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Moreno N, Sabater-Arcis M, Sevilla T, Alonso MP, Ohana J, Bargiela A, Artero R. Therapeutic potential of oleic acid supplementation in myotonic dystrophy muscle cell models. Biol Res 2024; 57:29. [PMID: 38760841 PMCID: PMC11100173 DOI: 10.1186/s40659-024-00496-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 04/05/2024] [Indexed: 05/19/2024] Open
Abstract
BACKGROUND We recently reported that upregulation of Musashi 2 (MSI2) protein in the rare neuromuscular disease myotonic dystrophy type 1 contributes to the hyperactivation of the muscle catabolic processes autophagy and UPS through a reduction in miR-7 levels. Because oleic acid (OA) is a known allosteric regulator of MSI2 activity in the biogenesis of miR-7, here we sought to evaluate endogenous levels of this fatty acid and its therapeutic potential in rescuing cell differentiation phenotypes in vitro. In this work, four muscle cell lines derived from DM1 patients were treated with OA for 24 h, and autophagy and muscle differentiation parameters were analyzed. RESULTS We demonstrate a reduction of OA levels in different cell models of the disease. OA supplementation rescued disease-related phenotypes such as fusion index, myotube diameter, and repressed autophagy. This involved inhibiting MSI2 regulation of direct molecular target miR-7 since OA isoschizomer, elaidic acid (EA) could not cause the same rescues. Reduction of OA levels seems to stem from impaired biogenesis since levels of the enzyme stearoyl-CoA desaturase 1 (SCD1), responsible for converting stearic acid to oleic acid, are decreased in DM1 and correlate with OA amounts. CONCLUSIONS For the first time in DM1, we describe a fatty acid metabolism impairment that originated, at least in part, from a decrease in SCD1. Because OA allosterically inhibits MSI2 binding to molecular targets, reduced OA levels synergize with the overexpression of MSI2 and contribute to the MSI2 > miR-7 > autophagy axis that we proposed to explain the muscle atrophy phenotype.
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Affiliation(s)
- Nerea Moreno
- Human Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain
- INCLIVA Biomedical Research Institute, Valencia, Spain
- CIBERER, IISCIII, Madrid, Spain
| | - Maria Sabater-Arcis
- Human Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain
- INCLIVA Biomedical Research Institute, Valencia, Spain
- CIBERER, IISCIII, Madrid, Spain
| | - Teresa Sevilla
- CIBERER, IISCIII, Madrid, Spain
- Neuromuscular and Ataxias Research Group, Health Research Institute Hospital, La Fe (IIS La Fe), Valencia, Spain
- Department of Medicine, University of Valencia, Valencia, Spain
| | - Manuel Perez Alonso
- Human Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain
- INCLIVA Biomedical Research Institute, Valencia, Spain
- CIBERER, IISCIII, Madrid, Spain
| | - Jessica Ohana
- Centre de Recherche en Myologie, Sorbonne Université, Inserm, Institut de Myologie, Paris, F-75013, France
| | - Ariadna Bargiela
- CIBERER, IISCIII, Madrid, Spain.
- Neuromuscular and Ataxias Research Group, Health Research Institute Hospital, La Fe (IIS La Fe), Valencia, Spain.
| | - Ruben Artero
- Human Translational Genomics Group, University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain
- INCLIVA Biomedical Research Institute, Valencia, Spain
- CIBERER, IISCIII, Madrid, Spain
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Aoussim A, Légaré C, Roussel MP, Madore AM, Morissette MC, Laprise C, Duchesne E. Towards the Identification of Biomarkers for Muscle Function Improvement in Myotonic Dystrophy Type 1. J Neuromuscul Dis 2023; 10:1041-1053. [PMID: 37694373 PMCID: PMC10657677 DOI: 10.3233/jnd-221645] [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] [Accepted: 08/15/2023] [Indexed: 09/12/2023]
Abstract
BACKGROUND Myotonic dystrophy type 1 (DM1) is the most common muscular dystrophy in adults. In DM1 patients, skeletal muscle is severely impaired, even atrophied and patients experience a progressive decrease in maximum strength. Strength training for these individuals can improve their muscle function and mass, however, the biological processes involved in these improvements remain unknown. OBJECTIVE This exploratory study aims at identifying the proteomic biomarkers and variables associated with the muscle proteome changes induced by training in DM1 individuals. METHODS An ion library was developed from liquid chromatography-tandem mass spectrometry proteomic analyses of Vastus Lateralis muscle biopsies collected in 11 individuals with DM1 pre-and post-training. RESULTS The proteomic analysis showed that the levels of 44 proteins were significantly modulated. A literature review (PubMed, UniProt, PANTHER, REACTOME) classified these proteins into biological sub-classes linked to training-induced response, including immunity, energy metabolism, apoptosis, insulin signaling, myogenesis and muscle contraction. Linear models identified key variables explaining the proteome modulation, including atrophy and hypertrophy factors. Finally, six proteins of interest involved in myogenesis, muscle contraction and insulin signaling were identified: calpain-3 (CAN3; Muscle development, positive regulation of satellite cell activation), 14-3-3 protein epsilon (1433E; Insulin/Insulin-like growth factor, PI3K/Akt signaling), myosin-binding protein H (MYBPH; Regulation of striated muscle contraction), four and a half LIM domains protein 3 (FHL3; Muscle organ development), filamin-C (FLNC; Muscle fiber development) and Cysteine and glycine-rich protein 3 (CSRP3). CONCLUSION These findings may lead to the identification for DM1 individuals of novel muscle biomarkers for clinical improvement induced by rehabilitation, which could eventually be used in combination with a targeted pharmaceutical approach to improving muscle function, but further studies are needed to confirm those results.
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Affiliation(s)
- Amira Aoussim
- Département des sciences de la santé, Université du Québec à Chicoutimi, Québec, Canada
- Groupe de recherche interdisciplinaire sur les maladies neuromusculaires (GRIMN), Centre intégré universitaire de santé et de services sociaux du Saguenay– Lac-Saint-Jean, Hôpital de Jonquière, Québec, Canada
- Centre intersectoriel en santé durable (CISD), Université du Québec à Chicoutimi, Québec, Canada
| | - Cécilia Légaré
- Département des sciences de la santé, Université du Québec à Chicoutimi, Québec, Canada
- Groupe de recherche interdisciplinaire sur les maladies neuromusculaires (GRIMN), Centre intégré universitaire de santé et de services sociaux du Saguenay– Lac-Saint-Jean, Hôpital de Jonquière, Québec, Canada
- Centre intersectoriel en santé durable (CISD), Université du Québec à Chicoutimi, Québec, Canada
- RNA Institute, College of Arts and Sciences, University at Albany-SUNY, Albany, USA
| | - Marie-Pier Roussel
- Groupe de recherche interdisciplinaire sur les maladies neuromusculaires (GRIMN), Centre intégré universitaire de santé et de services sociaux du Saguenay– Lac-Saint-Jean, Hôpital de Jonquière, Québec, Canada
- Centre intersectoriel en santé durable (CISD), Université du Québec à Chicoutimi, Québec, Canada
- Département des sciences fondamentales, Université du Québec à Chicoutimi, Québec, Canada
| | - Anne-Marie Madore
- Centre intersectoriel en santé durable (CISD), Université du Québec à Chicoutimi, Québec, Canada
- Département des sciences fondamentales, Université du Québec à Chicoutimi, Québec, Canada
| | - Mathieu C. Morissette
- Department of Medicine, Université Laval, Québec, Canada
- Quebec Heart and Lung Institute – Université Laval, Québec, Canada
| | - Catherine Laprise
- Centre intersectoriel en santé durable (CISD), Université du Québec à Chicoutimi, Québec, Canada
- Département des sciences fondamentales, Université du Québec à Chicoutimi, Québec, Canada
| | - Elise Duchesne
- Département des sciences de la santé, Université du Québec à Chicoutimi, Québec, Canada
- Groupe de recherche interdisciplinaire sur les maladies neuromusculaires (GRIMN), Centre intégré universitaire de santé et de services sociaux du Saguenay– Lac-Saint-Jean, Hôpital de Jonquière, Québec, Canada
- Centre intersectoriel en santé durable (CISD), Université du Québec à Chicoutimi, Québec, Canada
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Ribot C, Soler C, Chartier A, Al Hayek S, Naït-Saïdi R, Barbezier N, Coux O, Simonelig M. Activation of the ubiquitin-proteasome system contributes to oculopharyngeal muscular dystrophy through muscle atrophy. PLoS Genet 2022; 18:e1010015. [PMID: 35025870 PMCID: PMC8791501 DOI: 10.1371/journal.pgen.1010015] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 01/26/2022] [Accepted: 01/01/2022] [Indexed: 12/05/2022] Open
Abstract
Oculopharyngeal muscular dystrophy (OPMD) is a late-onset disorder characterized by progressive weakness and degeneration of specific muscles. OPMD is due to extension of a polyalanine tract in poly(A) binding protein nuclear 1 (PABPN1). Aggregation of the mutant protein in muscle nuclei is a hallmark of the disease. Previous transcriptomic analyses revealed the consistent deregulation of the ubiquitin-proteasome system (UPS) in OPMD animal models and patients, suggesting a role of this deregulation in OPMD pathogenesis. Subsequent studies proposed that UPS contribution to OPMD involved PABPN1 aggregation. Here, we use a Drosophila model of OPMD to address the functional importance of UPS deregulation in OPMD. Through genome-wide and targeted genetic screens we identify a large number of UPS components that are involved in OPMD. Half dosage of UPS genes reduces OPMD muscle defects suggesting a pathological increase of UPS activity in the disease. Quantification of proteasome activity confirms stronger activity in OPMD muscles, associated with degradation of myofibrillar proteins. Importantly, improvement of muscle structure and function in the presence of UPS mutants does not correlate with the levels of PABPN1 aggregation, but is linked to decreased degradation of muscle proteins. Oral treatment with the proteasome inhibitor MG132 is beneficial to the OPMD Drosophila model, improving muscle function although PABPN1 aggregation is enhanced. This functional study reveals the importance of increased UPS activity that underlies muscle atrophy in OPMD. It also provides a proof-of-concept that inhibitors of proteasome activity might be an attractive pharmacological approach for OPMD. Oculopharyngeal muscular dystrophy (OPMD) is a genetic disease characterized by progressive weakness of specific muscles, leading to swallowing difficulties (dysphagia), eyelid drooping (ptosis) and walking difficulties at later stages. No drug treatments are currently available. OPMD is due to mutations in a nuclear protein called poly(A) binding protein nuclear 1 (PABPN1) that is involved in processing of different classes of RNAs in the nucleus. We have used an animal model of OPMD that we have developed in the fly Drosophila to investigate the role in OPMD of the ubiquitin-proteasome system, a pathway specialized in protein degradation. We report an increased activity of the ubiquitin-proteasome system that is associated with degradation of muscular proteins in the OPMD Drosophila model. We propose that higher activity of the ubiquitin-proteasome system leads to muscle atrophy in OPMD. Importantly, oral treatment of this OPMD animal model with an inhibitor of proteasome activity reduces muscle defects. A number of proteasome inhibitors are approved drugs used in clinic against cancers, therefore our results provide a proof-of-concept that inhibitors of proteasome might be of interest in future treatments of OPMD.
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Affiliation(s)
- Cécile Ribot
- mRNA Regulation and Development, Institute of Human Genetics, UMR9002 CNRS-Univ Montpellier, Montpellier, France
| | - Cédric Soler
- mRNA Regulation and Development, Institute of Human Genetics, UMR9002 CNRS-Univ Montpellier, Montpellier, France
| | - Aymeric Chartier
- mRNA Regulation and Development, Institute of Human Genetics, UMR9002 CNRS-Univ Montpellier, Montpellier, France
| | - Sandy Al Hayek
- GReD Laboratory, Clermont-Auvergne University, INSERM U1103, CNRS UMR6293, Clermont-Ferrand, France
| | - Rima Naït-Saïdi
- mRNA Regulation and Development, Institute of Human Genetics, UMR9002 CNRS-Univ Montpellier, Montpellier, France
| | - Nicolas Barbezier
- mRNA Regulation and Development, Institute of Human Genetics, UMR9002 CNRS-Univ Montpellier, Montpellier, France
| | - Olivier Coux
- Ubiquitin-proteasome system and cell cycle control, Montpellier Cell Biology Research Center, UMR5237 CNRS-Univ Montpellier, Montpellier, France
| | - Martine Simonelig
- mRNA Regulation and Development, Institute of Human Genetics, UMR9002 CNRS-Univ Montpellier, Montpellier, France
- * E-mail:
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Fralish Z, Lotz EM, Chavez T, Khodabukus A, Bursac N. Neuromuscular Development and Disease: Learning From in vitro and in vivo Models. Front Cell Dev Biol 2021; 9:764732. [PMID: 34778273 PMCID: PMC8579029 DOI: 10.3389/fcell.2021.764732] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/06/2021] [Indexed: 01/02/2023] Open
Abstract
The neuromuscular junction (NMJ) is a specialized cholinergic synaptic interface between a motor neuron and a skeletal muscle fiber that translates presynaptic electrical impulses into motor function. NMJ formation and maintenance require tightly regulated signaling and cellular communication among motor neurons, myogenic cells, and Schwann cells. Neuromuscular diseases (NMDs) can result in loss of NMJ function and motor input leading to paralysis or even death. Although small animal models have been instrumental in advancing our understanding of the NMJ structure and function, the complexities of studying this multi-tissue system in vivo and poor clinical outcomes of candidate therapies developed in small animal models has driven the need for in vitro models of functional human NMJ to complement animal studies. In this review, we discuss prevailing models of NMDs and highlight the current progress and ongoing challenges in developing human iPSC-derived (hiPSC) 3D cell culture models of functional NMJs. We first review in vivo development of motor neurons, skeletal muscle, Schwann cells, and the NMJ alongside current methods for directing the differentiation of relevant cell types from hiPSCs. We further compare the efficacy of modeling NMDs in animals and human cell culture systems in the context of five NMDs: amyotrophic lateral sclerosis, myasthenia gravis, Duchenne muscular dystrophy, myotonic dystrophy, and Pompe disease. Finally, we discuss further work necessary for hiPSC-derived NMJ models to function as effective personalized NMD platforms.
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Affiliation(s)
- Zachary Fralish
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Ethan M Lotz
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Taylor Chavez
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Alastair Khodabukus
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
| | - Nenad Bursac
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, United States
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Pascual-Gilabert M, López-Castel A, Artero R. Myotonic dystrophy type 1 drug development: A pipeline toward the market. Drug Discov Today 2021; 26:1765-1772. [PMID: 33798646 PMCID: PMC8372527 DOI: 10.1016/j.drudis.2021.03.024] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/28/2021] [Accepted: 03/23/2021] [Indexed: 01/12/2023]
Abstract
Myotonic dystrophy type 1 (DM1) is a multisystemic neuromuscular genetic disease with an estimated prevalence of approximately at least half a million individuals based on its vast ethnic variation. Building upon a well-known physiopathology and several proof-of-concept therapeutic approaches, herein we compile a comprehensive overview of the most recent drug development programs under preclinical and clinical evaluation. Specifically, close to two dozen drug developments, eight of which are already in clinical trials, explore a diversity of new chemical entities, drug repurposing, oligonucleotide, and gene therapy-based approaches. Of these, repurposing of tideglusib, mexiletine, or metformin appear to be therapies with the most potential to receive marketing authorization for DM1.
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Affiliation(s)
| | - Arturo López-Castel
- University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain; Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain; Joint Unit Incliva-CIPF, Valencia, Spain.
| | - Ruben Artero
- University Institute for Biotechnology and Biomedicine (BIOTECMED), University of Valencia, Valencia, Spain; Translational Genomics Group, Incliva Health Research Institute, Valencia, Spain; Joint Unit Incliva-CIPF, Valencia, Spain
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6
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Ozimski LL, Sabater-Arcis M, Bargiela A, Artero R. The hallmarks of myotonic dystrophy type 1 muscle dysfunction. Biol Rev Camb Philos Soc 2020; 96:716-730. [PMID: 33269537 DOI: 10.1111/brv.12674] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 11/18/2020] [Accepted: 11/20/2020] [Indexed: 12/20/2022]
Abstract
Myotonic dystrophy type 1 (DM1) is the most prevalent form of muscular dystrophy in adults and yet there are currently no treatment options. Although this disease causes multisystemic symptoms, it is mainly characterised by myopathy or diseased muscles, which includes muscle weakness, atrophy, and myotonia, severely affecting the lives of patients worldwide. On a molecular level, DM1 is caused by an expansion of CTG repeats in the 3' untranslated region (3'UTR) of the DM1 Protein Kinase (DMPK) gene which become pathogenic when transcribed into RNA forming ribonuclear foci comprised of auto complementary CUG hairpin structures that can bind proteins. This leads to the sequestration of the muscleblind-like (MBNL) family of proteins, depleting them, and the abnormal stabilisation of CUGBP Elav-like family member 1 (CELF1), enhancing it. Traditionally, DM1 research has focused on this RNA toxicity and how it alters MBNL and CELF1 functions as key splicing regulators. However, other proteins are affected by the toxic DMPK RNA and there is strong evidence that supports various signalling cascades playing an important role in DM1 pathogenesis. Specifically, the impairment of protein kinase B (AKT) signalling in DM1 increases autophagy, apoptosis, and ubiquitin-proteasome activity, which may also be affected in DM1 by AMP-activated protein kinase (AMPK) downregulation. AKT also regulates CELF1 directly, by affecting its subcellular localisation, and indirectly as it inhibits glycogen synthase kinase 3 beta (GSK3β), which stabilises the repressive form of CELF1 in DM1. Another kinase that contributes to CELF1 mis-regulation, in this case by hyperphosphorylation, is protein kinase C (PKC). Additionally, it has been demonstrated that fibroblast growth factor-inducible 14 (Fn14) is induced in DM1 and is associated with downstream signalling through the nuclear factor κB (NFκB) pathways, associating inflammation with this disease. Furthermore, MBNL1 and CELF1 play a role in cytoplasmic processes involved in DM1 myopathy, altering proteostasis and sarcomere structure. Finally, there are many other elements that could contribute to the muscular phenotype in DM1 such as alterations to satellite cells, non-coding RNA metabolism, calcium dysregulation, and repeat-associated non-ATG (RAN) translation. This review aims to organise the currently dispersed knowledge on the different pathways affected in DM1 and discusses the unexplored connections that could potentially help in providing new therapeutic targets in DM1 research.
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Affiliation(s)
- Lauren L Ozimski
- Translational Genomics Group, Incliva Health Research Institute, Avda. Menéndez Pelayo 4 acc., Valencia, 46010, Spain.,University Institute for Biotechnology and Biomedicine, Dr. Moliner 50, Burjasot, Valencia, 46100, Spain.,CIPF-INCLIVA Joint Unit, Valencia, 46012, Spain.,Arthex Biotech, Catedrático Escardino, 9, Paterna, Valencia, 46980, Spain
| | - Maria Sabater-Arcis
- Translational Genomics Group, Incliva Health Research Institute, Avda. Menéndez Pelayo 4 acc., Valencia, 46010, Spain.,University Institute for Biotechnology and Biomedicine, Dr. Moliner 50, Burjasot, Valencia, 46100, Spain.,CIPF-INCLIVA Joint Unit, Valencia, 46012, Spain
| | - Ariadna Bargiela
- Translational Genomics Group, Incliva Health Research Institute, Avda. Menéndez Pelayo 4 acc., Valencia, 46010, Spain.,University Institute for Biotechnology and Biomedicine, Dr. Moliner 50, Burjasot, Valencia, 46100, Spain.,CIPF-INCLIVA Joint Unit, Valencia, 46012, Spain
| | - Ruben Artero
- Translational Genomics Group, Incliva Health Research Institute, Avda. Menéndez Pelayo 4 acc., Valencia, 46010, Spain.,University Institute for Biotechnology and Biomedicine, Dr. Moliner 50, Burjasot, Valencia, 46100, Spain.,CIPF-INCLIVA Joint Unit, Valencia, 46012, Spain
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The Ubiquitin Proteasome System in Neuromuscular Disorders: Moving Beyond Movement. Int J Mol Sci 2020; 21:ijms21176429. [PMID: 32899400 PMCID: PMC7503226 DOI: 10.3390/ijms21176429] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/30/2020] [Accepted: 08/31/2020] [Indexed: 12/12/2022] Open
Abstract
Neuromuscular disorders (NMDs) affect 1 in 3000 people worldwide. There are more than 150 different types of NMDs, where the common feature is the loss of muscle strength. These disorders are classified according to their neuroanatomical location, as motor neuron diseases, peripheral nerve diseases, neuromuscular junction diseases, and muscle diseases. Over the years, numerous studies have pointed to protein homeostasis as a crucial factor in the development of these fatal diseases. The ubiquitin-proteasome system (UPS) plays a fundamental role in maintaining protein homeostasis, being involved in protein degradation, among other cellular functions. Through a cascade of enzymatic reactions, proteins are ubiquitinated, tagged, and translocated to the proteasome to be degraded. Within the ubiquitin system, we can find three main groups of enzymes: E1 (ubiquitin-activating enzymes), E2 (ubiquitin-conjugating enzymes), and E3 (ubiquitin-protein ligases). Only the ubiquitinated proteins with specific chain linkages (such as K48) will be degraded by the UPS. In this review, we describe the relevance of this system in NMDs, summarizing the UPS proteins that have been involved in pathological conditions and neuromuscular disorders, such as Spinal Muscular Atrophy (SMA), Charcot-Marie-Tooth disease (CMT), or Duchenne Muscular Dystrophy (DMD), among others. A better knowledge of the processes involved in the maintenance of proteostasis may pave the way for future progress in neuromuscular disorder studies and treatments.
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Crawford Parks TE, Marcellus KA, Péladeau C, Jasmin BJ, Ravel-Chapuis A. Overexpression of Staufen1 in DM1 mouse skeletal muscle exacerbates dystrophic and atrophic features. Hum Mol Genet 2020; 29:2185-2199. [PMID: 32504084 DOI: 10.1093/hmg/ddaa111] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 05/15/2020] [Accepted: 05/27/2020] [Indexed: 12/15/2022] Open
Abstract
In myotonic dystrophy type 1 (DM1), the CUG expansion (CUGexp) in the 3' untranslated region of the dystrophia myotonica protein kinase messenger ribonucleic acid affects the homeostasis of ribonucleic acid-binding proteins, causing the multiple symptoms of DM1. We have previously reported that Staufen1 is increased in skeletal muscles from DM1 mice and patients and that sustained Staufen1 expression in mature mouse muscle causes a progressive myopathy. Here, we hypothesized that the elevated levels of Staufen1 contributes to the myopathic features of the disease. Interestingly, the classic DM1 mouse model human skeletal actin long repeat (HSALR) lacks overt atrophy while expressing CUGexp transcripts and elevated levels of endogenous Staufen1, suggesting a lower sensitivity to atrophic signaling in this model. We report that further overexpression of Staufen1 in the DM1 mouse model HSALR causes a myopathy via inhibition of protein kinase B signaling through an increase in phosphatase tensin homolog, leading to the expression of atrogenes. Interestingly, we also show that Staufen1 regulates the expression of muscleblind-like splicing regulator 1 and CUG-binding protein elav-like family member 1 in wild-type and DM1 skeletal muscle. Together, data obtained from these new DM1 mouse models provide evidence for the role of Staufen1 as an atrophy-associated gene that impacts progressive muscle wasting in DM1. Accordingly, our findings highlight the potential of Staufen1 as a therapeutic target and biomarker.
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Affiliation(s)
- Tara E Crawford Parks
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada.,Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Kristen A Marcellus
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada.,Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Christine Péladeau
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada.,Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Bernard J Jasmin
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada.,Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Aymeric Ravel-Chapuis
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada.,Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
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9
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Sabater-Arcis M, Bargiela A, Furling D, Artero R. miR-7 Restores Phenotypes in Myotonic Dystrophy Muscle Cells by Repressing Hyperactivated Autophagy. MOLECULAR THERAPY. NUCLEIC ACIDS 2019; 19:278-292. [PMID: 31855836 PMCID: PMC6926285 DOI: 10.1016/j.omtn.2019.11.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 11/08/2019] [Accepted: 11/08/2019] [Indexed: 12/16/2022]
Abstract
Unstable CTG expansions in the 3’ UTR of the DMPK gene are responsible for myotonic dystrophy type 1 (DM1) condition. Muscle dysfunction is one of the main contributors to DM1 mortality and morbidity. Pathways by which mutant DMPK trigger muscle defects, however, are not fully understood. We previously reported that miR-7 was downregulated in a DM1 Drosophila model and in biopsies from patients. Here, using DM1 and normal muscle cells, we investigated whether miR-7 contributes to the muscle phenotype by studying the consequences of replenishing or blocking miR-7, respectively. Restoration of miR-7 with agomiR-7 was sufficient to rescue DM1 myoblast fusion defects and myotube growth. Conversely, oligonucleotide-mediated blocking of miR-7 in normal myoblasts led to fusion and myotube growth defects. miR-7 was found to regulate autophagy and the ubiquitin-proteasome system in human muscle cells. Thus, low levels of miR-7 promoted both processes, and high levels of miR-7 repressed them. Furthermore, we uncovered that the mechanism by which miR-7 improves atrophy-related phenotypes is independent of MBNL1, thus suggesting that miR-7 acts downstream or in parallel to MBNL1. Collectively, these results highlight an unknown function for miR-7 in muscle dysfunction through autophagy- and atrophy-related pathways and support that restoration of miR-7 levels is a candidate therapeutic target for counteracting muscle dysfunction in DM1.
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Affiliation(s)
- Maria Sabater-Arcis
- Translational Genomics Group, Incliva Health Research Institute, Valencia 46100, Spain; Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), University of Valencia, Valencia 46100, Spain; CIPF-INCLIVA Joint Unit, Valencia 46012, Spain
| | - Ariadna Bargiela
- Translational Genomics Group, Incliva Health Research Institute, Valencia 46100, Spain; Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), University of Valencia, Valencia 46100, Spain; CIPF-INCLIVA Joint Unit, Valencia 46012, Spain.
| | - Denis Furling
- Sorbonne Université, Inserm, Association Institut de Myologie, Centre de Recherche en Myologie, Paris 75013, France
| | - Ruben Artero
- Translational Genomics Group, Incliva Health Research Institute, Valencia 46100, Spain; Interdisciplinary Research Structure for Biotechnology and Biomedicine (ERI BIOTECMED), University of Valencia, Valencia 46100, Spain; CIPF-INCLIVA Joint Unit, Valencia 46012, Spain
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Zhang Y, Long C, Bassel-Duby R, Olson EN. Myoediting: Toward Prevention of Muscular Dystrophy by Therapeutic Genome Editing. Physiol Rev 2018; 98:1205-1240. [PMID: 29717930 DOI: 10.1152/physrev.00046.2017] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Muscular dystrophies represent a large group of genetic disorders that significantly impair quality of life and often progress to premature death. There is no effective treatment for these debilitating diseases. Most therapies, developed to date, focus on alleviating the symptoms or targeting the secondary effects, while the underlying gene mutation is still present in the human genome. The discovery and application of programmable nucleases for site-specific DNA double-stranded breaks provides a powerful tool for precise genome engineering. In particular, the CRISPR/Cas system has revolutionized the genome editing field and is providing a new path for disease treatment by targeting the disease-causing genetic mutations. In this review, we provide a historical overview of genome-editing technologies, summarize the most recent advances, and discuss potential strategies and challenges for permanently correcting genetic mutations that cause muscular dystrophies.
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Affiliation(s)
- Yu Zhang
- Department of Molecular Biology, Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center and Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Chengzu Long
- Department of Molecular Biology, Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center and Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Rhonda Bassel-Duby
- Department of Molecular Biology, Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center and Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Eric N Olson
- Department of Molecular Biology, Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center and Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center , Dallas, Texas
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11
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Meinke P, Hintze S, Limmer S, Schoser B. Myotonic Dystrophy-A Progeroid Disease? Front Neurol 2018; 9:601. [PMID: 30140252 PMCID: PMC6095001 DOI: 10.3389/fneur.2018.00601] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 07/06/2018] [Indexed: 12/27/2022] Open
Abstract
Myotonic dystrophies (DM) are slowly progressing multisystemic disorders caused by repeat expansions in the DMPK or CNBP genes. The multisystemic involvement in DM patients often reflects the appearance of accelerated aging. This is partly due to visible features such as cataracts, muscle weakness, and frontal baldness, but there are also less obvious features like cardiac arrhythmia, diabetes or hypogammaglobulinemia. These aging features suggest the hypothesis that DM could be a segmental progeroid disease. To identify the molecular cause of this characteristic appearance of accelerated aging we compare clinical features of DM to “typical” segmental progeroid disorders caused by mutations in DNA repair or nuclear envelope proteins. Furthermore, we characterize if this premature aging effect is also reflected on the cellular level in DM and investigate overlaps with “classical” progeroid disorders. To investigate the molecular similarities at the cellular level we use primary DM and control cell lines. This analysis reveals many similarities to progeroid syndromes linked to the nuclear envelope. Our comparison on both clinical and molecular levels argues for qualification of DM as a segmental progeroid disorder.
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Affiliation(s)
- Peter Meinke
- Friedrich-Baur-Institute at the Department of Neurology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Stefan Hintze
- Friedrich-Baur-Institute at the Department of Neurology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Sarah Limmer
- Friedrich-Baur-Institute at the Department of Neurology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Benedikt Schoser
- Friedrich-Baur-Institute at the Department of Neurology, University Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
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12
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Braz SO, Acquaire J, Gourdon G, Gomes-Pereira M. Of Mice and Men: Advances in the Understanding of Neuromuscular Aspects of Myotonic Dystrophy. Front Neurol 2018; 9:519. [PMID: 30050493 PMCID: PMC6050950 DOI: 10.3389/fneur.2018.00519] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2018] [Accepted: 06/12/2018] [Indexed: 12/26/2022] Open
Abstract
Intensive effort has been directed toward the modeling of myotonic dystrophy (DM) in mice, in order to reproduce human disease and to provide useful tools to investigate molecular and cellular pathogenesis and test efficient therapies. Mouse models have contributed to dissect the multifaceted impact of the DM mutation in various tissues, cell types and in a pleiotropy of pathways, through the expression of toxic RNA transcripts. Changes in alternative splicing, transcription, translation, intracellular RNA localization, polyadenylation, miRNA metabolism and phosphorylation of disease intermediates have been described in different tissues. Some of these events have been directly associated with specific disease symptoms in the skeletal muscle and heart of mice, offering the molecular explanation for individual disease phenotypes. In the central nervous system (CNS), however, the situation is more complex. We still do not know how the molecular abnormalities described translate into CNS dysfunction, nor do we know if the correction of individual molecular events will provide significant therapeutic benefits. The variability in model design and phenotypes described so far requires a thorough and critical analysis. In this review we discuss the recent contributions of mouse models to the understanding of neuromuscular aspects of disease, therapy development, and we provide a reflective assessment of our current limitations and pressing questions that remain unanswered.
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Affiliation(s)
- Sandra O Braz
- Laboratory CTGDM, INSERM UMR1163, Paris, France.,Institut Imagine, Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Julien Acquaire
- Laboratory CTGDM, INSERM UMR1163, Paris, France.,Institut Imagine, Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Geneviève Gourdon
- Laboratory CTGDM, INSERM UMR1163, Paris, France.,Institut Imagine, Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Mário Gomes-Pereira
- Laboratory CTGDM, INSERM UMR1163, Paris, France.,Institut Imagine, Université Paris Descartes-Sorbonne Paris Cité, Paris, France
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13
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Thomas JD, Oliveira R, Sznajder ŁJ, Swanson MS. Myotonic Dystrophy and Developmental Regulation of RNA Processing. Compr Physiol 2018; 8:509-553. [PMID: 29687899 PMCID: PMC11323716 DOI: 10.1002/cphy.c170002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Myotonic dystrophy (DM) is a multisystemic disorder caused by microsatellite expansion mutations in two unrelated genes leading to similar, yet distinct, diseases. DM disease presentation is highly variable and distinguished by differences in age-of-onset and symptom severity. In the most severe form, DM presents with congenital onset and profound developmental defects. At the molecular level, DM pathogenesis is characterized by a toxic RNA gain-of-function mechanism that involves the transcription of noncoding microsatellite expansions. These mutant RNAs disrupt key cellular pathways, including RNA processing, localization, and translation. In DM, these toxic RNA effects are predominantly mediated through the modulation of the muscleblind-like and CUGBP and ETR-3-like factor families of RNA binding proteins (RBPs). Dysfunction of these RBPs results in widespread RNA processing defects culminating in the expression of developmentally inappropriate protein isoforms in adult tissues. The tissue that is the focus of this review, skeletal muscle, is particularly sensitive to mutant RNA-responsive perturbations, as patients display a variety of developmental, structural, and functional defects in muscle. Here, we provide a comprehensive overview of DM1 and DM2 clinical presentation and pathology as well as the underlying cellular and molecular defects associated with DM disease onset and progression. Additionally, fundamental aspects of skeletal muscle development altered in DM are highlighted together with ongoing and potential therapeutic avenues to treat this muscular dystrophy. © 2018 American Physiological Society. Compr Physiol 8:509-553, 2018.
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Affiliation(s)
- James D. Thomas
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, Florida, USA
| | - Ruan Oliveira
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, Florida, USA
| | - Łukasz J. Sznajder
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, Florida, USA
| | - Maurice S. Swanson
- Department of Molecular Genetics and Microbiology, Center for NeuroGenetics and the Genetics Institute, University of Florida, College of Medicine, Gainesville, Florida, USA
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14
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Crawford Parks TE, Ravel-Chapuis A, Bondy-Chorney E, Renaud JM, Côté J, Jasmin BJ. Muscle-specific expression of the RNA-binding protein Staufen1 induces progressive skeletal muscle atrophy via regulation of phosphatase tensin homolog. Hum Mol Genet 2017; 26:1821-1838. [PMID: 28369467 DOI: 10.1093/hmg/ddx085] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 03/02/2017] [Indexed: 12/14/2022] Open
Abstract
Converging lines of evidence have now highlighted the key role for post-transcriptional regulation in the neuromuscular system. In particular, several RNA-binding proteins are known to be misregulated in neuromuscular disorders including myotonic dystrophy type 1, spinal muscular atrophy and amyotrophic lateral sclerosis. In this study, we focused on the RNA-binding protein Staufen1, which assumes multiple functions in both skeletal muscle and neurons. Given our previous work that showed a marked increase in Staufen1 expression in various physiological and pathological conditions including denervated muscle, in embryonic and undifferentiated skeletal muscle, in rhabdomyosarcomas as well as in myotonic dystrophy type 1 muscle samples from both mouse models and humans, we investigated the impact of sustained Staufen1 expression in postnatal skeletal muscle. To this end, we generated a skeletal muscle-specific transgenic mouse model using the muscle creatine kinase promoter to drive tissue-specific expression of Staufen1. We report that sustained Staufen1 expression in postnatal skeletal muscle causes a myopathy characterized by significant morphological and functional deficits. These deficits are accompanied by a marked increase in the expression of several atrophy-associated genes and by the negative regulation of PI3K/AKT signaling. We also uncovered that Staufen1 mediates PTEN expression through indirect transcriptional and direct post-transcriptional events thereby providing the first evidence for Staufen1-regulated PTEN expression. Collectively, our data demonstrate that Staufen1 is a novel atrophy-associated gene, and highlight its potential as a biomarker and therapeutic target for neuromuscular disorders and conditions.
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Affiliation(s)
- Tara E Crawford Parks
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Aymeric Ravel-Chapuis
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Emma Bondy-Chorney
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Jean-Marc Renaud
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Jocelyn Côté
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Bernard J Jasmin
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
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15
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Expanded CCUG repeat RNA expression in Drosophila heart and muscle trigger Myotonic Dystrophy type 1-like phenotypes and activate autophagocytosis genes. Sci Rep 2017; 7:2843. [PMID: 28588248 PMCID: PMC5460254 DOI: 10.1038/s41598-017-02829-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 04/19/2017] [Indexed: 12/12/2022] Open
Abstract
Myotonic dystrophies (DM1–2) are neuromuscular genetic disorders caused by the pathological expansion of untranslated microsatellites. DM1 and DM2, are caused by expanded CTG repeats in the 3′UTR of the DMPK gene and CCTG repeats in the first intron of the CNBP gene, respectively. Mutant RNAs containing expanded repeats are retained in the cell nucleus, where they sequester nuclear factors and cause alterations in RNA metabolism. However, for unknown reasons, DM1 is more severe than DM2. To study the differences and similarities in the pathogenesis of DM1 and DM2, we generated model flies by expressing pure expanded CUG ([250]×) or CCUG ([1100]×) repeats, respectively, and compared them with control flies expressing either 20 repeat units or GFP. We observed surprisingly severe muscle reduction and cardiac dysfunction in CCUG-expressing model flies. The muscle and cardiac tissue of both DM1 and DM2 model flies showed DM1-like phenotypes including overexpression of autophagy-related genes, RNA mis-splicing and repeat RNA aggregation in ribonuclear foci along with the Muscleblind protein. These data reveal, for the first time, that expanded non-coding CCUG repeat-RNA has similar in vivo toxicity potential as expanded CUG RNA in muscle and heart tissues and suggests that specific, as yet unknown factors, quench CCUG-repeat toxicity in DM2 patients.
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16
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Jauvin D, Chrétien J, Pandey SK, Martineau L, Revillod L, Bassez G, Lachon A, MacLeod AR, Gourdon G, Wheeler TM, Thornton CA, Bennett CF, Puymirat J. Targeting DMPK with Antisense Oligonucleotide Improves Muscle Strength in Myotonic Dystrophy Type 1 Mice. MOLECULAR THERAPY. NUCLEIC ACIDS 2017. [PMID: 28624222 PMCID: PMC5453865 DOI: 10.1016/j.omtn.2017.05.007] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Myotonic dystrophy type 1 (DM1), a dominant hereditary muscular dystrophy, is caused by an abnormal expansion of a (CTG)n trinucleotide repeat in the 3′ UTR of the human dystrophia myotonica protein kinase (DMPK) gene. As a consequence, mutant transcripts containing expanded CUG repeats are retained in nuclear foci and alter the function of splicing regulatory factors members of the MBNL and CELF families, resulting in alternative splicing misregulation of specific transcripts in affected DM1 tissues. In the present study, we treated DMSXL mice systemically with a 2′-4′-constrained, ethyl-modified (ISIS 486178) antisense oligonucleotide (ASO) targeted to the 3′ UTR of the DMPK gene, which led to a 70% reduction in CUGexp RNA abundance and foci in different skeletal muscles and a 30% reduction in the heart. Furthermore, treatment with ISIS 486178 ASO improved body weight, muscle strength, and muscle histology, whereas no overt toxicity was detected. This is evidence that the reduction of CUGexp RNA improves muscle strength in DM1, suggesting that muscle weakness in DM1 patients may be improved following elimination of toxic RNAs.
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Affiliation(s)
- Dominic Jauvin
- Laval University Experimental Organogenesis Center/LOEX, Enfant-Jésus Hospital, Québec, QC G1J 1Z4, Canada
| | - Jessina Chrétien
- Laval University Experimental Organogenesis Center/LOEX, Enfant-Jésus Hospital, Québec, QC G1J 1Z4, Canada
| | - Sanjay K Pandey
- Ionis Pharmaceuticals, Inc., Carlsbad, CA 92010, USA; Triangulum Biopharma, San Diego, CA 92121, USA
| | - Laurie Martineau
- Laval University Experimental Organogenesis Center/LOEX, Enfant-Jésus Hospital, Québec, QC G1J 1Z4, Canada
| | - Lucille Revillod
- INSERM U955, Neuromuscular Reference Center, Henri-Mondor Hospital, Créteil 94000, France
| | - Guillaume Bassez
- INSERM U955, Neuromuscular Reference Center, Henri-Mondor Hospital, Créteil 94000, France
| | - Aline Lachon
- INSERM U781, Imagine Institute, Paris 75015, France
| | | | | | | | | | | | - Jack Puymirat
- Laval University Experimental Organogenesis Center/LOEX, Enfant-Jésus Hospital, Québec, QC G1J 1Z4, Canada; Department of Neurological Sciences CHU de Québec-Laval University, Enfant-Jésus Hospital, Québec, QC G1J 1Z4, Canada.
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17
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Brockhoff M, Rion N, Chojnowska K, Wiktorowicz T, Eickhorst C, Erne B, Frank S, Angelini C, Furling D, Rüegg MA, Sinnreich M, Castets P. Targeting deregulated AMPK/mTORC1 pathways improves muscle function in myotonic dystrophy type I. J Clin Invest 2017; 127:549-563. [PMID: 28067669 DOI: 10.1172/jci89616] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 11/17/2016] [Indexed: 12/13/2022] Open
Abstract
Myotonic dystrophy type I (DM1) is a disabling multisystemic disease that predominantly affects skeletal muscle. It is caused by expanded CTG repeats in the 3'-UTR of the dystrophia myotonica protein kinase (DMPK) gene. RNA hairpins formed by elongated DMPK transcripts sequester RNA-binding proteins, leading to mis-splicing of numerous pre-mRNAs. Here, we have investigated whether DM1-associated muscle pathology is related to deregulation of central metabolic pathways, which may identify potential therapeutic targets for the disease. In a well-characterized mouse model for DM1 (HSALR mice), activation of AMPK signaling in muscle was impaired under starved conditions, while mTORC1 signaling remained active. In parallel, autophagic flux was perturbed in HSALR muscle and in cultured human DM1 myotubes. Pharmacological approaches targeting AMPK/mTORC1 signaling greatly ameliorated muscle function in HSALR mice. AICAR, an AMPK activator, led to a strong reduction of myotonia, which was accompanied by partial correction of misregulated alternative splicing. Rapamycin, an mTORC1 inhibitor, improved muscle relaxation and increased muscle force in HSALR mice without affecting splicing. These findings highlight the involvement of AMPK/mTORC1 deregulation in DM1 muscle pathophysiology and may open potential avenues for the treatment of this disease.
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18
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Membrane repair of human skeletal muscle cells requires Annexin-A5. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:2267-79. [PMID: 27286750 DOI: 10.1016/j.bbamcr.2016.06.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 05/31/2016] [Accepted: 06/03/2016] [Indexed: 11/20/2022]
Abstract
Defect in membrane repair contributes to the development of limb girdle muscular dystrophy type 2B (LGMD2B) and Miyoshi myopathy. In healthy skeletal muscle, unraveling membrane repair mechanisms requires to establish an exhaustive list of the components of the resealing machinery. Here we show that human myotubes rendered deficient for Annexin-A5 (AnxA5) suffer from a severe defect in membrane resealing. This defect is rescued by the addition of recombinant AnxA5 while an AnxA5 mutant, which is unable to form 2D protein arrays, has no effect. Using correlative light and electron microscopy, we show that AnxA5 binds to the edges of the torn membrane, as early as a few seconds after sarcolemma injury, where it probably self-assembles into 2D arrays. In addition, we observed that membrane resealing is associated with the presence of a cluster of lipid vesicles at the wounded site. AnxA5 is present at the surface of these vesicles and may thus participate in plugging the cell membrane disruption. Finally, we show that AnxA5 behaves similarly in myotubes from a muscle cell line established from a patient suffering from LGMD2B, a myopathy due to dysferlin mutations, which indicates that trafficking of AnxA5 during sarcolemma damage is independent of the presence of dysferlin.
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19
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Bargiela A, Cerro-Herreros E, Fernandez-Costa JM, Vilchez JJ, Llamusi B, Artero R. Increased autophagy and apoptosis contribute to muscle atrophy in a myotonic dystrophy type 1 Drosophila model. Dis Model Mech 2016; 8:679-90. [PMID: 26092529 PMCID: PMC4486854 DOI: 10.1242/dmm.018127] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Muscle mass wasting is one of the most debilitating symptoms of myotonic dystrophy type 1 (DM1) disease, ultimately leading to immobility, respiratory defects, dysarthria, dysphagia and death in advanced stages of the disease. In order to study the molecular mechanisms leading to the degenerative loss of adult muscle tissue in DM1, we generated an inducible Drosophila model of expanded CTG trinucleotide repeat toxicity that resembles an adult-onset form of the disease. Heat-shock induced expression of 480 CUG repeats in adult flies resulted in a reduction in the area of the indirect flight muscles. In these model flies, reduction of muscle area was concomitant with increased apoptosis and autophagy. Inhibition of apoptosis or autophagy mediated by the overexpression of DIAP1, mTOR (also known as Tor) or muscleblind, or by RNA interference (RNAi)-mediated silencing of autophagy regulatory genes, achieved a rescue of the muscle-loss phenotype. In fact, mTOR overexpression rescued muscle size to a size comparable to that in control flies. These results were validated in skeletal muscle biopsies from DM1 patients in which we found downregulated autophagy and apoptosis repressor genes, and also in DM1 myoblasts where we found increased autophagy. These findings provide new insights into the signaling pathways involved in DM1 disease pathogenesis.
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Affiliation(s)
- Ariadna Bargiela
- Translational Genomics Group, Department of Genetics, University of Valencia, Burjassot 46100, Spain INCLIVA Health Research Institute, Valencia 46010, Spain
| | - Estefanía Cerro-Herreros
- Translational Genomics Group, Department of Genetics, University of Valencia, Burjassot 46100, Spain INCLIVA Health Research Institute, Valencia 46010, Spain
| | - Juan M Fernandez-Costa
- Translational Genomics Group, Department of Genetics, University of Valencia, Burjassot 46100, Spain
| | - Juan J Vilchez
- Neurology Section, Hospital Universitari La Fe, Valencia 46026, Spain Department of Internal Medicine, University of Valencia, Valencia 46010, Spain Centro de Investigaciones Biomedicas en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Institute Carlos III, Ministry of Economy and Competitiveness, Madrid 28049, Spain
| | | | - Ruben Artero
- Translational Genomics Group, Department of Genetics, University of Valencia, Burjassot 46100, Spain INCLIVA Health Research Institute, Valencia 46010, Spain
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20
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Chacon-Cabrera A, Fermoselle C, Salmela I, Yelamos J, Barreiro E. MicroRNA expression and protein acetylation pattern in respiratory and limb muscles of Parp-1−/− and Parp-2−/− mice with lung cancer cachexia. Biochim Biophys Acta Gen Subj 2015; 1850:2530-43. [DOI: 10.1016/j.bbagen.2015.09.020] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 09/09/2015] [Accepted: 09/29/2015] [Indexed: 12/20/2022]
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21
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Barreiro E, Puig-Vilanova E, Marin-Corral J, Chacón-Cabrera A, Salazar-Degracia A, Mateu X, Puente-Maestu L, García-Arumí E, Andreu AL, Molina L. Therapeutic Approaches in Mitochondrial Dysfunction, Proteolysis, and Structural Alterations of Diaphragm and Gastrocnemius in Rats With Chronic Heart Failure. J Cell Physiol 2015; 231:1495-513. [DOI: 10.1002/jcp.25241] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 11/03/2015] [Indexed: 11/09/2022]
Affiliation(s)
- Esther Barreiro
- Department of Pulmonology-Muscle and Respiratory System Research Unit (URMAR), IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS); Universitat Pompeu Fabra (UPF), Barcelona Biomedical Research Park (PRBB); Barcelona Spain
- Centro de Investigación en Red de Enfermedades Respiratorias (CIBERES); Instituto de Salud Carlos III (ISCIII); Barcelona Spain
| | - Ester Puig-Vilanova
- Department of Pulmonology-Muscle and Respiratory System Research Unit (URMAR), IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS); Universitat Pompeu Fabra (UPF), Barcelona Biomedical Research Park (PRBB); Barcelona Spain
| | - Judith Marin-Corral
- Department of Pulmonology-Muscle and Respiratory System Research Unit (URMAR), IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS); Universitat Pompeu Fabra (UPF), Barcelona Biomedical Research Park (PRBB); Barcelona Spain
| | - Alba Chacón-Cabrera
- Department of Pulmonology-Muscle and Respiratory System Research Unit (URMAR), IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS); Universitat Pompeu Fabra (UPF), Barcelona Biomedical Research Park (PRBB); Barcelona Spain
- Centro de Investigación en Red de Enfermedades Respiratorias (CIBERES); Instituto de Salud Carlos III (ISCIII); Barcelona Spain
| | - Anna Salazar-Degracia
- Department of Pulmonology-Muscle and Respiratory System Research Unit (URMAR), IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS); Universitat Pompeu Fabra (UPF), Barcelona Biomedical Research Park (PRBB); Barcelona Spain
- Centro de Investigación en Red de Enfermedades Respiratorias (CIBERES); Instituto de Salud Carlos III (ISCIII); Barcelona Spain
| | - Xavier Mateu
- Servicio de Neumología, Hospital General Gregorio Marañón; Universidad Complutense de Madrid; Madrid Spain
| | - Luis Puente-Maestu
- Servicio de Neumología, Hospital General Gregorio Marañón; Universidad Complutense de Madrid; Madrid Spain
| | - Elena García-Arumí
- Unitat de Patologia Neuromuscular i Mitocondrial, Hospital Universitari Vall d'Hebron Institut de Recerca (VHIR); Universitat Autònoma de Barcelona; Barcelona Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); ISCIII; Barcelona Spain
| | - Antoni L. Andreu
- Unitat de Patologia Neuromuscular i Mitocondrial, Hospital Universitari Vall d'Hebron Institut de Recerca (VHIR); Universitat Autònoma de Barcelona; Barcelona Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER); ISCIII; Barcelona Spain
| | - Luis Molina
- Department of Cardiology, Hospital del Mar, Heart Diseases Biomedical Research Group, IMIM, and Department of Medicine; Universitat Autònoma de Barcelona; Barcelona Spain
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22
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Mateos-Aierdi AJ, Goicoechea M, Aiastui A, Fernández-Torrón R, Garcia-Puga M, Matheu A, López de Munain A. Muscle wasting in myotonic dystrophies: a model of premature aging. Front Aging Neurosci 2015. [PMID: 26217220 PMCID: PMC4496580 DOI: 10.3389/fnagi.2015.00125] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Myotonic dystrophy type 1 (DM1 or Steinert’s disease) and type 2 (DM2) are multisystem disorders of genetic origin. Progressive muscular weakness, atrophy and myotonia are the most prominent neuromuscular features of these diseases, while other clinical manifestations such as cardiomyopathy, insulin resistance and cataracts are also common. From a clinical perspective, most DM symptoms are interpreted as a result of an accelerated aging (cataracts, muscular weakness and atrophy, cognitive decline, metabolic dysfunction, etc.), including an increased risk of developing tumors. From this point of view, DM1 could be described as a progeroid syndrome since a notable age-dependent dysfunction of all systems occurs. The underlying molecular disorder in DM1 consists of the existence of a pathological (CTG) triplet expansion in the 3′ untranslated region (UTR) of the Dystrophia Myotonica Protein Kinase (DMPK) gene, whereas (CCTG)n repeats in the first intron of the Cellular Nucleic acid Binding Protein/Zinc Finger Protein 9(CNBP/ZNF9) gene cause DM2. The expansions are transcribed into (CUG)n and (CCUG)n-containing RNA, respectively, which form secondary structures and sequester RNA-binding proteins, such as the splicing factor muscleblind-like protein (MBNL), forming nuclear aggregates known as foci. Other splicing factors, such as CUGBP, are also disrupted, leading to a spliceopathy of a large number of downstream genes linked to the clinical features of these diseases. Skeletal muscle regeneration relies on muscle progenitor cells, known as satellite cells, which are activated after muscle damage, and which proliferate and differentiate to muscle cells, thus regenerating the damaged tissue. Satellite cell dysfunction seems to be a common feature of both age-dependent muscle degeneration (sarcopenia) and muscle wasting in DM and other muscle degenerative diseases. This review aims to describe the cellular, molecular and macrostructural processes involved in the muscular degeneration seen in DM patients, highlighting the similarities found with muscle aging.
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Affiliation(s)
- Alba Judith Mateos-Aierdi
- Neuroscience Area, Biodonostia Health Research Institute San Sebastián, Spain ; CIBERNED, Instituto Carlos III, Ministerio de Economía y Competitividad Madrid, Spain
| | - Maria Goicoechea
- Neuroscience Area, Biodonostia Health Research Institute San Sebastián, Spain ; CIBERNED, Instituto Carlos III, Ministerio de Economía y Competitividad Madrid, Spain
| | - Ana Aiastui
- CIBERNED, Instituto Carlos III, Ministerio de Economía y Competitividad Madrid, Spain ; Cell Culture Platform, Biodonostia Health Research Institute, San Sebastián Spain
| | - Roberto Fernández-Torrón
- Neuroscience Area, Biodonostia Health Research Institute San Sebastián, Spain ; CIBERNED, Instituto Carlos III, Ministerio de Economía y Competitividad Madrid, Spain ; Department of Neurology, Hospital Universitario Donostia, San Sebastián Spain
| | - Mikel Garcia-Puga
- Oncology Area, Biodonostia Health Research Institute San Sebastián, Spain
| | - Ander Matheu
- Oncology Area, Biodonostia Health Research Institute San Sebastián, Spain
| | - Adolfo López de Munain
- Neuroscience Area, Biodonostia Health Research Institute San Sebastián, Spain ; CIBERNED, Instituto Carlos III, Ministerio de Economía y Competitividad Madrid, Spain ; Department of Neurology, Hospital Universitario Donostia, San Sebastián Spain ; Department of Neuroscience, Universidad del País Vasco UPV-EHU San Sebastián, Spain
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23
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Witherspoon L, O'Reilly S, Hadwen J, Tasnim N, MacKenzie A, Farooq F. Sodium Channel Inhibitors Reduce DMPK mRNA and Protein. Clin Transl Sci 2015; 8:298-304. [PMID: 26011798 DOI: 10.1111/cts.12275] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Myotonic dystrophy type 1 (DM1) is caused by an expanded trinucleotide (CTG)n tract in the 3' untranslated region (UTR) of the dystrophia myotonica protein kinase (DMPK) gene. This results in the aggregation of an expanded mRNA forming toxic intranuclear foci which sequester splicing factors. We believe down-regulation of DMPK mRNA represents a potential, and as yet unexplored, DM1 therapeutic avenue. Consequently, a computational screen for agents which down-regulate DMPK mRNA was undertaken, unexpectedly identifying the sodium channel blockers mexiletine, prilocaine, procainamide, and sparteine as effective suppressors of DMPK mRNA. Analysis of DMPK mRNA in C2C12 myoblasts following treatment with these agents revealed a reduction in the mRNA levels. In vivo analysis of CD1 mice also showed DMPK mRNA and protein down-regulation. The role of DMPK mRNA suppression in the documented efficacy of this class of compounds in DM1 is worthy of further investigation.
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Affiliation(s)
- Luke Witherspoon
- University of Ottawa, Ottawa, Canada.,Apoptosis Research Center, CHEO Research Institute, CHEO, Ottawa, Canada
| | - Sean O'Reilly
- University of Ottawa, Ottawa, Canada.,Apoptosis Research Center, CHEO Research Institute, CHEO, Ottawa, Canada
| | - Jeremiah Hadwen
- University of Ottawa, Ottawa, Canada.,Apoptosis Research Center, CHEO Research Institute, CHEO, Ottawa, Canada
| | - Nafisa Tasnim
- University of Ottawa, Ottawa, Canada.,Apoptosis Research Center, CHEO Research Institute, CHEO, Ottawa, Canada
| | - Alex MacKenzie
- University of Ottawa, Ottawa, Canada.,Apoptosis Research Center, CHEO Research Institute, CHEO, Ottawa, Canada
| | - Faraz Farooq
- Apoptosis Research Center, CHEO Research Institute, CHEO, Ottawa, Canada.,Emirates College for Advance Education, Abu Dhabi, UAE
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24
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Chacon-Cabrera A, Fermoselle C, Urtreger AJ, Mateu-Jimenez M, Diament MJ, de Kier Joffé EDB, Sandri M, Barreiro E. Pharmacological strategies in lung cancer-induced cachexia: effects on muscle proteolysis, autophagy, structure, and weakness. J Cell Physiol 2014; 229:1660-72. [PMID: 24615622 DOI: 10.1002/jcp.24611] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 03/06/2014] [Indexed: 12/13/2022]
Abstract
Cachexia is a relevant comorbid condition of chronic diseases including cancer. Inflammation, oxidative stress, autophagy, ubiquitin-proteasome system, nuclear factor (NF)-κB, and mitogen-activated protein kinases (MAPK) are involved in the pathophysiology of cancer cachexia. Currently available treatment is limited and data demonstrating effectiveness in in vivo models are lacking. Our objectives were to explore in respiratory and limb muscles of lung cancer (LC) cachectic mice whether proteasome, NF-κB, and MAPK inhibitors improve muscle mass and function loss through several molecular mechanisms. Body and muscle weights, limb muscle force, protein degradation and the ubiquitin-proteasome system, signaling pathways, oxidative stress and inflammation, autophagy, contractile and functional proteins, myostatin and myogenin, and muscle structure were evaluated in the diaphragm and gastrocnemius of LC (LP07 adenocarcinoma) bearing cachectic mice (BALB/c), with and without concomitant treatment with NF-κB (sulfasalazine), MAPK (U0126), and proteasome (bortezomib) inhibitors. Compared to control animals, in both respiratory and limb muscles of LC cachectic mice: muscle proteolysis, ubiquitinated proteins, autophagy, myostatin, protein oxidation, FoxO-1, NF-κB and MAPK signaling pathways, and muscle abnormalities were increased, while myosin, creatine kinase, myogenin, and slow- and fast-twitch muscle fiber size were decreased. Pharmacological inhibition of NF-κB and MAPK, but not the proteasome system, induced in cancer cachectic animals, a substantial restoration of muscle mass and force through a decrease in muscle protein oxidation and catabolism, myostatin, and autophagy, together with a greater content of myogenin, and contractile and functional proteins. Attenuation of MAPK and NF-κB signaling pathway effects on muscles is beneficial in cancer-induced cachexia.
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Affiliation(s)
- Alba Chacon-Cabrera
- Pulmonology-Lung Cancer Research Group, IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS), Universitat Pompeu Fabra (UPF), Parc de Recerca Biomèdica de Barcelona (PRBB), Barcelona, Spain; Centro de Investigación en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III (ISCIII), Madrid, Spain
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25
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Meola G, Cardani R. Myotonic dystrophies: An update on clinical aspects, genetic, pathology, and molecular pathomechanisms. Biochim Biophys Acta Mol Basis Dis 2014; 1852:594-606. [PMID: 24882752 DOI: 10.1016/j.bbadis.2014.05.019] [Citation(s) in RCA: 213] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 05/19/2014] [Accepted: 05/20/2014] [Indexed: 01/18/2023]
Abstract
Myotonic dystrophy (DM) is the most common adult muscular dystrophy, characterized by autosomal dominant progressive myopathy, myotonia and multiorgan involvement. To date two distinct forms caused by similar mutations have been identified. Myotonic dystrophy type 1 (DM1, Steinert's disease) is caused by a (CTG)n expansion in DMPK, while myotonic dystrophy type 2 (DM2) is caused by a (CCTG)n expansion in ZNF9/CNBP. When transcribed into CUG/CCUG-containing RNA, mutant transcripts aggregate as nuclear foci that sequester RNA-binding proteins, resulting in spliceopathy of downstream effector genes. However, it is now clear that additional pathogenic mechanism like changes in gene expression, protein translation and micro-RNA metabolism may also contribute to disease pathology. Despite clinical and genetic similarities, DM1 and DM2 are distinct disorders requiring different diagnostic and management strategies. This review is an update on the recent advances in the understanding of the molecular mechanisms behind myotonic dystrophies. This article is part of a Special Issue entitled: Neuromuscular Diseases: Pathology and Molecular Pathogenesis.
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Affiliation(s)
- Giovanni Meola
- Department of Neurology, IRCCS Policlinico San Donato, University of Milan, San Donato Milanese, Milan, Italy; Laboratory of Muscle Histopathology and Molecular Biology, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy.
| | - Rosanna Cardani
- Laboratory of Muscle Histopathology and Molecular Biology, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy.
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26
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Decostre V, Vignaud A, Matot B, Huguet A, Ledoux I, Bertil E, Gjata B, Carlier PG, Gourdon G, Hogrel JY. Longitudinal in vivo muscle function analysis of the DMSXL mouse model of myotonic dystrophy type 1. Neuromuscul Disord 2013; 23:1016-25. [PMID: 24139022 DOI: 10.1016/j.nmd.2013.07.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 07/11/2013] [Accepted: 07/22/2013] [Indexed: 11/27/2022]
Abstract
Myotonic dystrophy is the most common adult muscle dystrophy. In view of emerging therapies, which use animal models as a proof of principle, the development of reliable outcome measures for in vivo longitudinal study of mouse skeletal muscle function is becoming crucial. To satisfy this need, we have developed a device to measure ankle dorsi- and plantarflexion torque in rodents. We present an in vivo 8-month longitudinal study of the contractile properties of the skeletal muscles of the DMSXL mouse model of myotonic dystrophy type 1. Between 4 and 12 months of age, we observed a reduction in muscle strength in the ankle dorsi- and plantarflexors of DMSXL compared to control mice although the strength per muscle cross-section was normal. Mild steady myotonia but no abnormal muscle fatigue was also observed in the DMSXL mice. Magnetic resonance imaging and histological analysis performed at the end of the study showed respectively reduced muscle cross-section area and smaller muscle fibre diameter in DMSXL mice. In conclusion, our study demonstrates the feasibility of carrying out longitudinal in vivo studies of muscle function over several months in a mouse model of myotonic dystrophy confirming the feasibility of this method to test preclinical therapeutics.
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Affiliation(s)
- Valérie Decostre
- Institut de Myologie, UPMC Univ. Paris 6 UM76, Inserm U974, CNRS UMR7215, F-75651 Paris Cedex 13, France.
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27
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Molecular mechanisms of muscle atrophy in myotonic dystrophies. Int J Biochem Cell Biol 2013; 45:2280-7. [PMID: 23796888 DOI: 10.1016/j.biocel.2013.06.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 06/11/2013] [Accepted: 06/12/2013] [Indexed: 02/01/2023]
Abstract
Myotonic dystrophy type 1 (DM1) and myotonic dystrophy type 2 (DM2) are multisystemic diseases that primarily affect skeletal muscle, causing myotonia, muscle atrophy, and muscle weakness. DM1 and DM2 pathologies are caused by expansion of CTG and CCTG repeats in non-coding regions of the genes encoding myotonic dystrophy protein kinase (DMPK) and zinc finger protein 9 (ZNF9) respectively. These expansions cause DM pathologies through accumulation of mutant RNAs that alter RNA metabolism in patients' tissues by targeting RNA-binding proteins such as CUG-binding protein 1 (CUGBP1) and Muscle blind-like protein 1 (MBNL1). Despite overwhelming evidence showing the critical role of RNA-binding proteins in DM1 and DM2 pathologies, the downstream pathways by which these RNA-binding proteins cause muscle wasting and muscle weakness are not well understood. This review discusses the molecular pathways by which DM1 and DM2 mutations might cause muscle atrophy and describes progress toward the development of therapeutic interventions for muscle wasting and weakness in DM1 and DM2. This article is part of a Directed Issue entitled: Molecular basis of muscle wasting.
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28
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Huguet A, Medja F, Nicole A, Vignaud A, Guiraud-Dogan C, Ferry A, Decostre V, Hogrel JY, Metzger F, Hoeflich A, Baraibar M, Gomes-Pereira M, Puymirat J, Bassez G, Furling D, Munnich A, Gourdon G. Molecular, physiological, and motor performance defects in DMSXL mice carrying >1,000 CTG repeats from the human DM1 locus. PLoS Genet 2012; 8:e1003043. [PMID: 23209425 PMCID: PMC3510028 DOI: 10.1371/journal.pgen.1003043] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 09/05/2012] [Indexed: 11/22/2022] Open
Abstract
Myotonic dystrophy type 1 (DM1) is caused by an unstable CTG repeat expansion in the 3′UTR of the DM protein kinase (DMPK) gene. DMPK transcripts carrying CUG expansions form nuclear foci and affect splicing regulation of various RNA transcripts. Furthermore, bidirectional transcription over the DMPK gene and non-conventional RNA translation of repeated transcripts have been described in DM1. It is clear now that this disease may involve multiple pathogenic pathways including changes in gene expression, RNA stability and splicing regulation, protein translation, and micro–RNA metabolism. We previously generated transgenic mice with 45-kb of the DM1 locus and >300 CTG repeats (DM300 mice). After successive breeding and a high level of CTG repeat instability, we obtained transgenic mice carrying >1,000 CTG (DMSXL mice). Here we described for the first time the expression pattern of the DMPK sense transcripts in DMSXL and human tissues. Interestingly, we also demonstrate that DMPK antisense transcripts are expressed in various DMSXL and human tissues, and that both sense and antisense transcripts accumulate in independent nuclear foci that do not co-localize together. Molecular features of DM1-associated RNA toxicity in DMSXL mice (such as foci accumulation and mild missplicing), were associated with high mortality, growth retardation, and muscle defects (abnormal histopathology, reduced muscle strength, and lower motor performances). We have found that lower levels of IGFBP-3 may contribute to DMSXL growth retardation, while increased proteasome activity may affect muscle function. These data demonstrate that the human DM1 locus carrying very large expansions induced a variety of molecular and physiological defects in transgenic mice, reflecting DM1 to a certain extent. As a result, DMSXL mice provide an animal tool to decipher various aspects of the disease mechanisms. In addition, these mice can be used to test the preclinical impact of systemic therapeutic strategies on molecular and physiological phenotypes. Myotonic dystrophy type 1 (DM1) is caused by the abnormal expansion of a CTG repeat located in the DM protein kinase (DMPK) gene. DMPK transcripts carrying CUG expansions form toxic nuclear foci that affect other RNAs. DM1 involve multiple pathogenic pathways including changes in gene expression, RNA stability and splicing regulation, protein translation, and micro–RNA metabolism. We previously generated transgenic mice carrying the human DM1 locus and very large expansions >1,000 CTG (DMSXL mice). Here we described for the first time, the expression pattern of the DMPK sense transcripts in DMSXL and human tissues. We also demonstrate that DMPK antisense transcripts are expressed in various tissues from DMSXL mice and human. Both sense and antisense transcripts form nuclear foci. DMSXL mice showed molecular DM1 features such as foci and mild splicing defects as well as muscles defects, reduced muscle strength, and lower motor performances. These mice recapitulate some molecular features of DM1 leading to physiological abnormalities. DMSXL are not only a tool to decipher various mechanisms involved in DM1 but also to test the preclinical impact of systemic therapeutic strategies.
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Affiliation(s)
- Aline Huguet
- Inserm U781, Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Hôpital Necker-Enfants Malades, Paris, France
| | - Fadia Medja
- Institut de Myologie, Université Paris 6 UMR S974, Inserm U974, CNRS UMR 7215, GH Pitié-Salpêtrière, Paris, France
| | - Annie Nicole
- Inserm U781, Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Hôpital Necker-Enfants Malades, Paris, France
| | - Alban Vignaud
- Institut de Myologie, Université Paris 6 UMR S974, Inserm U974, CNRS UMR 7215, GH Pitié-Salpêtrière, Paris, France
- Généthon, Evry, France
| | - Céline Guiraud-Dogan
- Inserm U955, Département de Neurosciences, Faculté de Médecine, Université Paris XII, Créteil, France
| | - Arnaud Ferry
- Institut de Myologie, Université Paris 6 UMR S974, Inserm U974, CNRS UMR 7215, GH Pitié-Salpêtrière, Paris, France
- Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | - Valérie Decostre
- Institut de Myologie, Université Paris 6 UMR S974, Inserm U974, CNRS UMR 7215, GH Pitié-Salpêtrière, Paris, France
| | - Jean-Yves Hogrel
- Institut de Myologie, Université Paris 6 UMR S974, Inserm U974, CNRS UMR 7215, GH Pitié-Salpêtrière, Paris, France
| | - Friedrich Metzger
- F. Hoffmann-La Roche, CNS Pharma Research and Development, Basel, Switzerland
| | - Andreas Hoeflich
- Leibniz-Institute for Farm Animal Biology (FBN), Dummerstorf, Germany
| | - Martin Baraibar
- UPMC Univ Paris 06, UM 76, Institut de Myologie and Inserm, U974 and CNRS, UMR7215, Paris, France
| | - Mário Gomes-Pereira
- Inserm U781, Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Hôpital Necker-Enfants Malades, Paris, France
| | - Jack Puymirat
- Human Genetics Research Unit, Laval University, Québec City, Québec, Canada
| | - Guillaume Bassez
- Inserm U955, Département de Neurosciences, Faculté de Médecine, Université Paris XII, Créteil, France
| | - Denis Furling
- Institut de Myologie, Université Paris 6 UMR S974, Inserm U974, CNRS UMR 7215, GH Pitié-Salpêtrière, Paris, France
| | - Arnold Munnich
- Inserm U781, Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Hôpital Necker-Enfants Malades, Paris, France
| | - Geneviève Gourdon
- Inserm U781, Université Paris Descartes-Sorbonne Paris Cité, Institut Imagine, Hôpital Necker-Enfants Malades, Paris, France
- * E-mail:
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29
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Mamchaoui K, Trollet C, Bigot A, Negroni E, Chaouch S, Wolff A, Kandalla PK, Marie S, Di Santo J, St Guily JL, Muntoni F, Kim J, Philippi S, Spuler S, Levy N, Blumen SC, Voit T, Wright WE, Aamiri A, Butler-Browne G, Mouly V. Immortalized pathological human myoblasts: towards a universal tool for the study of neuromuscular disorders. Skelet Muscle 2011; 1:34. [PMID: 22040608 PMCID: PMC3235972 DOI: 10.1186/2044-5040-1-34] [Citation(s) in RCA: 198] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 11/01/2011] [Indexed: 11/29/2022] Open
Abstract
Background Investigations into both the pathophysiology and therapeutic targets in muscle dystrophies have been hampered by the limited proliferative capacity of human myoblasts. Isolation of reliable and stable immortalized cell lines from patient biopsies is a powerful tool for investigating pathological mechanisms, including those associated with muscle aging, and for developing innovative gene-based, cell-based or pharmacological biotherapies. Methods Using transduction with both telomerase-expressing and cyclin-dependent kinase 4-expressing vectors, we were able to generate a battery of immortalized human muscle stem-cell lines from patients with various neuromuscular disorders. Results The immortalized human cell lines from patients with Duchenne muscular dystrophy, facioscapulohumeral muscular dystrophy, oculopharyngeal muscular dystrophy, congenital muscular dystrophy, and limb-girdle muscular dystrophy type 2B had greatly increased proliferative capacity, and maintained their potential to differentiate both in vitro and in vivo after transplantation into regenerating muscle of immunodeficient mice. Conclusions Dystrophic cellular models are required as a supplement to animal models to assess cellular mechanisms, such as signaling defects, or to perform high-throughput screening for therapeutic molecules. These investigations have been conducted for many years on cells derived from animals, and would greatly benefit from having human cell models with prolonged proliferative capacity. Furthermore, the possibility to assess in vivo the regenerative capacity of these cells extends their potential use. The innovative cellular tools derived from several different neuromuscular diseases as described in this report will allow investigation of the pathophysiology of these disorders and assessment of new therapeutic strategies.
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Affiliation(s)
- Kamel Mamchaoui
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
| | - Capucine Trollet
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
| | - Anne Bigot
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
| | - Elisa Negroni
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
| | - Soraya Chaouch
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
| | - Annie Wolff
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
| | - Prashanth K Kandalla
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
| | - Solenne Marie
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
| | - James Di Santo
- Innate Immunity Unit, INSERM U 668, Institut Pasteur, Paris, France
| | - Jean Lacau St Guily
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France.,Service d'Oto-Rhino-Laryngologie et de Chirurgie Cervico-Faciale, Faculté de Médecine St Antoine, Université Pierre et Marie Curie, Hôpital Tenon, Paris, France
| | - Francesco Muntoni
- The Dubowitz Neuromuscular Centre, Institute of Child Health, University College, London, UK
| | - Jihee Kim
- The Dubowitz Neuromuscular Centre, Institute of Child Health, University College, London, UK
| | - Susanne Philippi
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,Muscle Research Unit, Experimental and Clinical Research Center, Charité University Hospital and Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Simone Spuler
- Muscle Research Unit, Experimental and Clinical Research Center, Charité University Hospital and Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Nicolas Levy
- Faculté de Médecine de Marseille, Université de la Méditerranée, Inserm UMRS 910 Génétique Médicale et Génomique Fonctionnelle, Marseille, France
| | - Sergiu C Blumen
- Department of Neurology, Hillel Yaffe Medical Center, PO Box 169, Hadera, 38100, Israel
| | - Thomas Voit
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
| | - Woodring E Wright
- UT Southwestern Medical Center, Department of Cell Biology, Dallas, TX 75390, USA
| | - Ahmed Aamiri
- Laboratoire LBCM, Departement de Biologie, Faculté des Sciences, Agadir, Maroc
| | - Gillian Butler-Browne
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
| | - Vincent Mouly
- Thérapie des maladies du muscle strié, Institut de Myologie, UM76, UPMC Université Paris 6, Paris, France.,INSERM U974, Paris, France.,CNRS UMR 7215, Paris, France
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30
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Peripheral neuropathy is linked to a severe form of myotonic dystrophy in transgenic mice. J Neuropathol Exp Neurol 2011; 70:678-85. [PMID: 21760538 DOI: 10.1097/nen.0b013e3182260939] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Myotonic dystrophy type 1 (DM1) is a multisystem disorder with a variable phenotype. The involvement of peripheral nerves in DM1 disease is controversial. The DM1 animal model DM300 transgenic mice that carry 350 to 500 CTG repeats express a mild DM1 phenotype but do not exhibit motor or sensory pathology. Here, we investigated the presence or absence of peripheral neuropathy in transgenic mice (DMSXL) that carry more than 1,300 CTG repeats and display a severe form of DM1. Electrophysiologic, histologic, and morphometric methods were used to investigate the structure and function of peripheral nerves. We observed lower compound muscle action potentials recorded from hind limb muscles and slowing of sciatic nerve conduction velocity in DMSXL versus control mice. Morphometric analyses showed an axonopathy and neuronopathy in the DMSXL mice characterized by a decrease in numbers of myelinated motor axons in sciatic nerve and in spinal cord motor neurons. Pathologic alterations in the structure of hind limb neuromuscular junctions were also detected in the DMSXL mice. These results suggest that peripheral neuropathy can be linked to a large CTG expansion and a severe form of DM1.
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31
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Sicot G, Gourdon G, Gomes-Pereira M. Myotonic dystrophy, when simple repeats reveal complex pathogenic entities: new findings and future challenges. Hum Mol Genet 2011; 20:R116-23. [PMID: 21821673 DOI: 10.1093/hmg/ddr343] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Expanded, non-coding RNAs can exhibit a deleterious gain-of-function causing human disease through abnormal interactions with RNA-binding proteins. Myotonic dystrophy (DM), the prototypical example of an RNA-dominant disorder, is mediated by trinucleotide repeat-containing transcripts that deregulate alternative splicing. Spliceopathy has therefore been a major focus of DM research. However, changes in gene expression, protein translation and micro-RNA metabolism may also contribute to disease pathology. The exciting finding of bidirectional transcription and non-conventional RNA translation of trinucleotide repeat sequences points to a new scenario, in which DM is not mediated by one single expanded RNA transcript, but involves multiple pathogenic elements and pathways. The study of the growing number of human diseases associated with toxic repeat-containing transcripts provides important insight into the understanding of the complex pathways of RNA toxicity. This review describes some of the recent advances in the understanding of the molecular mechanisms behind DM and other RNA-dominant disorders.
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Affiliation(s)
- Géraldine Sicot
- INSERM U781, Université Paris Descartes, Hôpital Necker Enfants Malades, 156 rue de Vaugirard, Paris Cedex 15, France
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Klein AF, Gasnier E, Furling D. Gain of RNA function in pathological cases: Focus on myotonic dystrophy. Biochimie 2011; 93:2006-12. [PMID: 21763392 DOI: 10.1016/j.biochi.2011.06.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 06/23/2011] [Indexed: 12/21/2022]
Abstract
Expansion of repeated sequences in non-coding regions of different genes causes a number of inherited diseases including myotonic dystrophies, Huntington disease-like 2, Fragile X tremor/ataxia syndrome and spinocerebellar ataxia 8, 10, 12, 31. Involvement of an RNA gain-of-function mechanism in pathological case has been described and studied in-depth in myotonic dystrophy type 1 (DM1). This inherited neuromuscular disorder is caused by a (CTG)n >50 expansion in the 3' non-coding region of the dystrophia myotonica-protein kinase (DMPK) gene. Expanded CUG transcripts (CUGexp-RNAs) are sequestered in the nucleus within small aggregates and interfere with the regulatory splicing activities of MBNL1 and CELF1 RNA-binding proteins, leading to the misregulation of the alternative splicing of several transcripts. Despite the relevance of aberrant splicing events in this complex pathology, the CUGexp-RNAs trans-dominant effects alter other splicing-independent processes that may also contribute to DM1 pathogenesis. This review will focus on toxic RNA gain-of-function as a pathologic mechanism for DM1 and other repeat expansion disorders.
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Affiliation(s)
- A F Klein
- UPMC Univ Paris 06, UM 76, F-75013 Paris, France
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Gomes-Pereira M, Cooper TA, Gourdon G. Myotonic dystrophy mouse models: towards rational therapy development. Trends Mol Med 2011; 17:506-17. [PMID: 21724467 DOI: 10.1016/j.molmed.2011.05.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 05/04/2011] [Accepted: 05/17/2011] [Indexed: 01/26/2023]
Abstract
DNA repeat expansions can result in the production of toxic RNA. RNA toxicity has been best characterised in the context of myotonic dystrophy. Nearly 20 mouse models have contributed significant and complementary insights into specific aspects of this novel disease mechanism. These models provide a unique resource to test pharmacological, anti-sense, and gene-therapy therapeutic strategies that target specific events of the pathobiological cascade. Further proof-of-principle concept studies and preclinical experiments require critical and thorough analysis of the multiple myotonic dystrophy transgenic lines available. This review provides in-depth assessment of the molecular and phenotypic features of these models and their contribution towards the dissection of disease mechanisms, and compares them with the human condition. More importantly, it provides critical assessment of their suitability and limitations for preclinical testing of emerging therapeutic strategies.
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Affiliation(s)
- Mário Gomes-Pereira
- Inserm U781, Université Paris Descartes, Faculté de Medicine Necker Enfants Malades, Paris, France.
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Anvar SY, 't Hoen PA, Venema A, van der Sluijs B, van Engelen B, Snoeck M, Vissing J, Trollet C, Dickson G, Chartier A, Simonelig M, van Ommen GJB, van der Maarel SM, Raz V. Deregulation of the ubiquitin-proteasome system is the predominant molecular pathology in OPMD animal models and patients. Skelet Muscle 2011; 1:15. [PMID: 21798095 PMCID: PMC3156638 DOI: 10.1186/2044-5040-1-15] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Accepted: 04/04/2011] [Indexed: 01/07/2023] Open
Abstract
Oculopharyngeal muscular dystrophy (OPMD) is a late-onset progressive muscle disorder caused by a poly-alanine expansion mutation in the Poly(A) Binding Protein Nuclear 1 (PABPN1). The molecular mechanisms that regulate disease onset and progression are largely unknown. In order to identify molecular pathways that are consistently associated with OPMD, we performed an integrated high-throughput transcriptome study in affected muscles of OPMD animal models and patients. The ubiquitin-proteasome system (UPS) was found to be the most consistently and significantly OPMD-deregulated pathway across species. We could correlate the association of the UPS OPMD-deregulated genes with stages of disease progression. The expression trend of a subset of these genes is age-associated and therefore, marks the late onset of the disease, and a second group with expression trends relating to disease-progression. We demonstrate a correlation between expression trends and entrapment into PABPN1 insoluble aggregates of OPMD-deregulated E3 ligases. We also show that manipulations of proteasome and immunoproteasome activity specifically affect the accumulation and aggregation of mutant PABPN1. We suggest that the natural decrease in proteasome expression and its activity during muscle aging contributes to the onset of the disease.
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Affiliation(s)
- Seyed Yahya Anvar
- Center for Human and Clinical Genetics, Leiden University Medical Center, P,O, Box 9600, 2300 RC Leiden, the Netherlands
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