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Warneke K, Lohmann LH, Plöschberger G, Konrad A. Critical evaluation and recalculation of current systematic reviews with meta-analysis on the effects of acute and chronic stretching on passive properties and passive peak torque. Eur J Appl Physiol 2024:10.1007/s00421-024-05564-6. [PMID: 39066912 DOI: 10.1007/s00421-024-05564-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Accepted: 07/09/2024] [Indexed: 07/30/2024]
Abstract
PURPOSE Muscle, tendon, and muscle-tendon unit (MTU) stiffness as well as passive peak torque (PPT) or delayed stretching pain sensation are typical explanatory approaches for stretching adaptations. However, in literature, differences in the study inclusion, as well as applying meta-analytical models without accounting for intrastudy dependency of multiple and heteroscedasticity of data bias the current evidence. Furthermore, most of the recent analyses neglected to investigate PPT adaptations and further moderators. METHODS The presented review used the recommended meta-analytical calculation method to investigate the effects of stretching on stiffness as well as on passive torque parameters using subgroup analyses for stretching types, stretching duration, and supervision. RESULTS Chronic stretching reduced muscle stiffness ( - 0.38, p = 0.01) overall, and also for the supervised ( - 0.49, p = 0.004) and long static stretching interventions ( - 0.61, p < 0.001), while the unsupervised and short duration subgroups did not reach the level of significance (p = 0.21, 0.29). No effects were observed for tendon stiffness or for subgroups (e.g., long-stretching durations). Chronic PPT (0.55, p = 0.005) in end ROM increased. Only long-stretching durations sufficiently decreased muscle stiffness acutely. No effects could be observed for acute PPT. CONCLUSION While partially in accordance with previous literature, the results underline the relevance of long-stretching durations when inducing changes in passive properties. Only four acute PPT in end ROM studies were eligible, while a large number were excluded as they provided mathematical models and/or lacked control conditions, calling for further randomized controlled trials on acute PPT effects.
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Affiliation(s)
- Konstantin Warneke
- Institute of Human Movement Science, Sport and Health, Karl-Franzens University of Graz, Mozartgasse 14, 8010, Graz, Austria.
- Institute of Sport Science, University of Klagenfurt, Klagenfurt am Wörthersee, Austria.
| | - Lars Hubertus Lohmann
- Department of Human Motion Science and Exercise Physiology, University of Jena, Jena, Germany
| | - Gerit Plöschberger
- Institute of Human Movement Science, Sport and Health, Karl-Franzens University of Graz, Mozartgasse 14, 8010, Graz, Austria
- Institute of Sport Science, University of Klagenfurt, Klagenfurt am Wörthersee, Austria
| | - Andreas Konrad
- Institute of Human Movement Science, Sport and Health, Karl-Franzens University of Graz, Mozartgasse 14, 8010, Graz, Austria
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Warneke K, Behm DG, Alizadeh S, Hillebrecht M, Konrad A, Wirth K. Discussing Conflicting Explanatory Approaches in Flexibility Training Under Consideration of Physiology: A Narrative Review. Sports Med 2024; 54:1785-1799. [PMID: 38819597 PMCID: PMC11258068 DOI: 10.1007/s40279-024-02043-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2024] [Indexed: 06/01/2024]
Abstract
The mechanisms underlying range of motion enhancements via flexibility training discussed in the literature show high heterogeneity in research methodology and study findings. In addition, scientific conclusions are mostly based on functional observations while studies considering the underlying physiology are less common. However, understanding the underlying mechanisms that contribute to an improved range of motion through stretching is crucial for conducting comparable studies with sound designs, optimising training routines and accurately interpreting resulting outcomes. While there seems to be no evidence to attribute acute range of motion increases as well as changes in muscle and tendon stiffness and pain perception specifically to stretching or foam rolling, the role of general warm-up effects is discussed in this paper. Additionally, the role of mechanical tension applied to greater muscle lengths for range of motion improvement will be discussed. Thus, it is suggested that physical training stressors can be seen as external stimuli that control gene expression via the targeted stimulation of transcription factors, leading to structural adaptations due to enhanced protein synthesis. Hence, the possible role of serial sarcomerogenesis in altering pain perception, reducing muscle stiffness and passive torque, or changes in the optimal joint angle for force development is considered as well as alternative interventions with a potential impact on anabolic pathways. As there are limited possibilities to directly measure serial sarcomere number, longitudinal muscle hypertrophy remains without direct evidence. The available literature does not demonstrate the necessity of only using specific flexibility training routines such as stretching to enhance acute or chronic range of motion.
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Affiliation(s)
- Konstantin Warneke
- Institute of Human Movement Science, Sport and Health, University of Graz, Graz, Austria.
- Department of Movement Sciences, Institute of Sport Science, University of Klagenfurt, Universitatsstraße 65, 9020, Klagenfurt Am Wörthersee, Austria.
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, Canada.
| | - David G Behm
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Shahab Alizadeh
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, Canada
- Human Performance Lab, Department of Kinesiology, University of Calgary, Calgary, AB, Canada
| | - Martin Hillebrecht
- University Sports Center, Carl Von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Andreas Konrad
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, Canada
- University Sports Center, Carl Von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Klaus Wirth
- University of Applied Sciences Wiener Neustadt, Vienna, Austria
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Warneke K, Lohmann LH, Wilke J. Effects of Stretching or Strengthening Exercise on Spinal and Lumbopelvic Posture: A Systematic Review with Meta-Analysis. SPORTS MEDICINE - OPEN 2024; 10:65. [PMID: 38834878 DOI: 10.1186/s40798-024-00733-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 05/22/2024] [Indexed: 06/06/2024]
Abstract
BACKGROUND Abnormal posture (e.g. loss of lordosis) has been associated with the occurrence of musculoskeletal pain. Stretching tight muscles while strengthening the antagonists represents the most common method to treat the assumed muscle imbalance. However, despite its high popularity, there is no quantitative synthesis of the available evidence examining the effectiveness of the stretch-and-strengthen approach. METHODS A systematic review with meta-analysis was conducted, searching PubMed, Web of Science and Google Scholar. We included controlled clinical trials investigating the effects of stretching or strengthening on spinal and lumbopelvic posture (e.g., pelvic tilt, lumbar lordosis, thoracic kyphosis, head tilt) in healthy individuals. Effect sizes were pooled using robust variance estimation. To rate the certainty about the evidence, the GRADE approach was applied. RESULTS A total of 23 studies with 969 participants were identified. Neither acute (d = 0.01, p = 0.97) nor chronic stretching (d=-0.19, p = 0.16) had an impact on posture. Chronic strengthening was associated with large improvements (d=-0.83, p = 0.01), but no study examined acute effects. Strengthening was superior (d = 0.81, p = 0.004) to stretching. Sub-analyses found strengthening to be effective in the thoracic and cervical spine (d=-1.04, p = 0.005) but not in the lumbar and lumbopelvic region (d=-0.23, p = 0.25). Stretching was ineffective in all locations (p > 0.05). CONCLUSION Moderate-certainty evidence does not support the use of stretching as a treatment of muscle imbalance. In contrast, therapists should focus on strengthening programs targeting weakened muscles.
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Affiliation(s)
- Konstantin Warneke
- Institute of Sport Science, Department of Movement Sciences, Alpen-Adrian-University Klagenfurt, Klagenfurt, Austria
| | - Lars Hubertus Lohmann
- Department of Human Movement Science and Exercise Physiology, Institute of Sport Science, Friedrich Schiller University, Jena, Germany.
| | - Jan Wilke
- Institute of Sport Science, Department of Movement Sciences, Alpen-Adrian-University Klagenfurt, Klagenfurt, Austria
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Wohlann T, Warneke K, Kalder V, Behm DG, Schmidt T, Schiemann S. Influence of 8-weeks of supervised static stretching or resistance training of pectoral major muscles on maximal strength, muscle thickness and range of motion. Eur J Appl Physiol 2024; 124:1885-1893. [PMID: 38240811 PMCID: PMC11129965 DOI: 10.1007/s00421-023-05413-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 12/29/2023] [Indexed: 05/28/2024]
Abstract
OBJECTIVES Current research suggests static stretch-induced maximal strength increases and muscle hypertrophy with potential to substitute resistance-training routines. However, most studies investigated the plantar flexors. This study explored the effects of a static stretching program on maximal strength, hypertrophy and flexibility of the pectoralis major and compared the effects with those of traditional resistance training. METHODS Eighty-one (81) active participants were allocated to either a static stretching, strength-training or control group. Pectoralis stretching was applied 15 min/day, 4 days per week for 8 weeks, while resistance training trained 3 days per week, 5 × 12 repetitions. RESULTS There was an increase in all parameters (strength: p < 0.001, ƞ2 = 0.313, muscle thickness: p < 0.001, ƞ2 = 0.157-0.264, flexibility: p < 0.001, ƞ2 = 0.316) and a time*group interaction (strength: p = 0.001, ƞ2 = 0.154, muscle thickness: p = 0.008-0.001, ƞ2 = 0.117-0.173, flexibility: p < 0.001, ƞ2 = 0.267). Post-hoc testing showed no difference between both intervention groups regarding maximal strength and muscle thickness (p = 0.905-0.983, d = 0.036-0.087), while flexibility increased in the stretching group (p = 0.001, d = 0.789). CONCLUSION Stretching showed increases in maximal strength and hypertrophy, which were comparable with commonly used resistance training. Based on current literature, the influence of mechanical tension as the underlying mechanism is discussed. Furthermore, as equipment and comparatively long stretching durations are requested to induce meaningful strength increases in recreationally active participants, practical application seems limited to special circumstances.
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Affiliation(s)
- Tim Wohlann
- Institute for Exercise, Sport and Health, Leuphana University, Lüneburg, Germany.
- Institute of Sport Science, University of Oldenburg, Oldenburg, Germany.
| | - Konstantin Warneke
- Institute of Sport Science, Alpen-Adria-University Klagenfurt, Klagenfurt Am Wörthersee, Austria
| | - Vincent Kalder
- Institute of Sport Science, University of Oldenburg, Oldenburg, Germany
| | - David G Behm
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Tobias Schmidt
- Department of Sport Science, Medical School Hamburg, Hamburg, Germany
| | - Stephan Schiemann
- Institute for Exercise, Sport and Health, Leuphana University, Lüneburg, Germany
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Avci O, Röhrle O. Determining a musculoskeletal system's pre-stretched state using continuum-mechanical forward modelling and joint range optimization. Biomech Model Mechanobiol 2024; 23:1031-1053. [PMID: 38619712 PMCID: PMC11101507 DOI: 10.1007/s10237-024-01821-x] [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: 08/03/2023] [Accepted: 01/04/2024] [Indexed: 04/16/2024]
Abstract
The subject-specific range of motion (RoM) of a musculoskeletal joint system is balanced by pre-tension levels of individual muscles, which affects their contraction capability. Such an inherent pre-tension or pre-stretch of muscles is not measureable with in vivo experiments. Using a 3D continuum mechanical forward simulation approach for motion analysis of the musculoskeletal system of the forearm with 3 flexor and 2 extensor muscles, we developed an optimization process to determine the muscle fibre pre-stretches for an initial arm position, which is given human dataset. We used RoM values of a healthy person to balance the motion in extension and flexion. The performed sensitivity study shows that the fibre pre-stretches of the m. brachialis, m. biceps brachii and m. triceps brachii with 91 % dominate the objective flexion ratio, while m. brachiradialis and m. anconeus amount 7.8 % and 1.2 % . Within the multi-dimensional space of the surrogate model, 3D sub-spaces of primary variables, namely the dominant muscles and the global objective, flexion ratio, exhibit a path of optimal solutions. Within this optimal path, the muscle fibre pre-stretch of two flexors demonstrate a negative correlation, while, in contrast, the primary extensor, m. triceps brachii correlates positively to each of the flexors. Comparing the global optimum with four other designs along the optimal path, we saw large deviations, e.g., up to 15∘ in motion and up to 40% in muscle force. This underlines the importance of accurate determination of fibre pre-stretch in muscles, especially, their role in pathological muscular disorders and surgical applications such as free muscle or tendon transfer.
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Affiliation(s)
- Okan Avci
- Fraunhofer Institute for Manufacturing Engineering and Automation IPA, Nobelstr. 12, 70569, Stuttgart, Germany.
| | - Oliver Röhrle
- Institute of Modelling and Simulation for Biomechanical Systems and Cluster of Excellence for Simulation Technology, University of Stuttgart, Pfaffenwaldring 5a, 70569, Stuttgart, Germany
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Escobar-Huertas JF, Vaca-González JJ, Guevara JM, Ramirez-Martinez AM, Trabelsi O, Garzón-Alvarado DA. Duchenne and Becker muscular dystrophy: Cellular mechanisms, image analysis, and computational models: A review. Cytoskeleton (Hoboken) 2024; 81:269-286. [PMID: 38224155 DOI: 10.1002/cm.21826] [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: 05/24/2023] [Revised: 11/21/2023] [Accepted: 12/20/2023] [Indexed: 01/16/2024]
Abstract
The muscle is the principal tissue that is capable to transform potential energy into kinetic energy. This process is due to the transformation of chemical energy into mechanical energy to enhance the movements and all the daily activities. However, muscular tissues can be affected by some pathologies associated with genetic alterations that affect the expression of proteins. As the muscle is a highly organized structure in which most of the signaling pathways and proteins are related to one another, pathologies may overlap. Duchenne muscular dystrophy (DMD) is one of the most severe muscle pathologies triggering degeneration and muscle necrosis. Several mathematical models have been developed to predict muscle response to different scenarios and pathologies. The aim of this review is to describe DMD and Becker muscular dystrophy in terms of cellular behavior and molecular disorders and to present an overview of the computational models implemented to understand muscle behavior with the aim of improving regenerative therapy.
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Affiliation(s)
- J F Escobar-Huertas
- Numerical Methods and Modeling Research Group (GNUM), Universidad Nacional de Colombia, Bogotá, Colombia
- Université de technologie de Compiègne, CNRS, Biomechanics and Bioengineering, Centre de Recherche Royallieu, Compiègne Cedex, France
| | - Juan Jairo Vaca-González
- Escuela de pregrado, Dirección Académica, Vicerrectoría de Sede, Universidad Nacional de Colombia, Sede la Paz, Cesar, Colombia
| | - Johana María Guevara
- Institute for the Study of Inborn Errors of Metabolism, Pontificia Universidad Javeriana, Bogotá, Colombia
| | | | - Olfa Trabelsi
- Université de technologie de Compiègne, CNRS, Biomechanics and Bioengineering, Centre de Recherche Royallieu, Compiègne Cedex, France
| | - D A Garzón-Alvarado
- Numerical Methods and Modeling Research Group (GNUM), Universidad Nacional de Colombia, Bogotá, Colombia
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Warneke K, Freundorfer P, Plöschberger G, Behm DG, Konrad A, Schmidt T. Effects of chronic static stretching interventions on jumping and sprinting performance-a systematic review with multilevel meta-analysis. Front Physiol 2024; 15:1372689. [PMID: 38595642 PMCID: PMC11002243 DOI: 10.3389/fphys.2024.1372689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 03/13/2024] [Indexed: 04/11/2024] Open
Abstract
When improving athletic performance in sports with high-speed strength demands such as soccer, basketball, or track and field, the most common training method might be resistance training and plyometrics. Since a link between strength capacity and speed strength exists and recently published literature suggested chronic stretching routines may enhance maximum strength and hypertrophy, this review was performed to explore potential benefits on athletic performance. Based on current literature, a beneficial effect of static stretching on jumping and sprinting performance was hypothesized. A systematic literature search was conducted using PubMed, Web of Science and Google scholar. In general, 14 studies revealed 29 effect sizes (ES) (20 for jumping, nine for sprinting). Subgroup analyses for jump performance were conducted for short- long- and no stretch shortening cycle trials. Qualitative evaluation was supplemented by performing a multilevel meta-analysis via R (Package: metafor). Significant positive results were documented in six out of 20 jump tests and in six out of nine sprint tests, while two studies reported negative adaptations. Quantitative data analyses indicated a positive but trivial magnitude of change on jumping performance (ES:0.16, p = 0.04), while all subgroup analyses did not support a positive effect (p = 0.09-0.44). No significant influence of static stretching on sprint performance was obtained (p = 0.08). Stretching does not seem to induce a sufficient stimulus to meaningfully enhance jumping and sprinting performance, which could possibly attributed to small weekly training volumes or lack of intensity.
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Affiliation(s)
- Konstantin Warneke
- Institute of Human Movement Science, Sport and Health, University of Graz, Graz, Austria
- Institute of Sport Science, University of Klagenfurt, Klagenfurt am Wörthersee, Austria
| | - Patrik Freundorfer
- Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Gerit Plöschberger
- Institute of Sport Science, University of Klagenfurt, Klagenfurt am Wörthersee, Austria
| | - David G. Behm
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Andreas Konrad
- Institute of Human Movement Science, Sport and Health, University of Graz, Graz, Austria
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Tobias Schmidt
- Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Hamburg, Germany
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Cowburn J, Serrancolí G, Pavei G, Minetti A, Salo A, Colyer S, Cazzola D. A novel computational framework for the estimation of internal musculoskeletal loading and muscle adaptation in hypogravity. Front Physiol 2024; 15:1329765. [PMID: 38384800 PMCID: PMC10880100 DOI: 10.3389/fphys.2024.1329765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 01/08/2024] [Indexed: 02/23/2024] Open
Abstract
Introduction: Spaceflight is associated with substantial and variable musculoskeletal (MSK) adaptations. Characterisation of muscle and joint loading profiles can provide key information to better align exercise prescription to astronaut MSK adaptations upon return-to-Earth. A case-study is presented of single-leg hopping in hypogravity to demonstrate the additional benefit computational MSK modelling has when estimating lower-limb MSK loading. Methods: A single male participant performed single-leg vertical hopping whilst attached to a body weight support system to replicate five gravity conditions (0.17, 0.25, 0.37, 0.50, 1 g). Experimental joint kinematics, joint kinetics and ground reaction forces were tracked in a data-tracking direct collocation simulation framework. Ground reaction forces, sagittal plane hip, knee and ankle net joint moments, quadriceps muscle forces (Rectus Femoris and three Vasti muscles), and hip, knee and ankle joint reaction forces were extracted for analysis. Estimated quadriceps muscle forces were input into a muscle adaptation model to predict a meaningful increase in muscle cross-sectional area, defined in (DeFreitas et al., 2011). Results: Two distinct strategies were observed to cope with the increase in ground reaction forces as gravity increased. Hypogravity was associated with an ankle dominant strategy with increased range of motion and net plantarflexor moment that was not seen at the hip or knee, and the Rectus Femoris being the primary contributor to quadriceps muscle force. At 1 g, all three joints had increased range of motion and net extensor moments relative to 0.50 g, with the Vasti muscles becoming the main muscles contributing to quadriceps muscle force. Additionally, hip joint reaction force did not increase substantially as gravity increased, whereas the other two joints increased monotonically with gravity. The predicted volume of exercise needed to counteract muscle adaptations decreased substantially with gravity. Despite the ankle dominant strategy in hypogravity, the loading on the knee muscles and joint also increased, demonstrating this provided more information about MSK loading. Discussion: This approach, supplemented with muscle-adaptation models, can be used to compare MSK loading between exercises to enhance astronaut exercise prescription.
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Affiliation(s)
- James Cowburn
- Department for Health, University of Bath, Bath, United Kingdom
- Centre for the Analysis of Motion, Entertainment Research and Applications, University of Bath, Bath, United Kingdom
| | - Gil Serrancolí
- Department of Mechanical Engineering, Universitat Politècnica de Catalunya, Barcelona, Spain
| | - Gaspare Pavei
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Alberto Minetti
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Aki Salo
- Department for Health, University of Bath, Bath, United Kingdom
- Centre for the Analysis of Motion, Entertainment Research and Applications, University of Bath, Bath, United Kingdom
| | - Steffi Colyer
- Department for Health, University of Bath, Bath, United Kingdom
- Centre for the Analysis of Motion, Entertainment Research and Applications, University of Bath, Bath, United Kingdom
| | - Dario Cazzola
- Department for Health, University of Bath, Bath, United Kingdom
- Centre for the Analysis of Motion, Entertainment Research and Applications, University of Bath, Bath, United Kingdom
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Sayed RKA, Hibbert JE, Jorgenson KW, Hornberger TA. The Structural Adaptations That Mediate Disuse-Induced Atrophy of Skeletal Muscle. Cells 2023; 12:2811. [PMID: 38132132 PMCID: PMC10741885 DOI: 10.3390/cells12242811] [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: 11/11/2023] [Revised: 12/07/2023] [Accepted: 12/09/2023] [Indexed: 12/23/2023] Open
Abstract
The maintenance of skeletal muscle mass plays a fundamental role in health and issues associated with quality of life. Mechanical signals are one of the most potent regulators of muscle mass, with a decrease in mechanical loading leading to a decrease in muscle mass. This concept has been supported by a plethora of human- and animal-based studies over the past 100 years and has resulted in the commonly used term of 'disuse atrophy'. These same studies have also provided a great deal of insight into the structural adaptations that mediate disuse-induced atrophy. For instance, disuse results in radial atrophy of fascicles, and this is driven, at least in part, by radial atrophy of the muscle fibers. However, the ultrastructural adaptations that mediate these changes remain far from defined. Indeed, even the most basic questions, such as whether the radial atrophy of muscle fibers is driven by the radial atrophy of myofibrils and/or myofibril hypoplasia, have yet to be answered. In this review, we thoroughly summarize what is known about the macroscopic, microscopic, and ultrastructural adaptations that mediated disuse-induced atrophy and highlight some of the major gaps in knowledge that need to be filled.
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Affiliation(s)
- Ramy K. A. Sayed
- Department of Comparative Biosciences, University of Wisconsin—Madison, Madison, WI 53706, USA; (R.K.A.S.); (J.E.H.); (K.W.J.)
- School of Veterinary Medicine, University of Wisconsin—Madison, Madison, WI 53706, USA
- Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Sohag University, Sohag 82524, Egypt
| | - Jamie E. Hibbert
- Department of Comparative Biosciences, University of Wisconsin—Madison, Madison, WI 53706, USA; (R.K.A.S.); (J.E.H.); (K.W.J.)
- School of Veterinary Medicine, University of Wisconsin—Madison, Madison, WI 53706, USA
| | - Kent W. Jorgenson
- Department of Comparative Biosciences, University of Wisconsin—Madison, Madison, WI 53706, USA; (R.K.A.S.); (J.E.H.); (K.W.J.)
- School of Veterinary Medicine, University of Wisconsin—Madison, Madison, WI 53706, USA
| | - Troy A. Hornberger
- Department of Comparative Biosciences, University of Wisconsin—Madison, Madison, WI 53706, USA; (R.K.A.S.); (J.E.H.); (K.W.J.)
- School of Veterinary Medicine, University of Wisconsin—Madison, Madison, WI 53706, USA
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Warneke K, Lohmann LH, Lima CD, Hollander K, Konrad A, Zech A, Nakamura M, Wirth K, Keiner M, Behm DG. Physiology of Stretch-Mediated Hypertrophy and Strength Increases: A Narrative Review. Sports Med 2023; 53:2055-2075. [PMID: 37556026 PMCID: PMC10587333 DOI: 10.1007/s40279-023-01898-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2023] [Indexed: 08/10/2023]
Abstract
Increasing muscle strength and cross-sectional area is of crucial importance to improve or maintain physical function in musculoskeletal rehabilitation and sports performance. Decreases in muscular performance are experienced in phases of reduced physical activity or immobilization. These decrements highlight the need for alternative, easily accessible training regimens for a sedentary population to improve rehabilitation and injury prevention routines. Commonly, muscle hypertrophy and strength increases are associated with resistance training, typically performed in a training facility. Mechanical tension, which is usually induced with resistance machines and devices, is known to be an important factor that stimulates the underlying signaling pathways to enhance protein synthesis. Findings from animal studies suggest an alternative means to induce mechanical tension to enhance protein synthesis, and therefore muscle hypertrophy by inducing high-volume stretching. Thus, this narrative review discusses mechanical tension-induced physiological adaptations and their impact on muscle hypertrophy and strength gains. Furthermore, research addressing stretch-induced hypertrophy is critically analyzed. Derived from animal research, the stretching literature exploring the impact of static stretching on morphological and functional adaptations was reviewed and critically discussed. No studies have investigated the underlying physiological mechanisms in humans yet, and thus the underlying mechanisms remain speculative and must be discussed in the light of animal research. However, studies that reported functional and morphological increases in humans commonly used stretching durations of > 30 min per session of the plantar flexors, indicating the importance of high stretching volume, if the aim is to increase muscle mass and maximum strength. Therefore, the practical applicability seems limited to settings without access to resistance training (e.g., in an immobilized state at the start of rehabilitation), as resistance training seems to be more time efficient. Nevertheless, further research is needed to generate evidence in different human populations (athletes, sedentary individuals, and rehabilitation patients) and to quantify stretching intensity.
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Affiliation(s)
- Konstantin Warneke
- Institute for Exercise, Sport and Health, Leuphana University, Universitätsallee 1, 21335, Lüneburg, Deutschland, Germany.
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, Canada.
- Institute of Sport Science, Alpen-Adria University Klagenfurt, Klagenfurt, Germany.
| | - Lars H Lohmann
- University Sports Center, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Camila D Lima
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
| | - Karsten Hollander
- Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Andreas Konrad
- Institute of Human Movement Science, Sport and Health, University of Graz, Graz, Austria
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Astrid Zech
- Department of Human Motion Science and Exercise Physiology, Friedrich Schiller University, Jena, Germany
| | - Masatoshi Nakamura
- Faculty of Rehabilitation Sciences, Nishi Kyushu University, Ozaki, Kanzaki, Saga, Japan
| | - Klaus Wirth
- Institute of Sport Science, University of Applied Sciences Wiener Neustadt, Wiener Neustadt, Austria
| | - Michael Keiner
- Department of Sport Science, German University of Health and Sport, Ismaning, Germany
| | - David G Behm
- School of Human Kinetics and Recreation, Memorial University of Newfoundland, St. John's, NL, Canada
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Muellner M, Haffer H, Chiapparelli E, Dodo Y, Tan ET, Shue J, Zhu J, Sama AA, Cammisa FP, Girardi FP, Hughes AP. Differences in lumbar paraspinal muscle morphology in patients with sagittal malalignment undergoing posterior lumbar fusion surgery. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2022; 31:3109-3118. [PMID: 36038784 PMCID: PMC10585706 DOI: 10.1007/s00586-022-07351-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 07/13/2022] [Accepted: 08/06/2022] [Indexed: 06/15/2023]
Abstract
PURPOSE To investigate whether (1) there is a difference between patients with normal or sagittal spinal and spinopelvic malalignment in terms of their paraspinal muscle composition and (2) if sagittal malalignment can be predicted using muscle parameters. METHODS A retrospective review of patients undergoing posterior lumbar fusion surgery was conducted. A MRI-based muscle measurement technique was used to assess the cross-sectional area, the functional cross-sectional area, the intramuscular fat and fat infiltration (FI) for the psoas and the posterior paraspinal muscles (PPM). Intervertebral disc degeneration was graded for levels L1 to S1. Sagittal vertical axis (SVA; ≥ 50 mm defined as spinal malalignment), pelvic incidence (PI) and lumbar lordosis (LL) were measured, and PI-LL mismatch (PI-LL; ≥ 10° defined as spinopelvic malalignment) was calculated. A receiver operating characteristic (ROC) analysis was conducted to determine the specificity and sensitivity of the FIPPM for predicting sagittal malalignment. RESULTS One hundred and fifty patients were analysed. The PI-LL and SVA malalignment groups were found to have a significantly higher FIPPM (PI-LL:47.0 vs. 42.1%; p = 0.019; SVA: 47.7 vs. 41.8%; p = 0.040). ROC analysis predicted sagittal spinal malalignment using FIPPM (cut-off value 42.69%) with a sensitivity of 73.4% and a specificity of 54.1% with an area under the curve of 0.662. CONCLUSION Significant differences in the muscle composition between normal and malalignment groups with respect to FIPPM in both sagittal spinal and spinopelvic alignment were found. This work underlines the imminent impact of the paraspinal musculature on the sagittal alignment.
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Affiliation(s)
- Maximilian Muellner
- Spine Care Institute, Hospital for Special Surgery, Weill Cornell Medicine, 535 East 70th Street, New York City, NY, 10021, USA
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Henryk Haffer
- Spine Care Institute, Hospital for Special Surgery, Weill Cornell Medicine, 535 East 70th Street, New York City, NY, 10021, USA
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Erika Chiapparelli
- Spine Care Institute, Hospital for Special Surgery, Weill Cornell Medicine, 535 East 70th Street, New York City, NY, 10021, USA
| | - Yusuke Dodo
- Spine Care Institute, Hospital for Special Surgery, Weill Cornell Medicine, 535 East 70th Street, New York City, NY, 10021, USA
| | - Ek T Tan
- Department of Radiology and Imaging, Hospital for Special Surgery, New York City, NY, USA
| | - Jennifer Shue
- Spine Care Institute, Hospital for Special Surgery, Weill Cornell Medicine, 535 East 70th Street, New York City, NY, 10021, USA
| | - Jiaqi Zhu
- Biostatistics Core, Hospital for Special Surgery, Weill Cornell Medicine, New York City, NY, USA
| | - Andrew A Sama
- Spine Care Institute, Hospital for Special Surgery, Weill Cornell Medicine, 535 East 70th Street, New York City, NY, 10021, USA
| | - Frank P Cammisa
- Spine Care Institute, Hospital for Special Surgery, Weill Cornell Medicine, 535 East 70th Street, New York City, NY, 10021, USA
| | - Federico P Girardi
- Spine Care Institute, Hospital for Special Surgery, Weill Cornell Medicine, 535 East 70th Street, New York City, NY, 10021, USA
| | - Alexander P Hughes
- Spine Care Institute, Hospital for Special Surgery, Weill Cornell Medicine, 535 East 70th Street, New York City, NY, 10021, USA.
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12
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Xu J, Fu D, Peng Y, Yang P, Xiong R, Lei K, Guo L. A case report: anatomical translocation in tibial insertion of semitendinosus tendon after tibial lengthening. BMC Musculoskelet Disord 2022; 23:936. [PMID: 36303198 PMCID: PMC9615355 DOI: 10.1186/s12891-022-05890-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 10/16/2022] [Indexed: 11/23/2022] Open
Abstract
Background There is the most common method for arthroscopic anterior cruciate ligament (ACL) reconstruction by using the semitendinosus and gracilis tendons and single-tunnel technique. However, anatomic translocation of hamstring tendon attachment is very rare. Case presentation A 45-year-old male who need to receive right knee ACL reconstruction due to sprain injury while playing table tennis was found to have a translocation at tibial attachment of semitendinosus tendon. The tibial insertion of left semitendinosus was then explored by ultrasound and found to be identical to the contralateral limb. The patient has a history of bilateral tibial lengthening. Conclusions This is the first case as far as we know that reported anatomic translocation of the tibial attachment of the hamstring tendon after tibial lengthening. Surgeons should be aware of this specific situation when hamstring tendon need to be harvested to avoid unnecessary complications.
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Affiliation(s)
- Juncai Xu
- Center for Joint Surgery, Southwest Hospital, Army Medical University, Chongqing, 400038, China
| | - Dejie Fu
- Center for Joint Surgery, Southwest Hospital, Army Medical University, Chongqing, 400038, China
| | - Yang Peng
- Center for Joint Surgery, Southwest Hospital, Army Medical University, Chongqing, 400038, China
| | - Pengfei Yang
- Center for Joint Surgery, Southwest Hospital, Army Medical University, Chongqing, 400038, China
| | - Ran Xiong
- Center for Joint Surgery, Southwest Hospital, Army Medical University, Chongqing, 400038, China
| | - Kai Lei
- Center for Joint Surgery, Southwest Hospital, Army Medical University, Chongqing, 400038, China
| | - Lin Guo
- Center for Joint Surgery, Southwest Hospital, Army Medical University, Chongqing, 400038, China.
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13
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Villota-Narvaez Y, Garzón-Alvarado DA, Röhrle O, Ramírez-Martínez AM. Multi-scale mechanobiological model for skeletal muscle hypertrophy. Front Physiol 2022; 13:899784. [PMID: 36277181 PMCID: PMC9582841 DOI: 10.3389/fphys.2022.899784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 08/23/2022] [Indexed: 11/13/2022] Open
Abstract
Skeletal muscle adaptation is correlated to training exercise by triggering different signaling pathways that target many functions; in particular, the IGF1-AKT pathway controls protein synthesis and degradation. These two functions regulate the adaptation in size and strength of muscles. Computational models for muscle adaptation have focused on: the biochemical description of signaling pathways or the mechanical description of muscle function at organ scale; however, an interrelation between these two models should be considered to understand how an adaptation in muscle size affects the protein synthesis rate. In this research, a dynamical model for the IGF1-AKT signaling pathway is linked to a continuum-mechanical model describing the active and passive mechanical response of a muscle; this model is used to study the impact of the adaptive muscle geometry on the protein synthesis at the fiber scale. This new computational model links the signaling pathway to the mechanical response by introducing a growth tensor, and links the mechanical response to the signaling pathway through the evolution of the protein synthesis rate. The predicted increase in cross sectional area (CSA) due to an 8 weeks training protocol excellently agreed with experimental data. Further, our results show that muscle growth rate decreases, if the correlation between protein synthesis and CSA is negative. The outcome of this study suggests that multi-scale models coupling continuum mechanical properties and molecular functions may improve muscular therapies and training protocols.
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Affiliation(s)
- Yesid Villota-Narvaez
- Numerical Methods and Modeling Research Group (GNUM), Universidad Nacional de Colombia, Bogotá, Colombia
- Institute for Modelling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany
- *Correspondence: Yesid Villota-Narvaez ,
| | - Diego A. Garzón-Alvarado
- Numerical Methods and Modeling Research Group (GNUM), Universidad Nacional de Colombia, Bogotá, Colombia
- Biomimetics Laboratory, Instituto de Biotecnología (IBUN), Universidad Nacional de Colombia, Bogotá, Colombia
| | - Oliver Röhrle
- Institute for Modelling and Simulation of Biomechanical Systems, University of Stuttgart, Stuttgart, Germany
- Stuttgart Center for Simulation Sciences (SC SimTech), Stuttgart, Germany
| | - Angelica M. Ramírez-Martínez
- Biomimetics Laboratory, Instituto de Biotecnología (IBUN), Universidad Nacional de Colombia, Bogotá, Colombia
- Biomedical Engineering Department, Engineering Faculty, Universidad Militar Nueva Granada, Bogotá, Colombia
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14
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Hinks A, Jacob K, Mashouri P, Medak KD, Franchi MV, Wright DC, Brown SHM, Power GA. Influence of weighted downhill running training on serial sarcomere number and work loop performance in the rat soleus. Biol Open 2022; 11:276077. [PMID: 35876382 PMCID: PMC9346294 DOI: 10.1242/bio.059491] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 06/23/2022] [Indexed: 12/16/2022] Open
Abstract
Increased serial sarcomere number (SSN) has been observed in rats following downhill running training due to the emphasis on active lengthening contractions; however, little is known about the influence on dynamic contractile function. Therefore, we employed 4 weeks of weighted downhill running training in rats, then assessed soleus SSN and work loop performance. We hypothesised trained rats would produce greater net work output during work loops due to a greater SSN. Thirty-one Sprague-Dawley rats were assigned to a training or sedentary control group. Weight was added during downhill running via a custom-made vest, progressing from 5–15% body mass. Following sacrifice, the soleus was dissected, and a force-length relationship was constructed. Work loops (cyclic muscle length changes) were then performed about optimal muscle length (LO) at 1.5–3-Hz cycle frequencies and 1–7-mm length changes. Muscles were then fixed in formalin at LO. Fascicle lengths and sarcomere lengths were measured to calculate SSN. Intramuscular collagen content and crosslinking were quantified via a hydroxyproline content and pepsin-solubility assay. Trained rats had longer fascicle lengths (+13%), greater SSN (+8%), and a less steep passive force-length curve than controls (P<0.05). There were no differences in collagen parameters (P>0.05). Net work output was greater (+78–209%) in trained than control rats for the 1.5-Hz work loops at 1 and 3-mm length changes (P<0.05), however, net work output was more related to maximum specific force (R2=0.17-0.48, P<0.05) than SSN (R2=0.03-0.07, P=0.17-0.86). Therefore, contrary to our hypothesis, training-induced sarcomerogenesis likely contributed little to the improvements in work loop performance. This article has an associated First Person interview with the first author of the paper. Summary: An investigation of adaptations in mechanical function induced by a novel method of weighted downhill running training in rats, and the connections to adaptations in muscle architecture.
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Affiliation(s)
- Avery Hinks
- Department of Human Health and Nutritional Sciences, College of Biological Sciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Kaitlyn Jacob
- Department of Human Health and Nutritional Sciences, College of Biological Sciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Parastoo Mashouri
- Department of Human Health and Nutritional Sciences, College of Biological Sciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Kyle D Medak
- Department of Human Health and Nutritional Sciences, College of Biological Sciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Martino V Franchi
- Department of Biomedical Sciences, Neuromuscular Physiology Laboratory, University of Padua, Padua 35122, Italy
| | - David C Wright
- Department of Human Health and Nutritional Sciences, College of Biological Sciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada.,School of Kinesiology, Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Stephen H M Brown
- Department of Human Health and Nutritional Sciences, College of Biological Sciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
| | - Geoffrey A Power
- Department of Human Health and Nutritional Sciences, College of Biological Sciences, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1, Canada
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15
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Zhang Y, Wang L, Kang H, Lin CY, Fan Y. Applying exercise-mimetic engineered skeletal muscle model to interrogate the adaptive response of irisin to mechanical force. iScience 2022; 25:104135. [PMID: 35434556 PMCID: PMC9010619 DOI: 10.1016/j.isci.2022.104135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 02/28/2022] [Accepted: 03/17/2022] [Indexed: 11/30/2022] Open
Abstract
Physical exercise induces the secretion of irisin from contractile muscle into circulation; however, the adaptive response of irisin to mechanical stimulus in skeletal muscle in vitro remains numerously unknown. In an effort to investigate whether irisin is inducible in vitro, we developed a bioreactor consisting of a retractable mechanical force controller and a conditional tissue culture system. Upon this model, a distinguished surge of irisin was detected in stretched myotubes as cyclic strain initiated, and the surge was able to be stalled by knocking out FNDC5. Intriguingly, increased irisin secretory is associated with the shifts of MyHC isoforms from anaerobic type to aerobic type in myotubes. We further revealed that PGC-1α1 and PGC-1α4 mRNAs expression, rather than PGC-1α2 and PGC-1α3, contributed to the generation of irisin in myotubes during cyclic strain. Lastly, combined with co-culturing MC3T3 osteoblasts, we demonstrated the bioactivity of generated irisin, promoting the osteogenic differentiation. Irisin is producible in an exercise-mimetic engineered skeletal muscle model Enhanced irisin production in response to a long-term cyclic stretch PGC-1α1 and PGC-1α4 mRNAs expression contributed to the generation of irisin Demonstration that induced irisin in our model regulating osteoblasts as native ways
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Affiliation(s)
- Yuwei Zhang
- Key laboratory for Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Centre for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China
| | - Lizhen Wang
- Key laboratory for Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Centre for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China
| | - Hongyan Kang
- Key laboratory for Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Centre for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China
| | - Chia-Ying Lin
- Key laboratory for Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Centre for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China.,Department of Biomedical, Chemical & Environmental Engineering, University of Cincinnati, Cincinnati, USA.,Department of Orthopaedic Surgery, University of Cincinnati, Cincinnati, USA.,Department of Neurosurgery, University of Cincinnati, Cincinnati, USA
| | - Yubo Fan
- Key laboratory for Biomechanics and Mechanobiology of Ministry of Education, Beijing Advanced Innovation Centre for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China.,School of Engineering Medicine, Beihang University, Beijing 100083, China
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16
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Sibley LA, Broda N, Gross WR, Menezes AF, Embry RB, Swaroop VT, Chambers HG, Schipma MJ, Lieber RL, Domenighetti AA. Differential DNA methylation and transcriptional signatures characterize impairment of muscle stem cells in pediatric human muscle contractures after brain injury. FASEB J 2021; 35:e21928. [PMID: 34559924 DOI: 10.1096/fj.202100649r] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 08/11/2021] [Accepted: 08/31/2021] [Indexed: 12/26/2022]
Abstract
Limb contractures are a debilitating and progressive consequence of a wide range of upper motor neuron injuries that affect skeletal muscle function. One type of perinatal brain injury causes cerebral palsy (CP), which affects a child's ability to move and is often painful. While several rehabilitation therapies are used to treat contractures, their long-term effectiveness is marginal since such therapies do not change muscle biological properties. Therefore, new therapies based on a biological understanding of contracture development are needed. Here, we show that myoblast progenitors from contractured muscle in children with CP are hyperproliferative. This phenotype is associated with DNA hypermethylation and specific gene expression patterns that favor cell proliferation over quiescence. Treatment of CP myoblasts with 5-azacytidine, a DNA hypomethylating agent, reduced this epigenetic imprint to TD levels, promoting exit from mitosis and molecular mechanisms of cellular quiescence. Together with previous studies demonstrating reduction in myoblast differentiation, this suggests a mechanism of contracture formation that is due to epigenetic modifications that alter the myogenic program of muscle-generating stem cells. We suggest that normalization of DNA methylation levels could rescue myogenesis and promote regulated muscle growth in muscle contracture and thus may represent a new nonsurgical approach to treating this devastating neuromuscular condition.
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Affiliation(s)
| | | | | | | | - Ryan B Embry
- NUseq Core, Northwestern University, Chicago, Illinois, USA
| | - Vineeta T Swaroop
- Shirley Ryan AbilityLab, Chicago, Illinois, USA.,Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA
| | - Henry G Chambers
- Rady Children's Hospital and Health Center, San Diego, California, USA
| | - Matthew J Schipma
- Rady Children's Hospital and Health Center, San Diego, California, USA
| | - Richard L Lieber
- Shirley Ryan AbilityLab, Chicago, Illinois, USA.,Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, Illinois, USA.,Hines VA Medical Center, Maywood, Illinois, USA
| | - Andrea A Domenighetti
- Shirley Ryan AbilityLab, Chicago, Illinois, USA.,Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, Illinois, USA
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17
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Halle JL, Counts-Franch BR, Prince RM, Carson JA. The Effect of Mechanical Stretch on Myotube Growth Suppression by Colon-26 Tumor-Derived Factors. Front Cell Dev Biol 2021; 9:690452. [PMID: 34395422 PMCID: PMC8363303 DOI: 10.3389/fcell.2021.690452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 07/08/2021] [Indexed: 12/16/2022] Open
Abstract
Preclinical models and in vitro experiments have provided valuable insight into the regulation of cancer-induced muscle wasting. Colon-26 (C26) tumor cells induce cachexia in mice, and conditioned media (CM) from these cells promotes myotube atrophy and catabolic signaling. While mechanical stimuli can prevent some effects of tumor-derived factors on myotubes, the impact of mechanical signaling on tumor-derived factor regulation of myosin heavy chain (MyHC) expression is not well understood. Therefore, we examined the effects of stretch-induced mechanical signaling on C2C12 myotube growth and MyHC expression after C26 CM exposure. C26 CM was administered to myotubes on day 5 of differentiation for 48 h. During the last 4 or 24 h of C26 CM exposure, 5% static uniaxial stretch was administered. C26 CM suppressed myotube growth and MyHC protein and mRNA expression. Stretch for 24 h increased myotube size and prevented the C26 CM suppression of MyHC-Fast protein expression. Stretch did not change suppressed MyHC mRNA expression. Stretch for 24 h reduced Atrogin-1/MAFbx, MuRF-1, and LC3B II/I ratio and increased integrin β1D protein expression and the myogenin-to-MyoD protein ratio. Stretch in the last 4 h of CM increased ERK1/2 phosphorylation but did not alter the CM induction of STAT3 or p38 phosphorylation. These results provide evidence that in myotubes pre-incubated with CM, the induction of mechanical signaling can still provide a growth stimulus and preserve MyHC-Fast protein expression independent of changes in mRNA expression.
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Affiliation(s)
| | | | | | - James A. Carson
- Integrative Muscle Biology Laboratory, Division of Rehabilitation Sciences, College of Health Professions, University of Tennessee Health Science Center, Memphis, TN, United States
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18
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Lamsfuss J, Bargmann S. Skeletal muscle: Modeling the mechanical behavior by taking the hierarchical microstructure into account. J Mech Behav Biomed Mater 2021; 122:104670. [PMID: 34274750 DOI: 10.1016/j.jmbbm.2021.104670] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 05/05/2021] [Accepted: 06/26/2021] [Indexed: 11/28/2022]
Abstract
Skeletal muscles ensure the mobility of mammals and are complex natural fiber-matrix-composites with a hierarchical microstructure. In this work, we analyze the muscle's mechanical behavior on the level of fascicles and muscle fibers. We introduce continuum mechanics hyperelastic material models for the connective tissue endomysium and the embedded muscle fibers. The coupled electrical, chemical and mechanical processes taking place in activated contracting muscle fibers are captured including the temporal change of the activation level and the spatial propagation of the activation potential in fibers. In our model, we investigate the material behavior of fascicle, fiber and endomysium in the fiber direction and examine interactions between muscle fiber and endomysium by considering the temporal and spatial change of muscle fiber activation. In addition, a loading case of normal and shear forces is applied to analyze the fiber lifting force and the lifting height of unipennate muscles with different pennation angles. Moreover, the development of local stresses and strains in fibers and endomysium for different strains are studied. The simulation results allow to identify regions in high risk of damage. Optimal arrangements of unipennate muscle microstructure are found for either very small or very large pennation angles.
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Affiliation(s)
- Jens Lamsfuss
- Chair of Solid Mechanics, School of Mechanical and Safety Engineering, University of Wuppertal, Germany.
| | - Swantje Bargmann
- Chair of Solid Mechanics, School of Mechanical and Safety Engineering, University of Wuppertal, Germany; Wuppertal Center for Smart Materials, University of Wuppertal, Germany
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19
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Razavi MJ, Liu T, Wang X. Mechanism Exploration of 3-Hinge Gyral Formation and Pattern Recognition. Cereb Cortex Commun 2021; 2:tgab044. [PMID: 34377991 PMCID: PMC8343593 DOI: 10.1093/texcom/tgab044] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 06/22/2021] [Accepted: 06/24/2021] [Indexed: 11/12/2022] Open
Abstract
The 3-hinge gyral folding is the conjunction of gyrus crest lines from three different orientations. Previous studies have not explored the possible mechanisms of formation of such 3-hinge gyri, which are preserved across species in primate brains. We develop a biomechanical model to mimic the formation of 3-hinge patterns on a real brain and determine how special types of 3-hinge patterns form in certain areas of the model. Our computational and experimental imaging results show that most tertiary convolutions and exact locations of 3-hinge patterns after growth and folding are unpredictable, but they help explain the consistency of locations and patterns of certain 3-hinge patterns. Growing fibers within the white matter is posited as a determining factor to affect the location and shape of these 3-hinge patterns. Even if the growing fibers do not exert strong enough forces to guide gyrification directly, they still may seed a heterogeneous growth profile that leads to the formation of 3-hinge patterns in specific locations. A minor difference in initial morphology between two growing model brains can lead to distinct numbers and locations of 3-hinge patterns after folding.
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Affiliation(s)
- Mir Jalil Razavi
- Department of Mechanical Engineering, Binghamton University, Binghamton, NY 13902, USA
| | - Tianming Liu
- Cortical Architecture Imaging and Discovery Lab, Department of Computer Science and Bioimaging Research Center, The University of Georgia, Athens, GA 30602, USA
| | - Xianqiao Wang
- School of Environmental, Civil, Agricultural, and Mechanical Engineering, College of Engineering, the University of Georgia, Athens, GA 30602, USA
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20
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Millward DJ. Interactions between Growth of Muscle and Stature: Mechanisms Involved and Their Nutritional Sensitivity to Dietary Protein: The Protein-Stat Revisited. Nutrients 2021; 13:729. [PMID: 33668846 PMCID: PMC7996181 DOI: 10.3390/nu13030729] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 02/15/2021] [Accepted: 02/22/2021] [Indexed: 02/07/2023] Open
Abstract
Childhood growth and its sensitivity to dietary protein is reviewed within a Protein-Stat model of growth regulation. The coordination of growth of muscle and stature is a combination of genetic programming, and of two-way mechanical interactions involving the mechanotransduction of muscle growth through stretching by bone length growth, the core Protein-Stat feature, and the strengthening of bone through muscle contraction via the mechanostat. Thus, growth in bone length is the initiating event and this is always observed. Endocrine and cellular mechanisms of growth in stature are reviewed in terms of the growth hormone-insulin like growth factor-1 (GH-IGF-1) and thyroid axes and the sex hormones, which together mediate endochondral ossification in the growth plate and bone lengthening. Cellular mechanisms of muscle growth during development are then reviewed identifying (a) the difficulties posed by the need to maintain its ultrastructure during myofibre hypertrophy within the extracellular matrix and the concept of muscle as concentric "bags" allowing growth to be conceived as bag enlargement and filling, (b) the cellular and molecular mechanisms involved in the mechanotransduction of satellite and mesenchymal stromal cells, to enable both connective tissue remodelling and provision of new myonuclei to aid myofibre hypertrophy and (c) the implications of myofibre hypertrophy for protein turnover within the myonuclear domain. Experimental data from rodent and avian animal models illustrate likely changes in DNA domain size and protein turnover during developmental and stretch-induced muscle growth and between different muscle fibre types. Growth of muscle in male rats during adulthood suggests that "bag enlargement" is achieved mainly through the action of mesenchymal stromal cells. Current understanding of the nutritional regulation of protein deposition in muscle, deriving from experimental studies in animals and human adults, is reviewed, identifying regulation by amino acids, insulin and myofibre volume changes acting to increase both ribosomal capacity and efficiency of muscle protein synthesis via the mechanistic target of rapamycin complex 1 (mTORC1) and the phenomenon of a "bag-full" inhibitory signal has been identified in human skeletal muscle. The final section deals with the nutritional sensitivity of growth of muscle and stature to dietary protein in children. Growth in length/height as a function of dietary protein intake is described in the context of the breastfed child as the normative growth model, and the "Early Protein Hypothesis" linking high protein intakes in infancy to later adiposity. The extensive paediatric studies on serum IGF-1 and child growth are reviewed but their clinical relevance is of limited value for understanding growth regulation; a role in energy metabolism and homeostasis, acting with insulin to mediate adiposity, is probably more important. Information on the influence of dietary protein on muscle mass per se as opposed to lean body mass is limited but suggests that increased protein intake in children is unable to promote muscle growth in excess of that linked to genotypic growth in length/height. One possible exception is milk protein intake, which cohort and cross-cultural studies suggest can increase height and associated muscle growth, although such effects have yet to be demonstrated by randomised controlled trials.
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Affiliation(s)
- D Joe Millward
- Department of Nutritional Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, UK
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21
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Lee T, Holland MA, Weickenmeier J, Gosain AK, Tepole AB. The Geometry of Incompatibility in Growing Soft Tissues: Theory and Numerical Characterization. JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS 2021; 146:104177. [PMID: 34054143 PMCID: PMC8153650 DOI: 10.1016/j.jmps.2020.104177] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Tissues in vivo are not stress-free. As we grow, our tissues adapt to different physiological and disease conditions through growth and remodeling. This adaptation occurs at the microscopic scale, where cells control the microstructure of their immediate extracellular environment to achieve homeostasis. The local and heterogeneous nature of this process is the source of residual stresses. At the macroscopic scale, growth and remodeling can be accurately captured with the finite volume growth framework within continuum mechanics, which is akin to plasticity. The multiplicative split of the deformation gradient into growth and elastic contributions brings about the notion of incompatibility as a plausible description for the origin of residual stress. Here we define the geometric features that characterize incompatibility in biological materials. We introduce the geometric incompatibility tensor for different growth types, showing that the constraints associated with growth lead to specific patterns of the incompatibility metrics. To numerically investigate the distribution of incompatibility measures, we implement the analysis within a finite element framework. Simple, illustrative examples are shown first to explain the main concepts. Then, numerical characterization of incompatibility and residual stress is performed on three biomedical applications: brain atrophy, skin expansion, and cortical folding. Our analysis provides new insights into the role of growth in the development of tissue defects and residual stresses. Thus, we anticipate that our work will further motivate additional research to characterize residual stresses in living tissue and their role in development, disease, and clinical intervention.
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Affiliation(s)
- Taeksang Lee
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA
| | - Maria A Holland
- Aerospace & Mechanical Engineering, University of Notre Dame, Notre Dame, IN, USA
| | - Johannes Weickenmeier
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ, USA
| | - Arun K Gosain
- Lurie Children Hospital, Northwestern University, Chicago, IL, USA
| | - Adrian Buganza Tepole
- School of Mechanical Engineering, Purdue University, West Lafayette, IN, USA
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN, USA
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Chavoshnejad P, Li X, Zhang S, Dai W, Vasung L, Liu T, Zhang T, Wang X, Razavi MJ. Role of axonal fibers in the cortical folding patterns: A tale of variability and regularity. BRAIN MULTIPHYSICS 2021. [DOI: 10.1016/j.brain.2021.100029] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Jorgenson KW, Phillips SM, Hornberger TA. Identifying the Structural Adaptations that Drive the Mechanical Load-Induced Growth of Skeletal Muscle: A Scoping Review. Cells 2020; 9:cells9071658. [PMID: 32660165 PMCID: PMC7408414 DOI: 10.3390/cells9071658] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/06/2020] [Accepted: 07/07/2020] [Indexed: 12/21/2022] Open
Abstract
The maintenance of skeletal muscle mass plays a critical role in health and quality of life. One of the most potent regulators of skeletal muscle mass is mechanical loading, and numerous studies have led to a reasonably clear understanding of the macroscopic and microscopic changes that occur when the mechanical environment is altered. For instance, an increase in mechanical loading induces a growth response that is mediated, at least in part, by an increase in the cross-sectional area of the myofibers (i.e., myofiber hypertrophy). However, very little is known about the ultrastructural adaptations that drive this response. Even the most basic questions, such as whether mechanical load-induced myofiber hypertrophy is mediated by an increase in the size of the pre-existing myofibrils and/or an increase in the number myofibrils, have not been resolved. In this review, we thoroughly summarize what is currently known about the macroscopic, microscopic and ultrastructural changes that drive mechanical load-induced growth and highlight the critical gaps in knowledge that need to be filled.
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Affiliation(s)
- Kent W. Jorgenson
- School of Veterinary Medicine and the Department of Comparative Biosciences, University of Wisconsin, Madison, WI 53706, USA;
| | - Stuart M. Phillips
- Department of Kinesiology, McMaster University, Hamilton, ON L8S 4K1, Canada;
| | - Troy A. Hornberger
- School of Veterinary Medicine and the Department of Comparative Biosciences, University of Wisconsin, Madison, WI 53706, USA;
- Correspondence:
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Sensory regulation and mechanical effects of sustained high intensity stretching of the anterior compartment of the thigh. J Bodyw Mov Ther 2020; 24:18-25. [PMID: 32507143 DOI: 10.1016/j.jbmt.2020.02.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 02/16/2020] [Accepted: 02/24/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Ballet dancers, contortionists, gymnasts, or other sportspeople spend long hours performing stretches while training. Although most studies on stretching consider fascia lengthening to be difficult, athletes manage to lengthen their fascia. AIM To assess the relationship between lengthening fascial structures of the anterior compartment of the thigh and the self-reported sensation of discomfort and pain during a sustained and repeated high intensity stretch. METHODS Our analysis was based on the data of 7 high school male elite rugby players who completed 11 sessions of stretching (10-min quasi-static stretch of the rectus femoris and fascia lata, at the maximum intensity tolerated), performed twice per week. The measured outcomes included hip range of motion, the length of the structures of the anterior compartment, subjective pain and tension during the stretch, and the level of surface electromyography activity. Values were compared before and after completion of the 11 sessions. RESULTS Myofascial length increased by 1 cm. The necessary force applied increased from 124 to 164 N. However, the maximal tolerated stretching intensity did not change significantly (from 205 to 206 N). The increase in length was principally contributed by the rate of fascial creep upon force application, and not by contractile tissue. Subjective levels of tension were related to the stretching force applied and pain was related to the lengthening. CONCLUSION Sensations can be used to adjust the intensity and duration of stretching. Soft matter physics provides a new interpretation of fascia lengthening and strengthening during a high intensity stretch.
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Nuhmani S. Does soft tissue mobilization assist static stretching to improve hamstring flexibility? A randomized controlled trial. JOURNAL OF COMPLEMENTARY & INTEGRATIVE MEDICINE 2020; 17:/j/jcim.ahead-of-print/jcim-2019-0288/jcim-2019-0288.xml. [PMID: 32549127 DOI: 10.1515/jcim-2019-0288] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 12/19/2019] [Indexed: 11/15/2022]
Abstract
Objectives Objective of the study is to investigate whether Soft tissue mobilization (STM) can assist with static stretching to improve hamstring flexibly. Methods The design of the study was repeated measure design. The study was conducted at the physical therapy laboratory of Jamia Hamdard University, New Delhi. Participants included 78 healthy males with hamstring tightness, randomly assigned to either the control group (static stretching) or the experimental group (STM and static stretching). The experimental group received five sets of four different STM techniques, followed by two sets of 30-s static stretches 3 days per week over the course of 12 weeks. The control group received 5 min of sham ultrasound with an inactive probe prior to static stretching. Active knee extension test (AKE) was the outcome measure. Results Both groups showed significant improvement in AKE compared with the baseline measurements. With ingroup analysis showed a significant difference in AKE across all measured time periods (weeks 4, 8, and 12) with pre-test in both groups (p<0.05). No significant difference in AKE improvement was found between groups (p>0.05). Conclusion The results of this study show that STM prior to static stretching does not significantly improve hamstring flexibility among healthy individuals. Although this study cannot be generalized, the results may be useful for evidence-based practice in the management of hamstring tightness.
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Affiliation(s)
- Shibili Nuhmani
- Physical Therapy Department, College of Applied Medical Sciences, Imam Abdulrahman Bin Faisal University, P.O. Box 2435, Dammam, 31451, Saudi Arabia
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Peri D, Deville M, Poignard C, Signori E, Natalini R. Numerical optimization of plasmid DNA delivery combined with hyaluronidase injection for electroporation protocol. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2020; 186:105204. [PMID: 31760303 DOI: 10.1016/j.cmpb.2019.105204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 11/06/2019] [Accepted: 11/11/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND OBJECTIVE The paper focuses on the numerical strategies to optimize a plasmid DNA delivery protocol, which combines hyaluronidase and electroporation. METHODS A well-defined continuum mechanics model of muscle porosity and advanced numerical optimization strategies have been used, to propose a substantial improvement of a pre-existing experimental protocol of DNA transfer in mice. Our work suggests that a computational model might help in the definition of innovative therapeutic procedures, thanks to the fine tuning of all the involved experimental steps. This approach is particularly interesting in optimizing complex and costly protocols, to make in vivo DNA therapeutic protocols more effective. RESULTS Our preliminary work suggests that computational model might help in the definition of innovative therapeutic protocol, thanks to the fine tuning of all the involved operations. CONCLUSIONS This approach is particularly interesting in optimizing complex and costly protocols for which the number of degrees of freedom prevents a experimental test of the possible configuration.
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Affiliation(s)
- Daniele Peri
- CNR-IAC - National Research Council, Istituto per le Applicazioni del Calcolo "Mauro Picone" Via dei Taurini 19, Rome 00185, Italy.
| | - Manon Deville
- Team MONC, INRIA Bordeaux-Sud-Ouest, Institut de Mathématiques de Bordeaux, CNRS UMR 5251 & Université de Bordeaux, 351 cours de la Libération, Talence Cedex 33405, France
| | - Clair Poignard
- Team MONC, INRIA Bordeaux-Sud-Ouest, Institut de Mathématiques de Bordeaux, CNRS UMR 5251 & Université de Bordeaux, 351 cours de la Libération, Talence Cedex 33405, France
| | - Emanuela Signori
- CNR-IFT - National Research Council - Istituto di Farmacologia Traslazionale, Via Fosso del Cavaliere 100, Rome 00133, Italy.
| | - Roberto Natalini
- CNR-IAC - National Research Council, Istituto per le Applicazioni del Calcolo "Mauro Picone" Via dei Taurini 19, Rome 00185, Italy
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CORR Insights®: Does a Reduced Number of Muscle Stem Cells Impair the Addition of Sarcomeres and Recovery from a Skeletal Muscle Contracture? A Transgenic Mouse Model. Clin Orthop Relat Res 2020; 478:900-902. [PMID: 32118609 PMCID: PMC7282576 DOI: 10.1097/corr.0000000000001177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Cini A, de Vasconcelos GS, Soligo MC, Felappi C, Rodrigues R, Aurélio Vaz M, Lima CS. Comparison between 4 weeks passive static stretching and proprioceptive neuromuscular facilitation programmes on neuromuscular properties of hamstring muscles: a randomised clinical trial. INTERNATIONAL JOURNAL OF THERAPY AND REHABILITATION 2020. [DOI: 10.12968/ijtr.2018.0104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Background/aims Studies have shown the efficacy of stretching to increase the hip flexion range of motion but studies regarding its effects are not unanimous about the most efficient technique. The aim of this study was to compare the effect of two stretching techniques on the neuromuscular properties of the hamstring muscles. Methods A total of 18 women (aged 24 ± 2.52 years old) participated, and were divided into three groups: a control group, a passive static stretching group and a propioceptive neuromuscular facilitation stretching group. Evaluations of variables of the hamstring muscles were performed before and after the training period. The intervention was carried out for 30 seconds, three times a week for a total of 4 weeks. Results A significant difference was found in the range of motion in the passive static stretching group (pre=80.8° [±11.0] and post=94.5° [±10.2]; t(5)=−3.755; P=0.013) and in concentric torque (passive static stretching group – pre=66.3 Nm [±12.9] and post=70.0 Nm [±8.1]; t(5)=−1.267; P=0.023; propioceptive neuromuscular facilitation stretching group – pre=79.1 Nm [±12.7] and post=83.5 Nm [±11.6]; t(5)=−1.917; P=0.014; control group – pre=71.1 Nm [±10.1] and post=74.1 Nm [±14.6]; t(5)=−1.275; P=0.003). Conclusions Passive static stretching was superior to propioceptive neuromuscular facilitation when comparing the increase range of motion in hip flexion, even without neural and structural changes in hamstring muscles after a 4-week period.
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Affiliation(s)
- Anelize Cini
- School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Gabriela Souza de Vasconcelos
- School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Milena Caumo Soligo
- School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Cassiele Felappi
- School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Rodrigo Rodrigues
- School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Marco Aurélio Vaz
- School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Cláudia Silveira Lima
- School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
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Erlich A, Jones GW, Tisseur F, Moulton DE, Goriely A. The role of topology and mechanics in uniaxially growing cell networks. Proc Math Phys Eng Sci 2020; 476:20190523. [PMID: 32082058 PMCID: PMC7016545 DOI: 10.1098/rspa.2019.0523] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 12/10/2019] [Indexed: 01/18/2023] Open
Abstract
In biological systems, the growth of cells, tissues and organs is influenced by mechanical cues. Locally, cell growth leads to a mechanically heterogeneous environment as cells pull and push their neighbours in a cell network. Despite this local heterogeneity, at the tissue level, the cell network is remarkably robust, as it is not easily perturbed by changes in the mechanical environment or the network connectivity. Through a network model, we relate global tissue structure (i.e. the cell network topology) and local growth mechanisms (growth laws) to the overall tissue response. Within this framework, we investigate the two main mechanical growth laws that have been proposed: stress-driven or strain-driven growth. We show that in order to create a robust and stable tissue environment, networks with predominantly series connections are naturally driven by stress-driven growth, whereas networks with predominantly parallel connections are associated with strain-driven growth.
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Affiliation(s)
- Alexander Erlich
- Laboratoire Interdisciplinaire de Physique (LIPhy), Université Grenoble Alpes, CNRS, Grenoble 38000, France
| | - Gareth W. Jones
- School of Mathematics, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Françoise Tisseur
- School of Mathematics, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Derek E. Moulton
- Mathematical Institute, University of Oxford, Andrew Wiles Building, Woodstock Road, Oxford OX2 6GG, UK
| | - Alain Goriely
- Mathematical Institute, University of Oxford, Andrew Wiles Building, Woodstock Road, Oxford OX2 6GG, UK
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Bone Formation and Adaptive Morphology of the Anterior Tibial Muscle in 3-mm Daily Lengthening Using High-Fractional Automated Distraction and Osteosynthesis with the Ilizarov Apparatus Combined with Intramedullary Hydroxyapatite-Coated Wire. BIOMED RESEARCH INTERNATIONAL 2019; 2019:3241263. [PMID: 31119163 PMCID: PMC6500699 DOI: 10.1155/2019/3241263] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 03/15/2019] [Accepted: 04/01/2019] [Indexed: 01/17/2023]
Abstract
Purpose We studied osteogenesis and morphofunctional features of the anterior tibial muscle using 3-mm high-frequency automated lengthening with the Ilizarov apparatus alone and in combination with intramedullary nailing. Material and Methods Tibia was lengthened with a round-the-clock automated distractor at a 3-mm daily rate for 10 days in 16 mongrel dogs. In group 1 (n = 8), a 1.8-mm intramedullary titanium wire coated with hydroxyapatite was introduced into the tibial canal followed by Ilizarov frame mounting and transverse osteotomy of the diaphysis. Distraction mode was 0.025 mm x 120 increments a day. In group 2 (n = 8), distraction mode was the same but nailing was not used. Bone formation and the anterior tibial muscle were studied at two time points: (1) upon distraction completion; (2) three months after the apparatus removal. Bone formation was studied radiographically. Muscle preparations were examined histologically and stereomicroscopically. Results There was a threefold reduction in the distraction time in both groups. Consolidation took 13.83±4.02 days in group 1 and 33.7±2.4 days in group 2. Muscle macropreparations of the experimental limb in group 1 at study time points did not show significant differences from intact tissues. Muscle histostructure in both groups was characterized by activation of angiogenesis and myohistogenesis, but the volumetric density of microvessels in the lengthening phase was three times higher in group 1. Conclusion Combined technology significantly reduces the total lengthening procedure and does not compromise limb functions. Intramedullary HA-coated wires promote faster bone formation. The muscle was able to exhibit structural adaptation and plasticity of a restitution type.
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Sahli Costabal F, Choy JS, Sack KL, Guccione JM, Kassab GS, Kuhl E. Multiscale characterization of heart failure. Acta Biomater 2019; 86:66-76. [PMID: 30630123 DOI: 10.1016/j.actbio.2018.12.053] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 12/28/2018] [Accepted: 12/31/2018] [Indexed: 12/27/2022]
Abstract
Dilated cardiomyopathy is a progressive irreversible disease associated with contractile dysfunction and heart failure. During dilated cardiomyopathy, elevated diastolic wall strains trigger mechanotransduction pathways that initiate the addition of sarcomeres in series and an overall increase in myocyte length. At the whole organ level, this results in a chronic dilation of the ventricles, an increase in end diastolic and end systolic volumes, and a decrease in ejection fraction. However, how exactly changes in sarcomere number translate into changes in myocyte morphology, and how these cellular changes translate into ventricular dilation remains incompletely understood. Here we combined a chronic animal study, continuum growth modeling, and machine learning to quantify correlations between sarcomere dynamics, myocyte morphology, and ventricular dilation. In an eight-week long volume overload study of six pigs, we found that the average sarcomere number increased by +3.8%/week, from 47 to 62, resulting in a myocyte lengthening of +3.3%/week, from 85 to 108 μm, while the sarcomere length and myocyte width remained unchanged. At the same time, the average end diastolic volume increased by +6.0%/week. Using continuum growth modeling and Bayesian inference, we correlated alterations on the subcellular, cellular, and organ scales and found that the serial sarcomere number explained 88% of myocyte lengthening, which, in turn, explained 54% of cardiac dilation. Our results demonstrate that sarcomere number and myocyte length are closely correlated and constitute the major determinants of dilated heart failure. We anticipate our study to be a starting point for more sophisticated multiscale models of heart failure. Our study suggests that altering sarcomere turnover-and with it myocyte morphology and ventricular dimensions-could be a potential therapeutic target to attenuate or reverse the progression of heart failure. STATEMENT OF SIGNIFICANCE: Heart failure is a significant global health problem that affects more than 25 million people worldwide and increases in prevalence as the population ages. Heart failure has been studied excessively at various scales; yet, there is no compelling concept to connect knowledge from the subcellular, cellular, and organ level across the scales. Here we combined a chronic animal study, continuum growth modeling, and machine learning to quantify correlations between sarcomere dynamics, myocyte morphology, and ventricular dilation. We found that the serial sarcomere number explained 88% of myocyte lengthening, which, in turn, explained 54% of cardiac dilation. Our results show that sarcomere number and myocyte length are closely correlated and constitute the major determinants of dilated heart failure. This suggests that altering the sarcomere turnover-and with it myocyte morphology and ventricular dimensions-could be a potential therapeutic target to attenuate or reverse heart failure.
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Affiliation(s)
- F Sahli Costabal
- Departments of Mechanical Engineering & Bioengineering, Stanford University, CA, USA
| | - J S Choy
- California Medical Innovations Institute, Inc., San Diego, CA, USA
| | - K L Sack
- Department of Human Biology, University of Cape Town, Cape Town, South Africa
| | - J M Guccione
- Department of Surgery, University of California at San Francisco, San Francisco, CA, USA
| | - G S Kassab
- California Medical Innovations Institute, Inc., San Diego, CA, USA
| | - E Kuhl
- Departments of Mechanical Engineering & Bioengineering, Stanford University, CA, USA.
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He F, Chuang CC, Zhou T, Jiang Q, Sedlock DA, Zuo L. Redox correlation in muscle lengthening and immune response in eccentric exercise. PLoS One 2018; 13:e0208799. [PMID: 30589838 PMCID: PMC6307742 DOI: 10.1371/journal.pone.0208799] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 11/26/2018] [Indexed: 11/19/2022] Open
Abstract
This study was designed to examine the potential involvement of reactive oxygen species in skeletal muscle dysfunction linked with stretching in a mouse model and to explore the effects of combined antioxidant intake on peripheral leukocyte apoptosis following eccentrically-biased downhill runs in human subjects. In the mouse model, diaphragmatic muscle was stretched by 30% of its optimal length, followed by 5-min contraction. Muscle function and extracellular reactive oxygen species release was measured ex vivo. In human models, participants performed two trials of downhill running either with or without antioxidant supplementation, followed by apoptotic assay of inflammatory cells in the blood. The results showed that stretch led to decreased muscle function and prominent ROS increase during muscle contraction. In human models, we observed an elevation in circulating leukocyte apoptosis 24-48 hours following acute downhill runs. However, there is an attenuated leukocyte apoptosis following the second bout of downhill run. Interestingly, the combination of ascorbic acid (vitamin C) and α-tocopherol (vitamin E) supplementation attenuated the decrease in B-cell lymphoma 2 (Bcl-2) at 24 hours following acute downhill running. These data collectively suggest that significant ROS formation can be induced by muscle-lengthening associated with eccentric exercise, which is accompanied by compromised muscle function. The combination of antioxidants supplementation appears to have a protective role via the attenuation of decrease in anti-apoptotic protein.
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Affiliation(s)
- Feng He
- Department of Health and Kinesiology, College of Health and Human Sciences, Purdue University, West Lafayette, IN, United States of America
- Department of Kinesiology, California State University-Chico, Chico, CA, United States of America
| | - Chia-Chen Chuang
- Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States of America
- Interdisciplinary Biophysics Graduate Program, The Ohio State University, Columbus, OH, United States of America
| | - Tingyang Zhou
- Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States of America
- Interdisciplinary Biophysics Graduate Program, The Ohio State University, Columbus, OH, United States of America
| | - Qing Jiang
- Department of Nutrition Science, College of Health and Human Science, Purdue University, West Lafayette, IN, United States of America
| | - Darlene A. Sedlock
- Department of Health and Kinesiology, College of Health and Human Sciences, Purdue University, West Lafayette, IN, United States of America
- * E-mail: (LZ); (DAS)
| | - Li Zuo
- Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States of America
- Interdisciplinary Biophysics Graduate Program, The Ohio State University, Columbus, OH, United States of America
- Molecular Physiology and Biophysics Laboratory, College of Arts and Sciences, University of Maine, Presque Isle, ME, United States of America
- * E-mail: (LZ); (DAS)
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Braeu FA, Aydin RC, Cyron CJ. Anisotropic stiffness and tensional homeostasis induce a natural anisotropy of volumetric growth and remodeling in soft biological tissues. Biomech Model Mechanobiol 2018; 18:327-345. [PMID: 30413985 DOI: 10.1007/s10237-018-1084-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 10/16/2018] [Indexed: 12/20/2022]
Abstract
Growth in soft biological tissues in general results in anisotropic changes of the tissue geometry. It remains a key challenge in biomechanics to understand, quantify, and predict this anisotropy. In this paper, we demonstrate that anisotropic tissue stiffness and the well-known mechanism of tensional homeostasis induce a natural anisotropy of the geometric changes resulting from volumetric growth in soft biological tissues. As a rule of thumb, this natural anisotropy makes differential tissue volume elements dilate mainly in the direction(s) of lowest stiffness. This simple principle is shown to explain the experimentally observed growth behavior in a host of different soft biological tissues without relying on any additional heuristic assumptions or quantities (such as ad hoc defined growth tensors).
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Affiliation(s)
- F A Braeu
- Institute for Computational Mechanics, Technical University of Munich, Munich, Germany
| | - R C Aydin
- Institute for Computational Mechanics, Technical University of Munich, Munich, Germany
| | - Christian J Cyron
- Institute of Continuum Mechanics and Materials Mechanics, Hamburg University of Technology, Eissendorfer Strasse 42, 21073, Hamburg, Germany. .,Institute of Materials Research, Materials Mechanics, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany.
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A Continuum Mechanics Model of Enzyme-Based Tissue Degradation in Cancer Therapies. Bull Math Biol 2018; 80:3184-3226. [DOI: 10.1007/s11538-018-0515-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Accepted: 09/24/2018] [Indexed: 12/29/2022]
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van der Pijl R, Strom J, Conijn S, Lindqvist J, Labeit S, Granzier H, Ottenheijm C. Titin-based mechanosensing modulates muscle hypertrophy. J Cachexia Sarcopenia Muscle 2018; 9:947-961. [PMID: 29978560 PMCID: PMC6204599 DOI: 10.1002/jcsm.12319] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/30/2018] [Accepted: 05/22/2018] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Titin is an elastic sarcomeric filament that has been proposed to play a key role in mechanosensing and trophicity of muscle. However, evidence for this proposal is scarce due to the lack of appropriate experimental models to directly test the role of titin in mechanosensing. METHODS We used unilateral diaphragm denervation (UDD) in mice, an in vivo model in which the denervated hemidiaphragm is passively stretched by the contralateral, innervated hemidiaphragm and hypertrophy rapidly occurs. RESULTS In wildtype mice, the denervated hemidiaphragm mass increased 48 ± 3% after 6 days of UDD, due to the addition of both sarcomeres in series and in parallel. To test whether titin stiffness modulates the hypertrophy response, RBM20ΔRRM and TtnΔIAjxn mouse models were used, with decreased and increased titin stiffness, respectively. RBM20ΔRRM mice (reduced stiffness) showed a 20 ± 6% attenuated hypertrophy response, whereas the TtnΔIAjxn mice (increased stiffness) showed an 18 ± 8% exaggerated response after UDD. Thus, muscle hypertrophy scales with titin stiffness. Protein expression analysis revealed that titin-binding proteins implicated previously in muscle trophicity were induced during UDD, MARP1 & 2, FHL1, and MuRF1. CONCLUSIONS Titin functions as a mechanosensor that regulates muscle trophicity.
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Affiliation(s)
- Robbert van der Pijl
- Department of Cellular and Molecular MedicineUniversity of ArizonaTucsonAZUSA
- Dept of PhysiologyVU University Medical CenterAmsterdamThe Netherlands
| | - Joshua Strom
- Department of Cellular and Molecular MedicineUniversity of ArizonaTucsonAZUSA
| | - Stefan Conijn
- Dept of PhysiologyVU University Medical CenterAmsterdamThe Netherlands
| | - Johan Lindqvist
- Department of Cellular and Molecular MedicineUniversity of ArizonaTucsonAZUSA
| | - Siegfried Labeit
- Department of Integrative PathophysiologyMedical Faculty MannheimMannheimGermany
- Myomedix GmbHNeckargemuendGermany
| | - Henk Granzier
- Department of Cellular and Molecular MedicineUniversity of ArizonaTucsonAZUSA
| | - Coen Ottenheijm
- Department of Cellular and Molecular MedicineUniversity of ArizonaTucsonAZUSA
- Dept of PhysiologyVU University Medical CenterAmsterdamThe Netherlands
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36
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Flück M, Viecelli C, Bapst AM, Kasper S, Valdivieso P, Franchi MV, Ruoss S, Lüthi JM, Bühler M, Claassen H, Hoppeler H, Gerber C. Knee Extensors Muscle Plasticity Over a 5-Years Rehabilitation Process After Open Knee Surgery. Front Physiol 2018; 9:1343. [PMID: 30337877 PMCID: PMC6178139 DOI: 10.3389/fphys.2018.01343] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 09/06/2018] [Indexed: 01/26/2023] Open
Abstract
We investigated molecular and cellular parameters which set metabolic and mechanical functioning of knee extensor muscles in the operated and contralateral control leg of 9 patients with a chronically insufficient anterior cruciate ligament (ACL; 26.6 ± 8.3 years, 8 males, 1 female) after open reconstructive surgery (week 0), after ambulant physiotherapy under cast immobilization (week 9), succeeding rehabilitation training (up to week 26), and subsequent voluntary physical activity (week 260). Clinical indices of knee function in the operated leg were improved at 52 weeks and remained at a comparable level at week 260. CSA of the quadriceps (-18%), MCSA of muscle fibers (-24%), and capillary-to-fiber ratio (-24%) in m. vastus lateralis from the ACL insufficient leg were lower at week 0 than reference values in the contralateral leg at week 260. Slow type fiber percentage (-35%) and mitochondrial volume density (-39%) were reduced in m. vastus lateralis from the operated leg at weeks 9 and 26. Composition alterations in the operated leg exceeded those in the contralateral leg and, with the exception of the volume density of subsarcolemmal mitochondria, returned to the reference levels at week 260. Leg-specific deterioration of metabolic characteristics in the vasti from the operated leg was reflected by the down-regulation of mitochondrial respiration complex I-III markers (-41-57%) at week 9. After rehabilitation training at week 26, the specific Y397 phosphorylation of focal adhesion kinase (FAK), which is a proxy for mechano-regulation, was elevated by 71% in the operated leg but not in the contralateral leg, which had performed strengthening type exercise during ambulant physiotherapy. Total FAK protein and Y397 phosphorylation levels were lowered in both legs at week 26 resulting in positive correlations with mitochondrial volume densities and mitochondrial protein levels. The findings emphasize that a loss of mechanical and metabolic characteristics in knee extensor muscle remains detectable years after untreated ACL rupture, which may be aggravated in the post-operative phase by the deterioration of slow-oxidative characteristics after reconstruction due to insufficient load-bearing muscle activity. The reestablishment of muscle composition subsequent to years of voluntary physical activity reinforces that slow-to-fast fiber transformation is reversible in humans.
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Affiliation(s)
- Martin Flück
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Claudio Viecelli
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Andreas M Bapst
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Stephanie Kasper
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Paola Valdivieso
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Martino V Franchi
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Severin Ruoss
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Jean-Marc Lüthi
- Department of Orthopedic Surgery, Inselspital Bern, Bern, Switzerland
| | - Martin Bühler
- Department of Orthopedic Surgery, Inselspital Bern, Bern, Switzerland
| | | | - Hans Hoppeler
- Department of Anatomy, University of Bern, Bern, Switzerland
| | - Christian Gerber
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.,Department of Orthopedic Surgery, Inselspital Bern, Bern, Switzerland
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37
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Biomaterials in Tendon and Skeletal Muscle Tissue Engineering: Current Trends and Challenges. MATERIALS 2018; 11:ma11071116. [PMID: 29966303 PMCID: PMC6073924 DOI: 10.3390/ma11071116] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 06/20/2018] [Accepted: 06/25/2018] [Indexed: 12/17/2022]
Abstract
Tissue engineering is a promising approach to repair tendon and muscle when natural healing fails. Biohybrid constructs obtained after cells’ seeding and culture in dedicated scaffolds have indeed been considered as relevant tools for mimicking native tissue, leading to a better integration in vivo. They can also be employed to perform advanced in vitro studies to model the cell differentiation or regeneration processes. In this review, we report and analyze the different solutions proposed in literature, for the reconstruction of tendon, muscle, and the myotendinous junction. They classically rely on the three pillars of tissue engineering, i.e., cells, biomaterials and environment (both chemical and physical stimuli). We have chosen to present biomimetic or bioinspired strategies based on understanding of the native tissue structure/functions/properties of the tissue of interest. For each tissue, we sorted the relevant publications according to an increasing degree of complexity in the materials’ shape or manufacture. We present their biological and mechanical performances, observed in vitro and in vivo when available. Although there is no consensus for a gold standard technique to reconstruct these musculo-skeletal tissues, the reader can find different ways to progress in the field and to understand the recent history in the choice of materials, from collagen to polymer-based matrices.
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38
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Peviani SM, Guzzoni V, Pinheiro-Dardis CM, Silva YPD, Fioravante ACR, Sagawa AH, Delfino GB, Durigan JLQ, Salvini TF. Regulation of extracellular matrix elements and sarcomerogenesis in response to different periods of passive stretching in the soleus muscle of rats. Sci Rep 2018; 8:9010. [PMID: 29899346 PMCID: PMC5998085 DOI: 10.1038/s41598-018-27239-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 05/21/2018] [Indexed: 01/02/2023] Open
Abstract
Stretching is a common method used to prevent muscle shortening and improve limited mobility. However, the effect of different time periods on stretching-induced adaptation of the extracellular matrix and its regulatory elements have yet to be investigated. We aimed to evaluate the expression of fibrillar collagens, sarcomerogenesis, metalloproteinase (MMP) activity and gene expression of the extracellular matrix (ECM) regulators in the soleus (SOL) muscle of rats submitted to different stretching periods. The soleus muscles were submitted to 10 sets of passive stretching over 10 (St 10d) or 15 days (St 15d) (1 min per set, with 30 seconds' rest between sets). Sarcomerogenesis, muscle cross-sectional area (CSA), and MMP activity and mRNA levels in collagen (type I, III and IV), connective tissue growth factor (CTGF), growth factor-beta (TGF-β), and lysyl oxidase (LOX) were analyzed. Passive stretching over both time periods mitigated COL-I deposition in the SOL muscle of rats. Paradoxically, 10 days of passive stretching induced COL-I and COL-III synthesis, with concomitant upregulation of TGF-β1 and CTGF at a transcriptional level. These responses may be associated with lower LOX mRNA levels in SOL muscles submitted to 10 passive stretching sessions. Moreover, sarcomerogenesis was observed after 15 days of stretching, suggesting that stretching-induced muscle adaptations are time-dependent responses.
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Affiliation(s)
- Sabrina M Peviani
- Department of Physical Therapy, São Carlos Federal University, São Carlos, São Paulo State, Brazil.
| | - Vinicius Guzzoni
- Postdoctoral Fellowship, University of Brasília, Brasília, Federal District, Brazil
| | - Clara M Pinheiro-Dardis
- Department of Physical Therapy, São Carlos Federal University, São Carlos, São Paulo State, Brazil
| | - Yara P da Silva
- Department of Physical Therapy, São Carlos Federal University, São Carlos, São Paulo State, Brazil
| | - Alisson C R Fioravante
- Department of Physical Therapy, São Carlos Federal University, São Carlos, São Paulo State, Brazil
| | - Adriana H Sagawa
- Department of Physical Therapy, São Carlos Federal University, São Carlos, São Paulo State, Brazil
| | - Gabriel B Delfino
- Department of Physical Therapy, São Carlos Federal University, São Carlos, São Paulo State, Brazil
| | - João L Q Durigan
- Graduate Program in Rehabilitation Sciences, University of Brasilia, Brasília, Federal District, Brazil
| | - Tania F Salvini
- Department of Physical Therapy, São Carlos Federal University, São Carlos, São Paulo State, Brazil
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39
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Borges MO, Medeiros DM, Minotto BB, Lima CS. Comparison between static stretching and proprioceptive neuromuscular facilitation on hamstring flexibility: systematic review and meta-analysis. EUROPEAN JOURNAL OF PHYSIOTHERAPY 2017. [DOI: 10.1080/21679169.2017.1347708] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Mariana Oliveira Borges
- Exercise Laboratory Research, School of Physical Education, Physiotherapy, and Dance, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Diulian Muniz Medeiros
- Exercise Laboratory Research, School of Physical Education, Physiotherapy, and Dance, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Bruna Borba Minotto
- Exercise Laboratory Research, School of Physical Education, Physiotherapy, and Dance, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Cláudia Silveira Lima
- Exercise Laboratory Research, School of Physical Education, Physiotherapy, and Dance, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
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40
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Medeiros DM, Lima CS. Influence of chronic stretching on muscle performance: Systematic review. Hum Mov Sci 2017; 54:220-229. [PMID: 28527424 DOI: 10.1016/j.humov.2017.05.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 05/06/2017] [Accepted: 05/10/2017] [Indexed: 10/19/2022]
Abstract
The aim of the current study was to investigate the influence of chronic stretching on muscle performance (MP) by a systematic review. The search strategy included MEDLINE, PEDro, Cochrane CENTRAL, LILACS, and manual search from inception to June 2016. Randomized and controlled clinical trials, non-randomized, and single group studies that have analyzed the influence of flexibility training (FT) (using any stretching technique) on MP were included. Differently, studies with special populations (children, elderly, and people with any dysfunction/disease), and articles that have used FT protocols shorter than three weeks or 12 sessions were excluded. The MP assessment could have been performed by functional tests (e.g. jump, sprint, stretch-shortening cycle tasks), isometric contractions, and/or isotonic contractions. Twenty-eight studies were included out of 513. Seven studies evaluated MP by stretch-shortening cycle tasks, Ten studies evaluated MP by isometric contractions, and 13 studies assessed MP by isotonic contractions. We were unable to perform a meta-analysis due to the high heterogeneity among the included studies. In an individual study level analysis, we identified that 14 studies found positive effects of chronic stretching on MP. The improvements were observed only in functional tests and isotonic contractions, isometric contractions were not affected by FT. Therefore, FT might have an influence on dynamic MP. However, more studies are necessary to confirm whether FT can positively affect MP.
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Affiliation(s)
- D M Medeiros
- Exercise Laboratory Research, School of Physical Education, Physiotherapy, and Dance, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | - C S Lima
- Exercise Laboratory Research, School of Physical Education, Physiotherapy, and Dance, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
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41
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de Rooij R, Miller KE, Kuhl E. Modeling molecular mechanisms in the axon. COMPUTATIONAL MECHANICS 2017; 59:523-537. [PMID: 28603326 PMCID: PMC5464742 DOI: 10.1007/s00466-016-1359-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Axons are living systems that display highly dynamic changes in stiffness, viscosity, and internal stress. However, the mechanistic origin of these phenomenological properties remains elusive. Here we establish a computational mechanics model that interprets cellular-level characteristics as emergent properties from molecular-level events. We create an axon model of discrete microtubules, which are connected to neighboring microtubules via discrete crosslinking mechanisms that obey a set of simple rules. We explore two types of mechanisms: passive and active crosslinking. Our passive and active simulations suggest that the stiffness and viscosity of the axon increase linearly with the crosslink density, and that both are highly sensitive to the crosslink detachment and reattachment times. Our model explains how active crosslinking with dynein motors generates internal stresses and actively drives axon elongation. We anticipate that our model will allow us to probe a wide variety of molecular phenomena-both in isolation and in interaction-to explore emergent cellular-level features under physiological and pathological conditions.
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Affiliation(s)
- R de Rooij
- Departments of Mechanical Engineering and Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - K E Miller
- Department of Integrative Biology, Michigan State University, East Lansing, MI 48824, USA
| | - E Kuhl
- Departments of Mechanical Engineering and Bioengineering, Stanford University, Stanford, CA 94305, USA
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42
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Cyron CJ, Humphrey JD. Growth and Remodeling of Load-Bearing Biological Soft Tissues. MECCANICA 2017; 52:645-664. [PMID: 28286348 PMCID: PMC5342900 DOI: 10.1007/s11012-016-0472-5] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The past two decades reveal a growing role of continuum biomechanics in understanding homeostasis, adaptation, and disease progression in soft tissues. In this paper, we briefly review the two primary theoretical approaches for describing mechano-regulated soft tissue growth and remodeling on the continuum level as well as hybrid approaches that attempt to combine the advantages of these two approaches while avoiding their disadvantages. We also discuss emerging concepts, including that of mechanobiological stability. Moreover, to motivate and put into context the different theoretical approaches, we briefly review findings from mechanobiology that show the importance of mass turnover and the prestressing of both extant and new extracellular matrix in most cases of growth and remodeling. For illustrative purposes, these concepts and findings are discussed, in large part, within the context of two load-bearing, collagen dominated soft tissues - tendons/ligaments and blood vessels. We conclude by emphasizing further examples, needs, and opportunities in this exciting field of modeling soft tissues.
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Affiliation(s)
- C J Cyron
- Institute for Computational Mechanics, Technische Universität München, Garching, Germany
| | - J D Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA; Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, CT, USA
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43
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Homogenized constrained mixture models for anisotropic volumetric growth and remodeling. Biomech Model Mechanobiol 2016; 16:889-906. [DOI: 10.1007/s10237-016-0859-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 11/18/2016] [Indexed: 10/20/2022]
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44
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Martin KS, Virgilio KM, Peirce SM, Blemker SS. Computational Modeling of Muscle Regeneration and Adaptation to Advance Muscle Tissue Regeneration Strategies. Cells Tissues Organs 2016; 202:250-266. [DOI: 10.1159/000443635] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2015] [Indexed: 11/19/2022] Open
Abstract
Skeletal muscle has an exceptional ability to regenerate and adapt following injury. Tissue engineering approaches (e.g. cell therapy, scaffolds, and pharmaceutics) aimed at enhancing or promoting muscle regeneration from severe injuries are a promising and active field of research. Computational models are beginning to advance the field by providing insight into regeneration mechanisms and therapies. In this paper, we summarize the contributions computational models have made to understanding muscle remodeling and the functional implications thereof. Next, we describe a new agent-based computational model of skeletal muscle inflammation and regeneration following acute muscle injury. Our computational model simulates the recruitment and cellular behaviors of key inflammatory cells (e.g. neutrophils and M1 and M2 macrophages) and their interactions with native muscle cells (muscle fibers, satellite stem cells, and fibroblasts) that result in the clearance of necrotic tissue and muscle fiber regeneration. We demonstrate the ability of the model to track key regeneration metrics during both unencumbered regeneration and in the case of impaired macrophage function. We also use the model to simulate regeneration enhancement when muscle is primed with inflammatory cells prior to injury, which is a putative therapeutic intervention that has not yet been investigated experimentally. Computational modeling of muscle regeneration, pursued in combination with experimental analyses, provides a quantitative framework for evaluating and predicting muscle regeneration and enables the rational design of therapeutic strategies for muscle recovery.
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45
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Armstrong MH, Buganza Tepole A, Kuhl E, Simon BR, Vande Geest JP. A Finite Element Model for Mixed Porohyperelasticity with Transport, Swelling, and Growth. PLoS One 2016; 11:e0152806. [PMID: 27078495 PMCID: PMC4831841 DOI: 10.1371/journal.pone.0152806] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 03/18/2016] [Indexed: 01/07/2023] Open
Abstract
The purpose of this manuscript is to establish a unified theory of porohyperelasticity with transport and growth and to demonstrate the capability of this theory using a finite element model developed in MATLAB. We combine the theories of volumetric growth and mixed porohyperelasticity with transport and swelling (MPHETS) to derive a new method that models growth of biological soft tissues. The conservation equations and constitutive equations are developed for both solid-only growth and solid/fluid growth. An axisymmetric finite element framework is introduced for the new theory of growing MPHETS (GMPHETS). To illustrate the capabilities of this model, several example finite element test problems are considered using model geometry and material parameters based on experimental data from a porcine coronary artery. Multiple growth laws are considered, including time-driven, concentration-driven, and stress-driven growth. Time-driven growth is compared against an exact analytical solution to validate the model. For concentration-dependent growth, changing the diffusivity (representing a change in drug) fundamentally changes growth behavior. We further demonstrate that for stress-dependent, solid-only growth of an artery, growth of an MPHETS model results in a more uniform hoop stress than growth in a hyperelastic model for the same amount of growth time using the same growth law. This may have implications in the context of developing residual stresses in soft tissues under intraluminal pressure. To our knowledge, this manuscript provides the first full description of an MPHETS model with growth. The developed computational framework can be used in concert with novel in-vitro and in-vivo experimental approaches to identify the governing growth laws for various soft tissues.
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Affiliation(s)
- Michelle Hine Armstrong
- Graduate Interdisciplinary Program in Applied Mathematics, The University of Arizona, Tucson, AZ, United States of America
| | - Adrián Buganza Tepole
- Department of Mechanical Engineering, Stanford University, Stanford, CA, United States of America
| | - Ellen Kuhl
- Department of Mechanical Engineering, Stanford University, Stanford, CA, United States of America
| | - Bruce R Simon
- Department of Aerospace and Mechanical Engineering, The University of Arizona, Tucson, AZ, United States of America
| | - Jonathan P Vande Geest
- Graduate Interdisciplinary Program in Applied Mathematics, The University of Arizona, Tucson, AZ, United States of America.,Department of Aerospace and Mechanical Engineering, The University of Arizona, Tucson, AZ, United States of America.,Graduate Interdisciplinary Program of Biomedical Engineering, The University of Arizona, Tucson, AZ, United States of America.,BIO5 Institute for Biocollaborative Research, The University of Arizona, Tucson, AZ 85721, United States of America.,Department of Biomedical Engineering, The University of Arizona, Tucson, AZ 85721, United States of America.,Department of Bioengineering, The University of Pittsburgh, Pittsburgh, PA 15219, United States of America
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46
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Moreno-Hay I, Okeson JP. Does altering the occlusal vertical dimension produce temporomandibular disorders? A literature review. J Oral Rehabil 2015; 42:875-82. [PMID: 26140528 DOI: 10.1111/joor.12326] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/31/2015] [Indexed: 11/27/2022]
Abstract
The purpose of this review was to present a comprehensive review of the scientific evidence available in the literature regarding the effect of altering the occlusal vertical dimens-ion (OVD) on producing temporomandibular disorders. The authors conducted a PubMed search with the following search terms 'temporoman-dibular disorders', 'occlusal vertical dimension', 'stomatognatic system', 'masticatory muscles' and 'skeletal muscle'. Bibliographies of all retrieved articles were consulted for additional publications. Hand-searched publications from 1938 were included. The literature review revealed a lack of well-designed studies. Traditional beliefs have been based on case reports and anecdotal opinions rather than on well-controlled clinical trials. The available evidence is weak and seems to indicate that the stomatognathic system has the ability to adapt rapidly to moderate changes in occlusal vertical dimension (OVD). Nevertheless, it should be taken into consideration that in some patients mild transient symptoms may occur, but they are most often self-limiting and without major consequence. In conclusion, there is no indication that permanent alteration in the OVD will produce long-lasting TMD symptoms. However, additional studies are needed.
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Affiliation(s)
- I Moreno-Hay
- Orofacial Pain Center, College of Dentistry, University of Kentucky, Lexington, KY, USA
| | - J P Okeson
- Orofacial Pain Center, College of Dentistry, University of Kentucky, Lexington, KY, USA
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47
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Emerging Brain Morphologies from Axonal Elongation. Ann Biomed Eng 2015; 43:1640-53. [PMID: 25824370 DOI: 10.1007/s10439-015-1312-9] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 03/23/2015] [Indexed: 12/13/2022]
Abstract
Understanding the characteristic morphology of our brain remains a challenging, yet important task in human evolution, developmental biology, and neurosciences. Mathematical modeling shapes our understanding of cortical folding and provides functional relations between cortical wavelength, thickness, and stiffness. Yet, current mathematical models are phenomenologically isotropic and typically predict non-physiological, periodic folding patterns. Here we establish a mechanistic model for cortical folding, in which macroscopic changes in white matter volume are a natural consequence of microscopic axonal growth. To calibrate our model, we consult axon elongation experiments in chick sensory neurons. We demonstrate that a single parameter, the axonal growth rate, explains a wide variety of in vitro conditions including immediate axonal thinning and gradual thickness restoration. We embed our axonal growth model into a continuum model for brain development using axonal orientation distributions motivated by diffusion spectrum imaging. Our simulations suggest that white matter anisotropy-as an emergent property from directional axonal growth-intrinsically induces symmetry breaking, and predicts more physiological, less regular morphologies with regionally varying gyral wavelengths and sulcal depths. Mechanistic modeling of brain development could establish valuable relationships between brain connectivity, brain anatomy, and brain function.
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48
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An G. Integrating physiology across scales and formalizing hypothesis exploration with agent-based modeling. J Appl Physiol (1985) 2015; 118:1191-2. [PMID: 25814637 DOI: 10.1152/japplphysiol.00243.2015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Gary An
- University of Chicago, Surgery, Chicago, Illinois
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49
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Martin KS, Blemker SS, Peirce SM. Agent-based computational model investigates muscle-specific responses to disuse-induced atrophy. J Appl Physiol (1985) 2015; 118:1299-309. [PMID: 25722379 DOI: 10.1152/japplphysiol.01150.2014] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 02/20/2015] [Indexed: 01/27/2023] Open
Abstract
Skeletal muscle is highly responsive to use. In particular, muscle atrophy attributable to decreased activity is a common problem among the elderly and injured/immobile. However, each muscle does not respond the same way. We developed an agent-based model that generates a tissue-level skeletal muscle response to disuse/immobilization. The model incorporates tissue-specific muscle fiber architecture parameters and simulates changes in muscle fiber size as a result of disuse-induced atrophy that are consistent with published experiments. We created simulations of 49 forelimb and hindlimb muscles of the rat by incorporating eight fiber-type and size parameters to explore how these parameters, which vary widely across muscles, influence sensitivity to disuse-induced atrophy. Of the 49 muscles modeled, the soleus exhibited the greatest atrophy after 14 days of simulated immobilization (51% decrease in fiber size), whereas the extensor digitorum communis atrophied the least (32%). Analysis of these simulations revealed that both fiber-type distribution and fiber-size distribution influence the sensitivity to disuse atrophy even though no single tissue architecture parameter correlated with atrophy rate. Additionally, software agents representing fibroblasts were incorporated into the model to investigate cellular interactions during atrophy. Sensitivity analyses revealed that fibroblast agents have the potential to affect disuse-induced atrophy, albeit with a lesser effect than fiber type and size. In particular, muscle atrophy elevated slightly with increased initial fibroblast population and increased production of TNF-α. Overall, the agent-based model provides a novel framework for investigating both tissue adaptations and cellular interactions in skeletal muscle during atrophy.
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Affiliation(s)
- Kyle S Martin
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Silvia S Blemker
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia; Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia; Department of Orthopaedic Surgery, University of Virginia, Charlottesville, Virginia;
| | - Shayn M Peirce
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia; Department of Ophthalmology, University of Virginia, Charlottesville, Virginia; Department of Plastic Surgery, University of Virginia, Charlottesville, Virginia
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50
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Huijing PA, Maas H. Adaptation of physiological cross-sectional area and serial number of sarcomeres after tendon transfer of rat muscle. Scand J Med Sci Sports 2015; 26:244-55. [PMID: 25693427 DOI: 10.1111/sms.12431] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2015] [Indexed: 12/24/2022]
Abstract
Tendon transfer surgery to a new extensor insertion was performed for musculus flexor carpi ulnaris (FCU) of young adult rats, after which animals were allowed to recover. Mechanical properties and adaptive effects on body mass, bone growth, serial number of sarcomeres, and muscle physiological cross-sectional area were studied. Between the transfer and control groups, no differences were found for body mass and forearm length growth. In contrast, transferred muscles had a 19% smaller physiological cross-sectional area and 25% fewer sarcomeres in series within its muscle fibers than control muscles, i.e., a deficit in muscle belly growth is present. Our present results confirm our the length of previous work showing a limited capability of changing the adapted transferred FCU muscle belly, as the muscle-tendon complex is stretched, so that most of the acute FCU length change must originate from the tendon. This should most likely be attributed to surgery-related additional and/or altered connective tissue linkages at the muscle-tendon boundary. The substantially increased FCU tendon length found, after recovery from surgery and adaptation to the conditions of the transferred position, is likely to be related to such enhanced stretching of the FCU tendon.
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Affiliation(s)
- P A Huijing
- MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, Amsterdam, The Netherlands
| | - H Maas
- MOVE Research Institute Amsterdam, Faculty of Human Movement Sciences, VU University Amsterdam, Amsterdam, The Netherlands
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