1
|
Manning L. Responsible innovation: Mitigating the food safety aspects of cultured meat production. J Food Sci 2024; 89:4638-4659. [PMID: 38980973 DOI: 10.1111/1750-3841.17228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 05/30/2024] [Accepted: 06/17/2024] [Indexed: 07/11/2024]
Abstract
There is much interest in cultured (cultivated) meat as a potential solution to concerns over the ecological and environmental footprint of food production, especially from animal-derived food products. The aim of this critical review is to undertake a structured analysis of existing literature to (i) identify the range of materials that could be used within the cultured meat process; (ii) explore the potential biological and chemical food safety issues that arise; (iii) identify the known and also novel aspects of the food safety hazard portfolio that will inform hazard analysis and risk assessment approaches, and (iv) position a responsible innovation framework that can be utilized to mitigate food safety concerns with specific emphasis on cultured meat. Although a number of potential food safety hazards are identified that need to be considered within a food safety plan, further research is required to validate and verify that these food safety hazards have been suitably controlled and, where possible, eliminated. The responsible innovation framework developed herein, which extends beyond hazard analysis and traditional risk assessment approaches, can be applied in multiple contexts, including this use case of cultured meat production.
Collapse
Affiliation(s)
- Louise Manning
- Lincoln Institute for Agri-Food Technology, University of Lincoln, Lincoln, UK
| |
Collapse
|
2
|
Snow F, O'Connell C, Yang P, Kita M, Pirogova E, Williams RJ, Kapsa RMI, Quigley A. Engineering interfacial tissues: The myotendinous junction. APL Bioeng 2024; 8:021505. [PMID: 38841690 PMCID: PMC11151436 DOI: 10.1063/5.0189221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 05/06/2024] [Indexed: 06/07/2024] Open
Abstract
The myotendinous junction (MTJ) is the interface connecting skeletal muscle and tendon tissues. This specialized region represents the bridge that facilitates the transmission of contractile forces from muscle to tendon, and ultimately the skeletal system for the creation of movement. MTJs are, therefore, subject to high stress concentrations, rendering them susceptible to severe, life-altering injuries. Despite the scarcity of knowledge obtained from MTJ formation during embryogenesis, several attempts have been made to engineer this complex interfacial tissue. These attempts, however, fail to achieve the level of maturity and mechanical complexity required for in vivo transplantation. This review summarizes the strategies taken to engineer the MTJ, with an emphasis on how transitioning from static to mechanically inducive dynamic cultures may assist in achieving myotendinous maturity.
Collapse
|
3
|
Hidalgo-Alvarez V, Madl CM. Leveraging Biomaterial Platforms to Study Aging-Related Neural and Muscular Degeneration. Biomolecules 2024; 14:69. [PMID: 38254669 PMCID: PMC10813704 DOI: 10.3390/biom14010069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 12/28/2023] [Accepted: 12/30/2023] [Indexed: 01/24/2024] Open
Abstract
Aging is a complex multifactorial process that results in tissue function impairment across the whole organism. One of the common consequences of this process is the loss of muscle mass and the associated decline in muscle function, known as sarcopenia. Aging also presents with an increased risk of developing other pathological conditions such as neurodegeneration. Muscular and neuronal degeneration cause mobility issues and cognitive impairment, hence having a major impact on the quality of life of the older population. The development of novel therapies that can ameliorate the effects of aging is currently hindered by our limited knowledge of the underlying mechanisms and the use of models that fail to recapitulate the structure and composition of the cell microenvironment. The emergence of bioengineering techniques based on the use of biomimetic materials and biofabrication methods has opened the possibility of generating 3D models of muscular and nervous tissues that better mimic the native extracellular matrix. These platforms are particularly advantageous for drug testing and mechanistic studies. In this review, we discuss the developments made in the creation of 3D models of aging-related neuronal and muscular degeneration and we provide a perspective on the future directions for the field.
Collapse
Affiliation(s)
| | - Christopher M. Madl
- Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA;
| |
Collapse
|
4
|
Carraro E, Rossi L, Maghin E, Canton M, Piccoli M. 3D in vitro Models of Pathological Skeletal Muscle: Which Cells and Scaffolds to Elect? Front Bioeng Biotechnol 2022; 10:941623. [PMID: 35898644 PMCID: PMC9313593 DOI: 10.3389/fbioe.2022.941623] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 06/21/2022] [Indexed: 12/29/2022] Open
Abstract
Skeletal muscle is a fundamental tissue of the human body with great plasticity and adaptation to diseases and injuries. Recreating this tissue in vitro helps not only to deepen its functionality, but also to simulate pathophysiological processes. In this review we discuss the generation of human skeletal muscle three-dimensional (3D) models obtained through tissue engineering approaches. First, we present an overview of the most severe myopathies and the two key players involved: the variety of cells composing skeletal muscle tissue and the different components of its extracellular matrix. Then, we discuss the peculiar characteristics among diverse in vitro models with a specific focus on cell sources, scaffold composition and formulations, and fabrication techniques. To conclude, we highlight the efficacy of 3D models in mimicking patient-specific myopathies, deepening muscle disease mechanisms or investigating possible therapeutic effects.
Collapse
Affiliation(s)
- Eugenia Carraro
- Istituto di Ricerca Pediatrica Città della Speranza, Padova, Italy
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Lucia Rossi
- Istituto di Ricerca Pediatrica Città della Speranza, Padova, Italy
| | - Edoardo Maghin
- Istituto di Ricerca Pediatrica Città della Speranza, Padova, Italy
| | - Marcella Canton
- Istituto di Ricerca Pediatrica Città della Speranza, Padova, Italy
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Martina Piccoli
- Istituto di Ricerca Pediatrica Città della Speranza, Padova, Italy
- *Correspondence: Martina Piccoli,
| |
Collapse
|
5
|
Customized bioreactor enables the production of 3D diaphragmatic constructs influencing matrix remodeling and fibroblast overgrowth. NPJ Regen Med 2022; 7:25. [PMID: 35468920 PMCID: PMC9038738 DOI: 10.1038/s41536-022-00222-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 03/01/2022] [Indexed: 02/06/2023] Open
Abstract
The production of skeletal muscle constructs useful for replacing large defects in vivo, such as in congenital diaphragmatic hernia (CDH), is still considered a challenge. The standard application of prosthetic material presents major limitations, such as hernia recurrences in a remarkable number of CDH patients. With this work, we developed a tissue engineering approach based on decellularized diaphragmatic muscle and human cells for the in vitro generation of diaphragmatic-like tissues as a proof-of-concept of a new option for the surgical treatment of large diaphragm defects. A customized bioreactor for diaphragmatic muscle was designed to control mechanical stimulation and promote radial stretching during the construct engineering. In vitro tests demonstrated that both ECM remodeling and fibroblast overgrowth were positively influenced by the bioreactor culture. Mechanically stimulated constructs also increased tissue maturation, with the formation of new oriented and aligned muscle fibers. Moreover, after in vivo orthotopic implantation in a surgical CDH mouse model, mechanically stimulated muscles maintained the presence of human cells within myofibers and hernia recurrence did not occur, suggesting the value of this approach for treating diaphragm defects.
Collapse
|
6
|
Bramson MTK, Van Houten SK, Corr DT. Mechanobiology in Tendon, Ligament, and Skeletal Muscle Tissue Engineering. J Biomech Eng 2021; 143:070801. [PMID: 33537704 DOI: 10.1115/1.4050035] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Indexed: 12/28/2022]
Abstract
Tendon, ligament, and skeletal muscle are highly organized tissues that largely rely on a hierarchical collagenous matrix to withstand high tensile loads experienced in activities of daily life. This critical biomechanical role predisposes these tissues to injury, and current treatments fail to recapitulate the biomechanical function of native tissue. This has prompted researchers to pursue engineering functional tissue replacements, or dysfunction/disease/development models, by emulating in vivo stimuli within in vitro tissue engineering platforms-specifically mechanical stimulation, as well as active contraction in skeletal muscle. Mechanical loading is critical for matrix production and organization in the development, maturation, and maintenance of native tendon, ligament, and skeletal muscle, as well as their interfaces. Tissue engineers seek to harness these mechanobiological benefits using bioreactors to apply both static and dynamic mechanical stimulation to tissue constructs, and induce active contraction in engineered skeletal muscle. The vast majority of engineering approaches in these tissues are scaffold-based, providing interim structure and support to engineered constructs, and sufficient integrity to withstand mechanical loading. Alternatively, some recent studies have employed developmentally inspired scaffold-free techniques, relying on cellular self-assembly and matrix production to form tissue constructs. Whether utilizing a scaffold or not, incorporation of mechanobiological stimuli has been shown to improve the composition, structure, and biomechanical function of engineered tendon, ligament, and skeletal muscle. Together, these findings highlight the importance of mechanobiology and suggest how it can be leveraged to engineer these tissues and their interfaces, and to create functional multitissue constructs.
Collapse
Affiliation(s)
- Michael T K Bramson
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180
| | - Sarah K Van Houten
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180
| | - David T Corr
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180
| |
Collapse
|
7
|
Alarcin E, Bal-Öztürk A, Avci H, Ghorbanpoor H, Dogan Guzel F, Akpek A, Yesiltas G, Canak-Ipek T, Avci-Adali M. Current Strategies for the Regeneration of Skeletal Muscle Tissue. Int J Mol Sci 2021; 22:5929. [PMID: 34072959 PMCID: PMC8198586 DOI: 10.3390/ijms22115929] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/21/2021] [Accepted: 05/26/2021] [Indexed: 12/11/2022] Open
Abstract
Traumatic injuries, tumor resections, and degenerative diseases can damage skeletal muscle and lead to functional impairment and severe disability. Skeletal muscle regeneration is a complex process that depends on various cell types, signaling molecules, architectural cues, and physicochemical properties to be successful. To promote muscle repair and regeneration, various strategies for skeletal muscle tissue engineering have been developed in the last decades. However, there is still a high demand for the development of new methods and materials that promote skeletal muscle repair and functional regeneration to bring approaches closer to therapies in the clinic that structurally and functionally repair muscle. The combination of stem cells, biomaterials, and biomolecules is used to induce skeletal muscle regeneration. In this review, we provide an overview of different cell types used to treat skeletal muscle injury, highlight current strategies in biomaterial-based approaches, the importance of topography for the successful creation of functional striated muscle fibers, and discuss novel methods for muscle regeneration and challenges for their future clinical implementation.
Collapse
Affiliation(s)
- Emine Alarcin
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Marmara University, 34854 Istanbul, Turkey;
| | - Ayca Bal-Öztürk
- Department of Analytical Chemistry, Faculty of Pharmacy, Istinye University, 34010 Istanbul, Turkey;
- Department of Stem Cell and Tissue Engineering, Institute of Health Sciences, Istinye University, 34010 Istanbul, Turkey
| | - Hüseyin Avci
- Department of Metallurgical and Materials Engineering, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey;
- Cellular Therapy and Stem Cell Research Center, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey
- AvciBio Research Group, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey;
- Translational Medicine Research and Clinical Center, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey
| | - Hamed Ghorbanpoor
- AvciBio Research Group, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey;
- Department of Biomedical Engineering, Ankara Yildirim Beyazit University, 06010 Ankara, Turkey;
- Department of Biomedical Engineering, Eskisehir Osmangazi University, 26040 Eskisehir, Turkey
| | - Fatma Dogan Guzel
- Department of Biomedical Engineering, Ankara Yildirim Beyazit University, 06010 Ankara, Turkey;
| | - Ali Akpek
- Department of Bioengineering, Gebze Technical University, 41400 Gebze, Turkey; (A.A.); (G.Y.)
| | - Gözde Yesiltas
- Department of Bioengineering, Gebze Technical University, 41400 Gebze, Turkey; (A.A.); (G.Y.)
| | - Tuba Canak-Ipek
- Department of Thoracic and Cardiovascular Surgery, University Hospital Tuebingen, Calwerstraße 7/1, 72076 Tuebingen, Germany;
| | - Meltem Avci-Adali
- Department of Thoracic and Cardiovascular Surgery, University Hospital Tuebingen, Calwerstraße 7/1, 72076 Tuebingen, Germany;
| |
Collapse
|
8
|
Aguilar-Agon KW, Capel AJ, Martin NRW, Player DJ, Lewis MP. Mechanical loading stimulates hypertrophy in tissue-engineered skeletal muscle: Molecular and phenotypic responses. J Cell Physiol 2019; 234:23547-23558. [PMID: 31180593 PMCID: PMC6771594 DOI: 10.1002/jcp.28923] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/17/2019] [Accepted: 05/20/2019] [Indexed: 12/17/2022]
Abstract
Mechanical loading of skeletal muscle results in molecular and phenotypic adaptations typified by enhanced muscle size. Studies on humans are limited by the need for repeated sampling, and studies on animals have methodological and ethical limitations. In this investigation, three‐dimensional skeletal muscle was tissue‐engineered utilizing the murine cell line C2C12, which bears resemblance to native tissue and benefits from the advantages of conventional in vitro experiments. The work aimed to determine if mechanical loading induced an anabolic hypertrophic response, akin to that described in vivo after mechanical loading in the form of resistance exercise. Specifically, we temporally investigated candidate gene expression and Akt‐mechanistic target of rapamycin 1 signalling along with myotube growth and tissue function. Mechanical loading (construct length increase of 15%) significantly increased insulin‐like growth factor‐1 and MMP‐2 messenger RNA expression 21 hr after overload, and the levels of the atrophic gene MAFbx were significantly downregulated 45 hr after mechanical overload. In addition, p70S6 kinase and 4EBP‐1 phosphorylation were upregulated immediately after mechanical overload. Maximal contractile force was augmented 45 hr after load with a 265% increase in force, alongside significant hypertrophy of the myotubes within the engineered muscle. Overall, mechanical loading of tissue‐engineered skeletal muscle induced hypertrophy and improved force production.
Collapse
Affiliation(s)
- Kathryn W Aguilar-Agon
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom
| | - Andrew J Capel
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom
| | - Neil R W Martin
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom
| | - Darren J Player
- Division of Surgery, University College London, London, United Kingdom
| | - Mark P Lewis
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom
| |
Collapse
|
9
|
Maleiner B, Tomasch J, Heher P, Spadiut O, Rünzler D, Fuchs C. The Importance of Biophysical and Biochemical Stimuli in Dynamic Skeletal Muscle Models. Front Physiol 2018; 9:1130. [PMID: 30246791 PMCID: PMC6113794 DOI: 10.3389/fphys.2018.01130] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 07/30/2018] [Indexed: 12/31/2022] Open
Abstract
Classical approaches to engineer skeletal muscle tissue based on current regenerative and surgical procedures still do not meet the desired outcome for patient applications. Besides the evident need to create functional skeletal muscle tissue for the repair of volumetric muscle defects, there is also growing demand for platforms to study muscle-related diseases, such as muscular dystrophies or sarcopenia. Currently, numerous studies exist that have employed a variety of biomaterials, cell types and strategies for maturation of skeletal muscle tissue in 2D and 3D environments. However, researchers are just at the beginning of understanding the impact of different culture settings and their biochemical (growth factors and chemical changes) and biophysical cues (mechanical properties) on myogenesis. With this review we intend to emphasize the need for new in vitro skeletal muscle (disease) models to better recapitulate important structural and functional aspects of muscle development. We highlight the importance of choosing appropriate system components, e.g., cell and biomaterial type, structural and mechanical matrix properties or culture format, and how understanding their interplay will enable researchers to create optimized platforms to investigate myogenesis in healthy and diseased tissue. Thus, we aim to deliver guidelines for experimental designs to allow estimation of the potential influence of the selected skeletal muscle tissue engineering setup on the myogenic outcome prior to their implementation. Moreover, we offer a workflow to facilitate identifying and selecting different analytical tools to demonstrate the successful creation of functional skeletal muscle tissue. Ultimately, a refinement of existing strategies will lead to further progression in understanding important aspects of muscle diseases, muscle aging and muscle regeneration to improve quality of life of patients and enable the establishment of new treatment options.
Collapse
Affiliation(s)
- Babette Maleiner
- Department of Biochemical Engineering, University of Applied Sciences Technikum Wien, Vienna, Austria.,The Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Janine Tomasch
- Department of Biochemical Engineering, University of Applied Sciences Technikum Wien, Vienna, Austria.,The Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Philipp Heher
- The Austrian Cluster for Tissue Regeneration, Vienna, Austria.,Ludwig Boltzmann Institute for Experimental and Clinical Traumatology/AUVA Research Center, Vienna, Austria.,Trauma Care Consult GmbH, Vienna, Austria
| | - Oliver Spadiut
- Institute of Chemical Engineering, Vienna University of Technology, Vienna, Austria
| | - Dominik Rünzler
- Department of Biochemical Engineering, University of Applied Sciences Technikum Wien, Vienna, Austria.,The Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Christiane Fuchs
- Department of Biochemical Engineering, University of Applied Sciences Technikum Wien, Vienna, Austria.,The Austrian Cluster for Tissue Regeneration, Vienna, Austria
| |
Collapse
|
10
|
Kasper AM, Turner DC, Martin NRW, Sharples AP. Mimicking exercise in three-dimensional bioengineered skeletal muscle to investigate cellular and molecular mechanisms of physiological adaptation. J Cell Physiol 2017; 233:1985-1998. [DOI: 10.1002/jcp.25840] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 02/02/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Andreas M. Kasper
- Stem Cells, Ageing, and Molecular Physiology (SCAMP) Unit, Exercise Metabolism and Adaptation Research group, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences; Liverpool John Moores University; Liverpool UK
| | - Daniel C. Turner
- Stem Cells, Ageing, and Molecular Physiology (SCAMP) Unit, Exercise Metabolism and Adaptation Research group, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences; Liverpool John Moores University; Liverpool UK
| | - Neil R. W. Martin
- Musculoskeletal Biology Research Group, School of Sport, Exercise, and Health Sciences; Loughborough University; Loughborough UK
| | - Adam P. Sharples
- Stem Cells, Ageing, and Molecular Physiology (SCAMP) Unit, Exercise Metabolism and Adaptation Research group, Research Institute for Sport and Exercise Sciences (RISES), School of Sport and Exercise Sciences; Liverpool John Moores University; Liverpool UK
| |
Collapse
|
11
|
Smith AS, Passey SL, Martin NR, Player DJ, Mudera V, Greensmith L, Lewis MP. Creating Interactions between Tissue-Engineered Skeletal Muscle and the Peripheral Nervous System. Cells Tissues Organs 2016; 202:143-158. [PMID: 27825148 PMCID: PMC5175300 DOI: 10.1159/000443634] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2015] [Indexed: 12/22/2022] Open
Abstract
Effective models of mammalian tissues must allow and encourage physiologically (mimetic) correct interactions between co-cultured cell types in order to produce culture microenvironments as similar as possible to those that would normally occur in vivo. In the case of skeletal muscle, the development of such a culture model, integrating multiple relevant cell types within a biomimetic scaffold, would be of significant benefit for investigations into the development, functional performance, and pathophysiology of skeletal muscle tissue. Although some work has been published regarding the behaviour of in vitro muscle models co-cultured with organotypic slices of CNS tissue or with stem cell-derived neurospheres, little investigation has so far been made regarding the potential to maintain isolated motor neurons within a 3D biomimetic skeletal muscle culture platform. Here, we review the current state of the art for engineering neuromuscular contacts in vitro and provide original data detailing the development of a 3D collagen-based model for the co-culture of primary muscle cells and motor neurons. The devised culture system promotes increased myoblast differentiation, forming arrays of parallel, aligned myotubes on which areas of nerve-muscle contact can be detected by immunostaining for pre- and post-synaptic proteins. Quantitative RT-PCR results indicate that motor neuron presence has a positive effect on myotube maturation, suggesting neural incorporation influences muscle development and maturation in vitro. The importance of this work is discussed in relation to other published neuromuscular co-culture platforms along with possible future directions for the field.
Collapse
Affiliation(s)
- Alec S.T. Smith
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, London, UK
- Arthritis Research UK Centre for Sport, Exercise and Osteoarthritis, National Centre for Sport and Exercise Medicine (NCSEM) England, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
- Department of Bioengineering, University of Washington, Seattle, Wash., USA
| | - Samantha L. Passey
- Arthritis Research UK Centre for Sport, Exercise and Osteoarthritis, National Centre for Sport and Exercise Medicine (NCSEM) England, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
- Department of Pharmacology and Therapeutics, University of Melbourne, Melbourne, Vic., Australia
| | - Neil R.W. Martin
- Arthritis Research UK Centre for Sport, Exercise and Osteoarthritis, National Centre for Sport and Exercise Medicine (NCSEM) England, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Darren J. Player
- Arthritis Research UK Centre for Sport, Exercise and Osteoarthritis, National Centre for Sport and Exercise Medicine (NCSEM) England, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Vivek Mudera
- Division of Surgery and Interventional Science, UCL Institute of Orthopaedics and Musculoskeletal Science, London, UK
| | - Linda Greensmith
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, London, UK
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, UK
| | - Mark P. Lewis
- Arthritis Research UK Centre for Sport, Exercise and Osteoarthritis, National Centre for Sport and Exercise Medicine (NCSEM) England, School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
- *Prof. Mark P. Lewis, School of Sport, Exercise and Health Sciences, Loughborough University, Ashby Road, Loughborough LE11 3TU (UK), E-Mail
| |
Collapse
|
12
|
Heher P, Maleiner B, Prüller J, Teuschl AH, Kollmitzer J, Monforte X, Wolbank S, Redl H, Rünzler D, Fuchs C. A novel bioreactor for the generation of highly aligned 3D skeletal muscle-like constructs through orientation of fibrin via application of static strain. Acta Biomater 2015; 24:251-65. [PMID: 26141153 DOI: 10.1016/j.actbio.2015.06.033] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 06/10/2015] [Accepted: 06/29/2015] [Indexed: 01/31/2023]
Abstract
The generation of functional biomimetic skeletal muscle constructs is still one of the fundamental challenges in skeletal muscle tissue engineering. With the notion that structure strongly dictates functional capabilities, a myriad of cell types, scaffold materials and stimulation strategies have been combined. To further optimize muscle engineered constructs, we have developed a novel bioreactor system (MagneTissue) for rapid engineering of skeletal muscle-like constructs with the aim to resemble native muscle in terms of structure, gene expression profile and maturity. Myoblasts embedded in fibrin, a natural hydrogel that serves as extracellular matrix, are subjected to mechanical stimulation via magnetic force transmission. We identify static mechanical strain as a trigger for cellular alignment concomitant with the orientation of the scaffold into highly organized fibrin fibrils. This ultimately yields myotubes with a more mature phenotype in terms of sarcomeric patterning, diameter and length. On the molecular level, a faster progression of the myogenic gene expression program is evident as myogenic determination markers MyoD and Myogenin as well as the Ca(2+) dependent contractile structural marker TnnT1 are significantly upregulated when strain is applied. The major advantage of the MagneTissue bioreactor system is that the generated tension is not exclusively relying on the strain generated by the cells themselves in response to scaffold anchoring but its ability to subject the constructs to individually adjustable strain protocols. In future work, this will allow applying mechanical stimulation with different strain regimes in the maturation process of tissue engineered constructs and elucidating the role of mechanotransduction in myogenesis. STATEMENT OF SIGNIFICANCE Mechanical stimulation of tissue engineered skeletal muscle constructs is a promising approach to increase tissue functionality. We have developed a novel bioreactor-based 3D culture system, giving the user the possibility to apply different strain regimes like static, cyclic or ramp strain to myogenic precursor cells embedded in a fibrin scaffold. Application of static mechanical strain leads to alignment of fibrin fibrils along the axis of strain and concomitantly to highly aligned myotube formation. Additionally, the pattern of myogenic gene expression follows the temporal progression observed in vivo with a more thorough induction of the myogenic program when static strain is applied. Ultimately, the strain protocol used in this study results in a higher degree of muscle maturity demonstrated by enhanced sarcomeric patterning and increased myotube diameter and length. The introduced bioreactor system enables new possibilities in muscle tissue engineering as longer cultivation periods and different strain applications will yield tissue engineered muscle-like constructs with improved characteristics in regard to functionality and biomimicry.
Collapse
|
13
|
Qazi TH, Mooney DJ, Pumberger M, Geissler S, Duda GN. Biomaterials based strategies for skeletal muscle tissue engineering: existing technologies and future trends. Biomaterials 2015; 53:502-21. [PMID: 25890747 DOI: 10.1016/j.biomaterials.2015.02.110] [Citation(s) in RCA: 262] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 02/18/2015] [Accepted: 02/24/2015] [Indexed: 12/20/2022]
Abstract
Skeletal muscles have a robust capacity to regenerate, but under compromised conditions, such as severe trauma, the loss of muscle functionality is inevitable. Research carried out in the field of skeletal muscle tissue engineering has elucidated multiple intrinsic mechanisms of skeletal muscle repair, and has thus sought to identify various types of cells and bioactive factors which play an important role during regeneration. In order to maximize the potential therapeutic effects of cells and growth factors, several biomaterial based strategies have been developed and successfully implemented in animal muscle injury models. A suitable biomaterial can be utilized as a template to guide tissue reorganization, as a matrix that provides optimum micro-environmental conditions to cells, as a delivery vehicle to carry bioactive factors which can be released in a controlled manner, and as local niches to orchestrate in situ tissue regeneration. A myriad of biomaterials, varying in geometrical structure, physical form, chemical properties, and biofunctionality have been investigated for skeletal muscle tissue engineering applications. In the current review, we present a detailed summary of studies where the use of biomaterials favorably influenced muscle repair. Biomaterials in the form of porous three-dimensional scaffolds, hydrogels, fibrous meshes, and patterned substrates with defined topographies, have each displayed unique benefits, and are discussed herein. Additionally, several biomaterial based approaches aimed specifically at stimulating vascularization, innervation, and inducing contractility in regenerating muscle tissues are also discussed. Finally, we outline promising future trends in the field of muscle regeneration involving a deeper understanding of the endogenous healing cascades and utilization of this knowledge for the development of multifunctional, hybrid, biomaterials which support and enable muscle regeneration under compromised conditions.
Collapse
Affiliation(s)
- Taimoor H Qazi
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Germany; Berlin-Brandenburg School for Regenerative Therapies, Berlin, Germany.
| | - David J Mooney
- School of Engineering and Applied Sciences, Harvard University, Cambridge, USA.
| | - Matthias Pumberger
- Berlin-Brandenburg School for Regenerative Therapies, Berlin, Germany; Center for Musculoskeletal Surgery, Charitè - Universitätsmedizin Berlin, Germany.
| | - Sven Geissler
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Germany; Berlin-Brandenburg School for Regenerative Therapies, Berlin, Germany; Berlin-Brandenburg Center for Regenerative Therapies, Berlin, Germany.
| | - Georg N Duda
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Germany; Berlin-Brandenburg School for Regenerative Therapies, Berlin, Germany; Berlin-Brandenburg Center for Regenerative Therapies, Berlin, Germany.
| |
Collapse
|
14
|
Abstract
The British Orthodontic Society invites outstanding contributors from the field of Orthodontics to give the guest lecture in memory of George Northcroft. In 2005 the guest lecturer was Professor Nigel Hunt. The article that follows was presented as the Northcroft Memorial Lecture 2005 at the World Orthodontic Congress, Paris.
Collapse
Affiliation(s)
- Nigel Hunt
- UCL Eastman Dental Institute, London, UK.
| | | | | | | |
Collapse
|
15
|
Acute mechanical overload increases IGF-I and MMP-9 mRNA in 3D tissue-engineered skeletal muscle. Biotechnol Lett 2014; 36:1113-24. [PMID: 24563297 DOI: 10.1007/s10529-014-1464-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 01/09/2014] [Indexed: 01/24/2023]
Abstract
Skeletal muscle (SkM) is a tissue that responds to mechanical load following both physiological (exercise) or pathophysiological (bed rest) conditions. The heterogeneity of human samples and the experimental and ethical limitations of animal studies provide a rationale for the study of SkM plasticity in vitro. Many current in vitro approaches of mechanical loading of SkM disregard the three-dimensional (3D) structure in vivo. Tissue engineered 3D SkM, that displays highly aligned and differentiated myotubes, was used to investigate mechano-regulated gene transcription of genes implicated in hypertrophy/atrophy. Static loading (STL) and ramp loading (RPL) at 10 % strain for 60 min were used as mechano-stimulation with constructs sampled immediately for RNA extraction. STL increased IGF-I mRNA compared to both RPL and CON (control, p = 0.003 and 0.011 respectively) whilst MMP-9 mRNA increased in STL and RPL compared to CON (both p < 0.05). IGFBP-2 mRNA was differentially regulated in RPL and STL compared to CON (p = 0.057), whilst a reduction in IGFBP-5 mRNA was found for STL and RPL compared to CON (both p < 0.05). There was no effect in the expression of putative atrophic genes, myostatin, MuRF-1 and MAFBx (all p > 0.05). These data demonstrate a transcriptional signature associated with SkM hypertrophy within a tissue-engineered model that more greatly recapitulates the in vivo SkM structure compared previously published studies.
Collapse
|
16
|
Regulation of tissue fibrosis by the biomechanical environment. BIOMED RESEARCH INTERNATIONAL 2013; 2013:101979. [PMID: 23781495 PMCID: PMC3679815 DOI: 10.1155/2013/101979] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 05/10/2013] [Indexed: 12/21/2022]
Abstract
The biomechanical environment plays a fundamental role in embryonic development, tissue maintenance, and pathogenesis. Mechanical forces play particularly important roles in the regulation of connective tissues including not only bone and cartilage but also the interstitial tissues of most organs. In vivo studies have correlated changes in mechanical load to modulation of the extracellular matrix and have indicated that increased mechanical force contributes to the enhanced expression and deposition of extracellular matrix components or fibrosis. Pathological fibrosis contributes to dysfunction of many organ systems. A variety of in vitro models have been utilized to evaluate the effects of mechanical force on extracellular matrix-producing cells. In general, application of mechanical stretch, fluid flow, and compression results in increased expression of extracellular matrix components. More recent studies have indicated that tissue rigidity also provides profibrotic signals to cells. The mechanisms whereby cells detect mechanical signals and transduce them into biochemical responses have received considerable attention. Cell surface receptors for extracellular matrix components and intracellular signaling pathways are instrumental in the mechanotransduction process. Understanding how mechanical signals are transmitted from the microenvironment will identify novel therapeutic targets for fibrosis and other pathological conditions.
Collapse
|
17
|
Stretching skeletal muscle in vitro: does it replicate in vivo physiology? Biotechnol Lett 2011; 33:1513-21. [DOI: 10.1007/s10529-011-0610-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 03/30/2011] [Indexed: 10/18/2022]
|
18
|
Elliott NT, Yuan F. A review of three-dimensional in vitro tissue models for drug discovery and transport studies. J Pharm Sci 2010; 100:59-74. [PMID: 20533556 DOI: 10.1002/jps.22257] [Citation(s) in RCA: 318] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 05/04/2010] [Indexed: 12/12/2022]
Abstract
The use of animal models in drug discovery studies presents issues with feasibility and ethical concerns. To address these limitations, in vitro tissue models have been developed to provide a means for systematic, repetitive, and quantitative investigation of drugs. By eliminating or reducing the need for animal subjects, these models can serve as platforms for more tightly controlled, high-throughput screening of drugs and for pharmacokinetic and pharmacodynamic analyses of drugs. The focus of this review is three-dimensional (3D) tissue models that can capture cell-cell and cell-matrix interactions. Compared to the 2D culture of cell monolayers, 3D models more closely mimic native tissues since the cellular microenvironment established in the 3D models often plays a significant role in disease progression and cellular responses to drugs. A growing body of research has been published in the literature, which highlights the benefits of the 3D in vitro models of various tissues. This review provides an overview of some successful 3D in vitro models that have been developed to mimic liver, breast, cardiac, muscle, bone, and corneal tissues as well as malignant tissues in solid tumors.
Collapse
Affiliation(s)
- Nelita T Elliott
- Department of Biomedical Engineering, Duke University, 136 Hudson Hall, PO Box 90281, Durham, North Carolina 27708, USA
| | | |
Collapse
|
19
|
Smith AS, Shah R, Hunt NP, Lewis MP. The Role of Connective Tissue and Extracellular Matrix Signaling in Controlling Muscle Development, Function, and Response to Mechanical Forces. Semin Orthod 2010. [DOI: 10.1053/j.sodo.2010.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
20
|
Pang Q, Zu JW, Siu GM, Li RK. Design and Development of a Novel Biostretch Apparatus for Tissue Engineering. J Biomech Eng 2009; 132:014503. [DOI: 10.1115/1.3005154] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A uniaxial cyclic stretch apparatus is designed and developed for tissue engineering research. The biostretch apparatus employs noncontact electromagnetic force to uniaxially stretch a rectangular Gelfoam® or RTV silicon scaffold. A reliable controller is implemented to control four stretch parameters independently: extent, frequency, pattern, and duration of the stretch. The noncontact driving force together with the specially designed mount allow researchers to use standard Petri dishes and commercially available CO2 incubators to culture an engineered tissue patch under well-defined mechanical conditions. The culture process is greatly simplified over existing processes. Further, beyond traditional uniaxial stretch apparatuses, which provide stretch by fixing one side of the scaffolds and stretching the other side, the new apparatus can also apply uniaxial stretch from both ends simultaneously. Using the biostretch apparatus, the distributions of the strain on the Gelfoam® and GE RTV 6166 silicon scaffolds are quantitatively analyzed.
Collapse
Affiliation(s)
- Qiming Pang
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King’s College Road, Toronto, ON, M5S 3G8, Canada
| | - Jean W. Zu
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King’s College Road, Toronto, ON, M5S 3G8, Canada
| | - Geoffrey M. Siu
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King’s College Road, Toronto, ON, M5S 3G8, Canada
| | - Ren-Ke Li
- Department of Surgery, University of Toronto, 5 King’s College Road, Toronto, ON, M5S 3G8, Canada
| |
Collapse
|
21
|
Boonen KJ, Post MJ. The Muscle Stem Cell Niche: Regulation of Satellite Cells During Regeneration. TISSUE ENGINEERING PART B-REVIEWS 2008; 14:419-31. [DOI: 10.1089/ten.teb.2008.0045] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Kristel J.M. Boonen
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Mark J. Post
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
- Department of Physiology, CARIM, Maastricht University, Maastricht, The Netherlands
| |
Collapse
|
22
|
Brady MA, Lewis MP, Mudera V. Synergy between myogenic and non-myogenic cells in a 3D tissue-engineered craniofacial skeletal muscle construct. J Tissue Eng Regen Med 2008; 2:408-17. [DOI: 10.1002/term.112] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
23
|
Lygoe KA, Wall I, Stephens P, Lewis MP. Role of vitronectin and fibronectin receptors in oral mucosal and dermal myofibroblast differentiation. Biol Cell 2008; 99:601-14. [PMID: 17516912 DOI: 10.1042/bc20070008] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND INFORMATION The activation of fibroblasts into myofibroblasts is a crucial event in healing that is linked to remodelling and scar formation, therefore we determined whether regulation of myofibroblast differentiation via integrins might affect wound healing responses in populations of patient-matched HOFs (human oral fibroblasts) compared with HDFs (human dermal fibroblasts). RESULTS Both the HOF and HDF cell types underwent TGF-beta1 (transforming growth factor-beta1)-induced myofibroblastic differentiation [upregulation of the expression of alpha-sma (alpha-smooth muscle actin)], although analysis of unstimulated cells indicated that HOFs contained higher basal levels of alpha-sma than HDFs (P<0.05). Functional blocking antibodies against the integrin subunits alpha 5 (fibronectin) or alpha v (vitronectin) were used to determine whether the effects of TGF-beta1 were regulated via integrin signalling pathways. alpha-sma expression in both HOFs and HDFs was down-regulated by antibodies against both alpha 5 and alpha v. Functionally, TGF-beta1 inhibited cell migration in an in vitro wound model and increased the contraction of collagen gels. Greater contraction was evident for HOFs compared with HDFs, both with and without stimulation by TGF-beta1 (P<0.05). When TGF-beta1-stimulated cells were incubated with blocking antibodies against alpha 5 and alpha v, gel contraction was decreased to that of non-stimulated cells; however, blocking alpha v or alpha 5 could not restore cellular migration in both HOFs and HDFs. CONCLUSIONS Despite intrinsic differences in their basal state, the cellular events associated with TGF-beta1-induced myofibroblastic differentiation are common to both HOFs and HDFs, and appear to require differential integrin usage; up-regulation of alpha-sma expression and increases in collagen gel contraction are vitronectin- and fibronectin-receptor-dependent processes, whereas wound re-population is not.
Collapse
Affiliation(s)
- Kate A Lygoe
- Division of Biomaterials and Tissue Engineering, Eastman Dental Institute, University College London, 256 Grays Inn Road, London WC1X 8LD, UK
| | | | | | | |
Collapse
|
24
|
Yamada M, Sankoda Y, Tatsumi R, Mizunoya W, Ikeuchi Y, Sunagawa K, Allen RE. Matrix metalloproteinase-2 mediates stretch-induced activation of skeletal muscle satellite cells in a nitric oxide-dependent manner. Int J Biochem Cell Biol 2008; 40:2183-91. [DOI: 10.1016/j.biocel.2008.02.017] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2007] [Revised: 01/30/2008] [Accepted: 02/18/2008] [Indexed: 11/29/2022]
|
25
|
Marquette ML, Byerly D, Sognier M. A novel in vitro three-dimensional skeletal muscle model. In Vitro Cell Dev Biol Anim 2007; 43:255-63. [PMID: 17786532 DOI: 10.1007/s11626-007-9054-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Accepted: 07/25/2007] [Indexed: 01/21/2023]
Abstract
A novel three-dimensional (3D) skeletal muscle model composed of C2C12 mouse myoblasts is described. This model was generated by cultivating myoblasts in suspension using the rotary cell culture system (RCCS), a unique culture environment. Single-cell suspensions of myoblasts were seeded at 5 x 10(5)/ml in growth medium without exogenous support structures or substrates. Cell aggregation occurred in both RCCS and suspension control (SC) conditions within 12 h but occurred more rapidly in the SC at all time intervals examined. RCCS-cultured myoblasts fused and differentiated into a 3D construct without serum deprivation or alterations. Syncitia were quantified at 3 and 6+ d in stained thin sections. A significantly greater number of syncitia was found at 6+ d in the RCCS cultures compared to the SC. The majority of syncitia were localized to the periphery of the cell constructs for all treatments. The expression of sarcomeric myosin heavy chain (MHC) was localized at or near the periphery of the 3D construct. The majority of MHC was associated with the large cells (syncitia) of the 6+-d aggregates. These results show, for the first time, that myoblasts form syncitia and express MHC in the presence of growth factors and without the use of exogenous supports or substrates. This model test system is useful for investigating initial cell binding, myoblast fusion and syncitia formation, and differentiation processes.
Collapse
Affiliation(s)
- Michele L Marquette
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA.
| | | | | |
Collapse
|
26
|
Hunt N, Shah R, Sinanan A, Lewis M. [Muscular interference in malocclusion: present concepts of the role of the muscles in the etiology and therapy of malocclusion]. Orthod Fr 2007; 78:79-88. [PMID: 17580061 DOI: 10.1051/orthodfr:2007008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Nigel Hunt
- UCL Eastman Dental Institute, 256 Gray's Inn Road, London, Angleterre, UK.
| | | | | | | |
Collapse
|
27
|
Shelton L, Rada JS. Effects of cyclic mechanical stretch on extracellular matrix synthesis by human scleral fibroblasts. Exp Eye Res 2006; 84:314-22. [PMID: 17123515 PMCID: PMC2583333 DOI: 10.1016/j.exer.2006.10.004] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Revised: 09/29/2006] [Accepted: 10/04/2006] [Indexed: 01/02/2023]
Abstract
In order to understand the effect of mechanical strain on scleral extracellular matrix remodeling, human scleral fibroblasts were subjected to equibiaxial stretch in vitro and the expression of proteoglycans, metalloproteinases (MMPs) and tissue inhibitor of metalloproteinase-2 (TIMP-2) were evaluated. Isolated human scleral fibroblasts were seeded onto flexible bottom culture plates, and subjected to a cyclic stretch regimen of 15% equibiaxial stretch for 45 s followed by 15s of rest for 6-48 h in the presence of 35SO4. Newly synthesized proteoglycans were measured in the medium by CPC precipitation of radiolabelled glycosaminoglycans. MMP-2 activity and expression levels were measured in the medium by, Western blot, gel zymography and real-time PCR. Steady state levels of TIMP-2 mRNA and membrane-type MMP, MT1-MMP (MMP-14) mRNA were measured in the cell layer using real-time PCR. The predominant gelatinolytic enzyme secreted by scleral fibroblasts was the pro-enzyme form of MMP-2 (ProMMP-2). Mechanical stretch resulted in a significant increase of ProMMP-2 after 12 and 48 h (+76.28%, p<0.05; +19.56%, p<0.01, respectively). Mechanical stretch significantly increased the production of the active form of MMP-2 (ActiveMMP-2) after 48 h (+59.72%, p<0.05) and decreased levels of TIMP-2 mRNA (-22%, p<0.05). The rate of scleral proteoglycan synthesis and the steady state levels of MMP-2 and MMP-14 mRNA were not significantly affected by mechanical stretch. These results suggest that mechanical strain stimulates the activation of MMP-2 by scleral fibroblasts, possibly through increased levels of ProMMP-2 and reduced levels of TIMP-2. Increased levels of ActiveMMP-2 in the sclera would be expected to contribute to scleral extracellular matrix degradation, scleral thinning and possible ocular ectasia.
Collapse
Affiliation(s)
- Lilian Shelton
- Department of Cell Biology, University of Oklahoma Health Science Center, 940 Stanton L. Young Boulevard, BMSB, Room 553, Oklahoma City, OK 73103, USA.
| | | |
Collapse
|
28
|
Karamichos D, Brown RA, Mudera V. Complex dependence of substrate stiffness and serum concentration on cell-force generation. J Biomed Mater Res A 2006; 78:407-15. [PMID: 16715519 DOI: 10.1002/jbm.a.30814] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Collagen is a widely used biomaterial in tissue engineering. Mechanical stimulation of cell-seeded collagen constructs and its effects on cell orientation, intracellular signaling, and molecular responses have been reported. Our aim was to study the transfer of applied mechanical load to resident cells in 3D collagen constructs. Stainless steel markers were embedded in constructs as reporters of micromovement and uniaxial (0-15%) strain was applied. Cell-seeded collagen constructs were also subjected to (0-15%) uniaxial strain and material responses recorded. The viscoelastic properties of collagen resulted in comparatively small movement of the marker bars relative to gel deformation. Cell seeding density of 1 million/mL had no significant effect on the viscoelastic properties of collagen for the range of strain tested. Our findings indicate that viscoelastic properties of collagen result in minimal force transfer of applied loads as recorded by movement of stainless steel markers. At higher strain rates as collagen got stiffer the movement decreased. These findings indicate that as cell-seeded collagen constructs mature in a bioreactor and become stiffer due to ECM production/deposition, mechanical stimulation will have to be tailored over time to account for increased stiffness of constructs in vitro to elicit predictable and consistent cellular responses.
Collapse
Affiliation(s)
- D Karamichos
- UCL, Tissue Repair and Engineering Centre, Institute of Orthopaedics and Musculoskeletal Sciences, Stanmore, London, HA7 4LP, United Kingdom
| | | | | |
Collapse
|
29
|
Yamada M, Tatsumi R, Kikuiri T, Okamoto S, Nonoshita S, Mizunoya W, Ikeuchi Y, Shimokawa H, Sunagawa K, Allen RE. Matrix metalloproteinases are involved in mechanical stretch–induced activation of skeletal muscle satellite cells. Muscle Nerve 2006; 34:313-9. [PMID: 16810685 DOI: 10.1002/mus.20601] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
When skeletal muscle is stretched or injured, myogenic satellite cells are activated to enter the cell cycle. This process depends on nitric oxide (NO) production, release of hepatocyte growth factor (HGF) from the extracellular matrix, and presentation of HGF to the c-met receptor. Experiments reported herein provide new evidence that matrix metalloproteinases (MMPs) are involved in the NO-dependent release of HGF in vitro. When rat satellite cells were treated with 10 ng/ml recombinant tissue inhibitor-1 of MMPs (TIMP-1) and subjected to treatments that induce activation in vitro, i.e., sodium nitroprusside (SNP) of an NO donor or mechanical cyclic stretch, the activation response was inhibited. In addition, conditioned medium generated by cultures treated with TIMP-1 plus SNP or mechanical stretch failed to activate cultured satellite cells and did not contain HGF. Moreover, NO(x) assay demonstrated that TIMP-1 does not impair NO synthase activity of stretched satellite cell cultures. Therefore, results from these experiments provide strong evidence that MMPs mediate HGF release from the matrix and that this step in the pathway is downstream from NO synthesis.
Collapse
Affiliation(s)
- Michiko Yamada
- Department of Bioscience and Biotechnology, Kyushu University, Hakozaki, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|