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Millward DJ. Post-natal muscle growth and protein turnover: a narrative review of current understanding. Nutr Res Rev 2024; 37:141-168. [PMID: 37395180 DOI: 10.1017/s0954422423000124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
A model explaining the dietary-protein-driven post-natal skeletal muscle growth and protein turnover in the rat is updated, and the mechanisms involved are described, in this narrative review. Dietary protein controls both bone length and muscle growth, which are interrelated through mechanotransduction mechanisms with muscle growth induced both from stretching subsequent to bone length growth and from internal work against gravity. This induces satellite cell activation, myogenesis and remodelling of the extracellular matrix, establishing a growth capacity for myofibre length and cross-sectional area. Protein deposition within this capacity is enabled by adequate dietary protein and other key nutrients. After briefly reviewing the experimental animal origins of the growth model, key concepts and processes important for growth are reviewed. These include the growth in number and size of the myonuclear domain, satellite cell activity during post-natal development and the autocrine/paracrine action of IGF-1. Regulatory and signalling pathways reviewed include developmental mechanotransduction, signalling through the insulin/IGF-1-PI3K-Akt and the Ras-MAPK pathways in the myofibre and during mechanotransduction of satellite cells. Likely pathways activated by maximal-intensity muscle contractions are highlighted and the regulation of the capacity for protein synthesis in terms of ribosome assembly and the translational regulation of 5-TOPmRNA classes by mTORC1 and LARP1 are discussed. Evidence for and potential mechanisms by which volume limitation of muscle growth can occur which would limit protein deposition within the myofibre are reviewed. An understanding of how muscle growth is achieved allows better nutritional management of its growth in health and disease.
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Affiliation(s)
- D Joe Millward
- Department of Nutritional Sciences, School of Biosciences & Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
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2
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Josvai M, Polyak E, Kalluri M, Robertson S, Crone WC, Suzuki M. An engineered in vitro model of the human myotendinous junction. Acta Biomater 2024; 180:279-294. [PMID: 38604466 PMCID: PMC11088524 DOI: 10.1016/j.actbio.2024.04.007] [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: 11/21/2023] [Revised: 03/12/2024] [Accepted: 04/03/2024] [Indexed: 04/13/2024]
Abstract
The myotendinous junction (MTJ) is a vulnerable region at the interface of skeletal muscle and tendon that forms an integrated mechanical unit. This study presents a technique for the spatially restrictive co-culture of human embryonic stem cell (hESC)-derived skeletal myocytes and primary tenocytes for two-dimensional modeling of the MTJ. Micropatterned lanes of extracellular matrix and a 2-well culture chamber define the initial regions of occupation. On day 1, both lines occupy less than 20 % of the initially vacant interstitial zone, referred to henceforth as the junction. Myocyte-tenocyte interdigitations are observed by day 7. Immunocytochemistry reveals enhanced organization and alignment of patterned myocyte and tenocyte features, as well as differential expression of multiple MTJ markers. On day 24, electrically stimulated junction myocytes demonstrate negative contractile strains, while positive tensile strains are exhibited by mechanically passive tenocytes at the junction. Unpatterned tenocytes distal to the junction experience significantly decreased strains in comparison to cells at the interface. Unpatterned myocytes have impaired organization and uncoordinated contractile behavior. These findings suggest that this platform is capable of inducing myocyte-tenocyte junction formation and mechanical coupling similar to the native MTJ, showing transduction of force across the cell-cell interface. STATEMENT OF SIGNIFICANCE: The myotendinous junction (MTJ) is an integrated structure that transduces force across the muscle-tendon boundary, making the region vulnerable to strain injury. Despite the clinical relevance, previous in vitro models of the MTJ lack the structure and mechanical accuracy of the native tissue and have difficulty transmitting force across the cell-cell interface. This study demonstrates an in vitro model of the MTJ, using spatially restrictive cues to inform human myocyte-tenocyte interactions and architecture. The model expressed MTJ markers and developed anisotropic myocyte-tenocyte integrations that resemble the native tissue and allow for force transduction from contracting myocytes to passive tenocyte regions. As such, this study presents a system capable of investigating development, injury, and pathology in the human MTJ.
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Affiliation(s)
- Mitchell Josvai
- Department of Biomedical Engineering, University of Wisconsin-Madison, Engineering Centers Building, 2126, 1550 Engineering Dr, Madison WI 53706, USA; Wisconsin Institute for Discovery, University of Wisconsin-Madison, 330 N Orchard St, Madison, WI 53715, USA
| | - Erzsebet Polyak
- Department of Comparative Biosciences, University of Wisconsin-Madison, Veterinary Medicine Bldg, 2015 Linden Dr, Madison, WI 53706, USA
| | - Meghana Kalluri
- Department of Biomedical Engineering, University of Wisconsin-Madison, Engineering Centers Building, 2126, 1550 Engineering Dr, Madison WI 53706, USA; Wisconsin Institute for Discovery, University of Wisconsin-Madison, 330 N Orchard St, Madison, WI 53715, USA
| | - Samantha Robertson
- Department of Comparative Biosciences, University of Wisconsin-Madison, Veterinary Medicine Bldg, 2015 Linden Dr, Madison, WI 53706, USA
| | - Wendy C Crone
- Department of Biomedical Engineering, University of Wisconsin-Madison, Engineering Centers Building, 2126, 1550 Engineering Dr, Madison WI 53706, USA; Wisconsin Institute for Discovery, University of Wisconsin-Madison, 330 N Orchard St, Madison, WI 53715, USA; The Stem Cell and Regenerative Medicine Center, University of Wisconsin-Madison, 1111 Highland Ave, Madison, WI 53705, USA; Department of Nuclear Engineering and Engineering Physics, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, WI 53706, USA; Department of Mechanical Engineering, University of Wisconsin-Madison, 1513 University Avenue, Madison, WI 53706, USA.
| | - Masatoshi Suzuki
- Department of Biomedical Engineering, University of Wisconsin-Madison, Engineering Centers Building, 2126, 1550 Engineering Dr, Madison WI 53706, USA; Department of Comparative Biosciences, University of Wisconsin-Madison, Veterinary Medicine Bldg, 2015 Linden Dr, Madison, WI 53706, USA; The Stem Cell and Regenerative Medicine Center, University of Wisconsin-Madison, 1111 Highland Ave, Madison, WI 53705, USA.
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3
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Libardi CA, Godwin JS, Reece TM, Ugrinowitsch C, Herda TJ, Roberts MD. Effects of low-load resistance training with blood flow restriction on muscle fiber myofibrillar and extracellular area. Front Physiol 2024; 15:1368646. [PMID: 38444764 PMCID: PMC10912282 DOI: 10.3389/fphys.2024.1368646] [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: 01/11/2024] [Accepted: 02/05/2024] [Indexed: 03/07/2024] Open
Abstract
Blood flow restriction applied during low-load resistance training (LL-BFR) induces a similar increase in the cross-sectional area of muscle fibers (fCSA) compared to traditional high-load resistance training (HL-RT). However, it is unclear whether LL-BFR leads to differential changes in myofibrillar spacing in muscle fibers and/or extracellular area compared to HL-RT. Therefore, this study aimed to investigate whether the hypertrophy of type I and II fibers induced by LL-BFR or HL-RT is accompanied by differential changes in myofibrillar and non-myofibrillar areas. In addition, we examined if extracellular spacing was differentially affected between these two training protocols. Twenty recreationally active participants were assigned to LL-BFR or HL-RT groups and underwent a 6-week training program. Muscle biopsies were taken before and after the training period. The fCSA of type I and II fibers, the area occupied by myofibrillar and non-myofibrillar components, and extracellular spacing were analyzed using immunohistochemistry techniques. Despite the significant increase in type II and mean (type I + II) fCSA (p < 0.05), there were no significant changes in the proportionality of the myofibrillar and non-myofibrillar areas [∼86% and ∼14%, respectively (p > 0.05)], indicating that initial adaptations to LL-BFR are primarily characterized by conventional hypertrophy rather than disproportionate non-myofibrillar expansion. Additionally, extracellular spacing was not significantly altered between protocols. In summary, our study reveals that LL-BFR, like HL-RT, induces skeletal muscle hypertrophy with proportional changes in the areas occupied by myofibrillar, non-myofibrillar, and extracellular components.
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Affiliation(s)
- Cleiton A. Libardi
- MUSCULAB–Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of Sao Carlos, Sao Carlos, Brazil
| | - Joshua S. Godwin
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Tanner M. Reece
- Program in Physical Therapy, Washington University School of Medicine, St. Louis, MO, United States
| | - Carlos Ugrinowitsch
- School of Physical Education and Sport, University of Sao Paulo, Sao Paulo, Brazil
- Department of Health Sciences and Human Performance, The University of Tampa, Tampa, FL, United States
| | - Trent J. Herda
- Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, KS, United States
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4
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Di Leo V, Bernardino Gomes TM, Vincent AE. Interactions of mitochondrial and skeletal muscle biology in mitochondrial myopathy. Biochem J 2023; 480:1767-1789. [PMID: 37965929 PMCID: PMC10657187 DOI: 10.1042/bcj20220233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 10/24/2023] [Accepted: 10/26/2023] [Indexed: 11/16/2023]
Abstract
Mitochondrial dysfunction in skeletal muscle fibres occurs with both healthy aging and a range of neuromuscular diseases. The impact of mitochondrial dysfunction in skeletal muscle and the way muscle fibres adapt to this dysfunction is important to understand disease mechanisms and to develop therapeutic interventions. Furthermore, interactions between mitochondrial dysfunction and skeletal muscle biology, in mitochondrial myopathy, likely have important implications for normal muscle function and physiology. In this review, we will try to give an overview of what is known to date about these interactions including metabolic remodelling, mitochondrial morphology, mitochondrial turnover, cellular processes and muscle cell structure and function. Each of these topics is at a different stage of understanding, with some being well researched and understood, and others in their infancy. Furthermore, some of what we know comes from disease models. Whilst some findings are confirmed in humans, where this is not yet the case, we must be cautious in interpreting findings in the context of human muscle and disease. Here, our goal is to discuss what is known, highlight what is unknown and give a perspective on the future direction of research in this area.
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Affiliation(s)
- Valeria Di Leo
- Wellcome Centre for Mitochondrial Research, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle NE2 4HH, U.K
- NIHR Newcastle Biomedical Research Centre, Biomedical Research Building, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, U.K
| | - Tiago M. Bernardino Gomes
- Wellcome Centre for Mitochondrial Research, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle NE2 4HH, U.K
- NIHR Newcastle Biomedical Research Centre, Biomedical Research Building, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, U.K
- NHS Highly Specialised Service for Rare Mitochondrial Disorders, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE2 4HH, U.K
| | - Amy E. Vincent
- Wellcome Centre for Mitochondrial Research, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle NE2 4HH, U.K
- NIHR Newcastle Biomedical Research Centre, Biomedical Research Building, Campus for Ageing and Vitality, Newcastle upon Tyne NE4 5PL, U.K
- John Walton Muscular Dystrophy Research Centre, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle NE2 4HH, U.K
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5
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Balderas-Villalobos J, Medina-Contreras JML, Lynch C, Kabadi R, Hayles J, Ramirez RJ, Tan AY, Kaszala K, Samsó M, Huizar JF, Eltit JM. Mechanisms of adaptive hypertrophic cardiac remodeling in a large animal model of premature ventricular contraction-induced cardiomyopathy. IUBMB Life 2023; 75:926-940. [PMID: 37427864 PMCID: PMC10592397 DOI: 10.1002/iub.2765] [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: 03/05/2023] [Accepted: 06/13/2023] [Indexed: 07/11/2023]
Abstract
Frequent premature ventricular contractions (PVCs) promoted eccentric cardiac hypertrophy and reduced ejection fraction (EF) in a large animal model of PVC-induced cardiomyopathy (PVC-CM), but the molecular mechanisms and markers of this hypertrophic remodeling remain unexplored. Healthy mongrel canines were implanted with pacemakers to deliver bigeminal PVCs (50% burden with 200-220 ms coupling interval). After 12 weeks, left ventricular (LV) free wall samples were studied from PVC-CM and Sham groups. In addition to reduced LV ejection fraction (LVEF), the PVC-CM group showed larger cardiac myocytes without evident ultrastructural alterations compared to the Sham group. Biochemical markers of pathological hypertrophy, such as store-operated Ca2+ entry, calcineurin/NFAT pathway, β-myosin heavy chain, and skeletal type α-actin were unaltered in the PVC-CM group. In contrast, pro-hypertrophic and antiapoptotic pathways including ERK1/2 and AKT/mTOR were activated and/or overexpressed in the PVC-CM group, which appeared counterbalanced by an overexpression of protein phosphatase 1 and a borderline elevation of the anti-hypertrophic factor atrial natriuretic peptide. Moreover, the potent angiogenic and pro-hypertrophic factor VEGF-A and its receptor VEGFR2 were significantly elevated in the PVC-CM group. In conclusion, a molecular program is in place to keep this structural remodeling associated with frequent PVCs as an adaptive pathological hypertrophy.
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Affiliation(s)
| | - JML Medina-Contreras
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University
| | - Christopher Lynch
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University
| | - Rajiv Kabadi
- Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, United States of America
| | - Janée Hayles
- Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, United States of America
| | - Rafael J. Ramirez
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University
| | - Alex Y. Tan
- Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, United States of America
- Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA, United States of America
| | - Karoly Kaszala
- Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, United States of America
- Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA, United States of America
| | - Montserrat Samsó
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University
| | - Jose F. Huizar
- Pauley Heart Center, Virginia Commonwealth University, Richmond, VA, United States of America
- Hunter Holmes McGuire Veterans Affairs Medical Center, Richmond, VA, United States of America
| | - Jose M. Eltit
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University
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Roberts MD, McCarthy JJ, Hornberger TA, Phillips SM, Mackey AL, Nader GA, Boppart MD, Kavazis AN, Reidy PT, Ogasawara R, Libardi CA, Ugrinowitsch C, Booth FW, Esser KA. Mechanisms of mechanical overload-induced skeletal muscle hypertrophy: current understanding and future directions. Physiol Rev 2023; 103:2679-2757. [PMID: 37382939 PMCID: PMC10625844 DOI: 10.1152/physrev.00039.2022] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 06/12/2023] [Accepted: 06/21/2023] [Indexed: 06/30/2023] Open
Abstract
Mechanisms underlying mechanical overload-induced skeletal muscle hypertrophy have been extensively researched since the landmark report by Morpurgo (1897) of "work-induced hypertrophy" in dogs that were treadmill trained. Much of the preclinical rodent and human resistance training research to date supports that involved mechanisms include enhanced mammalian/mechanistic target of rapamycin complex 1 (mTORC1) signaling, an expansion in translational capacity through ribosome biogenesis, increased satellite cell abundance and myonuclear accretion, and postexercise elevations in muscle protein synthesis rates. However, several lines of past and emerging evidence suggest that additional mechanisms that feed into or are independent of these processes are also involved. This review first provides a historical account of how mechanistic research into skeletal muscle hypertrophy has progressed. A comprehensive list of mechanisms associated with skeletal muscle hypertrophy is then outlined, and areas of disagreement involving these mechanisms are presented. Finally, future research directions involving many of the discussed mechanisms are proposed.
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Affiliation(s)
- Michael D Roberts
- School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - John J McCarthy
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, United States
| | - Troy A Hornberger
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Stuart M Phillips
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Abigail L Mackey
- Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital-Bispebjerg and Frederiksberg, and Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Gustavo A Nader
- Department of Kinesiology and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania, United States
| | - Marni D Boppart
- Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States
| | - Andreas N Kavazis
- School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - Paul T Reidy
- Department of Kinesiology, Nutrition and Health, Miami University, Oxford, Ohio, United States
| | - Riki Ogasawara
- Healthy Food Science Research Group, Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Cleiton A Libardi
- MUSCULAB-Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos, São Carlos, Brazil
| | - Carlos Ugrinowitsch
- School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Frank W Booth
- Department of Biomedical Sciences, University of Missouri, Columbia, Missouri, United States
| | - Karyn A Esser
- Department of Physiology and Aging, College of Medicine, University of Florida, Gainesville, Florida, United States
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7
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Smith JAB, Murach KA, Dyar KA, Zierath JR. Exercise metabolism and adaptation in skeletal muscle. Nat Rev Mol Cell Biol 2023; 24:607-632. [PMID: 37225892 PMCID: PMC10527431 DOI: 10.1038/s41580-023-00606-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/30/2023] [Indexed: 05/26/2023]
Abstract
Viewing metabolism through the lens of exercise biology has proven an accessible and practical strategy to gain new insights into local and systemic metabolic regulation. Recent methodological developments have advanced understanding of the central role of skeletal muscle in many exercise-associated health benefits and have uncovered the molecular underpinnings driving adaptive responses to training regimens. In this Review, we provide a contemporary view of the metabolic flexibility and functional plasticity of skeletal muscle in response to exercise. First, we provide background on the macrostructure and ultrastructure of skeletal muscle fibres, highlighting the current understanding of sarcomeric networks and mitochondrial subpopulations. Next, we discuss acute exercise skeletal muscle metabolism and the signalling, transcriptional and epigenetic regulation of adaptations to exercise training. We address knowledge gaps throughout and propose future directions for the field. This Review contextualizes recent research of skeletal muscle exercise metabolism, framing further advances and translation into practice.
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Affiliation(s)
- Jonathon A B Smith
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Kevin A Murach
- Molecular Mass Regulation Laboratory, Exercise Science Research Center, Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, AR, USA
| | - Kenneth A Dyar
- Metabolic Physiology, Institute for Diabetes and Cancer, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Juleen R Zierath
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Harriot AD, Altair Morris T, Vanegas C, Kallenbach J, Pinto K, Joca HC, Moutin MJ, Shi G, Ursitti JA, Grosberg A, Ward CW. Detyrosinated microtubule arrays drive myofibrillar malformations in mdx muscle fibers. Front Cell Dev Biol 2023; 11:1209542. [PMID: 37691825 PMCID: PMC10485621 DOI: 10.3389/fcell.2023.1209542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 08/09/2023] [Indexed: 09/12/2023] Open
Abstract
Altered myofibrillar structure is a consequence of dystrophic pathology that impairs skeletal muscle contractile function and increases susceptibility to contraction injury. In murine Duchenne muscular dystrophy (mdx), myofibrillar alterations are abundant in advanced pathology (>4 months), an age where we formerly established densified microtubule (MT) arrays enriched in detyrosinated (deTyr) tubulin as negative disease modifiers impacting cell mechanics and mechanotransduction. Given the essential role of deTyr-enriched MT arrays in myofibrillar growth, maintenance, and repair, we examined the increased abundance of these arrays as a potential mechanism for these myofibrillar alterations. Here we find an increase in deTyr-tubulin as an early event in dystrophic pathology (4 weeks) with no evidence myofibrillar alterations. At 16 weeks, we show deTyr-enriched MT arrays significantly densified and co-localized to areas of myofibrillar malformation. Profiling the enzyme complexes responsible for deTyr-tubulin, we identify vasohibin 2 (VASH2) and small vasohibin binding protein (SVBP) significantly elevated in the mdx muscle at 4 weeks. Using the genetic increase in VASH2/SVBP expression in 4 weeks wild-type mice we find densified deTyr-enriched MT arrays that co-segregate with myofibrillar malformations similar to those in the 16 weeks mdx. Given that no changes in sarcomere organization were identified in fibers expressing sfGFP as a control, we conclude that disease-dependent densification of deTyr-enriched MT arrays underscores the altered myofibrillar structure in dystrophic skeletal muscle fibers.
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Affiliation(s)
- Anicca D. Harriot
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Tessa Altair Morris
- Center for Complex Biological Systems, Edwards Lifesciences Foundation Cardiovascular Innovation and Research Center, and the NSF-Simons Center for Multiscale Cell Fate Research, University of California, Irvine, Irvine, CA, United States
| | - Camilo Vanegas
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Jacob Kallenbach
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Kaylie Pinto
- Department of Molecular Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Humberto C. Joca
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Marie-Jo Moutin
- INSERM U1216 Centre National de la Recherche Scientifique, Grenoble Institut Neurosciences, University Grenoble Alpes, Grenoble, France
| | - Guoli Shi
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Jeanine A. Ursitti
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Anna Grosberg
- Center for Complex Biological Systems, Edwards Lifesciences Foundation Cardiovascular Innovation and Research Center, and the NSF-Simons Center for Multiscale Cell Fate Research, University of California, Irvine, Irvine, CA, United States
- Department of Biomedical Engineering, Sue and Bill Gross Stem Cell Research, University of California, Irvine, Irvine, CA, United States
- Department of Chemical and Biomolecular Engineering, Sue and Bill Gross Stem Cell Research, University of California, Irvine, Irvine, CA, United States
| | - Christopher W. Ward
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
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9
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Asencio A, Malingen S, Kooiker KB, Powers JD, Davis J, Daniel T, Moussavi-Harami F. Machine learning meets Monte Carlo methods for models of muscle's molecular machinery to classify mutations. J Gen Physiol 2023; 155:e202213291. [PMID: 37000171 PMCID: PMC10067704 DOI: 10.1085/jgp.202213291] [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] [Received: 10/31/2022] [Revised: 02/14/2023] [Accepted: 03/14/2023] [Indexed: 04/01/2023] Open
Abstract
The timing and magnitude of force generation by a muscle depend on complex interactions in a compliant, contractile filament lattice. Perturbations in these interactions can result in cardiac muscle diseases. In this study, we address the fundamental challenge of connecting the temporal features of cardiac twitches to underlying rate constants and their perturbations associated with genetic cardiomyopathies. Current state-of-the-art metrics for characterizing the mechanical consequence of cardiac muscle disease do not utilize information embedded in the complete time course of twitch force. We pair dimension reduction techniques and machine learning methods to classify underlying perturbations that shape the timing of twitch force. To do this, we created a large twitch dataset using a spatially explicit Monte Carlo model of muscle contraction. Uniquely, we modified the rate constants of this model in line with mouse models of cardiac muscle disease and varied mutation penetrance. Ultimately, the results of this study show that machine learning models combined with biologically informed dimension reduction techniques can yield excellent classification accuracy of underlying muscle perturbations.
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Affiliation(s)
- Anthony Asencio
- Department of Biology, University of Washington, Seattle, WA, USA
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Division of Cardiology, University of Washington, Seattle, WA, USA
- Center for Transnational Muscle Research, University of Washington, Seattle, WA, USA
| | - Sage Malingen
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Center for Transnational Muscle Research, University of Washington, Seattle, WA, USA
| | - Kristina B. Kooiker
- Division of Cardiology, University of Washington, Seattle, WA, USA
- Center for Transnational Muscle Research, University of Washington, Seattle, WA, USA
- Center for Cardiovascular Biology, University of Washington, Seattle, WA, USA
| | - Joseph D. Powers
- Department of Bioengineering, University of California, San Diego, San Diego, CA, USA
| | - Jennifer Davis
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Center for Transnational Muscle Research, University of Washington, Seattle, WA, USA
- Department of Laboratory Medicine Pathology, University of Washington, Seattle, WA, USA
- Center for Cardiovascular Biology, University of Washington, Seattle, WA, USA
| | - Thomas Daniel
- Department of Biology, University of Washington, Seattle, WA, USA
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Center for Transnational Muscle Research, University of Washington, Seattle, WA, USA
| | - Farid Moussavi-Harami
- Division of Cardiology, University of Washington, Seattle, WA, USA
- Center for Transnational Muscle Research, University of Washington, Seattle, WA, USA
- Department of Laboratory Medicine Pathology, University of Washington, Seattle, WA, USA
- Center for Cardiovascular Biology, University of Washington, Seattle, WA, USA
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10
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Lim JY, Frontera WR. Skeletal muscle aging and sarcopenia: Perspectives from mechanical studies of single permeabilized muscle fibers. J Biomech 2023; 152:111559. [PMID: 37027961 PMCID: PMC10164716 DOI: 10.1016/j.jbiomech.2023.111559] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023]
Abstract
The decline in muscle mass and strength with age is well documented and associated with weakness, decreased flexibility, vulnerability to diseases and/or injuries, and impaired functional restoration. The term sarcopenia has been used to refer to the loss of muscle mass, strength and impaired physical performance with advanced adult age and recently has become a major clinical entity in a super-aged society. To understand the pathophysiology and clinical manifestations of sarcopenia, it is essential to explore the age-related changes in the intrinsic properties of muscle fibers. Mechanical experiments with single muscle fibers have been conducted during the last 80 years and applied to human muscle research in the last 45 years as an in-vitro muscle function test. Fundamental active and passive mechanical properties of skeletal muscle can be evaluated using the isolated permeabilized (chemically skinned) single muscle fiber preparation. Changes in the intrinsic properties of older human single muscle fibers can be useful biomarkers of aging and sarcopenia. In this review, we summarize the historical development of single muscle fiber mechanical studies, the definition and diagnosis of muscle aging and sarcopenia, and age-related change of active and passive mechanical properties in single muscle fibers and discuss how these changes can be used to assess muscle aging and sarcopenia.
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Affiliation(s)
- Jae-Young Lim
- Department of Rehabilitation Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam-si Gyeonggi-do, South Korea
| | - Walter R Frontera
- Department of Physiology and Department of Physical Medicine, Rehabilitation, and Sports Medicine, University of Puerto Rico School of Medicine, San Juan, Puerto Rico.
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11
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Rusu MC, Mănoiu VS, Nicolescu MI. Pennate myofibrils of the rat temporal muscle. Ann Anat 2023; 249:152096. [PMID: 37011827 DOI: 10.1016/j.aanat.2023.152096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 03/19/2023] [Accepted: 03/21/2023] [Indexed: 04/03/2023]
Abstract
BACKGROUND The force a muscle exerts is partly determined by anatomical parameters, such as its physiological cross-section. The temporal muscle is structurally heterogeneous. To the authors' knowledge, the ultrastructure of this muscle has been poorly specifically studied. METHODS Five adult Wistar rats weighting 350-400g were used as temporal muscle donors. Tissues were specifically processed and studied under transmission electron microscope. RESULTS On ultrathin cuts, the general ultrastructural pattern of striated muscles was observed. Moreover, pennate sarcomeres were identified, sharing a one-end insertion on the same Z-disc. Bipennate morphologies resulted when two neighbor sarcomeres, attached on different neighbor Z-discs and separated at that end by a triad, converged to the same Z-disc at the opposite ends, thus building a thicker myofibril distinctively flanked by triads. Tripennate morphologies were identified when sarcomeres from three different Z-discs converged to the same Z-disc at the opposite ends. CONCLUSIONS These results support recent evidence of sarcomeres branching gathered in mice. Adequate identification of the sites of excitation-contraction coupling should be on both sides of a myofibril, on bidimensional ultrathin cuts, to avoid false positive results due to putative longitudinal folds of myofibrils.
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Affiliation(s)
- Mugurel Constantin Rusu
- Division of Anatomy, Faculty of Dentistry, "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.
| | - Vasile Sorin Mănoiu
- Department of Cellular and Molecular Biology, National Institute of Research and Development for Biological Sciences, Bucharest, Romania
| | - Mihnea Ioan Nicolescu
- Division of Histology and Regenerative Dentistry, Faculty of Dentistry, "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania; Radiobiology Laboratory, "Victor Babeș" National Institute of Pathology, Bucharest, Romania
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12
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Fan X, Zheng X, An T, Li X, Leung N, Zhu B, Sui T, Shi N, Fan T, Zhao Q. Light diffraction by sarcomeres produces iridescence in transmission in the transparent ghost catfish. Proc Natl Acad Sci U S A 2023; 120:e2219300120. [PMID: 36913569 PMCID: PMC10041080 DOI: 10.1073/pnas.2219300120] [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: 11/11/2022] [Accepted: 02/07/2023] [Indexed: 03/15/2023] Open
Abstract
Despite the elaborate varieties of iridescent colors in biological species, most of them are reflective. Here we show the rainbow-like structural colors found in the ghost catfish (Kryptopterus vitreolus), which exist only in transmission. The fish shows flickering iridescence throughout the transparent body. The iridescence originates from the collective diffraction of light after passing through the periodic band structures of the sarcomeres inside the tightly stacked myofibril sheets, and the muscle fibers thus work as transmission gratings. The length of the sarcomeres varies from ~1 μm from the body neutral plane near the skeleton to ~2 μm next to the skin, and the iridescence of a live fish mainly results from the longer sarcomeres. The length of the sarcomere changes by ~80 nm as it relaxes and contracts, and the fish shows a quickly blinking dynamic diffraction pattern as it swims. While similar diffraction colors are also observed in thin slices of muscles from non-transparent species such as the white crucian carps, a transparent skin is required indeed to have such iridescence in live species. The ghost catfish skin is of a plywood structure of collagen fibrils, which allows more than 90% of the incident light to pass directly into the muscles and the diffracted light to exit the body. Our findings could also potentially explain the iridescence in other transparent aquatic species, including the eel larvae (Leptocephalus) and the icefishes (Salangidae).
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Affiliation(s)
- Xiujun Fan
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
| | - Xuezhi Zheng
- Department of Electrical Engineering, KU Leuven, LeuvenB3001, Belgium
| | - Tong An
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
| | - Xiuhong Li
- Shanghai Synchrotron Radiation Facility, Shanghai201204, China
| | - Nathanael Leung
- School of Mechanical Engineering Sciences, University of Surrey, SurreyGU2 7XH, UK
| | - Bin Zhu
- School of Mechanical Engineering Sciences, University of Surrey, SurreyGU2 7XH, UK
| | - Tan Sui
- School of Mechanical Engineering Sciences, University of Surrey, SurreyGU2 7XH, UK
| | - Nan Shi
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
| | - Tongxiang Fan
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
| | - Qibin Zhao
- State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
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13
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Jerban S, Ma Y, Tang Q, Fu E, Szeverenyi N, Jang H, Chung CB, Du J, Chang EY. Robust Assessment of Macromolecular Fraction (MMF) in Muscle with Differing Fat Fraction Using Ultrashort Echo Time (UTE) Magnetization Transfer Modeling with Measured T1. Diagnostics (Basel) 2023; 13:876. [PMID: 36900019 PMCID: PMC10001337 DOI: 10.3390/diagnostics13050876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/17/2023] [Accepted: 02/21/2023] [Indexed: 03/03/2023] Open
Abstract
Magnetic resonance imaging (MRI) is widely regarded as the most comprehensive imaging modality to assess skeletal muscle quality and quantity. Magnetization transfer (MT) imaging can be used to estimate the fraction of water and macromolecular proton pools, with the latter including the myofibrillar proteins and collagen, which are related to the muscle quality and its ability to generate force. MT modeling combined with ultrashort echo time (UTE-MT modeling) may improve the evaluation of the myotendinous junction and regions with fibrotic tissues in the skeletal muscles, which possess short T2 values and higher bound-water concentration. The fat present in muscle has always been a source of concern in macromolecular fraction (MMF) calculation. This study aimed to investigate the impact of fat fraction (FF) on the estimated MMF in bovine skeletal muscle phantoms embedded in pure fat. MMF was calculated for several regions of interest (ROIs) with differing FFs using UTE-MT modeling with and without T1 measurement and B1 correction. Calculated MMF using measured T1 showed a robust trend, particularly with a negligible error (<3%) for FF < 20%. Around 5% MMF reduction occurred for FF > 30%. However, MMF estimation using a constant T1 was robust only for regions with FF < 10%. The MTR and T1 values were also robust for only FF < 10%. This study highlights the potential of the UTE-MT modeling with accurate T1 measurement for robust muscle assessment while remaining insensitive to fat infiltration up to moderate levels.
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Affiliation(s)
- Saeed Jerban
- Department of Radiology, University of California, La Jolla, San Diego, CA 92093, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
- Department of Orthopedic Surgery, University of California, La Jolla, San Diego, CA 92093, USA
| | - Yajun Ma
- Department of Radiology, University of California, La Jolla, San Diego, CA 92093, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
| | - Qingbo Tang
- Department of Radiology, University of California, La Jolla, San Diego, CA 92093, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
| | - Eddie Fu
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
| | - Nikolaus Szeverenyi
- Department of Radiology, University of California, La Jolla, San Diego, CA 92093, USA
| | - Hyungseok Jang
- Department of Radiology, University of California, La Jolla, San Diego, CA 92093, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
| | - Christine B. Chung
- Department of Radiology, University of California, La Jolla, San Diego, CA 92093, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
| | - Jiang Du
- Department of Radiology, University of California, La Jolla, San Diego, CA 92093, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
| | - Eric Y. Chang
- Department of Radiology, University of California, La Jolla, San Diego, CA 92093, USA
- Radiology Service, Veterans Affairs San Diego Healthcare System, La Jolla, San Diego, CA 92161, USA
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14
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Lehtonen AJ, Arasalo O, Srbova L, Heilala M, Pokki J. Magnetic microrheometry of tumor-relevant stiffness levels and probabilistic quantification of viscoelasticity differences inside 3D cell culture matrices. PLoS One 2023; 18:e0282511. [PMID: 36947558 PMCID: PMC10032533 DOI: 10.1371/journal.pone.0282511] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 02/16/2023] [Indexed: 03/23/2023] Open
Abstract
The progression of breast cancer involves cancer-cell invasions of extracellular matrices. To investigate the progression, 3D cell cultures are widely used along with different types of matrices. Currently, the matrices are often characterized using parallel-plate rheometry for matrix viscoelasticity, or liquid-like viscous and stiffness-related elastic characteristics. The characterization reveals averaged information and sample-to-sample variation, yet, it neglects internal heterogeneity within matrices, experienced by cancer cells in 3D culture. Techniques using optical tweezers and magnetic microrheometry have measured heterogeneity in viscoelasticity in 3D culture. However, there is a lack of probabilistic heterogeneity quantification and cell-size-relevant, microscale-viscoelasticity measurements at breast-tumor tissue stiffness up to ≃10 kPa in Young's modulus. Here, we have advanced methods, for the purpose, which use a magnetic microrheometer that applies forces on magnetic spheres within matrices, and detects the spheres displacements. We present probabilistic heterogeneity quantification using microscale-viscoelasticity measurements in 3D culture matrices at breast-tumor-relevant stiffness levels. Bayesian multilevel modeling was employed to distinguish heterogeneity in viscoelasticity from the effects of experimental design and measurement errors. We report about the heterogeneity of breast-tumor-relevant agarose, GrowDex, GrowDex-collagen and fibrin matrices. The degree of heterogeneity differs for stiffness, and phase angle (i.e. ratio between viscous and elastic characteristics). Concerning stiffness, agarose and GrowDex show the lowest and highest heterogeneity, respectively. Concerning phase angle, fibrin and GrowDex-collagen present the lowest and the highest heterogeneity, respectively. While this heterogeneity information involves softer matrices, probed by ≃30 μm magnetic spheres, we employ larger ≃100 μm spheres to increase magnetic forces and acquire a sufficient displacement signal-to-noise ratio in stiffer matrices. Thus, we show pointwise microscale viscoelasticity measurements within agarose matrices up to Young's moduli of 10 kPa. These results establish methods that combine magnetic microrheometry and Bayesian multilevel modeling for enhanced heterogeneity analysis within 3D culture matrices.
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Affiliation(s)
- Arttu J Lehtonen
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
| | - Ossi Arasalo
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
| | - Linda Srbova
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
| | - Maria Heilala
- Department of Applied Physics, Aalto University, Espoo, Finland
| | - Juho Pokki
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
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15
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Kim Y, Ajayi PT, Bleck CKE, Glancy B. Three-dimensional remodelling of the cellular energy distribution system during postnatal heart development. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210322. [PMID: 36189814 PMCID: PMC9527916 DOI: 10.1098/rstb.2021.0322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 02/11/2022] [Indexed: 11/12/2022] Open
Abstract
The heart meets the high energy demands of constant muscle contraction and calcium cycling primarily through the conversion of fatty acids into adenosine triphosphate (ATP) by a large volume of mitochondria. As such, the spatial relationships among lipid droplets (LDs), mitochondria, the sarcotubular system and the contractile apparatus are critical to the efficient distribution of energy within the cardiomyocyte. However, the connectivity among components of the cardiac cellular energy distribution system during postnatal development remains unclear. Here, we use volume electron microscopy to demonstrate that the sarcomere branches uniting the myofibrillar network occur more than twice as frequently during early postnatal development as in mature cardiomyocytes. Moreover, we show that the mitochondrial networks arranged in parallel to the contractile apparatus are composed of larger, more compact mitochondria with greater connectivity to adjacent mitochondria in mature as compared with early postnatal cardiomyocytes. Finally, we find that connectivity among mitochondria, LDs and the sarcotubular network is greater in developing than in mature muscles. These data suggest that physical connectivity among cellular structures may facilitate the communication needed to coordinate developmental processes within the cardiac muscle cell. This article is part of the theme issue 'The cardiomyocyte: new revelations on the interplay between architecture and function in growth, health, and disease'.
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Affiliation(s)
- Yuho Kim
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
- Department of Physical Therapy and Kinesiology, University of Massachusetts Lowell, Lowell, MA 01854, USA
| | - Peter T. Ajayi
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Christopher K. E. Bleck
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Brian Glancy
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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16
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Katti P, Ajayi PT, Aponte A, Bleck CKE, Glancy B. Identification of evolutionarily conserved regulators of muscle mitochondrial network organization. Nat Commun 2022; 13:6622. [PMID: 36333356 PMCID: PMC9636386 DOI: 10.1038/s41467-022-34445-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 10/25/2022] [Indexed: 11/06/2022] Open
Abstract
Mitochondrial networks provide coordinated energy distribution throughout muscle cells. However, pathways specifying mitochondrial networks are incompletely understood and it is unclear how they might affect contractile fiber-type. Here, we show that natural energetic demands placed on Drosophila melanogaster muscles yield native cell-types among which contractile and mitochondrial network-types are regulated differentially. Proteomic analyses of indirect flight, jump, and leg muscles, together with muscles misexpressing known fiber-type specification factor salm, identified transcription factors H15 and cut as potential mitochondrial network regulators. We demonstrate H15 operates downstream of salm regulating flight muscle contractile and mitochondrial network-type. Conversely, H15 regulates mitochondrial network configuration but not contractile type in jump and leg muscles. Further, we find that cut regulates salm expression in flight muscles and mitochondrial network configuration in leg muscles. These data indicate cell type-specific regulation of muscle mitochondrial network organization through evolutionarily conserved transcription factors cut, salm, and H15.
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Affiliation(s)
- Prasanna Katti
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Peter T Ajayi
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Angel Aponte
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Christopher K E Bleck
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Brian Glancy
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, 20892, USA.
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17
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Katti P, Hall AS, Parry HA, Ajayi PT, Kim Y, Willingham TB, Bleck CKE, Wen H, Glancy B. Mitochondrial network configuration influences sarcomere and myosin filament structure in striated muscles. Nat Commun 2022; 13:6058. [PMID: 36229433 PMCID: PMC9561657 DOI: 10.1038/s41467-022-33678-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 09/28/2022] [Indexed: 12/24/2022] Open
Abstract
Sustained muscle contraction occurs through interactions between actin and myosin filaments within sarcomeres and requires a constant supply of adenosine triphosphate (ATP) from nearby mitochondria. However, it remains unclear how different physical configurations between sarcomeres and mitochondria alter the energetic support for contractile function. Here, we show that sarcomere cross-sectional area (CSA) varies along its length in a cell type-dependent manner where the reduction in Z-disk CSA relative to the sarcomere center is closely coordinated with mitochondrial network configuration in flies, mice, and humans. Further, we find myosin filaments near the sarcomere periphery are curved relative to interior filaments with greater curvature for filaments near mitochondria compared to sarcoplasmic reticulum. Finally, we demonstrate variable myosin filament lattice spacing between filament ends and filament centers in a cell type-dependent manner. These data suggest both sarcomere structure and myofilament interactions are influenced by the location and orientation of mitochondria within muscle cells.
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Affiliation(s)
- Prasanna Katti
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | | | - Hailey A Parry
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Peter T Ajayi
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Yuho Kim
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - T Bradley Willingham
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Christopher K E Bleck
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Han Wen
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Brian Glancy
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health Bethesda, Bethesda, MD, USA.
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18
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Sikic L, Schulman E, Kosklin A, Saraswathibhatla A, Chaudhuri O, Pokki J. Nanoscale Tracking Combined with Cell-Scale Microrheology Reveals Stepwise Increases in Force Generated by Cancer Cell Protrusions. NANO LETTERS 2022; 22:7742-7750. [PMID: 35950832 PMCID: PMC9523704 DOI: 10.1021/acs.nanolett.2c01327] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 07/26/2022] [Indexed: 06/15/2023]
Abstract
In early breast cancer progression, cancer cells invade through a nanoporous basement membrane (BM) as a first key step toward metastasis. This invasion is thought to be mediated by a combination of proteases, which biochemically degrade BM matrix, and physical forces, which mechanically open up holes in the matrix. To date, techniques that quantify cellular forces of BM invasion in 3D culture have been unavailable. Here, we developed cellular-force measurements for breast cancer cell invasion in 3D culture that combine multiple-particle tracking of force-induced BM-matrix displacements at the nanoscale, and magnetic microrheometry of localized matrix mechanics. We find that cancer-cell protrusions exert forces from picoNewtons up to nanoNewtons during invasion. Strikingly, the protrusions extension involves stepwise increases in force, in steps of 0.2 to 0.5 nN exerted from every 30 s to 6 min. Thus, this technique reveals previously unreported dynamics of force generation by invasive protrusions in cancer cells.
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Affiliation(s)
- Luka Sikic
- Department
of Electrical Engineering and Automation, Aalto University, Espoo, FI-02150,Finland
| | - Ester Schulman
- Department
of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
| | - Anna Kosklin
- Department
of Electrical Engineering and Automation, Aalto University, Espoo, FI-02150,Finland
| | - Aashrith Saraswathibhatla
- Department
of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
| | - Ovijit Chaudhuri
- Department
of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
| | - Juho Pokki
- Department
of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
- Department
of Electrical Engineering and Automation, Aalto University, Espoo, FI-02150,Finland
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19
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Haug M, Reischl B, Nübler S, Kiriaev L, Mázala DAG, Houweling PJ, North KN, Friedrich O, Head SI. Absence of the Z-disc protein α-actinin-3 impairs the mechanical stability of Actn3KO mouse fast-twitch muscle fibres without altering their contractile properties or twitch kinetics. Skelet Muscle 2022; 12:14. [PMID: 35733150 PMCID: PMC9219180 DOI: 10.1186/s13395-022-00295-8] [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: 11/09/2021] [Accepted: 05/03/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A common polymorphism (R577X) in the ACTN3 gene results in the complete absence of the Z-disc protein α-actinin-3 from fast-twitch muscle fibres in ~ 16% of the world's population. This single gene polymorphism has been subject to strong positive selection pressure during recent human evolution. Previously, using an Actn3KO mouse model, we have shown in fast-twitch muscles, eccentric contractions at L0 + 20% stretch did not cause eccentric damage. In contrast, L0 + 30% stretch produced a significant ~ 40% deficit in maximum force; here, we use isolated single fast-twitch skeletal muscle fibres from the Actn3KO mouse to investigate the mechanism underlying this. METHODS Single fast-twitch fibres are separated from the intact muscle by a collagenase digest procedure. We use label-free second harmonic generation (SHG) imaging, ultra-fast video microscopy and skinned fibre measurements from our MyoRobot automated biomechatronics system to study the morphology, visco-elasticity, force production and mechanical strength of single fibres from the Actn3KO mouse. Data are presented as means ± SD and tested for significance using ANOVA. RESULTS We show that the absence of α-actinin-3 does not affect the visco-elastic properties or myofibrillar force production. Eccentric contractions demonstrated that chemically skinned Actn3KO fibres are mechanically weaker being prone to breakage when eccentrically stretched. Furthermore, SHG images reveal disruptions in the myofibrillar alignment of Actn3KO fast-twitch fibres with an increase in Y-shaped myofibrillar branching. CONCLUSIONS The absence of α-actinin-3 from the Z-disc in fast-twitch fibres disrupts the organisation of the myofibrillar proteins, leading to structural weakness. This provides a mechanistic explanation for our earlier findings that in vitro intact Actn3KO fast-twitch muscles are significantly damaged by L0 + 30%, but not L0 + 20%, eccentric contraction strains. Our study also provides a possible mechanistic explanation as to why α-actinin-3-deficient humans have been reported to have a faster decline in muscle function with increasing age, that is, as sarcopenia reduces muscle mass and force output, the eccentric stress on the remaining functional α-actinin-3 deficient fibres will be increased, resulting in fibre breakages.
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Affiliation(s)
- Michael Haug
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Barbara Reischl
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Stefanie Nübler
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Leonit Kiriaev
- School of Medicine, Western Sydney University, Sydney, NSW, 2560, Australia.,School of Medical Science, University of New South Wales, Sydney, NSW, Australia
| | - Davi A G Mázala
- Department of Kinesiology, College of Health Professions, Towson University, Towson, MD, USA
| | - Peter J Houweling
- Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, VIC, Australia
| | - Kathryn N North
- Murdoch Children's Research Institute, Melbourne, VIC, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, VIC, Australia
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.,School of Medicine, Western Sydney University, Sydney, NSW, 2560, Australia.,School of Medical Science, University of New South Wales, Sydney, NSW, Australia
| | - Stewart I Head
- School of Medicine, Western Sydney University, Sydney, NSW, 2560, Australia. .,School of Medical Science, University of New South Wales, Sydney, NSW, Australia. .,Murdoch Children's Research Institute, Melbourne, VIC, Australia.
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20
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Ajayi PT, Katti P, Zhang Y, Willingham TB, Sun Y, Bleck CKE, Glancy B. Regulation of the evolutionarily conserved muscle myofibrillar matrix by cell type dependent and independent mechanisms. Nat Commun 2022; 13:2661. [PMID: 35562354 PMCID: PMC9106682 DOI: 10.1038/s41467-022-30401-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 04/29/2022] [Indexed: 12/29/2022] Open
Abstract
Skeletal muscles play a central role in human movement through forces transmitted by contraction of the sarcomere. We recently showed that mammalian sarcomeres are connected through frequent branches forming a singular, mesh-like myofibrillar matrix. However, the extent to which myofibrillar connectivity is evolutionarily conserved as well as mechanisms which regulate the specific architecture of sarcomere branching remain unclear. Here, we demonstrate the presence of a myofibrillar matrix in the tubular, but not indirect flight (IF) muscles within Drosophila melanogaster. Moreover, we find that loss of transcription factor H15 increases sarcomere branching frequency in the tubular jump muscles, and we show that sarcomere branching can be turned on in IF muscles by salm-mediated conversion to tubular muscles. Finally, we demonstrate that neurochondrin misexpression results in myofibrillar connectivity in IF muscles without conversion to tubular muscles. These data indicate an evolutionarily conserved myofibrillar matrix regulated by both cell-type dependent and independent mechanisms.
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Affiliation(s)
- Peter T Ajayi
- Muscle Energetics Laboratory, NHLBI, NIH, Bethesda, MD, 20892, USA
| | - Prasanna Katti
- Muscle Energetics Laboratory, NHLBI, NIH, Bethesda, MD, 20892, USA
| | - Yingfan Zhang
- Muscle Energetics Laboratory, NHLBI, NIH, Bethesda, MD, 20892, USA
| | | | - Ye Sun
- Electron Microscopy Core, NHLBI, NIH, Bethesda, MD, 20892, USA
| | | | - Brian Glancy
- Muscle Energetics Laboratory, NHLBI, NIH, Bethesda, MD, 20892, USA.
- NIAMS, NIH, Bethesda, MD, 20892, USA.
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21
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Khalid W, Arshad MS, Aslam N, Majid Noor M, Siddeeg A, Abdul Rahim M, Zubair Khalid M, Ali A, Maqbool Z. Meat myofibril: Chemical composition, sources and its potential for cardiac layers and strong skeleton muscle. INTERNATIONAL JOURNAL OF FOOD PROPERTIES 2022. [DOI: 10.1080/10942912.2022.2044847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Waseem Khalid
- Department of Food Science, Government College University, Faisalabad, Pakistan
| | | | - Noman Aslam
- Department of Food Science, Government College University, Faisalabad, Pakistan
| | - Muhammad Majid Noor
- Department of Food Science, Government College University, Faisalabad, Pakistan
| | - Azhari Siddeeg
- Department of Food Engineering and Technology, Faculty of Engineering and Technology, University of Gezira, Wad Medani, Sudan
| | | | | | - Anwar Ali
- Department of Epidemiology and Health Statistics, Xiangya School of Public Health, Central South University, HN, China
| | - Zahra Maqbool
- Department of Food Science, Government College University, Faisalabad, Pakistan
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22
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23
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Garza-Lopez E, Vue Z, Katti P, Neikirk K, Biete M, Lam J, Beasley HK, Marshall AG, Rodman TA, Christensen TA, Salisbury JL, Vang L, Mungai M, AshShareef S, Murray SA, Shao J, Streeter J, Glancy B, Pereira RO, Abel ED, Hinton A. Protocols for Generating Surfaces and Measuring 3D Organelle Morphology Using Amira. Cells 2021; 11:65. [PMID: 35011629 PMCID: PMC8750564 DOI: 10.3390/cells11010065] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 12/18/2021] [Accepted: 12/22/2021] [Indexed: 12/14/2022] Open
Abstract
High-resolution 3D images of organelles are of paramount importance in cellular biology. Although light microscopy and transmission electron microscopy (TEM) have provided the standard for imaging cellular structures, they cannot provide 3D images. However, recent technological advances such as serial block-face scanning electron microscopy (SBF-SEM) and focused ion beam scanning electron microscopy (FIB-SEM) provide the tools to create 3D images for the ultrastructural analysis of organelles. Here, we describe a standardized protocol using the visualization software, Amira, to quantify organelle morphologies in 3D, thereby providing accurate and reproducible measurements of these cellular substructures. We demonstrate applications of SBF-SEM and Amira to quantify mitochondria and endoplasmic reticulum (ER) structures.
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Affiliation(s)
- Edgar Garza-Lopez
- Hinton and Garza Lopez Family Consulting Company, Iowa City, IA 52246, USA;
| | - Zer Vue
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA; (Z.V.); (H.K.B.); (A.G.M.); (T.A.R.); (L.V.)
| | - Prasanna Katti
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA; (P.K.); (B.G.)
| | - Kit Neikirk
- Department of Biology, University of Hawaii at Hilo, Hilo, HI 96720, USA; (K.N.); (M.B.)
| | - Michelle Biete
- Department of Biology, University of Hawaii at Hilo, Hilo, HI 96720, USA; (K.N.); (M.B.)
| | - Jacob Lam
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (J.L.); (M.M.); (S.A.); (J.S.)
| | - Heather K. Beasley
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA; (Z.V.); (H.K.B.); (A.G.M.); (T.A.R.); (L.V.)
- Department of Biochemistry, Cancer Biology, Neuroscience and Pharmacology, School of Graduate Studies and Research, Meharry Medical College, Nashville, TN 37208, USA
| | - Andrea G. Marshall
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA; (Z.V.); (H.K.B.); (A.G.M.); (T.A.R.); (L.V.)
| | - Taylor A. Rodman
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA; (Z.V.); (H.K.B.); (A.G.M.); (T.A.R.); (L.V.)
| | - Trace A. Christensen
- Microscopy and Cell Analysis Core Facility, Mayo Clinic, Rochester, MN 55905, USA; (T.A.C.); (J.L.S.)
| | - Jeffrey L. Salisbury
- Microscopy and Cell Analysis Core Facility, Mayo Clinic, Rochester, MN 55905, USA; (T.A.C.); (J.L.S.)
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | - Larry Vang
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA; (Z.V.); (H.K.B.); (A.G.M.); (T.A.R.); (L.V.)
| | - Margaret Mungai
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (J.L.); (M.M.); (S.A.); (J.S.)
| | - Salma AshShareef
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (J.L.); (M.M.); (S.A.); (J.S.)
| | - Sandra A. Murray
- Department of Cell Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 52013, USA;
| | - Jianqiang Shao
- Central Microscopy Research Facility, University of Iowa, Iowa City, IA 52242, USA;
| | - Jennifer Streeter
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (J.L.); (M.M.); (S.A.); (J.S.)
- Fraternal Order of Eagles Diabetes Research Center, Iowa City, IA 52242, USA
| | - Brian Glancy
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA; (P.K.); (B.G.)
| | - Renata O. Pereira
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (J.L.); (M.M.); (S.A.); (J.S.)
- Fraternal Order of Eagles Diabetes Research Center, Iowa City, IA 52242, USA
| | - E. Dale Abel
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA; (J.L.); (M.M.); (S.A.); (J.S.)
- Fraternal Order of Eagles Diabetes Research Center, Iowa City, IA 52242, USA
| | - Antentor Hinton
- Hinton and Garza Lopez Family Consulting Company, Iowa City, IA 52246, USA;
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA; (Z.V.); (H.K.B.); (A.G.M.); (T.A.R.); (L.V.)
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24
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Fox CD, Mesquita PHC, Godwin JS, Angleri V, Damas F, Ruple BA, Sexton CL, Brown MD, Kavazis AN, Young KC, Ugrinowitsch C, Libardi CA, Roberts MD. Frequent Manipulation of Resistance Training Variables Promotes Myofibrillar Spacing Changes in Resistance-Trained Individuals. Front Physiol 2021; 12:773995. [PMID: 34975527 PMCID: PMC8715010 DOI: 10.3389/fphys.2021.773995] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/17/2021] [Indexed: 11/21/2022] Open
Abstract
We sought to determine if manipulating resistance training (RT) variables differentially altered the expression of select sarcoplasmic and myofibril proteins as well as myofibrillar spacing in myofibers. Resistance-trained men (n = 20; 26 ± 3 years old) trained for 8 weeks where a randomized leg performed either a standard (CON) or variable RT protocol (VAR: manipulation of load, volume, muscle action, and rest intervals at each RT session). A pre-training (PRE) vastus lateralis biopsy was obtained from a randomized single leg, and biopsies were obtained from both legs 96 h following the last training bout. The sarcoplasmic protein pool was assayed for proteins involved in energy metabolism, and the myofibril protein pool was assayed for relative myosin heavy chain (MHC) and actin protein abundances. Sections were also histologically analyzed to obtain myofibril spacing characteristics. VAR resulted in ~12% greater volume load (VL) compared to CON (p < 0.001). The mean fiber cross-sectional area increased following both RT protocols [CON: 14.6% (775.5 μm2), p = 0.006; VAR: 13.9% (743.2 μm2), p = 0.01 vs. PRE for both], but without significant differences between protocols (p = 0.79). Neither RT protocol affected a majority of assayed proteins related to energy metabolism, but both training protocols increased hexokinase 2 protein levels and decreased a mitochondrial beta-oxidation marker (VLCAD protein; p < 0.05). Citrate synthase activity levels increased with CON RT (p < 0.05), but not VAR RT. The relative abundance of MHC (summed isoforms) decreased with both training protocols (p < 0.05). However, the relative abundance of actin protein (summed isoforms) decreased with VAR only (13.5 and 9.0%, respectively; p < 0.05). A decrease in percent area occupied by myofibrils was observed from PRE to VAR (−4.87%; p = 0.048), but not for the CON (4.53%; p = 0.979). In contrast, there was an increase in percent area occupied by non-contractile space from PRE to VAR (10.14%; p = 0.048), but not PRE to CON (0.72%; p = 0.979). In conclusion, while both RT protocols increased muscle fiber hypertrophy, a higher volume-load where RT variables were frequently manipulated increased non-contractile spacing in resistance-trained individuals.
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Affiliation(s)
- Carlton D. Fox
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | | | - Joshua S. Godwin
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Vitor Angleri
- MUSCULAB, Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos, São Carlos, Brazil
| | - Felipe Damas
- MUSCULAB, Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos, São Carlos, Brazil
| | - Bradley A. Ruple
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Casey L. Sexton
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Michael D. Brown
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | | | - Kaelin C. Young
- School of Kinesiology, Auburn University, Auburn, AL, United States
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine – Auburn Campus, Auburn, AL, United States
| | - Carlos Ugrinowitsch
- School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Cleiton A. Libardi
- MUSCULAB, Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos, São Carlos, Brazil
- *Correspondence: Cleiton A. Libardi, ; Michael D. Roberts,
| | - Michael D. Roberts
- School of Kinesiology, Auburn University, Auburn, AL, United States
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine – Auburn Campus, Auburn, AL, United States
- *Correspondence: Cleiton A. Libardi, ; Michael D. Roberts,
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25
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Giardini F, Lazzeri E, Vitale G, Ferrantini C, Costantini I, Pavone FS, Poggesi C, Bocchi L, Sacconi L. Quantification of Myocyte Disarray in Human Cardiac Tissue. Front Physiol 2021; 12:750364. [PMID: 34867455 PMCID: PMC8635020 DOI: 10.3389/fphys.2021.750364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 09/24/2021] [Indexed: 11/13/2022] Open
Abstract
Proper three-dimensional (3D)-cardiomyocyte orientation is important for an effective tension production in cardiac muscle. Cardiac diseases can cause severe remodeling processes in the heart, such as cellular misalignment, that can affect both the electrical and mechanical functions of the organ. To date, a proven methodology to map and quantify myocytes disarray in massive samples is missing. In this study, we present an experimental pipeline to reconstruct and analyze the 3D cardiomyocyte architecture in massive samples. We employed tissue clearing, staining, and advanced microscopy techniques to detect sarcomeres in relatively large human myocardial strips with micrometric resolution. Z-bands periodicity was exploited in a frequency analysis approach to extract the 3D myofilament orientation, providing an orientation map used to characterize the tissue organization at different spatial scales. As a proof-of-principle, we applied the proposed method to healthy and pathologically remodeled human cardiac tissue strips. Preliminary results suggest the reliability of the method: strips from a healthy donor are characterized by a well-organized tissue, where the local disarray is log-normally distributed and slightly depends on the spatial scale of analysis; on the contrary, pathological strips show pronounced tissue disorganization, characterized by local disarray significantly dependent on the spatial scale of analysis. A virtual sample generator is developed to link this multi-scale disarray analysis with the underlying cellular architecture. This approach allowed us to quantitatively assess tissue organization in terms of 3D myocyte angular dispersion and may pave the way for developing novel predictive models based on structural data at cellular resolution.
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Affiliation(s)
- Francesco Giardini
- Laboratory of Non-Linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
| | - Erica Lazzeri
- Laboratory of Non-Linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy
| | - Giulia Vitale
- Division of Physiology, Department of Clinical and Experimental Medicine, University of Florence, Florence, Italy
| | - Cecilia Ferrantini
- Laboratory of Non-Linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy.,Division of Physiology, Department of Clinical and Experimental Medicine, University of Florence, Florence, Italy
| | - Irene Costantini
- Laboratory of Non-Linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy.,National Institute of Optics, National Research Council, University of Florence, Florence, Italy.,Department of Biology, University of Florence, Florence, Italy
| | - Francesco S Pavone
- Laboratory of Non-Linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy.,National Institute of Optics, National Research Council, University of Florence, Florence, Italy.,Department of Physics, University of Florence, Florence, Italy
| | - Corrado Poggesi
- Division of Physiology, Department of Clinical and Experimental Medicine, University of Florence, Florence, Italy
| | - Leonardo Bocchi
- Laboratory of Non-Linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy.,Department of Information Engineering, University of Florence, Florence, Italy
| | - Leonardo Sacconi
- Laboratory of Non-Linear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy.,National Institute of Optics, National Research Council, University of Florence, Florence, Italy.,Faculty of Medicine, Institute for Experimental Cardiovascular Medicine, University of Freiburg, Freiburg im Breisgau, Germany
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26
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Wu C, Chin CSM, Huang Q, Chan HY, Yu X, Roy VAL, Li WJ. Rapid nanomolding of nanotopography on flexible substrates to control muscle cell growth with enhanced maturation. MICROSYSTEMS & NANOENGINEERING 2021; 7:89. [PMID: 34754504 PMCID: PMC8571286 DOI: 10.1038/s41378-021-00316-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 08/20/2021] [Accepted: 09/13/2021] [Indexed: 05/11/2023]
Abstract
In vivo, multiple biophysical cues provided by highly ordered connective tissues of the extracellular matrix regulate skeletal muscle cells to align in parallel with one another. However, in routine in vitro cell culture environments, these key factors are often missing, which leads to changes in cell behavior. Here, we present a simple strategy for using optical media discs with nanogrooves and other polymer-based substrates nanomolded from the discs to directly culture muscle cells to study their response to the effect of biophysical cues such as nanotopography and substrate stiffness. We extend the range of study of biophysical cues for myoblasts by showing that they can sense ripple sizes as small as a 100 nm width and a 20 nm depth for myotube alignment, which has not been reported previously. The results revealed that nanotopography and substrate stiffness regulated myoblast proliferation and morphology independently, with nanotopographical cues showing a higher effect. These biophysical cues also worked synergistically, and their individual effects on cells were additive; i.e., by comparing cells grown on different polymer-based substrates (with and without nanogrooves), the cell proliferation rate could be reduced by as much as ~29%, and the elongation rate could be increased as much as ~116%. Moreover, during myogenesis, muscle cells actively responded to nanotopography and consistently showed increases in fusion and maturation indices of ~28% and ~21%, respectively. Finally, under electrical stimulation, the contraction amplitude of well-aligned myotubes was found to be almost 3 times greater than that for the cells on a smooth surface, regardless of the substrate stiffness.
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Affiliation(s)
- Cong Wu
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China
| | - Chriss S. M. Chin
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China
| | - Qingyun Huang
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China
| | - Ho-Yin Chan
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China
| | - Xinge Yu
- Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, China
| | | | - Wen J. Li
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China
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27
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Microtubule-based transport is essential to distribute RNA and nascent protein in skeletal muscle. Nat Commun 2021; 12:6079. [PMID: 34707124 PMCID: PMC8551216 DOI: 10.1038/s41467-021-26383-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 10/04/2021] [Indexed: 12/18/2022] Open
Abstract
While the importance of RNA localization in highly differentiated cells is well appreciated, basic principles of RNA localization in skeletal muscle remain poorly characterized. Here, we develop a method to detect and quantify single molecule RNA localization patterns in skeletal myofibers, and uncover a critical role for directed transport of RNPs in muscle. We find that RNAs localize and are translated along sarcomere Z-disks, dispersing tens of microns from progenitor nuclei, regardless of encoded protein function. We find that directed transport along the lattice-like microtubule network of myofibers becomes essential to achieve this localization pattern as muscle development progresses; disruption of this network leads to extreme accumulation of RNPs and nascent protein around myonuclei. Our observations suggest that global active RNP transport may be required to distribute RNAs in highly differentiated cells and reveal fundamental mechanisms of gene regulation, with consequences for myopathies caused by perturbations to RNPs or microtubules.
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28
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Willingham TB, Ajayi PT, Glancy B. Subcellular Specialization of Mitochondrial Form and Function in Skeletal Muscle Cells. Front Cell Dev Biol 2021; 9:757305. [PMID: 34722542 PMCID: PMC8554132 DOI: 10.3389/fcell.2021.757305] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 09/27/2021] [Indexed: 11/22/2022] Open
Abstract
Across different cell types and within single cells, mitochondria are heterogeneous in form and function. In skeletal muscle cells, morphologically and functionally distinct subpopulations of mitochondria have been identified, but the mechanisms by which the subcellular specialization of mitochondria contributes to energy homeostasis in working muscles remains unclear. Here, we discuss the current data regarding mitochondrial heterogeneity in skeletal muscle cells and highlight potential new lines of inquiry that have emerged due to advancements in cellular imaging technologies.
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Affiliation(s)
- T. Bradley Willingham
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, United States
| | - Peter T. Ajayi
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, United States
| | - Brian Glancy
- National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, United States
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, United States
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29
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Ruple BA, Godwin JS, Mesquita PHC, Osburn SC, Sexton CL, Smith MA, Ogletree JC, Goodlett MD, Edison JL, Ferrando AA, Fruge AD, Kavazis AN, Young KC, Roberts MD. Myofibril and Mitochondrial Area Changes in Type I and II Fibers Following 10 Weeks of Resistance Training in Previously Untrained Men. Front Physiol 2021; 12:728683. [PMID: 34630147 PMCID: PMC8497692 DOI: 10.3389/fphys.2021.728683] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 08/25/2021] [Indexed: 12/19/2022] Open
Abstract
Resistance training increases muscle fiber hypertrophy, but the morphological adaptations that occur within muscle fibers remain largely unresolved. Fifteen males with minimal training experience (24±4years, 23.9±3.1kg/m2 body mass index) performed 10weeks of conventional, full-body resistance training (2× weekly). Body composition, the radiological density of the vastus lateralis muscle using peripheral quantitative computed tomography (pQCT), and vastus lateralis muscle biopsies were obtained 1week prior to and 72h following the last training bout. Quantification of myofibril and mitochondrial areas in type I (positive for MyHC I) and II (positive for MyHC IIa/IIx) fibers was performed using immunohistochemistry (IHC) techniques. Relative myosin heavy chain and actin protein abundances per wet muscle weight as well as citrate synthase (CS) activity assays were also obtained on tissue lysates. Training increased whole-body lean mass, mid-thigh muscle cross-sectional area, mean and type II fiber cross-sectional areas (fCSA), and maximal strength values for leg press, bench press, and deadlift (p<0.05). The intracellular area occupied by myofibrils in type I or II fibers was not altered with training, suggesting a proportional expansion of myofibrils with fCSA increases. However, our histological analysis was unable to differentiate whether increases in myofibril number or girth occurred. Relative myosin heavy chain and actin protein abundances also did not change with training. IHC indicated training increased mitochondrial areas in both fiber types (p=0.018), albeit CS activity levels remained unaltered with training suggesting a discordance between these assays. Interestingly, although pQCT-derived muscle density increased with training (p=0.036), suggestive of myofibril packing, a positive association existed between training-induced changes in this metric and changes in mean fiber myofibril area (r=0.600, p=0.018). To summarize, our data imply that shorter-term resistance training promotes a proportional expansion of the area occupied by myofibrils and a disproportional expansion of the area occupied by mitochondria in type I and II fibers. Additionally, IHC and biochemical techniques should be viewed independently from one another given the lack of agreement between the variables assessed herein. Finally, the pQCT may be a viable tool to non-invasively track morphological changes (specifically myofibril density) in muscle tissue.
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Affiliation(s)
- Bradley A Ruple
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Joshua S Godwin
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | | | - Shelby C Osburn
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Casey L Sexton
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | - Morgan A Smith
- School of Kinesiology, Auburn University, Auburn, AL, United States
| | | | - Michael D Goodlett
- Athletics Department, Auburn University, Auburn, AL, United States.,Department of Geriatrics, Edward Via College of Osteopathic Medicine, Auburn, AL, United States
| | - Joseph L Edison
- Athletics Department, Auburn University, Auburn, AL, United States.,Department of Geriatrics, Edward Via College of Osteopathic Medicine, Auburn, AL, United States
| | - Arny A Ferrando
- Department of Geriatrics, Donald W. Reynolds Institute on Aging, University of Arkansas for Medical Sciences, Little Rock, AK, United States
| | - Andrew D Fruge
- Department of Nutrition, Dietetics and Hospitality Management, Auburn University, Auburn, AL, United States
| | | | - Kaelin C Young
- School of Kinesiology, Auburn University, Auburn, AL, United States.,Department of Geriatrics, Edward Via College of Osteopathic Medicine, Auburn, AL, United States
| | - Michael D Roberts
- School of Kinesiology, Auburn University, Auburn, AL, United States.,Department of Geriatrics, Edward Via College of Osteopathic Medicine, Auburn, AL, United States
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30
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Abstract
The design of the energy metabolism system in striated muscle remains a major area of investigation. Here, we review our current understanding and emerging hypotheses regarding the metabolic support of muscle contraction. Maintenance of ATP free energy, so called energy homeostasis, via mitochondrial oxidative phosphorylation is critical to sustained contractile activity, and this major design criterion is the focus of this review. Cell volume invested in mitochondria reduces the space available for generating contractile force, and this spatial balance between mitochondria acontractile elements to meet the varying sustained power demands across muscle types is another important design criterion. This is accomplished with remarkably similar mass-specific mitochondrial protein composition across muscle types, implying that it is the organization of mitochondria within the muscle cell that is critical to supporting sustained muscle function. Beyond the production of ATP, ubiquitous distribution of ATPases throughout the muscle requires rapid distribution of potential energy across these large cells. Distribution of potential energy has long been thought to occur primarily through facilitated metabolite diffusion, but recent analysis has questioned the importance of this process under normal physiological conditions. Recent structural and functional studies have supported the hypothesis that the mitochondrial reticulum provides a rapid energy distribution system via the conduction of the mitochondrial membrane potential to maintain metabolic homeostasis during contractile activity. We extensively review this aspect of the energy metabolism design contrasting it with metabolite diffusion models and how mitochondrial structure can play a role in the delivery of energy in the striated muscle.
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Affiliation(s)
- Brian Glancy
- Muscle Energetics Laboratory, National Heart, Lung, and Blood Insititute and National Institute of Arthritis and Musculoskeletal and Skin Disease, Bethesda, Maryland
- Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Insititute, Bethesda, Maryland
| | - Robert S Balaban
- Muscle Energetics Laboratory, National Heart, Lung, and Blood Insititute and National Institute of Arthritis and Musculoskeletal and Skin Disease, Bethesda, Maryland
- Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Insititute, Bethesda, Maryland
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31
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Muscle Fibre Typology as a Novel Risk Factor for Hamstring Strain Injuries in Professional Football (Soccer): A Prospective Cohort Study. Sports Med 2021; 52:177-185. [PMID: 34515974 DOI: 10.1007/s40279-021-01538-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/05/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Hamstring strain injuries (HSI) are prevalent in team sports and occur frequently in the later phase of matches. In the search for interindividual factors that determine muscle fatigue and possibly injury risk, muscle fibre typology is a likely candidate. OBJECTIVE The aim of the study was to determine whether muscle fibre typology is a risk factor for HSI. METHODS A prospective cohort study was conducted over three seasons in professional football players competing in the Belgian Jupiler Pro League (n = 118) and in the English Premier League (n = 47). A total of 27 HSI were sustained during this period. Muscle fibre typology was non-invasively estimated using proton magnetic resonance spectroscopy and was characterized as a fast, slow, or intermediate typology based on the carnosine concentration in the soleus. A multivariate Cox model was used to identify risk factors for HSI. RESULTS Football players exhibited a wide variety of muscle typologies (slow 44.9%, intermediate 39.8%, fast 15.3%). In the combined cohort, players with a fast typology displayed a 5.3-fold (95% confidence interval [CI] 1.92-14.8; P = 0.001) higher risk of sustaining an index HSI than slow typology players. This was also independently observed in both leagues separately as, respectively, a 6.7-fold (95% CI 1.3-34.1; P = 0.023) and a 5.1-fold (95% CI 1.2-20.4; P = 0.023) higher chance was found in fast typology players than in slow typology players of the Jupiler Pro League and the Premier League cohort. CONCLUSION We identified muscle fibre typology as a novel and potent risk factor for HSI in team sports.
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32
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Culver MN, Langan SP, Hutchison ZJ. What's all the hype with fibre type? Selective single fibre adaptations with lifelong endurance exercise. J Physiol 2021; 599:4413-4414. [PMID: 34464451 DOI: 10.1113/jp281986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 08/27/2021] [Indexed: 11/08/2022] Open
Affiliation(s)
- Meral N Culver
- Neurovascular Physiology Laboratory, School of Kinesiology, Auburn University, Auburn, AL, USA
| | - Sean P Langan
- Department of Kinesiology, Korey Stringer Institute, University of Connecticut, Storrs, CT, USA
| | - Zach J Hutchison
- Neurovascular Physiology Laboratory, School of Kinesiology, Auburn University, Auburn, AL, USA
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33
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Cass JA, Williams CD, Irving TC, Lauga E, Malingen S, Daniel TL, Sponberg SN. A mechanism for sarcomere breathing: volume change and advective flow within the myofilament lattice. Biophys J 2021; 120:4079-4090. [PMID: 34384761 DOI: 10.1016/j.bpj.2021.08.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 06/19/2021] [Accepted: 08/04/2021] [Indexed: 11/28/2022] Open
Abstract
During muscle contraction, myosin motors anchored to thick filaments bind to and slide actin thin filaments. These motors rely on energy derived from ATP, supplied, in part, by diffusion from the sarcoplasm to the interior of the lattice of actin and myosin filaments. The radial spacing of filaments in this lattice may change or remain constant during contraction. If the lattice is isovolumetric, it must expand when the muscle shortens. If, however, the spacing is constant or has a different pattern of axial and radial motion, then the lattice changes volume during contraction, driving fluid motion and assisting in the transport of molecules between the contractile lattice and the surrounding intracellular space. We first create an advective-diffusive-reaction flow model and show that the flow into and out of the sarcomere lattice would be significant in the absence of lattice expansion. Advective transport coupled to diffusion has the potential to substantially enhance metabolite exchange within the crowded sarcomere. Using time-resolved x-ray diffraction of contracting muscle, we next show that the contractile lattice is neither isovolumetric nor constant in spacing. Instead, lattice spacing is time varying, depends on activation, and can manifest as an effective time-varying Poisson ratio. The resulting fluid flow in the sarcomere lattice of synchronous insect flight muscles is even greater than expected for constant lattice spacing conditions. Lattice spacing depends on a variety of factors that produce radial force, including cross-bridges, titin-like molecules, and other structural proteins. Volume change and advective transport varies with the phase of muscle stimulation during periodic contraction but remains significant at all conditions. Although varying in magnitude, advective transport will occur in all cases in which the sarcomere is not isovolumetric. Akin to "breathing," advective-diffusive transport in sarcomeres is sufficient to promote metabolite exchange and may play a role in the regulation of contraction itself.
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Affiliation(s)
- Julie A Cass
- Allen Institute for Cell Science, Seattle, Washington; Department of Biology, University of Washington, Seattle, Washington
| | - C David Williams
- Department of Biology, University of Washington, Seattle, Washington; Applied ML Group, Microsoft CSE, Redmond, Washington
| | - Thomas C Irving
- BioCAT and CSRRI, Department of Biological Sciences, Illinois Institute of Technology, Chicago, Illinois
| | - Eric Lauga
- Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, United Kingdom
| | - Sage Malingen
- Department of Biology, University of Washington, Seattle, Washington
| | - Thomas L Daniel
- Department of Biology, University of Washington, Seattle, Washington.
| | - Simon N Sponberg
- School of Physics & School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia.
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Burbaum L, Schneider J, Scholze S, Böttcher RT, Baumeister W, Schwille P, Plitzko JM, Jasnin M. Molecular-scale visualization of sarcomere contraction within native cardiomyocytes. Nat Commun 2021; 12:4086. [PMID: 34215727 PMCID: PMC8253822 DOI: 10.1038/s41467-021-24049-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 05/27/2021] [Indexed: 02/06/2023] Open
Abstract
Sarcomeres, the basic contractile units of striated muscle, produce the forces driving muscular contraction through cross-bridge interactions between actin-containing thin filaments and myosin II-based thick filaments. Until now, direct visualization of the molecular architecture underlying sarcomere contractility has remained elusive. Here, we use in situ cryo-electron tomography to unveil sarcomere contraction in frozen-hydrated neonatal rat cardiomyocytes. We show that the hexagonal lattice of the thick filaments is already established at the neonatal stage, with an excess of thin filaments outside the trigonal positions. Structural assessment of actin polarity by subtomogram averaging reveals that thin filaments in the fully activated state form overlapping arrays of opposite polarity in the center of the sarcomere. Our approach provides direct evidence for thin filament sliding during muscle contraction and may serve as a basis for structural understanding of thin filament activation and actomyosin interactions inside unperturbed cellular environments.
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Affiliation(s)
- Laura Burbaum
- Department of Cellular and Molecular Biophysics, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jonathan Schneider
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Sarah Scholze
- Department of Molecular Medicine, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Ralph T Böttcher
- Department of Molecular Medicine, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Wolfgang Baumeister
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Petra Schwille
- Department of Cellular and Molecular Biophysics, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jürgen M Plitzko
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Marion Jasnin
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany.
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Müller D, Klamt T, Gentemann L, Heisterkamp A, Kalies SMK. Evaluation of laser induced sarcomere micro-damage: Role of damage extent and location in cardiomyocytes. PLoS One 2021; 16:e0252346. [PMID: 34086732 PMCID: PMC8177425 DOI: 10.1371/journal.pone.0252346] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 05/12/2021] [Indexed: 11/18/2022] Open
Abstract
Whereas it is evident that a well aligned and regular sarcomeric structure in cardiomyocytes is vital for heart function, considerably less is known about the contribution of individual elements to the mechanics of the entire cell. For instance, it is unclear whether altered Z-disc elements are the reason or the outcome of related cardiomyopathies. Therefore, it is crucial to gain more insight into this cellular organization. This study utilizes femtosecond laser-based nanosurgery to better understand sarcomeres and their repair upon damage. We investigated the influence of the extent and the location of the Z-disc damage. A single, three, five or ten Z-disc ablations were performed in neonatal rat cardiomyocytes. We employed image-based analysis using a self-written software together with different already published algorithms. We observed that cardiomyocyte survival associated with the damage extent, but not with the cell area or the total number of Z-discs per cell. The cell survival is independent of the damage position and can be compensated. However, the sarcomere alignment/orientation is changing over time after ablation. The contraction time is also independent of the extent of damage for the tested parameters. Additionally, we observed shortening rates between 6–7% of the initial sarcomere length in laser treated cardiomyocytes. This rate is an important indicator for force generation in myocytes. In conclusion, femtosecond laser-based nanosurgery together with image-based sarcomere tracking is a powerful tool to better understand the Z-disc complex and its force propagation function and role in cellular mechanisms.
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Affiliation(s)
- Dominik Müller
- Institute of Quantum Optics, Leibniz University Hannover, Hannover, Germany
- REBIRTH Research Center for Translational Regenerative Medicine, Hannover, Germany
- Lower Saxony Centre for Biomedical Engineering, Implant Research and Development (NIFE), Hannover, Germany
- * E-mail:
| | - Thorben Klamt
- Institute of Quantum Optics, Leibniz University Hannover, Hannover, Germany
- Lower Saxony Centre for Biomedical Engineering, Implant Research and Development (NIFE), Hannover, Germany
| | - Lara Gentemann
- Institute of Quantum Optics, Leibniz University Hannover, Hannover, Germany
- Lower Saxony Centre for Biomedical Engineering, Implant Research and Development (NIFE), Hannover, Germany
| | - Alexander Heisterkamp
- Institute of Quantum Optics, Leibniz University Hannover, Hannover, Germany
- REBIRTH Research Center for Translational Regenerative Medicine, Hannover, Germany
- Lower Saxony Centre for Biomedical Engineering, Implant Research and Development (NIFE), Hannover, Germany
| | - Stefan Michael Klaus Kalies
- Institute of Quantum Optics, Leibniz University Hannover, Hannover, Germany
- REBIRTH Research Center for Translational Regenerative Medicine, Hannover, Germany
- Lower Saxony Centre for Biomedical Engineering, Implant Research and Development (NIFE), Hannover, Germany
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36
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Kaya-Çopur A, Marchiano F, Hein MY, Alpern D, Russeil J, Luis NM, Mann M, Deplancke B, Habermann BH, Schnorrer F. The Hippo pathway controls myofibril assembly and muscle fiber growth by regulating sarcomeric gene expression. eLife 2021; 10:e63726. [PMID: 33404503 PMCID: PMC7815313 DOI: 10.7554/elife.63726] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/05/2021] [Indexed: 12/30/2022] Open
Abstract
Skeletal muscles are composed of gigantic cells called muscle fibers, packed with force-producing myofibrils. During development, the size of individual muscle fibers must dramatically enlarge to match with skeletal growth. How muscle growth is coordinated with growth of the contractile apparatus is not understood. Here, we use the large Drosophila flight muscles to mechanistically decipher how muscle fiber growth is controlled. We find that regulated activity of core members of the Hippo pathway is required to support flight muscle growth. Interestingly, we identify Dlg5 and Slmap as regulators of the STRIPAK phosphatase, which negatively regulates Hippo to enable post-mitotic muscle growth. Mechanistically, we show that the Hippo pathway controls timing and levels of sarcomeric gene expression during development and thus regulates the key components that physically mediate muscle growth. Since Dlg5, STRIPAK and the Hippo pathway are conserved a similar mechanism may contribute to muscle or cardiomyocyte growth in humans.
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Affiliation(s)
- Aynur Kaya-Çopur
- Aix Marseille University, CNRS, IBDM, Turing Center for Living SystemsMarseilleFrance
- Max Planck Institute of BiochemistryMartinsriedGermany
| | - Fabio Marchiano
- Aix Marseille University, CNRS, IBDM, Turing Center for Living SystemsMarseilleFrance
| | - Marco Y Hein
- Max Planck Institute of BiochemistryMartinsriedGermany
| | - Daniel Alpern
- Institute of Bioengineering, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Julie Russeil
- Institute of Bioengineering, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Nuno Miguel Luis
- Aix Marseille University, CNRS, IBDM, Turing Center for Living SystemsMarseilleFrance
| | - Matthias Mann
- Max Planck Institute of BiochemistryMartinsriedGermany
| | - Bart Deplancke
- Institute of Bioengineering, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Bianca H Habermann
- Aix Marseille University, CNRS, IBDM, Turing Center for Living SystemsMarseilleFrance
| | - Frank Schnorrer
- Aix Marseille University, CNRS, IBDM, Turing Center for Living SystemsMarseilleFrance
- Max Planck Institute of BiochemistryMartinsriedGermany
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37
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Weiner A. Step-by-step guide to post-acquisition correlation of confocal and FIB/SEM volumes using Amira software. Methods Cell Biol 2020; 162:333-351. [PMID: 33707018 DOI: 10.1016/bs.mcb.2020.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In recent years new methodologies and workflow pipelines for acquiring correlated fluorescence microscopy and volume electron microscopy datasets have been extensively described and made accessible to users of different levels. Post-acquisition image processing, and particularly correlation of the optical and electron data in a single integrated three-dimensional framework can be key for extracting valuable information, especially when imaging large sample volumes such as whole cells or tissues. These tasks remain challenging and are often rate-limiting to most users. Here we provide a step-by-step guide to image processing and manual correlation using ImageJ and Amira software of a confocal microscopy stack and a focused ion beam/scanning electron microscopy (FIB/SEM) tomogram acquired using a correlative pipeline. These previously published datasets capture a highly transient invasion event by the bacterium Shigella flexneri infecting an epithelial cell grown in culture, and are made available here in their pre-processed form for readers who wish to gain hands-on experience in image processing and correlation using existing data. In this guide we describe a simple protocol for correlation based on internal sample features clearly visible by both fluorescence and electron microscopy, which is normally sufficient when correlating standard fluorescence microscopy stacks with FIB/SEM data. While the guide describes the treatment of specific datasets, it is applicable to a wide variety of samples and different microscopy approaches that require basic correlation and visualization of two or more datasets in a single integrated framework.
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Affiliation(s)
- Allon Weiner
- Centre d'Immunologie et des Maladies Infectieuses, Cimi-Paris, Inserm, Sorbonne Université, Paris, France.
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