1
|
Liu C, Karabina A, Meller A, Bhattacharjee A, Agostino CJ, Bowman GR, Ruppel KM, Spudich JA, Leinwand LA. Homologous mutations in human β, embryonic, and perinatal muscle myosins have divergent effects on molecular power generation. Proc Natl Acad Sci U S A 2024; 121:e2315472121. [PMID: 38377203 PMCID: PMC10907259 DOI: 10.1073/pnas.2315472121] [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: 09/24/2023] [Accepted: 01/12/2024] [Indexed: 02/22/2024] Open
Abstract
Mutations at a highly conserved homologous residue in three closely related muscle myosins cause three distinct diseases involving muscle defects: R671C in β-cardiac myosin causes hypertrophic cardiomyopathy, R672C and R672H in embryonic skeletal myosin cause Freeman-Sheldon syndrome, and R674Q in perinatal skeletal myosin causes trismus-pseudocamptodactyly syndrome. It is not known whether their effects at the molecular level are similar to one another or correlate with disease phenotype and severity. To this end, we investigated the effects of the homologous mutations on key factors of molecular power production using recombinantly expressed human β, embryonic, and perinatal myosin subfragment-1. We found large effects in the developmental myosins but minimal effects in β myosin, and magnitude of changes correlated partially with clinical severity. The mutations in the developmental myosins dramatically decreased the step size and load-sensitive actin-detachment rate of single molecules measured by optical tweezers, in addition to decreasing overall enzymatic (ATPase) cycle rate. In contrast, the only measured effect of R671C in β myosin was a larger step size. Our measurements of step size and bound times predicted velocities consistent with those measured in an in vitro motility assay. Finally, molecular dynamics simulations predicted that the arginine to cysteine mutation in embryonic, but not β, myosin may reduce pre-powerstroke lever arm priming and ADP pocket opening, providing a possible structural mechanism consistent with the experimental observations. This paper presents direct comparisons of homologous mutations in several different myosin isoforms, whose divergent functional effects are a testament to myosin's highly allosteric nature.
Collapse
Affiliation(s)
- Chao Liu
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA94305
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA94305
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA94550
| | - Anastasia Karabina
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO80309
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO80309
- Kainomyx, Inc., Palo Alto, CA94304
| | - Artur Meller
- Department of Biochemistry and Biophysics, Washington University in St. Louis, St. Louis, MO63110
- Medical Scientist Training Program, Washington University in St. Louis, St. Louis, MO63110
| | - Ayan Bhattacharjee
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Colby J. Agostino
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Greg R. Bowman
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Kathleen M. Ruppel
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA94305
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA94305
- Kainomyx, Inc., Palo Alto, CA94304
| | - James A. Spudich
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA94305
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA94305
- Kainomyx, Inc., Palo Alto, CA94304
| | - Leslie A. Leinwand
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO80309
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO80309
| |
Collapse
|
2
|
Kao K, Geeves MA. Protocols for Myosin and Actin-Myosin Assays Using Rapid, Stopped-Flow Kinetics. Methods Mol Biol 2024; 2735:191-211. [PMID: 38038850 DOI: 10.1007/978-1-0716-3527-8_11] [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] [Indexed: 12/02/2023]
Abstract
Fast transient kinetics using stopped-flow fluorimetry is now a powerful method for defining the ATPase cycle of myosin and its subfragments and has found wide use in defining the difference between myosin isoforms, myosins carrying disease linked mutations, and the effect of small molecules on the ATPase cycle. Here the protocols for completing the classical assays of myosin and actin.myosin using the stopped-flow are described. The assays include ATP and ADP binding to myosin and actin.myosin, displacement of ADP from myosin and actin.myosin, and the cleavage of ATP to ADP and phosphate on myosin. Single and multiple turnover assays are also described.
Collapse
Affiliation(s)
- Kerry Kao
- School of Medicine & College of Engineering, University of Washington, Seattle, WA, USA
| | - Michael A Geeves
- School of Biosciences, University of Kent, Canterbury, Kent, UK.
| |
Collapse
|
3
|
Mohran S, Kooiker K, Mahoney-Schaefer M, Mandrycky C, Kao K, Tu AY, Freeman J, Moussavi-Harami F, Geeves M, Regnier M. The biochemically defined super relaxed state of myosin-A paradox. J Biol Chem 2024; 300:105565. [PMID: 38103642 PMCID: PMC10819765 DOI: 10.1016/j.jbc.2023.105565] [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: 09/12/2023] [Revised: 11/06/2023] [Accepted: 12/06/2023] [Indexed: 12/19/2023] Open
Abstract
The biochemical SRX (super-relaxed) state of myosin has been defined as a low ATPase activity state. This state can conserve energy when the myosin is not recruited for muscle contraction. The SRX state has been correlated with a structurally defined ordered (versus disordered) state of muscle thick filaments. The two states may be linked via a common interacting head motif (IHM) where the two heads of heavy meromyosin (HMM), or myosin, fold back onto each other and form additional contacts with S2 and the thick filament. Experimental observations of the SRX, IHM, and the ordered form of thick filaments, however, do not always agree, and result in a series of unresolved paradoxes. To address these paradoxes, we have reexamined the biochemical measurements of the SRX state for porcine cardiac HMM. In our hands, the commonly employed mantATP displacement assay was unable to quantify the population of the SRX state with all data fitting very well by a single exponential. We further show that mavacamten inhibits the basal ATPases of both porcine ventricle HMM and S1 (Ki, 0.32 and 1.76 μM respectively) while dATP activates HMM cooperatively without any evidence of an SRX state. A combination of our experimental observations and theories suggests that the displacement of mantATP in purified proteins is not a reliable assay to quantify the SRX population. This means that while the structurally defined IHM and ordered thick filaments clearly exist, great care must be employed when using the mantATP displacement assay.
Collapse
Affiliation(s)
- Saffie Mohran
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA
| | - Kristina Kooiker
- Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA; Division of Cardiology, University of Washington, Seattle, Washington, USA
| | | | - Christian Mandrycky
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA
| | - Kerry Kao
- Department of Bioengineering, University of Washington, Seattle, Washington, USA
| | - An-Yue Tu
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA
| | - Jeremy Freeman
- Division of Cardiology, University of Washington, Seattle, Washington, USA
| | - Farid Moussavi-Harami
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA; Division of Cardiology, University of Washington, Seattle, Washington, USA
| | - Michael Geeves
- School of Biosciences, University of Kent, Canterbury, UK.
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, Washington, USA; Center for Translational Muscle Research, University of Washington, Seattle, Washington, USA.
| |
Collapse
|
4
|
Mohran S, Steczina S, Mandrycky C, Kao K, Regnier M. Measuring the Contractile Kinetics of Isolated Myofibrils from Human-Induced Pluripotent Stem Cell Derived Cardiomyocyte (hiPSC-CM) Models of Cardiomyopathy. Methods Mol Biol 2024; 2735:213-233. [PMID: 38038851 DOI: 10.1007/978-1-0716-3527-8_12] [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] [Indexed: 12/02/2023]
Abstract
Isolated myofibrils provide biomechanical data at the contractile organelle level that are independent of cellular calcium handling and signaling pathways. These myofibrils can be harvested from animal tissue, human muscle biopsies, or stem cell-derived striated muscle. Here we present our myofibril isolation and rapid solution switching protocols, which allow for precise measurements of activation (kinetics and tension generation) and a biphasic relaxation relationship (initial slow isometric relaxation followed by a fast exponential decay in tension). This experiment is generated on a custom-built myofibril apparatus utilizing a two-photodiode array to detect micron level deflection of our forged glass tip force transducers. A complete activation/relaxation curve can be produced from a single myofibril in under 30 minutes.
Collapse
Affiliation(s)
- Saffie Mohran
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Center for Translational Muscle Research, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA
| | - Sonette Steczina
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Center for Translational Muscle Research, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA
| | - Christian Mandrycky
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Center for Translational Muscle Research, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA
| | - Kerry Kao
- Department of Bioengineering, University of Washington, Seattle, WA, USA
- Center for Translational Muscle Research, University of Washington, Seattle, WA, USA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, WA, USA.
- Center for Translational Muscle Research, University of Washington, Seattle, WA, USA.
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA.
| |
Collapse
|
5
|
van der Wal E, Iuliano A, In 't Groen SLM, Bholasing AP, Priesmann D, Sharma P, den Hamer B, Saggiomo V, Krüger M, Pijnappel WWMP, de Greef JC. Highly contractile 3D tissue engineered skeletal muscles from human iPSCs reveal similarities with primary myoblast-derived tissues. Stem Cell Reports 2023; 18:1954-1971. [PMID: 37774701 PMCID: PMC10656354 DOI: 10.1016/j.stemcr.2023.08.014] [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: 03/21/2022] [Revised: 08/30/2023] [Accepted: 08/31/2023] [Indexed: 10/01/2023] Open
Abstract
Skeletal muscle research is transitioning toward 3D tissue engineered in vitro models reproducing muscle's native architecture and supporting measurement of functionality. Human induced pluripotent stem cells (hiPSCs) offer high yields of cells for differentiation. It has been difficult to differentiate high-quality, pure 3D muscle tissues from hiPSCs that show contractile properties comparable to primary myoblast-derived tissues. Here, we present a transgene-free method for the generation of purified, expandable myogenic progenitors (MPs) from hiPSCs grown under feeder-free conditions. We defined a protocol with optimal hydrogel and medium conditions that allowed production of highly contractile 3D tissue engineered skeletal muscles with forces similar to primary myoblast-derived tissues. Gene expression and proteomic analysis between hiPSC-derived and primary myoblast-derived 3D tissues revealed a similar expression profile of proteins involved in myogenic differentiation and sarcomere function. The protocol should be generally applicable for the study of personalized human skeletal muscle tissue in health and disease.
Collapse
Affiliation(s)
- Erik van der Wal
- Department of Human Genetics, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Alessandro Iuliano
- Department of Clinical Genetics, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Department of Pediatrics, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Center for Lysosomal and Metabolic Diseases, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | - Stijn L M In 't Groen
- Department of Clinical Genetics, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Department of Pediatrics, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Center for Lysosomal and Metabolic Diseases, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | - Anjali P Bholasing
- Department of Clinical Genetics, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Department of Pediatrics, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Center for Lysosomal and Metabolic Diseases, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands
| | - Dominik Priesmann
- Institute of Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany; Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - Preeti Sharma
- Physical Chemistry and Soft Matter, Wageningen University and Research, 6708 WE Wageningen, the Netherlands
| | - Bianca den Hamer
- Department of Human Genetics, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Vittorio Saggiomo
- Department of BioNanoTechnology, Wageningen University and Research, 6708 WG Wageningen, the Netherlands
| | - Marcus Krüger
- Institute of Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany; Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - W W M Pim Pijnappel
- Department of Clinical Genetics, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Department of Pediatrics, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands; Center for Lysosomal and Metabolic Diseases, Erasmus University Medical Center, 3015 GE Rotterdam, the Netherlands.
| | - Jessica C de Greef
- Department of Human Genetics, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands.
| |
Collapse
|
6
|
Hennig K, Hardman D, Barata DM, Martins II, Bernabeu MO, Gomes ER, Roman W. Generating fast-twitch myotubes in vitro with an optogenetic-based, quantitative contractility assay. Life Sci Alliance 2023; 6:e202302227. [PMID: 37550008 PMCID: PMC10427763 DOI: 10.26508/lsa.202302227] [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: 06/19/2023] [Revised: 07/26/2023] [Accepted: 07/27/2023] [Indexed: 08/09/2023] Open
Abstract
The composition of fiber types within skeletal muscle impacts the tissue's physiological characteristics and susceptibility to disease and ageing. In vitro systems should therefore account for fiber-type composition when modelling muscle conditions. To induce fiber specification in vitro, we designed a quantitative contractility assay based on optogenetics and particle image velocimetry. We submitted cultured myotubes to long-term intermittent light-stimulation patterns and characterized their structural and functional adaptations. After several days of in vitro exercise, myotubes contract faster and are more resistant to fatigue. The enhanced contractile functionality was accompanied by advanced maturation such as increased width and up-regulation of neuron receptor genes. We observed an up-regulation in the expression of fast myosin heavy-chain isoforms, which induced a shift towards a fast-twitch phenotype. This long-term in vitro exercise strategy can be used to study fiber specification and refine muscle disease modelling.
Collapse
Affiliation(s)
- Katharina Hennig
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - David Hardman
- Centre for Medical Informatics, Usher Institute, The University of Edinburgh, Edinburgh, UK
| | - David Mb Barata
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Inês Ibb Martins
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Miguel O Bernabeu
- Centre for Medical Informatics, Usher Institute, The University of Edinburgh, Edinburgh, UK
- The Bayes Centre, The University of Edinburgh, Edinburgh, UK
| | - Edgar R Gomes
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - William Roman
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Australian Regenerative Medicine Institute, Monash University, Clayton, Australia
- Victoria Node, EMBL Australia, Clayton, Australia
| |
Collapse
|
7
|
Liu C, Karabina A, Meller A, Bhattacharjee A, Agostino CJ, Bowman GR, Ruppel KM, Spudich JA, Leinwand LA. Homologous mutations in β, embryonic, and perinatal muscle myosins have divergent effects on molecular power generation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.02.547385. [PMID: 37425764 PMCID: PMC10327197 DOI: 10.1101/2023.07.02.547385] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Mutations at a highly conserved homologous residue in three closely related muscle myosins cause three distinct diseases involving muscle defects: R671C in β -cardiac myosin causes hypertrophic cardiomyopathy, R672C and R672H in embryonic skeletal myosin cause Freeman Sheldon syndrome, and R674Q in perinatal skeletal myosin causes trismus-pseudocamptodactyly syndrome. It is not known if their effects at the molecular level are similar to one another or correlate with disease phenotype and severity. To this end, we investigated the effects of the homologous mutations on key factors of molecular power production using recombinantly expressed human β , embryonic, and perinatal myosin subfragment-1. We found large effects in the developmental myosins, with the most dramatic in perinatal, but minimal effects in β myosin, and magnitude of changes correlated partially with clinical severity. The mutations in the developmental myosins dramatically decreased the step size and load-sensitive actin-detachment rate of single molecules measured by optical tweezers, in addition to decreasing ATPase cycle rate. In contrast, the only measured effect of R671C in β myosin was a larger step size. Our measurements of step size and bound times predicted velocities consistent with those measured in an in vitro motility assay. Finally, molecular dynamics simulations predicted that the arginine to cysteine mutation in embryonic, but not β , myosin may reduce pre-powerstroke lever arm priming and ADP pocket opening, providing a possible structural mechanism consistent with the experimental observations. This paper presents the first direct comparisons of homologous mutations in several different myosin isoforms, whose divergent functional effects are yet another testament to myosin's highly allosteric nature.
Collapse
Affiliation(s)
- Chao Liu
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA 94305
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, CA 94550
| | - Anastasia Karabina
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO 80303
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO 80303
- Kainomyx, Inc., Palo Alto, CA 94304
| | - Artur Meller
- Department of Biochemistry and Biophysics, Washington University in St. Louis, St. Louis, MO 63110
- Medical Scientist Training Program, Washington University in St. Louis, St. Louis, MO 63110
| | - Ayan Bhattacharjee
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Colby J Agostino
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Greg R Bowman
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Kathleen M Ruppel
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA 94305
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305
- Kainomyx, Inc., Palo Alto, CA 94304
| | - James A Spudich
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA 94305
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305
- Kainomyx, Inc., Palo Alto, CA 94304
| | - Leslie A Leinwand
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO 80303
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO 80303
| |
Collapse
|
8
|
Chakraborty AD, Kooiker K, Kobak KA, Cheng Y, Lee CF, Razumova M, Granzier H H, Regnier M, Rabinovitch PS, Moussavi-Harami F, Chiao YA. Late-life Rapamycin Treatment Enhances Cardiomyocyte Relaxation Kinetics and Reduces Myocardial Stiffness. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.12.544619. [PMID: 37398078 PMCID: PMC10312630 DOI: 10.1101/2023.06.12.544619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Diastolic dysfunction is a key feature of the aging heart. We have shown that late-life treatment with mTOR inhibitor, rapamycin, reverses age-related diastolic dysfunction in mice but the molecular mechanisms of the reversal remain unclear. To dissect the mechanisms by which rapamycin improves diastolic function in old mice, we examined the effects of rapamycin treatment at the levels of single cardiomyocyte, myofibril and multicellular cardiac muscle. Compared to young cardiomyocytes, isolated cardiomyocytes from old control mice exhibited prolonged time to 90% relaxation (RT 90 ) and time to 90% Ca 2+ transient decay (DT 90 ), indicating slower relaxation kinetics and calcium reuptake with age. Late-life rapamycin treatment for 10 weeks completely normalized RT 90 and partially normalized DT 90 , suggesting improved Ca 2+ handling contributes partially to the rapamycin-induced improved cardiomyocyte relaxation. In addition, rapamycin treatment in old mice enhanced the kinetics of sarcomere shortening and Ca 2+ transient increase in old control cardiomyocytes. Myofibrils from old rapamycin-treated mice displayed increased rate of the fast, exponential decay phase of relaxation compared to old controls. The improved myofibrillar kinetics were accompanied by an increase in MyBP-C phosphorylation at S282 following rapamycin treatment. We also showed that late-life rapamycin treatment normalized the age-related increase in passive stiffness of demembranated cardiac trabeculae through a mechanism independent of titin isoform shift. In summary, our results showed that rapamycin treatment normalizes the age-related impairments in cardiomyocyte relaxation, which works conjointly with reduced myocardial stiffness to reverse age-related diastolic dysfunction.
Collapse
|
9
|
Kihara Y, Tanaka Y, Ikeda M, Homma J, Takagi R, Ishigaki K, Yamanouchi K, Honda H, Nagata S, Yamato M. In utero transplantation of myoblasts and adipose-derived mesenchymal stem cells to murine models of Duchenne muscular dystrophy does not lead to engraftment and frequently results in fetal death. Regen Ther 2022; 21:486-493. [PMID: 36313392 PMCID: PMC9596598 DOI: 10.1016/j.reth.2022.10.003] [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: 08/23/2022] [Revised: 09/19/2022] [Accepted: 10/09/2022] [Indexed: 11/07/2022] Open
Abstract
Introduction Duchenne muscular dystrophy (DMD) is a progressive disease that leads to damage of muscle and myocardium due to genetic abnormalities in the dystrophin gene. In utero cell transplantation that might facilitate allogenic transplantation is worth considering to treat this disease. Methods We performed allogeneic in utero transplantation of GFP-positive myoblasts and adipose-derived mesenchymal stem cells into murine DMD model animals. The transplantation route in this study was fetal intraperitoneal transplantation and transplacental transplantation. Transplanted animals were examined at 4-weeks old by immunofluorescence staining and RT-qPCR. Results No GFP-positive cells were found by immunofluorescence staining of skeletal muscle and no GFP mRNA was detected by RT-qPCR in any animal, transplantation method and cell type. Compared with previous reports, myoblast transplantation exhibited an equivalent mortality rate, but adipose-derived stem cell (ASC) transplantation produced a higher mortality rate. Conclusions In utero transplantation of myoblasts or ASCs to murine models of DMD does not lead to engraftment and, in ASC transplantation primarily, frequently results in fetal death.
Collapse
Affiliation(s)
- Yuki Kihara
- Department of Pediatrics, Tokyo Women’s Medical University, School of Medicine, 8-1 Kawada-cho, Shinjuku-ku, Tokyo, 162-8666 Japan,Institute of Advanced Biomedical Engineering and Science, Tokyo Women’s Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo, 162-8666 Japan
| | - Yukie Tanaka
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Japan
| | - Masanari Ikeda
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Japan
| | - Jun Homma
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women’s Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo, 162-8666 Japan
| | - Ryo Takagi
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women’s Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo, 162-8666 Japan
| | - Keiko Ishigaki
- Department of Pediatrics, Tokyo Women’s Medical University, School of Medicine, 8-1 Kawada-cho, Shinjuku-ku, Tokyo, 162-8666 Japan
| | - Keitaro Yamanouchi
- Department of Veterinary Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Japan
| | - Hiroaki Honda
- Human Disease Models, Institute of Laboratory Animals, Tokyo Women's Medical University, Tokyo, Japan
| | - Satoru Nagata
- Department of Pediatrics, Tokyo Women’s Medical University, School of Medicine, 8-1 Kawada-cho, Shinjuku-ku, Tokyo, 162-8666 Japan
| | - Masayuki Yamato
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women’s Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo, 162-8666 Japan,Corresponding author. Fax: +81 3-3359-6046.
| |
Collapse
|
10
|
Mao Q, Acharya A, Rodríguez-delaRosa A, Marchiano F, Dehapiot B, Al Tanoury Z, Rao J, Díaz-Cuadros M, Mansur A, Wagner E, Chardes C, Gupta V, Lenne PF, Habermann BH, Theodoly O, Pourquié O, Schnorrer F. Tension-driven multi-scale self-organisation in human iPSC-derived muscle fibers. eLife 2022; 11:76649. [PMID: 35920628 PMCID: PMC9377800 DOI: 10.7554/elife.76649] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 08/02/2022] [Indexed: 11/18/2022] Open
Abstract
Human muscle is a hierarchically organised tissue with its contractile cells called myofibers packed into large myofiber bundles. Each myofiber contains periodic myofibrils built by hundreds of contractile sarcomeres that generate large mechanical forces. To better understand the mechanisms that coordinate human muscle morphogenesis from tissue to molecular scales, we adopted a simple in vitro system using induced pluripotent stem cell-derived human myogenic precursors. When grown on an unrestricted two-dimensional substrate, developing myofibers spontaneously align and self-organise into higher-order myofiber bundles, which grow and consolidate to stable sizes. Following a transcriptional boost of sarcomeric components, myofibrils assemble into chains of periodic sarcomeres that emerge across the entire myofiber. More efficient myofiber bundling accelerates the speed of sarcomerogenesis suggesting that tension generated by bundling promotes sarcomerogenesis. We tested this hypothesis by directly probing tension and found that tension build-up precedes sarcomere assembly and increases within each assembling myofibril. Furthermore, we found that myofiber ends stably attach to other myofibers using integrin-based attachments and thus myofiber bundling coincides with stable myofiber bundle attachment in vitro. A failure in stable myofiber attachment results in a collapse of the myofibrils. Overall, our results strongly suggest that mechanical tension across sarcomeric components as well as between differentiating myofibers is key to coordinate the multi-scale self-organisation of muscle morphogenesis.
Collapse
Affiliation(s)
- Qiyan Mao
- Turing Centre for Living Systems, Aix Marseille University, CNRS, IDBM, Marseille, France
| | - Achyuth Acharya
- Turing Centre for Living Systems, Aix Marseille University, CNRS, IDBM, Marseille, France
| | | | - Fabio Marchiano
- Turing Centre for Living Systems, Aix Marseille University, CNRS, IDBM, Marseille, France
| | - Benoit Dehapiot
- Turing Centre for Living Systems, Aix Marseille University, CNRS, IDBM, Marseille, France
| | - Ziad Al Tanoury
- Department of Pathology, Brigham and Women's Hospital, Boston, United States
| | - Jyoti Rao
- Department of Pathology, Brigham and Women's Hospital, Boston, United States
| | | | - Arian Mansur
- Harvard Stem Cell Institute, Boston, United States
| | - Erica Wagner
- Department of Pathology, Brigham and Women's Hospital, Boston, United States
| | - Claire Chardes
- Turing Centre for Living Systems, Aix Marseille University, CNRS, IDBM, Marseille, France
| | - Vandana Gupta
- Department of Medicine, Brigham and Women's Hospital, Boston, United States
| | - Pierre-François Lenne
- Turing Centre for Living Systems, Aix Marseille University, CNRS, IDBM, Marseille, France
| | - Bianca H Habermann
- Turing Centre for Living Systems, Aix Marseille University, CNRS, IDBM, Marseille, France
| | - Olivier Theodoly
- Turing Centre for Living Systems, Aix Marseille University, CNRS, LAI, Marseille, France
| | - Olivier Pourquié
- Department of Genetics, Harvard Medical School, Boston, United States
| | - Frank Schnorrer
- Turing Centre for Living Systems, Aix Marseille University, CNRS, IDBM, Marseille, France
| |
Collapse
|
11
|
Coletti C, Acosta GF, Keslacy S, Coletti D. Exercise-mediated reinnervation of skeletal muscle in elderly people: An update. Eur J Transl Myol 2022; 32. [PMID: 35234025 PMCID: PMC8992679 DOI: 10.4081/ejtm.2022.10416] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 02/17/2022] [Indexed: 11/22/2022] Open
Abstract
Sarcopenia is defined by the loss of muscle mass and function. In aging sarcopenia is due to mild chronic inflammation but also to fiber-intrinsic defects, such as mitochondrial dysfunction. Age-related sarcopenia is associated with physical disability and lowered quality of life. In addition to skeletal muscle, the nervous tissue is also affected in elderly people. With aging, type 2 fast fibers preferentially undergo denervation and are reinnervated by slow-twitch motor neurons. They spread forming new neuro-muscular junctions with the denervated fibers: the result is an increased proportion of slow fibers that group together since they are associated in the same motor unit. Grouping and fiber type shifting are indeed major histological features of aging skeletal muscle. Exercise has been proposed as an intervention for age-related sarcopenia due to its numerous beneficial effects on muscle mechanical and biochemical features. In 2013, a precursor study in humans was published in the European Journal of Translation Myology (formerly known as Basic and Applied Myology), highlighting the occurrence of reinnervation in the musculature of aged, exercise-trained individuals as compared to the matching control. This paper, entitled «Reinnervation of Vastus lateralis is increased significantly in seniors (70-years old) with a lifelong history of high-level exercise», is now being reprinted for the second issue of the «Ejtm Seminal Paper Series». In this short review we discuss those results in the light of the most recent advances confirming the occurrence of exercise-mediated reinnervation, ultimately preserving muscle structure and function in elderly people who exercise.
Collapse
Affiliation(s)
- Claudia Coletti
- School of Kinesiology, Nutrition and Food Science, California State University Los Angeles, Los Angeles, CA.
| | - Gilberto F Acosta
- School of Kinesiology, Nutrition and Food Science, California State University Los Angeles, Los Angeles, CA.
| | - Stefan Keslacy
- School of Kinesiology, Nutrition and Food Science, California State University Los Angeles, Los Angeles, CA.
| | - Dario Coletti
- DAHFMO - Unit of Histology and Medical Embryology, Sapienza University of Rome, Rome, Italy; Biological Adaptation and Ageing, CNRS UMR 8256, Inserm U1164, Institut de Biologie Paris-Seine, Sorbonne Université, Paris, France; Interuniversity institute of Myology, Ro.
| |
Collapse
|
12
|
Treatment with platelet-rich plasma attenuates proprioceptor abnormalities in a rat model of postpartum stress urinary incontinence. Int Urogynecol J 2022; 33:2159-2167. [PMID: 35195739 DOI: 10.1007/s00192-022-05112-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Accepted: 01/27/2022] [Indexed: 12/23/2022]
Abstract
INTRODUCTION AND HYPOTHESIS Stress urinary incontinence (SUI) is the most prevalent form of urinary incontinence, and vaginal delivery is a major risk factor for developing SUI. We evaluated the hypothesis that applying the autologous platelet rich plasma (PRP) to the pelvic floor muscles via injection affects expression of proprioceptors and improves postpartum stress urinary incontinence (PSUI) in rats. METHODS Virgin female Sprague-Dawley rats were divided into control (n = 10) and experimental group(n = 20). Vaginal dilation was used to establish PSUI, and the rats in the experimental group were further divided into the PSUI group (n = 10) and PSUI+PRP group (n = 10). Pelvic floor muscles from rats in the PSUI+PRP group were positioned under ultrasound guidance for PRP injection. The morphology and number of pelvic floor muscle spindles were assessed using H&E staining, proprioceptors evaluated by gold chloride staining, and changes in the expression of neurotrophin-3 (NT-3) and skeletal myosin MY-32 determined by immunohistochemistry. RESULTS After 28 days,bladder leak point pressure (BLPP) and abdominal leaking-urine point pressure (ALPP) in rats with PSUI were significantly lower than in control animals (P<0.01). Both BLPP and ALPP increased significantly in the PSUI+PRP group (P<0.01). Compared with the control group, muscle spindle morphology and structure in the PSUI and PSUI+PRP groups had different pathological changes,with higher variations in the PSUI group. The positive signals for NT-3/MY-32 expression in control rats were higher than those from PSUI or PSUI+PRP groups, however, the expression for NT-3/MY-32 in PSUI+PRP animals was higher than that seen in the PSUI group (P < 0.01). CONCLUSIONS PSUI rats have an abnormal expression of pelvic proprioceptors, which affect proprioceptive function, and further the contractibility of pelvic floor muscles. A PRP injection may restore the sensory function of pelvic proprioceptors, thus improving urine leakage in PSUI rats.
Collapse
|
13
|
Francis MR, Pinniger GJ, Noble PB, Wang KCW. Intrauterine growth restriction affects diaphragm function in adult female and male mice. Pediatr Pulmonol 2020; 55:229-235. [PMID: 31535471 DOI: 10.1002/ppul.24519] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Accepted: 08/30/2019] [Indexed: 01/10/2023]
Abstract
BACKGROUND In utero diaphragm development is critically important for postnatal respiratory function and any disturbance to fetal development may lead to diaphragm dysfunction and respiratory complications in the postnatal period. Intrauterine growth restriction (IUGR) has been shown to affect respiratory function in a sex-dependent manner; however, the effect of IUGR on diaphragm function is unknown. AIM This study used a maternal hypoxia-induced mouse model of IUGR to investigate the impact of IUGR on diaphragm function and structure in male and female adult offspring. MATERIALS AND METHODS Pregnant BALB/c mice were housed under hypoxic conditions (10.5% O2 ) from gestational days 11 to 17.5 and then returned to normoxic conditions. Control mice were housed under normoxic conditions throughout pregnancy. At 8 weeks of age, offspring were euthanized and diaphragms isolated for functional assessment in organ bath experiments and for histological analysis. RESULTS IUGR offspring were lighter at birth and remained lighter at 8 weeks of age compared to Controls. While diaphragm force (maximal or twitch) was not affected by treatment or sex, the IUGR group exhibited a longer half-relaxation time after twitch contractions compared to Control. Female offspring had a lower maximum rate of force development and higher fatigue resistance compared to males, independent of IUGR. There was no difference in the diaphragm myofibre cross-sectional area between groups or sexes. CONCLUSION Sex and IUGR independently affect diaphragm contraction in adult mice without changes in structure. This study demonstrates that IUGR affects diaphragm contractile function in later life and could impair respiratory function if exacerbated under conditions of increased respiratory load.
Collapse
Affiliation(s)
- Maddison R Francis
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Gavin J Pinniger
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Peter B Noble
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Kimberley C W Wang
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia.,Telethon Kids Institute, The University of Western Australia, Perth, Western Australia, Australia
| |
Collapse
|
14
|
Xu B, Zhang M, Perlingeiro RCR, Shen W. Skeletal Muscle Constructs Engineered from Human Embryonic Stem Cell Derived Myogenic Progenitors Exhibit Enhanced Contractile Forces When Differentiated in a Medium Containing EGM‐2 Supplements. ACTA ACUST UNITED AC 2019; 3:e1900005. [DOI: 10.1002/adbi.201900005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 10/08/2019] [Indexed: 12/22/2022]
Affiliation(s)
- Bin Xu
- Department of Biomedical Engineering University of Minnesota Minneapolis MN 55455 USA
| | - Mengen Zhang
- Department of Biomedical Engineering University of Minnesota Minneapolis MN 55455 USA
| | - Rita C. R. Perlingeiro
- Department of Medicine University of Minnesota Minneapolis MN 55455 USA
- Stem Cell Institute and Institute for Engineering in Medicine University of Minnesota Minneapolis Minnesota 55455 USA
| | - Wei Shen
- Department of Biomedical Engineering University of Minnesota Minneapolis MN 55455 USA
- Stem Cell Institute and Institute for Engineering in Medicine University of Minnesota Minneapolis Minnesota 55455 USA
| |
Collapse
|
15
|
Mills RJ, Parker BL, Monnot P, Needham EJ, Vivien CJ, Ferguson C, Parton RG, James DE, Porrello ER, Hudson JE. Development of a human skeletal micro muscle platform with pacing capabilities. Biomaterials 2018; 198:217-227. [PMID: 30527761 DOI: 10.1016/j.biomaterials.2018.11.030] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 09/28/2018] [Accepted: 11/22/2018] [Indexed: 12/15/2022]
Abstract
Three dimensional engineered culture systems are powerful tools to rapidly expand our knowledge of human biology and identify novel therapeutic targets for disease. Bioengineered skeletal muscle has been recently shown to recapitulate many features of native muscle biology. However, current skeletal muscle bioengineering approaches require large numbers of cells, reagents and labour, limiting their potential for high-throughput studies. Herein, we use a miniaturized 96-well micro-muscle platform to facilitate semi-automated tissue formation, culture and analysis of human skeletal micro muscles (hμMs). Utilising an iterative screening approach we define a serum-free differentiation protocol that drives rapid, directed differentiation of human myoblast to skeletal myofibres. The resulting hμMs comprised organised bundles of striated and functional myofibres, which respond appropriately to electrical stimulation. Additionally, we developed an optogenetic approach to chronically stimulate hμM to recapitulate known features of exercise training including myofibre hypertrophy and increased expression of metabolic proteins. Taken together, our miniaturized approach provides a new platform to enable high-throughput studies of human skeletal muscle biology and exercise physiology.
Collapse
Affiliation(s)
- Richard J Mills
- School of Biomedical Sciences, The University of Queensland, St Lucia, 4072, Queensland, Australia; Centre for Cardiac and Vascular Biology, The University of Queensland, St Lucia, 4072, Queensland, Australia; QIMR Berghofer Medical Research Institute, Brisbane, 4006, Queensland, Australia
| | - Benjamin L Parker
- Charles Perkins Centre, School of Life and Environmental Science, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Pauline Monnot
- School of Biomedical Sciences, The University of Queensland, St Lucia, 4072, Queensland, Australia; Laboratoire de Biologie du Développement-Institut de Biologie, CNRS, Sorbonne Université, 75005, Paris, France
| | - Elise J Needham
- Charles Perkins Centre, School of Life and Environmental Science, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Celine J Vivien
- School of Biomedical Sciences, The University of Queensland, St Lucia, 4072, Queensland, Australia; Centre for Cardiac and Vascular Biology, The University of Queensland, St Lucia, 4072, Queensland, Australia; Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, 3052, Victoria, Australia
| | - Charles Ferguson
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, 4072, Queensland, Australia
| | - Robert G Parton
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, 4072, Queensland, Australia; Centre for Microscopy and Microanalysis, The University of Queensland, St Lucia, 4072, Queensland, Australia
| | - David E James
- Charles Perkins Centre, School of Life and Environmental Science, The University of Sydney, Sydney, 2006, NSW, Australia
| | - Enzo R Porrello
- School of Biomedical Sciences, The University of Queensland, St Lucia, 4072, Queensland, Australia; Centre for Cardiac and Vascular Biology, The University of Queensland, St Lucia, 4072, Queensland, Australia; Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, 3052, Victoria, Australia; Department of Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, 3010, Victoria, Australia.
| | - James E Hudson
- School of Biomedical Sciences, The University of Queensland, St Lucia, 4072, Queensland, Australia; Centre for Cardiac and Vascular Biology, The University of Queensland, St Lucia, 4072, Queensland, Australia; QIMR Berghofer Medical Research Institute, Brisbane, 4006, Queensland, Australia.
| |
Collapse
|
16
|
Rao DS, Kronert WA, Guo Y, Hsu KH, Sarsoza F, Bernstein SI. Reductions in ATPase activity, actin sliding velocity, and myofibril stability yield muscle dysfunction in Drosophila models of myosin-based Freeman-Sheldon syndrome. Mol Biol Cell 2018; 30:30-41. [PMID: 30379605 PMCID: PMC6337914 DOI: 10.1091/mbc.e18-08-0526] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Using Drosophila melanogaster, we created the first animal models for myosin-based Freeman–Sheldon syndrome (FSS), a dominant form of distal arthrogryposis defined by congenital facial and distal skeletal muscle contractures. Electron microscopy of homozygous mutant indirect flight muscles showed normal (Y583S) or altered (T178I, R672C) myofibril assembly followed by progressive disruption of the myofilament lattice. In contrast, all alleles permitted normal myofibril assembly in the heterozygous state but caused myofibrillar disruption during aging. The severity of myofibril defects in heterozygotes correlated with the level of flight impairment. Thus our Drosophila models mimic the human condition in that FSS mutations are dominant and display varied degrees of phenotypic severity. Molecular modeling indicates that the mutations disrupt communication between the nucleotide-binding site of myosin and its lever arm that drives force production. Each mutant myosin showed reduced in vitro actin sliding velocity, with the two more severe alleles significantly decreasing the catalytic efficiency of actin-activated ATP hydrolysis. The observed reductions in actin motility and catalytic efficiency may serve as the mechanistic basis of the progressive myofibrillar disarray observed in the Drosophila models as well as the prolonged contractile activity responsible for skeletal muscle contractures in FSS patients.
Collapse
Affiliation(s)
- Deepti S Rao
- Department of Biology, Molecular Biology Institute and Heart Institute, San Diego State University, San Diego, CA 92182-4614
| | - William A Kronert
- Department of Biology, Molecular Biology Institute and Heart Institute, San Diego State University, San Diego, CA 92182-4614
| | - Yiming Guo
- Department of Biology, Molecular Biology Institute and Heart Institute, San Diego State University, San Diego, CA 92182-4614
| | - Karen H Hsu
- Department of Biology, Molecular Biology Institute and Heart Institute, San Diego State University, San Diego, CA 92182-4614
| | - Floyd Sarsoza
- Department of Biology, Molecular Biology Institute and Heart Institute, San Diego State University, San Diego, CA 92182-4614
| | - Sanford I Bernstein
- Department of Biology, Molecular Biology Institute and Heart Institute, San Diego State University, San Diego, CA 92182-4614
| |
Collapse
|
17
|
Truskey GA. Development and application of human skeletal muscle microphysiological systems. LAB ON A CHIP 2018; 18:3061-3073. [PMID: 30183050 PMCID: PMC6177290 DOI: 10.1039/c8lc00553b] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A number of major disease states involve skeletal muscle, including type 2 diabetes, muscular dystrophy, sarcopenia and cachexia arising from cancer or heart disease. Animals do not accurately represent many of these disease states. Human skeletal muscle microphysiological systems derived from primary or induced pluripotent stem cells (hPSCs) can provide an in vitro model of genetic and chronic diseases and assess individual variations. Three-dimensional culture systems more accurately represent skeletal muscle function than do two-dimensional cultures. While muscle biopsies enable culture of primary muscle cells, hPSCs provide the opportunity to sample a wider population of donors. Recent advances to promote maturation of PSC-derived skeletal muscle provide an alternative to primary cells. While contractile function is often measured in three-dimensional cultures and several systems exist to characterize contraction of small numbers of muscle fibers, there is a need for functional measures of metabolism suited for microphysiological systems. Future research should address generation of well-differentiated hPSC-derived muscle cells, enabling muscle repair in vitro, and improved disease models.
Collapse
Affiliation(s)
- George A Truskey
- Department of Biomedical Engineering, Duke University, 1427 CIEMAS, 101 Science Drive, Durham, NC 27708-0281, USA.
| |
Collapse
|
18
|
Rao L, Qian Y, Khodabukus A, Ribar T, Bursac N. Engineering human pluripotent stem cells into a functional skeletal muscle tissue. Nat Commun 2018; 9:126. [PMID: 29317646 PMCID: PMC5760720 DOI: 10.1038/s41467-017-02636-4] [Citation(s) in RCA: 185] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 12/14/2017] [Indexed: 12/24/2022] Open
Abstract
The generation of functional skeletal muscle tissues from human pluripotent stem cells (hPSCs) has not been reported. Here, we derive induced myogenic progenitor cells (iMPCs) via transient overexpression of Pax7 in paraxial mesoderm cells differentiated from hPSCs. In 2D culture, iMPCs readily differentiate into spontaneously contracting multinucleated myotubes and a pool of satellite-like cells endogenously expressing Pax7. Under optimized 3D culture conditions, iMPCs derived from multiple hPSC lines reproducibly form functional skeletal muscle tissues (iSKM bundles) containing aligned multi-nucleated myotubes that exhibit positive force-frequency relationship and robust calcium transients in response to electrical or acetylcholine stimulation. During 1-month culture, the iSKM bundles undergo increased structural and molecular maturation, hypertrophy, and force generation. When implanted into dorsal window chamber or hindlimb muscle in immunocompromised mice, the iSKM bundles survive, progressively vascularize, and maintain functionality. iSKM bundles hold promise as a microphysiological platform for human muscle disease modeling and drug development.
Collapse
Affiliation(s)
- Lingjun Rao
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Ying Qian
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Alastair Khodabukus
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Thomas Ribar
- Duke iPSC Shared Resource Facility, Duke University, Durham, NC, 27708, USA
| | - Nenad Bursac
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA.
| |
Collapse
|
19
|
Lev R, Seliktar D. Hydrogel biomaterials and their therapeutic potential for muscle injuries and muscular dystrophies. J R Soc Interface 2018; 15:20170380. [PMID: 29343633 PMCID: PMC5805959 DOI: 10.1098/rsif.2017.0380] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 12/18/2017] [Indexed: 12/23/2022] Open
Abstract
Muscular diseases such as muscular dystrophies and muscle injuries constitute a large group of ailments that manifest as muscle weakness, atrophy or fibrosis. Although cell therapy is a promising treatment option, the delivery and retention of cells in the muscle is difficult and prevents sustained regeneration needed for adequate functional improvements. Various types of biomaterials with different physical and chemical properties have been developed to improve the delivery of cells and/or growth factors for treating muscle injuries. Hydrogels are a family of materials with distinct advantages for use as cell delivery systems in muscle injuries and ailments, including their mild processing conditions, their similarities to natural tissue extracellular matrix, and their ability to be delivered with less invasive approaches. Moreover, hydrogels can be made to completely degrade in the body, leaving behind their biological payload in a process that can enhance the therapeutic process. For these reasons, hydrogels have shown great potential as cell delivery matrices. This paper reviews a few of the hydrogel systems currently being applied together with cell therapy and/or growth factor delivery to promote the therapeutic repair of muscle injuries and muscle wasting diseases such as muscular dystrophies.
Collapse
Affiliation(s)
- Rachel Lev
- Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Dror Seliktar
- Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel
| |
Collapse
|
20
|
Nowakowski SG, Regnier M, Daggett V. Molecular mechanisms underlying deoxy-ADP.Pi activation of pre-powerstroke myosin. Protein Sci 2017; 26:749-762. [PMID: 28097776 DOI: 10.1002/pro.3121] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 01/05/2017] [Accepted: 01/06/2017] [Indexed: 01/19/2023]
Abstract
Myosin activation is a viable approach to treat systolic heart failure. We previously demonstrated that striated muscle myosin is a promiscuous ATPase that can use most nucleoside triphosphates as energy substrates for contraction. When 2-deoxy ATP (dATP) is used, it acts as a myosin activator, enhancing cross-bridge binding and cycling. In vivo, we have demonstrated that elevated dATP levels increase basal cardiac function and rescues function of infarcted rodent and pig hearts. Here we investigate the molecular mechanism underlying this physiological effect. We show with molecular dynamics simulations that the binding of dADP.Pi (dATP hydrolysis products) to myosin alters the structure and dynamics of the nucleotide binding pocket, myosin cleft conformation, and actin binding sites, which collectively yield a myosin conformation that we predict favors weak, electrostatic binding to actin. In vitro motility assays at high ionic strength were conducted to test this prediction and we found that dATP increased motility. These results highlight alterations to myosin that enhance cross-bridge formation and reveal a potential mechanism that may underlie dATP-induced improvements in cardiac function.
Collapse
Affiliation(s)
- Sarah G Nowakowski
- Department of Bioengineering, University of Washington, Seattle, Washington, 98195-5013
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, Washington, 98195-5013.,Center for Cardiovascular Biology, University of Washington, Seattle, Washington, 98195-5013
| | - Valerie Daggett
- Department of Bioengineering, University of Washington, Seattle, Washington, 98195-5013
| |
Collapse
|
21
|
Khodabukus A, Baar K. Factors That Affect Tissue-Engineered Skeletal Muscle Function and Physiology. Cells Tissues Organs 2016; 202:159-168. [DOI: 10.1159/000446067] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2016] [Indexed: 11/19/2022] Open
Abstract
Tissue-engineered skeletal muscle has the promise to be a tool for studying physiology, screening muscle-active drugs, and clinical replacement of damaged muscle. To maximize the potential benefits of engineered muscle, it is important to understand the factors required for tissue formation and how these affect muscle function. In this review, we evaluate how biomaterials, cell source, media components, and bioreactor interventions impact muscle function and phenotype.
Collapse
|
22
|
Walklate J, Ujfalusi Z, Geeves MA. Myosin isoforms and the mechanochemical cross-bridge cycle. ACTA ACUST UNITED AC 2016; 219:168-74. [PMID: 26792327 DOI: 10.1242/jeb.124594] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
At the latest count the myosin family includes 35 distinct groups, all of which have the conserved myosin motor domain attached to a neck or lever arm, followed by a highly variable tail or cargo binding region. The motor domain has an ATPase activity that is activated by the presence of actin. One feature of the myosin ATPase cycle is that it involves an association/dissociation with actin for each ATP hydrolysed. The cycle has been described in detail for a large number of myosins from different classes. In each case the cycle is similar, but the balance between the different molecular events in the cycle has been altered to produce a range of very different mechanical activities. Myosin may spend most of the ATPase cycle attached to actin (high duty ratio), as in the processive myosin (e.g. myosin V) or the strain-sensing myosins (e.g. myosin 1c). In contrast, most muscle myosins spend 80% of their ATPase cycle detached from actin. Within the myosin IIs found in human muscle, there are 11 different sarcomeric myosin isoforms, two smooth muscle isoforms as well as three non-muscle isoforms. We have been exploring how the different myosin isoforms have adapted the cross-bridge cycle to generate different types of mechanical activity and how this goes wrong in inherited myopathies. The ideas are outlined here.
Collapse
Affiliation(s)
| | - Zoltan Ujfalusi
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK
| | - Michael A Geeves
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK
| |
Collapse
|
23
|
Walklate J, Vera C, Bloemink MJ, Geeves MA, Leinwand L. The Most Prevalent Freeman-Sheldon Syndrome Mutations in the Embryonic Myosin Motor Share Functional Defects. J Biol Chem 2016; 291:10318-31. [PMID: 26945064 PMCID: PMC4858979 DOI: 10.1074/jbc.m115.707489] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Indexed: 11/12/2022] Open
Abstract
The embryonic myosin isoform is expressed during fetal development and rapidly down-regulated after birth. Freeman-Sheldon syndrome (FSS) is a disease associated with missense mutations in the motor domain of this myosin. It is the most severe form of distal arthrogryposis, leading to overcontraction of the hands, feet, and orofacial muscles and other joints of the body. Availability of human embryonic muscle tissue has been a limiting factor in investigating the properties of this isoform and its mutations. Using a recombinant expression system, we have studied homogeneous samples of human motors for the WT and three of the most common FSS mutants: R672H, R672C, and T178I. Our data suggest that the WT embryonic myosin motor is similar in contractile speed to the slow type I/β cardiac based on the rate constant for ADP release and ADP affinity for actin-myosin. All three FSS mutations show dramatic changes in kinetic properties, most notably the slowing of the apparent ATP hydrolysis step (reduced 5–9-fold), leading to a longer lived detached state and a slowed Vmax of the ATPase (2–35-fold), indicating a slower cycling time. These mutations therefore seriously disrupt myosin function.
Collapse
Affiliation(s)
- Jonathan Walklate
- From the School of Biosciences, University of Kent, Canterbury CT2 7NJ, United Kingdom and
| | - Carlos Vera
- the Department of Molecular and Developmental Biology, University of Colorado, Boulder, Colorado 80309
| | - Marieke J Bloemink
- From the School of Biosciences, University of Kent, Canterbury CT2 7NJ, United Kingdom and
| | - Michael A Geeves
- From the School of Biosciences, University of Kent, Canterbury CT2 7NJ, United Kingdom and
| | - Leslie Leinwand
- the Department of Molecular and Developmental Biology, University of Colorado, Boulder, Colorado 80309
| |
Collapse
|
24
|
Cheng Y, Hogarth KA, O'Sullivan ML, Regnier M, Pyle WG. 2-Deoxyadenosine triphosphate restores the contractile function of cardiac myofibril from adult dogs with naturally occurring dilated cardiomyopathy. Am J Physiol Heart Circ Physiol 2016; 310:H80-91. [PMID: 26497964 PMCID: PMC4796460 DOI: 10.1152/ajpheart.00530.2015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 10/08/2015] [Indexed: 11/22/2022]
Abstract
Dilated cardiomyopathy (DCM) is a major type of heart failure resulting from loss of systolic function. Naturally occurring canine DCM is a widely accepted experimental paradigm for studying human DCM. 2-Deoxyadenosine triphosphate (dATP) can be used by myosin and is a superior energy substrate over ATP for cross-bridge formation and increased systolic function. The objective of this study was to evaluate the beneficial effect of dATP on contractile function of cardiac myofibrils from dogs with naturally occurring DCM. We measured actomyosin NTPase activity and contraction/relaxation properties of isolated myofibrils from nonfailing (NF) and DCM canine hearts. NTPase assays indicated replacement of ATP with dATP significantly increased myofilament activity in both NF and DCM samples. dATP significantly improved maximal tension of DCM myofibrils to the NF sample level. dATP also restored Ca(2+) sensitivity of tension that was reduced in DCM samples. Similarly, dATP increased the kinetics of contractile activation (kACT), with no impact on the rate of cross-bridge tension redevelopment (kTR). Thus, the activation kinetics (kACT/kTR) that were reduced in DCM samples were restored for dATP to NF sample levels. dATP had little effect on relaxation. The rate of early slow-phase relaxation was slightly reduced with dATP, but its duration was not, nor was the fast-phase relaxation or times to 50 and 90% relaxation. Our findings suggest that myosin utilization of dATP improves cardiac myofibril contractile properties of naturally occurring DCM canine samples, restoring them to NF levels, without compromising relaxation. This suggests elevation of cardiac dATP is a promising approach for the treatment of DCM.
Collapse
Affiliation(s)
- Yuanhua Cheng
- Department of Bioengineering, University of Washington, Seattle, Washington
| | - Kaley A Hogarth
- Centre for Cardiovascular Investigations, Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada; and
| | - M Lynne O'Sullivan
- Department of Clinical Studies, University of Guelph, Guelph, Ontario, Canada
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, Washington
| | - W Glen Pyle
- Centre for Cardiovascular Investigations, Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada; and
| |
Collapse
|
25
|
Racca AW, Klaiman JM, Pioner JM, Cheng Y, Beck AE, Moussavi-Harami F, Bamshad MJ, Regnier M. Contractile properties of developing human fetal cardiac muscle. J Physiol 2015; 594:437-52. [PMID: 26460603 DOI: 10.1113/jp271290] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 10/06/2015] [Indexed: 01/10/2023] Open
Abstract
KEY POINTS The contractile properties of human fetal cardiac muscle have not been previously studied. Small-scale approaches such as isolated myofibril and isolated contractile protein biomechanical assays allow study of activation and relaxation kinetics of human fetal cardiac muscle under well-controlled conditions. We have examined the contractile properties of human fetal cardiac myofibrils and myosin across gestational age 59-134 days. Human fetal cardiac myofibrils have low force and slow kinetics of activation and relaxation that increase during the time period studied, and kinetic changes may result from structural maturation and changes in protein isoform expression. Understanding the time course of human fetal cardiac muscle structure and contractile maturation can provide a framework to study development of contractile dysfunction with disease and evaluate the maturation state of cultured stem cell-derived cardiomyocytes. ABSTRACT Little is known about the contractile properties of human fetal cardiac muscle during development. Understanding these contractile properties, and how they change throughout development, can provide valuable insight into human heart development, and provide a framework to study the early stages of cardiac diseases that develop in utero. We characterized the contractile properties of isolated human fetal cardiac myofibrils across 8-19 weeks of gestation. Mechanical measurements revealed that in early stages of gestation there is low specific force and slow rates of force development and relaxation, with increases in force and the rates of activation and relaxation as gestation progresses. The duration and slope of the initial, slow phase of relaxation, related to myosin detachment and thin filament deactivation rates, decreased with gestation age. F-actin sliding on human fetal cardiac myosin-coated surfaces slowed significantly from 108 to 130 days of gestation. Electron micrographs showed human fetal muscle myofibrils elongate and widen with age, but features such as the M-line and Z-band are apparent even as early as day 52. Protein isoform analysis revealed that β-myosin is predominantly expressed even at the earliest time point studied, but there is a progressive increase in expression of cardiac troponin I (TnI), with a concurrent decrease in slow skeletal TnI. Together, our results suggest that cardiac myofibril force production and kinetics of activation and relaxation change significantly with gestation age and are influenced by the structural maturation of the sarcomere and changes in contractile filament protein isoforms.
Collapse
Affiliation(s)
- Alice W Racca
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Jordan M Klaiman
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - J Manuel Pioner
- Department of Experimental and Clinical Medicine, Division of Physiology, University of Florence, Italy
| | - Yuanhua Cheng
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Anita E Beck
- Department of Pediatrics, University of Washington, Seattle, WA, USA.,Seattle Children's Hospital, Seattle, WA, USA
| | - Farid Moussavi-Harami
- Division of Cardiology, Department of Internal Medicine, University of Washington, Seattle, WA, USA
| | - Michael J Bamshad
- Department of Pediatrics, University of Washington, Seattle, WA, USA.,Seattle Children's Hospital, Seattle, WA, USA
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, WA, USA.,Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA.,Center for Cardiovascular Biology, University of Washington, Seattle, WA, USA
| |
Collapse
|
26
|
Rao V, Cheng Y, Lindert S, Wang D, Oxenford L, McCulloch AD, McCammon JA, Regnier M. PKA phosphorylation of cardiac troponin I modulates activation and relaxation kinetics of ventricular myofibrils. Biophys J 2015; 107:1196-1204. [PMID: 25185555 DOI: 10.1016/j.bpj.2014.07.027] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 07/10/2014] [Accepted: 07/15/2014] [Indexed: 10/24/2022] Open
Abstract
Protein kinase A (PKA) phosphorylation of myofibril proteins constitutes an important pathway for β-adrenergic modulation of cardiac contractility and relaxation. PKA targets the N-terminus (Ser-23/24) of cardiac troponin I (cTnI), cardiac myosin-binding protein C (cMyBP-C) and titin. The effect of PKA-mediated phosphorylation on the magnitude of contraction has been studied in some detail, but little is known about how it modulates the kinetics of thin filament activation and myofibril relaxation as Ca(2+) levels vary. Troponin C (cTnC) interaction with cTnI (C-I interaction) is a critical step in contractile activation that can be modulated by cTnI phosphorylation. We tested the hypothesis that altering C-I interactions by PKA, or by cTnI phosphomimetic mutations (S23D/S24D-cTnI), directly affects thin filament activation and myofilament relaxation kinetics. Rat ventricular myofibrils were isolated and endogenous cTn was exchanged with either wild-type cTnI, or S23D/S24D-cTnI recombinant cTn. Contractile mechanics were monitored at maximum and submaximal Ca(2+) concentrations. PKA treatment of wild-type cTn or exchange of cTn containing S23D/S24D-cTnI resulted in an increase in the rate of early, slow phase of relaxation (kREL,slow) and a decrease in its duration (tREL,slow). These effects were greater for submaximal Ca(2+) activated contractions. PKA treatment also reduced the rate of contractile activation (kACT) at maximal, but not submaximal Ca(2+), and reduced the Ca(2+) sensitivity of contraction. Using a fluorescent probe coupled to cTnC (C35S-IANBD), the Ca(2+)-cTn binding affinity and C-I interaction were monitored. Ca(2+) binding to cTn (pCa50) was significantly decreased when cTnI was phosphorylated by PKA (ΔpCa50 = 0.31). PKA phosphorylation of cTnI also weakened C-I interaction in the presence of Ca(2+). These data suggest that weakened C-I interaction, via PKA phosphorylation of cTnI, may slow thin filament activation and result in increased myofilament relaxation kinetics, the latter of which could enhance early phase diastolic relaxation during β-adrenergic stimulation.
Collapse
Affiliation(s)
- Vijay Rao
- University of Washington, Department of Bioengineering, Seattle, Washington
| | - Yuanhua Cheng
- University of Washington, Department of Bioengineering, Seattle, Washington; National Biomedical Computational Resource, La Jolla, California
| | - Steffen Lindert
- University of California San Diego, Department of Pharmacology, La Jolla, California
| | - Dan Wang
- University of Washington, Department of Bioengineering, Seattle, Washington
| | - Lucas Oxenford
- University of Washington, Department of Bioengineering, Seattle, Washington
| | - Andrew D McCulloch
- University of California San Diego, Department of Bioengineering, La Jolla, California; National Biomedical Computational Resource, La Jolla, California
| | - J Andrew McCammon
- University of California San Diego, Department of Pharmacology, La Jolla, California; National Biomedical Computational Resource, La Jolla, California
| | - Michael Regnier
- University of Washington, Department of Bioengineering, Seattle, Washington.
| |
Collapse
|
27
|
Schiaffino S, Rossi AC, Smerdu V, Leinwand LA, Reggiani C. Developmental myosins: expression patterns and functional significance. Skelet Muscle 2015; 5:22. [PMID: 26180627 PMCID: PMC4502549 DOI: 10.1186/s13395-015-0046-6] [Citation(s) in RCA: 307] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 05/27/2015] [Indexed: 11/24/2022] Open
Abstract
Developing skeletal muscles express unique myosin isoforms, including embryonic and neonatal myosin heavy chains, coded by the myosin heavy chain 3 (MYH3) and MYH8 genes, respectively, and myosin light chain 1 embryonic/atrial, encoded by the myosin light chain 4 (MYL4) gene. These myosin isoforms are transiently expressed during embryonic and fetal development and disappear shortly after birth when adult fast and slow myosins become prevalent. However, developmental myosins persist throughout adult stages in specialized muscles, such as the extraocular and jaw-closing muscles, and in the intrafusal fibers of the muscle spindles. These myosins are re-expressed during muscle regeneration and provide a specific marker of regenerating fibers in the pathologic skeletal muscle. Mutations in MYH3 or MYH8 are responsible for distal arthrogryposis syndromes, characterized by congenital joint contractures and orofacial dysmorphisms, supporting the importance of muscle contractile activity and body movements in joint development and in shaping the form of the face during fetal development. The biochemical and biophysical properties of developmental myosins have only partially been defined, and their functional significance is not yet clear. One possibility is that these myosins are specialized in contracting against low loads, and thus, they may be adapted to the prenatal environment, when fetal muscles contract against a very low load compared to postnatal muscles.
Collapse
Affiliation(s)
- Stefano Schiaffino
- Venetian Institute of Molecular Medicine (VIMM), Via G. Orus 2, 35129 Padova, Italy
| | - Alberto C Rossi
- Department of Molecular, Cellular and Developmental Biology and BioFrontiers Institute, University of Colorado, Boulder, CO USA
| | - Vika Smerdu
- Institute of Anatomy, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Leslie A Leinwand
- Department of Molecular, Cellular and Developmental Biology and BioFrontiers Institute, University of Colorado, Boulder, CO USA
| | - Carlo Reggiani
- Department of Biomedical Sciences, University of Padova, Padova, Italy ; CNR Institute of Neuroscience, Padova, Italy
| |
Collapse
|
28
|
Moriyama H, Amano K, Itoh M, Matsumura G, Otsuka N. Morphometric aspects of the facial and skeletal muscles in fetuses. Int J Pediatr Otorhinolaryngol 2015; 79:998-1002. [PMID: 25920965 DOI: 10.1016/j.ijporl.2015.04.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 04/07/2015] [Indexed: 11/29/2022]
Abstract
OBJECTIVES There are few research reports providing a comparison of the muscle fiber morphometry between human fetuses and adults. Data on fetal and adult muscle fibers would be valuable in understanding muscle development and a variety of muscle diseases. This study investigated human muscle fiber growth to clarify the difference between the facial muscles and other skeletal muscles. METHODS The materials were obtained from three male fetuses (6-month-old) and 11 Japanese male cadavers aged 43-86 years (average: 71.8). Human buccinator muscles (facial muscles), masseter and biceps brachii muscles (skeletal muscles) were resected. We counted the muscle fibers and measured their transverse area. We also calculated the number of muscle fibers per mm(2) (NMF) and the average transverse area of the muscle fibers (TAMFs). RESULTS The average of the NMF of the buccinator, masseter and biceps brachii muscles in fetuses had, respectively, 19, 37, and 22 times as many fibers as those in adults. The average fetus/adult ratios of the TAMF of the buccinator, masseter and biceps brachii muscles were 4.0%, 2.4%, 4.1%, respectively. CONCLUSIONS The average NMF for all kinds of muscles decreased after birth; however, the peak in life-span or decreases with the aging process tended to vary with the kind of muscles examined. The average TAMF for all kinds of muscles enlarged after birth. We considered that the enlargement of the TAMF was connected with the emergence of fetal movements and functional demands after birth.
Collapse
Affiliation(s)
- Hiroshi Moriyama
- Department of Anatomy, Showa University School of Medicine, 5-8, Hatanodai 1, Shinagawa-ku, Tokyo 142-8555, Japan.
| | - Kaori Amano
- Department of Anatomy, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611, Japan
| | - Masahiro Itoh
- Department of Anatomy, Tokyo Medical University, 1-1, Shinjuku 6, Shinjuku-ku, Tokyo 160-8402, Japan
| | - George Matsumura
- Department of Anatomy, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611, Japan
| | - Naruhito Otsuka
- Department of Anatomy, Showa University School of Medicine, 5-8, Hatanodai 1, Shinagawa-ku, Tokyo 142-8555, Japan
| |
Collapse
|
29
|
Racca AW, Beck AE, McMillin MJ, Korte FS, Bamshad MJ, Regnier M. The embryonic myosin R672C mutation that underlies Freeman-Sheldon syndrome impairs cross-bridge detachment and cycling in adult skeletal muscle. Hum Mol Genet 2015; 24:3348-58. [PMID: 25740846 DOI: 10.1093/hmg/ddv084] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 03/02/2015] [Indexed: 02/06/2023] Open
Abstract
Distal arthrogryposis is the most common known heritable cause of congenital contractures (e.g. clubfoot) and results from mutations in genes that encode proteins of the contractile complex of skeletal muscle cells. Mutations are most frequently found in MYH3 and are predicted to impair the function of embryonic myosin. We measured the contractile properties of individual skeletal muscle cells and the activation and relaxation kinetics of isolated myofibrils from two adult individuals with an R672C substitution in embryonic myosin and distal arthrogryposis syndrome 2A (DA2A) or Freeman-Sheldon syndrome. In R672C-containing muscle cells, we observed reduced specific force, a prolonged time to relaxation and incomplete relaxation (elevated residual force). In R672C-containing muscle myofibrils, the initial, slower phase of relaxation had a longer duration and slower rate, and time to complete relaxation was greatly prolonged. These observations can be collectively explained by a small subpopulation of myosin cross-bridges with greatly reduced detachment kinetics, resulting in a slower and less complete deactivation of thin filaments at the end of contractions. These findings have important implications for selecting and testing directed therapeutic options for persons with DA2A and perhaps congenital contractures in general.
Collapse
Affiliation(s)
| | - Anita E Beck
- Department of Pediatrics, Seattle Children's Hospital, Seattle, WA 98105, USA
| | | | | | - Michael J Bamshad
- Department of Pediatrics, Department of Genome Sciences, Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Michael Regnier
- Department of Bioengineering, Center for Cardiovascular Biology, University of Washington, Seattle, WA 98195, USA and
| |
Collapse
|
30
|
Moussavi-Harami F, Razumova MV, Racca AW, Cheng Y, Stempien-Otero A, Regnier M. 2-Deoxy adenosine triphosphate improves contraction in human end-stage heart failure. J Mol Cell Cardiol 2015; 79:256-63. [PMID: 25498214 PMCID: PMC4301986 DOI: 10.1016/j.yjmcc.2014.12.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 11/16/2014] [Accepted: 12/02/2014] [Indexed: 01/10/2023]
Abstract
We are developing a novel treatment for heart failure by increasing myocardial 2 deoxy-ATP (dATP). Our studies in rodent models have shown that substitution of dATP for adenosine triphosphate (ATP) as the energy substrate in vitro or elevation of dATP in vivo increases myocardial contraction and that small increases in the native dATP pool of heart muscle are sufficient to improve cardiac function. Here we report, for the first time, the effect of dATP on human adult cardiac muscle contraction. We measured the contractile properties of chemically-demembranated multicellular ventricular wall preparations and isolated myofibrils from human subjects with end-stage heart failure. Isometric force was increased at both saturating and physiologic Ca(2+) concentrations with dATP compared to ATP. This resulted in an increase in the Ca(2+) sensitivity of force (pCa50) by 0.06 pCa units. The rate of force redevelopment (ktr) in demembranated wall muscle was also increased, as was the rate of contractile activation (kACT) in isolated myofibrils, indicating increased cross-bridge binding and cycling compared with ATP in failing human myocardium. These data suggest that dATP could increase dP/dT and end systolic pressure in failing human myocardium. Importantly, even though the magnitude and rate of force development were increased, there was no increase in the time to 50% and 90% myofibril relaxation. These data, along with our previous studies in rodent models, show the promise of elevating myocardial dATP to enhance contraction and restore cardiac pump function. These data also support further pre-clinical evaluation of this new approach for treating heart failure.
Collapse
Affiliation(s)
- Farid Moussavi-Harami
- Division of Cardiology, Department of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Maria V Razumova
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Alice W Racca
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Yuanhua Cheng
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - April Stempien-Otero
- Division of Cardiology, Department of Medicine, University of Washington, Seattle, WA 98195, USA; Center for Cardiovascular Biology, University of Washington, Seattle, WA 98195, USA
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA; Center for Cardiovascular Biology, University of Washington, Seattle, WA 98195, USA; Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|
31
|
Madden L, Juhas M, Kraus WE, Truskey GA, Bursac N. Bioengineered human myobundles mimic clinical responses of skeletal muscle to drugs. eLife 2015; 4:e04885. [PMID: 25575180 PMCID: PMC4337710 DOI: 10.7554/elife.04885] [Citation(s) in RCA: 208] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 01/08/2015] [Indexed: 12/14/2022] Open
Abstract
Existing in vitro models of human skeletal muscle cannot recapitulate the organization and function of native muscle, limiting their use in physiological and pharmacological studies. Here, we demonstrate engineering of electrically and chemically responsive, contractile human muscle tissues (‘myobundles’) using primary myogenic cells. These biomimetic constructs exhibit aligned architecture, multinucleated and striated myofibers, and a Pax7+ cell pool. They contract spontaneously and respond to electrical stimuli with twitch and tetanic contractions. Positive correlation between contractile force and GCaMP6-reported calcium responses enables non-invasive tracking of myobundle function and drug response. During culture, myobundles maintain functional acetylcholine receptors and structurally and functionally mature, evidenced by increased myofiber diameter and improved calcium handling and contractile strength. In response to diversely acting drugs, myobundles undergo dose-dependent hypertrophy or toxic myopathy similar to clinical outcomes. Human myobundles provide an enabling platform for predictive drug and toxicology screening and development of novel therapeutics for muscle-related disorders. DOI:http://dx.doi.org/10.7554/eLife.04885.001 Scientists have developed realistic models of the human liver, lung, and heart that allow them to observe living tissue in the laboratory. These models have helped us to better understand how these organs work and what goes wrong in diseases that affect these organs. The models can also be used to test how new drugs may affect a particular organ without the risk of exposing patients to the drug. Efforts to develop a realistic laboratory model of human muscle tissues that can contract like real muscles have not been as successful to date. This shortcoming has potentially hindered the development of drugs to treat numerous disorders that affect muscles and movement in humans—such as muscular dystrophies, which are diseases in which people progressively lose muscle strength. Some important drugs, like cholesterol-lowering statins, have detrimental effects on muscle tissue; one statin was so harmful to muscles that it had to be withdrawn from the market. As such, it would be useful to have experimental models that would allow scientists to test whether potential drugs damage or treat muscle tissue. Madden et al. have now bioengineered a three-dimensional laboratory model of living muscle tissue made of cells taken from biopsies of several different human patients. These tissues were grown into bundles of muscle fibers on special polymer frames in the laboratory. The bioengineered muscle bundles respond to electrical and chemical signals and contract just like normal muscle. They also exhibit the same structure and signaling as healthy muscle tissue in humans. Madden et al. exposed the muscle tissue bundles to three drugs known to affect muscles to determine if the model could be used to test whether drugs have harmful effects. This revealed that the bundles had weaker contractions in response to statins and the malaria drug chloroquine, just like normal muscles do—and that this effect worsened if more of each drug was used. Madden et al. also found that a drug that strengthens muscle contractions at low doses and damages muscle at high doses in humans has similar effects in the model. As well as this model being used to screen for harmful effects of drugs before clinical trials, the technique used to create the model could be used to grow muscle tissue from patients with muscle diseases. This would help researchers and doctors to better understand the patient's condition and potentially develop more efficient therapies. Also, the technique could be eventually developed to grow healthy muscle tissue to implant in patients who have been injured. DOI:http://dx.doi.org/10.7554/eLife.04885.002
Collapse
Affiliation(s)
- Lauran Madden
- Department of Biomedical Engineering, Duke University, Durham, United States
| | - Mark Juhas
- Department of Biomedical Engineering, Duke University, Durham, United States
| | - William E Kraus
- Department of Medicine, Duke University School of Medicine, Durham, United States
| | - George A Truskey
- Department of Biomedical Engineering, Duke University, Durham, United States
| | - Nenad Bursac
- Department of Biomedical Engineering, Duke University, Durham, United States
| |
Collapse
|
32
|
Abstract
Establishing sufficient skeletal muscle mass is essential for lifelong metabolic health. The intrauterine environment is a major determinant of the muscle mass that is present during the life course of an individual, because muscle fiber number is set at the time of birth. Thus, a compromised intrauterine environment from maternal nutrient restriction or placental insufficiency that restricts muscle fiber number can have permanent effects on the amount of muscle an individual will live with. Reduced muscle mass due to fewer muscle fibers persists even after compensatory or 'catch-up' postnatal growth occurs. Furthermore, muscle hypertrophy can only partially compensate for this limitation in fiber number. Compelling associations link low birth weight and decreased muscle mass to future insulin resistance, which can drive the development of the metabolic syndrome and type 2 diabetes, and the risk of cardiovascular events later in life. There are gaps in knowledge about the origins of reduced muscle growth at the cellular level and how these patterns are set during fetal development. By understanding the nutrient and endocrine regulation of fetal skeletal muscle growth and development, we can direct research efforts toward improving muscle growth early in life to prevent the development of chronic metabolic diseases later in life.
Collapse
Affiliation(s)
- Laura D. Brown
- Department of Pediatrics (Neonatology), University of Colorado School of Medicine, Anschutz Medical Campus F441, Perinatal Research Center, 13243 East 23 Avenue, Aurora, CO 80045, Phone: 303-724-0106, Fax: 303-724-0898
| |
Collapse
|
33
|
Nuclear tropomyosin and troponin in striated muscle: new roles in a new locale? J Muscle Res Cell Motil 2013; 34:275-84. [DOI: 10.1007/s10974-013-9356-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 07/23/2013] [Indexed: 01/03/2023]
|