1
|
Vanegas C, Ursitti J, Kallenbach JG, Pinto K, Harriot A, Coleman AK, Shi G, Ward CW. Acute microtubule changes linked to DMD pathology are insufficient to impair contractile function or enhance contraction-induced injury in healthy muscle. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.19.599775. [PMID: 38948772 PMCID: PMC11212994 DOI: 10.1101/2024.06.19.599775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Duchenne muscular dystrophy (DMD) is marked by the genetic deficiency of the dystrophin protein in striated muscle whose consequence is a cascade of cellular changes that predispose the susceptibility to contraction injury central to DMD pathology. Recent evidence identified the proliferation of microtubules enriched in post-translationally modified tubulin as a consequence of dystrophins absence that increases the passive mechanics of the muscle fiber and the excess mechanotransduction elicited reactive oxygen species and calcium signals that promote contraction injury. Motivated by evidence that acutely normalizing the disease microtubule alterations reduced contraction injury in murine DMD muscle (mdx), here we sought the direct impact of these microtubule alterations independent of dystrophins absence and the multitude of other changes consequent to dystrophic disease. To this end we used acute pharmacologic (epithiolone-D, EpoD; 4 hours) or genetic (vashohibin-2 and small vasohibin binding protein overexpression via AAV9; 2 weeks) strategies to effectively model the proliferation of detyrosination enriched microtubules in the mdx muscle. Quantifying in vivo nerve evoked plantarflexor function we find no alteration in peak torque nor contraction kinetics in WT mice modeling these DMD relevant MT alterations. Quantifying the susceptibility to eccentric contraction injury we show EpoD treatment proffered a small but significant protection from contraction injury while VASH/SVBP had no discernable impact. We conclude that the disease dependent MT alterations act in concert with additional cellular changes to predispose contraction injury in DMD.
Collapse
Affiliation(s)
- Camilo Vanegas
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jeanine Ursitti
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jacob G Kallenbach
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Kaylie Pinto
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Anicca Harriot
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Andrew K Coleman
- Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Guoli Shi
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Christopher W Ward
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, USA
| |
Collapse
|
2
|
Collins BC, Shapiro JB, Scheib MM, Musci RV, Verma M, Kardon G. Three-dimensional imaging studies in mice identify cellular dynamics of skeletal muscle regeneration. Dev Cell 2024; 59:1457-1474.e5. [PMID: 38569550 PMCID: PMC11153043 DOI: 10.1016/j.devcel.2024.03.017] [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: 04/25/2023] [Revised: 12/06/2023] [Accepted: 03/08/2024] [Indexed: 04/05/2024]
Abstract
The function of many organs, including skeletal muscle, depends on their three-dimensional structure. Muscle regeneration therefore requires not only reestablishment of myofibers but also restoration of tissue architecture. Resident muscle stem cells (SCs) are essential for regeneration, but how SCs regenerate muscle architecture is largely unknown. We address this problem using genetic labeling of mouse SCs and whole-mount imaging to reconstruct, in three dimensions, muscle regeneration. Unexpectedly, we found that myofibers form via two distinct phases of fusion and the residual basement membrane of necrotic myofibers is critical for promoting fusion and orienting regenerated myofibers. Furthermore, the centralized myonuclei characteristic of regenerated myofibers are associated with myofibrillogenesis and endure months post injury. Finally, we elucidate two cellular mechanisms for the formation of branched myofibers, a pathology characteristic of diseased muscle. We provide a synthesis of the cellular events of regeneration and show that these differ from those used during development.
Collapse
Affiliation(s)
- Brittany C Collins
- Department of Human Genetics, University of Utah, Salt Lake City, UT, USA
| | - Jacob B Shapiro
- Department of Human Genetics, University of Utah, Salt Lake City, UT, USA
| | - Mya M Scheib
- Department of Human Genetics, University of Utah, Salt Lake City, UT, USA
| | - Robert V Musci
- Department of Human Genetics, University of Utah, Salt Lake City, UT, USA
| | - Mayank Verma
- Department of Pediatrics, Division of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Gabrielle Kardon
- Department of Human Genetics, University of Utah, Salt Lake City, UT, USA.
| |
Collapse
|
3
|
Haug M, Schwappacher R, Pollmann C, Ritter P, Michael M, Hermann HJ, Grützmann R, Mittelstädt A, Neurath MF, Zopf Y, Friedrich O. Effects of Adjuvant Exercise and Nutrition Therapy on Muscle Fibre Biomechanics in Gastrointestinal Cancer Patients. Cancers (Basel) 2024; 16:1608. [PMID: 38672689 PMCID: PMC11049604 DOI: 10.3390/cancers16081608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 04/17/2024] [Accepted: 04/18/2024] [Indexed: 04/28/2024] Open
Abstract
Patients with aggressive cancer, e.g., gastrointestinal cancer, are prone (≥50% chance) to developing cancer cachexia (CC). Little is known about the effects of CC on the biomechanical function of muscle. A promising prevention strategy was found in the form of a multi-modal therapy combining mild resistance exercise (e.g., whole-body electro-myostimulation, WB-EMS) and a protein-rich diet. In a previous study of ours, this was effective in counteracting the loss of muscle mass, yet a systematic and comprehensive assessment of active and passive single muscle fibre functions was so far absent. This pilot study investigated the biomechanical function of single muscle fibres (rectus abdominis) from the biopsies of conventionally treated (pre-)cachectic cancer ((pre-)CC) patients (m = 9), those receiving the multi-modal therapy comprising WB-EMS training and protein-rich nutrition (m = 3), and a control group (m = 5). Our findings not only align with previous findings showing the absolute force loss in CC that is accelerated by atrophy but also speak in favour of a different, potentially energy- and Ca2+-homeostasis-related effect that compromises muscle contraction (F ~0.9 mN vs. F ~0.6 mN in control patients). However, myofibrillar Ca2+ sensitivity and the quality of contraction were unaltered (pCa50: 5.6-5.8). Single fibres from the (pre-)CC patients receiving WB-EMS training and protein supplementation were significantly more compliant (p < 0.001 at ≥130% of resting length L0). Those fibres displayed a similar softness to the ones from the control patients (axial compliance ~15 m/N at ≥130% L0), while single fibres from the patients with (developing) cachexia were significantly stiffer (axial compliance ~7 m/N, p < 0.001 at ≥130% L0). Adjuvant multi-modal therapy (WB-EMS training and nutritional support) contributes to maintaining the axial compliance of single fibres and potentially improves the quality of life for patients at risk of developing CC.
Collapse
Affiliation(s)
- Michael Haug
- Institute of Medical Biotechnology (MBT), Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany; (C.P.); (P.R.); (M.M.); (O.F.)
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 6, 91052 Erlangen, Germany
| | - Raphaela Schwappacher
- Hector-Centre for Nutrition, Exercise and Sports, Medical Department 1, Friedrich-Alexander-University Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany; (R.S.); (H.J.H.); (Y.Z.)
- Medical Department 1, Friedrich-Alexander-University Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany;
| | - Charlotte Pollmann
- Institute of Medical Biotechnology (MBT), Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany; (C.P.); (P.R.); (M.M.); (O.F.)
| | - Paul Ritter
- Institute of Medical Biotechnology (MBT), Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany; (C.P.); (P.R.); (M.M.); (O.F.)
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 6, 91052 Erlangen, Germany
| | - Mena Michael
- Institute of Medical Biotechnology (MBT), Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany; (C.P.); (P.R.); (M.M.); (O.F.)
- Medical Department 1, Friedrich-Alexander-University Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany;
| | - Hans Joachim Hermann
- Hector-Centre for Nutrition, Exercise and Sports, Medical Department 1, Friedrich-Alexander-University Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany; (R.S.); (H.J.H.); (Y.Z.)
- Medical Department 1, Friedrich-Alexander-University Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany;
| | - Robert Grützmann
- Department of General and Visceral Surgery, Friedrich-Alexander-University Erlangen-Nürnberg, Krankenhausstr. 12, 91054 Erlangen, Germany; (R.G.); (A.M.)
| | - Anke Mittelstädt
- Department of General and Visceral Surgery, Friedrich-Alexander-University Erlangen-Nürnberg, Krankenhausstr. 12, 91054 Erlangen, Germany; (R.G.); (A.M.)
| | - Markus Friedrich Neurath
- Medical Department 1, Friedrich-Alexander-University Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany;
| | - Yurdagül Zopf
- Hector-Centre for Nutrition, Exercise and Sports, Medical Department 1, Friedrich-Alexander-University Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany; (R.S.); (H.J.H.); (Y.Z.)
- Medical Department 1, Friedrich-Alexander-University Erlangen-Nürnberg, Ulmenweg 18, 91054 Erlangen, Germany;
| | - Oliver Friedrich
- Institute of Medical Biotechnology (MBT), Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany; (C.P.); (P.R.); (M.M.); (O.F.)
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 6, 91052 Erlangen, Germany
- School of Biomedical Sciences, University of New South Wales, Wallace Wurth Building, 18 High St, Sydney, NSW 2052, Australia
| |
Collapse
|
4
|
Riddell DO, Hildyard JCW, Harron RCM, Taylor-Brown F, Kornegay JN, Wells DJ, Piercy RJ. Longitudinal assessment of skeletal muscle functional mechanics in the DE50-MD dog model of Duchenne muscular dystrophy. Dis Model Mech 2023; 16:dmm050395. [PMID: 38050706 PMCID: PMC10753191 DOI: 10.1242/dmm.050395] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 11/29/2023] [Indexed: 12/06/2023] Open
Abstract
Duchenne muscular dystrophy (DMD), caused by mutations in the dystrophin (DMD) gene, is associated with fatal muscle degeneration and atrophy. Patients with DMD have progressive reductions in skeletal muscle strength and resistance to eccentric muscle stretch. Using the DE50-MD dog model of DMD, we assessed tibiotarsal joint (TTJ) flexor and extensor force dynamics, and the resistance of dystrophic muscle to eccentric stretch. Male DE50-MD and wild-type (WT) dogs were analysed every 3 months until 18 months of age. There was an age-associated decline in eccentric contraction resistance in DE50-MD TTJ flexors that discriminated, with high statistical power, WT from DE50-MD individuals. For isometric contraction, at the majority of timepoints, DE50-MD dogs had lower maximum absolute and relative TTJ flexor force, reduced TTJ muscle contraction times and prolonged relaxation compared to those in WT dogs. Cranial tibial muscles, the primary TTJ flexor, of 18-month-old DE50-MD dogs had significant numbers of regenerating fibres as expected, but also fewer type I fibres and more hybrid fibres than those in WT dogs. We conclude that these parameters, in particular, the eccentric contraction decrement, could be used as objective outcome measures for pre-clinical assessment in DE50-MD dogs.
Collapse
Affiliation(s)
- Dominique O. Riddell
- Comparative Neuromuscular Diseases Laboratory, Department of Clinical Science and Services, Royal Veterinary College, London NW10TU, UK
| | - John C. W. Hildyard
- Comparative Neuromuscular Diseases Laboratory, Department of Clinical Science and Services, Royal Veterinary College, London NW10TU, UK
| | - Rachel C. M. Harron
- Comparative Neuromuscular Diseases Laboratory, Department of Clinical Science and Services, Royal Veterinary College, London NW10TU, UK
| | - Frances Taylor-Brown
- Comparative Neuromuscular Diseases Laboratory, Department of Clinical Science and Services, Royal Veterinary College, London NW10TU, UK
| | - Joe N. Kornegay
- Texas A&M University, College of Veterinary Medicine and Biomedical Sciences, College Station, TX 77843, USA
| | - Dominic J. Wells
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London NW10TU, UK
| | - Richard J. Piercy
- Comparative Neuromuscular Diseases Laboratory, Department of Clinical Science and Services, Royal Veterinary College, London NW10TU, UK
| |
Collapse
|
5
|
Harriot AD, Altair Morris T, Vanegas C, Kallenbach J, Pinto K, Joca HC, Moutin MJ, Shi G, Ursitti JA, Grosberg A, Ward CW. Detyrosinated microtubule arrays drive myofibrillar malformations in mdx muscle fibers. Front Cell Dev Biol 2023; 11:1209542. [PMID: 37691825 PMCID: PMC10485621 DOI: 10.3389/fcell.2023.1209542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 08/09/2023] [Indexed: 09/12/2023] Open
Abstract
Altered myofibrillar structure is a consequence of dystrophic pathology that impairs skeletal muscle contractile function and increases susceptibility to contraction injury. In murine Duchenne muscular dystrophy (mdx), myofibrillar alterations are abundant in advanced pathology (>4 months), an age where we formerly established densified microtubule (MT) arrays enriched in detyrosinated (deTyr) tubulin as negative disease modifiers impacting cell mechanics and mechanotransduction. Given the essential role of deTyr-enriched MT arrays in myofibrillar growth, maintenance, and repair, we examined the increased abundance of these arrays as a potential mechanism for these myofibrillar alterations. Here we find an increase in deTyr-tubulin as an early event in dystrophic pathology (4 weeks) with no evidence myofibrillar alterations. At 16 weeks, we show deTyr-enriched MT arrays significantly densified and co-localized to areas of myofibrillar malformation. Profiling the enzyme complexes responsible for deTyr-tubulin, we identify vasohibin 2 (VASH2) and small vasohibin binding protein (SVBP) significantly elevated in the mdx muscle at 4 weeks. Using the genetic increase in VASH2/SVBP expression in 4 weeks wild-type mice we find densified deTyr-enriched MT arrays that co-segregate with myofibrillar malformations similar to those in the 16 weeks mdx. Given that no changes in sarcomere organization were identified in fibers expressing sfGFP as a control, we conclude that disease-dependent densification of deTyr-enriched MT arrays underscores the altered myofibrillar structure in dystrophic skeletal muscle fibers.
Collapse
Affiliation(s)
- Anicca D. Harriot
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Tessa Altair Morris
- Center for Complex Biological Systems, Edwards Lifesciences Foundation Cardiovascular Innovation and Research Center, and the NSF-Simons Center for Multiscale Cell Fate Research, University of California, Irvine, Irvine, CA, United States
| | - Camilo Vanegas
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Jacob Kallenbach
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Kaylie Pinto
- Department of Molecular Medicine, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Humberto C. Joca
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Marie-Jo Moutin
- INSERM U1216 Centre National de la Recherche Scientifique, Grenoble Institut Neurosciences, University Grenoble Alpes, Grenoble, France
| | - Guoli Shi
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Jeanine A. Ursitti
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Anna Grosberg
- Center for Complex Biological Systems, Edwards Lifesciences Foundation Cardiovascular Innovation and Research Center, and the NSF-Simons Center for Multiscale Cell Fate Research, University of California, Irvine, Irvine, CA, United States
- Department of Biomedical Engineering, Sue and Bill Gross Stem Cell Research, University of California, Irvine, Irvine, CA, United States
- Department of Chemical and Biomolecular Engineering, Sue and Bill Gross Stem Cell Research, University of California, Irvine, Irvine, CA, United States
| | - Christopher W. Ward
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, United States
| |
Collapse
|
6
|
Lloyd EM, Pinniger GJ, Murphy RM, Grounds MD. Slow or fast: Implications of myofibre type and associated differences for manifestation of neuromuscular disorders. Acta Physiol (Oxf) 2023; 238:e14012. [PMID: 37306196 DOI: 10.1111/apha.14012] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 05/30/2023] [Accepted: 06/06/2023] [Indexed: 06/13/2023]
Abstract
Many neuromuscular disorders can have a differential impact on a specific myofibre type, forming the central premise of this review. The many different skeletal muscles in mammals contain a spectrum of slow- to fast-twitch myofibres with varying levels of protein isoforms that determine their distinctive contractile, metabolic, and other properties. The variations in functional properties across the range of classic 'slow' to 'fast' myofibres are outlined, combined with exemplars of the predominantly slow-twitch soleus and fast-twitch extensor digitorum longus muscles, species comparisons, and techniques used to study these properties. Other intrinsic and extrinsic differences are discussed in the context of slow and fast myofibres. These include inherent susceptibility to damage, myonecrosis, and regeneration, plus extrinsic nerves, extracellular matrix, and vasculature, examined in the context of growth, ageing, metabolic syndrome, and sexual dimorphism. These many differences emphasise the importance of carefully considering the influence of myofibre-type composition on manifestation of various neuromuscular disorders across the lifespan for both sexes. Equally, understanding the different responses of slow and fast myofibres due to intrinsic and extrinsic factors can provide deep insight into the precise molecular mechanisms that initiate and exacerbate various neuromuscular disorders. This focus on the influence of different myofibre types is of fundamental importance to enhance translation for clinical management and therapies for many skeletal muscle disorders.
Collapse
Affiliation(s)
- Erin M Lloyd
- Department of Anatomy, Physiology and Human Biology, School of Human Sciences, The University of Western Australia, Perth, Western Australia, Australia
- Curtin Health Innovation Research Institute, Curtin Medical School, Curtin University, Bentley, Western Australia, Australia
| | - Gavin J Pinniger
- Department of Anatomy, Physiology and Human Biology, School of Human Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Robyn M Murphy
- Department of Biochemistry and Chemistry, School of Agriculture, Biomedicine and Environment, La Trobe University, Melbourne, Victoria, Australia
| | - Miranda D Grounds
- Department of Anatomy, Physiology and Human Biology, School of Human Sciences, The University of Western Australia, Perth, Western Australia, Australia
| |
Collapse
|
7
|
Wasala LP, Watkins TB, Wasala NB, Burke MJ, Yue Y, Lai Y, Yao G, Duan D. The Implication of Hinge 1 and Hinge 4 in Micro-Dystrophin Gene Therapy for Duchenne Muscular Dystrophy. Hum Gene Ther 2023; 34:459-470. [PMID: 36310439 PMCID: PMC10210230 DOI: 10.1089/hum.2022.180] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 10/15/2022] [Indexed: 11/04/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a fatal muscle disease caused by dystrophin deficiency. Dystrophin consists of the amino terminus, central rod domain with 24 spectrin-like repeats and four hinges (H), cysteine-rich domain, and carboxyl terminus. Several highly abbreviated micro-dystrophins (μDys) are currently in clinical trials. They all carry H1 and H4. In this study, we investigated whether these two hinges are essential for μDy function in murine DMD models. Three otherwise identical μDys were engineered to contain H1 and/or H4 and were named H1/H4 (with both H1 and H4), ΔH1 (without H1), and ΔH4 (without H4). These constructs were packaged in adeno-associated virus serotype-9 and delivered to the tibialis anterior muscle of 3-month-old male mdx4cv mice (1E12 vector genome particles/muscle). Three months later, we detected equivalent μDys expression in total muscle lysate. However, only H1/H4 and ΔH1 showed correct sarcolemmal localization. ΔH4 mainly existed as sarcoplasmic aggregates. H1/H4 and ΔH1, but not ΔH4, fully restored the dystrophin-associated protein complex and significantly improved the specific muscle force. Eccentric contraction-induced force decline was best protected by H1/H4, followed by ΔH1, but not by ΔH4. Next, we compared H1/H4 and ΔH1 in 6-week-old male mdx mice by intravenous injection (1E13 vector genome particles/mouse). Four months postinjection, H1/H4 significantly outperformed ΔH1 in extensor digitorum longus muscle force measurements but two constructs yielded comparable electrocardiography improvements. We conclude that H4 is essential for μDys function and H1 facilitates force production. Our findings will help develop next-generation μDys gene therapy.
Collapse
Affiliation(s)
- Lakmini P. Wasala
- Department of Veterinary Pathobiology, College of Veterinary Medicine, The University of Missouri, Columbia, Missouri, USA
| | - Thais B. Watkins
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, Missouri, USA
| | - Nalinda B. Wasala
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, Missouri, USA
| | - Matthew J. Burke
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, Missouri, USA
| | - Yongping Yue
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, Missouri, USA
| | - Yi Lai
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, Missouri, USA
| | - Gang Yao
- Department of Chemical and Biomedical Engineering, College of Engineering, The University of Missouri, Columbia, Missouri, USA
| | - Dongsheng Duan
- Department of Veterinary Pathobiology, College of Veterinary Medicine, The University of Missouri, Columbia, Missouri, USA
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, Missouri, USA
- Department of Chemical and Biomedical Engineering, College of Engineering, The University of Missouri, Columbia, Missouri, USA
- Department of Neurology, School of Medicine, The University of Missouri, Columbia, Missouri, USA
- Department of Biomedical Sciences, College of Veterinary Medicine; The University of Missouri, Columbia, Missouri, USA
| |
Collapse
|
8
|
Dubuisson N, Davis-López de Carrizosa MA, Versele R, Selvais CM, Noel L, Van den Bergh PYD, Brichard SM, Abou-Samra M. Inhibiting the inflammasome with MCC950 counteracts muscle pyroptosis and improves Duchenne muscular dystrophy. Front Immunol 2022; 13:1049076. [PMID: 36569900 PMCID: PMC9770793 DOI: 10.3389/fimmu.2022.1049076] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 11/23/2022] [Indexed: 12/12/2022] Open
Abstract
Background Duchenne muscular dystrophy (DMD) is the most common inherited human myopathy. Typically, the secondary process involving severe inflammation and necrosis exacerbate disease progression. Previously, we reported that the NLRP3 inflammasome complex plays a crucial role in this disorder. Moreover, pyroptosis, a form of programmed necrotic cell death, is triggered by NLRP3 via gasdermin D (GSDMD). So far, pyroptosis has never been described either in healthy muscle or in dystrophic muscle. The aim of this study was to unravel the role of NLRP3 inflammasome in DMD and explore a potentially promising treatment with MCC950 that selectively inhibits NLRP3. Methods Four-week-old mdx mice (n=6 per group) were orally treated for 2 months with MCC950 (mdx-T), a highly potent, specific, small-molecule inhibitor of NLRP3, and compared with untreated (mdx) and wild-type (WT) mice. In vivo functional tests were carried out to measure the global force and endurance of mice. Ex vivo biochemical and molecular analyses were performed to evaluate the pathophysiology of the skeletal muscle. Finally, in vitro tests were conducted on primary cultures of DMD human myotubes. Results After MCC950 treatment, mdx mice exhibited a significant reduction of inflammation, macrophage infiltration and oxidative stress (-20 to -65%, P<0.05 vs untreated mdx). Mdx-T mice displayed considerably less myonecrosis (-54%, P<0.05 vs mdx) and fibrosis (-75%, P<0.01 vs mdx). Moreover, a more mature myofibre phenotype, characterized by larger-sized fibres and higher expression of mature myosin heavy chains 1 and 7 was observed. Mdx-T also exhibited enhanced force and resistance to fatigue (+20 to 60%, P<0.05 or less). These beneficial effects resulted from MCC950 inhibition of both active caspase-1 (-46%, P=0.075) and cleaved gasdermin D (N-GSDMD) (-42% in medium-sized-fibres, P<0.001). Finally, the anti-inflammatory action and the anti-pyroptotic effect of MCC950 were also recapitulated in DMD human myotubes. Conclusion Specific inhibition of the NLRP3 inflammasome can significantly attenuate the dystrophic phenotype. A novel finding of this study is the overactivation of GSDMD, which is hampered by MCC950. This ultimately leads to less inflammation and pyroptosis and to a better muscle maturation and function. Targeting NLRP3 might lead to an effective therapeutic approach for a better management of DMD.
Collapse
Affiliation(s)
- Nicolas Dubuisson
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research (IREC), Medical Sector, Université Catholique de Louvain (UCLouvain), Brussels, Belgium,Neuromuscular Reference Center, Department of Neurology, Cliniques Universitaires Saint-Luc, Brussels, Belgium,*Correspondence: Nicolas Dubuisson,
| | - María A. Davis-López de Carrizosa
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research (IREC), Medical Sector, Université Catholique de Louvain (UCLouvain), Brussels, Belgium,Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, Sevilla, Spain
| | - Romain Versele
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research (IREC), Medical Sector, Université Catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Camille M. Selvais
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research (IREC), Medical Sector, Université Catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Laurence Noel
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research (IREC), Medical Sector, Université Catholique de Louvain (UCLouvain), Brussels, Belgium
| | - P. Y. D. Van den Bergh
- Neuromuscular Reference Center, Department of Neurology, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | - Sonia M. Brichard
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research (IREC), Medical Sector, Université Catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Michel Abou-Samra
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research (IREC), Medical Sector, Université Catholique de Louvain (UCLouvain), Brussels, Belgium
| |
Collapse
|
9
|
Ritter P, Nübler S, Buttgereit A, Smith LR, Mühlberg A, Bauer J, Michael M, Kreiß L, Haug M, Barton E, Friedrich O. Myofibrillar Lattice Remodeling Is a Structural Cytoskeletal Predictor of Diaphragm Muscle Weakness in a Fibrotic mdx ( mdx Cmah-/-) Model. Int J Mol Sci 2022; 23:ijms231810841. [PMID: 36142754 PMCID: PMC9500669 DOI: 10.3390/ijms231810841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 11/24/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a degenerative genetic myopathy characterized by complete absence of dystrophin. Although the mdx mouse lacks dystrophin, its phenotype is milder compared to DMD patients. The incorporation of a null mutation in the Cmah gene led to a more DMD-like phenotype (i.e., more fibrosis). Although fibrosis is thought to be the major determinant of ‘structural weakness’, intracellular remodeling of myofibrillar geometry was shown to be a major cellular determinant thereof. To dissect the respective contribution to muscle weakness, we assessed biomechanics and extra- and intracellular architecture of whole muscle and single fibers from extensor digitorum longus (EDL) and diaphragm. Despite increased collagen contents in both muscles, passive stiffness in mdx Cmah−/− diaphragm was similar to wt mice (EDL muscles were twice as stiff). Isometric twitch and tetanic stresses were 50% reduced in mdx Cmah−/− diaphragm (15% in EDL). Myofibrillar architecture was severely compromised in mdx Cmah−/− single fibers of both muscle types, but more pronounced in diaphragm. Our results show that the mdx Cmah−/− genotype reproduces DMD-like fibrosis but is not associated with changes in passive visco-elastic muscle stiffness. Furthermore, detriments in active isometric force are compatible with the pronounced myofibrillar disarray of the dystrophic background.
Collapse
Affiliation(s)
- Paul Ritter
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- Correspondence:
| | - Stefanie Nübler
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Andreas Buttgereit
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Lucas R. Smith
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, CA 95618, USA
| | - Alexander Mühlberg
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Julian Bauer
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Mena Michael
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Lucas Kreiß
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Michael Haug
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Elisabeth Barton
- College of Health & Human Performance, University of Florida, Gainesville, FL 32611, USA
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Department of Chemical and Biological Engineering, Friedrich-Alexander-University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- School of Medical Sciences, University of New South Wales, Wallace Wurth Building, 18 High Str., Sydney, NSW 2052, Australia
| |
Collapse
|
10
|
García-Castañeda M, Michelucci A, Zhao N, Malik S, Dirksen RT. Postdevelopmental knockout of Orai1 improves muscle pathology in a mouse model of Duchenne muscular dystrophy. J Gen Physiol 2022; 154:213383. [PMID: 35939054 PMCID: PMC9365874 DOI: 10.1085/jgp.202213081] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 07/07/2022] [Indexed: 11/20/2022] Open
Abstract
Duchenne muscular dystrophy (DMD), an X-linked disorder caused by loss-of-function mutations in the dystrophin gene, is characterized by progressive muscle degeneration and weakness. Enhanced store-operated Ca2+ entry (SOCE), a Ca2+ influx mechanism coordinated by STIM1 sensors of luminal Ca2+ within the sarcoplasmic reticulum (SR) and Ca2+-permeable Orai1 channels in the sarcolemma, is proposed to contribute to Ca2+-mediated muscle damage in DMD. To directly determine the impact of Orai1-dependent SOCE on the dystrophic phenotype, we crossed mdx mice with tamoxifen-inducible, muscle-specific Orai1 knockout mice (mdx-Orai1 KO mice). Both constitutive and SOCE were significantly increased in flexor digitorum brevis fibers from mdx mice, while SOCE was absent in fibers from both Orai1 KO and mdx-Orai1 KO mice. Compared with WT mice, fibers from mdx mice exhibited (1) increased resting myoplasmic Ca2+ levels, (2) reduced total releasable Ca2+ store content, and (3) a prolonged rate of electrically evoked Ca2+ transient decay. These effects were partially normalized in fibers from mdx-Orai1 KO mice. Intact extensor digitorum longus muscles from mdx mice exhibited a significant reduction of maximal specific force, which was rescued in muscles from mdx-Orai1 KO mice. Finally, during exposure to consecutive eccentric contractions, muscles from mdx mice displayed a more pronounced decline in specific force compared with that of WT mice, which was also significantly attenuated by Orai1 ablation. Together, these results indicate that enhanced Orai1-dependent SOCE exacerbates the dystrophic phenotype and that Orai1 deficiency improves muscle pathology by both normalizing Ca2+ homeostasis and promoting sarcolemmal integrity/stability.
Collapse
Affiliation(s)
- Maricela García-Castañeda
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, NY
| | - Antonio Michelucci
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, NY,Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Nan Zhao
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, NY
| | - Sundeep Malik
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, NY
| | - Robert T. Dirksen
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, NY
| |
Collapse
|
11
|
Ashida Y, Himori K, Tokuda N, Naito A, Yamauchi N, Takenaka-Ninagawa N, Aoki Y, Sakurai H, Yamada T. Dissociation of SH3 and cysteine rich domain 3 and junctophilin 1 from dihydropyridine receptor in dystrophin-deficient muscles. Am J Physiol Cell Physiol 2022; 323:C885-C895. [PMID: 35912995 DOI: 10.1152/ajpcell.00163.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The disruption of excitation-contraction (EC) coupling and subsequent reduction in Ca2+ release from the sarcoplasmic reticulum (SR) have been shown to account for muscle weakness seen in patients with Duchenne muscular dystrophy (DMD). Here, we examined the mechanisms underlying EC uncoupling in skeletal muscles from mdx52 and DMD-null/NSG mice, animal models for DMD, focusing on the SH3 and cysteine rich domain 3 (STAC3) and junctophilin 1 (JP1), which link the dihydropyridine receptor (DHPR) in the transverse tubule and the ryanodine receptor 1 in the SR. The isometric plantarflexion torque normalized to muscle weight of whole plantar flexor muscles was depressed in mdx52 and DMD-null/NSG mice compared to their control mice. This was accompanied by increased autolysis of calpain-1, decreased levels of STAC3 and JP1 content, and dissociation of STAC3 and JP1 from DHPR-α1s in gastrocnemius muscles. Moreover, in vitro mechanistic experiments demonstrated that STAC3 and JP1 underwent Ca2+-dependent proteolysis which was less pronounced in dystrophin-deficient muscles where calpastatin, the endogenous calpain inhibitor, was upregulated. Eccentric contractions further enhanced autolysis of calpain-1 and proteolysis of STAC3 and JP1 that were associated with severe torque depression in gastrocnemius muscles from DMD-null/NSG mice. These data suggest that Ca2+-dependent proteolysis of STAC3 and JP1 may be an essential factor causing muscle weakness due to EC coupling failure in dystrophin-deficient muscles.
Collapse
Affiliation(s)
- Yuki Ashida
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan.,Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
| | - Koichi Himori
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan.,Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
| | - Nao Tokuda
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Azuma Naito
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | - Nao Yamauchi
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| | | | - Yoshitsugu Aoki
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Hidetoshi Sakurai
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan
| | - Takashi Yamada
- Graduate School of Health Sciences, Sapporo Medical University, Sapporo, Japan
| |
Collapse
|
12
|
Kiriaev L, Houweling PJ, North KN, Head SI. Loss of α-actinin-3 confers protection from eccentric contraction damage in fast-twitch EDL muscles from aged mdx dystrophic mice by reducing pathological fibre branching. Hum Mol Genet 2022; 31:1417-1429. [PMID: 34761268 PMCID: PMC9071495 DOI: 10.1093/hmg/ddab326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/27/2021] [Accepted: 11/02/2021] [Indexed: 11/14/2022] Open
Abstract
The common null polymorphism (R577X) in the ACTN3 gene is present in over 1.5 billion people worldwide and results in the absence of the protein α-actinin-3 from the Z-discs of fast-twitch skeletal muscle fibres. We have previously reported that this polymorphism is a modifier of dystrophin-deficient Duchenne Muscular Dystrophy. To investigate the mechanism underlying this, we use a double knockout (dk)Actn3KO/mdx (dKO) mouse model, which lacks both dystrophin and sarcomere α-actinin-3. We used dKO mice and mdx dystrophic mice at 12 months (aged) to investigate the correlation between morphological changes to the fast-twitch dKO EDL and the reduction in force deficit produced by an in vitro eccentric contraction protocol. In the aged dKO mouse, we found a marked reduction in fibre branching complexity that correlated with protection from eccentric contraction induced force deficit. Complex branches in the aged dKO EDL fibres (28%) were substantially reduced compared to aged mdx EDL fibres (68%), and this correlates with a graded force loss over three eccentric contractions for dKO muscles (~36% after first contraction, ~66% overall) compared to an abrupt drop in mdx upon the first eccentric contraction (~75% after first contraction, ~89% after three contractions). In dKO, protection from eccentric contraction damage was linked with a doubling of SERCA1 pump density the EDL. We propose that the increased oxidative metabolism of fast-twitch glycolytic fibres characteristic of the null polymorphism (R577X) and increase in SR Ca2+ pump proteins reduces muscle fibre branching and decreases susceptibility to eccentric injury in the dystrophinopathies.
Collapse
Affiliation(s)
- Leonit Kiriaev
- School of Medicine, Western Sydney University, Sydney, NSW 2560, Australia
| | - Peter J Houweling
- Murdoch Children’s Research Institute, Melbourne, Victoria 3052, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Kathryn N North
- Murdoch Children’s Research Institute, Melbourne, Victoria 3052, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Stewart I Head
- School of Medicine, Western Sydney University, Sydney, NSW 2560, Australia
- Murdoch Children’s Research Institute, Melbourne, Victoria 3052, Australia
| |
Collapse
|
13
|
Chan S, Kueh SLL, Morley JW, Head SI. Sarcoplasmic reticulum calcium handling in unbranched, immediately post-necrotic fast-twitch mdx fibres is similar to wild-type littermates. Exp Physiol 2022; 107:601-614. [PMID: 35471703 DOI: 10.1113/ep090057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 04/19/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS Central question: What are the early effects of dystrophin deficiency on SR Ca2+ handling in the mdx mouse? MAIN FINDING In the mdx mouse, Ca2+ handling by the SR is little affected by the absence of dystrophin when looking at fibres without branches that have just regenerated following massive myonecrosis. This has important implications for our understanding of Ca2+ pathology in the mdx mouse. ABSTRACT There is a variety of results in the literature regarding the effects of dystrophin deficiency on the Ca2+ -handling properties of the SR in mdx mice, an animal model of Duchenne muscular dystrophy. One possible source of variation is the presence of branched fibres. Fibre branching, a consequence of degenerative-regenerative processes such as muscular dystrophy, has in itself a significant influence on the function of the SR. In our present study we attempt to detect early effects of dystrophin deficiency on SR Ca2+ handling by using unbranched fibres from the immediate post-necrotic stage in mdx mice (just regenerated following massive necrosis). Using kinetically-corrected Fura-2 fluorescence signals measured during twitch and tetanus, we analysed the amplitude, rise time and decay time of Δ[Ca2+ ]i in unfatigued and fatigued fibres. Decay was also resolved into SR pump and SR leak components. Fibres from mdx mice were similar in all respects to fibres from wt littermates apart from: (i) a smaller amplitude of the initial spike of Δ[Ca2+ ]i during a tetanus; and (ii) a mitigation of the fall in Δ[Ca2+ ]i amplitude during the course of fatigue. Our findings suggest that the early effects of a loss of dystrophin on SR Ca2+ handling in mdx mice are subtle, and emphasise the importance of distinguishing between Ca2+ pathology that is due to lack of dystrophin and Ca2+ pathology that is due to muscle degeneration. This article is protected by copyright. All rights reserved.
Collapse
Affiliation(s)
- Stephen Chan
- School of Medicine, Western Sydney University, Campbelltown, New South Wales, Australia.,Department of Physiology, Faculty of Science, Mahidol University, Ratchatewi, Bangkok, Thailand
| | - Sindy L L Kueh
- School of Medicine, Western Sydney University, Campbelltown, New South Wales, Australia
| | - John W Morley
- School of Medicine, Western Sydney University, Campbelltown, New South Wales, Australia
| | - Stewart I Head
- School of Medicine, Western Sydney University, Campbelltown, New South Wales, Australia
| |
Collapse
|
14
|
Kiriaev L, Kueh S, Morley JW, North KN, Houweling PJ, Head SI. Lifespan Analysis of Dystrophic mdx Fast-Twitch Muscle Morphology and Its Impact on Contractile Function. Front Physiol 2021; 12:771499. [PMID: 34950049 PMCID: PMC8689589 DOI: 10.3389/fphys.2021.771499] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 11/08/2021] [Indexed: 11/13/2022] Open
Abstract
Duchenne muscular dystrophy is caused by the absence of the protein dystrophin from skeletal muscle and is characterized by progressive cycles of necrosis/regeneration. Using the dystrophin deficient mdx mouse model, we studied the morphological and contractile chronology of dystrophic skeletal muscle pathology in fast-twitch Extensor Digitorum Longus muscles from animals 4–22 months of age containing 100% regenerated muscle fibers. Catastrophically, the older age groups lost ∼80% of their maximum force after one eccentric contraction (EC) of 20% strain with the greatest loss of ∼92% recorded in senescent 22-month-old mdx mice. In old age groups, there was minimal force recovery ∼24% after 120 min, correlated with a dramatic increase in the number and complexity of branched fibers. This data supports our two-phase model where a “tipping point” is reached when branched fibers rupture irrevocably on EC. These findings have important implications for pre-clinical drug studies and genetic rescue strategies.
Collapse
Affiliation(s)
- Leonit Kiriaev
- Myogenica Laboratory, School of Medicine, Western Sydney University, Sydney, NSW, Australia
- *Correspondence: Leonit Kiriaev,
| | - Sindy Kueh
- Myogenica Laboratory, School of Medicine, Western Sydney University, Sydney, NSW, Australia
| | - John W. Morley
- Myogenica Laboratory, School of Medicine, Western Sydney University, Sydney, NSW, Australia
| | - Kathryn N. North
- Muscle Research Group, Murdoch Children’s Research Institute, Melbourne, VIC, Australia
| | - Peter J. Houweling
- Muscle Research Group, Murdoch Children’s Research Institute, Melbourne, VIC, Australia
| | - Stewart I. Head
- Myogenica Laboratory, School of Medicine, Western Sydney University, Sydney, NSW, Australia
- Muscle Research Group, Murdoch Children’s Research Institute, Melbourne, VIC, Australia
| |
Collapse
|
15
|
Baumann CW, Lindsay A, Sidky SR, Ervasti JM, Warren GL, Lowe DA. Contraction-Induced Loss of Plasmalemmal Electrophysiological Function Is Dependent on the Dystrophin Glycoprotein Complex. Front Physiol 2021; 12:757121. [PMID: 34764884 PMCID: PMC8576390 DOI: 10.3389/fphys.2021.757121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/05/2021] [Indexed: 02/03/2023] Open
Abstract
Weakness and atrophy are key features of Duchenne muscular dystrophy (DMD). Dystrophin is one of the many proteins within the dystrophin glycoprotein complex (DGC) that maintains plasmalemmal integrity and cellular homeostasis. The dystrophin-deficient mdx mouse is also predisposed to weakness, particularly when subjected to eccentric (ECC) contractions due to electrophysiological dysfunction of the plasmalemma. Here, we determined if maintenance of plasmalemmal excitability during and after a bout of ECC contractions is dependent on intact and functional DGCs rather than, solely, dystrophin expression. Wild-type (WT) and dystrophic mice (mdx, mL172H and Sgcb-/- mimicking Duchenne, Becker and Limb-girdle Type 2E muscular dystrophies, respectively) with varying levels of dystrophin and DGC functionality performed 50 maximal ECC contractions with simultaneous torque and electromyographic measurements (M-wave root-mean-square, M-wave RMS). ECC contractions caused all mouse lines to lose torque (p<0.001); however, deficits were greater in dystrophic mouse lines compared to WT mice (p<0.001). Loss of ECC torque did not correspond to a reduction in M-wave RMS in WT mice (p=0.080), while deficits in M-wave RMS exceeded 50% in all dystrophic mouse lines (p≤0.007). Moreover, reductions in ECC torque and M-wave RMS were greater in mdx mice compared to mL172H mice (p≤0.042). No differences were observed between mdx and Sgcb-/- mice (p≥0.337). Regression analysis revealed ≥98% of the variance in ECC torque loss could be explained by the variance in M-wave RMS in dystrophic mouse lines (p<0.001) but not within WT mice (R 2=0.211; p=0.155). By comparing mouse lines that had varying amounts and functionality of dystrophin and other DGC proteins, we observed that (1) when all DGCs are intact, plasmalemmal action potential generation and conduction is maintained, (2) deficiency of the DGC protein β-sarcoglycan is as disruptive to plasmalemmal excitability as is dystrophin deficiency and, (3) some functionally intact DGCs are better than none. Our results highlight the significant role of the DGC plays in maintaining plasmalemmal excitability and that a collective synergism (via each DGC protein) is required for this complex to function properly during ECC contractions.
Collapse
Affiliation(s)
- Cory W. Baumann
- Department of Biomedical Sciences, Ohio Musculoskeletal and Neurological Institute (OMNI), Ohio University, Athens, OH, United States
- Divisions of Rehabilitation Science and Physical Therapy, Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, MN, United States
| | - Angus Lindsay
- Divisions of Rehabilitation Science and Physical Therapy, Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, MN, United States
- School of Exercise and Nutrition Sciences, Institute for Physical Activity and Nutrition, Deakin University, Geelong, VIC, Australia
| | - Sylvia R. Sidky
- Divisions of Rehabilitation Science and Physical Therapy, Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, MN, United States
| | - James M. Ervasti
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States
| | - Gordon L. Warren
- Department of Physical Therapy, Georgia State University, Atlanta, GA, United States
| | - Dawn A. Lowe
- Divisions of Rehabilitation Science and Physical Therapy, Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, MN, United States
| |
Collapse
|
16
|
Kiriaev L, Kueh S, Morley JW, Houweling PJ, Chan S, North KN, Head SI. Dystrophin-negative slow-twitch soleus muscles are not susceptible to eccentric contraction induced injury over the lifespan of the mdx mouse. Am J Physiol Cell Physiol 2021; 321:C704-C720. [PMID: 34432537 DOI: 10.1152/ajpcell.00122.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 08/09/2021] [Indexed: 11/22/2022]
Abstract
Duchenne muscular dystrophy (DMD) is the second most common fatal genetic disease in humans and is characterized by the absence of a functional copy of the protein dystrophin from skeletal muscle. In dystrophin-negative humans and rodents, regenerated skeletal muscle fibers show abnormal branching. The number of fibers with branches and the complexity of branching increases with each cycle of degeneration/regeneration. Previously, using the mdx mouse model of DMD, we have proposed that once the number and complexity of branched fibers present in dystrophic fast-twitch EDL muscle surpasses a stable level, we term the "tipping point," the branches, in and of themselves, mechanically weaken the muscle by rupturing when subjected to high forces during eccentric contractions. Here, we use the slow-twitch soleus muscle from the dystrophic mdx mouse to study prediseased "periambulatory" dystrophy at 2-3 wk, the peak regenerative "adult" phase at 6-9 wk, and "old" at 58-112 wk. Using isolated mdx soleus muscles, we examined contractile function and response to eccentric contraction correlated with the amount and complexity of regenerated branched fibers. The intact muscle was enzymatically dispersed into individual fibers in order to count fiber branching and some muscles were optically cleared to allow laser scanning confocal microscopy. We demonstrate throughout the lifespan of the mdx mouse that dystrophic slow-twitch soleus muscle is no more susceptible to eccentric contraction-induced injury than age-matched littermate controls and that this is correlated with a reduction in the number and complexity of branched fibers compared with fast-twitch dystrophic EDL muscles.
Collapse
MESH Headings
- Age Factors
- Animals
- Disease Models, Animal
- Dystrophin/deficiency
- Dystrophin/genetics
- Kinetics
- Male
- Mice, Inbred mdx
- Muscle Contraction
- Muscle Fibers, Fast-Twitch/metabolism
- Muscle Fibers, Fast-Twitch/pathology
- Muscle Fibers, Slow-Twitch/metabolism
- Muscle Fibers, Slow-Twitch/pathology
- Muscle Strength
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/pathology
- Muscular Dystrophy, Duchenne/physiopathology
- Mutation
- Mice
Collapse
Affiliation(s)
- Leonit Kiriaev
- School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Sindy Kueh
- School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - John W Morley
- School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Peter J Houweling
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Stephen Chan
- School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Kathryn N North
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia
| | - Stewart I Head
- School of Medicine, Western Sydney University, Sydney, New South Wales, Australia
- Murdoch Children's Research Institute, Melbourne, Victoria, Australia
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| |
Collapse
|
17
|
Saclier M, Ben Larbi S, My Ly H, Moulin E, Mounier R, Chazaud B, Juban G. Interplay between myofibers and pro-inflammatory macrophages controls muscle damage in mdx mice. J Cell Sci 2021; 134:272022. [PMID: 34471933 DOI: 10.1242/jcs.258429] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 07/30/2021] [Indexed: 12/18/2022] Open
Abstract
Duchenne muscular dystrophy is a genetic muscle disease characterized by chronic inflammation and fibrosis mediated by a pro-fibrotic macrophage population expressing pro-inflammatory markers. Our aim was to characterize cellular events leading to the alteration of macrophage properties and to modulate macrophage inflammatory status using the gaseous mediator hydrogen sulfide (H2S). Using co-culture experiments, we first showed that myofibers derived from mdx mice strongly skewed the polarization of resting macrophages towards a pro-inflammatory phenotype. Treatment of mdx mice with NaHS, an H2S donor, reduced the number of pro-inflammatory macrophages in skeletal muscle, which was associated with a decreased number of nuclei per fiber, as well as reduced myofiber branching and fibrosis. Finally, we established the metabolic sensor AMP-activated protein kinase (AMPK) as a critical NaHS target in muscle macrophages. These results identify an interplay between myofibers and macrophages where dystrophic myofibers contribute to the maintenance of a highly inflammatory environment sustaining a pro-inflammatory macrophage status, which in turn favors myofiber damage, myofiber branching and establishment of fibrosis. Our results also highlight the use of H2S donors as a potential therapeutic strategy to improve the dystrophic muscle phenotype by dampening chronic inflammation. This article has an associated First Person interview with the first author of the paper.
Collapse
Affiliation(s)
- Marielle Saclier
- Department of Biosciences, University of Milan, 20133 Milan, Italy
| | - Sabrina Ben Larbi
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 5310, INSERM U1217, Université de Lyon, 69008 Lyon, France
| | - Ha My Ly
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 5310, INSERM U1217, Université de Lyon, 69008 Lyon, France
| | - Eugénie Moulin
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 5310, INSERM U1217, Université de Lyon, 69008 Lyon, France
| | - Rémi Mounier
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 5310, INSERM U1217, Université de Lyon, 69008 Lyon, France
| | - Bénédicte Chazaud
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 5310, INSERM U1217, Université de Lyon, 69008 Lyon, France
| | - Gaëtan Juban
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 5310, INSERM U1217, Université de Lyon, 69008 Lyon, France
| |
Collapse
|
18
|
Ectopic Odorant Receptor Responding to Flavor Compounds: Versatile Roles in Health and Disease. Pharmaceutics 2021; 13:pharmaceutics13081314. [PMID: 34452275 PMCID: PMC8402194 DOI: 10.3390/pharmaceutics13081314] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 08/11/2021] [Accepted: 08/17/2021] [Indexed: 12/23/2022] Open
Abstract
Prompted by the ground-breaking discovery of the rodent odorant receptor (OR) gene family within the olfactory epithelium nearly 30 years ago, followed by that of OR genes in cells of the mammalian germ line, and potentiated by the identification of ORs throughout the body, our appreciation for ORs as general chemoreceptors responding to odorant compounds in the regulation of physiological or pathophysiological processes continues to expand. Ectopic ORs are now activated by a diversity of flavor compounds and are involved in diverse physiological phenomena varying from adipogenesis to myogenesis to hepatic lipid accumulation to serotonin secretion. In this review, we outline the key biological functions of the ectopic ORs responding to flavor compounds and the underlying molecular mechanisms. We also discuss research opportunities for utilizing ectopic ORs as therapeutic strategies in the treatment of human disease as well as challenges to be overcome in the future. The recognition of the potent function, signaling pathway, and pharmacology of ectopic ORs in diverse tissues and cell types, coupled with the fact that they belong to G protein-coupled receptors, a highly druggable protein family, unequivocally highlight the potential of ectopic ORs responding to flavor compounds, especially food-derived odorant compounds, as a promising therapeutic strategy for various diseases.
Collapse
|
19
|
Ben Larbi S, Saclier M, Fessard A, Juban G, Chazaud B. Histological Analysis of Tibialis Anterior Muscle of DMDmdx4Cv Mice from 1 to 24 Months. J Neuromuscul Dis 2021; 8:513-524. [PMID: 33843691 DOI: 10.3233/jnd-200562] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND The mdx-C57/B6 mouse model does not show the clinical signs of Duchenne muscular dystrophy (DMD), although muscles exhibit hallmarks of permanent regeneration and alterations in muscle function. The DMDmdx4Cv strain exhibits very few revertant dystrophin positive myofibers, making that model suitable for studies on gene and cell therapies. OBJECTIVE The study appraises the histological evolution of the Tibialis Anterior muscle of WT and DMD mdx4Cv mutant from 1 to 24 months. METHODS Histological analysis included a series of immunostainings of muscle sections for assessing tissue features (fibrosis, lipid deposition, necrosis) and cellular characteristics (size of myofibers, number and distribution of myonuclei, number of satellite cells, vessels, macrophages). RESULTS None of the investigated cell types (satellite cells, endothelial cells, macrophages) showed variations in their density within the tissue in both WT and DMD mdx4Cv muscle. However, analyzing their number per myofiber showed that in DMD mdx4Cv, myofiber capillarization was increased from 1 to 6 months as compared with WT muscle, then dropped from 12 months. Macrophage number did not vary in WT muscle and peaked at 6 months in DMD mdx4Cv muscle. The number of satellite cells per myofiber did not vary in WT muscle while it remained high in DMD mdx4Cv muscle, starting to decrease from 12 months and being significantly lower at 24 months of age. Myofiber size was not different in DMD mdx4Cv from WT except at 24 months, when it strongly decreased in DMD mdx4Cv muscle. Necrosis and lipid deposition were rare in DMD mdx4Cv muscle. Fibrosis did not increase with age in DMD mdx4Cv muscle and was higher than in WT at 6 and 12 months of age. CONCLUSIONS As a whole, the results show a strong decrease of the myofiber size at 24 months, and an increased capillarization until 6 months of age in DMD mdx4Cv as compared with the WT. Thus, DMD mdx4Cv mice poorly recapitulates histological DMD features, and its use should take into account the age of the animals according to the purpose of the investigation.
Collapse
Affiliation(s)
- Sabrina Ben Larbi
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 2310, INSERM U1217, Université Lyon, Villeurbanne, France
| | | | - Aurélie Fessard
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 2310, INSERM U1217, Université Lyon, Villeurbanne, France
| | - Gaëtan Juban
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 2310, INSERM U1217, Université Lyon, Villeurbanne, France
| | - Bénédicte Chazaud
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 2310, INSERM U1217, Université Lyon, Villeurbanne, France
| |
Collapse
|
20
|
Mareedu S, Million ED, Duan D, Babu GJ. Abnormal Calcium Handling in Duchenne Muscular Dystrophy: Mechanisms and Potential Therapies. Front Physiol 2021; 12:647010. [PMID: 33897454 PMCID: PMC8063049 DOI: 10.3389/fphys.2021.647010] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 03/02/2021] [Indexed: 12/18/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is an X-linked muscle-wasting disease caused by the loss of dystrophin. DMD is associated with muscle degeneration, necrosis, inflammation, fatty replacement, and fibrosis, resulting in muscle weakness, respiratory and cardiac failure, and premature death. There is no curative treatment. Investigations on disease-causing mechanisms offer an opportunity to identify new therapeutic targets to treat DMD. An abnormal elevation of the intracellular calcium (Cai2+) concentration in the dystrophin-deficient muscle is a major secondary event, which contributes to disease progression in DMD. Emerging studies have suggested that targeting Ca2+-handling proteins and/or mechanisms could be a promising therapeutic strategy for DMD. Here, we provide an updated overview of the mechanistic roles the sarcolemma, sarcoplasmic/endoplasmic reticulum, and mitochondria play in the abnormal and sustained elevation of Cai2+ levels and their involvement in DMD pathogenesis. We also discuss current approaches aimed at restoring Ca2+ homeostasis as potential therapies for DMD.
Collapse
Affiliation(s)
- Satvik Mareedu
- Department of Cell Biology and Molecular Medicine, New Jersey Medical School, Rutgers University, Newark, NJ, United States
| | - Emily D Million
- Department of Molecular Microbiology and Immunology, The University of Missouri, Columbia, MO, United States
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, The University of Missouri, Columbia, MO, United States.,Department of Biomedical, Biological & Chemical Engineering, The University of Missouri, Columbia, MO, United States
| | - Gopal J Babu
- Department of Cell Biology and Molecular Medicine, New Jersey Medical School, Rutgers University, Newark, NJ, United States
| |
Collapse
|
21
|
Garcia-Pelagio KP, Pratt SJP, Lovering RM. Effects of myofiber isolation technique on sarcolemma biomechanics. Biotechniques 2020; 69:388-391. [PMID: 33000629 PMCID: PMC7686532 DOI: 10.2144/btn-2020-0087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Isolated myofibers are commonly used to understand the function of skeletal muscle in vivo. This can involve single isolated myofibers obtained from dissection or from enzymatic dissociation. Isolation via dissection allows control of sarcomere length and preserves tendon attachment but is labor-intensive, time-consuming and yields few viable myofibers. In contrast, enzymatic dissociation is fast and facile, produces hundreds of myofibers, and more importantly reduces the number of muscles/animals needed for studies. Biomechanical properties of the sarcolemma have been studied using myofibers from the extensor digitorum longus, but this has been limited to dissected myofibers, making data collection slow and difficult. We have modified this tool to perform biomechanical measurements of the sarcolemma in dissociated myofibers from the flexor digitorum brevis.
Collapse
Affiliation(s)
- Karla P Garcia-Pelagio
- Departmento de Física, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Stephen JP Pratt
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Richard M Lovering
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.,Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| |
Collapse
|
22
|
Cully TR, Rodney GG. Nox4 - RyR1 - Nox2: Regulators of micro-domain signaling in skeletal muscle. Redox Biol 2020; 36:101557. [PMID: 32506037 PMCID: PMC7283154 DOI: 10.1016/j.redox.2020.101557] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/10/2020] [Accepted: 04/23/2020] [Indexed: 12/22/2022] Open
Abstract
The ability for skeletal muscle to perform optimally can be affected by the regulation of Ca2+ within the triadic junctional space at rest. Reactive oxygen species impact muscle performance due to changes in oxidative stress, damage and redox regulation of signaling cascades. The interplay between ROS and Ca2+ signaling at the triad of skeletal muscle is therefore important to understand as it can impact the performance of healthy and diseased muscle. Here, we aimed to examine how changes in Ca2+ and redox signaling within the junctional space micro-domain of the mouse skeletal muscle fibre alters the homeostasis of these complexes. The dystrophic mdx mouse model displays increased RyR1 Ca2+ leak and increased NAD(P)H Oxidase 2 ROS. These alterations make the mdx mouse an ideal model for understanding how ROS and Ca2+ handling impact each other. We hypothesised that elevated t-tubular Nox2 ROS increases RyR1 Ca2+ leak contributing to an increase in cytoplasmic Ca2+, which could then initiate protein degradation and impaired cellular functions such as autophagy and ER stress. We found that inhibiting Nox2 ROS did not decrease RyR1 Ca2+ leak observed in dystrophin-deficient skeletal muscle. Intriguingly, another NAD(P)H isoform, Nox4, is upregulated in mice unable to produce Nox2 ROS and when inhibited reduced RyR1 Ca2+ leak. Our findings support a model in which Nox4 ROS induces RyR1 Ca2+ leak and the increased junctional space [Ca2+] exacerbates Nox2 ROS; with the cumulative effect of disruption of downstream cellular processes that would ultimately contribute to reduced muscle or cellular performance. Nox2 ROS does not influence RyR1 Ca2+ leak in skeletal muscle. Lack of Nox2 ROS increases Nox4 expression. Nox4 ROS induces RyR1 Ca2+ leak via S-nitrosylation.
Collapse
Affiliation(s)
- Tanya R Cully
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - George G Rodney
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA.
| |
Collapse
|
23
|
MyoRobot 2.0: An advanced biomechatronics platform for automated, environmentally controlled skeletal muscle single fiber biomechanics assessment employing inbuilt real-time optical imaging. Biosens Bioelectron 2019; 138:111284. [DOI: 10.1016/j.bios.2019.04.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 04/24/2019] [Indexed: 11/23/2022]
|
24
|
Friedrich O, Haug M, Reischl B, Prölß G, Kiriaev L, Head SI, Reid MB. Single muscle fibre biomechanics and biomechatronics - The challenges, the pitfalls and the future. Int J Biochem Cell Biol 2019; 114:105563. [PMID: 31255723 DOI: 10.1016/j.biocel.2019.105563] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 06/25/2019] [Accepted: 06/27/2019] [Indexed: 11/19/2022]
Abstract
Interest in muscle biomechanics is growing with availabilities of patient biopsies and animal models related to muscle diseases, muscle wasting (sarcopenia, cachexia), exercise and drug effects. However, development of technologies or facilitated systems required to measure biomechanical and contractile properties of single fibres has not kept pace with this demand. Most studies use manual mechatronics systems that have not changed in decades and are confined to a few labs worldwide. Available commercial systems are expensive and limited in versatility, throughput and user-friendliness. We review major standard systems available from research labs and commercial sources, and benchmark those to our recently developed automated MyoRobot biomechatronics platform that provides versatility to cover multiple organ scales, is flexible in programming for active/passive muscle biomechanics using custom-made graphics user interfaces, employs on-the-fly data analyses and does not rely on external research microscopes. With higher throughput, this system blends Industry 4.0 automation principles into myology.
Collapse
Affiliation(s)
- Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany; School of Medical Sciences, University of New South Wales (USNW), Wallace Wurth Building, 2052 NSW, Sydney Australia; Muscle Research Centre Erlangen (MURCE), Henkestr. 91, 91052 Erlangen, Germany.
| | - Michael Haug
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - B Reischl
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - G Prölß
- Institute of Medical Biotechnology, Friedrich-Alexander University Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Leon Kiriaev
- School of Medical Sciences, University of New South Wales (USNW), Wallace Wurth Building, 2052 NSW, Sydney Australia
| | - Stewart I Head
- School of Medical Sciences, University of New South Wales (USNW), Wallace Wurth Building, 2052 NSW, Sydney Australia; Department of Physiology, School of Medicine, University of Western Sydney, Campbelltown Campus, Western Sydney, 2751 NSW, Australia
| | - Michael B Reid
- College of Health and Human Performance, University of Florida, Gainesville, FL, USA
| |
Collapse
|
25
|
Kiriaev L, Kueh S, Morley JW, North KN, Houweling PJ, Head SI. Branched fibers from old fast-twitch dystrophic muscles are the sites of terminal damage in muscular dystrophy. Am J Physiol Cell Physiol 2018; 314:C662-C674. [PMID: 29412689 DOI: 10.1152/ajpcell.00161.2017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A striking pathological feature of dystrophinopathies is the presence of morphologically abnormal branched skeletal muscle fibers. The deterioration of muscle contractile function in Duchenne muscular dystrophy is accompanied by both an increase in number and complexity of these branched fibers. We propose that when number and complexity of branched fibers reaches a critical threshold, or "tipping point," the branches in and of themselves are the site of contraction-induced rupture. In the present study, we use the dystrophic mdx mouse and littermate controls to study the prediseased dystrophic fast-twitch extensor digitorum longus (EDL) muscle at 2-3 wk, the peak myonecrotic phase at 6-9 wk, and finally, "old," at 58-112 wk. Using a combination of isolated muscle function contractile measurements coupled with single-fiber imaging and confocal microscope imaging of cleared whole muscles, we identified a distinct pathophysiology, acute fiber rupture at branch nodes, which occurs in "old" fast-twitch EDL muscle approaching the end stage of the dystrophinopathy muscle disease, where the EDL muscles are entirely composed of complexed branched fibers. This evidence supports our concept of "tipping point" where the number and extent of fiber branching reach a level where the branching itself terminally compromises muscle function, irrespective of the absence of dystrophin.
Collapse
Affiliation(s)
- Leonit Kiriaev
- School of Medical Sciences, University of New South Wales , Sidney, New South Wales , Australia
| | - Sindy Kueh
- School of Medical Sciences, University of New South Wales , Sidney, New South Wales , Australia.,School of Medicine, Western Sydney University, Penrith, New South Wales , Australia
| | - John W Morley
- School of Medicine, Western Sydney University, Penrith, New South Wales , Australia
| | - Kathryn N North
- Murdoch Children's Research Institute , Melbourne, Victoria , Australia
| | - Peter J Houweling
- Murdoch Children's Research Institute , Melbourne, Victoria , Australia
| | - Stewart I Head
- School of Medical Sciences, University of New South Wales , Sidney, New South Wales , Australia.,School of Medicine, Western Sydney University, Penrith, New South Wales , Australia
| |
Collapse
|
26
|
Schneidereit D, Nübler S, Prölß G, Reischl B, Schürmann S, Müller OJ, Friedrich O. Optical prediction of single muscle fiber force production using a combined biomechatronics and second harmonic generation imaging approach. LIGHT, SCIENCE & APPLICATIONS 2018; 7:79. [PMID: 30374401 PMCID: PMC6199289 DOI: 10.1038/s41377-018-0080-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 09/19/2018] [Accepted: 09/24/2018] [Indexed: 05/22/2023]
Abstract
Skeletal muscle is an archetypal organ whose structure is tuned to match function. The magnitude of order in muscle fibers and myofibrils containing motor protein polymers determines the directed force output of the summed force vectors and, therefore, the muscle's power performance on the structural level. Structure and function can change dramatically during disease states involving chronic remodeling. Cellular remodeling of the cytoarchitecture has been pursued using noninvasive and label-free multiphoton second harmonic generation (SHG) microscopy. Hereby, structure parameters can be extracted as a measure of myofibrillar order and thus are suggestive of the force output that a remodeled structure can still achieve. However, to date, the parameters have only been an indirect measure, and a precise calibration of optical SHG assessment for an exerted force has been elusive as no technology in existence correlates these factors. We engineered a novel, automated, high-precision biomechatronics system into a multiphoton microscope allows simultaneous isometric Ca2+-graded force or passive viscoelasticity measurements and SHG recordings. Using this MechaMorph system, we studied force and SHG in single EDL muscle fibers from wt and mdx mice; the latter serves as a model for compromised force and abnormal myofibrillar structure. We present Ca2+-graded isometric force, pCa-force curves, passive viscoelastic parameters and 3D structure in the same fiber for the first time. Furthermore, we provide a direct calibration of isometric force to morphology, which allows noninvasive prediction of the force output of single fibers from only multiphoton images, suggesting a potential application in the diagnosis of myopathies.
Collapse
Affiliation(s)
- Dominik Schneidereit
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU Erlangen-Nürnberg, Paul-Gordan-Str. 7, 91052 Erlangen, Germany
| | - Stefanie Nübler
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU Erlangen-Nürnberg, Paul-Gordan-Str. 7, 91052 Erlangen, Germany
| | - Gerhard Prölß
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Barbara Reischl
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
| | - Sebastian Schürmann
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU Erlangen-Nürnberg, Paul-Gordan-Str. 7, 91052 Erlangen, Germany
- Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | - Oliver J Müller
- Department of Internal Medicine III, University of Kiel, Arnold-Heller-Str. 3, 24105 Kiel, Germany
- DZHK (German Center for Cardiovascular Research) Partner Site Hamburg/Kiel/Lübeck, Kiel, Germany
| | - Oliver Friedrich
- Institute of Medical Biotechnology, Friedrich-Alexander-University (FAU) Erlangen-Nürnberg, Paul-Gordan-Str. 3, 91052 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), FAU Erlangen-Nürnberg, Paul-Gordan-Str. 7, 91052 Erlangen, Germany
- Muscle Research Center Erlangen (MURCE), Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| |
Collapse
|
27
|
The MyoRobot: A novel automated biomechatronics system to assess voltage/Ca 2+ biosensors and active/passive biomechanics in muscle and biomaterials. Biosens Bioelectron 2017; 102:589-599. [PMID: 29245144 DOI: 10.1016/j.bios.2017.12.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 11/11/2017] [Accepted: 12/05/2017] [Indexed: 11/21/2022]
Abstract
We engineered an automated biomechatronics system, MyoRobot, for robust objective and versatile assessment of muscle or polymer materials (bio-)mechanics. It covers multiple levels of muscle biosensor assessment, e.g. membrane voltage or contractile apparatus Ca2+ ion responses (force resolution 1µN, 0-10mN for the given sensor; [Ca2+] range ~ 100nM-25µM). It replaces previously tedious manual protocols to obtain exhaustive information on active/passive biomechanical properties across various morphological tissue levels. Deciphering mechanisms of muscle weakness requires sophisticated force protocols, dissecting contributions from altered Ca2+ homeostasis, electro-chemical, chemico-mechanical biosensors or visco-elastic components. From whole organ to single fibre levels, experimental demands and hardware requirements increase, limiting biomechanics research potential, as reflected by only few commercial biomechatronics systems that can address resolution, experimental versatility and mostly, automation of force recordings. Our MyoRobot combines optical force transducer technology with high precision 3D actuation (e.g. voice coil, 1µm encoder resolution; stepper motors, 4µm feed motion), and customized control software, enabling modular experimentation packages and automated data pre-analysis. In small bundles and single muscle fibres, we demonstrate automated recordings of (i) caffeine-induced-, (ii) electrical field stimulation (EFS)-induced force, (iii) pCa-force, (iv) slack-tests and (v) passive length-tension curves. The system easily reproduces results from manual systems (two times larger stiffness in slow over fast muscle) and provides novel insights into unloaded shortening velocities (declining with increasing slack lengths). The MyoRobot enables automated complex biomechanics assessment in muscle research. Applications also extend to material sciences, exemplarily shown here for spider silk and collagen biopolymers.
Collapse
|
28
|
Lacour F, Vezin E, Bentzinger CF, Sincennes MC, Giordani L, Ferry A, Mitchell R, Patel K, Rudnicki MA, Chaboissier MC, Chassot AA, Le Grand F. R-spondin1 Controls Muscle Cell Fusion through Dual Regulation of Antagonistic Wnt Signaling Pathways. Cell Rep 2017; 18:2320-2330. [PMID: 28273449 PMCID: PMC5357729 DOI: 10.1016/j.celrep.2017.02.036] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 12/15/2016] [Accepted: 02/10/2017] [Indexed: 12/21/2022] Open
Abstract
Wnt-mediated signals are involved in many important steps in mammalian regeneration. In multiple cell types, the R-spondin (Rspo) family of secreted proteins potently activates the canonical Wnt/β-catenin pathway. Here, we identify Rspo1 as a mediator of skeletal muscle tissue repair. First, we show that deletion of Rspo1 results in global alteration of muscle regeneration kinetics following acute injury. We find that muscle progenitor cells lacking Rspo1 show delayed differentiation due to reduced activation of Wnt/β-catenin target genes. Furthermore, muscle cells lacking Rspo1 have a fusion phenotype leading to larger myotubes containing supernumerary nuclei both in vitro and in vivo. The increase in muscle fusion was dependent on downregulation of Wnt/β-catenin and upregulation of non-canonical Wnt7a/Fzd7/Rac1 signaling. We conclude that reciprocal control of antagonistic Wnt signaling pathways by Rspo1 in muscle stem cell progeny is a key step ensuring normal tissue architecture restoration following acute damage.
Collapse
Affiliation(s)
- Floriane Lacour
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, 75013 Paris, France
| | - Elsa Vezin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, 75013 Paris, France
| | - C Florian Bentzinger
- Département de pharmacologie et physiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, J1H5N4 QC, Canada
| | - Marie-Claude Sincennes
- Sprott Center for Stem Cell Research, Ottawa Hospital Research Institute, Regenerative Medicine Program, Ottawa, K1H8L6 ON, Canada; Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, K1H 8M5 ON, Canada
| | - Lorenzo Giordani
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, 75013 Paris, France
| | - Arnaud Ferry
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, 75013 Paris, France
| | - Robert Mitchell
- School of Biological Sciences, University of Reading, RG6 6UB Reading, UK
| | - Ketan Patel
- School of Biological Sciences, University of Reading, RG6 6UB Reading, UK; Freiburg Institute for Advanced Studies, Albert-Ludwigs-Universität Freiburg, 79104 Freiburg im Breisgau, Germany
| | - Michael A Rudnicki
- Sprott Center for Stem Cell Research, Ottawa Hospital Research Institute, Regenerative Medicine Program, Ottawa, K1H8L6 ON, Canada; Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, K1H 8M5 ON, Canada
| | | | | | - Fabien Le Grand
- Sorbonne Universités, UPMC Univ Paris 06, INSERM UMRS974, CNRS FRE3617, Center for Research in Myology, 75013 Paris, France.
| |
Collapse
|
29
|
Mackey AL, Kjaer M. The breaking and making of healthy adult human skeletal muscle in vivo. Skelet Muscle 2017; 7:24. [PMID: 29115986 PMCID: PMC5688812 DOI: 10.1186/s13395-017-0142-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/23/2017] [Indexed: 01/11/2023] Open
Abstract
Background While muscle regeneration has been extensively studied in animal and cell culture models, in vivo myogenesis in adult human skeletal muscle has not been investigated in detail. Methods Using forced lengthening contractions induced by electrical stimulation, we induced myofibre injury in young healthy males. Muscle biopsies were collected from the injured leg 7 and 30 days after muscle injury and from the uninjured leg as a control. Immuno-stained single muscle fibres and muscle cross sections were studied by wide-field and confocal microscopy. Samples were also studied at the ultra-structural level by electron microscopy. Results Microscopy of single muscle fibres in 3 dimensions revealed a repeating pattern of necrotic and regenerating zones along the length of the same myofibre, characterised by extensive macrophage infiltration alongside differentiating myogenic progenitor cells and myotubes: the hallmarks of myogenesis. The myofibre basement membrane was preserved during these processes and interestingly was seen at a later stage as a second basement membrane surrounding the regenerating fibres. Conclusions This is the first work to document in vivo myogenesis in humans in detail and highlights the importance of the basement membrane in the process of regeneration. In addition, it provides insight into parallels between the regeneration of adult skeletal muscle in mouse and man, confirming that this model may be a useful tool in investigating myofibre and matrix formation, as well as specific cell types, during regeneration from the perspective of human muscle.
Collapse
Affiliation(s)
- Abigail L Mackey
- Institute of Sports Medicine Copenhagen, Department of Orthopaedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark. .,Center for Healthy Aging, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Michael Kjaer
- Institute of Sports Medicine Copenhagen, Department of Orthopaedic Surgery M, Bispebjerg Hospital, Copenhagen, Denmark.,Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
30
|
Barker RG, Horvath D, van der Poel C, Murphy RM. Benefits of Prenatal Taurine Supplementation in Preventing the Onset of Acute Damage in the Mdx Mouse. PLOS CURRENTS 2017; 9:ecurrents.md.9a3e357a0154d01050b591601cbd4fdb. [PMID: 29188135 PMCID: PMC5693597 DOI: 10.1371/currents.md.9a3e357a0154d01050b591601cbd4fdb] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
INTRODUCTION Duchenne Muscular Dystrophy (DMD) is a debilitating muscle wasting disorder with no cure. Safer supplements and therapies are needed to improve the severity of symptoms, as severe side effects are associated with the only effective treatment, corticosteroids. The amino acid taurine has shown promise in ameliorating dystrophic symptoms in mdx mice, an animal model of DMD, however little work is in 21-28 (d)ay animals, the period of natural peak damage. METHODS This study compares the effect of prenatal taurine supplementation on tibialis anterior (TA) in situ contractile function, histopathological characteristics and the abundance of Ca2+-handling as well as pathologically relevant proteins in non-exercised mdx mice at 28 and 70 d. RESULTS Supplementation elevated TA taurine content by 25% (p<0.05), ameliorated in situ specific force by 60% (p<0.05) and improved histological characteristics in 28 d mdx mice; however no benefit was seen in 70 d mice, where background pathology was initially stable. Age specific effects in SERCA1, calsequestrin 1 (CSQ1), CSQ2, utrophin and myogenin protein abundances were seen between both 28 and 70 d mdx and mdx taurine-supplemented mice. DISCUSSION Considering these findings and that taurine is a relatively cost effective, readily accessible and side effect free dietary supplement, we propose further investigation into taurine supplementation during pregnancy in a protective capacity, reminiscent of folate in the prevention of spinal bifida.
Collapse
Affiliation(s)
- Robert G Barker
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, Melbourne, Victoria, Australia
| | - Deanna Horvath
- Department of Physiology, Anatomy, and Microbiology, La Trobe University, Melbourne, Victoria, Australia
| | - Chris van der Poel
- Department of Physiology, Anatomy, and Microbiology, La Trobe University, Melbourne, Victoria, Australia
| | - Robyn M Murphy
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, Melbourne, Victoria, Australia
| |
Collapse
|
31
|
Nielsen C, Potter RM, Borowy C, Jacinto K, Kumar R, Carlson CG. Postnatal Hyperplasic Effects of ActRIIB Blockade in a Severely Dystrophic Muscle. J Cell Physiol 2017; 232:1774-1793. [PMID: 27859236 DOI: 10.1002/jcp.25694] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 11/16/2016] [Indexed: 01/26/2023]
Abstract
The efficacy of two ActRIIB ligand-trapping agents (RAP-031 and RAP-435) in treating muscular dystrophy was examined by determining their morphological effects on the severely dystrophic triangularis sterni (TS) muscle of the mdx mouse, a model for Duchenne muscular dystrophy. These agents trap all endogenous ligands to the ActRIIB receptor and thereby block myostatin signaling in a highly selective manner. Short-term (1 month) and long-term (3 months) in vivo treatment of 1-month-old mdx mice increased myonuclei and fiber cross section (FCS) density but did not alter individual fiber size. Vehicle-treated mdx mice exhibited age-dependent increases in myonuclei and FCS density, and age-dependent reductions in centronucleation that were each enhanced by treatment with RAP-435. Distributions of FCS area (FCSA) in the mdx TS were 90% identical to those from untreated age-matched nondystrophic mice and were unaltered by the substantial fiber hyperplasia observed with age and RAP-435 treatment. These results were inconsistent with injury-induced fiber regeneration which produces altered FCSA distributions characterized by a distinct class of smaller regenerated fibers. Nondystrophic mice exhibited a constant postnatal density of fiber cross sections and myonuclei, and RAP-435 treatment of nondystrophic mice increased TS mean FCSA but had no effects on myonuclei or FCS density. These results demonstrating a continual postnatal proliferation and fusion of satellite cells and a response to myostatin blockade characteristic of developing prenatal muscle suggest that the lack of dystrophin directly results in unrestrained postnatal satellite cell activation that is not necessarily dependent upon prior fiber degeneration. J. Cell. Physiol. 232: 1774-1793, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Cory Nielsen
- Department of Physiology, Midwestern University Glendale, Glendale, Arizona
| | - Ross M Potter
- Department of Physiology, Midwestern University Glendale, Glendale, Arizona
| | - Christopher Borowy
- Department of Physiology, Midwestern University Glendale, Glendale, Arizona
| | - Kimberly Jacinto
- Department of Physiology, Midwestern University Glendale, Glendale, Arizona
| | - Ravi Kumar
- Acceleron Pharma, Inc., Cambridge, Massachusetts
| | - C George Carlson
- Department of Physiology, Midwestern University Glendale, Glendale, Arizona
| |
Collapse
|
32
|
Hogarth MW, Houweling PJ, Thomas KC, Gordish-Dressman H, Bello L, Pegoraro E, Hoffman EP, Head SI, North KN. Evidence for ACTN3 as a genetic modifier of Duchenne muscular dystrophy. Nat Commun 2017; 8:14143. [PMID: 28139640 PMCID: PMC5290331 DOI: 10.1038/ncomms14143] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 11/22/2016] [Indexed: 01/01/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is characterized by muscle degeneration and progressive weakness. There is considerable inter-patient variability in disease onset and progression, which can confound the results of clinical trials. Here we show that a common null polymorphism (R577X) in ACTN3 results in significantly reduced muscle strength and a longer 10 m walk test time in young, ambulant patients with DMD; both of which are primary outcome measures in clinical trials. We have developed a double knockout mouse model, which also shows reduced muscle strength, but is protected from stretch-induced eccentric damage with age. This suggests that α-actinin-3 deficiency reduces muscle performance at baseline, but ameliorates the progression of dystrophic pathology. Mechanistically, we show that α-actinin-3 deficiency triggers an increase in oxidative muscle metabolism through activation of calcineurin, which likely confers the protective effect. Our studies suggest that ACTN3 R577X genotype is a modifier of clinical phenotype in DMD patients.
Collapse
Affiliation(s)
- Marshall W Hogarth
- Institute for Neuroscience and Muscle Research, The Children's Hospital Westmead, New South Wales 2145, Australia.,Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, New South Wales 2006, Australia
| | - Peter J Houweling
- Institute for Neuroscience and Muscle Research, The Children's Hospital Westmead, New South Wales 2145, Australia.,School of Medical Sciences, University of New South Wales, New South Wales 2052, Australia.,Murdoch Childrens Research Institute, Melbourne, Victoria 3052, Australia.,Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Victoria 3010, Australia
| | - Kristen C Thomas
- Institute for Neuroscience and Muscle Research, The Children's Hospital Westmead, New South Wales 2145, Australia
| | - Heather Gordish-Dressman
- Research Centre for Genetic Medicine, Children's National Medical Centre, Washington DC 20010, USA
| | - Luca Bello
- Research Centre for Genetic Medicine, Children's National Medical Centre, Washington DC 20010, USA.,Department of Neurosciences, University of Padova, Padova 35122, Italy
| | | | - Elena Pegoraro
- Department of Neurosciences, University of Padova, Padova 35122, Italy
| | - Eric P Hoffman
- Research Centre for Genetic Medicine, Children's National Medical Centre, Washington DC 20010, USA
| | - Stewart I Head
- School of Medical Sciences, University of New South Wales, New South Wales 2052, Australia
| | - Kathryn N North
- Institute for Neuroscience and Muscle Research, The Children's Hospital Westmead, New South Wales 2145, Australia.,Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, New South Wales 2006, Australia.,Murdoch Childrens Research Institute, Melbourne, Victoria 3052, Australia.,Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Victoria 3010, Australia
| |
Collapse
|
33
|
Allen DG, Whitehead NP, Froehner SC. Absence of Dystrophin Disrupts Skeletal Muscle Signaling: Roles of Ca2+, Reactive Oxygen Species, and Nitric Oxide in the Development of Muscular Dystrophy. Physiol Rev 2016; 96:253-305. [PMID: 26676145 DOI: 10.1152/physrev.00007.2015] [Citation(s) in RCA: 272] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Dystrophin is a long rod-shaped protein that connects the subsarcolemmal cytoskeleton to a complex of proteins in the surface membrane (dystrophin protein complex, DPC), with further connections via laminin to other extracellular matrix proteins. Initially considered a structural complex that protected the sarcolemma from mechanical damage, the DPC is now known to serve as a scaffold for numerous signaling proteins. Absence or reduced expression of dystrophin or many of the DPC components cause the muscular dystrophies, a group of inherited diseases in which repeated bouts of muscle damage lead to atrophy and fibrosis, and eventually muscle degeneration. The normal function of dystrophin is poorly defined. In its absence a complex series of changes occur with multiple muscle proteins showing reduced or increased expression or being modified in various ways. In this review, we will consider the various proteins whose expression and function is changed in muscular dystrophies, focusing on Ca(2+)-permeable channels, nitric oxide synthase, NADPH oxidase, and caveolins. Excessive Ca(2+) entry, increased membrane permeability, disordered caveolar function, and increased levels of reactive oxygen species are early changes in the disease, and the hypotheses for these phenomena will be critically considered. The aim of the review is to define the early damage pathways in muscular dystrophy which might be appropriate targets for therapy designed to minimize the muscle degeneration and slow the progression of the disease.
Collapse
Affiliation(s)
- David G Allen
- Sydney Medical School & Bosch Institute, University of Sydney, New South Wales, Australia; and Department of Physiology & Biophysics, University of Washington, Seattle, Washington
| | - Nicholas P Whitehead
- Sydney Medical School & Bosch Institute, University of Sydney, New South Wales, Australia; and Department of Physiology & Biophysics, University of Washington, Seattle, Washington
| | - Stanley C Froehner
- Sydney Medical School & Bosch Institute, University of Sydney, New South Wales, Australia; and Department of Physiology & Biophysics, University of Washington, Seattle, Washington
| |
Collapse
|
34
|
Pichavant C, Burkholder TJ, Pavlath GK. Decrease of myofiber branching via muscle-specific expression of the olfactory receptor mOR23 in dystrophic muscle leads to protection against mechanical stress. Skelet Muscle 2016; 6:2. [PMID: 26798450 PMCID: PMC4721043 DOI: 10.1186/s13395-016-0077-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 01/05/2016] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Abnormal branched myofibers within skeletal muscles are commonly found in diverse animal models of muscular dystrophy as well as in patients. Branched myofibers from dystrophic mice are more susceptible to break than unbranched myofibers suggesting that muscles containing a high percentage of these myofibers are more prone to injury. Previous studies showed ubiquitous over-expression of mouse olfactory receptor 23 (mOR23), a G protein-coupled receptor, in wild type mice decreased myofiber branching. Whether mOR23 over-expression specifically in skeletal muscle cells is sufficient to mitigate myofiber branching in dystrophic muscle is unknown. METHODS We created a novel transgenic mouse over-expressing mOR23 specifically in muscle cells and then bred with dystrophic (mdx) mice. Myofiber branching was analyzed in these two transgenic mice and membrane integrity was assessed by Evans blue dye fluorescence. RESULTS mOR23 over-expression in muscle led to a decrease of myofiber branching after muscle regeneration in non-dystrophic mouse muscles and reduced the severity of myofiber branching in mdx mouse muscles. Muscles from mdx mouse over-expressing mOR23 significantly exhibited less damage to eccentric contractions than control mdx muscles. CONCLUSIONS The decrease of myofiber branching in mdx mouse muscles over-expressing mOR23 reduced the amount of membrane damage induced by mechanical stress. These results suggest that modifying myofiber branching in dystrophic patients, while not preventing degeneration, could be beneficial for mitigating some of the effects of the disease process.
Collapse
Affiliation(s)
- Christophe Pichavant
- Department of Pharmacology, Emory University, Atlanta, GA USA ; Present address: Department of Genetics, Stanford University, Stanford, CA USA
| | - Thomas J Burkholder
- School of Applied Physiology, Georgia Institute of Technology, Atlanta, GA USA
| | - Grace K Pavlath
- Department of Pharmacology, Emory University, Atlanta, GA USA ; 1510 Clifton Road, Room 5024, Atlanta, GA 30322 USA
| |
Collapse
|
35
|
Carlson CG, Potter R, Yu V, Luo K, Lavin J, Nielsen C. In vivo
treatment with the NF-κB inhibitor ursodeoxycholic acid (UDCA) improves tension development in the isolated mdx
costal diaphragm. Muscle Nerve 2015; 53:431-7. [DOI: 10.1002/mus.24755] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 06/19/2015] [Accepted: 06/26/2015] [Indexed: 11/09/2022]
Affiliation(s)
- C. George Carlson
- Department of Physiology; Midwestern University Glendale; Glendale Arizona 85308
| | - Ross Potter
- Department of Physiology; Midwestern University Glendale; Glendale Arizona 85308
| | - Vivien Yu
- Department of Physiology; Midwestern University Glendale; Glendale Arizona 85308
| | - Kevin Luo
- Department of Physiology; Midwestern University Glendale; Glendale Arizona 85308
| | - Jesse Lavin
- Department of Physiology; Midwestern University Glendale; Glendale Arizona 85308
| | - Cory Nielsen
- Department of Physiology; Midwestern University Glendale; Glendale Arizona 85308
| |
Collapse
|
36
|
Mechanical Overloading Increases Maximal Force and Reduces Fragility in Hind Limb Skeletal Muscle from Mdx Mouse. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:2012-24. [DOI: 10.1016/j.ajpath.2015.03.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 01/30/2015] [Accepted: 03/09/2015] [Indexed: 12/20/2022]
|
37
|
Duddy W, Duguez S, Johnston H, Cohen TV, Phadke A, Gordish-Dressman H, Nagaraju K, Gnocchi V, Low S, Partridge T. Muscular dystrophy in the mdx mouse is a severe myopathy compounded by hypotrophy, hypertrophy and hyperplasia. Skelet Muscle 2015; 5:16. [PMID: 25987977 PMCID: PMC4434871 DOI: 10.1186/s13395-015-0041-y] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Accepted: 04/16/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Preclinical testing of potential therapies for Duchenne muscular dystrophy (DMD) is conducted predominantly of the mdx mouse. But lack of a detailed quantitative description of the pathology of this animal limits our ability to evaluate the effectiveness of putative therapies or their relevance to DMD. METHODS Accordingly, we have measured the main cellular components of muscle growth and regeneration over the period of postnatal growth and early pathology in mdx and wild-type (WT) mice; phalloidin binding is used as a measure of fibre size, myonuclear counts and BrdU labelling as records of myogenic activity. RESULTS We confirm a two-phase postnatal growth pattern in WT muscle: first, increase in myonuclear number over weeks 1 to 3, then expansion of myonuclear domain. Mdx muscle growth lags behind that of WT prior to overt signs of pathology. Fibres are smaller, with fewer myonuclei and smaller myonuclear domains. Moreover, satellite cells are more readily detached from mdx than WT muscle fibres. At 3 weeks, mdx muscles enter a phase of florid myonecrosis, accompanied by concurrent regeneration of an intensity that results in complete replacement of pre-existing muscle over the succeeding 3 to 4 weeks. Both WT and mdx muscles attain maximum size by 12 to 14 weeks, mdx muscle fibres being up to 50% larger than those of WT as they become increasingly branched. Mdx muscle fibres also become hypernucleated, containing twice as many myonuclei per sarcoplasmic volume, as those of WT, the excess corresponding to the number of centrally placed myonuclei. CONCLUSIONS The best-known consequence of lack of dystrophin that is common to DMD and the mdx mouse is the conspicuous necrosis and regeneration of muscle fibres. We present protocols for measuring this in terms both of loss of muscle nuclei previously labelled with BrdU and of the intensity of myonuclear labelling with BrdU administered during the regeneration period. Both measurements can be used to assess the efficacy of putative antinecrotic agents. We also show that lack of dystrophin is associated with a number of previously unsuspected abnormalities of muscle fibre structure and function that do not appear to be directly associated with myonecrosis.
Collapse
Affiliation(s)
- William Duddy
- Center for Genetic Medicine Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington DC, 20010 USA ; Myology Center of Research, Institut de Myologie Pitié-Salpétrière - Bâtiment Babinski, 75651 Paris Cedex 13, France
| | - Stephanie Duguez
- Center for Genetic Medicine Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington DC, 20010 USA ; Myology Center of Research, Institut de Myologie Pitié-Salpétrière - Bâtiment Babinski, 75651 Paris Cedex 13, France
| | - Helen Johnston
- Center for Genetic Medicine Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington DC, 20010 USA
| | - Tatiana V Cohen
- Center for Genetic Medicine Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington DC, 20010 USA ; Center for Genetic Muscle Disorders, Kennedy Krieger Institute, 801 N. Broadway, Baltimore, MD 21205 USA
| | - Aditi Phadke
- Center for Genetic Medicine Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington DC, 20010 USA
| | - Heather Gordish-Dressman
- Center for Genetic Medicine Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington DC, 20010 USA
| | - Kanneboyina Nagaraju
- Center for Genetic Medicine Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington DC, 20010 USA
| | - Viola Gnocchi
- Center for Genetic Medicine Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington DC, 20010 USA
| | - SiewHui Low
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218 USA
| | - Terence Partridge
- Center for Genetic Medicine Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington DC, 20010 USA
| |
Collapse
|
38
|
Hernández-Ochoa EO, Pratt SJP, Garcia-Pelagio KP, Schneider MF, Lovering RM. Disruption of action potential and calcium signaling properties in malformed myofibers from dystrophin-deficient mice. Physiol Rep 2015; 3:3/4/e12366. [PMID: 25907787 PMCID: PMC4425971 DOI: 10.14814/phy2.12366] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Duchenne muscular dystrophy (DMD), the most common and severe muscular dystrophy, is caused by the absence of dystrophin. Muscle weakness and fragility (i.e., increased susceptibility to damage) are presumably due to structural instability of the myofiber cytoskeleton, but recent studies suggest that the increased presence of malformed/branched myofibers in dystrophic muscle may also play a role. We have previously studied myofiber morphology in healthy wild-type (WT) and dystrophic (MDX) skeletal muscle. Here, we examined myofiber excitability using high-speed confocal microscopy and the voltage-sensitive indicator di-8-butyl-amino-naphthyl-ethylene-pyridinium-propyl-sulfonate (di-8-ANEPPS) to assess the action potential (AP) properties. We also examined AP-induced Ca2+ transients using high-speed confocal microscopy with rhod-2, and assessed sarcolemma fragility using elastimetry. AP recordings showed an increased width and time to peak in malformed MDX myofibers compared to normal myofibers from both WT and MDX, but no significant change in AP amplitude. Malformed MDX myofibers also exhibited reduced AP-induced Ca2+ transients, with a further Ca2+ transient reduction in the branches of malformed MDX myofibers. Mechanical studies indicated an increased sarcolemma deformability and instability in malformed MDX myofibers. The data suggest that malformed myofibers are functionally different from myofibers with normal morphology. The differences seen in AP properties and Ca2+ signals suggest changes in excitability and remodeling of the global Ca2+ signal, both of which could underlie reported weakness in dystrophic muscle. The biomechanical changes in the sarcolemma support the notion that malformed myofibers are more susceptible to damage. The high prevalence of malformed myofibers in dystrophic muscle may contribute to the progressive strength loss and fragility seen in dystrophic muscles.
Collapse
Affiliation(s)
- Erick O Hernández-Ochoa
- Department of Biochemistry & Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Stephen J P Pratt
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Karla P Garcia-Pelagio
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Martin F Schneider
- Department of Biochemistry & Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland
| | - Richard M Lovering
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland
| |
Collapse
|
39
|
Abstract
Muscle cells have an elaborate plasma membrane and t-tubule system that has been evolutionarily refined to maximize electrical conductivity for synchronous muscle contraction. However, this elaborate plasma membrane network has intrinsic vulnerabilities to stretch-induced membrane injury, and thus requires ongoing maintenance and repair. Herein we discuss the types of membrane injuries encountered by myofibers in healthy muscle and in muscular dystrophy. We review the different mechanisms by which muscle fibers in patients with muscular dystrophy are rendered more susceptible to injury, and we summarize the latest developments in our understanding of how the muscular dystrophy protein dysferlin mediates satellite-cell independent membrane repair.
Collapse
Affiliation(s)
- Sandra T Cooper
- Institute for Neuroscience and Muscle Research, Kids Research Institute, The Children's Hospital at Westmead, Sydney, New South Wales, Australia Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, New South Wales, Australia
| | - Stewart I Head
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales, Australia
| |
Collapse
|
40
|
Steinberger M, Föller M, Vogelgesang S, Krautwald M, Landsberger M, Winkler CK, Kasch J, Füchtbauer EM, Kuhl D, Voelkl J, Lang F, Brinkmeier H. Lack of the serum- and glucocorticoid-inducible kinase SGK1 improves muscle force characteristics and attenuates fibrosis in dystrophic mdx mouse muscle. Pflugers Arch 2014; 467:1965-74. [DOI: 10.1007/s00424-014-1645-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 10/10/2014] [Accepted: 10/31/2014] [Indexed: 02/06/2023]
|
41
|
Unveiling transcription factor regulation and differential co-expression genes in Duchenne muscular dystrophy. Diagn Pathol 2014; 9:210. [PMID: 25338682 PMCID: PMC4312468 DOI: 10.1186/s13000-014-0210-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 10/12/2014] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Gene expression analysis is powerful for investigating the underlying mechanisms of Duchenne muscular dystrophy (DMD). Previous studies mainly neglected co-expression or transcription factor (TF) information. Here we integrated TF information into differential co-expression analysis (DCEA) to explore new understandings of DMD pathogenesis. METHODS Using two microarray datasets from Gene Expression Omnibus (GEO) database, we firstly detected differentially expressed genes (DEGs) and pathways enriched with DEGs. Secondly, we constructed differentially regulated networks to integrate the TF-to-target information and the differential co-expression genes. RESULTS A total of 454 DEGs were detected and both KEGG pathway and ingenuity pathway analysis revealed that pathways enriched with aberrantly regulated genes are mostly involved in the immune response processes. DCEA results generated 610 pairs of DEGs regulated by at least one common TF, including 78 pairs of co-expressed DEGs. A network was constructed to illustrate their relationships and a subnetwork for DMD related molecules was constructed to show genes and TFs that may play important roles in the secondary changes of DMD. Among the DEGs which shared TFs with DMD, six genes were co-expressed with DMD, including ATP1A2, C1QB, MYOF, SAT1, TRIP10, and IFI6. CONCLUSION Our results may provide a new understanding of DMD and contribute potential targets for future therapeutic tests. VIRTUAL SLIDES The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_210.
Collapse
|
42
|
Mázala DAG, Grange RW, Chin ER. The role of proteases in excitation-contraction coupling failure in muscular dystrophy. Am J Physiol Cell Physiol 2014; 308:C33-40. [PMID: 25298424 DOI: 10.1152/ajpcell.00267.2013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Duchenne muscular dystrophy (DMD) is one of the most frequent types of muscular dystrophy. Alterations in intracellular calcium (Ca(2+)) handling are thought to contribute to the disease severity in DMD, possibly due to the activation of Ca(2+)-activated proteases. The purpose of this study was twofold: 1) to determine whether prolonged excitation-contraction (E-C) coupling disruption following repeated contractions is greater in animals lacking both dystrophin and utrophin (mdx/Utr(-/-)) compared with mice lacking only dystrophin (mdx); and 2) to assess whether protease inhibition can prevent E-C coupling failure following repeated tetani in these dystrophic mouse models. Excitation-contraction coupling was assessed using Fura-2 ratio, as an index of intracellular free Ca(2+) concentration, in response to electrical stimulation of single muscle fibers from the flexor digitorum brevis muscle. Resting Fura-2 ratio was higher in dystrophic compared with control (Con) fibers, but peak Fura-2 ratios during stimulation were similar in dystrophic and Con fibers. One hour after a series of repeated tetani, peak Fura-2 ratios were reduced by 30 ± 5.6%, 23 ± 2%, and 36 ± 3.1% in mdx, mdx/Utr(+/-), and mdx/Utr(-/-), respectively, with the greatest reduction in mdx/Utr(-/-) fibers (P < 0.05). Protease inhibition attenuated this decrease in peak Fura-2 ratio. These data indicate that E-C coupling impairment after repeated contractions is greatest in fibers lacking both dystrophin and utrophin and that prevention of protease activation can mitigate the prolonged E-C coupling impairment. These data further suggest that acute protease inhibition may be useful in reducing muscle weakness in DMD.
Collapse
Affiliation(s)
- Davi A G Mázala
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, Maryland; and
| | - Robert W Grange
- Department of Human Nutrition, Foods and Exercise, Virginia Polytechnic Institute and State University, Blacksburg, Virginia
| | - Eva R Chin
- Department of Kinesiology, School of Public Health, University of Maryland, College Park, Maryland; and
| |
Collapse
|
43
|
The need to more precisely define aspects of skeletal muscle regeneration. Int J Biochem Cell Biol 2014; 56:56-65. [PMID: 25242742 DOI: 10.1016/j.biocel.2014.09.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 09/04/2014] [Accepted: 09/08/2014] [Indexed: 12/11/2022]
Abstract
A more precise definition of the term 'skeletal muscle regeneration' is required to reduce confusion and misconceptions. In this paper the term is used only for events that follow myofibre necrosis, to result in myogenesis and new muscle formation: other key events include early inflammation and revascularisation, and later fibrosis and re-innervation. The term 'muscle regeneration' is sometimes used casually for situations that do not involve myonecrosis; such as restoration of muscle mass by hypertrophy after atrophy, and other forms of damage to muscle tissue components. These situations are excluded from the definition in this paper which is focussed on mammalian muscles with the long-term aim of clinical translation to enhance new muscle formation after acute or chronic injury or during surgery to replace whole muscles. The paper briefly outlines the cellular events involved in myogenesis during development and post-natal muscle growth, discusses the role of satellite cells in mature normal muscles, and the likely incidence of myofibre necrosis/regeneration in healthy ageing mammals (even when subjected to exercise). The importance of the various components of regeneration is outlined to emphasise that problems in each of these aspects can influence overall new muscle formation; thus care is needed for correct interpretation of altered kinetics. Various markers used to identify regenerating myofibres are critically discussed and, since these can all occur in other conditions, caution is required for accurate interpretation of these cellular events. Finally, clinical situations are outlined where there is a need to enhance skeletal muscle regeneration: these include acute and chronic injuries or transplantation with bioengineering to form new muscles, therapeutic approaches to muscular dystrophies, and comment on proposed stem cell therapies to reduce age-related loss of muscle mass and function. This article is part of a directed issue entitled: Regenerative Medicine: the challenge of translation.
Collapse
|
44
|
An HB, Zheng HC, Zhang L, Ma L, Liu ZY. Partial least squares based identification of Duchenne muscular dystrophy specific genes. J Zhejiang Univ Sci B 2014; 14:973-82. [PMID: 24190443 DOI: 10.1631/jzus.b1300060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Large-scale parallel gene expression analysis has provided a greater ease for investigating the underlying mechanisms of Duchenne muscular dystrophy (DMD). Previous studies typically implemented variance/regression analysis, which would be fundamentally flawed when unaccounted sources of variability in the arrays existed. Here we aim to identify genes that contribute to the pathology of DMD using partial least squares (PLS) based analysis. We carried out PLS-based analysis with two datasets downloaded from the Gene Expression Omnibus (GEO) database to identify genes contributing to the pathology of DMD. Except for the genes related to inflammation, muscle regeneration and extracellular matrix (ECM) modeling, we found some genes with high fold change, which have not been identified by previous studies, such as SRPX, GPNMB, SAT1, and LYZ. In addition, downregulation of the fatty acid metabolism pathway was found, which may be related to the progressive muscle wasting process. Our results provide a better understanding for the downstream mechanisms of DMD.
Collapse
Affiliation(s)
- Hui-bo An
- Department of Pathology, Children's Hospital, Shijiazhuang 050031, China; Department of Neurology, Children's Hospital, Shijiazhuang 050031, China
| | | | | | | | | |
Collapse
|
45
|
Brinkmeier H, Ohlendieck K. Chaperoning heat shock proteins: Proteomic analysis and relevance for normal and dystrophin-deficient muscle. Proteomics Clin Appl 2014; 8:875-95. [DOI: 10.1002/prca.201400015] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 04/24/2014] [Accepted: 05/28/2014] [Indexed: 12/15/2022]
Affiliation(s)
| | - Kay Ohlendieck
- Department of Biology; National University of Ireland; Maynooth Co. Kildare Ireland
| |
Collapse
|
46
|
Grounds MD. Therapies for sarcopenia and regeneration of old skeletal muscles: more a case of old tissue architecture than old stem cells. BIOARCHITECTURE 2014; 4:81-7. [PMID: 25101758 DOI: 10.4161/bioa.29668] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Age related loss of skeletal muscle mass and function (sarcopenia) reduces independence and the quality of life for individuals, and leads to falls and fractures with escalating health costs for the rapidly aging human population. Thus there is much interest in developing interventions to reduce sarcopenia. One area that has attracted recent attention is the proposed use of myogenic stem cells to improve regeneration of old muscles. This mini-review challenges the fundamental need for myogenic stem cell therapy for sarcopenia. It presents evidence that demonstrates the excellent capacity of myogenic stem cells from very old rodent and human muscles to form new muscles after experimental myofiber necrosis. The many factors required for successful muscle regeneration are considered with a strong focus on integration of components of old muscle bioarchitecture. The fundamental role of satellite cells in homeostasis of normal aging muscles and the incidence of endogenous regeneration in old muscles is questioned. These issues, combined with problems for clinical myogenic stem cell therapies for severe muscle diseases, raise fundamental concerns about the justification for myogenic stem cell therapy for sarcopenia.
Collapse
Affiliation(s)
- Miranda D Grounds
- School of Anatomy, Physiology and Human Biology; University of Western Australia; Crawley, Australia
| |
Collapse
|
47
|
Buttgereit A, Weber C, Friedrich O. A novel quantitative morphometry approach to assess regeneration in dystrophic skeletal muscle. Neuromuscul Disord 2014; 24:596-603. [DOI: 10.1016/j.nmd.2014.04.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 04/23/2014] [Indexed: 11/16/2022]
|
48
|
Faber RM, Hall JK, Chamberlain JS, Banks GB. Myofiber branching rather than myofiber hyperplasia contributes to muscle hypertrophy in mdx mice. Skelet Muscle 2014; 4:10. [PMID: 24910770 PMCID: PMC4047439 DOI: 10.1186/2044-5040-4-10] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Accepted: 05/06/2014] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Muscle hypertrophy in the mdx mouse model of Duchenne muscular dystrophy (DMD) can partially compensate for the loss of dystrophin by maintaining peak force production. Histopathology examination of the hypertrophic muscles suggests the hypertrophy primarily results from the addition of myofibers, and is accompanied by motor axon branching. However, it is unclear whether an increased number of innervated myofibers (myofiber hyperplasia) contribute to muscle hypertrophy in the mdx mice. METHODS To better understand the cellular mechanisms of muscle hypertrophy in mdx mice, we directly compared the temporal progression of the dystrophic pathology in the extensor digitorum longus (EDL) muscle to myofiber number, myofiber branching, and innervation, from 3 to 20 weeks of age. RESULTS We found that a 28% increase in the number of fibers in transverse sections of muscle correlated with a 31% increase in myofiber branching. Notably, the largest increases in myofiber number and myofiber branching occurred after 12 weeks of age when the proportion of myofibers with central nuclei had stabilized and the mdx mouse had reached maturity. The dystrophic pathology coincided with profound changes to innervation of the muscles that included temporary denervation of necrotic fibers, fragmentation of synapses, and ultra-terminal axon sprouting. However, there was little evidence of synapse formation in the mdx mice from 3 to 20 weeks of age. Only 4.4% of neuromuscular junctions extended ultra-terminal synapses, which failed to mature, and the total number of neuromuscular junctions remained constant. CONCLUSIONS Muscle hypertrophy in mdx mice results from myofiber branching rather than myofiber hyperplasia.
Collapse
Affiliation(s)
- Rachel M Faber
- Department of Neurology, University of Washington, Seattle, WA 98195-7720, USA
| | - John K Hall
- Department of Neurology, University of Washington, Seattle, WA 98195-7720, USA
| | - Jeffrey S Chamberlain
- Department of Neurology, University of Washington, Seattle, WA 98195-7720, USA ; Department of Biochemistry, University of Washington, Seattle, WA 98195-7720, USA ; Department of Medicine, University of Washington, Seattle, WA 98195-7720, USA
| | - Glen B Banks
- Department of Neurology, University of Washington, Seattle, WA 98195-7720, USA
| |
Collapse
|
49
|
Pichavant C, Pavlath GK. Incidence and severity of myofiber branching with regeneration and aging. Skelet Muscle 2014; 4:9. [PMID: 24855558 PMCID: PMC4030050 DOI: 10.1186/2044-5040-4-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 05/01/2014] [Indexed: 11/30/2022] Open
Abstract
Background Myofibers with an abnormal branching cytoarchitecture are commonly found in muscular dystrophy and in regenerated or aged nondystrophic muscles. Such branched myofibers from dystrophic mice are more susceptible to damage than unbranched myofibers in vitro, suggesting that muscles containing a high percentage of these myofibers are more prone to injury. Little is known about the regulation of myofiber branching. Methods To gain insights into the formation and fate of branched myofibers, we performed in-depth analyses of single myofibers isolated from dystrophic and nondystrophic (myotoxin-injured or aged) mouse muscles. The proportion of branched myofibers, the number of branches per myofiber and the morphology of the branches were assessed. Results Aged dystrophic mice exhibited the most severe myofiber branching as defined by the incidence of branched myofibers and the number of branches per myofiber, followed by myotoxin-injured, wild-type muscles and then aged wild-type muscles. In addition, the morphology of the branched myofibers differed among the various models. In response to either induced or ongoing muscle degeneration, branching was restricted to regenerated myofibers containing central nuclei. In myotoxin-injured muscles, the amount of branched myofibers remained stable over time. Conclusion We suggest that myofiber branching is a consequence of myofiber remodeling during muscle regeneration. Our present study lays valuable groundwork for identifying the molecular pathways leading to myofiber branching in dystrophy, trauma and aging. Decreasing myofiber branching in dystrophic patients may improve muscle resistance to mechanical stress.
Collapse
Affiliation(s)
- Christophe Pichavant
- Department of Pharmacology, Rollins Research Center, Emory University, 1510 Clifton Road, Atlanta, GA 30322, USA
| | - Grace K Pavlath
- Department of Pharmacology, Rollins Research Center, Emory University, 1510 Clifton Road, Atlanta, GA 30322, USA
| |
Collapse
|
50
|
Head SI, Houweling PJ, Chan S, Chen G, Hardeman EC. Properties of regenerated mouse extensor digitorum longus muscle following notexin injury. Exp Physiol 2014; 99:664-74. [PMID: 24414176 DOI: 10.1113/expphysiol.2013.077289] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Muscles of mdx mice are known to be more susceptible to contraction-induced damage than wild-type muscle. However, it is not clear whether this is because of dystrophin deficiency or because of the abnormal branching morphology of dystrophic muscle fibres. This distinction has an important bearing on our traditional understanding of the function of dystrophin as a mechanical stabilizer of the sarcolemma. In this study, we address the question: 'Does dystrophin-positive, regenerated muscle containing branched fibres also show an increased susceptibility to contraction-induced damage?' We produced a model of fibre branching by injecting dystrophin-positive extensor digitorum longus muscles with notexin. The regenerated muscle was examined at 21 days postinjection. Notexin-injected muscle contained 29% branched fibres and was not more susceptible to damage from mild eccentric contractions than contralateral saline-injected control muscle. Regenerated muscles also had greater mass, greater cross-sectional area and lower specific force than control muscles. We conclude that the number of branched fibres in this regenerated muscle is below the threshold needed to increase susceptibility to damage. However, it would serve as an ideal control for muscles of young mdx mice, allowing for clearer differentiation of the effects of dystrophin deficiency from the effects of fibre regeneration and morphology.
Collapse
Affiliation(s)
- S I Head
- * Faculty of Medicine, The University of New South Wales, Sydney, NSW 2052, Australia.
| | | | | | | | | |
Collapse
|