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Ashokkumar H, Bhatia SU, Azhagar Nambi Santhi V, Kumar R. Autosomal recessive limb girdle muscular dystrophy-type 5 (LGMDR-5). BMJ Case Rep 2024; 17:e260321. [PMID: 38802251 DOI: 10.1136/bcr-2024-260321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024] Open
Abstract
Limb-girdle muscular dystrophy (LGMD) comprises a heterogeneous group of rare genetic disorders characterised by progressive weakness and atrophy of the muscles, primarily affecting the pelvic and shoulder girdles. A developmentally normal, early adolescent male presented with complaints of difficulty in using all four limbs with a waddling gait, gradually progressive over the last 5 years. No significant family history was noted. We noticed thinning and atrophy of both upper and lower limbs, proximal more than distal, associated with wasting, hypotonia and decreased power in all four limbs. Gower's sign was positive. The winging of the scapula was present. All deep tendon reflexes and superficial reflexes were present with flexor response in both plantars. The sensory system was normal. An initial diagnosis of muscular dystrophy was made and confirmed with clinical exome sequencing, which showed a pathogenic variant indicating a very rare type of autosomal recessive LGMD. This disease was previously named LGMD2C and has now been renamed under LGMDR5.
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Affiliation(s)
- Hamritha Ashokkumar
- Department of Paediatrics, SIMATS Deemed University, Saveetha Medical College and Hospital, Chennai, Tamil Nadu, India
| | - Sakshi Upendra Bhatia
- Department of Paediatrics, SIMATS Deemed University, Saveetha Medical College and Hospital, Chennai, Tamil Nadu, India
| | | | - Radha Kumar
- Department of Paediatrics, SIMATS Deemed University, Saveetha Medical College and Hospital, Chennai, Tamil Nadu, India
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2
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Patel KK, Venkatesan C, Abdelhalim H, Zeeshan S, Arima Y, Linna-Kuosmanen S, Ahmed Z. Genomic approaches to identify and investigate genes associated with atrial fibrillation and heart failure susceptibility. Hum Genomics 2023; 17:47. [PMID: 37270590 DOI: 10.1186/s40246-023-00498-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 05/31/2023] [Indexed: 06/05/2023] Open
Abstract
Atrial fibrillation (AF) and heart failure (HF) contribute to about 45% of all cardiovascular disease (CVD) deaths in the USA and around the globe. Due to the complex nature, progression, inherent genetic makeup, and heterogeneity of CVDs, personalized treatments are believed to be critical. To improve the deciphering of CVD mechanisms, we need to deeply investigate well-known and identify novel genes that are responsible for CVD development. With the advancements in sequencing technologies, genomic data have been generated at an unprecedented pace to foster translational research. Correct application of bioinformatics using genomic data holds the potential to reveal the genetic underpinnings of various health conditions. It can help in the identification of causal variants for AF, HF, and other CVDs by moving beyond the one-gene one-disease model through the integration of common and rare variant association, the expressed genome, and characterization of comorbidities and phenotypic traits derived from the clinical information. In this study, we examined and discussed variable genomic approaches investigating genes associated with AF, HF, and other CVDs. We collected, reviewed, and compared high-quality scientific literature published between 2009 and 2022 and accessible through PubMed/NCBI. While selecting relevant literature, we mainly focused on identifying genomic approaches involving the integration of genomic data; analysis of common and rare genetic variants; metadata and phenotypic details; and multi-ethnic studies including individuals from ethnic minorities, and European, Asian, and American ancestries. We found 190 genes associated with AF and 26 genes linked to HF. Seven genes had implications in both AF and HF, which are SYNPO2L, TTN, MTSS1, SCN5A, PITX2, KLHL3, and AGAP5. We listed our conclusion, which include detailed information about genes and SNPs associated with AF and HF.
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Affiliation(s)
- Kush Ketan Patel
- Rutgers Institute for Health, Health Care Policy and Aging Research, Rutgers University, 112 Paterson St, New Brunswick, NJ, USA
| | - Cynthia Venkatesan
- Rutgers Institute for Health, Health Care Policy and Aging Research, Rutgers University, 112 Paterson St, New Brunswick, NJ, USA
| | - Habiba Abdelhalim
- Rutgers Institute for Health, Health Care Policy and Aging Research, Rutgers University, 112 Paterson St, New Brunswick, NJ, USA
| | - Saman Zeeshan
- Rutgers Cancer Institute of New Jersey, Rutgers University, 195 Little Albany St, New Brunswick, NJ, USA
| | - Yuichiro Arima
- Developmental Cardiology Laboratory, International Research Center for Medical Sciences, Kumamoto University, 2-2-1 Honjo, Kumamoto City, Kumamoto, Japan
| | - Suvi Linna-Kuosmanen
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, 70211, Kuopio, Finland
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Zeeshan Ahmed
- Department of Genetics and Genome Sciences, UConn Health, 400 Farmington Ave, Farmington, CT, USA.
- Department of Medicine, Robert Wood Johnson Medical School, Rutgers Biomedical and Health Sciences, 125 Paterson St, New Brunswick, NJ, USA.
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Verebi C, Caumes R, Chantot-Bastaraud S, Deburgrave N, Orhant L, Vaucouleur N, Cuisset L, Bienvenu T, Leturcq F, Nectoux J. How a paternal uniparental isodisomy of chromosome 17 leads to autosomal recessive limb-girdle muscular dystrophy-3. Neuromuscul Disord 2023; 33:367-370. [PMID: 36996638 DOI: 10.1016/j.nmd.2023.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/01/2023] [Accepted: 03/14/2023] [Indexed: 03/17/2023]
Abstract
Uniparental isodisomy is a condition where both chromosomes of a pair are inherited from one parental homologue. If a deleterious variant is present on the duplicated chromosome, its homozygosity can reveal an autosomal recessive disorder in the offspring of a heterozygous carrier. Limb-girdle muscular dystrophy (LGMD) R3 is an autosomal recessive inherited disease that is associated with alpha-sarcoglycan gene (SGCA) variants. We report the first published case of LGMDR3 due to a homozygous variant in SGCA unmasked by uniparental isodisomy. The patient is an 8-year-old who experienced delayed motor milestones but normal cognitive development. He presented with muscle pain and elevated plasma creatine kinase. Sequencing of the SGCA gene showed a homozygous pathogenic variant. Parents were not related and only the father was heterozygous for the pathogenic variant. A chromosomal microarray revealed a complete chromosome 17 copy number neutral loss of heterozygosity encompassing SGCA, indicating paternal uniparental isodisomy.
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4
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Inherited myopathies in the Middle East and North Africa. GENE REPORTS 2022. [DOI: 10.1016/j.genrep.2022.101674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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5
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Abstract
Muscular dystrophies are a group of genetic disorders characterized by varying degrees of progressive muscle weakness and degeneration. They are clinically and genetically heterogeneous but share the common histological features of dystrophic muscle. There is currently no cure for muscular dystrophies, which is of particular concern for the more disabling and/or lethal forms of the disease. Through the years, several therapies have encouragingly been developed for muscular dystrophies and include genetic, cellular, and pharmacological approaches. In this chapter, we undertake a comprehensive exploration of muscular dystrophy therapeutics under current development. Our review includes antisense therapy, CRISPR, gene replacement, cell therapy, nonsense suppression, and disease-modifying small molecule compounds.
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Groh WJ, Bhakta D, Tomaselli GF, Aleong RG, Teixeira RA, Amato A, Asirvatham SJ, Cha YM, Corrado D, Duboc D, Goldberger ZD, Horie M, Hornyak JE, Jefferies JL, Kääb S, Kalman JM, Kertesz NJ, Lakdawala NK, Lambiase PD, Lubitz SA, McMillan HJ, McNally EM, Milone M, Namboodiri N, Nazarian S, Patton KK, Russo V, Sacher F, Santangeli P, Shen WK, Sobral Filho DC, Stambler BS, Stöllberger C, Wahbi K, Wehrens XHT, Weiner MM, Wheeler MT, Zeppenfeld K. 2022 HRS expert consensus statement on evaluation and management of arrhythmic risk in neuromuscular disorders. Heart Rhythm 2022; 19:e61-e120. [PMID: 35500790 DOI: 10.1016/j.hrthm.2022.04.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 04/21/2022] [Indexed: 11/04/2022]
Abstract
This international multidisciplinary document is intended to guide electrophysiologists, cardiologists, other clinicians, and health care professionals in caring for patients with arrhythmic complications of neuromuscular disorders (NMDs). The document presents an overview of arrhythmias in NMDs followed by detailed sections on specific disorders: Duchenne muscular dystrophy, Becker muscular dystrophy, and limb-girdle muscular dystrophy type 2; myotonic dystrophy type 1 and type 2; Emery-Dreifuss muscular dystrophy and limb-girdle muscular dystrophy type 1B; facioscapulohumeral muscular dystrophy; and mitochondrial myopathies, including Friedreich ataxia and Kearns-Sayre syndrome, with an emphasis on managing arrhythmic cardiac manifestations. End-of-life management of arrhythmias in patients with NMDs is also covered. The document sections were drafted by the writing committee members according to their area of expertise. The recommendations represent the consensus opinion of the expert writing group, graded by class of recommendation and level of evidence utilizing defined criteria. The recommendations were made available for public comment; the document underwent review by the Heart Rhythm Society Scientific and Clinical Documents Committee and external review and endorsement by the partner and collaborating societies. Changes were incorporated based on these reviews. By using a breadth of accumulated available evidence, the document is designed to provide practical and actionable clinical information and recommendations for the diagnosis and management of arrhythmias and thus improve the care of patients with NMDs.
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Affiliation(s)
- William J Groh
- Ralph H. Johnson VA Medical Center and Medical University of South Carolina, Charleston, South Carolina
| | - Deepak Bhakta
- Indiana University School of Medicine, Indianapolis, Indiana
| | | | | | | | - Anthony Amato
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | | | | | - Domenico Corrado
- Department of Cardiac, Thoracic, and Vascular Sciences, University of Padova, Padova, Italy
| | - Denis Duboc
- Cardiology Department, Hôpital Cochin, AP-HP, Université de Paris, Paris, France
| | - Zachary D Goldberger
- University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | - Minoru Horie
- Shiga University of Medical Sciences, Otsu, Japan
| | | | | | - Stefan Kääb
- Department of Medicine I, University Hospital, LMU Munich, Munich, Germany
| | - Jonathan M Kalman
- Royal Melbourne Hospital and University of Melbourne, Melbourne, Victoria, Australia
| | | | - Neal K Lakdawala
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Pier D Lambiase
- Barts Heart Centre, St Bartholomew's Hospital, University College London, and St Bartholomew's Hospital London, London, United Kingdom
| | | | - Hugh J McMillan
- Montreal Children's Hospital, McGill University, Montreal, Quebec, Canada
| | | | | | - Narayanan Namboodiri
- Sree Chitra Institute for Medical Sciences and Technology, Thiruvananthapuram, India
| | | | | | | | - Frederic Sacher
- Bordeaux University Hospital, LIRYC Institute, Bordeaux, France
| | | | | | | | | | - Claudia Stöllberger
- Second Medical Department with Cardiology and Intensive Care Medicine, Klinik Landstraße, Vienna, Austria
| | - Karim Wahbi
- Cardiology Department, Hôpital Cochin, AP-HP, Université de Paris, Paris, France
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Zanotti S, Magri F, Poggetti F, Ripolone M, Velardo D, Fortunato F, Ciscato P, Moggio M, Corti S, Comi GP, Sciacco M. Immunofluorescence signal intensity measurements as a semi-quantitative tool to assess sarcoglycan complex expression in muscle biopsy. Eur J Histochem 2022; 66. [PMID: 36047345 PMCID: PMC9471914 DOI: 10.4081/ejh.2022.3418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 06/20/2022] [Indexed: 11/25/2022] Open
Abstract
Sarcoglycanopathies are highly heterogeneous in terms of disease progression, muscular weakness, loss of ambulation and cardiac/respiratory involvement. Their clinical severity usually correlates with the residual protein amount, which makes protein quantification extremely relevant. Sarcoglycanopathy diagnosis is genetic, but skeletal muscle analysis - by both immunohistochemistry and Western blot (WB) - is still mandatory to establish the correct diagnostic process. Unfortunately, however, WB analysis cannot be performed if the bioptic specimen is scarce. This study provides a sensitive tool for semi-quantification of residual amount of sarcoglycans in patients affected by sarcoglycanopathies, based on immunofluorescence staining on skeletal muscle sections, image acquisition and software elaboration. We applied this method to eleven sarcoglycanopathies, seven Becker muscular dystrophies, as pathological control group, and four age-matched controls. Fluorescence data showed a significantly reduced expression of the mutated sarcoglycan in all patients when compared to their respective age-matched healthy controls, and a variable reduction of the other sarcoglycans. The reduction is due to the effect of gene mutation and not to the increasing age of controls. Fluorescence normalized data analyzed in relation to the age of onset of the disease, showed a negative correlation of a-sarcoglycan fluorescence signal vs fibrosis in patients with an early age of onset and a negative correlation between d-sarcoglycan signal and fibrosis in both intermediate and late age of onset groups. The availability of a method that allows objective quantification of the sarcolemmal proteins, faster and less consuming than WB analysis and able to detect low residual sarcoglycan expression with great sensitivity, proves useful also in view of possible inferences on disease prognosis. The proposed method could be employed also to monitor the efficacy of therapeutic interventions and during clinical trials.
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Affiliation(s)
- Simona Zanotti
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Francesca Magri
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Francesca Poggetti
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Michela Ripolone
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Daniele Velardo
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Francesco Fortunato
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Patrizia Ciscato
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Maurizio Moggio
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Stefania Corti
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Giacomo Pietro Comi
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
| | - Monica Sciacco
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan.
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Hoch L, Bourg N, Degrugillier F, Bruge C, Benabides M, Pellier E, Tournois J, Mahé G, Maignan N, Dawe J, Georges M, Papazian D, Subramanian N, Simon S, Fanen P, Delevoye C, Richard I, Nissan X. Dual Blockade of Misfolded Alpha-Sarcoglycan Degradation by Bortezomib and Givinostat Combination. Front Pharmacol 2022; 13:856804. [PMID: 35571097 PMCID: PMC9093689 DOI: 10.3389/fphar.2022.856804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 04/04/2022] [Indexed: 11/13/2022] Open
Abstract
Limb-girdle muscular dystrophy type R3 (LGMD R3) is a rare genetic disorder characterized by a progressive proximal muscle weakness and caused by mutations in the SGCA gene encoding alpha-sarcoglycan (α-SG). Here, we report the results of a mechanistic screening ascertaining the molecular mechanisms involved in the degradation of the most prevalent misfolded R77C-α-SG protein. We performed a combinatorial study to identify drugs potentializing the effect of a low dose of the proteasome inhibitor bortezomib on the R77C-α-SG degradation inhibition. Analysis of the screening associated to artificial intelligence-based predictive ADMET characterization of the hits led to identification of the HDAC inhibitor givinostat as potential therapeutical candidate. Functional characterization revealed that givinostat effect was related to autophagic pathway inhibition, unveiling new theories concerning degradation pathways of misfolded SG proteins. Beyond the identification of a new therapeutic option for LGMD R3 patients, our results shed light on the potential repurposing of givinostat for the treatment of other genetic diseases sharing similar protein degradation defects such as LGMD R5 and cystic fibrosis.
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Affiliation(s)
- Lucile Hoch
- CECS, I-Stem, Corbeil-Essonne, France.,INSERM U861, I-Stem, Corbeil-Essonne, France.,UEVE U861, I-Stem, Corbeil-Essonne, France
| | - Nathalie Bourg
- INTEGRARE, Genethon, Inserm, Univ Evry, Université Paris-Saclay, Evry, France
| | | | - Céline Bruge
- CECS, I-Stem, Corbeil-Essonne, France.,INSERM U861, I-Stem, Corbeil-Essonne, France.,UEVE U861, I-Stem, Corbeil-Essonne, France
| | - Manon Benabides
- CECS, I-Stem, Corbeil-Essonne, France.,INSERM U861, I-Stem, Corbeil-Essonne, France.,UEVE U861, I-Stem, Corbeil-Essonne, France
| | - Emilie Pellier
- CECS, I-Stem, Corbeil-Essonne, France.,INSERM U861, I-Stem, Corbeil-Essonne, France.,UEVE U861, I-Stem, Corbeil-Essonne, France
| | - Johana Tournois
- CECS, I-Stem, Corbeil-Essonne, France.,INSERM U861, I-Stem, Corbeil-Essonne, France.,UEVE U861, I-Stem, Corbeil-Essonne, France
| | - Gurvan Mahé
- CECS, I-Stem, Corbeil-Essonne, France.,INSERM U861, I-Stem, Corbeil-Essonne, France.,UEVE U861, I-Stem, Corbeil-Essonne, France
| | | | | | | | | | | | | | - Pascale Fanen
- Université Paris Est Creteil, INSERM, IMRB, Créteil, France.,Département de Genetique, DMU Biologie-Pathologie, GH Mondor-A. Chenevier, AP-HP, Creteil, France
| | - Cédric Delevoye
- Institut Curie, PSL Research University, CNRS, UMR144, Structure and Membrane Compartments, Paris, France.,Institut Curie, PSL Research University, CNRS, UMR144, Cell and Tissue Imaging Facility (PICT-IBiSA), Paris, France
| | - Isabelle Richard
- INTEGRARE, Genethon, Inserm, Univ Evry, Université Paris-Saclay, Evry, France
| | - Xavier Nissan
- CECS, I-Stem, Corbeil-Essonne, France.,INSERM U861, I-Stem, Corbeil-Essonne, France.,UEVE U861, I-Stem, Corbeil-Essonne, France
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Advanced Gene-Targeting Therapies for Motor Neuron Diseases and Muscular Dystrophies. Int J Mol Sci 2022; 23:ijms23094824. [PMID: 35563214 PMCID: PMC9101723 DOI: 10.3390/ijms23094824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/22/2022] [Accepted: 04/25/2022] [Indexed: 12/19/2022] Open
Abstract
Gene therapy is a revolutionary, cutting-edge approach to permanently ameliorate or amend many neuromuscular diseases by targeting their genetic origins. Motor neuron diseases and muscular dystrophies, whose genetic causes are well known, are the frontiers of this research revolution. Several genetic treatments, with diverse mechanisms of action and delivery methods, have been approved during the past decade and have demonstrated remarkable results. However, despite the high number of genetic treatments studied preclinically, those that have been advanced to clinical trials are significantly fewer. The most clinically advanced treatments include adeno-associated virus gene replacement therapy, antisense oligonucleotides, and RNA interference. This review provides a comprehensive overview of the advanced gene therapies for motor neuron diseases (i.e., amyotrophic lateral sclerosis and spinal muscular atrophy) and muscular dystrophies (i.e., Duchenne muscular dystrophy, limb-girdle muscular dystrophy, and myotonic dystrophy) tested in clinical trials. Emphasis has been placed on those methods that are a few steps away from their authoritative approval.
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Carson L, Merrick D. Genotype-phenotype correlations in alpha-sarcoglycanopathy: a systematic review. Ir J Med Sci 2022; 191:2743-2750. [PMID: 35040091 DOI: 10.1007/s11845-021-02855-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 10/27/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Mutations in the alpha-sarcoglycan gene cause limb-girdle muscular dystrophy 2D, an autosomal recessive muscle wasting disorder primarily affecting the muscles of the shoulder and pelvic girdles. To date, no previous study has collated all known mutations in alpha-sarcoglycan and mapped these to the associated phenotypes. AIMS To examine for correlations between mutation locations, or mutation type, and the phenotype caused in all reported mutations in alpha-sarcoglycan. METHODS We present a systematic literature review examining correlations between mutation locations, or mutation type, and the phenotype caused in all reported cases of limb-girdle muscular dystrophy 2D. RESULTS From 134 unique genotypes collated, a strong prevalence of missense mutations (64% of all unique mutations) was found in this gene. Mutation hotspots were noted in exon three and the extracellular domain, with mutation densities varying significantly between both exons and protein domains (p ≤ 0.01). All compound heterozygous limb-girdle muscular dystrophy 2D patients with cardiac involvement contained at least one mutation in exon three, a novel finding. All non-sense mutations in alpha-sarcoglycan give a severe phenotype, as do genotypes involving a combination of exons four and five. This study confirms on a large, diverse cohort the extremely high prevalence of the c.229C > T mutation. CONCLUSIONS This study demonstrates the vast variation in disease severity seen between patients possessing the same mutation, highlighting the difficulty identifying genotype-phenotype correlations in this condition. Novel findings including the involvement of exon three in all compound heterozygous patients who suffered from cardiomyopathy, and the severity of mutations involving exons four and five may help to guide investigations and therapeutic decisions in an era of personalised medicine.
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Affiliation(s)
- Luke Carson
- School of Life Sciences, University of Nottingham, Nottingham, UK.
| | - Deborah Merrick
- School of Life Sciences, University of Nottingham, Nottingham, UK
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11
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Abstract
The limb-girdle muscular dystrophies (LGMD) are a collection of genetic diseases united in their phenotypical expression of pelvic and shoulder area weakness and wasting. More than 30 subtypes have been identified, five dominant and 26 recessive. The increase in the characterization of new genotypes in the family of LGMDs further adds to the heterogeneity of the disease. Meanwhile, better understanding of the phenotype led to the reconsideration of the disease definition, which resulted in eight old subtypes to be no longer recognized officially as LGMD and five new diseases to be added to the LGMD family. The unique variabilities of LGMD stem from genetic mutations, which then lead to protein and ultimately muscle dysfunction. Herein, we review the LGMD pathway, starting with the genetic mutations that encode proteins involved in muscle maintenance and repair, and including the genotype–phenotype relationship of the disease, the epidemiology, disease progression, burden of illness, and emerging treatments.
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Bazrafshan S, Kushlaf H, Kakroo M, Quinlan J, Becker RC, Sadayappan S. Genetic Modifiers of Hereditary Neuromuscular Disorders and Cardiomyopathy. Cells 2021; 10:cells10020349. [PMID: 33567613 PMCID: PMC7915259 DOI: 10.3390/cells10020349] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/26/2021] [Accepted: 02/03/2021] [Indexed: 12/18/2022] Open
Abstract
Novel genetic variants exist in patients with hereditary neuromuscular disorders (NMD), including muscular dystrophy. These patients also develop cardiac manifestations. However, the association between these gene variants and cardiac abnormalities is understudied. To determine genetic modifiers and features of cardiac disease in NMD patients, we have reviewed electronic medical records of 651 patients referred to the Muscular Dystrophy Association Care Center at the University of Cincinnati and characterized the clinical phenotype of 14 patients correlating with their next-generation sequencing data. The data were retrieved from the electronic medical records of the 14 patients included in the current study and comprised neurologic and cardiac phenotype and genetic reports which included comparative genomic hybridization array and NGS. Novel associations were uncovered in the following eight patients diagnosed with Limb-girdle Muscular Dystrophy, Bethlem Myopathy, Necrotizing Myopathy, Charcot-Marie-Tooth Disease, Peripheral Polyneuropathy, and Valosin-containing Protein-related Myopathy. Mutations in COL6A1, COL6A3, SGCA, SYNE1, FKTN, PLEKHG5, ANO5, and SMCHD1 genes were the most common, and the associated cardiac features included bundle branch blocks, ventricular chamber dilation, septal thickening, and increased outflow track gradients. Our observations suggest that features of cardiac disease and modifying gene mutations in patients with NMD require further investigation to better characterize genotype–phenotype relationships.
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Affiliation(s)
- Sholeh Bazrafshan
- Heart, Lung and Vascular Institute, Division of Cardiovascular Health and Disease, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (S.B.); (M.K.); (R.C.B.)
| | - Hani Kushlaf
- Department of Neurology and Rehabilitation Medicine, Neuromuscular Center, University of Cincinnati Gardner Neuroscience Institute, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (H.K.); (J.Q.)
| | - Mashhood Kakroo
- Heart, Lung and Vascular Institute, Division of Cardiovascular Health and Disease, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (S.B.); (M.K.); (R.C.B.)
| | - John Quinlan
- Department of Neurology and Rehabilitation Medicine, Neuromuscular Center, University of Cincinnati Gardner Neuroscience Institute, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (H.K.); (J.Q.)
| | - Richard C. Becker
- Heart, Lung and Vascular Institute, Division of Cardiovascular Health and Disease, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (S.B.); (M.K.); (R.C.B.)
| | - Sakthivel Sadayappan
- Heart, Lung and Vascular Institute, Division of Cardiovascular Health and Disease, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA; (S.B.); (M.K.); (R.C.B.)
- Correspondence: ; Tel.: +1-513-558-7498
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13
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Gibbs EM, McCourt JL, Shin KM, Hammond KG, Marshall JL, Crosbie RH. Loss of sarcospan exacerbates pathology in mdx mice, but does not affect utrophin amelioration of disease. Hum Mol Genet 2021; 30:149-159. [PMID: 33432327 PMCID: PMC8091037 DOI: 10.1093/hmg/ddaa264] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 10/26/2020] [Accepted: 11/30/2020] [Indexed: 01/02/2023] Open
Abstract
The dystrophin-glycoprotein complex (DGC) is a membrane adhesion complex that provides structural stability at the sarcolemma by linking the myocyte's internal cytoskeleton and external extracellular matrix. In Duchenne muscular dystrophy (DMD), the absence of dystrophin leads to the loss of the DGC at the sarcolemma, resulting in sarcolemmal instability and progressive muscle damage. Utrophin (UTRN), an autosomal homolog of dystrophin, is upregulated in dystrophic muscle and partially compensates for the loss of dystrophin in muscle from patients with DMD. Here, we examine the interaction between Utr and sarcospan (SSPN), a small transmembrane protein that is a core component of both UTRN-glycoprotein complex (UGC) and DGC. We show that additional loss of SSPN causes an earlier onset of disease in dystrophin-deficient mdx mice by reducing the expression of the UGC at the sarcolemma. In order to further evaluate the role of SSPN in maintaining therapeutic levels of Utr at the sarcolemma, we tested the effect of Utr transgenic overexpression in mdx mice lacking SSPN (mdx:SSPN -/-:Utr-Tg). We found that overexpression of Utr restored SSPN to the sarcolemma in mdx muscle but that the ablation of SSPN in mdx muscle reduced Utr at the membrane. Nevertheless, Utr overexpression reduced central nucleation and improved grip strength in both lines. These findings demonstrate that high levels of Utr transgenic overexpression ameliorate the mdx phenotype independently of SSPN expression but that loss of SSPN may impair Utr-based mechanisms that rely on lower levels of Utr protein.
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Affiliation(s)
- Elizabeth M Gibbs
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095, USA
| | - Jackie L McCourt
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095, USA
| | - Kara M Shin
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095, USA
| | - Katherine G Hammond
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095, USA
| | - Jamie L Marshall
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095, USA
| | - Rachelle H Crosbie
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA 90095, USA.,Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA.,Molecular Biology Institute, University of California, Los Angeles, CA, USA
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14
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Chen Q, Xu Z, Chen G, Liu S, Xia Y. Prenatal diagnosis and molecular cytogenetic characterization of three chromosomal abnormalities with favorable outcomes. Taiwan J Obstet Gynecol 2020; 59:338-341. [PMID: 32127162 DOI: 10.1016/j.tjog.2020.01.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2019] [Indexed: 10/24/2022] Open
Abstract
OBJECTIVE Here we present three cases of chromosomal abnormalities with favorable outcomes. CASE REPORT In Case 1, conventional karyotyping revealed a karyotype of 46, XY,t(7; 14) (q35; q13)[4]/46,XY[26]. Array comparative genomic hybridization (aCGH) analysis revealed no genomic imbalance. In Case 2, conventional karyotyping revealed a norma karyotype but aCGH analysis revealed a 3.2M chromosomal duplication (13q12.11q12.12(22, 073, 046_25, 230, 759)x3). In Case 3, aCGH analysis revealed a 5.5M chromosomal deletion (9q21.13q21.32 (78, 645, 382_84, 115, 555) x1). In all three cases, ultrasound examination showed no dysmorphisms and intrauterine growth restrictions (IUGRs) in the fetus. All three pregnancies resulted in phenotypically normal babies. CONCLUSION Chromosomal abnormalities may be associated with favorable outcomes. Combining conventional karyotyping, aCGH analysis and ultrasound results can provide a more accurate risk assessment for pregnant women with advanced age.
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Affiliation(s)
- Qiuqing Chen
- Department of Obstetrics, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China
| | - Zhen Xu
- Department of Gynecology, Hubei Maternal and Child Health Hospital, Wuhan, Hubei, PR China
| | - Guoqiang Chen
- Department of Clinical Laboratory, Huanggang Central Hospital, Huanggang, Hubei, PR China
| | - Sha Liu
- Department of Medical Ultrasonics, Shiyan Maternal and Child Health Hospital, Shiyan, Hubei, PR China
| | - Yanzhi Xia
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China.
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15
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Angelini C. LGMD. Identification, description and classification. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2020; 39:207-217. [PMID: 33458576 PMCID: PMC7783424 DOI: 10.36185/2532-1900-024] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 11/19/2020] [Indexed: 11/05/2022]
Abstract
The term ‘limb girdle muscular dystrophy’ (LGMD) was first used in the seminal paper by Walton and Nattrass in 1954, were they identified LGMD as a separate clinical entity In LGMD description it is pointed out that the category of LGMD most likely comprises a heterogeneous group of disorders. After that the clinical entity was discussed but the LMGD nosography reached a permanent classification during two ENMC workshops held in 1995 and 2017, in the last one an operating definition of LGMD was agreed. This last classification included dystrophies with proximal or distal-proximal presentation with evidence at biopsy of fibre degeneration and splitting, high CK, MRI imaging consistent with degenerative changes, fibro-fatty infiltration present in individuals that reached independent walking ability. To be considered in this group at least two unrelated families should be identified. A review is done of the first genetic characterisation of a number of LGMDs during the late twentieth century and a historical summary is given regarding how these conditions were clinically described and identified, the progresses done from identification of genetic loci, to protein and gene discoveries are reported. The LGMD described on which such historical progresses were done are the recessive calpainopathy (LGMD 2A/R1), dysferlinopathy (LGMD 2B/R2), sarcoglycanopathy (LGMD 2C-2F/R3-R6) types and the dominant type due to TPNO3 variants named transportinopathy (LGMD 1F/D2). Because of new diagnostic techniques such as exome and genome sequencing, it is likely that many other subtypes of LGMD might be identified in the future, however the lesson from the past discoveries can be useful for scientists and clinicians.
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16
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The ties that bind: functional clusters in limb-girdle muscular dystrophy. Skelet Muscle 2020; 10:22. [PMID: 32727611 PMCID: PMC7389686 DOI: 10.1186/s13395-020-00240-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 07/16/2020] [Indexed: 12/13/2022] Open
Abstract
The limb-girdle muscular dystrophies (LGMDs) are a genetically pleiomorphic class of inherited muscle diseases that are known to share phenotypic features. Selected LGMD genetic subtypes have been studied extensively in affected humans and various animal models. In some cases, these investigations have led to human clinical trials of potential disease-modifying therapies, including gene replacement strategies for individual subtypes using adeno-associated virus (AAV) vectors. The cellular localizations of most proteins associated with LGMD have been determined. However, the functions of these proteins are less uniformly characterized, thus limiting our knowledge of potential common disease mechanisms across subtype boundaries. Correspondingly, broad therapeutic strategies that could each target multiple LGMD subtypes remain less developed. We believe that three major "functional clusters" of subcellular activities relevant to LGMD merit further investigation. The best known of these is the glycosylation modifications associated with the dystroglycan complex. The other two, mechanical signaling and mitochondrial dysfunction, have been studied less systematically but are just as promising with respect to the identification of significant mechanistic subgroups of LGMD. A deeper understanding of these disease pathways could yield a new generation of precision therapies that would each be expected to treat a broader range of LGMD patients than a single subtype, thus expanding the scope of the molecular medicines that may be developed for this complex array of muscular dystrophies.
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17
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Demonbreun AR, Wyatt EJ, Fallon KS, Oosterbaan CC, Page PG, Hadhazy M, Quattrocelli M, Barefield DY, McNally EM. A gene-edited mouse model of limb-girdle muscular dystrophy 2C for testing exon skipping. Dis Model Mech 2019; 13:dmm040832. [PMID: 31582396 PMCID: PMC6906631 DOI: 10.1242/dmm.040832] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 09/23/2019] [Indexed: 12/21/2022] Open
Abstract
Limb-girdle muscular dystrophy type 2C is caused by autosomal recessive mutations in the γ-sarcoglycan (SGCG) gene. The most common SGCG mutation is a single nucleotide deletion from a stretch of five thymine residues in SGCG exon 6 (521ΔT). This founder mutation disrupts the transcript reading frame, abolishing protein expression. An antisense oligonucleotide exon-skipping method to reframe the human 521ΔT transcript requires skipping four exons to generate a functional, internally truncated protein. In vivo evaluation of this multi-exon skipping, antisense-mediated therapy requires a genetically appropriate mouse model. The human and mouse γ-sarcoglycan genes are highly homologous in sequence and gene structure, including the exon 6 region harboring the founder mutation. Herein, we describe a new mouse model of this form of limb-girdle muscular dystrophy generated using CRISPR/Cas9-mediated gene editing to introduce a single thymine deletion in murine exon 6, recreating the 521ΔT point mutation in Sgcg These mice express the 521ΔT transcript, lack γ-sarcoglycan protein and exhibit a severe dystrophic phenotype. Phenotypic characterization demonstrated reduced muscle mass, increased sarcolemmal leak and fragility, and decreased muscle function, consistent with the human pathological findings. Furthermore, we showed that intramuscular administration of a murine-specific multiple exon-directed antisense oligonucleotide cocktail effectively corrected the 521ΔT reading frame. These data demonstrate a molecularly and pathologically suitable model for in vivo testing of a multi-exon skipping strategy to advance preclinical development of this genetic correction approach.
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Affiliation(s)
- Alexis R Demonbreun
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
- Department of Pharmacology, Northwestern University, Chicago, IL 60611, USA
| | - Eugene J Wyatt
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Katherine S Fallon
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Claire C Oosterbaan
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Patrick G Page
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Michele Hadhazy
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Mattia Quattrocelli
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
| | - David Y Barefield
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Elizabeth M McNally
- Center for Genetic Medicine, Northwestern University, Chicago, IL 60611, USA
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18
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Vo AH, Swaggart KA, Woo A, Gao QQ, Demonbreun AR, Fallon KS, Quattrocelli M, Hadhazy M, Page PGT, Chen Z, Eskin A, Squire K, Nelson SF, McNally EM. Dusp6 is a genetic modifier of growth through enhanced ERK activity. Hum Mol Genet 2019; 28:279-289. [PMID: 30289454 DOI: 10.1093/hmg/ddy349] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 09/26/2018] [Indexed: 12/21/2022] Open
Abstract
Like other single-gene disorders, muscular dystrophy displays a range of phenotypic heterogeneity even with the same primary mutation. Identifying genetic modifiers capable of altering the course of muscular dystrophy is one approach to deciphering gene-gene interactions that can be exploited for therapy development. To this end, we used an intercross strategy in mice to map modifiers of muscular dystrophy. We interrogated genes of interest in an interval on mouse chromosome 10 associated with body mass in muscular dystrophy as skeletal muscle contributes significantly to total body mass. Using whole-genome sequencing of the two parental mouse strains combined with deep RNA sequencing, we identified the Met62Ile substitution in the dual-specificity phosphatase 6 (Dusp6) gene from the DBA/2 J (D2) mouse strain. DUSP6 is a broadly expressed dual-specificity phosphatase protein, which binds and dephosphorylates extracellular-signal-regulated kinase (ERK), leading to decreased ERK activity. We found that the Met62Ile substitution reduced the interaction between DUSP6 and ERK resulting in increased ERK phosphorylation and ERK activity. In dystrophic muscle, DUSP6 Met62Ile is strongly upregulated to counteract its reduced activity. We found that myoblasts from the D2 background were insensitive to a specific small molecule inhibitor of DUSP6, while myoblasts expressing the canonical DUSP6 displayed enhanced proliferation after exposure to DUSP6 inhibition. These data identify DUSP6 as an important regulator of ERK activity in the setting of muscle growth and muscular dystrophy.
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Affiliation(s)
- Andy H Vo
- Committee on Development, Regeneration and Stem Cell Biology, The University of Chicago, Chicago, IL
| | | | - Anna Woo
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago IL
| | - Quan Q Gao
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago IL
| | - Alexis R Demonbreun
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago IL
| | - Katherine S Fallon
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago IL
| | - Mattia Quattrocelli
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago IL
| | - Michele Hadhazy
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago IL
| | - Patrick G T Page
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago IL
| | - Zugen Chen
- Departments of Human Genetics and Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Ascia Eskin
- Departments of Human Genetics and Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Kevin Squire
- Departments of Human Genetics and Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Stanley F Nelson
- Departments of Human Genetics and Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Elizabeth M McNally
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago IL
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19
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Identification of thiostrepton as a pharmacological approach to rescue misfolded alpha-sarcoglycan mutant proteins from degradation. Sci Rep 2019; 9:6915. [PMID: 31061434 PMCID: PMC6502821 DOI: 10.1038/s41598-019-43399-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 04/18/2019] [Indexed: 12/12/2022] Open
Abstract
Limb-girdle muscular dystrophy type 2D (LGMD2D) is characterized by a progressive proximal muscle weakness. LGMD2D is caused by mutations in the gene encoding α-sarcoglycan (α-SG), a dystrophin-associated glycoprotein that plays a key role in the maintenance of sarcolemma integrity in striated muscles. We report here on the development of a new in vitro high-throughput screening assay that allows the monitoring of the proper localization of the most prevalent mutant form of α-SG (R77C substitution). Using this assay, we screened a library of 2560 FDA-approved drugs and bioactive compounds and identified thiostrepton, a cyclic antibiotic, as a potential drug to repurpose for LGMD2D treatment. Characterization of the thiostrepton effect revealed a positive impact on R77C-α-SG and other missense mutant protein localization (R34H, I124T, V247M) in fibroblasts overexpressing these proteins. Finally, further investigations of the molecular mechanisms of action of the compound revealed an inhibition of the chymotrypsin-like activity of the proteasome 24 h after thiostrepton treatment and a synergistic effect with bortezomib, an FDA-approved proteasome inhibitor. This study reports on the first in vitro model for LGMD2D that is compatible with high-throughput screening and proposes a new therapeutic option for LGMD2D caused by missense mutations of α-SG.
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20
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Younus M, Ahmad F, Malik E, Bilal M, Kausar M, Abbas S, Shaheen S, Kakar MU, Alfadhel M, Umair M. SGCD Homozygous Nonsense Mutation (p.Arg97 ∗) Causing Limb-Girdle Muscular Dystrophy Type 2F (LGMD2F) in a Consanguineous Family, a Case Report. Front Genet 2019; 9:727. [PMID: 30733730 PMCID: PMC6354032 DOI: 10.3389/fgene.2018.00727] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 12/22/2018] [Indexed: 12/14/2022] Open
Abstract
Background: Limb-girdle muscular dystrophy (LGMD) is an increasingly heterogeneous category of inherited muscle diseases, mainly affecting the muscles of shoulder areas and the hip, segregating in both autosomal recessive and dominant manner. To-date, thirty-one loci have been identified for LGMD including seven autosomal dominant (LGMD type 1) and twenty four autosomal recessive (LGMD type 2) inherited loci. Methodology/Laboratory Examination: The present report describes a consanguineous family segregating LGMD2F in an autosomal recessive pattern. The affected individual is an 11-year-old boy having two brothers and a sister. Direct targeted next generation sequencing was performed for the single affected individual (VI-1) followed by Sanger sequencing. Results: Targeted next generation sequencing revealed a novel homozygous nonsense mutation (c.289C>T; p.Arg97∗) in the exon 3 of the delta-sarcoglycan (SGCD) gene, that introduces a premature stop codon (TCA), resulting in a nonsense mediated decay or a truncated protein product. Discussion and Conclusion: This is the first report of LGMD2F caused by an SGCD variant in a Pakistani population. The mutation identified in the present investigation extends the body of evidence implicating the gene SGCD in causing LGMD2F and might help in genetic counseling, which is more important to deliver the risk of carrier or affected in the future pregnancies.
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Affiliation(s)
- Muhammad Younus
- State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, Peking-Tsinghua Center for Life Sciences, PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, China.,Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Farooq Ahmad
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Erum Malik
- Department of Biochemistry, Shah Abdul Latif University Khairpur, Khairpur, Pakistan
| | - Muhammad Bilal
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Mehran Kausar
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan.,DMLS Department, The University of Lahore, Islamabad Campus, Islamabad, Pakistan
| | - Safdar Abbas
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Shabnam Shaheen
- Department of Higher Education, Government Girls Degree College Serai Naurang (Lakki Marwat), Peshawar, Pakistan
| | - Mohib Ullah Kakar
- School of Life Sciences, Beijing Institute of Technology, Beijing, China
| | - Majid Alfadhel
- Division of Genetics, Department of Pediatrics, King Abdulaziz Medical City, Riyadh, Saudi Arabia.,Medical Genomics Research Department, King Abdullah International Medical Research Center (KAIMRC), King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard-Health Affairs (MNGHA), Riyadh, Saudi Arabia
| | - Muhammad Umair
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan.,Medical Genomics Research Department, King Abdullah International Medical Research Center (KAIMRC), King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard-Health Affairs (MNGHA), Riyadh, Saudi Arabia
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21
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Taghizadeh E, Rezaee M, Barreto GE, Sahebkar A. Prevalence, pathological mechanisms, and genetic basis of limb-girdle muscular dystrophies: A review. J Cell Physiol 2018; 234:7874-7884. [PMID: 30536378 DOI: 10.1002/jcp.27907] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 10/23/2018] [Indexed: 12/17/2022]
Abstract
Limb-girdle muscular dystrophies (LGMDs) are a highly heterogeneous group of neuromuscular disorders that are associated with weakness and wasting of muscles in legs and arms. Signs and symptoms may begin at any age and usually worsen by time. LGMDs are autosomal disorders with different types and their prevalence is not the same in different areas. New technologies such as next-generation sequencing can accelerate their diagnosis. Several important pathological mechanisms that are involved in the pathology of the LGMD include abnormalities in dystrophin-glycoprotein complex, the sarcomere, glycosylation of dystroglycan, vesicle and molecular trafficking, signal transduction pathways, and nuclear functions. Here, we provide a comprehensive review that integrates LGMD clinical manifestations, prevalence, and some pathological mechanisms involved in LGMDs.
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Affiliation(s)
- Eskandar Taghizadeh
- Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran.,Department of Medical Genetics, Faculity of Medicine, Mashhad University of Medical Science, Mashhad, Iran
| | - Mehdi Rezaee
- Department of Medical Biotechnology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - George E Barreto
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C, Colombia.,Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
| | - Amirhossein Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Science, Mashhad, Iran.,Neurogenic Inflammation Research Center, Mashhad University of Medical Science, Mashhad, Iran.,School of Pharmacy, Mashhad University of Medical Science, Mashhad, Iran
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22
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De Los Santos S, Palma-Flores C, Zentella-Dehesa A, Canto P, Coral-Vázquez RM. (-)-Epicatechin inhibits development of dilated cardiomyopathy in δ sarcoglycan null mouse. Nutr Metab Cardiovasc Dis 2018; 28:1188-1195. [PMID: 30143409 DOI: 10.1016/j.numecd.2018.06.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 06/18/2018] [Accepted: 06/25/2018] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND AIMS Several studies propose that (-)-epicatechin, a flavonol present in high concentration in the cocoa, has cardioprotective effects. This study aimed to evaluate the impact of (-)-epicatechin on the development of dilated cardiomyopathy in a δ sarcoglycan null mouse model. METHODS AND RESULTS δ Sarcoglycan null mice were treated for 15 days with (-)-epicatechin. Histological and morphometric analysis of the hearts treated mutant mice showed significant reduction of the vasoconstrictions in the coronary arteries as well as fewer areas with fibrosis and a reduction in the loss of the ventricular wall. On the contrary, it was observed a thickening of this region. By Western blot analysis, it was shown, and increment in the phosphorylation level of eNOS and PI3K/AKT/mTOR/p70S6K proteins in the heart of the (-)-epicatechin treated animals. On the other hand, we observed a significantly decreased level of the atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) heart failure markers. CONCLUSION All the results indicate that (-)-epicatechin has the potential to prevent the development of dilated cardiomyopathy of genetic origin and encourages the use of this flavonol as a pharmacological therapy for dilated cardiomyopathy and heart failure diseases.
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MESH Headings
- Animals
- Atrial Natriuretic Factor/metabolism
- Cardiomyopathy, Dilated/enzymology
- Cardiomyopathy, Dilated/genetics
- Cardiomyopathy, Dilated/pathology
- Cardiomyopathy, Dilated/prevention & control
- Catechin/pharmacology
- Coronary Vessels/drug effects
- Coronary Vessels/enzymology
- Coronary Vessels/physiopathology
- Disease Models, Animal
- Fibrosis
- Male
- Mice, Knockout
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/enzymology
- Myocytes, Cardiac/pathology
- Natriuretic Peptide, Brain/metabolism
- Nitric Oxide Synthase Type III/metabolism
- Phosphatidylinositol 3-Kinase/metabolism
- Phosphorylation
- Proto-Oncogene Proteins c-akt/metabolism
- Ribosomal Protein S6 Kinases, 70-kDa/metabolism
- Sarcoglycans/deficiency
- Sarcoglycans/genetics
- Signal Transduction/drug effects
- TOR Serine-Threonine Kinases/metabolism
- Vasoconstriction/drug effects
- Ventricular Function, Left/drug effects
- Ventricular Remodeling/drug effects
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Affiliation(s)
- S De Los Santos
- División de Investigación Biomédica, Centro Médico Nacional 20 de Noviembre, Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, Mexico City, Mexico; Unidad de Investigación en Obesidad, División de Investigación, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico; Clínica de Obesidad, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", Mexico City, Mexico
| | - C Palma-Flores
- División de Investigación Biomédica, Centro Médico Nacional 20 de Noviembre, Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, Mexico City, Mexico; Catedrático CONACYT, Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico City, México
| | - A Zentella-Dehesa
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico; Unidad de Bioquímica, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", Mexico City, Mexico
| | - P Canto
- Unidad de Investigación en Obesidad, División de Investigación, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico; Clínica de Obesidad, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", Mexico City, Mexico
| | - R M Coral-Vázquez
- División de Investigación Biomédica, Centro Médico Nacional 20 de Noviembre, Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, Mexico City, Mexico; Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón s/n, Col. Casco de Santo Tomás, Delegación Miguel Hidalgo, Mexico City, 11340, Mexico.
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23
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Elloumi-Zghal H, Chaabouni Bouhamed H. Genetics and genomic medicine in Tunisia. Mol Genet Genomic Med 2018; 6:134-159. [PMID: 29663716 PMCID: PMC5902400 DOI: 10.1002/mgg3.392] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 03/07/2018] [Indexed: 01/19/2023] Open
Abstract
Genetics and genomic medicine in Tunisia.
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24
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Biobank-driven genomic discovery yields new insight into atrial fibrillation biology. Nat Genet 2018; 50:1234-1239. [PMID: 30061737 DOI: 10.1038/s41588-018-0171-3] [Citation(s) in RCA: 441] [Impact Index Per Article: 73.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 06/01/2018] [Indexed: 02/07/2023]
Abstract
To identify genetic variation underlying atrial fibrillation, the most common cardiac arrhythmia, we performed a genome-wide association study of >1,000,000 people, including 60,620 atrial fibrillation cases and 970,216 controls. We identified 142 independent risk variants at 111 loci and prioritized 151 functional candidate genes likely to be involved in atrial fibrillation. Many of the identified risk variants fall near genes where more deleterious mutations have been reported to cause serious heart defects in humans (GATA4, MYH6, NKX2-5, PITX2, TBX5)1, or near genes important for striated muscle function and integrity (for example, CFL2, MYH7, PKP2, RBM20, SGCG, SSPN). Pathway and functional enrichment analyses also suggested that many of the putative atrial fibrillation genes act via cardiac structural remodeling, potentially in the form of an 'atrial cardiomyopathy'2, either during fetal heart development or as a response to stress in the adult heart.
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Abstract
PURPOSE OF REVIEW To construct a framework to understand the different molecular interventions for muscular dystrophy. RECENT FINDINGS The recent approval of antisense oligonucleotides treatment for Duchenne muscular dystrophy and spinal muscular atrophy and current clinical trials using recombinant adeno-associated virus for the treatment of those diseases suggests that we are at a tipping point where we are able to treat and potentially cure muscular dystrophies. Understanding the basic molecular pathogenesis of muscular dystrophies and the molecular biology of the treatment allows for critical evaluation of the proposed therapies.
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Affiliation(s)
- Ava Y Lin
- Department of Neurology, University of Washington, Box 356465, 1959 NE Pacific Street, Seattle, WA, 98195-6465, USA
| | - Leo H Wang
- Department of Neurology, University of Washington, Box 356465, 1959 NE Pacific Street, Seattle, WA, 98195-6465, USA.
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Wyatt EJ, Demonbreun AR, Kim EY, Puckelwartz MJ, Vo AH, Dellefave-Castillo LM, Gao QQ, Vainzof M, Pavanello RCM, Zatz M, McNally EM. Efficient exon skipping of SGCG mutations mediated by phosphorodiamidate morpholino oligomers. JCI Insight 2018; 3:99357. [PMID: 29720576 DOI: 10.1172/jci.insight.99357] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 04/05/2018] [Indexed: 12/15/2022] Open
Abstract
Exon skipping uses chemically modified antisense oligonucleotides to modulate RNA splicing. Therapeutically, exon skipping can bypass mutations and restore reading frame disruption by generating internally truncated, functional proteins to rescue the loss of native gene expression. Limb-girdle muscular dystrophy type 2C is caused by autosomal recessive mutations in the SGCG gene, which encodes the dystrophin-associated protein γ-sarcoglycan. The most common SGCG mutations disrupt the transcript reading frame abrogating γ-sarcoglycan protein expression. In order to treat most SGCG gene mutations, it is necessary to skip 4 exons in order to restore the SGCG transcript reading frame, creating an internally truncated protein referred to as Mini-Gamma. Using direct reprogramming of human cells with MyoD, myogenic cells were tested with 2 antisense oligonucleotide chemistries, 2'-O-methyl phosphorothioate oligonucleotides and vivo-phosphorodiamidate morpholino oligomers, to induce exon skipping. Treatment with vivo-phosphorodiamidate morpholino oligomers demonstrated efficient skipping of the targeted exons and corrected the mutant reading frame, resulting in the expression of a functional Mini-Gamma protein. Antisense-induced exon skipping of SGCG occurred in normal cells and those with multiple distinct SGCG mutations, including the most common 521ΔT mutation. These findings demonstrate a multiexon-skipping strategy applicable to the majority of limb-girdle muscular dystrophy 2C patients.
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Affiliation(s)
- Eugene J Wyatt
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Alexis R Demonbreun
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Ellis Y Kim
- Committee on Molecular Medicine and Molecular Pathogenesis and
| | - Megan J Puckelwartz
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Andy H Vo
- Committee on Developmental Biology and Regenerative Medicine, The University of Chicago, Chicago, Illinois, USA
| | - Lisa M Dellefave-Castillo
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Quan Q Gao
- Division of Hematology/Oncology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Mariz Vainzof
- Human Genome and Stem-Cell Center, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Rita C M Pavanello
- Human Genome and Stem-Cell Center, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Mayana Zatz
- Human Genome and Stem-Cell Center, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Elizabeth M McNally
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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Humanizing the mdx mouse model of DMD: the long and the short of it. NPJ Regen Med 2018; 3:4. [PMID: 29479480 PMCID: PMC5816599 DOI: 10.1038/s41536-018-0045-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 12/19/2017] [Accepted: 01/04/2018] [Indexed: 12/26/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a common fatal heritable myopathy, with cardiorespiratory failure occurring by the third decade of life. There is no specific treatment for DMD cardiomyopathy, in large part due to a lack of understanding of the mechanisms underlying the cardiac failure. Mdx mice, which have the same dystrophin mutation as human patients, are of limited use, as they do not develop early dilated cardiomyopathy as seen in patients. Here we summarize the usefulness of the various commonly used DMD mouse models, highlight a model with shortened telomeres like humans, and identify directions that warrant further investigation.
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Bulakh MV, Ryzhkova OP, Polyakov AV. Sarcoglycanopathies: Clinical, Molecular and Genetic Characteristics, Epidemiology, Diagnostics and Treatment Options. RUSS J GENET+ 2018. [DOI: 10.1134/s1022795418020059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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McMorran BJ, Miceli MC, Baum LG. Lectin-binding characterizes the healthy human skeletal muscle glycophenotype and identifies disease-specific changes in dystrophic muscle. Glycobiology 2017; 27:1134-1143. [PMID: 28973355 PMCID: PMC6283322 DOI: 10.1093/glycob/cwx073] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 08/08/2017] [Accepted: 08/21/2017] [Indexed: 12/27/2022] Open
Abstract
Our understanding of muscle glycosylation to date has derived from studies in mouse models and a limited number of human lectin histochemistry studies. As various therapeutic approaches aimed at treating patients with muscular dystrophies are being translated from rodent models to human, it is critical to better understand human muscle glycosylation and relevant disease-specific differences between healthy and dystrophic muscle. Here, we report the first quantitative characterization of human muscle glycosylation, and identify differentiation- and disease-specific differences in human muscle glycosylation. Utilizing a panel of 13 lectins with varying glycan specificities, we surveyed lectin binding to primary and immortalized myoblasts and myotubes from healthy and dystrophic sources. Following differentiation of primary and immortalized healthy human muscle cells, we observed increased binding of Narcissus pseudonarcissus agglutinin (NPA), PNA, MAA-II and WFA to myotubes compared to myoblasts. Following differentiation of immortalized healthy and dystrophic human muscle cells, we observed disease-specific differences in binding of NPA, Jac and Tricosanthes japonica agglutinin-I (TJA-I) to differentiated myotubes. We also observed differentiation- and disease-specific differences in binding of NPA, Jac, PNA, TJA-I and WFA to glycoprotein receptors in muscle cells. Additionally, Jac, PNA and WFA precipitated functionally glycosylated α-DG, that bound laminin, while NPA and TJA-I did not. Lectin histochemistry of healthy and dystrophic human muscle sections identified disease-specific differences in binding of O-glycan and sialic acid-specific lectins between healthy and dystrophic muscle. These results indicate that specific and discrete changes in glycosylation occur following differentiation, and identify specific lectins as potential biomarkers sensitive to changes in healthy human muscle glycosylation.
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Affiliation(s)
- Brian J McMorran
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Ave., CHS 14-127, Los Angeles, CA 90095, USA
| | - M Carrie Miceli
- Department of Microbiology, Immunology and Molecular Genetics, University of California Los Angeles, 609 Charles E Young Dr E, Los Angeles, CA 90095, USA
| | - Linda G Baum
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Ave., CHS 14-127, Los Angeles, CA 90095, USA
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McElhanon KE, Bhattacharya S. Altered membrane integrity in the progression of muscle diseases. Life Sci 2017; 192:166-172. [PMID: 29183798 DOI: 10.1016/j.lfs.2017.11.035] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 11/12/2017] [Accepted: 11/22/2017] [Indexed: 12/27/2022]
Abstract
Sarcolemmal integrity is orchestrated through the interplay of preserving membrane strength and fast tracking the membrane repair process during an event of compromised membrane fragility. Several molecular players have been identified that act in a concerted fashion to maintain the barrier function of the muscle membrane. Substantial research findings in the field of muscle biology point out the importance of maintaining membrane integrity as a key contributory factor to cellular homeostasis. Innumerable data on the progression of membrane pathology associated with compromised muscle membrane integrity support targeting sarcolemmal integrity in skeletal and cardiac muscle as a model therapeutic strategy to alleviate some of the pathologic conditions. This review will discuss strategies that researchers have undertaken to compensate for an imbalance in sarcolemma membrane fragility and membrane repair to maintain muscle membrane integrity.
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Affiliation(s)
- Kevin E McElhanon
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, 473 W. 12th Ave, Columbus, OH 43210-1252, United States
| | - Sayak Bhattacharya
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, 473 W. 12th Ave, Columbus, OH 43210-1252, United States.
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Quattrocelli M, Salamone IM, Page PG, Warner JL, Demonbreun AR, McNally EM. Intermittent Glucocorticoid Dosing Improves Muscle Repair and Function in Mice with Limb-Girdle Muscular Dystrophy. THE AMERICAN JOURNAL OF PATHOLOGY 2017; 187:2520-2535. [PMID: 28823869 DOI: 10.1016/j.ajpath.2017.07.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 07/03/2017] [Accepted: 07/13/2017] [Indexed: 12/17/2022]
Abstract
The muscular dystrophies are genetically diverse. Shared pathological features among muscular dystrophies include breakdown, or loss of muscle, and accompanying fibrotic replacement. Novel strategies are needed to enhance muscle repair and function and to slow this pathological remodeling. Glucocorticoid steroids, like prednisone, are known to delay loss of ambulation in patients with Duchenne muscular dystrophy but are accompanied by prominent adverse effects. However, less is known about the effects of steroid administration in other types of muscular dystrophies, including limb-girdle muscular dystrophies (LGMDs). LGMD 2B is caused by loss of dysferlin, a membrane repair protein, and LGMD 2C is caused by loss of the dystrophin-associated protein, γ-sarcoglycan. Herein, we assessed the efficacy of steroid dosing on sarcolemmal repair, muscle function, histopathology, and the regenerative capacity of primary muscle cells. We found that in murine models of LGMD 2B and 2C, daily prednisone dosing reduced muscle damage and fibroinflammatory infiltration. However, daily prednisone dosing also correlated with increased muscle adipogenesis and atrophic remodeling. Conversely, intermittent dosing of prednisone, provided once weekly, enhanced muscle repair and did not induce atrophy or adipogenesis, and was associated with improved muscle function. These data indicate that dosing frequency of glucocorticoid steroids affects muscle remodeling in non-Duchenne muscular dystrophies, suggesting a positive outcome associated with intermittent steroid dosing in LGMD 2B and 2C muscle.
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Affiliation(s)
- Mattia Quattrocelli
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Isabella M Salamone
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Patrick G Page
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - James L Warner
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Alexis R Demonbreun
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Elizabeth M McNally
- Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois.
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Alavi A, Esmaeili S, Nilipour Y, Nafissi S, Tonekaboni SH, Zamani G, Ashrafi MR, Kahrizi K, Najmabadi H, Jazayeri F. LGMD2E is the most common type of sarcoglycanopathies in the Iranian population. J Neurogenet 2017; 31:161-169. [DOI: 10.1080/01677063.2017.1346093] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Afagh Alavi
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Sara Esmaeili
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Yalda Nilipour
- Pediatric Pathology Research Center, Mofid Children Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Shahriar Nafissi
- Department of Neurology, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Hasan Tonekaboni
- Pediatric Neurology Center of Excellence, Department of Pediatric Neurology, Mofid Children Hospital, Faculty of Medicine, Shahid Beheshti Medical university, Tehran, Iran
| | - Gholamreza Zamani
- Children's Medical Center, Tehran University of Medical Sciences, Iranian Epilepsy Association Board, Tehran, Iran
| | - Mahmoud Reza Ashrafi
- Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Kimia Kahrizi
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Hossein Najmabadi
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Fatemeh Jazayeri
- Department of Neurology, Tehran University of Medical Sciences, Tehran, Iran
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Marsolier J, Laforet P, Pegoraro E, Vissing J, Richard I. 1st International Workshop on Clinical trial readiness for sarcoglycanopathies 15-16 November 2016, Evry, France. Neuromuscul Disord 2017; 27:683-692. [PMID: 28521973 DOI: 10.1016/j.nmd.2017.02.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 02/14/2017] [Indexed: 11/25/2022]
Affiliation(s)
- Justine Marsolier
- Généthon, INSERM, U951, INTEGRARE Research Unit, Evry F-91002, France
| | | | | | - John Vissing
- Copenhagen Neuromuscular Center, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Isabelle Richard
- Généthon, INSERM, U951, INTEGRARE Research Unit, Evry F-91002, France.
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Khadilkar SV, Faldu HD, Patil SB, Singh R. Limb-girdle Muscular Dystrophies in India: A Review. Ann Indian Acad Neurol 2017; 20:87-95. [PMID: 28615891 PMCID: PMC5470147 DOI: 10.4103/aian.aian_81_17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Limb-girdle muscular dystrophies (LGMDs) are common in India. Information on LGMDs has been gradually evolving in the recent years. This information is scattered in case series and case studies. The aim of this study is to collate available Indian information on LGMDs and put it in perspective. PubMed search using keywords such as limb-girdle muscular dystrophies in India, sarcoglycanopathies, dysferlinopathy, calpainopathy, and GNE myopathy was carried out. The published information on LGMDs in Indian context suggests that dysferlinopathy, calpainopathy, sarcoglycanopathies, and other myopathies such as GNE myopathy are frequently seen in India. Besides these, anecdotal reports of many other forms are available, some with genetic support and others showing immunocytochemical defects. The genotypic information on LGMDs is gradually evolving and founder mutations have been detected in selected populations. Further multicenter studies are necessary to document the incidence and prevalence of these common conditions in India.
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Affiliation(s)
| | - Hinaben Dayalal Faldu
- Department of Neurology, Grant Government Medical College and J. J. Hospital, Mumbai, Maharashtra, India
| | - Sarika Bapuso Patil
- Department of Neurology, Grant Government Medical College and J. J. Hospital, Mumbai, Maharashtra, India
| | - Rakesh Singh
- Department of Neurology, Grant Government Medical College and J. J. Hospital, Mumbai, Maharashtra, India
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Reddy HM, Hamed SA, Lek M, Mitsuhashi S, Estrella E, Jones MD, Mahoney LJ, Duncan AR, Cho KA, Macarthur DG, Kunkel LM, Kang PB. Homozygous nonsense mutation in SGCA is a common cause of limb-girdle muscular dystrophy in Assiut, Egypt. Muscle Nerve 2016; 54:690-5. [PMID: 26934379 DOI: 10.1002/mus.25094] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Revised: 02/22/2016] [Accepted: 02/26/2016] [Indexed: 01/18/2023]
Abstract
INTRODUCTION The genetic causes of limb-girdle muscular dystrophy (LGMD) have been studied in numerous countries, but such investigations have been limited in Egypt. METHODS A cohort of 30 families with suspected LGMD from Assiut, Egypt, was studied using immunohistochemistry, homozygosity mapping, Sanger sequencing, and whole exome sequencing. RESULTS Six families were confirmed to have pathogenic mutations, 4 in SGCA and 2 in DMD. Of these, 3 families harbored a single nonsense mutation in SGCA, suggesting that this may be a common mutation in Assiut, Egypt, originating from a founder effect. CONCLUSIONS The Assiut region in Egypt appears to share at least several of the common LGMD genes found in other parts of the world. It is notable that 4 of the 6 mutations were ascertained by means of whole exome sequencing, even though it was the last approach adopted. This illustrates the power of this technique for identifying causative mutations for muscular dystrophies. Muscle Nerve 54: 690-695, 2016.
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Affiliation(s)
- Hemakumar M Reddy
- Division of Pediatric Neurology, University of Florida College of Medicine, PO Box 100296, Gainesville, Florida, USA, 32610
| | - Sherifa A Hamed
- Department of Neurology and Psychiatry, Assiut University Hospital, Assiut, Egypt
| | - Monkol Lek
- Analytic and Translational Genetics Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute of the Massachusetts Institute of Technology and Harvard University, Cambridge, Massachusetts, USA
| | - Satomi Mitsuhashi
- Division of Genetics & Genomics, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Elicia Estrella
- Division of Genetics & Genomics, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Michael D Jones
- Division of Pediatric Neurology, University of Florida College of Medicine, PO Box 100296, Gainesville, Florida, USA, 32610
| | - Lane J Mahoney
- Division of Genetics & Genomics, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Anna R Duncan
- Division of Genetics & Genomics, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Kyung-Ah Cho
- Division of Pediatric Neurology, University of Florida College of Medicine, PO Box 100296, Gainesville, Florida, USA, 32610
| | - Daniel G Macarthur
- Analytic and Translational Genetics Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA.,Broad Institute of the Massachusetts Institute of Technology and Harvard University, Cambridge, Massachusetts, USA
| | - Louis M Kunkel
- Division of Genetics & Genomics, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Peter B Kang
- Division of Pediatric Neurology, University of Florida College of Medicine, PO Box 100296, Gainesville, Florida, USA, 32610. .,Department of Neurology and Department of Molecular Genetics and Microbiology, University of Florida College of Medicine, Gainesville, Florida, USA.
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Cutroneo G, Vermiglio G, Centofanti A, Rizzo G, Runci M, Favaloro A, Piancino MG, Bracco P, Ramieri G, Bianchi F, Speciale F, Arco A, Trimarchi F. Morphofunctional compensation of masseter muscles in unilateral posterior crossbite patients. Eur J Histochem 2016; 60:2605. [PMID: 27349311 PMCID: PMC4933822 DOI: 10.4081/ejh.2016.2605] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 03/11/2016] [Accepted: 03/13/2016] [Indexed: 11/23/2022] Open
Abstract
Unilateral posterior crossbite is a widespread, asymmetric malocclusion characterized by an inverse relationship of the upper and lower buccal dental cusps, in the molar and premolar regions, on one side only of the dental arch. Patients with unilateral posterior crossbite exhibit an altered chewing cycles and the crossbite side masseter results to be less active with respect to the contralateral one. Few studies about morphological features of masticatory muscle in malocclusion disorders exist and most of these have been performed on animal models. The aim of the present study was to evaluate morphological and protein expression characteristics of masseter muscles in patients affected by unilateral posterior crossbite, by histological and immunofluorescence techniques. We have used antibody against PAX-7, marker of satellite cells, and against α-, β-, γ-, δ-, ε- and ζ-sarcoglycans which are transmembrane glycoproteins involved in sarcolemma stabilization. By statistical analysis we have evaluated differences in amount of myonucley between contralateral and ipsilateral side. Results have shown: i) altered fibers morphology and atrophy of ipsilateral muscle if compared to the contralateral one; ii) higher number of myonuclei and PAX-7 positive cells in contralateral side than ipsilateral one; iii) higher pattern of fluorescence for all tested sarcoglycans in contralateral side than ipsilateral one. Results show that in unilateral posterior crossbite hypertrophic response of contralateral masseter and atrophic events in ipsilateral masseter take place; by that, in unilateral posterior crossbite malocclusion masticatory muscles modify their morphology depending on the function. That could be relevant in understanding and healing of malocclusion disorders; in fact, the altered balance about structure and function between ipsilateral and contralateral muscles could, long-term, lead and/ or worsen skeletal asymmetries.
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Massalska D, Zimowski JG, Bijok J, Kucińska-Chahwan A, Łusakowska A, Jakiel G, Roszkowski T. Prenatal diagnosis of congenital myopathies and muscular dystrophies. Clin Genet 2016; 90:199-210. [PMID: 27197572 DOI: 10.1111/cge.12801] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/05/2016] [Accepted: 05/08/2016] [Indexed: 12/14/2022]
Abstract
Congenital myopathies and muscular dystrophies constitute a genetically and phenotypically heterogeneous group of rare inherited diseases characterized by muscle weakness and atrophy, motor delay and respiratory insufficiency. To date, curative care is not available for these diseases, which may severely affect both life-span and quality of life. We discuss prenatal diagnosis and genetic counseling for families at risk, as well as diagnostic possibilities in sporadic cases.
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Affiliation(s)
- D Massalska
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - J G Zimowski
- Department of Genetics, Institute of Psychiatry and Neurology, Warsaw, Poland
| | - J Bijok
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - A Kucińska-Chahwan
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - A Łusakowska
- Department of Neurology, Medical University of Warsaw, Poland
| | - G Jakiel
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - T Roszkowski
- Department of Obstetrics and Gynecology, Centre of Postgraduate Medical Education, Warsaw, Poland
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Campbell MD, Witcher M, Gopal A, Michele DE. Dilated cardiomyopathy mutations in δ-sarcoglycan exert a dominant-negative effect on cardiac myocyte mechanical stability. Am J Physiol Heart Circ Physiol 2016; 310:H1140-50. [PMID: 26968544 PMCID: PMC4867387 DOI: 10.1152/ajpheart.00521.2015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 03/07/2016] [Indexed: 01/25/2023]
Abstract
Delta-sarcoglycan is a component of the sarcoglycan subcomplex within the dystrophin-glycoprotein complex located at the plasma membrane of muscle cells. While recessive mutations in δ-sarcoglycan cause limb girdle muscular dystrophy 2F, dominant mutations in δ-sarcoglycan have been linked to inherited dilated cardiomyopathy (DCM). The purpose of this study was to investigate functional cellular defects present in adult cardiac myocytes expressing mutant δ-sarcoglycans harboring the dominant inherited DCM mutations R71T or R97Q. This study demonstrates that DCM mutant δ-sarcoglycans can be stably expressed in adult rat cardiac myocytes and traffic similarly to wild-type δ-sarcoglycan to the plasma membrane, without perturbing assembly of the dystrophin-glycoprotein complex. However, expression of DCM mutant δ-sarcoglycan in adult rat cardiac myocytes is sufficient to alter cardiac myocyte plasma membrane stability in the presence of mechanical strain. Upon cyclical cell stretching, cardiac myocytes expressing mutant δ-sarcoglycan R97Q or R71T have increased cell-impermeant dye uptake and undergo contractures at greater frequencies than myocytes expressing normal δ-sarcoglycan. Additionally, the R71T mutation creates an ectopic N-linked glycosylation site that results in aberrant glycosylation of the extracellular domain of δ-sarcoglycan. Therefore, appropriate glycosylation of δ-sarcoglycan may also be necessary for proper δ-sarcoglycan function and overall dystrophin-glycoprotein complex function. These studies demonstrate that DCM mutations in δ-sarcoglycan can exert a dominant negative effect on dystrophin-glycoprotein complex function leading to myocardial mechanical instability that may underlie the pathogenesis of δ-sarcoglycan-associated DCM.
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Affiliation(s)
- Matthew D Campbell
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan; and
| | - Marc Witcher
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan; and
| | - Anoop Gopal
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan; and
| | - Daniel E Michele
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan; and Department of Internal Medicine, Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan
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Fayssoil A, Ogna A, Chaffaut C, Chevret S, Guimarães-Costa R, Leturcq F, Wahbi K, Prigent H, Lofaso F, Nardi O, Clair B, Behin A, Stojkovic T, Laforet P, Orlikowski D, Annane D. Natural History of Cardiac and Respiratory Involvement, Prognosis and Predictive Factors for Long-Term Survival in Adult Patients with Limb Girdle Muscular Dystrophies Type 2C and 2D. PLoS One 2016; 11:e0153095. [PMID: 27120200 PMCID: PMC4847860 DOI: 10.1371/journal.pone.0153095] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/23/2016] [Indexed: 12/11/2022] Open
Abstract
Background Type 2C and 2D limb girdle muscular dystrophies (LGMD) are a group of autosomal recessive limb girdle muscular dystrophies manifested by proximal myopathy, impaired respiratory muscle function and cardiomyopathy. The correlation and the prognostic impact of respiratory and heart impairment are poorly described. We aimed to describe the long-term cardiac and respiratory follow-up of these patients and to determine predictive factors of cardio-respiratory events and mortality in LGMD 2C and 2D. Methods We reviewed the charts of 34 LGMD patients, followed from 2005 to 2015, to obtain echocardiographic, respiratory function and sleep recording data. We considered respiratory events (acute respiratory failure, pulmonary sepsis, atelectasis or pneumothorax), cardiac events (acute heart failure, significant cardiac arrhythmia or conduction block, ischemic stroke) and mortality as outcomes of interest for the present analysis. Results A total of 21 patients had type 2C LGMD and 13 patients had type 2D. Median age was 30 years [IQR 24–38]. At baseline, median pulmonary vital capacity (VC) was 31% of predicted value [20–40]. Median maximal inspiratory pressure (MIP) was 31 cmH2O [IQR 20.25–39.75]. Median maximal expiratory pressure (MEP) was 30 cm H2O [20–36]. Median left ventricular ejection fraction (LVEF) was 55% [45–64] with 38% of patients with LVEF <50%. Over a median follow-up of 6 years, we observed 38% respiratory events, 14% cardiac events and 20% mortality. Among baseline characteristics, LVEF and left ventricular end diastolic diameter (LVEDD) were associated with mortality, whilst respiratory parameters (VC, MIP, MEP) and the need for home mechanical ventilation (HMV) were associated with respiratory events. Conclusion In our cohort of severely respiratory impaired type 2C and 2D LGMD, respiratory morbidity was high. Cardiac dysfunction was frequent in particular in LGMD 2C and had an impact on long-term mortality. Trial Registration ClinicalTrials.gov NCT02501083
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Affiliation(s)
- Abdallah Fayssoil
- Service de Réanimation médicale et unité de ventilation à domicile, centre de référence neuromusculaire GNHM, CHU Raymond Poincaré, APHP, Université de Versailles Saint Quentin en Yvelines, Garches, France
- Centre d’Investigation clinique et Innovation technologique CIC 14.29, INSERM, Garches, France
- Institut de Myologie, CHU Pitié Salpetrière, Centre de référence neuro musculaire Paris Est, Université Pierre et Marie Curie Paris VI, Paris, France
- * E-mail:
| | - Adam Ogna
- Service de Réanimation médicale et unité de ventilation à domicile, centre de référence neuromusculaire GNHM, CHU Raymond Poincaré, APHP, Université de Versailles Saint Quentin en Yvelines, Garches, France
- Centre d’Investigation clinique et Innovation technologique CIC 14.29, INSERM, Garches, France
| | - Cendrine Chaffaut
- SBIM, CHU Saint Louis, APHP, Université Paris Diderot, Paris, France
| | - Sylvie Chevret
- SBIM, CHU Saint Louis, APHP, Université Paris Diderot, Paris, France
| | - Raquel Guimarães-Costa
- Institut de Myologie, CHU Pitié Salpetrière, Centre de référence neuro musculaire Paris Est, Université Pierre et Marie Curie Paris VI, Paris, France
| | - France Leturcq
- Laboratoire de biochimie et génétique moléculaire, hôpital Cochin, AP-HP, université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Karim Wahbi
- Service de cardiologie, Hôpital Cochin, APHP, Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Helene Prigent
- Service de Physiologie - Exploration fonctionnelles, CHU Raymond Poincaré, APHP, Université de Versailles saint Quentin en Yvelines, Garches, France
| | - Frederic Lofaso
- Service de Physiologie - Exploration fonctionnelles, CHU Raymond Poincaré, APHP, Université de Versailles saint Quentin en Yvelines, Garches, France
| | - Olivier Nardi
- Service de Réanimation médicale et unité de ventilation à domicile, centre de référence neuromusculaire GNHM, CHU Raymond Poincaré, APHP, Université de Versailles Saint Quentin en Yvelines, Garches, France
| | - Bernard Clair
- Service de Réanimation médicale et unité de ventilation à domicile, centre de référence neuromusculaire GNHM, CHU Raymond Poincaré, APHP, Université de Versailles Saint Quentin en Yvelines, Garches, France
| | - Anthony Behin
- Institut de Myologie, CHU Pitié Salpetrière, Centre de référence neuro musculaire Paris Est, Université Pierre et Marie Curie Paris VI, Paris, France
| | - Tanya Stojkovic
- Institut de Myologie, CHU Pitié Salpetrière, Centre de référence neuro musculaire Paris Est, Université Pierre et Marie Curie Paris VI, Paris, France
| | - Pascal Laforet
- Institut de Myologie, CHU Pitié Salpetrière, Centre de référence neuro musculaire Paris Est, Université Pierre et Marie Curie Paris VI, Paris, France
| | - David Orlikowski
- Service de Réanimation médicale et unité de ventilation à domicile, centre de référence neuromusculaire GNHM, CHU Raymond Poincaré, APHP, Université de Versailles Saint Quentin en Yvelines, Garches, France
- Centre d’Investigation clinique et Innovation technologique CIC 14.29, INSERM, Garches, France
| | - Djillali Annane
- Service de Réanimation médicale et unité de ventilation à domicile, centre de référence neuromusculaire GNHM, CHU Raymond Poincaré, APHP, Université de Versailles Saint Quentin en Yvelines, Garches, France
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Thompson R, Straub V. Limb-girdle muscular dystrophies - international collaborations for translational research. Nat Rev Neurol 2016; 12:294-309. [PMID: 27033376 DOI: 10.1038/nrneurol.2016.35] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The limb-girdle muscular dystrophies (LGMDs) are a diverse group of genetic neuromuscular conditions that usually manifest in the proximal muscles of the hip and shoulder girdles. Since the identification of the first gene associated with the phenotype in 1994, an extensive body of research has identified the genetic defects responsible for over 30 LGMD subtypes, revealed an increasingly varied phenotypic spectrum, and exposed the need to move towards a systems-based understanding of the molecular pathways affected. New sequencing technologies, including whole-exome and whole-genome sequencing, are continuing to expand the range of genes and phenotypes associated with the LGMDs, and new computational approaches are helping clinicians to adapt to this new genomic medicine paradigm. However, 60 years on from the first description of LGMD, no curative therapies exist, and systematic exploration of the natural history is still lacking. To enable rapid translation of basic research to the clinic, well-phenotyped and genetically characterized patient cohorts are a necessity, and appropriate outcome measures and biomarkers must be developed through natural history studies. Here, we review the international collaborations that are addressing these translational research issues, and the lessons learned from large-scale LGMD sequencing programmes.
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Affiliation(s)
- Rachel Thompson
- The John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle upon Tyne NE1 3BZ, UK
| | - Volker Straub
- The John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, International Centre for Life, Central Parkway, Newcastle upon Tyne NE1 3BZ, UK
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43
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Zlotina A, Nikulina T, Yany N, Moiseeva O, Pervunina T, Grekhov E, Kostareva A. Ring chromosome 18 in combination with 18q12.1 (DTNA) interstitial microdeletion in a patient with multiple congenital defects. Mol Cytogenet 2016; 9:18. [PMID: 26893613 PMCID: PMC4758088 DOI: 10.1186/s13039-016-0229-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 02/10/2016] [Indexed: 11/20/2022] Open
Abstract
Background Ring chromosome 18 [r(18)] syndrome represents a relatively rare condition with a complex clinical picture including multiple congenital dysmorphia and varying degrees of mental retardation. The condition is cytogenetically characterized by a complete or mosaic form of ring chromosome 18, with ring formation being usually accompanied by the partial loss of both chromosomal arms. Here we observed a 20-year-old male patient who along with the features typical for r(18) carriers additionally manifested a severe congenital subaortic stenosis. To define the genetic basis of such a compound phenotype, standard cytogenetic and high-resolution molecular-cytogenetic analysis of the patient was performed. Case presentation Standard chromosome analysis of cultured lymphocytes confirmed 46, XY, r(18) karyotype. Array-based comparative genomic hybridization (array-CGH) allowed to define precisely the breakpoints of 18p and 18q terminal deletions, thus identifying the hemizygosity extent, and to reveal an additional duplication adjoining the breakpoint of the 18p deletion. Apart from the terminal imbalances, we found an interstitial microdeletion of 442 kb in size (18q12.1) that encompassed DTNA gene encoding α-dystrobrevin, a member of dystrophin-associated glycoprotein complex. While limited data on the role of DTNA missense mutations in pathogenesis of human cardiac abnormalities exist, a microdeletion corresponding to whole DTNA sequence and not involving other genes has not been earlier described. Conclusions A detailed molecular-cytogenetic characterization of the patient with multiple congenital abnormalities enabled to unravel a combination of genetic defects, namely, a ring chromosome 18 with terminal imbalances and DTNA whole-gene deletion. We suggest that such combination could contribute to the complex phenotype. The findings obtained allow to extend the knowledge of the role of DTNA haploinsufficiency in congenital heart malformation, though further comprehensive functional studies are required. Electronic supplementary material The online version of this article (doi:10.1186/s13039-016-0229-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anna Zlotina
- Almazov Federal Medical Research Centre, Saint-Petersburg, 197341 Russia ; Institute of translational Medicine, ITMO University, Saint-Petersburg, 199034 Russia ; Cytology and Histology Department, Saint Petersburg State University, Saint-Petersburg, 199034 Russia
| | - Tatiana Nikulina
- Almazov Federal Medical Research Centre, Saint-Petersburg, 197341 Russia
| | - Natalia Yany
- Almazov Federal Medical Research Centre, Saint-Petersburg, 197341 Russia
| | - Olga Moiseeva
- Almazov Federal Medical Research Centre, Saint-Petersburg, 197341 Russia
| | - Tatiana Pervunina
- Almazov Federal Medical Research Centre, Saint-Petersburg, 197341 Russia
| | - Eugeny Grekhov
- Almazov Federal Medical Research Centre, Saint-Petersburg, 197341 Russia
| | - Anna Kostareva
- Almazov Federal Medical Research Centre, Saint-Petersburg, 197341 Russia ; Department of Women's and Children's Health, Center for Molecular Medicine, Karolinska Institute, Stockholm, 17176 Sweden
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de Greef JC, Hamlyn R, Jensen BS, O'Campo Landa R, Levy JR, Kobuke K, Campbell KP. Collagen VI deficiency reduces muscle pathology, but does not improve muscle function, in the γ-sarcoglycan-null mouse. Hum Mol Genet 2016; 25:1357-69. [PMID: 26908621 PMCID: PMC4787905 DOI: 10.1093/hmg/ddw018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 01/18/2016] [Indexed: 01/19/2023] Open
Abstract
Muscular dystrophy is characterized by progressive skeletal muscle weakness and dystrophic muscle exhibits degeneration and regeneration of muscle cells, inflammation and fibrosis. Skeletal muscle fibrosis is an excessive deposition of components of the extracellular matrix including an accumulation of Collagen VI. We hypothesized that a reduction of Collagen VI in a muscular dystrophy model that presents with fibrosis would result in reduced muscle pathology and improved muscle function. To test this hypothesis, we crossed γ-sarcoglycan-null mice, a model of limb-girdle muscular dystrophy type 2C, with a Col6a2-deficient mouse model. We found that the resulting γ-sarcoglycan-null/Col6a2Δex5 mice indeed exhibit reduced muscle pathology compared with γ-sarcoglycan-null mice. Specifically, fewer muscle fibers are degenerating, fiber size varies less, Evans blue dye uptake is reduced and serum creatine kinase levels are lower. Surprisingly, in spite of this reduction in muscle pathology, muscle function is not significantly improved. In fact, grip strength and maximum isometric tetanic force are even lower in γ-sarcoglycan-null/Col6a2Δex5 mice than in γ-sarcoglycan-null mice. In conclusion, our results reveal that Collagen VI-mediated fibrosis contributes to skeletal muscle pathology in γ-sarcoglycan-null mice. Importantly, however, our data also demonstrate that a reduction in skeletal muscle pathology does not necessarily lead to an improvement of skeletal muscle function, and this should be considered in future translational studies.
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Affiliation(s)
- Jessica C de Greef
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology and Department of Internal Medicine, The University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA
| | - Rebecca Hamlyn
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology and Department of Internal Medicine, The University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA
| | - Braden S Jensen
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology and Department of Internal Medicine, The University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA
| | - Raul O'Campo Landa
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology and Department of Internal Medicine, The University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA
| | - Jennifer R Levy
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology and Department of Internal Medicine, The University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA
| | - Kazuhiro Kobuke
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology and Department of Internal Medicine, The University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA
| | - Kevin P Campbell
- Howard Hughes Medical Institute, Department of Molecular Physiology and Biophysics, Department of Neurology and Department of Internal Medicine, The University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242, USA
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Parvatiyar MS, Marshall JL, Nguyen RT, Jordan MC, Richardson VA, Roos KP, Crosbie-Watson RH. Sarcospan Regulates Cardiac Isoproterenol Response and Prevents Duchenne Muscular Dystrophy-Associated Cardiomyopathy. J Am Heart Assoc 2015; 4:JAHA.115.002481. [PMID: 26702077 PMCID: PMC4845268 DOI: 10.1161/jaha.115.002481] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Background Duchenne muscular dystrophy is a fatal cardiac and skeletal muscle disease resulting from mutations in the dystrophin gene. We have previously demonstrated that a dystrophin‐associated protein, sarcospan (SSPN), ameliorated Duchenne muscular dystrophy skeletal muscle degeneration by activating compensatory pathways that regulate muscle cell adhesion (laminin‐binding) to the extracellular matrix. Conversely, loss of SSPN destabilized skeletal muscle adhesion, hampered muscle regeneration, and reduced force properties. Given the importance of SSPN to skeletal muscle, we investigated the consequences of SSPN ablation in cardiac muscle and determined whether overexpression of SSPN into mdx mice ameliorates cardiac disease symptoms associated with Duchenne muscular dystrophy cardiomyopathy. Methods and Results SSPN‐null mice exhibited cardiac enlargement, exacerbated cardiomyocyte hypertrophy, and increased fibrosis in response to β‐adrenergic challenge (isoproterenol; 0.8 mg/day per 2 weeks). Biochemical analysis of SSPN‐null cardiac muscle revealed reduced sarcolemma localization of many proteins with a known role in cardiomyopathy pathogenesis: dystrophin, the sarcoglycans (α‐, δ‐, and γ‐subunits), and β1D integrin. Transgenic overexpression of SSPN in Duchenne muscular dystrophy mice (mdxTG) improved cardiomyofiber cell adhesion, sarcolemma integrity, cardiac functional parameters, as well as increased expression of compensatory transmembrane proteins that mediate attachment to the extracellular matrix. Conclusions SSPN regulates sarcolemmal expression of laminin‐binding complexes that are critical to cardiac muscle function and protects against transient and chronic injury, including inherited cardiomyopathy.
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Affiliation(s)
- Michelle S Parvatiyar
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA (M.S.P., J.L.M., R.T.N., V.A.R., R.H.C.W.) Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, CA (M.S.P., J.L.M., M.C.J., V.A.R., K.P.R., R.H.C.W.)
| | - Jamie L Marshall
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA (M.S.P., J.L.M., R.T.N., V.A.R., R.H.C.W.) Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, CA (M.S.P., J.L.M., M.C.J., V.A.R., K.P.R., R.H.C.W.)
| | - Reginald T Nguyen
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA (M.S.P., J.L.M., R.T.N., V.A.R., R.H.C.W.)
| | - Maria C Jordan
- Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, CA (M.S.P., J.L.M., M.C.J., V.A.R., K.P.R., R.H.C.W.) Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA (M.C.J., K.P.R.)
| | - Vanitra A Richardson
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA (M.S.P., J.L.M., R.T.N., V.A.R., R.H.C.W.) Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, CA (M.S.P., J.L.M., M.C.J., V.A.R., K.P.R., R.H.C.W.)
| | - Kenneth P Roos
- Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, CA (M.S.P., J.L.M., M.C.J., V.A.R., K.P.R., R.H.C.W.) Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA (M.C.J., K.P.R.)
| | - Rachelle H Crosbie-Watson
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA (M.S.P., J.L.M., R.T.N., V.A.R., R.H.C.W.) Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, CA (M.S.P., J.L.M., M.C.J., V.A.R., K.P.R., R.H.C.W.) Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA (R.H.C.W.)
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46
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Gao QQ, Wyatt E, Goldstein JA, LoPresti P, Castillo LM, Gazda A, Petrossian N, Earley JU, Hadhazy M, Barefield DY, Demonbreun AR, Bönnemann C, Wolf M, McNally EM. Reengineering a transmembrane protein to treat muscular dystrophy using exon skipping. J Clin Invest 2015; 125:4186-95. [PMID: 26457733 DOI: 10.1172/jci82768] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 09/03/2015] [Indexed: 01/16/2023] Open
Abstract
Exon skipping uses antisense oligonucleotides as a treatment for genetic diseases. The antisense oligonucleotides used for exon skipping are designed to bypass premature stop codons in the target RNA and restore reading frame disruption. Exon skipping is currently being tested in humans with dystrophin gene mutations who have Duchenne muscular dystrophy. For Duchenne muscular dystrophy, the rationale for exon skipping derived from observations in patients with naturally occurring dystrophin gene mutations that generated internally deleted but partially functional dystrophin proteins. We have now expanded the potential for exon skipping by testing whether an internal, in-frame truncation of a transmembrane protein γ-sarcoglycan is functional. We generated an internally truncated γ-sarcoglycan protein that we have termed Mini-Gamma by deleting a large portion of the extracellular domain. Mini-Gamma provided functional and pathological benefits to correct the loss of γ-sarcoglycan in a Drosophila model, in heterologous cell expression studies, and in transgenic mice lacking γ-sarcoglycan. We generated a cellular model of human muscle disease and showed that multiple exon skipping could be induced in RNA that encodes a mutant human γ-sarcoglycan. Since Mini-Gamma represents removal of 4 of the 7 coding exons in γ-sarcoglycan, this approach provides a viable strategy to treat the majority of patients with γ-sarcoglycan gene mutations.
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MESH Headings
- Animals
- Codon, Nonsense/genetics
- Diaphragm/metabolism
- Diaphragm/pathology
- Drosophila Proteins/deficiency
- Drosophila Proteins/genetics
- Drosophila melanogaster/genetics
- Dystrophin-Associated Protein Complex/chemistry
- Exons
- Fibrosis
- Genetic Therapy
- HEK293 Cells
- Humans
- Mice
- Mice, Transgenic
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscular Dystrophies, Limb-Girdle/genetics
- Muscular Dystrophies, Limb-Girdle/therapy
- Muscular Dystrophy, Animal/genetics
- Muscular Dystrophy, Animal/pathology
- Muscular Dystrophy, Animal/therapy
- Mutation
- Myocardium/metabolism
- Myocardium/pathology
- Oligonucleotides, Antisense/pharmacology
- Oligonucleotides, Antisense/therapeutic use
- Protein Engineering
- Protein Interaction Mapping
- Protein Structure, Tertiary
- RNA, Messenger/chemistry
- RNA, Messenger/genetics
- Recombinant Fusion Proteins/metabolism
- Sarcoglycans/biosynthesis
- Sarcoglycans/chemistry
- Sarcoglycans/deficiency
- Sarcoglycans/genetics
- Sarcolemma/metabolism
- Sequence Deletion
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Holland A, Murphy S, Dowling P, Ohlendieck K. Pathoproteomic profiling of the skeletal muscle matrisome in dystrophinopathy associated myofibrosis. Proteomics 2015; 16:345-66. [PMID: 26256116 DOI: 10.1002/pmic.201500158] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 06/12/2015] [Accepted: 07/24/2015] [Indexed: 12/14/2022]
Abstract
The gradual accumulation of collagen and associated proteins of the extracellular matrix is a crucial myopathological parameter of many neuromuscular disorders. Progressive tissue damage and fibrosis play a key pathobiochemical role in the dysregulation of contractile functions and often correlates with poor motor outcome in muscular dystrophies. Following a brief introduction into the role of the extracellular matrix in skeletal muscles, we review here the proteomic profiling of myofibrosis and its intrinsic role in X-linked muscular dystrophy. Although Duchenne muscular dystrophy is primarily a disease of the membrane cytoskeleton, one of its most striking histopathological features is a hyperactive connective tissue and tissue scarring. We outline the identification of novel factors involved in the modulation of the extracellular matrix in muscular dystrophy, such as matricellular proteins. The establishment of novel proteomic markers will be helpful in improving the diagnosis, prognosis, and therapy monitoring in relation to fibrotic substitution of contractile tissue. In the future, the prevention of fibrosis will be crucial for providing optimum conditions to apply novel pharmacological treatments, as well as establish cell-based approaches or gene therapeutic interventions. The elimination of secondary abnormalities in the matrisome promises to reduce tissue scarring and the loss of skeletal muscle elasticity.
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Affiliation(s)
- Ashling Holland
- Department of Biology, Maynooth University, National University of Ireland, Maynooth, Co. Kildare, Ireland
| | - Sandra Murphy
- Department of Biology, Maynooth University, National University of Ireland, Maynooth, Co. Kildare, Ireland
| | - Paul Dowling
- Department of Biology, Maynooth University, National University of Ireland, Maynooth, Co. Kildare, Ireland
| | - Kay Ohlendieck
- Department of Biology, Maynooth University, National University of Ireland, Maynooth, Co. Kildare, Ireland
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48
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Genetic Engineering of Dystroglycan in Animal Models of Muscular Dystrophy. BIOMED RESEARCH INTERNATIONAL 2015; 2015:635792. [PMID: 26380289 PMCID: PMC4561298 DOI: 10.1155/2015/635792] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Accepted: 03/11/2015] [Indexed: 01/24/2023]
Abstract
In skeletal muscle, dystroglycan (DG) is the central component of the dystrophin-glycoprotein complex (DGC), a multimeric protein complex that ensures a strong mechanical link between the extracellular matrix and the cytoskeleton. Several muscular dystrophies arise from mutations hitting most of the components of the DGC. Mutations within the DG gene (DAG1) have been recently associated with two forms of muscular dystrophy, one displaying a milder and one a more severe phenotype. This review focuses specifically on the animal (murine and others) model systems that have been developed with the aim of directly engineering DAG1 in order to study the DG function in skeletal muscle as well as in other tissues. In the last years, conditional animal models overcoming the embryonic lethality of the DG knock-out in mouse have been generated and helped clarifying the crucial role of DG in skeletal muscle, while an increasing number of studies on knock-in mice are aimed at understanding the contribution of single amino acids to the stability of DG and to the possible development of muscular dystrophy.
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Abstract
Muscle fibres are very specialised cells with a complex structure that requires a high level of organisation of the constituent proteins. For muscle contraction to function properly, there is a need for not only sarcomeres, the contractile structures of the muscle fibre, but also costameres. These are supramolecular structures associated with the sarcolemma that allow muscle adhesion to the extracellular matrix. They are composed of protein complexes that interact and whose functions include maintaining cell structure and signal transduction mediated by their constituent proteins. It is important to improve our understanding of these structures, as mutations in various genes that code for costamere proteins cause many types of muscular dystrophy. In this review, we provide a description of costameres detailing each of their constituent proteins, such as dystrophin, dystrobrevin, syntrophin, sarcoglycans, dystroglycans, vinculin, talin, integrins, desmin, plectin, etc. We describe as well the diseases associated with deficiency thereof, providing a general overview of their importance.
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Biochemical and Functional Comparisons of mdx and Sgcg(-/-) Muscular Dystrophy Mouse Models. BIOMED RESEARCH INTERNATIONAL 2015; 2015:131436. [PMID: 26064876 PMCID: PMC4433636 DOI: 10.1155/2015/131436] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 01/13/2015] [Accepted: 01/13/2015] [Indexed: 12/31/2022]
Abstract
Mouse models have provided an essential platform to investigate facets of human diseases, from etiology, diagnosis, and prognosis, to potential treatments. Muscular dystrophy (MD) is the most common human genetic disease occurring in approximately 1 in 2500 births. The mdx mouse, which is dystrophin-deficient, has long been used to model this disease. However, this mouse strain displays a rather mild disease course compared to human patients. The mdx mice have been bred to additional genetically engineered mice to worsen the disease. Alternatively, other genes which cause human MD have been genetically disrupted in mice. We are now comparing disease progression from one of these alternative gene disruptions, the γ-sarcoglycan null mouse Sgcg−/− on the DBA2/J background, to the mdx mouse line. This paper aims to assess the time-course severity of the disease in the mouse models and determine which is best for MD research. The Sgcg−/− mice have a more severe phenotype than the mdx mice. Muscle function was assessed by plethysmography and echocardiography. Histologically the Sgcg−/− mice displayed increased fibrosis and variable fiber size. By quantitative Evan's blue dye uptake and hydroxyproline content two key disease determinants, membrane permeability and fibrosis respectively, were also proven worse in the Sgcg−/− mice.
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