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Saclier M, Angelini G, Bonfanti C, Mura G, Temponi G, Messina G. Selective ablation of Nfix in macrophages attenuates muscular dystrophy by inhibiting fibro-adipogenic progenitor-dependent fibrosis. J Pathol 2022; 257:352-366. [PMID: 35297529 PMCID: PMC9322546 DOI: 10.1002/path.5895] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 02/24/2022] [Accepted: 03/15/2022] [Indexed: 11/10/2022]
Abstract
Muscular dystrophies are genetic diseases characterized by chronic inflammation and fibrosis. Macrophages are immune cells that sustain muscle regeneration upon acute injury but seem deleterious in the context of chronic muscle injury such as in muscular dystrophies. Here, we observed that the number of macrophages expressing the transcription factor Nfix increases in two distinct mouse models of muscular dystrophies. We showed that the deletion of Nfix in macrophages in dystrophic mice delays the establishment of fibrosis and muscle wasting, and increases grasp force. Macrophages lacking Nfix expressed more TNFα and less TGFβ1, thus promoting apoptosis of fibro‐adipogenic progenitors. Moreover, pharmacological treatment of dystrophic mice with a ROCK inhibitor accelerated fibrosis through the increase of Nfix expression by macrophages. Thus, we have identified Nfix as a macrophage profibrotic factor in muscular dystrophies, whose inhibition could be a therapeutic route to reduce severity of the dystrophic disease. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Affiliation(s)
| | | | - Chiara Bonfanti
- Department of Biosciences, University of Milan, Milan, Italy
| | - Giada Mura
- Department of Biosciences, University of Milan, Milan, Italy
| | - Giulia Temponi
- Department of Biosciences, University of Milan, Milan, Italy
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2
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Wilburn D, Ismaeel A, Machek S, Fletcher E, Koutakis P. Shared and distinct mechanisms of skeletal muscle atrophy: A narrative review. Ageing Res Rev 2021; 71:101463. [PMID: 34534682 DOI: 10.1016/j.arr.2021.101463] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/30/2021] [Accepted: 09/11/2021] [Indexed: 12/15/2022]
Abstract
Maintenance of skeletal muscle mass and function is an incredibly nuanced balance of anabolism and catabolism that can become distorted within different pathological conditions. In this paper we intend to discuss the distinct intracellular signaling events that regulate muscle protein atrophy for a given clinical occurrence. Aside from the common outcome of muscle deterioration, several conditions have at least one or more distinct mechanisms that creates unique intracellular environments that facilitate muscle loss. The subtle individuality to each of these given pathologies can provide both researchers and clinicians with specific targets of interest to further identify and increase the efficacy of medical treatments and interventions.
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Affiliation(s)
- Dylan Wilburn
- Department of Health, Human Performance, and Recreation, Baylor University, Waco, TX 76706, USA
| | - Ahmed Ismaeel
- Department of Biology, Baylor University, Waco, TX 76706, USA
| | - Steven Machek
- Department of Health, Human Performance, and Recreation, Baylor University, Waco, TX 76706, USA
| | - Emma Fletcher
- Department of Health, Human Performance, and Recreation, Baylor University, Waco, TX 76706, USA; Department of Biology, Baylor University, Waco, TX 76706, USA
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3
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Marine T, Marielle S, Graziella M, Fabio RMV. Macrophages in Skeletal Muscle Dystrophies, An Entangled Partner. J Neuromuscul Dis 2021; 9:1-23. [PMID: 34542080 PMCID: PMC8842758 DOI: 10.3233/jnd-210737] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
While skeletal muscle remodeling happens throughout life, diseases that result in its dysfunction are accountable for many deaths. Indeed, skeletal muscle is exceptionally capable to respond to stimuli modifying its homeostasis, such as in atrophy, hypertrophy, regeneration and repair. In particular conditions such as genetic diseases (muscular dystrophies), skeletal muscle’s capacity to remodel is strongly affected and undergoes continuous cycles of chronic damage. This induces scarring, fatty infiltration, as well as loss of contractibility and of the ability to generate force. In this context, inflammation, primarily mediated by macrophages, plays a central pathogenic role. Macrophages contribute as the primary regulators of inflammation during skeletal muscle regeneration, affecting tissue-resident cells such as myogenic cells and endothelial cells, but also fibro-adipogenic progenitors, which are the main source of the fibro fatty scar. During skeletal muscle regeneration their function is tightly orchestrated, while in dystrophies their fate is strongly disturbed, resulting in chronic inflammation. In this review, we will discuss the latest findings on the role of macrophages in skeletal muscle diseases, and how they are regulated.
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Affiliation(s)
- Theret Marine
- School of Biomedical Engineering, Department of Medical Genetics, University of British Columbia, Vancouver BC, Canada
| | - Saclier Marielle
- Department of Biosciences, University of Milan, via Celoria, Milan, Italy
| | - Messina Graziella
- Department of Biosciences, University of Milan, via Celoria, Milan, Italy
| | - Rossi M V Fabio
- School of Biomedical Engineering, Department of Medical Genetics, University of British Columbia, Vancouver BC, Canada
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4
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Yadava RS, Mandal M, Giese JM, Rigo F, Bennett CF, Mahadevan MS. Modeling muscle regeneration in RNA toxicity mice. Hum Mol Genet 2021; 30:1111-1130. [PMID: 33864373 PMCID: PMC8188403 DOI: 10.1093/hmg/ddab108] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/08/2021] [Accepted: 04/09/2021] [Indexed: 01/04/2023] Open
Abstract
RNA toxicity underlies the pathogenesis of disorders such as myotonic dystrophy type 1 (DM1). Muscular dystrophy is a key element of the pathology of DM1. The means by which RNA toxicity causes muscular dystrophy in DM1 is unclear. Here, we have used the DM200 mouse model of RNA toxicity due to the expression of a mutant DMPK 3′UTR mRNA to model the effects of RNA toxicity on muscle regeneration. Using a BaCl2-induced damage model, we find that RNA toxicity leads to decreased expression of PAX7, and decreased numbers of satellite cells, the stem cells of adult skeletal muscle (also known as MuSCs). This is associated with a delay in regenerative response, a lack of muscle fiber maturation and an inability to maintain a normal number of satellite cells. Repeated muscle damage also elicited key aspects of muscular dystrophy, including fat droplet deposition and increased fibrosis, and the results represent one of the first times to model these classic markers of dystrophic changes in the skeletal muscles of a mouse model of RNA toxicity. Using a ligand-conjugated antisense (LICA) oligonucleotide ASO targeting DMPK sequences for the first time in a mouse model of RNA toxicity in DM1, we find that treatment with IONIS 877864, which targets the DMPK 3′UTR mRNA, is efficacious in correcting the defects in regenerative response and the reductions in satellite cell numbers caused by RNA toxicity. These results demonstrate the possibilities for therapeutic interventions to mitigate the muscular dystrophy associated with RNA toxicity in DM1.
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Affiliation(s)
- Ramesh S Yadava
- Department of Pathology, University of Virginia, Charlottesville, VA 22908, USA
| | - Mahua Mandal
- Department of Pathology, University of Virginia, Charlottesville, VA 22908, USA
| | - Jack M Giese
- Department of Pathology, University of Virginia, Charlottesville, VA 22908, USA
| | - Frank Rigo
- Ionis Pharmaceuticals Inc., Carlsbad, CA 90210, USA
| | | | - Mani S Mahadevan
- Department of Pathology, University of Virginia, Charlottesville, VA 22908, USA
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5
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McDonald CM, Ramirez-Sanchez I, Oskarsson B, Joyce N, Aguilar C, Nicorici A, Dayan J, Goude E, Abresch RT, Villarreal F, Ceballos G, Perkins G, Dugar S, Schreiner G, Henricson EK. (-)-Epicatechin induces mitochondrial biogenesis and markers of muscle regeneration in adults with Becker muscular dystrophy. Muscle Nerve 2020; 63:239-249. [PMID: 33125736 PMCID: PMC7898288 DOI: 10.1002/mus.27108] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 10/22/2020] [Accepted: 10/25/2020] [Indexed: 12/31/2022]
Abstract
Introduction We conducted an open‐label study to examine the effects of the flavonoid (−)‐epicatechin in seven ambulatory adult patients with Becker muscular dystrophy (BMD). Methods Seven participants received (−)‐epicatechin 50 mg twice per day for 8 weeks. Pre‐ and postprocedures included biceps brachii biopsy to assess muscle structure and growth‐relevant endpoints by western blotting, mitochondria volume measurement, and cristae abundance by electron microscopy, graded exercise testing, and muscle strength and function tests. Results Western blotting showed significantly increased levels of enzymes modulating cellular bioenergetics (liver kinase B1 and 5′‐adenosine monophosphate–activated protein kinase). Peroxisome proliferator‐activated receptor gamma coactivator‐1alpha, a transcriptional coactivator of genes involved in mitochondrial biogenesis and cristae‐associated mitofilin levels, increased as did cristae abundance. Muscle and plasma follistatin increased significantly while myostatin decreased. Markers of skeletal muscle regeneration myogenin, myogenic regulatory factor‐5, myoblast determination protein 1, myocyte enhancer factor‐2, and structure‐associated proteins, including dysferlin, utrophin, and intracellular creatine kinase, also increased. Exercise testing demonstrated decreased heart rate, maximal oxygen consumption per kilogram, and plasma lactate levels at defined workloads. Tissue saturation index improved in resting and postexercise states. Discussion (−)‐Epicatechin, an exercise mimetic, appears to have short‐term positive effects on tissue biomarkers indicative of mitochondrial biogenesis and muscle regeneration, and produced improvements in graded exercise testing parameters in patients with BMD.
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Affiliation(s)
- Craig M McDonald
- Department of Physical Medicine and Rehabilitation, University of California Davis School of Medicine, Sacramento, California, USA
| | - Israel Ramirez-Sanchez
- Division of Cardiology, Department of Internal Medicine, University of California at San Diego, San Diego, California, USA.,Escuela Superior de Medicina, Seccion de Posgrado e Investigacion, del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Björn Oskarsson
- Department of Neurology, Mayo Clinic, Jacksonville, Florida, USA
| | - Nanette Joyce
- Department of Physical Medicine and Rehabilitation, University of California Davis School of Medicine, Sacramento, California, USA
| | - Candace Aguilar
- Department of Physical Medicine and Rehabilitation, University of California Davis School of Medicine, Sacramento, California, USA
| | - Alina Nicorici
- Department of Physical Medicine and Rehabilitation, University of California Davis School of Medicine, Sacramento, California, USA
| | - Jonathan Dayan
- Department of Physical Medicine and Rehabilitation, University of California Davis School of Medicine, Sacramento, California, USA
| | - Erica Goude
- Department of Physical Medicine and Rehabilitation, University of California Davis School of Medicine, Sacramento, California, USA
| | - R Ted Abresch
- Department of Physical Medicine and Rehabilitation, University of California Davis School of Medicine, Sacramento, California, USA
| | - Francisco Villarreal
- Division of Cardiology, Department of Internal Medicine, University of California at San Diego, San Diego, California, USA
| | - Guillermo Ceballos
- Escuela Superior de Medicina, Seccion de Posgrado e Investigacion, del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Guy Perkins
- Division of Cardiology, Department of Internal Medicine, University of California at San Diego, San Diego, California, USA
| | - Sundeep Dugar
- Epirium Bio, Inc (formerly Cardero Therapeutics, Inc), San Diego, California, USA
| | - George Schreiner
- Epirium Bio, Inc (formerly Cardero Therapeutics, Inc), San Diego, California, USA
| | - Erik K Henricson
- Department of Physical Medicine and Rehabilitation, University of California Davis School of Medicine, Sacramento, California, USA
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6
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White Z, Milad N, Tehrani AY, Chen WWH, Donen G, Sellers SL, Bernatchez P. Angiotensin II receptor blocker losartan exacerbates muscle damage and exhibits weak blood pressure-lowering activity in a dysferlin-null model of Limb-Girdle muscular dystrophy type 2B. PLoS One 2019; 14:e0220903. [PMID: 31404091 PMCID: PMC6690544 DOI: 10.1371/journal.pone.0220903] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 07/25/2019] [Indexed: 01/01/2023] Open
Abstract
There is no cure or beneficial management option for Limb-Girdle muscular dystrophy (MD) type 2B (LGMD2B). Losartan, a blood pressure (BP) lowering angiotensin II (AngII) receptor type 1 (ATR1) blocker (ARB) with unique anti-transforming growth factor-β (TGF-β) properties, can protect muscles in various types of MD such as Duchenne MD, suggesting a potential benefit for LGMD2B patients. Herein, we show in a mild, dysferlin-null mouse model of LGMD2B that losartan increased quadriceps muscle fibrosis (142%; P<0.0001). In a severe, atherogenic diet-fed model of LGMD2B recently described by our group, losartan further exacerbated dysferlin-null mouse muscle wasting in quadriceps and triceps brachii, two muscles typically affected by LGMD2B, by 40% and 51%, respectively (P<0.05). Lower TGF-β signalling was not observed with losartan, therefore plasma levels of atherogenic lipids known to aggravate LGMD2B severity were investigated. We report that losartan increased both plasma triglycerides and cholesterol concentrations in dysferlin-null mice. Other protective properties of losartan, such as increased nitric oxide release and BP lowering, were also reduced in the absence of dysferlin expression. Our data suggest that LGMD2B patients may show some resistance to the primary BP-lowering effects of losartan along with accelerated muscle wasting and dyslipidemia. Hence, we urge caution on the use of ARBs in this population as their ATR1 pathway may be dysfunctional.
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Affiliation(s)
- Zoe White
- University of British Columbia (UBC) Department of Anesthesiology, Pharmacology & Therapeutics, Vancouver, Canada
- UBC Centre for Heart Lung Innovation & St. Paul’s Hospital, Vancouver, Canada
- * E-mail: (ZW); (PB)
| | - Nadia Milad
- University of British Columbia (UBC) Department of Anesthesiology, Pharmacology & Therapeutics, Vancouver, Canada
- UBC Centre for Heart Lung Innovation & St. Paul’s Hospital, Vancouver, Canada
| | - Arash Y. Tehrani
- University of British Columbia (UBC) Department of Anesthesiology, Pharmacology & Therapeutics, Vancouver, Canada
- UBC Centre for Heart Lung Innovation & St. Paul’s Hospital, Vancouver, Canada
| | - William Wei-Han Chen
- University of British Columbia (UBC) Department of Anesthesiology, Pharmacology & Therapeutics, Vancouver, Canada
- UBC Centre for Heart Lung Innovation & St. Paul’s Hospital, Vancouver, Canada
| | - Graham Donen
- University of British Columbia (UBC) Department of Anesthesiology, Pharmacology & Therapeutics, Vancouver, Canada
- UBC Centre for Heart Lung Innovation & St. Paul’s Hospital, Vancouver, Canada
| | - Stephanie L. Sellers
- University of British Columbia (UBC) Department of Anesthesiology, Pharmacology & Therapeutics, Vancouver, Canada
- UBC Centre for Heart Lung Innovation & St. Paul’s Hospital, Vancouver, Canada
| | - Pascal Bernatchez
- University of British Columbia (UBC) Department of Anesthesiology, Pharmacology & Therapeutics, Vancouver, Canada
- UBC Centre for Heart Lung Innovation & St. Paul’s Hospital, Vancouver, Canada
- * E-mail: (ZW); (PB)
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7
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Abstract
Our understanding of satellite cells, now known to be the obligate stem cells of skeletal muscle, has increased dramatically in recent years due to the introduction of new molecular, genetic, and technical resources. In addition to their role in acute repair of damaged muscle, satellite cells are of interest in the fields of aging, exercise, neuromuscular disease, and stem cell therapy, and all of these applications have driven a dramatic increase in our understanding of the activity and potential of satellite cells. However, many fundamental questions of satellite cell biology remain to be answered, including their emergence as a specific lineage, the degree and significance of heterogeneity within the satellite cell population, the roles of their interactions with other resident and infiltrating cell types during homeostasis and regeneration, and the relative roles of intrinsic vs extrinsic factors that may contribute to satellite cell dysfunction in the context of aging or disease. This review will address the current state of these open questions in satellite cell biology.
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Affiliation(s)
- Ddw Cornelison
- University of Missouri, Columbia, MO, United States; Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States.
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8
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Albuquerque-Pontes GM, Casalechi HL, Tomazoni SS, Serra AJ, Ferreira CDSB, Brito RBDO, de Melo BL, Vanin AA, Monteiro KKDS, Dellê H, Frigo L, Marcos RL, de Carvalho PDTC, Leal-Junior ECP. Photobiomodulation therapy protects skeletal muscle and improves muscular function of mdx mice in a dose-dependent manner through modulation of dystrophin. Lasers Med Sci 2017; 33:755-764. [PMID: 29209866 DOI: 10.1007/s10103-017-2405-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Accepted: 11/28/2017] [Indexed: 01/12/2023]
Abstract
This study aimed to analyze the protective effects of photobiomodulation therapy (PBMT) with combination of low-level laser therapy (LLLT) and light emitting diode therapy (LEDT) on skeletal muscle tissue to delay dystrophy progression in mdx mice (DMD mdx ). To this aim, mice were randomly divided into five different experimental groups: wild type (WT), placebo-control (DMD mdx ), PBMT with doses of 1 J (DMD mdx ), 3 J (DMD mdx ), and 10 J (DMD mdx ). PBMT was performed employing a cluster probe with 9 diodes (1 x 905nm super-pulsed laser diode; 4 x 875nm infrared LEDs; and 4 x 640nm red LEDs, manufactured by Multi Radiance Medical®, Solon - OH, USA), 3 times a week for 14 weeks. PBMT was applied on a single point (tibialis anterior muscle-bilaterally). We analyzed functional performance, muscle morphology, and gene and protein expression of dystrophin. PBMT with a 10 J dose significantly improved (p < 0.001) functional performance compared to all other experimental groups. Muscle morphology was improved by all PBMT doses, with better outcomes with the 3 and 10 J doses. Gene expression of dystrophin was significantly increased with 3 J (p < 0.01) and 10 J (p < 0.01) doses when compared to placebo-control group. Regarding protein expression of dystrophin, 3 J (p < 0.001) and 10 J (p < 0.05) doses also significantly showed increase compared to placebo-control group. We conclude that PBMT can mainly preserve muscle morphology and improve muscular function of mdx mice through modulation of gene and protein expression of dystrophin. Furthermore, since PBMT is a non-pharmacological treatment which does not present side effects and is easy to handle, it can be seen as a promising tool for treating Duchenne's muscular dystrophy.
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Affiliation(s)
- Gianna Móes Albuquerque-Pontes
- Laboratory of Phototherapy in Sports and Exercise, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil.,Postgraduate Program in Biophotonics Applied to Health Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil
| | - Heliodora Leão Casalechi
- Laboratory of Phototherapy in Sports and Exercise, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil.,Postgraduate Program in Rehabilitation Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil
| | - Shaiane Silva Tomazoni
- Masters and Doctoral Programs in Physical Therapy, Universidade Cidade de São Paulo, São Paulo, Brazil
| | - Andrey Jorge Serra
- Postgraduate Program in Biophotonics Applied to Health Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil
| | | | | | - Brunno Lemes de Melo
- Postgraduate Program in Medicine, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
| | - Adriane Aver Vanin
- Laboratory of Phototherapy in Sports and Exercise, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil.,Postgraduate Program in Rehabilitation Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil
| | - Kadma Karênina Damasceno Soares Monteiro
- Laboratory of Phototherapy in Sports and Exercise, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil.,Postgraduate Program in Rehabilitation Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil
| | - Humberto Dellê
- Postgraduate Program in Medicine, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil
| | - Lucio Frigo
- Biological Sciences and Health Center, Cruzeiro do Sul University, São Paulo, Brazil
| | - Rodrigo Labat Marcos
- Postgraduate Program in Biophotonics Applied to Health Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil
| | - Paulo de Tarso Camillo de Carvalho
- Postgraduate Program in Biophotonics Applied to Health Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil.,Postgraduate Program in Rehabilitation Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil
| | - Ernesto Cesar Pinto Leal-Junior
- Laboratory of Phototherapy in Sports and Exercise, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil. .,Postgraduate Program in Rehabilitation Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil.
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9
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Pini V, Morgan JE, Muntoni F, O’Neill HC. Genome Editing and Muscle Stem Cells as a Therapeutic Tool for Muscular Dystrophies. CURRENT STEM CELL REPORTS 2017; 3:137-148. [PMID: 28616376 PMCID: PMC5445179 DOI: 10.1007/s40778-017-0076-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Purpose of Review Muscular dystrophies are a group of severe degenerative disorders characterized by muscle fiber degeneration and death. Therapies designed to restore muscle homeostasis and to replace dying fibers are being experimented, but none of those in clinical trials are suitable to permanently address individual gene mutation. The purpose of this review is to discuss genome editing tools such as CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated), which enable direct sequence alteration and could potentially be adopted to correct the genetic defect leading to muscle impairment. Recent Findings Recent findings show that advances in gene therapy, when combined with traditional viral vector-based approaches, are bringing the field of regenerative medicine closer to precision-based medicine. Summary The use of such programmable nucleases is proving beneficial for the creation of more accurate in vitro and in vivo disease models. Several gene and cell-therapy studies have been performed on satellite cells, the primary skeletal muscle stem cells involved in muscle regeneration. However, these have mainly been based on artificial replacement or augmentation of the missing protein. Satellite cells are a particularly appealing target to address these innovative technologies for the treatment of muscular dystrophies.
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Affiliation(s)
- Veronica Pini
- Molecular and Developmental Neurosciences Program, The Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH UK
| | - Jennifer E. Morgan
- Molecular and Developmental Neurosciences Program, The Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH UK
| | - Francesco Muntoni
- Molecular and Developmental Neurosciences Program, The Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH UK
| | - Helen C. O’Neill
- Embryology, IVF and Reproductive Genetics Group, Institute for Women’s Health, University College London, 86-96 Chenies Mews, London, WC1E 6HX UK
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10
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Li M, Andersson-Lendahl M, Sejersen T, Arner A. Knockdown of fast skeletal myosin-binding protein C in zebrafish results in a severe skeletal myopathy. ACTA ACUST UNITED AC 2016; 147:309-22. [PMID: 27022191 PMCID: PMC4810067 DOI: 10.1085/jgp.201511452] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 02/26/2016] [Indexed: 12/30/2022]
Abstract
MyBPC: A muscle protein for all seasons. Myosin-binding protein C (MyBPC) in the muscle sarcomere interacts with several contractile and structural proteins. Mutations in the cardiac isoform (MyBPC-3) in humans, or animal knockout, are associated with cardiomyopathy. Function of the fast skeletal isoform (MyBPC-2) in living muscles is less understood. This question was addressed using zebrafish models, combining gene expression data with functional analysis of contractility and small-angle x-ray diffraction measurements of filament structure. Fast skeletal MyBPC-2B, the major isoform, was knocked down by >50% using morpholino antisense nucleotides. These morphants exhibited a skeletal myopathy with elevated apoptosis and up-regulation of factors associated with muscle protein degradation. Morphant muscles had shorter sarcomeres with a broader length distribution, shorter actin filaments, and a wider interfilament spacing compared with controls, suggesting that fast skeletal MyBPC has a role in sarcomere assembly. Active force was reduced more than expected from the decrease in muscle size, suggesting that MyBPC-2 is required for optimal force generation at the cross-bridge level. The maximal shortening velocity was significantly increased in the MyBPC-2 morphants, but when related to the sarcomere length, the difference was smaller, reflecting that the decrease in MyBPC-2B content and the resulting myopathy were accompanied by only a minor influence on filament shortening kinetics. In the controls, equatorial patterns from small-angle x-ray scattering revealed that comparatively few cross-bridges are attached (as evaluated by the intensity ratio of the 11 and 10 equatorial reflections) during active contraction. X-ray scattering data from relaxed and contracting morphants were not significantly different from those in controls. However, the increase in the 11:10 intensity ratio in rigor was lower compared with that in controls, possibly reflecting effects of MyBPC on the cross-bridge interactions. In conclusion, lack of MyBPC-2 results in a severe skeletal myopathy with structural changes and muscle weakness.
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Affiliation(s)
- Mei Li
- Department of Physiology and Pharmacology, Department of Cell and Molecular Biology, and Department of Women's and Children's Health, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Monika Andersson-Lendahl
- Department of Physiology and Pharmacology, Department of Cell and Molecular Biology, and Department of Women's and Children's Health, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Thomas Sejersen
- Department of Physiology and Pharmacology, Department of Cell and Molecular Biology, and Department of Women's and Children's Health, Karolinska Institutet, SE 171 77 Stockholm, Sweden
| | - Anders Arner
- Department of Physiology and Pharmacology, Department of Cell and Molecular Biology, and Department of Women's and Children's Health, Karolinska Institutet, SE 171 77 Stockholm, Sweden
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11
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Abstract
PURPOSE OF REVIEW Recently, genetic pathways that modify the clinical severity of Duchenne muscular dystrophy (DMD) have been identified. The pathways uncovered as modifiers are useful to predict prognosis and also elucidate molecular signatures that can be manipulated therapeutically. RECENT FINDINGS Modifiers have been identified using combinations of transcriptome and genome profiling. Osteopontin, encoded by the SPP1 gene, was found using gene expression profiling. Latent TGFβ binding protein 4, encoding latent TGFβ binding protein 4 was initially discovered using a genome-wide screen in mice and then validated in cohorts of DMD patients. These two pathways converge in that they both regulate TGFβ. A third modifier, Anxa6 that specifies annexin A6, is a calcium binding protein that has been identified using mouse models, and regulates the injury pathway and sarcolemmal resealing. SUMMARY Genetic modifiers can serve as biomarkers for outcomes in DMD. Modifiers can alter strength and ambulation in muscular dystrophy, and these same features can be used as endpoints used in clinical trials. Moreover, because genetic modifiers can influence outcomes, these genetic markers should be considered when stratifying results in muscular dystrophy.
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Affiliation(s)
- Andy H Vo
- Committee on Development, Regeneration and Stem Cell Biology, Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, The University of Chicago, Chicago, Illinois, USA
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12
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Muscle Satellite Cells: Exploring the Basic Biology to Rule Them. Stem Cells Int 2016; 2016:1078686. [PMID: 27042182 PMCID: PMC4794588 DOI: 10.1155/2016/1078686] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 01/24/2016] [Indexed: 12/12/2022] Open
Abstract
Adult skeletal muscle is a postmitotic tissue with an enormous capacity to regenerate upon injury. This is accomplished by resident stem cells, named satellite cells, which were identified more than 50 years ago. Since their discovery, many researchers have been concentrating efforts to answer questions about their origin and role in muscle development, the way they contribute to muscle regeneration, and their potential to cell-based therapies. Satellite cells are maintained in a quiescent state and upon requirement are activated, proliferating, and fusing with other cells to form or repair myofibers. In addition, they are able to self-renew and replenish the stem pool. Every phase of satellite cell activity is highly regulated and orchestrated by many molecules and signaling pathways; the elucidation of players and mechanisms involved in satellite cell biology is of extreme importance, being the first step to expose the crucial points that could be modulated to extract the optimal response from these cells in therapeutic strategies. Here, we review the basic aspects about satellite cells biology and briefly discuss recent findings about therapeutic attempts, trying to raise questions about how basic biology could provide a solid scaffold to more successful use of these cells in clinics.
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Córdova G, Rochard A, Riquelme-Guzmán C, Cofré C, Scherman D, Bigey P, Brandan E. SMAD3 and SP1/SP3 Transcription Factors Collaborate to Regulate Connective Tissue Growth Factor Gene Expression in Myoblasts in Response to Transforming Growth Factor β. J Cell Biochem 2015; 116:1880-7. [DOI: 10.1002/jcb.25143] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 02/17/2015] [Indexed: 12/15/2022]
Affiliation(s)
- Gonzalo Córdova
- Laboratorio de Diferenciación Celular y Patología; Centro de Regulación Celular y Patología (CRCP); Departamento de Biología Celular y Molecular; Pontificia Universidad Católica de Chile; Santiago Chile
- Unité de Technologie Chimique et Biologique pour la Santé; CNRS, UMR8258; Paris F-75006 France
- INSERM U1022; Université Paris Descartes; ENSCP Chimie-ParisTech; Paris France
| | - Alice Rochard
- Unité de Technologie Chimique et Biologique pour la Santé; CNRS, UMR8258; Paris F-75006 France
- INSERM U1022; Université Paris Descartes; ENSCP Chimie-ParisTech; Paris France
| | - Camilo Riquelme-Guzmán
- Laboratorio de Diferenciación Celular y Patología; Centro de Regulación Celular y Patología (CRCP); Departamento de Biología Celular y Molecular; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Catalina Cofré
- Laboratorio de Diferenciación Celular y Patología; Centro de Regulación Celular y Patología (CRCP); Departamento de Biología Celular y Molecular; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Daniel Scherman
- Unité de Technologie Chimique et Biologique pour la Santé; CNRS, UMR8258; Paris F-75006 France
- INSERM U1022; Université Paris Descartes; ENSCP Chimie-ParisTech; Paris France
| | - Pascal Bigey
- Unité de Technologie Chimique et Biologique pour la Santé; CNRS, UMR8258; Paris F-75006 France
- INSERM U1022; Université Paris Descartes; ENSCP Chimie-ParisTech; Paris France
| | - Enrique Brandan
- Laboratorio de Diferenciación Celular y Patología; Centro de Regulación Celular y Patología (CRCP); Departamento de Biología Celular y Molecular; Pontificia Universidad Católica de Chile; Santiago Chile
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14
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Biressi S, Gopinath SD. The quasi-parallel lives of satellite cells and atrophying muscle. Front Aging Neurosci 2015; 7:140. [PMID: 26257645 PMCID: PMC4510774 DOI: 10.3389/fnagi.2015.00140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 07/06/2015] [Indexed: 12/25/2022] Open
Abstract
Skeletal muscle atrophy or wasting accompanies various chronic illnesses and the aging process, thereby reducing muscle function. One of the most important components contributing to effective muscle repair in postnatal organisms, the satellite cells (SCs), have recently become the focus of several studies examining factors participating in the atrophic process. We critically examine here the experimental evidence linking SC function with muscle loss in connection with various diseases as well as aging, and in the subsequent recovery process. Several recent reports have investigated the changes in SCs in terms of their differentiation and proliferative capacity in response to various atrophic stimuli. In this regard, we review the molecular changes within SCs that contribute to their dysfunctional status in atrophy, with the intention of shedding light on novel potential pharmacological targets to counteract the loss of muscle mass.
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Affiliation(s)
- Stefano Biressi
- Dulbecco Telethon Institute and Centre for Integrative Biology (CIBIO), University of TrentoTrento, Italy
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15
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Güttsches AK, Balakrishnan-Renuka A, Kley RA, Tegenthoff M, Brand-Saberi B, Vorgerd M. ATOH8: a novel marker in human muscle fiber regeneration. Histochem Cell Biol 2014; 143:443-52. [PMID: 25514850 DOI: 10.1007/s00418-014-1299-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2014] [Indexed: 01/20/2023]
Abstract
Regenerating muscle fibers emerge from quiescent satellite cells, which differentiate into mature multinuclear myofibers upon activation. It has recently been found that ATOH8, a bHLH transcription factor, is regulated during myogenic differentiation. In this study, expression and localization of ATOH8, the other well-described regeneration markers, vimentin, nestin and neonatal myosin, and the satellite cell marker Pax7 were analyzed on protein level in human myopathy samples by immunofluorescence studies. On mRNA level, expression levels of ATOH8 and vimentin were studied by quantitative real-time PCR. ATOH8 is expressed in activated satellite cells and proliferating myoblasts of human skeletal muscle tissue. Quantitative analyses of ATOH8+, Pax7+, vimentin+, nestin+ and neonatal myosin+ muscle fibers showed the highest amount of regenerating muscle fibers in inflammatory myopathies, followed by muscular dystrophy. The relative co-expression of ATOH8 with the above-mentioned markers did not vary among the disorders. These results show that the novel regeneration marker ATOH8 contributes to muscle cell differentiation in healthy and diseased human muscle tissue.
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Affiliation(s)
- Anne-K Güttsches
- Department of Neurology, Heimer-Institute at the BG University-Hospital Bergmannsheil GmbH, Ruhr University Bochum, Bürkle-de-la-Camp-Platz 1, 44789, Bochum, Germany,
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16
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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]
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Abstract
Neuromuscular diseases, which encompass disorders that affect muscle and its innervation, are highly heritable. Genetic diagnosis now frequently pinpoints the primary mutation responsible for a given neuromuscular disease. However, the results from genetic testing indicate that neuromuscular disease phenotypes may vary widely, even in individuals with the same primary disease-causing mutation. Clinical variability arises from both genetic and environmental factors. Genetic modifiers can now be identified using candidate gene as well as genomic approaches. The presence of genetic modifiers for neuromuscular disease helps define the clinical outcome and also highlights pathways of potential therapeutic utility. Herein, we will focus on single gene neuromuscular disorders, including muscular dystrophy, spinal muscular atrophy, and amyotrophic lateral sclerosis, and the methods that have been used to identify modifier genes. Animal models have been an invaluable resource for modifier gene discovery and subsequent mechanistic studies. Some modifiers, identified using animal models, have successfully translated to the human counterpart. Furthermore, in a few instances, modifier gene discovery has repetitively uncovered the same pathway, such as TGFβ signaling in muscular dystrophy, further emphasizing the relevance of that pathway. Knowledge of genetic factors that influence disease can have direct clinical applications for prognosis and predicted outcome.
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Affiliation(s)
- Kay-Marie Lamar
- Department of Human Genetics, Department of Medicine, Section of Cardiology, The University of Chicago, Chicago, IL, USA
| | - Elizabeth M McNally
- Department of Human Genetics, Department of Medicine, Section of Cardiology, The University of Chicago, Chicago, IL, USA
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18
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Ramadasan-Nair R, Gayathri N, Mishra S, Sunitha B, Mythri RB, Nalini A, Subbannayya Y, Harsha HC, Kolthur-Seetharam U, Srinivas Bharath MM. Mitochondrial alterations and oxidative stress in an acute transient mouse model of muscle degeneration: implications for muscular dystrophy and related muscle pathologies. J Biol Chem 2013; 289:485-509. [PMID: 24220031 DOI: 10.1074/jbc.m113.493270] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Muscular dystrophies (MDs) and inflammatory myopathies (IMs) are debilitating skeletal muscle disorders characterized by common pathological events including myodegeneration and inflammation. However, an experimental model representing both muscle pathologies and displaying most of the distinctive markers has not been characterized. We investigated the cardiotoxin (CTX)-mediated transient acute mouse model of muscle degeneration and compared the cardinal features with human MDs and IMs. The CTX model displayed degeneration, apoptosis, inflammation, loss of sarcolemmal complexes, sarcolemmal disruption, and ultrastructural changes characteristic of human MDs and IMs. Cell death caused by CTX involved calcium influx and mitochondrial damage both in murine C2C12 muscle cells and in mice. Mitochondrial proteomic analysis at the initial phase of degeneration in the model detected lowered expression of 80 mitochondrial proteins including subunits of respiratory complexes, ATP machinery, fatty acid metabolism, and Krebs cycle, which further decreased in expression during the peak degenerative phase. The mass spectrometry (MS) data were supported by enzyme assays, Western blot, and histochemistry. The CTX model also displayed markers of oxidative stress and a lowered glutathione reduced/oxidized ratio (GSH/GSSG) similar to MDs, human myopathies, and neurogenic atrophies. MS analysis identified 6 unique oxidized proteins from Duchenne muscular dystrophy samples (n = 6) (versus controls; n = 6), including two mitochondrial proteins. Interestingly, these mitochondrial proteins were down-regulated in the CTX model thereby linking oxidative stress and mitochondrial dysfunction. We conclude that mitochondrial alterations and oxidative damage significantly contribute to CTX-mediated muscle pathology with implications for human muscle diseases.
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Ieronimakis N, Hays AL, Janebodin K, Mahoney WM, Duffield JS, Majesky MW, Reyes M. Coronary adventitial cells are linked to perivascular cardiac fibrosis via TGFβ1 signaling in the mdx mouse model of Duchenne muscular dystrophy. J Mol Cell Cardiol 2013; 63:122-34. [PMID: 23911435 DOI: 10.1016/j.yjmcc.2013.07.014] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Revised: 06/20/2013] [Accepted: 07/23/2013] [Indexed: 01/12/2023]
Abstract
In Duchenne muscular dystrophy (DMD), progressive accumulation of cardiac fibrosis promotes heart failure. While the cellular origins of fibrosis in DMD hearts remain enigmatic, fibrotic tissue conspicuously forms near the coronary adventitia. Therefore, we sought to characterize the role of coronary adventitial cells in the formation of perivascular fibrosis. Utilizing the mdx model of DMD, we have identified a population of Sca1+, PDGFRα+, CD31-, and CD45- coronary adventitial cells responsible for perivascular fibrosis. Histopathology of dystrophic hearts revealed that Sca1+ cells extend from the adventitia and occupy regions of perivascular fibrosis. The number of Sca1+ adventitial cells increased two-fold in fibrotic mdx hearts vs. age matched wild-type hearts. Moreover, relative to Sca1-, PDGFRα+, CD31-, and CD45- cells and endothelial cells, Sca1+ adventitial cells FACS-sorted from mdx hearts expressed the highest level of Collagen1α1 and 3α1, Connective tissue growth factor, and Tgfβr1 transcripts. Surprisingly, mdx endothelial cells expressed the greatest level of the Tgfβ1 ligand. Utilizing Collagen1α1-GFP reporter mice, we confirmed that the majority of Sca1+ adventitial cells expressed type I collagen, an abundant component of cardiac fibrosis, in both wt (71%±4.1) and mdx (77%±3.5) hearts. In contrast, GFP+ interstitial fibroblasts were PDGFRα+ but negative for Sca1. Treatment of cultured Collagen1α1-GFP+ adventitial cells with TGFβ1 resulted in increased collagen synthesis, whereas pharmacological inhibition of TGFβR1 signaling reduced the fibrotic response. Therefore, perivascular cardiac fibrosis by coronary adventitial cells may be mediated by TGFβ1 signaling. Our results implicate coronary endothelial cells in mediating cardiac fibrosis via transmural TGFβ signaling, and suggest that the coronary adventitia is a promising target for developing novel anti-fibrotic therapies.
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Shin J, Tajrishi MM, Ogura Y, Kumar A. Wasting mechanisms in muscular dystrophy. Int J Biochem Cell Biol 2013; 45:2266-79. [PMID: 23669245 DOI: 10.1016/j.biocel.2013.05.001] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 04/29/2013] [Accepted: 05/02/2013] [Indexed: 12/11/2022]
Abstract
Muscular dystrophy is a group of more than 30 different clinical genetic disorders that are characterized by progressive skeletal muscle wasting and degeneration. Primary deficiency of specific extracellular matrix, sarcoplasmic, cytoskeletal, or nuclear membrane protein results in several secondary changes such as sarcolemmal instability, calcium influx, fiber necrosis, oxidative stress, inflammatory response, breakdown of extracellular matrix, and eventually fibrosis which leads to loss of ambulance and cardiac and respiratory failure. A number of molecular processes have now been identified which hasten disease progression in human patients and animal models of muscular dystrophy. Accumulating evidence further suggests that aberrant activation of several signaling pathways aggravate pathological cascades in dystrophic muscle. Although replacement of defective gene with wild-type is paramount to cure, management of secondary pathological changes has enormous potential to improving the quality of life and extending lifespan of muscular dystrophy patients. In this article, we have reviewed major cellular and molecular mechanisms leading to muscle wasting in muscular dystrophy. This article is part of a Directed Issue entitled: Molecular basis of muscle wasting.
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Affiliation(s)
- Jonghyun Shin
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
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21
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The involvement of collagen triple helix repeat containing 1 in muscular dystrophies. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 182:905-16. [PMID: 23274062 DOI: 10.1016/j.ajpath.2012.11.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Revised: 10/15/2012] [Accepted: 11/01/2012] [Indexed: 11/20/2022]
Abstract
Fibrosis is the main complication of muscular dystrophies. We identified collagen triple helix repeat containing 1 (Cthrc1) in skeletal and cardiac muscles of mice, representing Duchenne and congenital muscle dystrophies (DMD and CMD, respectively), and dysferlinopathy. In all of the mice, Cthrc1 was associated with high collagen type I levels; no Cthrc1 or collagen was observed in muscles of control mice. High levels of Cthrc1 were also observed in biopsy specimens from patients with DMD, in whom they were reversibly correlated with that of β-dystroglycan, whereas collagen type I levels were elevated in all patients with DMD. At the muscle sites where collagen and Cthrc1 were adjacent, collagen fibers appeared smaller, suggesting involvement of Cthrc1 in collagen turnover. Halofuginone, an inhibitor of Smad3 phosphorylation downstream of the transforming growth factor-β signaling, reduced Cthrc1 levels in skeletal and cardiac muscles of mice, representing DMD, CMD, and dysferlinopathy. The myofibroblasts infiltrating the dystrophic muscles of the murine models of DMD, CMD, and dysferlinopathy were the source of Cthrc1. Transforming growth factor-β did not affect Cthrc1 levels in the mdx fibroblasts but decreased them in the control fibroblasts, in association with increased migration of mdx fibroblasts and dystrophic muscle invasion by myofibroblasts. To our knowledge, this is the first demonstration of Cthrc1 as a marker of the severity of the disease progression in the dystrophic muscles, and as a possible target for therapy.
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