop early aberrant remodeling in this critical microdomain to slow or reverse disease progression.
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8
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Wang C, Brisson BK, Terajima M, Li Q, Hoxha K, Han B, Goldberg AM, Sherry Liu X, Marcolongo MS, Enomoto-Iwamoto M, Yamauchi M, Volk SW, Han L. Type III collagen is a key regulator of the collagen fibrillar structure and biomechanics of articular cartilage and meniscus. Matrix Biol 2019; 85-86:47-67. [PMID: 31655293 DOI: 10.1016/j.matbio.2019.10.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 10/15/2019] [Accepted: 10/16/2019] [Indexed: 02/07/2023]
Abstract
Despite the fact that type III collagen is the second most abundant collagen type in the body, its contribution to the physiologic maintenance and repair of skeletal tissues remains poorly understood. This study queried the role of type III collagen in the structure and biomechanical functions of two structurally distinctive tissues in the knee joint, type II collagen-rich articular cartilage and type I collagen-dominated meniscus. Integrating outcomes from atomic force microscopy-based nanomechanical tests, collagen fibril nanostructural analysis, collagen cross-link analysis and histology, we elucidated the impact of type III collagen haplodeficiency on the morphology, nanostructure and biomechanical properties of articular cartilage and meniscus in Col3a1+/- mice. Reduction of type III collagen leads to increased heterogeneity and mean thickness of collagen fibril diameter, as well as reduced modulus in both tissues, and these effects became more pronounced with skeletal maturation. These data suggest a crucial role of type III collagen in mediating fibril assembly and biomechanical functions of both articular cartilage and meniscus during post-natal growth. In articular cartilage, type III collagen has a marked contribution to the micromechanics of the pericellular matrix, indicating a potential role in mediating the early stage of type II collagen fibrillogenesis and chondrocyte mechanotransduction. In both tissues, reduction of type III collagen leads to decrease in tissue modulus despite the increase in collagen cross-linking. This suggests that the disruption of matrix structure due to type III collagen deficiency outweighs the stiffening of collagen fibrils by increased cross-linking, leading to a net negative impact on tissue modulus. Collectively, this study is the first to highlight the crucial structural role of type III collagen in both articular cartilage and meniscus extracellular matrices. We expect these results to expand our understanding of type III collagen across various tissue types, and to uncover critical molecular components of the microniche for regenerative strategies targeting articular cartilage and meniscus repair.
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Affiliation(s)
- Chao Wang
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA 19104, United States
| | - Becky K Brisson
- Department of Clinical Sciences and Advanced Medicine, University of Pennsylvania, School of Veterinary Medicine, Philadelphia, PA, 19104, United States
| | - Masahiko Terajima
- Division of Oral and Craniofacial Health Sciences, University of North Carolina, Chapel Hill, NC, 27599, United States
| | - Qing Li
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA 19104, United States
| | - Kevt'her Hoxha
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA 19104, United States
| | - Biao Han
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA 19104, United States
| | - Abby M Goldberg
- Department of Clinical Sciences and Advanced Medicine, University of Pennsylvania, School of Veterinary Medicine, Philadelphia, PA, 19104, United States
| | - X Sherry Liu
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, United States
| | - Michele S Marcolongo
- Department of Materials Science and Engineering, Drexel University, Philadelphia, PA, 19104, United States
| | - Motomi Enomoto-Iwamoto
- Department of Orthopaedics, School of Medicine, University of Maryland, Baltimore, MD, 21201, United States
| | - Mitsuo Yamauchi
- Division of Oral and Craniofacial Health Sciences, University of North Carolina, Chapel Hill, NC, 27599, United States
| | - Susan W Volk
- Department of Clinical Sciences and Advanced Medicine, University of Pennsylvania, School of Veterinary Medicine, Philadelphia, PA, 19104, United States.
| | - Lin Han
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA 19104, United States.
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9
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Fu S, Thompson C, Ali A, Wang W, Chapple J, Mitchison H, Beales P, Wann A, Knight M. Mechanical loading inhibits cartilage inflammatory signalling via an HDAC6 and IFT-dependent mechanism regulating primary cilia elongation. Osteoarthritis Cartilage 2019; 27:1064-1074. [PMID: 30922983 PMCID: PMC6593179 DOI: 10.1016/j.joca.2019.03.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 03/04/2019] [Accepted: 03/16/2019] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Physiological mechanical loading reduces inflammatory signalling in numerous cell types including articular chondrocytes however the mechanism responsible remains unclear. This study investigates the role of chondrocyte primary cilia and associated intraflagellar transport (IFT) in the mechanical regulation of interleukin-1β (IL-1β) signalling. DESIGN Isolated chondrocytes and cartilage explants were subjected to cyclic mechanical loading in the presence and absence of the cytokine IL-1β. Nitric oxide (NO) and prostaglandin E2 (PGE2) release were used to monitor IL-1β signalling whilst Sulphated glycosaminoglycan (sGAG) release provided measurement of cartilage degradation. Measurements were made of HDAC6 activity and tubulin polymerisation and acetylation. Effects on primary cilia were monitored by confocal and super resolution microscopy. Involvement of IFT was analysed using ORPK cells with hypomorphic mutation of IFT88. RESULTS Mechanical loading suppressed NO and PGE2 release and prevented cartilage degradation. Loading activated HDAC6 and disrupted tubulin acetylation and cilia elongation induced by IL-1β. HDAC6 inhibition with tubacin blocked the anti-inflammatory effects of loading and restored tubulin acetylation and cilia elongation. Hypomorphic mutation of IFT88 reduced IL-1β signalling and abolished the anti-inflammatory effects of loading indicating the mechanism is IFT-dependent. Loading reduced the pool of non-polymerised tubulin which was replicated by taxol which also mimicked the anti-inflammatory effects of mechanical loading and prevented cilia elongation. CONCLUSIONS This study reveals that mechanical loading suppresses inflammatory signalling, partially dependent on IFT, by activation of HDAC6 and post transcriptional modulation of tubulin.
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Affiliation(s)
- S. Fu
- Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary University of London, UK
| | - C.L. Thompson
- Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary University of London, UK,Address correspondence and reprint requests to: C. L. Thompson, School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS, UK. Tel: 44-20-7882-3603.
| | - A. Ali
- Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary University of London, UK
| | - W. Wang
- Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary University of London, UK
| | - J.P. Chapple
- Department of Endocrinology, William Harvey Research Centre, Queen Mary University of London, UK
| | - H.M. Mitchison
- Institute of Child Health, University College of London, UK
| | - P.L. Beales
- Institute of Child Health, University College of London, UK
| | - A.K.T. Wann
- Kennedy Institute of Rheumatology, University of Oxford, UK
| | - M.M. Knight
- Institute of Bioengineering, School of Engineering and Materials Science, Queen Mary University of London, UK
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10
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Phillips ER, Haislup BD, Bertha N, Lefchak M, Sincavage J, Prudnikova K, Shallop B, Mulcahey MK, Marcolongo MS. Biomimetic proteoglycans diffuse throughout articular cartilage and localize within the pericellular matrix. J Biomed Mater Res A 2019; 107:1977-1987. [DOI: 10.1002/jbm.a.36710] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 02/08/2019] [Accepted: 04/25/2019] [Indexed: 12/16/2022]
Affiliation(s)
- Evan R. Phillips
- Department of Materials Science and Engineering, College of Engineering Drexel University Philadelphia Pennsylvania
| | | | - Nicholas Bertha
- College of Medicine Drexel University Philadelphia Pennsylvania
| | - Maria Lefchak
- Department of Materials Science and Engineering, College of Engineering Drexel University Philadelphia Pennsylvania
| | - Joseph Sincavage
- School of Biomedical Engineering Drexel University Philadelphia Pennsylvania
| | - Katsiaryna Prudnikova
- Department of Materials Science and Engineering, College of Engineering Drexel University Philadelphia Pennsylvania
| | - Brandon Shallop
- Department of Orthopaedic Surgery Drexel University College of Medicine/Hahnemann University Hospital Philadelphia Pennsylvania
| | - Mary K. Mulcahey
- Department of Orthopaedic Surgery Tulane University School of Medicine New Orleans Louisiana
| | - Michele S. Marcolongo
- Department of Materials Science and Engineering, College of Engineering Drexel University Philadelphia Pennsylvania
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11
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Sianati S, Kurumlian A, Bailey E, Poole K. Analysis of Mechanically Activated Ion Channels at the Cell-Substrate Interface: Combining Pillar Arrays and Whole-Cell Patch-Clamp. Front Bioeng Biotechnol 2019; 7:47. [PMID: 30984749 PMCID: PMC6448047 DOI: 10.3389/fbioe.2019.00047] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Accepted: 02/28/2019] [Indexed: 12/14/2022] Open
Abstract
Ionic currents can be evoked by mechanical inputs applied directly at the cell-substrate interface. These ionic currents are mediated by mechanically activated ion channels, where the open probability increases with increasing mechanical input. In order to study mechanically activated ion channels directly at the interface between cells and their environment, we have developed a technique to simultaneously monitor ion channel activity whilst stimuli are applied via displacement of cell-substrate contacts. This technique utilizes whole-cell patch-clamp electrophysiology and elastomeric pillar arrays, it is quantitative and appropriate for studying channels that respond to stimuli that are propagated to an adherent cell via the physical substrate. The mammalian channels PIEZO1, PIEZO2 have been shown to be activated by substrate deflections, using this technique. In addition, TRPV4 mediated currents can be evoked by substrate deflections, in contrast to alternate stimulation methods such as membrane stretch or cellular indentation. The deflections applied at cell-substrate points mimic the magnitude of physical stimuli that impact cells in situ.
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Affiliation(s)
- Setareh Sianati
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia.,Cellular and Systems Physiology, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Anie Kurumlian
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia.,Cellular and Systems Physiology, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Evan Bailey
- Cellular and Systems Physiology, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Kate Poole
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia.,Cellular and Systems Physiology, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
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12
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Komeili A, Abusara Z, Federico S, Herzog W. A compression system for studying depth-dependent mechanical properties of articular cartilage under dynamic loading conditions. Med Eng Phys 2018; 60:103-108. [PMID: 30061065 DOI: 10.1016/j.medengphy.2018.07.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 06/30/2018] [Accepted: 07/15/2018] [Indexed: 10/28/2022]
Abstract
The biological activities of chondrocytes are influenced by the mechanical characteristics of their environment. The overall real-time mechanical response of cartilage has been investigated earlier. However, the instantaneous local mechano-biology of cartilage has not been investigated in detail under dynamic loading conditions. In order to address this gap in the literature, we designed a compression testing device and implemented a dual photon microscopy technique with the goal of measuring local mechanical and biological responses of articular cartilage under dynamic loading conditions. The details of the compression system and results of a pilot study are presented here. A 15% ramp compression at a rate of 0.003/s with a subsequent stress relaxation phase was applied to the cartilage explant samples. The extra cellular matrix was imaged throughout the entire thickness of the cartilage sample, and local tissue strains were measured during the compression and relaxation phase. The axial compressive strains in the middle and superficial zones of cartilage were observed to increase during the relaxation phase: this was a new finding, suggesting the importance of further investigations on the real-time local behavior of cartilage. The compression system showed promising results for investigating the dynamic, real-time mechanical response of articular cartilage, and can now be used to reveal the instantaneous mechanical and biological responses of chondrocytes in response to dynamic loading conditions.
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Affiliation(s)
- Amin Komeili
- Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, Calgary, Canada 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada
| | - Ziad Abusara
- Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, Calgary, Canada 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada
| | - Salvatore Federico
- Department of Mechanical and Manufacturing Engineering, The University of Calgary, Calgary, Canada 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada; Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, Calgary, Canada 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada
| | - Walter Herzog
- Human Performance Laboratory, Faculty of Kinesiology, The University of Calgary, Calgary, Canada 2500 University Drive NW, Calgary, Alberta, T2N 1N4, Canada.
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13
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Kotelsky A, Woo CW, Delgadillo LF, Richards MS, Buckley MR. An Alternative Method to Characterize the Quasi-Static, Nonlinear Material Properties of Murine Articular Cartilage. J Biomech Eng 2018; 140:2657496. [PMID: 29049670 DOI: 10.1115/1.4038147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Indexed: 11/08/2022]
Abstract
With the onset and progression of osteoarthritis (OA), articular cartilage (AC) mechanical properties are altered. These alterations can serve as an objective measure of tissue degradation. Although the mouse is a common and useful animal model for studying OA, it is extremely challenging to measure the mechanical properties of murine AC due to its small size (thickness < 50 μm). In this study, we developed novel and direct approach to independently quantify two quasi-static mechanical properties of mouse AC: the load-dependent (nonlinear) solid matrix Young's modulus (E) and drained Poisson's ratio (ν). The technique involves confocal microscope-based multiaxial strain mapping of compressed, intact murine AC followed by inverse finite element analysis (iFEA) to determine E and ν. Importantly, this approach yields estimates of E and ν that are independent of the initial guesses used for iterative optimization. As a proof of concept, mechanical properties of AC on the medial femoral condyles of wild-type mice were obtained for both trypsin-treated and control specimens. After proteolytic tissue degradation induced through trypsin treatment, a dramatic decrease in E was observed (compared to controls) at each of the three tested loading conditions. A significant decrease in ν due to trypsin digestion was also detected. These data indicate that the method developed in this study may serve as a valuable tool for comparative studies evaluating factors involved in OA pathogenesis using experimentally induced mouse OA models.
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Affiliation(s)
- Alexander Kotelsky
- Department of Biomedical Engineering, University of Rochester, 207 Goergen Hall, Box 270168, Rochester, NY 14627 e-mail:
| | - Chandler W Woo
- Department of Biomedical Engineering, University of Rochester, 207 Goergen Hall, Box 270168, Rochester, NY 14627 e-mail:
| | - Luis F Delgadillo
- Department of Biomedical Engineering, University of Rochester, 207 Goergen Hall, Box 270168, Rochester, NY 14627 e-mail:
| | - Michael S Richards
- Department of Surgery, School of Medicine and Dentistry, University of Rochester Medical Center, 601 Elmwood Avenue, Rm 2.4153, Rochester, NY 14627 e-mail:
| | - Mark R Buckley
- Department of Biomedical Engineering, University of Rochester, 207 Goergen Hall, Box 270168, Rochester, NY 14627 e-mail:
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14
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Moo EK, Sibole SC, Han SK, Herzog W. Three-dimensional micro-scale strain mapping in living biological soft tissues. Acta Biomater 2018; 70:260-269. [PMID: 29425715 DOI: 10.1016/j.actbio.2018.01.048] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 01/16/2018] [Accepted: 01/30/2018] [Indexed: 10/18/2022]
Abstract
Non-invasive characterization of the mechanical micro-environment surrounding cells in biological tissues at multiple length scales is important for the understanding of the role of mechanics in regulating the biosynthesis and phenotype of cells. However, there is a lack of imaging methods that allow for characterization of the cell micro-environment in three-dimensional (3D) space. The aims of this study were (i) to develop a multi-photon laser microscopy protocol capable of imprinting 3D grid lines onto living tissue at a high spatial resolution, and (ii) to develop image processing software capable of analyzing the resulting microscopic images and performing high resolution 3D strain analyses. Using articular cartilage as the biological tissue of interest, we present a novel two-photon excitation imaging technique for measuring the internal 3D kinematics in intact cartilage at sub-micrometer resolution, spanning length scales from the tissue to the cell level. Using custom image processing software, we provide accurate and robust 3D micro-strain analysis that allows for detailed qualitative and quantitative assessment of the 3D tissue kinematics. This novel technique preserves tissue structural integrity post-scanning, therefore allowing for multiple strain measurements at different time points in the same specimen. The proposed technique is versatile and opens doors for experimental and theoretical investigations on the relationship between tissue deformation and cell biosynthesis. Studies of this nature may enhance our understanding of the mechanisms underlying cell mechano-transduction, and thus, adaptation and degeneration of soft connective tissues. STATEMENT OF SIGNIFICANCE We presented a novel two-photon excitation imaging technique for measuring the internal 3D kinematics in intact cartilage at sub-micrometer resolution, spanning from tissue length scale to cellular length scale. Using a custom image processing software (lsmgridtrack), we provide accurate and robust micro-strain analysis that allowed for detailed qualitative and quantitative assessment of the 3D tissue kinematics. The approach presented here can also be applied to other biological tissues such as meniscus and annulus fibrosus, as well as tissue-engineered tissues for the characterization of their mechanical properties. This imaging technique opens doors for experimental and theoretical investigation on the relationship between tissue deformation and cell biosynthesis. Studies of this nature may enhance our understanding of the mechanisms underlying cell mechano-transduction, and thus, adaptation and degeneration of soft connective tissues.
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15
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Xia Y, Darling EM, Herzog W. Functional properties of chondrocytes and articular cartilage using optical imaging to scanning probe microscopy. J Orthop Res 2018; 36:620-631. [PMID: 28975657 PMCID: PMC5839958 DOI: 10.1002/jor.23757] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 09/20/2017] [Indexed: 02/04/2023]
Abstract
Mature chondrocytes in adult articular cartilage vary in number, size, and shape, depending on their depth in the tissue, location in the joint, and source species. Chondrocytes are the primary structural, functional, and metabolic unit in articular cartilage, the loss of which will induce fatigue to the extracellular matrix (ECM), eventually leading to failure of the cartilage and impairment of the joint as a whole. This brief review focuses on the functional and biomechanical studies of chondrocytes and articular cartilage, using microscopic imaging from optical microscopies to scanning probe microscopy. Three topics are covered in this review, including the functional studies of chondrons by optical imaging (unpolarized and polarized light and infrared light, two-photon excitation microscopy), the probing of chondrocytes and cartilage directly using microscale measurement techniques, and different imaging approaches that can measure chondrocyte mechanics and chondrocyte biological signaling under in situ and in vivo environments. Technical advancement in chondrocyte research during recent years has enabled new ways to study the biomechanical and functional properties of these cells and cartilage. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:620-631, 2018.
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Affiliation(s)
- Yang Xia
- Dept of Physics and Center for Biomedical Research, Oakland University, Rochester, MI 48309, USA
| | - Eric M. Darling
- Dept of Molecular Pharmacology, Physiology, and Biotechnology, School of Engineering, Dept of Orthopaedics, Center for Biomedical Engineering, Brown University, Providence, RI 02912, USA
| | - Walter Herzog
- Faculties of Kinesiology, Engineering and Medicine, University of Calgary, AB T2T 1N4, Canada
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16
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Lv M, Zhou Y, Chen X, Han L, Wang L, Lu XL. Calcium signaling of in situ chondrocytes in articular cartilage under compressive loading: Roles of calcium sources and cell membrane ion channels. J Orthop Res 2018; 36:730-738. [PMID: 28980722 PMCID: PMC5839963 DOI: 10.1002/jor.23768] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 09/22/2017] [Indexed: 02/04/2023]
Abstract
Mechanical loading on articular cartilage can induce many physical and chemical stimuli on chondrocytes residing in the extracellular matrix (ECM). Intracellular calcium ([Ca2+ ]i ) signaling is among the earliest responses of chondrocytes to physical stimuli, but the [Ca2+ ]i signaling of in situ chondrocytes in loaded cartilage is not fully understood due to the technical challenges in [Ca2+ ]i imaging of chondrocytes in a deforming ECM. This study developed a novel bi-directional microscopy loading device that enables the record of transient [Ca2+ ]i responses of in situ chondrocytes in loaded cartilage. It was found that compressive loading significantly promoted [Ca2+ ]i signaling in chondrocytes with faster [Ca2+ ]i oscillations in comparison to the non-loaded cartilage. Seven [Ca2+ ]i signaling pathways were further investigated by treating the cartilage with antagonists prior to and/or during the loading. Removal of extracellular Ca2+ ions completely abolished the [Ca2+ ]i responses of in situ chondrocytes, suggesting the indispensable role of extracellular Ca2+ sources in initiating the [Ca2+ ]i signaling in chondrocytes. Depletion of intracellular Ca2+ stores, inhibition of PLC-IP3 pathway, and block of purinergic receptors on plasma membrane led to significant reduction in the responsive rate of cells. Three types of ion channels that are regulated by different physical signals, TRPV4 (osmotic and mechanical stress), T-type VGCCs (electrical potential), and mechanical sensitive ion channels (mechanical loading) all demonstrated critical roles in controlling the [Ca2+ ]i responses of in situ chondrocyte in the loaded cartilage. This study provided new knowledge about the [Ca2+ ]i signaling and mechanobiology of chondrocytes in its natural residing environment. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:730-738, 2018.
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Affiliation(s)
- Mengxi Lv
- Department of Mechanical Engineering, University of Delaware, Newark, DE 19716
| | - Yilu Zhou
- Department of Mechanical Engineering, University of Delaware, Newark, DE 19716
| | - Xingyu Chen
- Department of Mechanical Engineering, University of Delaware, Newark, DE 19716
| | - Lin Han
- School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, PA 19104
| | - Liyun Wang
- Department of Mechanical Engineering, University of Delaware, Newark, DE 19716
| | - X Lucas Lu
- Department of Mechanical Engineering, University of Delaware, Newark, DE 19716,Corresponding Author: X. Lucas Lu, Ph.D. Department of Mechanical Engineering, University of Delaware, 130 Academy Street, Newark, DE 19716, Telephone: (302) 831-3581,
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17
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Moo EK, Herzog W. Unfolding of membrane ruffles of in situ chondrocytes under compressive loads. J Orthop Res 2017; 35:304-310. [PMID: 27064602 DOI: 10.1002/jor.23260] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/31/2016] [Indexed: 02/04/2023]
Abstract
Impact loading results in chondrocyte death. Previous studies implicated high tensile strain rates in chondrocyte membranes as the cause of impact-induced cell deaths. However, this hypothesis relies on the untested assumption that chondrocyte membranes unfold in vivo during physiological tissue compression, but do not unfold during impact loading. Although membrane unfolding has been observed in isolated chondrocytes during osmotically induced swelling and mechanical compression, it is not known if membrane unfolding also occurs in chondrocytes embedded in their natural extracellular matrix. This study was aimed at quantifying changes in membrane morphology of in situ superficial zone chondrocytes during slow physiological cartilage compression. Bovine cartilage-bone explants were loaded at 5 μm/s to nominal compressive strains ranging from 0% to 50%. After holding the final strains for 45 min, the loaded cartilage was chemically pre-fixed for 12 h. The cartilage layer was post-processed for visualization of cell ultrastructure using electron microscopy. The changes in membrane morphology in superficial zone cells were quantified from planar electron micrographs by measuring the roughness and the complexity of the cell surfaces. Qualitatively, the cell surface ruffles that existed before loading disappeared when cartilage was loaded. Quantitatively, the roughness and complexity of cell surfaces decreased with increasing load magnitudes, suggesting a load-dependent use of membrane reservoirs. Chondrocyte membranes unfold in a load-dependent manner when cartilage is compressed. Under physiologically meaningful loading conditions, the cells likely expand their surface through unfolding of the membrane ruffles, and therefore avoid direct stretch of the cell membrane. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:304-310, 2017.
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Affiliation(s)
- Eng Kuan Moo
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, 2500 University Drive N.W., Calgary, Alberta, T2N 1N4, Canada
| | - Walter Herzog
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, 2500 University Drive N.W., Calgary, Alberta, T2N 1N4, Canada
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18
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Servin-Vences MR, Moroni M, Lewin GR, Poole K. Direct measurement of TRPV4 and PIEZO1 activity reveals multiple mechanotransduction pathways in chondrocytes. eLife 2017; 6. [PMID: 28135189 PMCID: PMC5279942 DOI: 10.7554/elife.21074] [Citation(s) in RCA: 151] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 01/03/2017] [Indexed: 12/24/2022] Open
Abstract
The joints of mammals are lined with cartilage, comprised of individual chondrocytes embedded in a specialized extracellular matrix. Chondrocytes experience a complex mechanical environment and respond to changing mechanical loads in order to maintain cartilage homeostasis. It has been proposed that mechanically gated ion channels are of functional importance in chondrocyte mechanotransduction; however, direct evidence of mechanical current activation in these cells has been lacking. We have used high-speed pressure clamp and elastomeric pillar arrays to apply distinct mechanical stimuli to primary murine chondrocytes, stretch of the membrane and deflection of cell-substrate contacts points, respectively. Both TRPV4 and PIEZO1 channels contribute to currents activated by stimuli applied at cell-substrate contacts but only PIEZO1 mediates stretch-activated currents. These data demonstrate that there are separate, but overlapping, mechanoelectrical transduction pathways in chondrocytes.
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Affiliation(s)
| | - Mirko Moroni
- Department of Neuroscience, Max Delbruck Center for Molecular Medicine, Berlin, Germany
| | - Gary R Lewin
- Department of Neuroscience, Max Delbruck Center for Molecular Medicine, Berlin, Germany
| | - Kate Poole
- Department of Neuroscience, Max Delbruck Center for Molecular Medicine, Berlin, Germany.,Department of Physiology, School of Medical Sciences, University of New South Wales, Sydney, Australia.,EMBL Australia node for Single Molecule Sciences, School of Medical Sciences, University of New South Wales, Sydney, Australia
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19
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Early in situ changes in chondrocyte biomechanical responses due to a partial meniscectomy in the lateral compartment of the mature rabbit knee joint. J Biomech 2016; 49:4057-4064. [PMID: 27825604 DOI: 10.1016/j.jbiomech.2016.10.039] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 10/14/2016] [Accepted: 10/25/2016] [Indexed: 11/21/2022]
Abstract
We determined the biomechanical responses of chondrocytes to indentation at specific locations within the superficial zone of cartilage (i.e. patellar, femoral groove, femoral condylar and tibial plateau sites) taken from female New Zealand white rabbits three days after a partial meniscectomy in the lateral compartment of a knee joint. Confocal laser scanning microscopy combined with a custom indentation system was utilized to image chondrocyte responses at sites taken from ten contralateral and experimental knee joints. Cell volume, height, width and depth changes, global, local axial and transverse strains and Young׳s moduli were determined. Histological assessment was performed and proteoglycan content from the superficial zone of each site was determined. Relative to contralateral group cells, patellar, femoral groove and lateral femoral condyle cells in the experimental group underwent greater volume decreases (p < 0.05), due to smaller lateral expansions (with greater decreases in cell height only for the lateral femoral condyle cells; p < 0.05) whereas medial femoral and medial tibial plateau cells underwent smaller volume decreases (p < 0.05), due to less deformation in cell height (p < 0.05). Proteoglycan content was reduced in the patellar (p > 0.05), femoral groove, medial femoral condyle and medial tibial plateau experimental sites (p < 0.05). The findings suggest: (i) cell biomechanical responses to cartilage loading in the rabbit knee joint can become altered as early as 3 days after a partial meniscectomy, (ii) are site-specific, and (iii) occur before alterations in tissue mechanics or changes detectable with histology.
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20
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Chan DD, Cai L, Butz KD, Trippel SB, Nauman EA, Neu CP. In vivo articular cartilage deformation: noninvasive quantification of intratissue strain during joint contact in the human knee. Sci Rep 2016; 6:19220. [PMID: 26752228 PMCID: PMC4707486 DOI: 10.1038/srep19220] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 12/08/2015] [Indexed: 12/25/2022] Open
Abstract
The in vivo measurement of articular cartilage deformation is essential to understand how mechanical forces distribute throughout the healthy tissue and change over time in the pathologic joint. Displacements or strain may serve as a functional imaging biomarker for healthy, diseased, and repaired tissues, but unfortunately intratissue cartilage deformation in vivo is largely unknown. Here, we directly quantified for the first time deformation patterns through the thickness of tibiofemoral articular cartilage in healthy human volunteers. Magnetic resonance imaging acquisitions were synchronized with physiologically relevant compressive loading and used to visualize and measure regional displacement and strain of tibiofemoral articular cartilage in a sagittal plane. We found that compression (of 1/2 body weight) applied at the foot produced a sliding, rigid-body displacement at the tibiofemoral cartilage interface, that loading generated subject- and gender-specific and regionally complex patterns of intratissue strains, and that dominant cartilage strains (approaching 12%) were in shear. Maximum principle and shear strain measures in the tibia were correlated with body mass index. Our MRI-based approach may accelerate the development of regenerative therapies for diseased or damaged cartilage, which is currently limited by the lack of reliable in vivo methods for noninvasive assessment of functional changes following treatment.
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Affiliation(s)
- Deva D Chan
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907
| | - Luyao Cai
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907
| | - Kent D Butz
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, 47907
| | - Stephen B Trippel
- Departments of Orthopaedic Surgery and Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, 46202
| | - Eric A Nauman
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907.,School of Mechanical Engineering, Purdue University, West Lafayette, IN, 47907
| | - Corey P Neu
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, 47907.,Department of Mechanical Engineering, University of Colorado, Boulder, CO, 80309
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21
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Fick JM, Ronkainen A, Herzog W, Korhonen RK. Site-dependent biomechanical responses of chondrocytes in the rabbit knee joint. J Biomech 2015; 48:4010-4019. [PMID: 26601568 DOI: 10.1016/j.jbiomech.2015.09.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 09/09/2015] [Accepted: 09/26/2015] [Indexed: 11/15/2022]
Abstract
Biomechanical responses of chondrocytes were determined in specific locations within the superficial zone of patellar, femoral groove, femoral condyle and tibial plateau cartilages obtained from female New Zealand White rabbits. A confocal laser scanning microscope combined with a custom indentation system was utilized for experimentation. Changes in cell volumes and dimensions (i.e. cell height, width and depth) due to loading, global, local axial and transverse strains were determined for each site. Tissue composition and structure was analysed at each indentation site with digital densitometry, polarized light microscopy and Fourier transform infrared imaging spectroscopy. Patellar cells underwent greater volume decreases (compared to femoral groove cells; p<0.05) primarily due to greater decreases in cell height (p<0.05), consistent with greater levels of both global and local axial strains (p<0.05). Lateral condyle cells underwent greater volume decreases (compared to lateral plateau cells; p<0.05) primarily due to greater decreases in cell height, consistent with greater levels of tissue strains (p<0.05). Medial condyle cells underwent smaller volume decreases (compared to medial plateau cells; p<0.05) primarily due to elevated cell expansions in the depth direction, which was consistent with greater levels of minor transverse strains (p<0.05). Site-dependent differences in collagen orientation angles agreed conceptually with the observed cell dimensional changes. Chondrocyte biomechanical responses were highly site-dependent and corresponded primarily with the orientation of the collagen fibrils. The observed differences were thought to be due to the different biomechanical loading conditions at each site.
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Affiliation(s)
- J M Fick
- Department of Applied Physics, University of Eastern Finland, Yliopistonranta 1, Kuopio FI-70211, Finland.
| | - A Ronkainen
- Department of Applied Physics, University of Eastern Finland, Yliopistonranta 1, Kuopio FI-70211, Finland
| | - W Herzog
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - R K Korhonen
- Department of Applied Physics, University of Eastern Finland, Yliopistonranta 1, Kuopio FI-70211, Finland
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22
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Gao J, Roan E, Williams JL. Regional variations in growth plate chondrocyte deformation as predicted by three-dimensional multi-scale simulations. PLoS One 2015; 10:e0124862. [PMID: 25885547 PMCID: PMC4401775 DOI: 10.1371/journal.pone.0124862] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 03/10/2015] [Indexed: 11/17/2022] Open
Abstract
The physis, or growth plate, is a complex disc-shaped cartilage structure that is responsible for longitudinal bone growth. In this study, a multi-scale computational approach was undertaken to better understand how physiological loads are experienced by chondrocytes embedded inside chondrons when subjected to moderate strain under instantaneous compressive loading of the growth plate. Models of representative samples of compressed bone/growth-plate/bone from a 0.67 mm thick 4-month old bovine proximal tibial physis were subjected to a prescribed displacement equal to 20% of the growth plate thickness. At the macroscale level, the applied compressive deformation resulted in an overall compressive strain across the proliferative-hypertrophic zone of 17%. The microscale model predicted that chondrocytes sustained compressive height strains of 12% and 6% in the proliferative and hypertrophic zones, respectively, in the interior regions of the plate. This pattern was reversed within the outer 300 μm region at the free surface where cells were compressed by 10% in the proliferative and 26% in the hypertrophic zones, in agreement with experimental observations. This work provides a new approach to study growth plate behavior under compression and illustrates the need for combining computational and experimental methods to better understand the chondrocyte mechanics in the growth plate cartilage. While the current model is relevant to fast dynamic events, such as heel strike in walking, we believe this approach provides new insight into the mechanical factors that regulate bone growth at the cell level and provides a basis for developing models to help interpret experimental results at varying time scales.
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Affiliation(s)
- Jie Gao
- Departments of Mechanical Engineering, University of Memphis Memphis, Tennessee, 38152, United States of America
| | - Esra Roan
- Department of Biomedical Engineering, University of Memphis Memphis, Tennessee, 38152, United States of America
| | - John L Williams
- Department of Biomedical Engineering, University of Memphis Memphis, Tennessee, 38152, United States of America
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23
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Bleuel J, Zaucke F, Brüggemann GP, Niehoff A. Effects of cyclic tensile strain on chondrocyte metabolism: a systematic review. PLoS One 2015; 10:e0119816. [PMID: 25822615 PMCID: PMC4379081 DOI: 10.1371/journal.pone.0119816] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 01/16/2015] [Indexed: 12/25/2022] Open
Abstract
Chondrocytes reorganize the extracellular matrix of articular cartilage in response to externally applied loads. Thereby, different loading characteristics lead to different biological responses. Despite of active research in this area, it is still unclear which parts of the extracellular matrix adapt in what ways, and how specific loading characteristics affect matrix changes. This review focuses on the influence of cyclic tensile strain on chondrocyte metabolism in vitro. It also aimed to identify anabolic or catabolic chondrocyte responses to different loading protocols. The key findings show that loading cells up to 3% strain, 0.17 Hz, and 2 h, resulted in weak or no biological responses. Loading between 3–10% strain, 0.17–0.5 Hz, and 2–12 h led to anabolic responses; and above 10% strain, 0.5 Hz, and 12 h catabolic events predominated. However, this review also discusses that various other factors are involved in the remodeling of the extracellular matrix in response to loading, and that parameters like an inflammatory environment might influence the biological response.
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Affiliation(s)
- Judith Bleuel
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, Köln, Germany
- * E-mail:
| | - Frank Zaucke
- Center for Biochemistry, Medical Faculty, University of Cologne, Köln, Germany
- Cologne Center for Musculoskeletal Biomechanics, Medical Faculty, University of Cologne, Köln, Germany
| | - Gert-Peter Brüggemann
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, Köln, Germany
- Cologne Center for Musculoskeletal Biomechanics, Medical Faculty, University of Cologne, Köln, Germany
| | - Anja Niehoff
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, Köln, Germany
- Cologne Center for Musculoskeletal Biomechanics, Medical Faculty, University of Cologne, Köln, Germany
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24
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Tanska P, Mononen ME, Korhonen RK. A multi-scale finite element model for investigation of chondrocyte mechanics in normal and medial meniscectomy human knee joint during walking. J Biomech 2015; 48:1397-406. [PMID: 25795269 DOI: 10.1016/j.jbiomech.2015.02.043] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 02/17/2015] [Indexed: 10/23/2022]
Abstract
Mechanical signals experienced by chondrocytes (articular cartilage cells) modulate cell synthesis and cartilage health. Multi-scale modeling can be used to study how forces are transferred from joint surfaces through tissues to chondrocytes. Therefore, estimation of chondrocyte behavior during certain physical activities, such as walking, could provide information about how cells respond to normal and abnormal loading in joints. In this study, a 3D multi-scale model was developed for evaluating chondrocyte and surrounding peri- and extracellular matrix responses during gait loading within healthy and medial meniscectomy knee joints. The knee joint geometry was based on MRI, whereas the input used for gait loading was obtained from the literature. Femoral and tibial cartilages were modeled as fibril-reinforced poroviscoelastic materials, whereas menisci were considered as transversely isotropic. Fluid pressures in the chondrocyte and cartilage tissue increased up to 2MPa (an increase of 30%) in the meniscectomy joint compared to the normal, healthy joint. The elevated level of fluid pressure was observed during the entire stance phase of gait. A medial meniscectomy caused substantially larger (up to 60%) changes in maximum principal strains in the chondrocyte compared to those in the peri- or extracellular matrices. Chondrocyte volume or morphology did not change substantially due to a medial meniscectomy. Current findings suggest that during walking chondrocyte deformations are not substantially altered due to a medial meniscectomy, while abnormal joint loading exposes chondrocytes to elevated levels of fluid pressure and maximum principal strains (compared to strains in the peri- or extracellular matrices). These might contribute to cell viability and the onset of osteoarthritis.
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Affiliation(s)
- Petri Tanska
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland; Diagnostic Imaging Centre, Kuopio University Hospital, Kuopio, Finland.
| | - Mika E Mononen
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - Rami K Korhonen
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland; Diagnostic Imaging Centre, Kuopio University Hospital, Kuopio, Finland
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25
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Fick JM, Huttu MRJ, Lammi MJ, Korhonen RK. In vitro glycation of articular cartilage alters the biomechanical response of chondrocytes in a depth-dependent manner. Osteoarthritis Cartilage 2014; 22:1410-8. [PMID: 25278052 DOI: 10.1016/j.joca.2014.07.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 07/16/2014] [Accepted: 07/18/2014] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine if increasing cartilage cross-links through in vitro glycation of cartilage explants can alter the biomechanical response of chondrocytes to compressive deformation. METHOD Bovine osteochondral explants were either incubated with cell culture solution supplemented with (n = 7) or without (n = 7) ribose for 42 h in order to induce glycation. Deformation-induced changes in cell volume, dimensions and local tissue strains were determined through confocal laser scanning microscopy (CLSM) and the use of a custom built micro-compression device. Osteochondral explants were also utilized to demonstrate changes in depth-wise tissue properties, biomechanical tissue properties and cross-links such as pentosidine (Pent), hydroxylysyl pyridinoline (HP) and lysyl pyridinoline (LP). RESULTS The ribose treated osteochondral samples experienced reduced cell volume deformation in the upper tissue zone by ∼ 8% (P = 0.005), as compared the control samples, through restricting cell expansion. In the deeper tissue zone, cell volume deformation was increased by ∼ 12% (P < 0.001) via the transmission of mechanical signals further into the tissue depth. Biomechanical testing of the ribose treated osteochondral samples demonstrated an increase in the equilibrium and dynamic strain dependent moduli (P < 0.001 and P = 0.008, respectively). The biochemical analysis revealed an increase in Pent cross-links (P < 0.001). Depth-wise tissue property analyses revealed increased levels of carbohydrate content, greater levels of fixed charge density and an increased carbohydrate to protein ratio from 6 to 16%, 55-100% and 72-79% of the normalized tissue thickness (from the surface), respectively, in the ribose-treated group (P < 0.05). CONCLUSION In vitro glycation alters the biomechanical response of chondrocytes in cartilage differently in upper and deeper zones, offering possible insights into how aging could alter cell deformation behavior in cartilage.
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Affiliation(s)
- J M Fick
- Department of Applied Physics, University of Eastern Finland, Kuopio FI-70211, Finland.
| | - M R J Huttu
- Department of Applied Physics, University of Eastern Finland, Kuopio FI-70211, Finland
| | - M J Lammi
- Department of Applied Physics, University of Eastern Finland, Kuopio FI-70211, Finland
| | - R K Korhonen
- Department of Applied Physics, University of Eastern Finland, Kuopio FI-70211, Finland
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26
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Snedeker JG. The nuclear envelope as a mechanostat: a central cog in the machinery of cell and tissue regulation? BONEKEY REPORTS 2014; 3:562. [PMID: 25177488 DOI: 10.1038/bonekey.2014.57] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jess G Snedeker
- Department of Orthopaedics, Balgrist Hospital, University of Zurich , Zurich, Switzerland ; Institute for Biomechanics, Swiss Federal Institute of Technology , Zurich, Switzerland
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27
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Madden RMJ, Han SK, Herzog W. The effect of compressive loading magnitude on in situ chondrocyte calcium signaling. Biomech Model Mechanobiol 2014; 14:135-42. [PMID: 24853775 PMCID: PMC4282695 DOI: 10.1007/s10237-014-0594-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 05/06/2014] [Indexed: 12/19/2022]
Abstract
Chondrocyte metabolism is stimulated by deformation and is associated with structural changes in the cartilage extracellular matrix (ECM), suggesting that these cells are involved in maintaining tissue health and integrity. Calcium signaling is an initial step in chondrocyte mechanotransduction that has been linked to many cellular processes. Previous studies using isolated chondrocytes proposed loading magnitude as an important factor regulating this response. However, calcium signaling in the intact cartilage differs compared to isolated cells. The purpose of this study was to investigate the effect of loading magnitude on chondrocyte calcium signaling in intact cartilage. We hypothesized that the percentage of cells exhibiting at least one calcium signal increases with increasing load. Fully intact rabbit femoral condyle and patellar bone/cartilage samples were incubated in calcium-sensitive dyes and imaged continuously under compressive loads of 10-40 % strain. Calcium signaling was primarily associated with the dynamic loading phase and greatly increased beyond a threshold deformation of about 10 % nominal tissue strain. There was a trend toward more cells exhibiting calcium signaling as loading magnitude increased (p = 0.133). These results provide novel information toward identifying mechanisms underlying calcium-dependent signaling pathways related to cartilage homeostasis and possibly the onset and progression of osteoarthritis.
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Affiliation(s)
- Ryan M J Madden
- Human Performance Laboratory, University of Calgary, 2500 University Dr. NW, Calgary, AB, T2N 1N4, Canada,
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28
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Extracellular matrix integrity affects the mechanical behaviour of in-situ chondrocytes under compression. J Biomech 2014; 47:1004-13. [PMID: 24480705 DOI: 10.1016/j.jbiomech.2014.01.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 12/31/2013] [Accepted: 01/03/2014] [Indexed: 11/22/2022]
Abstract
Cartilage lesions change the microenvironment of cells and may accelerate cartilage degradation through catabolic responses from chondrocytes. In this study, we investigated the effects of structural integrity of the extracellular matrix (ECM) on chondrocytes by comparing the mechanics of cells surrounded by an intact ECM with cells close to a cartilage lesion using experimental and numerical methods. Experimentally, 15% nominal compression was applied to bovine cartilage tissues using a light-transmissible compression system. Target cells in the intact ECM and near lesions were imaged by dual-photon microscopy. Changes in cell morphology (N(cell)=32 for both ECM conditions) were quantified. A two-scale (tissue level and cell level) Finite Element (FE) model was also developed. A 15% nominal compression was applied to a non-linear, biphasic tissue model with the corresponding cell level models studied at different radial locations from the centre of the sample in the transient phase and at steady state. We studied the Green-Lagrange strains in the tissue and cells. Experimental and theoretical results indicated that cells near lesions deform less axially than chondrocytes in the intact ECM at steady state. However, cells near lesions experienced large tensile strains in the principal height direction, which are likely associated with non-uniform tissue radial bulging. Previous experiments showed that tensile strains of high magnitude cause an up-regulation of digestive enzyme gene expressions. Therefore, we propose that cartilage degradation near tissue lesions may be due to the large tensile strains in the principal height direction applied to cells, thus leading to an up-regulation of catabolic factors.
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