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Dabaj I, Ducatez F, Marret S, Bekri S, Tebani A. Neuromuscular disorders in the omics era. Clin Chim Acta 2024; 553:117691. [PMID: 38081447 DOI: 10.1016/j.cca.2023.117691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/30/2023] [Accepted: 12/02/2023] [Indexed: 12/18/2023]
Abstract
Neuromuscular disorders encompass a spectrum of conditions characterized by primary lesions within the peripheral nervous system, which include the anterior horn cell, peripheral nerve, neuromuscular junction, and muscle. In pediatrics, most of these disorders are linked to genetic causes. Despite the considerable progress, the diagnosis of these disorders remains a challenging due to wide clinical presentation, disease heterogeneity and rarity. It is noteworthy that certain neuromuscular disorders, once deemed untreatable, can now be effectively managed through novel therapies. Biomarkers emerge as indispensable tools, serving as objective measures that not only refine diagnostic accuracy but also provide guidance for therapeutic decision-making and the ongoing monitoring of long-term outcomes. Herein a comprehensive review of biomarkers in neuromuscular disorders is provided. We highlight the role of omics-based technologies that further characterize neuromuscular pathophysiology as well as identify potential therapeutic targets to guide treatment strategies.
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Affiliation(s)
- Ivana Dabaj
- Normandie Univ, UNIROUEN, INSERM U1245, Nord/Est/Ile de France Neuromuscular Reference Center CHU Rouen, Department of Neonatalogy, Pediatric Intensive Care, and Neuropediatrics, F-76000 Rouen, France.
| | - Franklin Ducatez
- Normandie Univ, UNIROUEN, INSERM U1245, Nord/Est/Ile de France Neuromuscular Reference Center CHU Rouen, Department of Neonatalogy, Pediatric Intensive Care, and Neuropediatrics, F-76000 Rouen, France
| | - Stéphane Marret
- Normandie Univ, UNIROUEN, INSERM U1245, Nord/Est/Ile de France Neuromuscular Reference Center CHU Rouen, Department of Neonatalogy, Pediatric Intensive Care, and Neuropediatrics, F-76000 Rouen, France
| | - Soumeya Bekri
- Normandie Univ, UNIROUEN, INSERM U1245, CHU Rouen, Department of Metabolic Biochemistry, F-76000 Rouen, France
| | - Abdellah Tebani
- Normandie Univ, UNIROUEN, INSERM U1245, CHU Rouen, Department of Metabolic Biochemistry, F-76000 Rouen, France
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2
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Lapp HS, Freigang M, Hagenacker T, Weiler M, Wurster CD, Günther R. Biomarkers in 5q-associated spinal muscular atrophy-a narrative review. J Neurol 2023; 270:4157-4178. [PMID: 37289324 PMCID: PMC10421827 DOI: 10.1007/s00415-023-11787-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/15/2023] [Accepted: 05/16/2023] [Indexed: 06/09/2023]
Abstract
5q-associated spinal muscular atrophy (SMA) is a rare genetic disease caused by mutations in the SMN1 gene, resulting in a loss of functional SMN protein and consecutive degeneration of motor neurons in the ventral horn. The disease is clinically characterized by proximal paralysis and secondary skeletal muscle atrophy. New disease-modifying drugs driving SMN gene expression have been developed in the past decade and have revolutionized SMA treatment. The rise of treatment options led to a concomitant need of biomarkers for therapeutic guidance and an improved disease monitoring. Intensive efforts have been undertaken to develop suitable markers, and numerous candidate biomarkers for diagnostic, prognostic, and predictive values have been identified. The most promising markers include appliance-based measures such as electrophysiological and imaging-based indices as well as molecular markers including SMN-related proteins and markers of neurodegeneration and skeletal muscle integrity. However, none of the proposed biomarkers have been validated for the clinical routine yet. In this narrative review, we discuss the most promising candidate biomarkers for SMA and expand the discussion by addressing the largely unfolded potential of muscle integrity markers, especially in the context of upcoming muscle-targeting therapies. While the discussed candidate biomarkers hold potential as either diagnostic (e.g., SMN-related biomarkers), prognostic (e.g., markers of neurodegeneration, imaging-based markers), predictive (e.g., electrophysiological markers) or response markers (e.g., muscle integrity markers), no single measure seems to be suitable to cover all biomarker categories. Hence, a combination of different biomarkers and clinical assessments appears to be the most expedient solution at the time.
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Affiliation(s)
- H S Lapp
- Department of Neurology, University Hospital Carl Gustav Carus at TU Dresden, Fetscherstraße 74, 01307, Dresden, Germany
| | - M Freigang
- Department of Neurology, University Hospital Carl Gustav Carus at TU Dresden, Fetscherstraße 74, 01307, Dresden, Germany
| | - T Hagenacker
- Department of Neurology and Center for Translational Neuro- and Behavioral Science (C-TNBS), University Medicine Essen, Essen, Germany
| | - M Weiler
- Department of Neurology, Heidelberg University Hospital, Heidelberg, Germany
| | - C D Wurster
- Department of Neurology, University Hospital Ulm, Ulm, Germany
- German Center for Neurodegenerative Diseases (DZNE) Ulm, Ulm, Germany
| | - René Günther
- Department of Neurology, University Hospital Carl Gustav Carus at TU Dresden, Fetscherstraße 74, 01307, Dresden, Germany.
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Dresden, Germany.
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3
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Babić M, Banović M, Berečić I, Banić T, Babić Leko M, Ulamec M, Junaković A, Kopić J, Sertić J, Barišić N, Šimić G. Molecular Biomarkers for the Diagnosis, Prognosis, and Pharmacodynamics of Spinal Muscular Atrophy. J Clin Med 2023; 12:5060. [PMID: 37568462 PMCID: PMC10419842 DOI: 10.3390/jcm12155060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 07/24/2023] [Accepted: 07/30/2023] [Indexed: 08/13/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a progressive degenerative illness that affects 1 in every 6 to 11,000 live births. This autosomal recessive disorder is caused by homozygous deletion or mutation of the SMN1 gene (survival motor neuron). As a backup, the SMN1 gene has the SMN2 gene, which produces only 10% of the functional SMN protein. Nusinersen and risdiplam, the first FDA-approved medications, act as SMN2 pre-mRNA splicing modifiers and enhance the quantity of SMN protein produced by this gene. The emergence of new therapies for SMA has increased the demand for good prognostic and pharmacodynamic (response) biomarkers in SMA. This article discusses current molecular diagnostic, prognostic, and pharmacodynamic biomarkers that could be assessed in SMA patients' body fluids. Although various proteomic, genetic, and epigenetic biomarkers have been explored in SMA patients, more research is needed to uncover new prognostic and pharmacodynamic biomarkers (or a combination of biomarkers).
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Affiliation(s)
- Marija Babić
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Maria Banović
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Ivana Berečić
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Tea Banić
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Mirjana Babić Leko
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Monika Ulamec
- Department of Pathology, University Clinical Hospital Sestre Milosrdnice Zagreb, 10000 Zagreb, Croatia
- Department of Pathology, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Alisa Junaković
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Janja Kopić
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
| | - Jadranka Sertić
- Department of Medical Chemistry and Biochemistry, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
- Department of Laboratory Diagnostics, University Hospital Centre Zagreb, 10000 Zagreb, Croatia
| | - Nina Barišić
- Department of Pediatrics, University Hospital Centre Zagreb, 10000 Zagreb, Croatia
| | - Goran Šimić
- Department of Neuroscience, Croatian Institute for Brain Research, University of Zagreb School of Medicine, 10000 Zagreb, Croatia
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4
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Nagree MS, Rybova J, Kleynerman A, Ahrenhoerster CJ, Saville JT, Xu T, Bachochin M, McKillop WM, Lawlor MW, Pshezhetsky AV, Isaeva O, Budde MD, Fuller M, Medin JA. Spinal muscular atrophy-like phenotype in a mouse model of acid ceramidase deficiency. Commun Biol 2023; 6:560. [PMID: 37231125 DOI: 10.1038/s42003-023-04932-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/12/2023] [Indexed: 05/27/2023] Open
Abstract
Mutations in ASAH1 have been linked to two allegedly distinct disorders: Farber disease (FD) and spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME). We have previously reported FD-like phenotypes in mice harboring a single amino acid substitution in acid ceramidase (ACDase), P361R, known to be pathogenic in humans (P361R-Farber). Here we describe a mouse model with an SMA-PME-like phenotype (P361R-SMA). P361R-SMA mice live 2-3-times longer than P361R-Farber mice and have different phenotypes including progressive ataxia and bladder dysfunction, which suggests neurological dysfunction. We found profound demyelination, loss of axons, and altered sphingolipid levels in P361R-SMA spinal cords; severe pathology was restricted to the white matter. Our model can serve as a tool to study the pathological effects of ACDase deficiency on the central nervous system and to evaluate potential therapies for SMA-PME.
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Affiliation(s)
- Murtaza S Nagree
- Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, ON, Canada
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Jitka Rybova
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Annie Kleynerman
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | | | - Jennifer T Saville
- Genetics and Molecular Pathology, SA Pathology at Women's and Children's Hospital, and Adelaide Medical School, University of Adelaide, Adelaide, SA, 5006, Australia
| | - TianMeng Xu
- CHU Sainte-Justine, Université de Montréal, Montréal, QC, H3T 1C5, Canada
| | | | - William M McKillop
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Michael W Lawlor
- Department of Pathology and Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | | | - Olena Isaeva
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Matthew D Budde
- Clement J. Zablocki Veteran's Affairs Medical Center, Milwaukee, WI, 53295, USA
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Maria Fuller
- Genetics and Molecular Pathology, SA Pathology at Women's and Children's Hospital, and Adelaide Medical School, University of Adelaide, Adelaide, SA, 5006, Australia
- Adelaide Medical School, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Jeffrey A Medin
- Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, ON, Canada.
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA.
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, 53226, USA.
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5
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Meneri M, Abati E, Gagliardi D, Faravelli I, Parente V, Ratti A, Verde F, Ticozzi N, Comi GP, Ottoboni L, Corti S. Identification of Novel Biomarkers of Spinal Muscular Atrophy and Therapeutic Response by Proteomic and Metabolomic Profiling of Human Biological Fluid Samples. Biomedicines 2023; 11:biomedicines11051254. [PMID: 37238925 DOI: 10.3390/biomedicines11051254] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 04/16/2023] [Accepted: 04/20/2023] [Indexed: 05/28/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a neuromuscular disease resulting from mutations or deletions in SMN1 that lead to progressive death of alpha motor neurons, ultimately leading to severe muscle weakness and atrophy, as well as premature death in the absence of treatment. Recent approval of SMN-increasing medications as SMA therapy has altered the natural course of the disease. Thus, accurate biomarkers are needed to predict SMA severity, prognosis, drug response, and overall treatment efficacy. This article reviews novel non-targeted omics strategies that could become useful clinical tools for patients with SMA. Proteomics and metabolomics can provide insights into molecular events underlying disease progression and treatment response. High-throughput omics data have shown that untreated SMA patients have different profiles than controls. In addition, patients who clinically improved after treatment have a different profile than those who did not. These results provide a glimpse on potential markers that could assist in identifying therapy responders, in tracing the course of the disease, and in predicting its outcome. These studies have been restricted by the limited number of patients, but the approaches are feasible and can unravel severity-specific neuro-proteomic and metabolic SMA signatures.
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Affiliation(s)
- Megi Meneri
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy
- Stroke Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Elena Abati
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Delia Gagliardi
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Irene Faravelli
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Valeria Parente
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Antonia Ratti
- Laboratory of Neuroscience, Department of Neurology, IRCCS Istituto Auxologico Italiano, 20095 Milan, Italy
- Department Medical Biotechnology and Translational Medicine, University of Milan, 20100 Milan, Italy
| | - Federico Verde
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy
- Laboratory of Neuroscience, Department of Neurology, IRCCS Istituto Auxologico Italiano, 20095 Milan, Italy
| | - Nicola Ticozzi
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy
- Laboratory of Neuroscience, Department of Neurology, IRCCS Istituto Auxologico Italiano, 20095 Milan, Italy
| | - Giacomo P Comi
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Linda Ottoboni
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy
| | - Stefania Corti
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), University of Milan, 20122 Milan, Italy
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
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6
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Krosschell KJ, Dunaway Young S, Peterson I, Curry M, Mazzella A, Jarecki J, Cruz R. Clinical and Research Readiness for Spinal Muscular Atrophy: The Time Is Now for Knowledge Translation. Phys Ther 2022; 102:6651754. [PMID: 35904447 DOI: 10.1093/ptj/pzac108] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 03/05/2022] [Accepted: 06/08/2022] [Indexed: 11/12/2022]
Abstract
UNLABELLED Disease-modifying therapies for spinal muscular atrophy (SMA) are rapidly changing the outlook for many individuals by substantially altering the clinical course, phenotypic expression, and functional outcomes. Physical therapists have played critical roles in the effective conduct and execution of clinical trials leading to the approval of these therapies. Given the treatment landscape, educating practicing clinicians to understand best practice is of great importance, and a timely call to action to facilitate knowledge translation from SMA researchers to clinicians is necessary. The SMA Clinical Trial Readiness Program engaged clinical and research centers, identified physical therapy knowledge gaps related to evaluation and outcomes assessment, and provided educational resources, including the development of a SMA Best Practices Clinical Evaluator Toolkit. Toolkit content synthesizes evidence and covers a breadth of issues relevant to practice, including background on SMA and the drug pipeline; therapist roles and responsibilities related to research; clinical and research evaluation; and useful materials and resources for additional education, training, and professional development. Surveys and telephone interviews were conducted with physical therapists managing individuals with SMA to determine their SMA practice experience and educational needs. Their recommendations, along with synthesized SMA research evidence, provided input into toolkit content development and assisted in identifying gaps important to address. Impact was assessed over time via utilization feedback surveys downloaded by clinicians across various settings. Open-ended feedback supported beneficial use of the toolkit for clinicians and researchers working with individuals with SMA. Next steps should include timely dissemination to bring this resource and others into practice in a systematic, efficacious, and engaging manner. As the treatment landscape for SMA evolves, the therapist's role in multidisciplinary care and research is of great importance, and a call to action for the development, implementation, evaluation and reporting of informed knowledge using evidence-based knowledge translation strategies is critical. IMPACT Partnership among patient advocacy groups, industry collaborators, and key opinion leaders/experts can optimize essential resource development to address the knowledge gap for best practices in physical therapy. This partnership model can be replicated for other diseases, providing an efficient way to support clinical trial readiness and target early development of evidence-based content and resources related to both research and best practice clinical evaluation for physical therapist researchers, clinicians, and patients. While identifying knowledge gaps and resource development are initial steps toward change in SMA practice, a rapidly changing rehabilitation outlook warrants a call to action for enhanced efforts aimed at improving rehabilitation evaluation, assessment, and care for this population. It is critical to forge a timely path forward for development, implementation, and sustainability of effective knowledge translation to practice for SMA.
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Affiliation(s)
- Kristin J Krosschell
- Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Sally Dunaway Young
- Department of Neurology, Stanford University School of Medicine, Stanford, California, USA
| | - Ilse Peterson
- Faegre Drinker Biddle and Reath LLP, Washington, DC, USA
| | - Mary Curry
- Cure SMA, Elk Grove Village, Illinois, USA
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Biomarkers of disease progression in adolescents and adults with 5q spinal muscular atrophy: a systematic review and meta-analysis. Neuromuscul Disord 2022; 32:185-194. [DOI: 10.1016/j.nmd.2021.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 12/07/2021] [Accepted: 12/29/2021] [Indexed: 12/14/2022]
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8
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Abiusi E, Infante P, Cagnoli C, Lospinoso Severini L, Pane M, Coratti G, Pera MC, D'Amico A, Diano F, Novelli A, Spartano S, Fiori S, Baranello G, Moroni I, Mora M, Pasanisi MB, Pocino K, Le Pera L, D'Amico D, Travaglini L, Ria F, Bruno C, Locatelli D, Bertini ES, Morandi LO, Mercuri E, Di Marcotullio L, Tiziano FD. SMA-miRs (miR-181a-5p, -324-5p, and -451a) are overexpressed in spinal muscular atrophy skeletal muscle and serum samples. eLife 2021; 10:68054. [PMID: 34542403 PMCID: PMC8486378 DOI: 10.7554/elife.68054] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 09/13/2021] [Indexed: 12/24/2022] Open
Abstract
Background: Spinal muscular atrophy (SMA) is a neuromuscular disorder characterized by the degeneration of the second motor neuron. The phenotype ranges from very severe to very mild forms. All patients have the homozygous loss of the SMN1 gene and a variable number of SMN2 (generally 2–4 copies), inversely related to the severity. The amazing results of the available treatments have made compelling the need of prognostic biomarkers to predict the progression trajectories of patients. Besides the SMN2 products, few other biomarkers have been evaluated so far, including some miRs. Methods: We performed whole miRNome analysis of muscle samples of patients and controls (14 biopsies and 9 cultures). The levels of muscle differentially expressed miRs were evaluated in serum samples (51 patients and 37 controls) and integrated with SMN2 copies, SMN2 full-length transcript levels in blood and age (SMA-score). Results: Over 100 miRs were differentially expressed in SMA muscle; 3 of them (hsa-miR-181a-5p, -324-5p, -451a; SMA-miRs) were significantly upregulated in the serum of patients. The severity predicted by the SMA-score was related to that of the clinical classification at a correlation coefficient of 0.87 (p<10-5). Conclusions: miRNome analyses suggest the primary involvement of skeletal muscle in SMA pathogenesis. The SMA-miRs are likely actively released in the blood flow; their function and target cells require to be elucidated. The accuracy of the SMA-score needs to be verified in replicative studies: if confirmed, its use could be crucial for the routine prognostic assessment, also in presymptomatic patients. Funding: Telethon Italia (grant #GGP12116).
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Affiliation(s)
- Emanuela Abiusi
- Department of Life Sciences and Public Health, Section of Genomic Medicine, Università cattolica del Sacro Cuore, Roma, Italy
| | - Paola Infante
- Center For Life Nano Science@Sapienza, Istituto Italiano di Tecnologia; Department of Molecular Medicine, Università degli Studi di Roma "La Sapienza", Roma, Italy, Roma, Italy
| | - Cinzia Cagnoli
- Clinical and Experimental Epileptology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy, Roma, Italy
| | | | - Marika Pane
- Pediatric Neurology, Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS-Università Cattolica del Sacro Cuore, Rome, Italy.,Centro Clinico Nemo, Fondazione Policlinico Universitario A. Gemelli IRCCS-Università Cattolica del Sacro Cuore, Roma, Italy
| | - Giorgia Coratti
- Centro Clinico Nemo, Fondazione Policlinico Universitario A. Gemelli IRCCS-Università Cattolica del Sacro Cuore, Roma, Italy
| | - Maria Carmela Pera
- Centro Clinico Nemo, Fondazione Policlinico Universitario A. Gemelli IRCCS-Università Cattolica del Sacro Cuore, Roma, Italy
| | - Adele D'Amico
- Unit of Neuromuscular and Neurodegenerative Disorders, Dept. Neurosciences, Bambino Gesu' Children's Hospital IRCCS, Roma, Italy
| | - Federica Diano
- Department of Life Sciences and Public Health, Section of Genomic Medicine, Università cattolica del Sacro Cuore, Roma, Italy
| | - Agnese Novelli
- Department of Life Sciences and Public Health, Section of Genomic Medicine, Università cattolica del Sacro Cuore, Roma, Italy
| | - Serena Spartano
- Department of Life Sciences and Public Health, Section of Genomic Medicine, Università cattolica del Sacro Cuore, Roma, Italy
| | - Stefania Fiori
- Department of Life Sciences and Public Health, Section of Genomic Medicine, Università cattolica del Sacro Cuore, Roma, Italy
| | - Giovanni Baranello
- Department of Pediatric Neuroscience, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Isabella Moroni
- Neuromuscular Diseases and Neuroimmunology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Marina Mora
- Neuromuscular Diseases and Neuroimmunology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Maria Barbara Pasanisi
- Neuromuscular Diseases and Neuroimmunology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Krizia Pocino
- Department of Medical and Surgical Sciences, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Roma, Italy
| | - Loredana Le Pera
- Bioenergetics and Molecular Biotechnologies (IBIOM), CNR-Institute of Biomembranes, Bari, Italy.,CNR-Institute of Molecular Biology and Pathology (IBPM), Rome, Italy
| | - Davide D'Amico
- Amazentis SA, EPFL Innovation Park, Losanne, Switzerland
| | - Lorena Travaglini
- Unit of Neuromuscular and Neurodegenerative Disorders, Dept. Neurosciences, Bambino Gesu' Children's Hospital IRCCS, Roma, Italy
| | - Francesco Ria
- Department of Translational Medicine and Surgery, Section of General Pathology, Università Cattolica del Sacro Cuore, Roma, Italy.,Fondazione Policlinico Universitario A. Gemelli - IRCCS, Rome, Italy
| | - Claudio Bruno
- Center of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genova, Italy
| | - Denise Locatelli
- Clinical and Experimental Epileptology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy, Roma, Italy
| | - Enrico Silvio Bertini
- Unit of Neuromuscular and Neurodegenerative Disorders, Dept. Neurosciences, Bambino Gesu' Children's Hospital IRCCS, Roma, Italy
| | - Lucia Ovidia Morandi
- Neuromuscular Diseases and Neuroimmunology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Eugenio Mercuri
- Pediatric Neurology, Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS-Università Cattolica del Sacro Cuore, Rome, Italy.,Centro Clinico Nemo, Fondazione Policlinico Universitario A. Gemelli IRCCS-Università Cattolica del Sacro Cuore, Roma, Italy
| | - Lucia Di Marcotullio
- Department of Molecular Medicine, Università degli Studi di Roma "La Sapienza", Roma, Italy.,Laboratory affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Department of Molecular Medicine, Sapienza University, Rome, Italy
| | - Francesco Danilo Tiziano
- Department of Life Sciences and Public Health, Section of Genomic Medicine, Università cattolica del Sacro Cuore, Roma, Italy.,Unit of Medical Genetics, Department of Laboratory science and Infectious Diseases, Fondazione Policlinico Universitario IRCCS "A. Gemelli", Rome, Italy
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9
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Pino MG, Rich KA, Kolb SJ. Update on Biomarkers in Spinal Muscular Atrophy. Biomark Insights 2021; 16:11772719211035643. [PMID: 34421296 PMCID: PMC8371741 DOI: 10.1177/11772719211035643] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 07/07/2021] [Indexed: 11/25/2022] Open
Abstract
The availability of disease modifying therapies for spinal muscular atrophy (SMA) has created an urgent need to identify clinically meaningful biomarkers. Biomarkers present a means to measure and evaluate neurological disease across time. Changes in biomarkers provide insight into disease progression and may reveal biologic, physiologic, or pharmacologic phenomena occurring prior to clinical detection. Efforts to identify biomarkers for SMA, a genetic motor neuron disease characterized by motor neuron degeneration and weakness, have culminated in a number of putative molecular and physiologic markers that evaluate biological media (eg, blood and cerebrospinal fluid [CSF]) or nervous system function. Such biomarkers include SMN2 copy number, SMN mRNA and protein levels, neurofilament proteins (NFs), plasma protein analytes, creatine kinase (CK) and creatinine (Crn), and various electrophysiology and imaging measures. SMN2 copy number inversely correlates with disease severity and is the best predictor of clinical outcome in untreated individuals. SMN mRNA and protein are commonly measured in the blood or CSF of patients receiving SMA therapies, particularly those aimed at increasing SMN protein expression, and provide insight into current disease state. NFs have proven to be robust prognostic, disease progression, and pharmacodynamic markers for SMA infants undergoing treatment, but less so for adolescents and adults. Select plasma proteins are altered in SMA individuals and may track response to therapy. CK and Crn from blood correlate with motor function and disease severity status and are useful for predicting which individuals will respond to therapy. Electrophysiology measures comprise the most reliable means for monitoring motor function throughout disease course and are sensitive enough to detect neuromuscular changes before overt clinical manifestation, making them robust predictive and pharmacodynamic biomarkers. Finally, magnetic resonance imaging and muscle ultrasonography are non-invasive techniques for studying muscle structure and physiology and are useful diagnostic tools, but cannot reliably track disease progression. Importantly, biomarkers can provide information about the underlying mechanisms of disease as well as reveal subclinical disease progression, allowing for more appropriate timing and dosing of therapy for individuals with SMA. Recent therapeutic advancements in SMA have shown promising results, though there is still a great need to identify and understand the impact of biomarkers in modulating disease onset and progression.
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Affiliation(s)
- Megan G Pino
- Department of Neurology, The Ohio State
University Wexner Medical Center, Columbus, OH, USA
| | - Kelly A Rich
- Department of Neurology, The Ohio State
University Wexner Medical Center, Columbus, OH, USA
| | - Stephen J Kolb
- Department of Neurology, The Ohio State
University Wexner Medical Center, Columbus, OH, USA
- Department of Biological Chemistry and
Pharmacology, The Ohio State University Wexner Medical Center, Columbus, OH,
USA
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10
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SMN-deficiency disrupts SERCA2 expression and intracellular Ca 2+ signaling in cardiomyocytes from SMA mice and patient-derived iPSCs. Skelet Muscle 2020; 10:16. [PMID: 32384912 PMCID: PMC7206821 DOI: 10.1186/s13395-020-00232-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 04/22/2020] [Indexed: 11/17/2022] Open
Abstract
Spinal muscular atrophy (SMA) is a neurodegenerative disease characterized by loss of alpha motor neurons and skeletal muscle atrophy. The disease is caused by mutations of the SMN1 gene that result in reduced functional expression of survival motor neuron (SMN) protein. SMN is ubiquitously expressed, and there have been reports of cardiovascular dysfunction in the most severe SMA patients and animal models of the disease. In this study, we directly assessed the function of cardiomyocytes isolated from a severe SMA model mouse and cardiomyocytes generated from patient-derived IPSCs. Consistent with impaired cardiovascular function at the very early disease stages in mice, heart failure markers such as brain natriuretic peptide were significantly elevated. Functionally, cardiomyocyte relaxation kinetics were markedly slowed and the T50 for Ca2+ sequestration increased to 146 ± 4 ms in SMN-deficient cardiomyocytes from 126 ± 4 ms in wild type cells. Reducing SMN levels in cardiomyocytes from control patient IPSCs slowed calcium reuptake similar to SMA patent-derived cardiac cells. Importantly, restoring SMN increased calcium reuptake rate. Taken together, these results indicate that SMN deficiency impairs cardiomyocyte function at least partially through intracellular Ca2+ cycling dysregulation.
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11
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Wirth B, Karakaya M, Kye MJ, Mendoza-Ferreira N. Twenty-Five Years of Spinal Muscular Atrophy Research: From Phenotype to Genotype to Therapy, and What Comes Next. Annu Rev Genomics Hum Genet 2020; 21:231-261. [PMID: 32004094 DOI: 10.1146/annurev-genom-102319-103602] [Citation(s) in RCA: 117] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Twenty-five years ago, the underlying genetic cause for one of the most common and devastating inherited diseases in humans, spinal muscular atrophy (SMA), was identified. Homozygous deletions or, rarely, subtle mutations of SMN1 cause SMA, and the copy number of the nearly identical copy gene SMN2 inversely correlates with disease severity. SMA has become a paradigm and a prime example of a monogenic neurological disorder that can be efficiently ameliorated or nearly cured by novel therapeutic strategies, such as antisense oligonucleotide or gene replacement therapy. These therapies enable infants to survive who might otherwise have died before the age of two and allow individuals who have never been able to sit or walk to do both. The major milestones on the road to these therapies were to understand the genetic cause and splice regulation of SMN genes, the disease's phenotype-genotype variability, the function of the protein and the main affected cellular pathways and tissues, the disease's pathophysiology through research on animal models, the windows of opportunity for efficient treatment, and how and when to treat patients most effectively.This review aims to bridge our knowledge from phenotype to genotype to therapy, not only highlighting the significant advances so far but also speculating about the future of SMA screening and treatment.
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Affiliation(s)
- Brunhilde Wirth
- Institute of Human Genetics, Center for Molecular Medicine Cologne and Center for Rare Diseases, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany;
| | - Mert Karakaya
- Institute of Human Genetics, Center for Molecular Medicine Cologne and Center for Rare Diseases, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany;
| | - Min Jeong Kye
- Institute of Human Genetics, Center for Molecular Medicine Cologne and Center for Rare Diseases, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany;
| | - Natalia Mendoza-Ferreira
- Institute of Human Genetics, Center for Molecular Medicine Cologne and Center for Rare Diseases, University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany;
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12
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Wan B, Feng P, Guan Z, Sheng L, Liu Z, Hua Y. A severe mouse model of spinal muscular atrophy develops early systemic inflammation. Hum Mol Genet 2019; 27:4061-4076. [PMID: 30137324 DOI: 10.1093/hmg/ddy300] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 08/14/2018] [Indexed: 01/17/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a fatal genetic disease, mainly affecting children. A number of recent studies show, aside from lower motor neuron degeneration and atrophy of skeletal muscles, widespread defects present in the central nervous system (CNS) and peripheral non-neuronal cell types of SMA patients and mouse models, particularly of severe forms. However, molecular mechanisms underlying the multi-organ manifestations of SMA were hardly understood. Here, using histology, flow cytometry and gene expression analysis in both messenger RNA and protein levels in various tissues, we found that a severe SMA mouse model develops systemic inflammation in early symptomatic stages. SMA mice had an enhanced intestinal permeability, resulting in microbial invasion into the circulatory system. Expression of proinflammatory cytokines was increased in all tissues and the acute phase response in the liver was activated. Systemic inflammation further mobilized glucocorticoid signaling and in turn led to dysregulation of a large set of genes, including robust upregulation of FAM107A in the spinal cord, increased expression of which has been implicated in neurodegeneration. Moreover, we show that lipopolysaccharide challenge markedly suppressed survival of motor neuron 2 exon 7 splicing in all examined peripheral and CNS tissues, resulting in global survival of motor neuron level reduction. Therefore, we identified a novel pathological mechanism in a severe SMA mouse model, which affects phenotypic severity through multiple paths and should contribute to progression of broad neuronal and non-neuronal defects.
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Affiliation(s)
- Bo Wan
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, Hospital of Soochow University, Suzhou, Jiangsu, China.,Institute of Neuroscience, Soochow University, Suzhou, Jiangsu, China
| | - Pengchao Feng
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, Hospital of Soochow University, Suzhou, Jiangsu, China.,Institute of Neuroscience, Soochow University, Suzhou, Jiangsu, China
| | - Zeyuan Guan
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, Hospital of Soochow University, Suzhou, Jiangsu, China.,Institute of Neuroscience, Soochow University, Suzhou, Jiangsu, China
| | - Lei Sheng
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, Hospital of Soochow University, Suzhou, Jiangsu, China.,Institute of Neuroscience, Soochow University, Suzhou, Jiangsu, China
| | - Zhiyong Liu
- School for Radiological and Interdisciplinary Sciences (RAD-X), Soochow University, Suzhou, Jiangsu, China.,Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou, Jiangsu, China
| | - Yimin Hua
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Neurology and Suzhou Clinical Research Center of Neurological Disease, Hospital of Soochow University, Suzhou, Jiangsu, China.,Institute of Neuroscience, Soochow University, Suzhou, Jiangsu, China
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13
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Tiziano FD, Lomastro R, Abiusi E, Pasanisi MB, Di Pietro L, Fiori S, Baranello G, Angelini C, Sorarù G, Gaiani A, Mongini T, Vercelli L, Mercuri E, Vasco G, Pane M, Vita G, Vita G, Messina S, Petillo R, Passamano L, Politano L, Campanella A, Mantegazza R, Morandi L. Longitudinal evaluation of SMN levels as biomarker for spinal muscular atrophy: results of a phase IIb double-blind study of salbutamol. J Med Genet 2018; 56:293-300. [DOI: 10.1136/jmedgenet-2018-105482] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 11/10/2018] [Accepted: 11/30/2018] [Indexed: 11/04/2022]
Abstract
BackgroundSpinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder, due to the loss of function of the survival motor neuron (SMN1) gene. The first treatment for the condition, recently approved, is based on the reduction of exon 7 skipping in mRNAs produced by a highly homologous gene (SMN2). The primary objective of the present study was to evaluate the applicability of the dosage of SMN gene produts in blood, as biomarker for SMA, and the safety of oral salbutamol, a beta2-adrenergic agonist modulating SMN2 levels.MethodsWe have performed a 1-year multicentre, double-blind, placebo-controlled study with salbutamol in 45 adult patients with SMA. Patients assumed 4 mg of salbutamol or placebo/three times a day. Molecular tests were SMN2 copy number, SMN transcript and protein levels. We have also explored the clinical effect, by the outcome measures available at the time of study design.ResultsThirty-six patients completed the study. Salbutamol was safe and well tolerated. We observed a significant and progressive increase in SMN2 full-length levels in peripheral blood of the salbutamol-treated patients (p<0.00001). The exploratory analysis of motor function showed an improvement in most patients.ConclusionsOur data demonstrate safety and molecular efficacy of salbutamol. We provide the first longitudinal evaluation of SMN levels (both transcripts and protein) in placebo and in response to a compound modulating the gene expression: SMN transcript dosage in peripheral blood is reliable and may be used as pharmacodynamic marker in clinical trials with systemic compounds modifying SMN2levels.Trial registration numberEudraCT no. 2007-001088-32.
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14
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Šoltić D, Bowerman M, Stock J, Shorrock HK, Gillingwater TH, Fuller HR. Multi-Study Proteomic and Bioinformatic Identification of Molecular Overlap between Amyotrophic Lateral Sclerosis (ALS) and Spinal Muscular Atrophy (SMA). Brain Sci 2018; 8:brainsci8120212. [PMID: 30518112 PMCID: PMC6315439 DOI: 10.3390/brainsci8120212] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/28/2018] [Accepted: 11/30/2018] [Indexed: 12/24/2022] Open
Abstract
Unravelling the complex molecular pathways responsible for motor neuron degeneration in amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) remains a persistent challenge. Interest is growing in the potential molecular similarities between these two diseases, with the hope of better understanding disease pathology for the guidance of therapeutic development. The aim of this study was to conduct a comparative analysis of published proteomic studies of ALS and SMA, seeking commonly dysregulated molecules to be prioritized as future therapeutic targets. Fifteen proteins were found to be differentially expressed in two or more proteomic studies of both ALS and SMA, and bioinformatics analysis identified over-representation of proteins known to associate in vesicles and molecular pathways, including metabolism of proteins and vesicle-mediated transport—both of which converge on endoplasmic reticulum (ER)-Golgi trafficking processes. Calreticulin, a calcium-binding chaperone found in the ER, was associated with both pathways and we independently confirm that its expression was decreased in spinal cords from SMA and increased in spinal cords from ALS mice. Together, these findings offer significant insights into potential common targets that may help to guide the development of new therapies for both diseases.
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Affiliation(s)
- Darija Šoltić
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (D.S.); (M.B.)
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10 7AG, UK
| | - Melissa Bowerman
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (D.S.); (M.B.)
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10 7AG, UK
| | - Joanne Stock
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (D.S.); (M.B.)
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10 7AG, UK
| | - Hannah K. Shorrock
- Biomedical Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh EH8 9AG, UK; (H.K.S.); (T.H.G.)
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Thomas H. Gillingwater
- Biomedical Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh EH8 9AG, UK; (H.K.S.); (T.H.G.)
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh EH8 9AG, UK
| | - Heidi R. Fuller
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (D.S.); (M.B.)
- Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10 7AG, UK
- Correspondence: ; Tel.: +44-169-140-4693; Fax: +44-169-140-4065
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15
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Saffari A, Kölker S, Hoffmann GF, Weiler M, Ziegler A. Novel challenges in spinal muscular atrophy - How to screen and whom to treat? Ann Clin Transl Neurol 2018; 6:197-205. [PMID: 30656198 PMCID: PMC6331314 DOI: 10.1002/acn3.689] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 10/17/2018] [Accepted: 10/18/2018] [Indexed: 12/27/2022] Open
Abstract
In recent years, disease‐modifying and life‐prolonging therapies for spinal muscular atrophy (SMA) have been developed. However, patients are currently diagnosed with significant delay and therapies are often administered in advanced stages of motor neuron degeneration, showing limited effects. Methods to identify children in presymptomatic stages are currently evaluated in newborn screening programs. Yet, not all children develop symptoms shortly after birth raising the question whom to treat and when to initiate therapy. Finally, monitoring disease progression becomes essential to individualize management. Here, we review the literature on screening approaches, strategies to predict disease severity, and biomarkers to monitor therapy.
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Affiliation(s)
- Afshin Saffari
- Division of Child Neurology and Metabolic Medicine Center for Child and Adolescent Medicine University Hospital Heidelberg Heidelberg Germany
| | - Stefan Kölker
- Division of Child Neurology and Metabolic Medicine Center for Child and Adolescent Medicine University Hospital Heidelberg Heidelberg Germany
| | - Georg F Hoffmann
- Division of Child Neurology and Metabolic Medicine Center for Child and Adolescent Medicine University Hospital Heidelberg Heidelberg Germany
| | - Markus Weiler
- Department of Neurology University Hospital Heidelberg Heidelberg Germany
| | - Andreas Ziegler
- Division of Child Neurology and Metabolic Medicine Center for Child and Adolescent Medicine University Hospital Heidelberg Heidelberg Germany
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16
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Tizzano EF, Zafeiriou D. Prenatal aspects in spinal muscular atrophy: From early detection to early presymptomatic intervention. Eur J Paediatr Neurol 2018; 22:944-950. [PMID: 30219357 DOI: 10.1016/j.ejpn.2018.08.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 08/23/2018] [Accepted: 08/29/2018] [Indexed: 01/22/2023]
Abstract
With the recent advances in spinal muscular atrophy therapies, the complete scenario of standard of care and following up is changing not only in the clinical field with new phenotypes emerging but also with new expectations for patients, caregivers and health providers. The actual evidence indicates that early intervention and treatment is crucial for better response and prognosis. Knowledge of the prenatal and pre-symptomatic postnatal stages of the disease are becoming essential to consider the opportunities of timely diagnosis and to decide the earliest therapeutic intervention.
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Affiliation(s)
- Eduardo F Tizzano
- Department of Clinical and Molecular Genetics and Rare Diseases Unit and Medicine Genetics Group, VHIR, Hospital Valle Hebron, Barcelona, Spain; CIBERER, Barcelona, Spain.
| | - Dimitrios Zafeiriou
- 1st Department of Pediatrics, "Hippokratio" General Hospital, Aristotle University, Thessaloniki, Greece.
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17
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Evaluation of potential effects of Plastin 3 overexpression and low-dose SMN-antisense oligonucleotides on putative biomarkers in spinal muscular atrophy mice. PLoS One 2018; 13:e0203398. [PMID: 30188931 PMCID: PMC6126849 DOI: 10.1371/journal.pone.0203398] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 08/20/2018] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVES Spinal muscular atrophy (SMA) is a devastating motor neuron disorder caused by homozygous loss of the survival motor neuron 1 (SMN1) gene and insufficient functional SMN protein produced by the SMN2 copy gene. Additional genetic protective modifiers such as Plastin 3 (PLS3) can counteract SMA pathology despite insufficient SMN protein. Recently, Spinraza, an SMN antisense oligonucleotide (ASO) that restores full-length SMN2 transcripts, has been FDA- and EMA-approved for SMA therapy. Hence, the availability of biomarkers allowing a reliable monitoring of disease and therapy progression would be of great importance. Our objectives were (i) to analyse the feasibility of SMN and of six SMA biomarkers identified by the BforSMA study in the Taiwanese SMA mouse model, (ii) to analyse the effect of PLS3 overexpression on these biomarkers, and (iii) to assess the impact of low-dose SMN-ASO therapy on the level of SMN and the six biomarkers. METHODS At P10 and P21, the level of SMN and six putative biomarkers were compared among SMA, heterozygous and wild type mice, with or without PLS3 overexpression, and with or without presymptomatic low-dose SMN-ASO subcutaneous injection. SMN levels were measured in whole blood by ECL immunoassay and of six SMA putative biomarkers, namely Cartilage Oligomeric Matrix Protein (COMP), Dipeptidyl Peptidase 4 (DPP4), Tetranectin (C-type Lectin Family 3 Member B, CLEC3B), Osteopontin (Secreted Phosphoprotein 1, SPP1), Vitronectin (VTN) and Fetuin A (Alpha 2-HS Glycoprotein, AHSG) in plasma. RESULTS SMN levels were significantly discernible between SMA, heterozygous and wild type mice. However, no significant differences were measured upon low-dose SMN-ASO treatment compared to untreated animals. Of the six biomarkers, only COMP and DPP4 showed high and SPP1 moderate correlation with the SMA phenotype. PLS3 overexpression neither influenced the SMN level nor the six biomarkers, supporting the hypothesis that PLS3 acts as an independent protective modifier.
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18
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Chabanon A, Seferian AM, Daron A, Péréon Y, Cances C, Vuillerot C, De Waele L, Cuisset JM, Laugel V, Schara U, Gidaro T, Gilabert S, Hogrel JY, Baudin PY, Carlier P, Fournier E, Lowes LP, Hellbach N, Seabrook T, Toledano E, Annoussamy M, Servais L. Prospective and longitudinal natural history study of patients with Type 2 and 3 spinal muscular atrophy: Baseline data NatHis-SMA study. PLoS One 2018; 13:e0201004. [PMID: 30048507 PMCID: PMC6062049 DOI: 10.1371/journal.pone.0201004] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 07/05/2018] [Indexed: 12/20/2022] Open
Abstract
Spinal muscular atrophy (SMA) is a monogenic disorder caused by loss of function mutations in the survival motor neuron 1 gene, which results in a broad range of disease severity, from neonatal to adult onset. There is currently a concerted effort to define the natural history of the disease and develop outcome measures that accurately capture its complexity. As several therapeutic strategies are currently under investigation and both the FDA and EMA have recently approved the first medical treatment for SMA, there is a critical need to identify the right association of responsive outcome measures and biomarkers for individual patient follow-up. As an approved treatment becomes available, untreated patients will soon become rare, further intensifying the need for a rapid, prospective and longitudinal study of the natural history of SMA Type 2 and 3. Here we present the baseline assessments of 81 patients aged 2 to 30 years of which 19 are non-sitter SMA Type 2, 34 are sitter SMA Type 2, 9 non-ambulant SMA Type 3 and 19 ambulant SMA Type 3. Collecting these data at nine sites in France, Germany and Belgium established the feasibility of gathering consistent data from numerous and demanding assessments in a multicenter SMA study. Most assessments discriminated between the four groups well. This included the Motor Function Measure (MFM), pulmonary function testing, strength, electroneuromyography, muscle imaging and workspace volume. Additionally, all of the assessments showed good correlation with the MFM score. As the untreated patient population decreases, having reliable and valid multi-site data will be imperative for recruitment in clinical trials. The pending two-year study results will evaluate the sensitivity of the studied outcomes and biomarkers to disease progression. Trial Registration: ClinicalTrials.gov (NCT02391831).
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Affiliation(s)
| | | | - Aurore Daron
- Centre de Référence des Maladies Neuromusculaires, CHU de Liège, Belgium
| | - Yann Péréon
- Centre de Référence Maladies Neuromusculaires Atlantique-Occitanie-Caraïbes, Hôpital Hôtel-Dieu, Nantes, France
| | - Claude Cances
- Centre de Référence des Maladies Neuromusculaires, Hôpital des Enfants, Toulouse, France
- Unité de neurologie pédiatrique, Hôpital des Enfants, Toulouse, France
| | - Carole Vuillerot
- Service de rééducation pédiatrique infantile”L’Escale”, Hôpital Mère Enfant, CHU-Lyon, Lyon, France
| | - Liesbeth De Waele
- Department of Pediatric Neurology, University Hospitals Leuven, Leuven, Belgium
- Department of Development and Regeneration, KU Leuven Kulak Kortijk, Kortrijk, Belgium
| | - Jean-Marie Cuisset
- Centre de Référence des Maladies Neuromusculaires, Hôpital Roger Salengro, Lille, France
- Service de Neuropédiatrie, Hôpital Roger Salengro, Lille, France
| | - Vincent Laugel
- Neuropédiatrie/INSERM CIC 1434, CHU Strasbourg Hautepierre, Strasbourg, France
| | - Ulrike Schara
- Paediatric neurology and neuromuscular center, University of Essen, Essen, Germany
| | - Teresa Gidaro
- Institute of Myology, GH Pitié Salpêtrière, Paris, France
| | | | | | - Pierre-Yves Baudin
- Consultants for Research in Imaging and Spectroscopy (CRIS), Tournai, Belgium
| | - Pierre Carlier
- Institute of Myology, GH Pitié Salpêtrière, Paris, France
| | | | - Linda Pax Lowes
- Center for Gene Therapy, Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Nicole Hellbach
- Roche Pharmaceutical Research and Early Development, Roche Innovation Center, Basel, Switzerland
| | - Timothy Seabrook
- Roche Pharmaceutical Research and Early Development, Roche Innovation Center, Basel, Switzerland
| | | | | | - Laurent Servais
- Institute of Myology, GH Pitié Salpêtrière, Paris, France
- Centre de Référence des Maladies Neuromusculaires, CHU de Liège, Belgium
- Service de Pédiatrie, CHU de Liège, Liège, Belgium
- * E-mail:
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19
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Matsumaru N, Hattori R, Ichinomiya T, Tsukamoto K, Kato Z. New quantitative method for evaluation of motor functions applicable to spinal muscular atrophy. Brain Dev 2018; 40:172-180. [PMID: 29395660 DOI: 10.1016/j.braindev.2017.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 11/15/2017] [Accepted: 12/04/2017] [Indexed: 10/18/2022]
Abstract
OBJECTIVE The aim of this study was to develop and introduce new method to quantify motor functions of the upper extremity. METHODS The movement was recorded using a three-dimensional motion capture system, and the movement trajectory was analyzed using newly developed two indices, which measure precise repeatability and directional smoothness. Our target task was shoulder flexion repeated ten times. We applied our method to a healthy adult without and with a weight, simulating muscle impairment. We also applied our method to assess the efficacy of a drug therapy for amelioration of motor functions in a non-ambulatory patient with spinal muscular atrophy. Movement trajectories before and after thyrotropin-releasing hormone therapy were analyzed. RESULTS In the healthy adult, we found the values of both indices increased significantly when holding a weight so that the weight-induced deterioration in motor function was successfully detected. From the efficacy assessment of drug therapy in the patient, the directional smoothness index successfully detected improvements in motor function, which were also clinically observed by the patient's doctors. CONCLUSION We have developed a new quantitative evaluation method of motor functions of the upper extremity. Clinical usability of this method is also greatly enhanced by reducing the required number of body-attached markers to only one. This simple but universal approach to quantify motor functions will provide additional insights into the clinical phenotypes of various neuromuscular diseases and developmental disorders.
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Affiliation(s)
- Naoki Matsumaru
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Japan; Global Regulatory Science, Gifu Pharmaceutical University, Japan.
| | - Ryo Hattori
- Division of Rehabilitation, Gifu University Hospital, Japan
| | - Takashi Ichinomiya
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Japan; Department of Biomedical Informatics, Graduate School of Medicine, Gifu University, Japan
| | | | - Zenichiro Kato
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Japan; Department of Pediatrics, Graduate School of Medicine, Gifu University, Japan
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20
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Bora G, Subaşı-Yıldız Ş, Yeşbek-Kaymaz A, Bulut N, Alemdaroğlu İ, Tunca-Yılmaz Ö, Topaloğlu H, Karaduman AA, Erdem-Yurter H. Effects of Arm Cycling Exercise in Spinal Muscular Atrophy Type II Patients: A Pilot Study. J Child Neurol 2018; 33:209-215. [PMID: 29327642 DOI: 10.1177/0883073817750500] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Exercise studies in neuromuscular diseases like spinal muscular atrophy (SMA), a devastating disease caused by survival of motor neuron 1 ( SMN1) gene mutations, are drawing attention due to its beneficial effects. In this study, we presented a constructed arm cycling exercise protocol and evaluated the benefits on SMA patients. Five SMA type II patients performed 12 weeks of supervised arm cycling exercise. The physical functions were evaluated together with the SMN2 copy numbers, SMN protein levels, insulin-like growth factor 1(IGF1) and binding protein 3 (IGFBP3) levels. The active cycling distance and duration of patients significantly improved. Significant changes could not have detected either SMN or IGF1 and IGFBP3 levels in response to exercise. The findings demonstrated that the patients tolerated the exercise protocol and gained a benefit from arm cycling but benefits could not be associated with SMN2 copy number, SMN protein level, IGF1, or IGFBP3 levels.
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Affiliation(s)
- Gamze Bora
- 1 Faculty of Medicine, Department of Medical Biology, Hacettepe University, Ankara, Turkey
| | - Şulenur Subaşı-Yıldız
- 2 Faculty of Health Sciences, Department of Physical Therapy and Rehabilitation, Hacettepe University, Ankara, Turkey
| | - Ayşe Yeşbek-Kaymaz
- 1 Faculty of Medicine, Department of Medical Biology, Hacettepe University, Ankara, Turkey
| | - Numan Bulut
- 2 Faculty of Health Sciences, Department of Physical Therapy and Rehabilitation, Hacettepe University, Ankara, Turkey
| | - İpek Alemdaroğlu
- 2 Faculty of Health Sciences, Department of Physical Therapy and Rehabilitation, Hacettepe University, Ankara, Turkey
| | - Öznur Tunca-Yılmaz
- 2 Faculty of Health Sciences, Department of Physical Therapy and Rehabilitation, Hacettepe University, Ankara, Turkey
| | - Haluk Topaloğlu
- 3 Faculty of Medicine, Department of Pediatrics, Neurology Unit, Hacettepe University, Ankara, Turkey
| | - Aynur Ayşe Karaduman
- 2 Faculty of Health Sciences, Department of Physical Therapy and Rehabilitation, Hacettepe University, Ankara, Turkey
| | - Hayat Erdem-Yurter
- 1 Faculty of Medicine, Department of Medical Biology, Hacettepe University, Ankara, Turkey
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21
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Alfano LN, Yin H, Dvorchik I, Maus EG, Flanigan KM, Mendell JR, Lowes LP. Modeling functional decline over time in sporadic inclusion body myositis. Muscle Nerve 2016; 55:526-531. [DOI: 10.1002/mus.25373] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 07/26/2016] [Accepted: 08/08/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Lindsay N. Alfano
- The Research Institute at Nationwide Children's Hospital, Center for Gene Therapy, 700 Children's Drive, Room AB1042; Columbus Ohio 43205 USA
| | - Han Yin
- The Research Institute at Nationwide Children's Hospital, Biostatistics Core; Columbus Ohio USA
| | - Igor Dvorchik
- The Research Institute at Nationwide Children's Hospital, Biostatistics Core; Columbus Ohio USA
| | - Elizabeth G. Maus
- The Research Institute at Nationwide Children's Hospital, Center for Gene Therapy, 700 Children's Drive, Room AB1042; Columbus Ohio 43205 USA
| | - Kevin M. Flanigan
- The Research Institute at Nationwide Children's Hospital, Center for Gene Therapy, 700 Children's Drive, Room AB1042; Columbus Ohio 43205 USA
| | - Jerry R. Mendell
- The Research Institute at Nationwide Children's Hospital, Center for Gene Therapy, 700 Children's Drive, Room AB1042; Columbus Ohio 43205 USA
| | - Linda P. Lowes
- The Research Institute at Nationwide Children's Hospital, Center for Gene Therapy, 700 Children's Drive, Room AB1042; Columbus Ohio 43205 USA
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22
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Arnold WD, Duque S, Iyer CC, Zaworski P, McGovern VL, Taylor SJ, von Herrmann KM, Kobayashi DT, Chen KS, Kolb SJ, Paushkin SV, Burghes AHM. Normalization of Patient-Identified Plasma Biomarkers in SMNΔ7 Mice following Postnatal SMN Restoration. PLoS One 2016; 11:e0167077. [PMID: 27907033 PMCID: PMC5132001 DOI: 10.1371/journal.pone.0167077] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 11/08/2016] [Indexed: 12/11/2022] Open
Abstract
INTRODUCTION AND OBJECTIVE Spinal muscular atrophy (SMA) is an autosomal recessive motor neuron disorder. SMA is caused by homozygous loss of the SMN1 gene and retention of the SMN2 gene resulting in reduced levels of full length SMN protein that are insufficient for motor neuron function. Various treatments that restore levels of SMN are currently in clinical trials and biomarkers are needed to determine the response to treatment. Here, we sought to investigate in SMA mice a set of plasma analytes, previously identified in patients with SMA to correlate with motor function. The goal was to determine whether levels of plasma markers were altered in the SMNΔ7 mouse model of SMA and whether postnatal SMN restoration resulted in normalization of the biomarkers. METHODS SMNΔ7 and control mice were treated with antisense oligonucleotides (ASO) targeting ISS-N1 to increase SMN protein from SMN2 or scramble ASO (sham treatment) via intracerebroventricular injection on postnatal day 1 (P1). Brain, spinal cord, quadriceps muscle, and liver were analyzed for SMN protein levels at P12 and P90. Ten plasma biomarkers (a subset of biomarkers in the SMA-MAP panel available for analysis in mice) were analyzed in plasma obtained at P12, P30, and P90. RESULTS Of the eight plasma biomarkers assessed, 5 were significantly changed in sham treated SMNΔ7 mice compared to control mice and were normalized in SMNΔ7 mice treated with ASO. CONCLUSION This study defines a subset of the SMA-MAP plasma biomarker panel that is abnormal in the most commonly used mouse model of SMA. Furthermore, some of these markers are responsive to postnatal SMN restoration. These findings support continued clinical development of these potential prognostic and pharmacodynamic biomarkers.
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MESH Headings
- Animals
- Animals, Newborn
- Biomarkers/metabolism
- Brain/metabolism
- Brain/pathology
- Clinical Trials as Topic
- Disease Models, Animal
- Gene Expression Regulation
- Genetic Complementation Test
- Humans
- Injections, Intraventricular
- Liver/metabolism
- Liver/pathology
- Mice
- Mice, Transgenic
- Motor Neurons/metabolism
- Motor Neurons/pathology
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscular Atrophy, Spinal/genetics
- Muscular Atrophy, Spinal/metabolism
- Muscular Atrophy, Spinal/pathology
- Oligonucleotides, Antisense/genetics
- Oligonucleotides, Antisense/metabolism
- Spinal Cord/metabolism
- Spinal Cord/pathology
- Survival of Motor Neuron 1 Protein/genetics
- Survival of Motor Neuron 1 Protein/metabolism
- Survival of Motor Neuron 2 Protein/genetics
- Survival of Motor Neuron 2 Protein/metabolism
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Affiliation(s)
- W. David Arnold
- Department of Neurology, The Ohio State University Wexner Medical Center, Columbus Ohio, United States of America
- Department of Physical Medicine and Rehabilitation, The Ohio State University Wexner Medical Center, Columbus Ohio, United States of America
| | - Sandra Duque
- VIB Center for the Biology of Disease – KU Leuven Department of Human Genetics, Leuven Belgium, United States of America
| | - Chitra C. Iyer
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, Columbus Ohio, United States of America
| | | | - Vicki L. McGovern
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, Columbus Ohio, United States of America
| | | | | | | | - Karen S. Chen
- SMA Foundation, New York, New York, United States of America
| | - Stephen J. Kolb
- Department of Neurology, The Ohio State University Wexner Medical Center, Columbus Ohio, United States of America
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, Columbus Ohio, United States of America
| | | | - Arthur H. M. Burghes
- Department of Neurology, The Ohio State University Wexner Medical Center, Columbus Ohio, United States of America
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, Columbus Ohio, United States of America
- * E-mail:
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23
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Fuller HR, Gillingwater TH, Wishart TM. Commonality amid diversity: Multi-study proteomic identification of conserved disease mechanisms in spinal muscular atrophy. Neuromuscul Disord 2016; 26:560-9. [PMID: 27460344 DOI: 10.1016/j.nmd.2016.06.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 06/03/2016] [Indexed: 01/09/2023]
Abstract
The neuromuscular disease spinal muscular atrophy (SMA) is a leading genetic cause of infant mortality, resulting from low levels of full-length survival motor neuron (SMN) protein. Despite having a good understanding of the underlying genetics of SMA, the molecular pathways downstream of SMN that regulate disease pathogenesis remain unclear. The identification of molecular perturbations downstream of SMN is required in order to fully understand the fundamental biological role(s) for SMN in cells and tissues of the body, as well as to develop a range of therapeutic targets for developing novel treatments for SMA. Recent developments in proteomic screening technologies have facilitated proteome-wide investigations of a range of SMA models and tissues, generating novel insights into disease mechanisms by highlighting conserved changes in a range of molecular pathways. Comparative analysis of distinct proteomic datasets reveals conserved changes in pathways converging on GAP43, GAPDH, NCAM, UBA1, LMNA, ANXA2 and COL6A3. Proteomic studies therefore represent a leading tool with which to dissect the molecular mechanisms of disease pathogenesis in SMA, serving to identify potentially attractive targets for the development of novel therapies.
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Affiliation(s)
- Heidi R Fuller
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry SY10 7AG, UK; Institute for Science and Technology in Medicine, Keele University, Staffordshire ST5 5BG, UK.
| | - Thomas H Gillingwater
- Centre for Integrative Physiology, University of Edinburgh, UK; Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, UK
| | - Thomas M Wishart
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, UK; Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, UK.
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24
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Kolb SJ, Coffey CS, Yankey JW, Krosschell K, Arnold WD, Rutkove SB, Swoboda KJ, Reyna SP, Sakonju A, Darras BT, Shell R, Kuntz N, Castro D, Iannaccone ST, Parsons J, Connolly AM, Chiriboga CA, McDonald C, Burnette WB, Werner K, Thangarajh M, Shieh PB, Finanger E, Cudkowicz ME, McGovern MM, McNeil DE, Finkel R, Kaye E, Kingsley A, Renusch SR, McGovern VL, Wang X, Zaworski PG, Prior TW, Burghes AHM, Bartlett A, Kissel JT. Baseline results of the NeuroNEXT spinal muscular atrophy infant biomarker study. Ann Clin Transl Neurol 2016; 3:132-45. [PMID: 26900585 PMCID: PMC4748311 DOI: 10.1002/acn3.283] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 10/30/2015] [Accepted: 12/10/2015] [Indexed: 01/09/2023] Open
Abstract
OBJECTIVE This study prospectively assessed putative promising biomarkers for use in assessing infants with spinal muscular atrophy (SMA). METHODS This prospective, multi-center natural history study targeted the enrollment of SMA infants and healthy control infants less than 6 months of age. Recruitment occurred at 14 centers within the NINDS National Network for Excellence in Neuroscience Clinical Trials (NeuroNEXT) Network. Infant motor function scales and putative electrophysiological, protein and molecular biomarkers were assessed at baseline and subsequent visits. RESULTS Enrollment began November, 2012 and ended September, 2014 with 26 SMA infants and 27 healthy infants enrolled. Baseline demographic characteristics of the SMA and control infant cohorts aligned well. Motor function as assessed by the Test for Infant Motor Performance Items (TIMPSI) and the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND) revealed significant differences between the SMA and control infants at baseline. Ulnar compound muscle action potential amplitude (CMAP) in SMA infants (1.4 ± 2.2 mV) was significantly reduced compared to controls (5.5 ± 2.0 mV). Electrical impedance myography (EIM) high-frequency reactance slope (Ohms/MHz) was significantly higher in SMA infants than controls SMA infants had lower survival motor neuron (SMN) mRNA levels in blood than controls, and several serum protein analytes were altered between cohorts. INTERPRETATION By the time infants were recruited and presented for the baseline visit, SMA infants had reduced motor function compared to controls. Ulnar CMAP, EIM, blood SMN mRNA levels, and serum protein analytes were able to distinguish between cohorts at the enrollment visit.
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Affiliation(s)
- Stephen J Kolb
- Department of Neurology The Ohio State University Wexner Medical Center Columbus Ohio; Department of Biological Chemistry & Pharmacology The Ohio State University Wexner Medical Center Columbus Ohio
| | - Christopher S Coffey
- Department of Biostatistics Neuro NEXT Data Coordinating Center University of Iowa Iowa City Iowa
| | - Jon W Yankey
- Department of Biostatistics Neuro NEXT Data Coordinating Center University of Iowa Iowa City Iowa
| | - Kristin Krosschell
- Departments of Physical Therapy and Human Movement Sciences and Pediatrics Northwestern University Feinberg School of Medicine Chicago Illinois
| | - W David Arnold
- Department of Neurology The Ohio State University Wexner Medical Center Columbus Ohio; Department of Physical Medicine and Rehabilitation The Ohio State University Wexner Medical Center Columbus Ohio
| | - Seward B Rutkove
- Department of Neurology Beth Israel Deaconess Medical Center Boston Massachusetts
| | - Kathryn J Swoboda
- Departments of Neurology and Pediatrics University of Utah Salt Lake City Utah; Department of Neurology Neuro NEXT Clinical Coordinating Center Massachusetts General Hospital Boston Massachusetts
| | - Sandra P Reyna
- Departments of Neurology and Pediatrics University of Utah Salt Lake City Utah; Department of Neurology Neuro NEXT Clinical Coordinating Center Massachusetts General Hospital Boston Massachusetts
| | - Ai Sakonju
- Departments of Neurology and Pediatrics University of Utah Salt Lake City Utah
| | - Basil T Darras
- Department of Neurology Boston Children's Hospital Boston Massachusetts
| | | | - Nancy Kuntz
- Ann & Robert H. Lurie Children's Hospital of Chicago Chicago Illinois
| | | | | | - Julie Parsons
- Children's Hospital Colorado, University of Colorado School of Medicine Aurora Colorado
| | - Anne M Connolly
- Washington University School of Medicine in St. Louis St. Louis Missouri
| | - Claudia A Chiriboga
- Department of Neurology Columbia College of Physicians and Surgeons New York New York
| | | | | | | | | | - Perry B Shieh
- University of California - Los Angeles Los Angeles California
| | | | - Merit E Cudkowicz
- Department of Neurology Neuro NEXT Clinical Coordinating Center Massachusetts General Hospital Boston Massachusetts
| | - Michelle M McGovern
- Department of Neurology Neuro NEXT Clinical Coordinating Center Massachusetts General Hospital Boston Massachusetts
| | - D Elizabeth McNeil
- National Institute of Neurological Disorders and Stroke Bethesda Maryland
| | | | - Edward Kaye
- Sarepta Therapeutics Cambridge Massachusetts
| | - Allison Kingsley
- Department of Neurology The Ohio State University Wexner Medical Center Columbus Ohio
| | - Samantha R Renusch
- Department of Biological Chemistry & Pharmacology The Ohio State University Wexner Medical Center Columbus Ohio
| | - Vicki L McGovern
- Department of Biological Chemistry & Pharmacology The Ohio State University Wexner Medical Center Columbus Ohio
| | - Xueqian Wang
- Department of Biological Chemistry & Pharmacology The Ohio State University Wexner Medical Center Columbus Ohio
| | | | - Thomas W Prior
- Department of Molecular Pathology Ohio State Wexner Medical Center Columbus Ohio
| | - Arthur H M Burghes
- Department of Biological Chemistry & Pharmacology The Ohio State University Wexner Medical Center Columbus Ohio
| | - Amy Bartlett
- Department of Neurology The Ohio State University Wexner Medical Center Columbus Ohio
| | - John T Kissel
- Department of Neurology The Ohio State University Wexner Medical Center Columbus Ohio
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25
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Wertz MH, Sahin M. Developing therapies for spinal muscular atrophy. Ann N Y Acad Sci 2015; 1366:5-19. [PMID: 26173388 DOI: 10.1111/nyas.12813] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 05/05/2015] [Accepted: 05/18/2015] [Indexed: 12/17/2022]
Abstract
Spinal muscular atrophy is an autosomal-recessive pediatric neurodegenerative disease characterized by loss of spinal motor neurons. It is caused by mutation in the gene survival of motor neuron 1 (SMN1), leading to loss of function of the full-length SMN protein. SMN has a number of functions in neurons, including RNA splicing and snRNP biogenesis in the nucleus, and RNA trafficking in neurites. The expression level of full-length SMN protein from the SMN2 locus modifies disease severity. Increasing full-length SMN protein by a small amount can lead to significant improvements in the neurological phenotype. Currently available interventions for spinal muscular atrophy patients are physical therapy and orthopedic, nutritional, and pulmonary interventions; these are palliative or supportive measures and do not address the etiology of the disease. In the past decade, there has been a push for developing therapeutics to improve motor phenotypes and increase life span of spinal muscular atrophy patients. These therapies are aimed primarily at restoration of full-length SMN protein levels, but other neuroprotective treatments have been investigated as well. Here, we discuss recent advances in basic and clinical studies toward finding safe and effective treatments of spinal muscular atrophy using gene therapy, antisense oligonucleotides, and other small molecule modulators of SMN expression.
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Affiliation(s)
- Mary H Wertz
- The F.M. Kirby Neurobiology Center, Department of Neurology, Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts
| | - Mustafa Sahin
- The F.M. Kirby Neurobiology Center, Department of Neurology, Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts
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26
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Finkel R, Bertini E, Muntoni F, Mercuri E. 209th ENMC International Workshop: Outcome Measures and Clinical Trial Readiness in Spinal Muscular Atrophy 7-9 November 2014, Heemskerk, The Netherlands. Neuromuscul Disord 2015; 25:593-602. [PMID: 26045156 DOI: 10.1016/j.nmd.2015.04.009] [Citation(s) in RCA: 147] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 10/23/2022]
Affiliation(s)
| | - Enrico Bertini
- UCL Institute of Child Health, Dubowitz Neuromuscular Centre, London, UK
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27
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Abstract
Spinal muscular atrophies (SMAs) are a group of inherited disorders characterized by motor neuron loss in the spinal cord and lower brainstem, muscle weakness, and atrophy. The clinical and genetic phenotypes incorporate a wide spectrum that is differentiated based on age of onset, pattern of muscle involvement, and inheritance pattern. Over the past several years, rapid advances in genetic technology have accelerated the identification of causative genes and provided important advances in understanding the molecular and biological basis of SMA and insights into the selective vulnerability of the motor neuron. Common pathophysiological themes include defects in RNA metabolism and splicing, axonal transport, and motor neuron development and connectivity. Together these have revealed potential novel treatment strategies, and extensive efforts are being undertaken towards expedited therapeutics. While a number of promising therapies for SMA are emerging, defining therapeutic windows and developing sensitive and relevant biomarkers are critical to facilitate potential success in clinical trials. This review incorporates an overview of the clinical manifestations and genetics of SMA, and describes recent advances in the understanding of mechanisms of disease pathogenesis and development of novel treatment strategies.
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Affiliation(s)
- Michelle A. Farrar
- />Discipline of Paediatrics, School of Women’s and Children’s Health, UNSW Medicine, The University of New South Wales, Sydney, Australia
- />Neurosciences Research Australia, Randwick, NSW Australia
- />Department of Neurology, Sydney Children’s Hospital, Randwick, NSW 2031 Australia
| | - Matthew C. Kiernan
- />Neurosciences Research Australia, Randwick, NSW Australia
- />Brain & Mind Research Institute, University of Sydney, Sydney, Australia
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28
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Edens BM, Ajroud-Driss S, Ma L, Ma YC. Molecular mechanisms and animal models of spinal muscular atrophy. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1852:685-92. [PMID: 25088406 DOI: 10.1016/j.bbadis.2014.07.024] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 07/21/2014] [Accepted: 07/23/2014] [Indexed: 12/27/2022]
Abstract
Spinal muscular atrophy (SMA), the leading genetic cause of infant mortality, is characterized by the degeneration of spinal motor neurons and muscle atrophy. Although the genetic cause of SMA has been mapped to the Survival Motor Neuron1 (SMN1) gene, mechanisms underlying selective motor neuron degeneration in SMA remain largely unknown. Here we review the latest developments and our current understanding of the molecular mechanisms underlying SMA pathogenesis, focusing on the animal model systems that have been developed, as well as new diagnostic and treatment strategies that have been identified using these model systems. This article is part of a special issue entitled: Neuromuscular Diseases: Pathology and Molecular Pathogenesis.
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Affiliation(s)
- Brittany M Edens
- Departments of Pediatrics, Neurology and Physiology, Northwestern University Feinberg School of Medicine, Lurie Children's Hospital of Chicago Research Center, IL 60611, Chicago
| | | | - Long Ma
- State Key Laboratory of Medical Genetics, Central South University, Changsha, Hunan 410078, China
| | - Yong-Chao Ma
- Departments of Pediatrics, Neurology and Physiology, Northwestern University Feinberg School of Medicine, Lurie Children's Hospital of Chicago Research Center, IL 60611, Chicago.
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29
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Abstract
Neuropathologic findings within the central and peripheral nervous systems in patients with spinal muscular atrophy type I (SMA-I) were examined in relation to genetic, clinical, and electrophysiologic features. Five infants representing the full clinical spectrum of SMA-I were examined clinically for compound motor action potential amplitude and SMN2 gene copy number; morphologic analyses of postmortem central nervous system, neuromuscular junction, and muscle tissue samples were performed and SMN protein was assessed in muscle samples. The 2 clinically most severely affected patients had a single copy of the SMN2 gene; in addition to anterior horn cells, dorsal root ganglia, and thalamus, neuronal degeneration in them was widespread in the cerebral cortex, basal ganglia, pigmented nuclei, brainstem, and cerebellum. Two typical SMA-I patients and a milder case each had 2 copies of the SMN2 gene and more restricted neuropathologic abnormalities. Maturation of acetylcholine receptor subunits was delayed and the neuromuscular junctions were abnormally formed in the SMA-I patients. Thus, the neuropathologic findings in human SMA-I are similar to many findings in animal models; factors other than SMN2 copy number modify disease severity. We present a pathophysiologic model for SMA-I as a protein deficiency disease affecting a neuronal network with variable clinical thresholds. Because new treatment strategies improve survival of infants with SMA-I, a better understanding of these factors will guide future treatments.
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30
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Hunter G, Roche SL, Somers E, Fuller HR, Gillingwater TH. The influence of storage parameters on measurement of survival motor neuron (SMN) protein levels: implications for pre-clinical studies and clinical trials for spinal muscular atrophy. Neuromuscul Disord 2014; 24:973-7. [PMID: 25047670 DOI: 10.1016/j.nmd.2014.05.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 05/22/2014] [Accepted: 05/30/2014] [Indexed: 12/18/2022]
Abstract
Spinal muscular atrophy (SMA) is caused by low levels of survival motor neuron (SMN) protein. A growing number of potential therapeutic strategies for SMA are entering pre-clinical and clinical testing, including gene therapy and antisense oligonucleotide-based approaches. For many such studies SMN protein levels are used as one major readout of treatment efficacy, often necessitating comparisons between samples obtained at different times and/or using different protocols. Whether differences in tissue sampling strategies or storage parameters have an influence on measurable SMN levels remains to be determined. We assessed murine SMN protein immunoreactivity over time and under differing tissue storage conditions. SMN protein levels, measured using sensitive quantitative fluorescent western blotting, declined rapidly over a period of several days following sample collection, especially when protein was extracted immediately and stored at -20°C. Storage of samples at lower temperatures (-80°C), and as intact tissue, led to significantly better preservation of SMN immunoreactivity. However, considerable deterioration in measurable SMN levels occurred, even under optimal storage conditions. These issues need to be taken into consideration when designing and interpreting pre-clinical and clinical SMA studies where SMN protein levels are being measured.
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Affiliation(s)
- Gillian Hunter
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH16 4SB, UK; Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Sarah L Roche
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH16 4SB, UK; Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Eilidh Somers
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH16 4SB, UK; Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Heidi R Fuller
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, UK
| | - Thomas H Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH16 4SB, UK; Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK; Institute for Science and Technology in Medicine, Keele University, Keele, UK.
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31
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Scotton C, Passarelli C, Neri M, Ferlini A. Biomarkers in rare neuromuscular diseases. Exp Cell Res 2013; 325:44-9. [PMID: 24389168 DOI: 10.1016/j.yexcr.2013.12.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 12/18/2013] [Indexed: 12/13/2022]
Abstract
Neuromuscular diseases (NMDs) comprise a range of rare disorders that include both hereditary peripheral neuropathies and myopathies. The heterogeneity and rarity of neuromuscular disorders are challenges for researchers seeking to develop effective diagnosis and treatment strategies. In particular, clinical trials of new therapies are made more difficult due to lack of reliable and monitorable clinical outcome measures. Biomarkers could be a way to speed up research in this field, shedding light on the pathophysiological mechanisms behind such diseases and providing invaluable tools for monitoring their progression, prognosis and response to drug treatment. Furthermore, biomarkers could represent a surrogate endpoint for clinical trials, enabling better stratification of patient cohorts through more accurate diagnosis and prognosis prediction. This review summarizes the types, applications, characteristics and best strategies for biomarker discovery to date.
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Affiliation(s)
- Chiara Scotton
- Section of Microbiology and Medical Genetics, Department of Medical Science, University of Ferrara, Ferrara, Italy
| | - Chiara Passarelli
- Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Diseases, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Marcella Neri
- Section of Microbiology and Medical Genetics, Department of Medical Science, University of Ferrara, Ferrara, Italy
| | - Alessandra Ferlini
- Section of Microbiology and Medical Genetics, Department of Medical Science, University of Ferrara, Ferrara, Italy.
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32
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Mutsaers CA, Lamont DJ, Hunter G, Wishart TM, Gillingwater TH. Label-free proteomics identifies Calreticulin and GRP75/Mortalin as peripherally accessible protein biomarkers for spinal muscular atrophy. Genome Med 2013; 5:95. [PMID: 24134804 PMCID: PMC3979019 DOI: 10.1186/gm498] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 10/09/2013] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is a neuromuscular disease resulting from mutations in the survival motor neuron 1 (SMN1) gene. Recent breakthroughs in preclinical research have highlighted several potential novel therapies for SMA, increasing the need for robust and sensitive clinical trial platforms for evaluating their effectiveness in human patient cohorts. Given that most clinical trials for SMA are likely to involve young children, there is a need for validated molecular biomarkers to assist with monitoring disease progression and establishing the effectiveness of therapies being tested. Proteomics technologies have recently been highlighted as a potentially powerful tool for such biomarker discovery. METHODS We utilized label-free proteomics to identify individual proteins in pathologically-affected skeletal muscle from SMA mice that report directly on disease status. Quantitative fluorescent western blotting was then used to assess whether protein biomarkers were robustly changed in muscle, skin and blood from another mouse model of SMA, as well as in a small cohort of human SMA patient muscle biopsies. RESULTS By comparing the protein composition of skeletal muscle in SMA mice at a pre-symptomatic time-point with the muscle proteome at a late-symptomatic time-point we identified increased expression of both Calreticulin and GRP75/Mortalin as robust indicators of disease progression in SMA mice. We report that these protein biomarkers were consistently modified in different mouse models of SMA, as well as across multiple skeletal muscles, and were also measurable in skin biopsies. Furthermore, Calreticulin and GRP75/Mortalin were measurable in muscle biopsy samples from human SMA patients. CONCLUSIONS We conclude that label-free proteomics technology provides a powerful platform for biomarker identification in SMA, revealing Calreticulin and GRP75/Mortalin as peripherally accessible protein biomarkers capable of reporting on disease progression in samples of muscle and skin.
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Affiliation(s)
- Chantal A Mutsaers
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH8 9XD, UK,Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Douglas J Lamont
- 'FingerPrints’ Proteomics Facility, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Gillian Hunter
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH8 9XD, UK,Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - Thomas M Wishart
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH8 9XD, UK,Division of Neurobiology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, EH25 9RG, UK
| | - Thomas H Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, EH8 9XD, UK,Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
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Tiziano FD, Melki J, Simard LR. Solving the puzzle of spinal muscular atrophy: what are the missing pieces? Am J Med Genet A 2013; 161A:2836-45. [PMID: 24124019 DOI: 10.1002/ajmg.a.36251] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2013] [Accepted: 08/30/2013] [Indexed: 12/13/2022]
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive, lower motor neuron disease. Clinical heterogeneity is pervasive: three infantile (type I-III) and one adult-onset (type IV) forms are recognized. Type I SMA is the most common genetic cause of death in infancy and accounts for about 50% of all patients with SMA. Most forms of SMA are caused by mutations of the survival motor neuron (SMN1) gene. A second gene that is 99% identical to SMN1 (SMN2) is located in the same region. The only functionally relevant difference between the two genes identified to date is a C → T transition in exon 7 of SMN2, which determines an alternative spliced isoform that predominantly excludes exon 7. Thus, SMN2 genes do not produce sufficient full length SMN protein to prevent the onset of the disease. Since the identification of the causative mutation, biomedical research of SMA has progressed by leaps and bounds: from clues on the function of SMN protein, to the development of different models of the disease, to the identification of potential treatments, some of which are currently in human trials. The aim of this review is to elucidate the current state of knowledge, emphasizing how close we are to the solution of the puzzle that is SMA, and, more importantly, to highlight the missing pieces of this puzzle. Filling in these gaps in our knowledge will likely accelerate the development and delivery of efficient treatments for SMA patients and be a prerequisite towards achieving our final goal, the cure of SMA.
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Seo J, Howell MD, Singh NN, Singh RN. Spinal muscular atrophy: an update on therapeutic progress. Biochim Biophys Acta Mol Basis Dis 2013; 1832:2180-90. [PMID: 23994186 DOI: 10.1016/j.bbadis.2013.08.005] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 07/27/2013] [Accepted: 08/14/2013] [Indexed: 12/24/2022]
Abstract
Humans have two nearly identical copies of survival motor neuron gene: SMN1 and SMN2. Deletion or mutation of SMN1 combined with the inability of SMN2 to compensate for the loss of SMN1 results in spinal muscular atrophy (SMA), a leading genetic cause of infant mortality. SMA affects 1 in ~6000 live births, a frequency much higher than in several genetic diseases. The major known defect of SMN2 is the predominant exon 7 skipping that leads to production of a truncated protein (SMNΔ7), which is unstable. Therefore, SMA has emerged as a model genetic disorder in which almost the entire disease population could be linked to the aberrant splicing of a single exon (i.e. SMN2 exon 7). Diverse treatment strategies aimed at improving the function of SMN2 have been envisioned. These strategies include, but are not limited to, manipulation of transcription, correction of aberrant splicing and stabilization of mRNA, SMN and SMNΔ7. This review summarizes up to date progress and promise of various in vivo studies reported for the treatment of SMA.
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Affiliation(s)
- Joonbae Seo
- Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
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