1
|
Tapken I, Detering NT, Claus P. What could be the function of the spinal muscular atrophy-causing protein SMN in macrophages? Front Immunol 2024; 15:1375428. [PMID: 38863697 PMCID: PMC11165114 DOI: 10.3389/fimmu.2024.1375428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 05/06/2024] [Indexed: 06/13/2024] Open
Abstract
Spinal Muscular Atrophy (SMA), a neurodegenerative disorder, extends its impact beyond the nervous system. The central protein implicated in SMA, Survival Motor Neuron (SMN) protein, is ubiquitously expressed and functions in fundamental processes such as alternative splicing, translation, cytoskeletal dynamics and signaling. These processes are relevant for all cellular systems, including cells of the immune system such as macrophages. Macrophages are capable of modulating their splicing, cytoskeleton and expression profile in order to fulfil their role in tissue homeostasis and defense. However, less is known about impairment or dysfunction of macrophages lacking SMN and the subsequent impact on the immune system of SMA patients. We aimed to review the potential overlaps between SMN functions and macrophage mechanisms highlighting the need for future research, as well as the current state of research addressing the role of macrophages in SMA.
Collapse
Affiliation(s)
- Ines Tapken
- SMATHERIA gGmbH – Non-Profit Biomedical Research Institute, Hannover, Germany
- Center for Systems Neuroscience (ZSN), Hannover, Germany
| | - Nora T. Detering
- SMATHERIA gGmbH – Non-Profit Biomedical Research Institute, Hannover, Germany
- Center for Systems Neuroscience (ZSN), Hannover, Germany
| | - Peter Claus
- SMATHERIA gGmbH – Non-Profit Biomedical Research Institute, Hannover, Germany
- Center for Systems Neuroscience (ZSN), Hannover, Germany
| |
Collapse
|
2
|
Matera AG, Steiner RE, Mills CA, Herring LE, Garcia EL. Chaperoning the chaperones: Proteomic analysis of the SMN complex reveals conserved and etiologic connections to the proteostasis network. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.15.594402. [PMID: 38903116 PMCID: PMC11188114 DOI: 10.1101/2024.05.15.594402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
Molecular chaperones and co-chaperones are highly conserved cellular components that perform variety of duties related to the proper three-dimensional folding of the proteome. The web of factors that carries out this essential task is called the proteostasis network (PN). Ribonucleoproteins (RNPs) represent an underexplored area in terms of the connections they make with the PN. The Survival Motor Neuron (SMN) complex is an RNP assembly chaperone and serves as a paradigm for studying how specific small nuclear (sn)RNAs are identified and paired with their client substrate proteins. SMN protein is the eponymous component of a large complex required for the biogenesis of uridine-rich small nuclear ribonucleoproteins (U-snRNPs) and localizes to distinct membraneless organelles in both the nucleus and cytoplasm of animal cells. SMN forms the oligomeric core of this complex, and missense mutations in its YG box self-interaction domain are known to cause Spinal Muscular Atrophy (SMA). The basic framework for understanding how snRNAs are assembled into U-snRNPs is known, the pathways and mechanisms used by cells to regulate their biogenesis are poorly understood. Given the importance of these processes to normal development as well as neurodegenerative disease, we set out to identify and characterize novel SMN binding partners. Here, we carried out affinity purification mass spectrometry (AP-MS) of SMN using stable fly lines exclusively expressing either wildtype or SMA-causing missense alleles. Bioinformatic analyses of the pulldown data, along with comparisons to proximity labeling studies carried out in human cells, revealed conserved connections to at least two other major chaperone systems including heat shock folding chaperones (HSPs) and histone/nucleosome assembly chaperones. Notably, we found that heat shock cognate protein Hsc70-4 and other HspA family members preferentially interacted with SMA-causing alleles of SMN. Hsc70-4 is particularly interesting because its mRNA is aberrantly sequestered by a mutant form of TDP-43 in mouse and Drosophila ALS (Amyotrophic Lateral Sclerosis) disease models. Most important, a missense allele of Hsc70-4 (HspA8 in mammals) was recently identified as a bypass suppressor of the SMA phenotype in mice. Collectively, these findings suggest that chaperone-related dysfunction lies at the etiological root of both ALS and SMA.
Collapse
Affiliation(s)
- A. Gregory Matera
- Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill NC, USA
- Departments of Biology and Genetics, University of North Carolina at Chapel Hill
- RNA Discovery and Lineberger Comprehensive Cancer Centers, University of North Carolina at Chapel Hill
| | - Rebecca E. Steiner
- Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill NC, USA
| | - C. Alison Mills
- Department of Pharmacology, University of North Carolina at Chapel Hill
| | - Laura E. Herring
- Department of Pharmacology, University of North Carolina at Chapel Hill
| | - Eric L. Garcia
- Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill NC, USA
- Department of Biology, University of Kentucky, Lexington KY, USA
| |
Collapse
|
3
|
Lu IN, Cheung PFY, Heming M, Thomas C, Giglio G, Leo M, Erdemir M, Wirth T, König S, Dambietz CA, Schroeter CB, Nelke C, Siveke JT, Ruck T, Klotz L, Haider C, Höftberger R, Kleinschnitz C, Wiendl H, Hagenacker T, Meyer Zu Horste G. Cell-mediated cytotoxicity within CSF and brain parenchyma in spinal muscular atrophy unaltered by nusinersen treatment. Nat Commun 2024; 15:4120. [PMID: 38750052 PMCID: PMC11096380 DOI: 10.1038/s41467-024-48195-3] [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: 06/15/2023] [Accepted: 04/24/2024] [Indexed: 05/18/2024] Open
Abstract
5q-associated spinal muscular atrophy (SMA) is a motoneuron disease caused by mutations in the survival motor neuron 1 (SMN1) gene. Adaptive immunity may contribute to SMA as described in other motoneuron diseases, yet mechanisms remain elusive. Nusinersen, an antisense treatment, enhances SMN2 expression, benefiting SMA patients. Here we have longitudinally investigated SMA and nusinersen effects on local immune responses in the cerebrospinal fluid (CSF) - a surrogate of central nervous system parenchyma. Single-cell transcriptomics (SMA: N = 9 versus Control: N = 9) reveal NK cell and CD8+ T cell expansions in untreated SMA CSF, exhibiting activation and degranulation markers. Spatial transcriptomics coupled with multiplex immunohistochemistry elucidate cytotoxicity near chromatolytic motoneurons (N = 4). Post-nusinersen treatment, CSF shows unaltered protein/transcriptional profiles. These findings underscore cytotoxicity's role in SMA pathogenesis and propose it as a therapeutic target. Our study illuminates cell-mediated cytotoxicity as shared features across motoneuron diseases, suggesting broader implications.
Collapse
Affiliation(s)
- I-Na Lu
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster, Germany
| | - Phyllis Fung-Yi Cheung
- Spatiotemporal Tumor Heterogeneity, German Cancer Consortium (DKTK), Partner Site Essen, A Partnership Between German Cancer Research Center (DKFZ) and University Hospital Essen, Essen, Germany
- Bridge Institute of Experimental Tumor Therapy, West German Cancer Center, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- Division of Solid Tumor Translational Oncology, DKTK, Partner Site Essen, A Partnership Between German Cancer Research Center (DKFZ) and University Hospital Essen, Essen, Germany
| | - Michael Heming
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster, Germany
| | - Christian Thomas
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
| | - Giovanni Giglio
- Spatiotemporal Tumor Heterogeneity, German Cancer Consortium (DKTK), Partner Site Essen, A Partnership Between German Cancer Research Center (DKFZ) and University Hospital Essen, Essen, Germany
- Bridge Institute of Experimental Tumor Therapy, West German Cancer Center, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- Division of Solid Tumor Translational Oncology, DKTK, Partner Site Essen, A Partnership Between German Cancer Research Center (DKFZ) and University Hospital Essen, Essen, Germany
| | - Markus Leo
- Department of Neurology and Center for Translational Neuro and Behavioral Science, University Hospital Essen, Essen, Germany
| | - Merve Erdemir
- Department of Neurology and Center for Translational Neuro and Behavioral Science, University Hospital Essen, Essen, Germany
| | - Timo Wirth
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster, Germany
| | - Simone König
- Core Unit Proteomics, Interdisciplinary Center for Clinical Research, University of Münster, Münster, Germany
| | - Christine A Dambietz
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster, Germany
| | - Christina B Schroeter
- Department of Neurology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Christopher Nelke
- Department of Neurology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Jens T Siveke
- Spatiotemporal Tumor Heterogeneity, German Cancer Consortium (DKTK), Partner Site Essen, A Partnership Between German Cancer Research Center (DKFZ) and University Hospital Essen, Essen, Germany
- Bridge Institute of Experimental Tumor Therapy, West German Cancer Center, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- Division of Solid Tumor Translational Oncology, DKTK, Partner Site Essen, A Partnership Between German Cancer Research Center (DKFZ) and University Hospital Essen, Essen, Germany
| | - Tobias Ruck
- Department of Neurology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Luisa Klotz
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster, Germany
| | - Carmen Haider
- Division of Neuropathology and Neurochemistry, Medical University of Vienna, Vienna, Austria
- Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Vienna, Austria
| | - Romana Höftberger
- Division of Neuropathology and Neurochemistry, Medical University of Vienna, Vienna, Austria
- Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Vienna, Austria
| | - Christoph Kleinschnitz
- Department of Neurology and Center for Translational Neuro and Behavioral Science, University Hospital Essen, Essen, Germany
| | - Heinz Wiendl
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster, Germany
| | - Tim Hagenacker
- Department of Neurology and Center for Translational Neuro and Behavioral Science, University Hospital Essen, Essen, Germany.
| | - Gerd Meyer Zu Horste
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster, Germany.
| |
Collapse
|
4
|
Karafoulidou E, Kesidou E, Theotokis P, Konstantinou C, Nella MK, Michailidou I, Touloumi O, Polyzoidou E, Salamotas I, Einstein O, Chatzisotiriou A, Boziki MK, Grigoriadis N. Systemic LPS Administration Stimulates the Activation of Non-Neuronal Cells in an Experimental Model of Spinal Muscular Atrophy. Cells 2024; 13:785. [PMID: 38727321 PMCID: PMC11083572 DOI: 10.3390/cells13090785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/27/2024] [Accepted: 05/02/2024] [Indexed: 05/13/2024] Open
Abstract
Spinal muscular atrophy (SMA) is a neurodegenerative disease caused by deficiency of the survival motor neuron (SMN) protein. Although SMA is a genetic disease, environmental factors contribute to disease progression. Common pathogen components such as lipopolysaccharides (LPS) are considered significant contributors to inflammation and have been associated with muscle atrophy, which is considered a hallmark of SMA. In this study, we used the SMNΔ7 experimental mouse model of SMA to scrutinize the effect of systemic LPS administration, a strong pro-inflammatory stimulus, on disease outcome. Systemic LPS administration promoted a reduction in SMN expression levels in CNS, peripheral lymphoid organs, and skeletal muscles. Moreover, peripheral tissues were more vulnerable to LPS-induced damage compared to CNS tissues. Furthermore, systemic LPS administration resulted in a profound increase in microglia and astrocytes with reactive phenotypes in the CNS of SMNΔ7 mice. In conclusion, we hereby show for the first time that systemic LPS administration, although it may not precipitate alterations in terms of deficits of motor functions in a mouse model of SMA, it may, however, lead to a reduction in the SMN protein expression levels in the skeletal muscles and the CNS, thus promoting synapse damage and glial cells' reactive phenotype.
Collapse
Affiliation(s)
- Eleni Karafoulidou
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| | - Evangelia Kesidou
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| | - Paschalis Theotokis
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| | - Chrystalla Konstantinou
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| | - Maria-Konstantina Nella
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| | - Iliana Michailidou
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| | - Olga Touloumi
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| | - Eleni Polyzoidou
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| | - Ilias Salamotas
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| | - Ofira Einstein
- Department of Physical Therapy, Faculty of Health Sciences, Ariel University, Ariel 40700, Israel;
| | - Athanasios Chatzisotiriou
- Department of Physiology, Medical School, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece;
| | - Marina-Kleopatra Boziki
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| | - Nikolaos Grigoriadis
- Laboratory of Experimental Neurology and Neuroimmunology, 2nd Neurological University Department, AHEPA General Hospital of Thessaloniki, Faculty of Health Science, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (E.K.); (E.K.); (P.T.); (C.K.); (M.-K.N.); (I.M.); (O.T.); (E.P.); (I.S.)
| |
Collapse
|
5
|
Garcia EL, Steiner RE, Raimer AC, Herring LE, Matera AG, Spring AM. Dysregulation of innate immune signaling in animal models of spinal muscular atrophy. BMC Biol 2024; 22:94. [PMID: 38664795 PMCID: PMC11044505 DOI: 10.1186/s12915-024-01888-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Accepted: 04/16/2024] [Indexed: 04/28/2024] Open
Abstract
BACKGROUND Spinal muscular atrophy (SMA) is a devastating neuromuscular disease caused by hypomorphic loss of function in the survival motor neuron (SMN) protein. SMA presents across a broad spectrum of disease severity. Unfortunately, genetic models of intermediate SMA have been difficult to generate in vertebrates and are thus unable to address key aspects of disease etiology. To address these issues, we developed a Drosophila model system that recapitulates the full range of SMA severity, allowing studies of pre-onset biology as well as late-stage disease processes. RESULTS Here, we carried out transcriptomic and proteomic profiling of mild and intermediate Drosophila models of SMA to elucidate molecules and pathways that contribute to the disease. Using this approach, we elaborated a role for the SMN complex in the regulation of innate immune signaling. We find that mutation or tissue-specific depletion of SMN induces hyperactivation of the immune deficiency (IMD) and Toll pathways, leading to overexpression of antimicrobial peptides (AMPs) and ectopic formation of melanotic masses in the absence of an external challenge. Furthermore, the knockdown of downstream targets of these signaling pathways reduced melanotic mass formation caused by SMN loss. Importantly, we identify SMN as a negative regulator of a ubiquitylation complex that includes Traf6, Bendless, and Diap2 and plays a pivotal role in several signaling networks. CONCLUSIONS In alignment with recent research on other neurodegenerative diseases, these findings suggest that hyperactivation of innate immunity contributes to SMA pathology. This work not only provides compelling evidence that hyperactive innate immune signaling is a primary effect of SMN depletion, but it also suggests that the SMN complex plays a regulatory role in this process in vivo. In summary, immune dysfunction in SMA is a consequence of reduced SMN levels and is driven by cellular and molecular mechanisms that are conserved between insects and mammals.
Collapse
Affiliation(s)
- Eric L Garcia
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
- Department of Biology, University of Kentucky, Lexington, KY, USA
| | - Rebecca E Steiner
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
- RNA Discovery and Lineberger Comprehensive Cancer Centers, University of North Carolina at Chapel Hill, Chapel Hill, 27599, USA
- Present Address: Lake, Erie College of Osteopathic Medicine, Bradenton, FL, USA
| | - Amanda C Raimer
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, 27599, USA
- Present Address, Radford University, Radford, VA, USA
| | - Laura E Herring
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, USA
| | - A Gregory Matera
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, 27599, USA.
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, 27599, USA.
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, 27599, USA.
- RNA Discovery and Lineberger Comprehensive Cancer Centers, University of North Carolina at Chapel Hill, Chapel Hill, 27599, USA.
| | - Ashlyn M Spring
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC, 27402, USA.
| |
Collapse
|
6
|
Garcia EL, Steiner RE, Raimer AC, Herring LE, Matera AG, Spring AM. Dysregulation of innate immune signaling in animal models of Spinal Muscular Atrophy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.14.571739. [PMID: 38168196 PMCID: PMC10760185 DOI: 10.1101/2023.12.14.571739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Background Spinal Muscular Atrophy (SMA) is a devastating neuromuscular disease caused by hypomorphic loss of function in the Survival Motor Neuron (SMN) protein. SMA presents across broad spectrum of disease severity. Unfortunately, vertebrate models of intermediate SMA have been difficult to generate and are thus unable to address key aspects of disease etiology. To address these issues, we developed a Drosophila model system that recapitulates the full range of SMA severity, allowing studies of pre-onset biology as well as late-stage disease processes. Results Here, we carried out transcriptomic and proteomic profiling of mild and intermediate Drosophila models of SMA to elucidate molecules and pathways that contribute to the disease. Using this approach, we elaborated a role for the SMN complex in the regulation of innate immune signaling. We find that mutation or tissue-specific depletion of SMN induces hyperactivation of the Immune Deficiency (IMD) and Toll pathways, leading to overexpression of antimicrobial peptides (AMPs) and ectopic formation of melanotic masses in the absence of an external challenge. Furthermore, knockdown of downstream targets of these signaling pathways reduced melanotic mass formation caused by SMN loss. Importantly, we identify SMN as a negative regulator of an ubiquitylation complex that includes Traf6, Bendless and Diap2, and plays a pivotal role in several signaling networks. Conclusions In alignment with recent research on other neurodegenerative diseases, these findings suggest that hyperactivation of innate immunity contributes to SMA pathology. This work not only provides compelling evidence that hyperactive innate immune signaling is a primary effect of SMN depletion, but it also suggests that the SMN complex plays a regulatory role in this process in vivo. In summary, immune dysfunction in SMA is a consequence of reduced SMN levels and is driven by cellular and molecular mechanisms that are conserved between insects and mammals.
Collapse
Affiliation(s)
- Eric L. Garcia
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill NC, USA
- Department of Biology, University of Kentucky, Lexington KY, USA
| | - Rebecca E. Steiner
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill NC, USA
- Department of Biology, University of North Carolina at Chapel Hill
| | - Amanda C. Raimer
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill NC, USA
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill
| | - Laura E. Herring
- Department of Pharmacology, University of North Carolina at Chapel Hill
| | - A. Gregory Matera
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill NC, USA
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill
- Department of Biology, University of North Carolina at Chapel Hill
- Department of Genetics, University of North Carolina at Chapel Hill
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill
| | - Ashlyn M. Spring
- Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill NC, USA
- Department of Biology, University of North Carolina at Greensboro, Greensboro NC, USA
| |
Collapse
|
7
|
Valsecchi V, Errico F, Bassareo V, Marino C, Nuzzo T, Brancaccio P, Laudati G, Casamassa A, Grimaldi M, D'Amico A, Carta M, Bertini E, Pignataro G, D'Ursi AM, Usiello A. SMN deficiency perturbs monoamine neurotransmitter metabolism in spinal muscular atrophy. Commun Biol 2023; 6:1155. [PMID: 37957344 PMCID: PMC10643621 DOI: 10.1038/s42003-023-05543-1] [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: 05/03/2023] [Accepted: 11/03/2023] [Indexed: 11/15/2023] Open
Abstract
Beyond motor neuron degeneration, homozygous mutations in the survival motor neuron 1 (SMN1) gene cause multiorgan and metabolic defects in patients with spinal muscular atrophy (SMA). However, the precise biochemical features of these alterations and the age of onset in the brain and peripheral organs remain unclear. Using untargeted NMR-based metabolomics in SMA mice, we identify cerebral and hepatic abnormalities related to energy homeostasis pathways and amino acid metabolism, emerging already at postnatal day 3 (P3) in the liver. Through HPLC, we find that SMN deficiency induces a drop in cerebral norepinephrine levels in overt symptomatic SMA mice at P11, affecting the mRNA and protein expression of key genes regulating monoamine metabolism, including aromatic L-amino acid decarboxylase (AADC), dopamine beta-hydroxylase (DβH) and monoamine oxidase A (MAO-A). In support of the translational value of our preclinical observations, we also discovered that SMN upregulation increases cerebrospinal fluid norepinephrine concentration in Nusinersen-treated SMA1 patients. Our findings highlight a previously unrecognized harmful influence of low SMN levels on the expression of critical enzymes involved in monoamine metabolism, suggesting that SMN-inducing therapies may modulate catecholamine neurotransmission. These results may also be relevant for setting therapeutic approaches to counteract peripheral metabolic defects in SMA.
Collapse
Affiliation(s)
- Valeria Valsecchi
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, University of Naples "Federico II", 80131, Naples, Italy
| | - Francesco Errico
- Department of Agricultural Sciences, University of Naples "Federico II", 80055, Portici, Italy
- Laboratory of Translational Neuroscience, Ceinge Biotecnologie Avanzate, 80145, Naples, Italy
| | - Valentina Bassareo
- Department of Biomedical Sciences, University of Cagliari, 09042, Monserrato, Italy
| | - Carmen Marino
- Department of Pharmacy, University of Salerno, 84084, Fisciano, Salerno, Italy
| | - Tommaso Nuzzo
- Laboratory of Translational Neuroscience, Ceinge Biotecnologie Avanzate, 80145, Naples, Italy
- Department of Environmental, Biological and Pharmaceutical Science and Technologies, Università degli Studi della Campania "Luigi Vanvitelli", 81100, Caserta, Italy
| | - Paola Brancaccio
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, University of Naples "Federico II", 80131, Naples, Italy
| | - Giusy Laudati
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, University of Naples "Federico II", 80131, Naples, Italy
| | | | - Manuela Grimaldi
- Department of Pharmacy, University of Salerno, 84084, Fisciano, Salerno, Italy
| | - Adele D'Amico
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesù Children's Hospital IRCCS, 00163, Rome, Italy
| | - Manolo Carta
- Department of Biomedical Sciences, University of Cagliari, 09042, Monserrato, Italy
| | - Enrico Bertini
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesù Children's Hospital IRCCS, 00163, Rome, Italy
| | - Giuseppe Pignataro
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, University of Naples "Federico II", 80131, Naples, Italy
| | - Anna Maria D'Ursi
- Department of Pharmacy, University of Salerno, 84084, Fisciano, Salerno, Italy
| | - Alessandro Usiello
- Laboratory of Translational Neuroscience, Ceinge Biotecnologie Avanzate, 80145, Naples, Italy.
- Department of Environmental, Biological and Pharmaceutical Science and Technologies, Università degli Studi della Campania "Luigi Vanvitelli", 81100, Caserta, Italy.
| |
Collapse
|
8
|
Dysfunctional mitochondria accumulate in a skeletal muscle knockout model of Smn1, the causal gene of spinal muscular atrophy. Cell Death Dis 2023; 14:162. [PMID: 36849544 PMCID: PMC9971247 DOI: 10.1038/s41419-023-05573-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 01/07/2023] [Accepted: 01/09/2023] [Indexed: 03/01/2023]
Abstract
The approved gene therapies for spinal muscular atrophy (SMA), caused by loss of survival motor neuron 1 (SMN1), greatly ameliorate SMA natural history but are not curative. These therapies primarily target motor neurons, but SMN1 loss has detrimental effects beyond motor neurons and especially in muscle. Here we show that SMN loss in mouse skeletal muscle leads to accumulation of dysfunctional mitochondria. Expression profiling of single myofibers from a muscle specific Smn1 knockout mouse model revealed down-regulation of mitochondrial and lysosomal genes. Albeit levels of proteins that mark mitochondria for mitophagy were increased, morphologically deranged mitochondria with impaired complex I and IV activity and respiration and that produced excess reactive oxygen species accumulated in Smn1 knockout muscles, because of the lysosomal dysfunction highlighted by the transcriptional profiling. Amniotic fluid stem cells transplantation that corrects the SMN knockout mouse myopathic phenotype restored mitochondrial morphology and expression of mitochondrial genes. Thus, targeting muscle mitochondrial dysfunction in SMA may complement the current gene therapy.
Collapse
|
9
|
Nuzzo T, Russo R, Errico F, D’Amico A, Tewelde AG, Valletta M, Hassan A, Tosi M, Panicucci C, Bruno C, Bertini E, Chambery A, Pellizzoni L, Usiello A. Nusinersen mitigates neuroinflammation in severe spinal muscular atrophy patients. COMMUNICATIONS MEDICINE 2023; 3:28. [PMID: 36792810 PMCID: PMC9932014 DOI: 10.1038/s43856-023-00256-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 02/02/2023] [Indexed: 02/17/2023] Open
Abstract
BACKGROUND Neuroinflammation contributes to the onset and progression of neurodegenerative diseases, but has not been specifically investigated in patients affected by severe and milder forms of spinal muscular atrophy (SMA). METHODS In this two-center retrospective study, we investigated signatures of neuroinflammation in forty-eight pediatric male and female SMA1 (n = 18), male and female SMA2 (n = 19), and female SMA3 (n = 11) patients, as well as in a limited number of male and female non-neurological control subjects (n = 4). We employed a Bio-Plex multiplex system based on xMAP technology and performed targeted quantitative analysis of a wide range of pro- and anti-inflammatory cytokines (chemokines, interferons, interleukins, lymphokines and tumor necrosis factors) and neurotrophic factors in the cerebrospinal fluid (CSF) of the study cohort before and after Nusinersen treatment at loading and maintenance stages. RESULTS We find a significant increase in the levels of several pro-inflammatory cytokines (IL-6, IFN-γ, TNF-α, IL-2, IL-8, IL-12, IL-17, MIP-1α, MCP-1, and Eotaxin) and neurotrophic factors (PDGF-BB and VEGF) in the CSF of SMA1 patients relative to SMA2 and SMA3 individuals, who display levels in the range of controls. We also find that treatment with Nusinersen significantly reduces the CSF levels of some but not all of these neuroinflammatory molecules in SMA1 patients. Conversely, Nusinersen increases the CSF levels of proinflammatory G-CSF, IL-8, MCP-1, MIP-1α, and MIP-1β in SMA2 patients and decreases those of anti-inflammatory IL-1ra in SMA3 patients. CONCLUSIONS These findings highlight signatures of neuroinflammation that are specifically associated with severe SMA and the neuro-immunomodulatory effects of Nusinersen therapy.
Collapse
Affiliation(s)
- Tommaso Nuzzo
- grid.9841.40000 0001 2200 8888Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Caserta, Italy ,grid.511947.f0000 0004 1758 0953Laboratory of Translational Neuroscience, Ceinge Biotecnologie Avanzate Franco Salvatore, Naples, Italy
| | - Rosita Russo
- grid.9841.40000 0001 2200 8888Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Caserta, Italy
| | - Francesco Errico
- grid.511947.f0000 0004 1758 0953Laboratory of Translational Neuroscience, Ceinge Biotecnologie Avanzate Franco Salvatore, Naples, Italy ,grid.4691.a0000 0001 0790 385XDepartment of Agricultural Sciences, University of Naples “Federico II”, Portici, Italy
| | - Adele D’Amico
- grid.414125.70000 0001 0727 6809Unit of Neuromuscular and Neurodegenerative Disorders, Dept. Neurosciences, Bambino Gesu’ Children’s Hospital IRCCS, Roma, Italy
| | - Awet G. Tewelde
- grid.9841.40000 0001 2200 8888Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Caserta, Italy
| | - Mariangela Valletta
- grid.9841.40000 0001 2200 8888Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Caserta, Italy
| | - Amber Hassan
- grid.511947.f0000 0004 1758 0953Laboratory of Translational Neuroscience, Ceinge Biotecnologie Avanzate Franco Salvatore, Naples, Italy
| | - Michele Tosi
- grid.414125.70000 0001 0727 6809Unit of Neuromuscular and Neurodegenerative Disorders, Dept. Neurosciences, Bambino Gesu’ Children’s Hospital IRCCS, Roma, Italy
| | - Chiara Panicucci
- grid.419504.d0000 0004 1760 0109Center of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Claudio Bruno
- grid.419504.d0000 0004 1760 0109Center of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy ,grid.5606.50000 0001 2151 3065Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal, and Child Health - DINOGMI, University of Genoa, Genoa, Italy
| | - Enrico Bertini
- grid.414125.70000 0001 0727 6809Unit of Neuromuscular and Neurodegenerative Disorders, Dept. Neurosciences, Bambino Gesu’ Children’s Hospital IRCCS, Roma, Italy
| | - Angela Chambery
- grid.9841.40000 0001 2200 8888Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, Caserta, Italy
| | - Livio Pellizzoni
- grid.21729.3f0000000419368729Center for Motor Neuron Biology and Disease, Columbia University, New York, NY USA ,grid.21729.3f0000000419368729Department of Pathology and Cell Biology, Columbia University, New York, NY USA ,grid.21729.3f0000000419368729Department of Neurology, Columbia University, New York, NY USA
| | - Alessandro Usiello
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania "Luigi Vanvitelli", Caserta, Italy. .,Laboratory of Translational Neuroscience, Ceinge Biotecnologie Avanzate Franco Salvatore, Naples, Italy.
| |
Collapse
|
10
|
Qiu J, Wu L, Qu R, Jiang T, Bai J, Sheng L, Feng P, Sun J. History of development of the life-saving drug “Nusinersen” in spinal muscular atrophy. Front Cell Neurosci 2022; 16:942976. [PMID: 36035257 PMCID: PMC9414009 DOI: 10.3389/fncel.2022.942976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/20/2022] [Indexed: 11/21/2022] Open
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive disorder with an incidence of 1/6,000–1/10,000 and is the leading fatal disease among infants. Previously, there was no effective treatment for SMA. The first effective drug, nusinersen, was approved by the US FDA in December 2016, providing hope to SMA patients worldwide. The drug was introduced in the European Union in 2017 and China in 2019 and has so far saved the lives of several patients in most parts of the world. Nusinersen are fixed sequence antisense oligonucleotides with special chemical modifications. The development of nusinersen progressed through major scientific discoveries in medicine, genetics, biology, and other disciplines, wherein several scientists have made substantial contributions. In this article, we will briefly describe the pathogenesis and therapeutic strategies of SMA, summarize the timeline of important scientific findings during the development of nusinersen in a detailed, scientific, and objective manner, and finally discuss the implications of the development of nusinersen for SMA research.
Collapse
Affiliation(s)
- Jiaying Qiu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Nantong University, Nantong, China
- Department of Prenatal Screening and Diagnosis Center, Affiliated Maternity and Child Health Care Hospital of Nantong University, Nantong, China
| | - Liucheng Wu
- Laboratory Animal Center, Nantong University, Nantong, China
| | - Ruobing Qu
- Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, China
| | - Tao Jiang
- Institute of Neuroscience, Soochow University, Suzhou, China
| | - Jialin Bai
- College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Lei Sheng
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Pengchao Feng
- Nanjing Antisense Biopharmaceutical Co., Ltd, Nanjing, China
| | - Junjie Sun
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Nantong University, Nantong, China
- *Correspondence: Junjie Sun
| |
Collapse
|
11
|
Chehade L, Deguise MO, De Repentigny Y, Yaworski R, Beauvais A, Gagnon S, Hensel N, Kothary R. Suppression of the necroptotic cell death pathways improves survival in Smn2B/− mice. Front Cell Neurosci 2022; 16:972029. [PMID: 35990890 PMCID: PMC9381707 DOI: 10.3389/fncel.2022.972029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 07/11/2022] [Indexed: 11/13/2022] Open
Abstract
Spinal muscular atrophy (SMA) is a monogenic neuromuscular disease caused by low levels of the Survival Motor Neuron (SMN) protein. Motor neuron degeneration is the central hallmark of the disease. However, the SMN protein is ubiquitously expressed and depletion of the protein in peripheral tissues results in intrinsic disease manifestations, including muscle defects, independent of neurodegeneration. The approved SMN-restoring therapies have led to remarkable clinical improvements in SMA patients. Yet, the presence of a significant number of non-responders stresses the need for complementary therapeutic strategies targeting processes which do not rely solely on restoring SMN. Dysregulated cell death pathways are candidates for SMN-independent pathomechanisms in SMA. Receptor-interacting protein kinase 1 (RIPK1) and RIPK3 have been widely recognized as critical therapeutic targets of necroptosis, an important form of programmed cell death. In addition, Caspase-1 plays a fundamental role in inflammation and cell death. In this study, we evaluate the role of necroptosis, particularly RIPK3 and Caspase-1, in the Smn2B/− mouse model of SMA. We have generated a triple mutant (TKO), the Smn2B/−; Ripk3−/−; Casp1−/− mouse. TKO mice displayed a robust increase in survival and improved motor function compared to Smn2B/− mice. While there was no protection against motor neuron loss or neuromuscular junction pathology, larger muscle fibers were observed in TKO mice compared to Smn2B/− mice. Our study shows that necroptosis modulates survival, motor behavior and muscle fiber size independent of SMN levels and independent of neurodegeneration. Thus, small-molecule inhibitors of necroptosis as a combinatorial approach together with SMN-restoring drugs could be a future strategy for the treatment of SMA.
Collapse
Affiliation(s)
- Lucia Chehade
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
- Center for Neuromuscular Disease, University of Ottawa, Ottawa, ON, Canada
| | - Marc-Olivier Deguise
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
- Center for Neuromuscular Disease, University of Ottawa, Ottawa, ON, Canada
- Department of Pediatrics, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada
| | - Yves De Repentigny
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Rebecca Yaworski
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Ariane Beauvais
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Sabrina Gagnon
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Niko Hensel
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Rashmi Kothary
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
- Center for Neuromuscular Disease, University of Ottawa, Ottawa, ON, Canada
- Department of Medicine, University of Ottawa, Ottawa, ON, Canada
- Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, Canada
- *Correspondence: Rashmi Kothary
| |
Collapse
|
12
|
Restoring SMN Expression: An Overview of the Therapeutic Developments for the Treatment of Spinal Muscular Atrophy. Cells 2022; 11:cells11030417. [PMID: 35159227 PMCID: PMC8834523 DOI: 10.3390/cells11030417] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/14/2022] [Accepted: 01/24/2022] [Indexed: 02/06/2023] Open
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive neurodegenerative disorder and one of the most common genetic causes of infant death. It is characterized by progressive weakness of the muscles, loss of ambulation, and death from respiratory complications. SMA is caused by the homozygous deletion or mutations in the survival of the motor neuron 1 (SMN1) gene. Humans, however, have a nearly identical copy of SMN1 known as the SMN2 gene. The severity of the disease correlates inversely with the number of SMN2 copies present. SMN2 cannot completely compensate for the loss of SMN1 in SMA patients because it can produce only a fraction of functional SMN protein. SMN protein is ubiquitously expressed in the body and has a variety of roles ranging from assembling the spliceosomal machinery, autophagy, RNA metabolism, signal transduction, cellular homeostasis, DNA repair, and recombination. Motor neurons in the anterior horn of the spinal cord are extremely susceptible to the loss of SMN protein, with the reason still being unclear. Due to the ability of the SMN2 gene to produce small amounts of functional SMN, two FDA-approved treatment strategies, including an antisense oligonucleotide (AON) nusinersen and small-molecule risdiplam, target SMN2 to produce more functional SMN. On the other hand, Onasemnogene abeparvovec (brand name Zolgensma) is an FDA-approved adeno-associated vector 9-mediated gene replacement therapy that can deliver a copy of the human SMN1. In this review, we summarize the SMA etiology, the role of SMN, and discuss the challenges of the therapies that are approved for SMA treatment.
Collapse
|
13
|
Kray KM, McGovern VL, Chugh D, Arnold WD, Burghes AHM. Dual SMN inducing therapies can rescue survival and motor unit function in symptomatic ∆7SMA mice. Neurobiol Dis 2021; 159:105488. [PMID: 34425216 PMCID: PMC8502210 DOI: 10.1016/j.nbd.2021.105488] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 08/06/2021] [Accepted: 08/16/2021] [Indexed: 11/24/2022] Open
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive disease characterized by survival motor neuron (SMN) protein deficiency which results in motor neuron loss and muscle atrophy. SMA is caused by a mutation or deletion of the survival motor neuron 1 (SMN1) gene and retention of the nearly identical SMN2 gene. SMN2 contains a C to T change in exon 7 that results in exon 7 exclusion from 90% of transcripts. SMN protein lacking exon 7 is unstable and rapidly degraded. The remaining full-length transcripts from SMN2 are insufficient for normal motor neuron function leading to the development of SMA. Three different therapeutic approaches that increase full-length SMN (FL-SMN) protein production are approved for treatment of SMA patients. Studies in both animal models and humans have demonstrated increasing SMN levels prior to onset of symptoms provides the greatest therapeutic benefit. Treatment of SMA, after some motor neuron loss has occurred, is also effective but to a lesser degree. The SMN∆7 mouse model is a well characterized model of severe or type 1 SMA, dying at 14 days of age. Here we treated three groups of ∆7SMA mice starting before, roughly during, and after symptom onset to determine if combining two mechanistically distinct SMN inducing therapies could improve the therapeutic outcome both before and after motor neuron loss. We found, compared with individual therapies, that morpholino antisense oligonucleotide (ASO) directed against ISS-N1 combined with the small molecule compound RG7800 significantly increased FL-SMN transcript and protein production resulting in improved survival and weight of ∆7SMA mice. Moreover, when give late symptomatically, motor unit function was completely rescued with no loss in function at 100 days of age in the dual treatment group. We have therefore shown that this dual therapeutic approach successfully increases SMN protein and rescues motor function in symptomatic ∆7SMA mice.
Collapse
Affiliation(s)
- Kaitlyn M Kray
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, 1060 Carmack Road, Columbus, OH 43210, USA.
| | - Vicki L McGovern
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, 1060 Carmack Road, Columbus, OH 43210, USA.
| | - Deepti Chugh
- Department of Neurology, Neuromuscular Division, The Ohio State University Wexner Medical Center, 395 W. 12(th) Ave, Columbus, OH 43210, USA
| | - W David Arnold
- Department of Neurology, Neuromuscular Division, The Ohio State University Wexner Medical Center, 395 W. 12(th) Ave, Columbus, OH 43210, USA.
| | - Arthur H M Burghes
- Department of Biological Chemistry and Pharmacology, The Ohio State University Wexner Medical Center, 1060 Carmack Road, Columbus, OH 43210, USA; Department of Neurology, Neuromuscular Division, The Ohio State University Wexner Medical Center, 395 W. 12(th) Ave, Columbus, OH 43210, USA.
| |
Collapse
|
14
|
Salucci S, Bartoletti Stella A, Battistelli M, Burattini S, Bavelloni A, Cocco LI, Gobbi P, Faenza I. How Inflammation Pathways Contribute to Cell Death in Neuro-Muscular Disorders. Biomolecules 2021; 11:1109. [PMID: 34439778 PMCID: PMC8391499 DOI: 10.3390/biom11081109] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 12/13/2022] Open
Abstract
Neuro-muscular disorders include a variety of diseases induced by genetic mutations resulting in muscle weakness and waste, swallowing and breathing difficulties. However, muscle alterations and nerve depletions involve specific molecular and cellular mechanisms which lead to the loss of motor-nerve or skeletal-muscle function, often due to an excessive cell death. Morphological and molecular studies demonstrated that a high number of these disorders seem characterized by an upregulated apoptosis which significantly contributes to the pathology. Cell death involvement is the consequence of some cellular processes that occur during diseases, including mitochondrial dysfunction, protein aggregation, free radical generation, excitotoxicity and inflammation. The latter represents an important mediator of disease progression, which, in the central nervous system, is known as neuroinflammation, characterized by reactive microglia and astroglia, as well the infiltration of peripheral monocytes and lymphocytes. Some of the mechanisms underlying inflammation have been linked to reactive oxygen species accumulation, which trigger mitochondrial genomic and respiratory chain instability, autophagy impairment and finally neuron or muscle cell death. This review discusses the main inflammatory pathways contributing to cell death in neuro-muscular disorders by highlighting the main mechanisms, the knowledge of which appears essential in developing therapeutic strategies to prevent the consequent neuron loss and muscle wasting.
Collapse
Affiliation(s)
- Sara Salucci
- Department of Biomolecular Sciences (DiSB), Urbino University Carlo Bo, 61029 Urbino, Italy; (M.B.); (S.B.); (P.G.)
- Cellular Signalling Laboratory, Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, 40126 Bologna, Italy; (L.I.C.); (I.F.)
| | - Anna Bartoletti Stella
- Department of Diagnostic Experimental and Specialty Medicine (DIMES), University of Bologna, 40126 Bologna, Italy;
| | - Michela Battistelli
- Department of Biomolecular Sciences (DiSB), Urbino University Carlo Bo, 61029 Urbino, Italy; (M.B.); (S.B.); (P.G.)
| | - Sabrina Burattini
- Department of Biomolecular Sciences (DiSB), Urbino University Carlo Bo, 61029 Urbino, Italy; (M.B.); (S.B.); (P.G.)
| | - Alberto Bavelloni
- Laboratory of Experimental Oncology, IRCCS Istituto Ortopedico Rizzoli, 40136 Bologna, Italy;
| | - Lucio Ildebrando Cocco
- Cellular Signalling Laboratory, Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, 40126 Bologna, Italy; (L.I.C.); (I.F.)
| | - Pietro Gobbi
- Department of Biomolecular Sciences (DiSB), Urbino University Carlo Bo, 61029 Urbino, Italy; (M.B.); (S.B.); (P.G.)
| | - Irene Faenza
- Cellular Signalling Laboratory, Department of Biomedical and NeuroMotor Sciences (DIBINEM), University of Bologna, 40126 Bologna, Italy; (L.I.C.); (I.F.)
| |
Collapse
|
15
|
Metabolic Dysfunction in Spinal Muscular Atrophy. Int J Mol Sci 2021; 22:ijms22115913. [PMID: 34072857 PMCID: PMC8198411 DOI: 10.3390/ijms22115913] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 05/25/2021] [Accepted: 05/29/2021] [Indexed: 12/11/2022] Open
Abstract
Spinal muscular atrophy (SMA) is an autosomal recessive genetic disorder leading to paralysis, muscle atrophy, and death. Significant advances in antisense oligonucleotide treatment and gene therapy have made it possible for SMA patients to benefit from improvements in many aspects of the once devastating natural history of the disease. How the depletion of survival motor neuron (SMN) protein, the product of the gene implicated in the disease, leads to the consequent pathogenic changes remains unresolved. Over the past few years, evidence toward a potential contribution of gastrointestinal, metabolic, and endocrine defects to disease phenotype has surfaced. These findings ranged from disrupted body composition, gastrointestinal tract, fatty acid, glucose, amino acid, and hormonal regulation. Together, these changes could have a meaningful clinical impact on disease traits. However, it is currently unclear whether these findings are secondary to widespread denervation or unique to the SMA phenotype. This review provides an in-depth account of metabolism-related research available to date, with a discussion of unique features compared to other motor neuron and related disorders.
Collapse
|
16
|
Deguise MO, Pileggi C, De Repentigny Y, Beauvais A, Tierney A, Chehade L, Michaud J, Llavero-Hurtado M, Lamont D, Atrih A, Wishart TM, Gillingwater TH, Schneider BL, Harper ME, Parson SH, Kothary R. SMN Depleted Mice Offer a Robust and Rapid Onset Model of Nonalcoholic Fatty Liver Disease. Cell Mol Gastroenterol Hepatol 2021; 12:354-377.e3. [PMID: 33545428 PMCID: PMC8257458 DOI: 10.1016/j.jcmgh.2021.01.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 02/08/2023]
Abstract
BACKGROUND & AIMS Nonalcoholic fatty liver disease (NAFLD) is considered a health epidemic with potential devastating effects on the patients and the healthcare systems. Current preclinical models of NAFLD are invariably imperfect and generally take a long time to develop. A mouse model of survival motor neuron (SMN) depletion (Smn2B/- mice) was recently shown to develop significant hepatic steatosis in less than 2 weeks from birth. The rapid onset of fatty liver in Smn2B/- mice provides an opportunity to identify molecular markers of NAFLD. Here, we investigated whether Smn2B/- mice display typical features of NAFLD/nonalcoholic steatohepatitis (NASH). METHODS Biochemical, histologic, electron microscopy, proteomic, and high-resolution respirometry were used. RESULTS The Smn2B/- mice develop microvesicular steatohepatitis within 2 weeks, a feature prevented by AAV9-SMN gene therapy. Although fibrosis is not overtly apparent in histologic sections of the liver, there is molecular evidence of fibrogenesis and presence of stellate cell activation. The consequent liver damage arises from mitochondrial reactive oxygen species production and results in hepatic dysfunction in protein output, complement, coagulation, iron homeostasis, and insulin-like growth factor-1 metabolism. The NAFLD phenotype is likely due to non-esterified fatty acid overload from peripheral lipolysis subsequent to hyperglucagonemia compounded by reduced muscle use and insulin resistance. Despite the low hepatic mitochondrial content, isolated mitochondria show enhanced β-oxidation, likely as a compensatory response, resulting in the production of reactive oxygen species. In contrast to typical NAFLD/NASH, the Smn2B/- mice lose weight because of their associated neurological condition (spinal muscular atrophy) and develop hypoglycemia. CONCLUSIONS The Smn2B/- mice represent a good model of microvesicular steatohepatitis. Like other models, it is not representative of the complete NAFLD/NASH spectrum. Nevertheless, it offers a reliable, low-cost, early-onset model that is not dependent on diet to identify molecular players in NAFLD pathogenesis and can serve as one of the very few models of microvesicular steatohepatitis for both adult and pediatric populations.
Collapse
Affiliation(s)
- Marc-Olivier Deguise
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada,Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario, Canada
| | - Chantal Pileggi
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Yves De Repentigny
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Ariane Beauvais
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Alexandra Tierney
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Lucia Chehade
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada,Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario, Canada
| | - Jean Michaud
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Maica Llavero-Hurtado
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom,The Roslin Institute, Royal (Dick) School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Douglas Lamont
- FingerPrints Proteomics Facility, University of Dundee, Dundee, United Kingdom
| | - Abdelmadjid Atrih
- FingerPrints Proteomics Facility, University of Dundee, Dundee, United Kingdom
| | - Thomas M. Wishart
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom,The Roslin Institute, Royal (Dick) School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Thomas H. Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom,College of Medicine & Veterinary Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Bernard L. Schneider
- Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland,Bertarelli Foundation Gene Therapy Platform, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Geneva, Switzerland
| | - Mary-Ellen Harper
- Department of Biochemistry, Microbiology and Immunology, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Simon H. Parson
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom,Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Rashmi Kothary
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada,Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario, Canada,Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada,Correspondence Address correspondence to: Rashmi Kothary, PhD, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario, Canada K1H 8L6. fax: (613) 737-8803.
| |
Collapse
|
17
|
Spinal muscular atrophy: Broad disease spectrum and sex-specific phenotypes. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166063. [PMID: 33412266 DOI: 10.1016/j.bbadis.2020.166063] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/14/2020] [Accepted: 12/21/2020] [Indexed: 12/17/2022]
Abstract
Spinal muscular atrophy (SMA) is one of the major genetic disorders associated with infant mortality. More than 90% of cases of SMA result from deletions of or mutations in the Survival Motor Neuron 1 (SMN1) gene. SMN2, a nearly identical copy of SMN1, does not compensate for the loss of SMN1 due to predominant skipping of exon 7. The spectrum of SMA is broad, ranging from prenatal death to infant mortality to survival into adulthood. All tissues, including brain, spinal cord, bone, skeletal muscle, heart, lung, liver, pancreas, gastrointestinal tract, kidney, spleen, ovary and testis, are directly and/or indirectly affected in SMA. Accumulating evidence on impaired mitochondrial biogenesis and defects in X chromosome-linked modifying factors, coupled with the sexual dimorphic nature of many tissues, point to sex-specific vulnerabilities in SMA. Here we review the role of sex in the pathogenesis of SMA.
Collapse
|
18
|
Besse A, Astord S, Marais T, Roda M, Giroux B, Lejeune FX, Relaix F, Smeriglio P, Barkats M, Biferi MG. AAV9-Mediated Expression of SMN Restricted to Neurons Does Not Rescue the Spinal Muscular Atrophy Phenotype in Mice. Mol Ther 2020; 28:1887-1901. [PMID: 32470325 PMCID: PMC7403319 DOI: 10.1016/j.ymthe.2020.05.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 03/30/2020] [Accepted: 05/12/2020] [Indexed: 01/13/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a neuromuscular disease mainly caused by mutations or deletions in the survival of motor neuron 1 (SMN1) gene and characterized by the degeneration of motor neurons and progressive muscle weakness. A viable therapeutic approach for SMA patients is a gene replacement strategy that restores functional SMN expression using adeno-associated virus serotype 9 (AAV9) vectors. Currently, systemic or intra-cerebrospinal fluid (CSF) delivery of AAV9-SMN is being explored in clinical trials. In this study, we show that the postnatal delivery of an AAV9 that expresses SMN under the control of the neuron-specific promoter synapsin selectively targets neurons without inducing re-expression in the peripheral organs of SMA mice. However, this approach is less efficient in restoring the survival and neuromuscular functions of SMA mice than the systemic or intra-CSF delivery of an AAV9 in which SMN is placed under the control of a ubiquitous promoter. This study suggests that further efforts are needed to understand the extent to which SMN is required in neurons and peripheral organs for a successful therapeutic effect.
Collapse
Affiliation(s)
- Aurore Besse
- Sorbonne Université, INSERM, Institute of Myology, Centre of Research in Myology, 75013 Paris, France
| | - Stephanie Astord
- Sorbonne Université, INSERM, Institute of Myology, Centre of Research in Myology, 75013 Paris, France
| | - Thibaut Marais
- Sorbonne Université, INSERM, Institute of Myology, Centre of Research in Myology, 75013 Paris, France
| | - Marianne Roda
- Sorbonne Université, INSERM, Institute of Myology, Centre of Research in Myology, 75013 Paris, France
| | - Benoit Giroux
- Sorbonne Université, INSERM, Institute of Myology, Centre of Research in Myology, 75013 Paris, France
| | - François-Xavier Lejeune
- Institut du Cerveau et de la Moelle épinière (ICM), Bioinformatics and Biostatistics Core Facility (iCONICS), Sorbonne Université, INSERM U1127, CNRS UMR 7225, GH Pitié-Salpêtrière, 75013 Paris, France
| | - Frederic Relaix
- Université Paris Est Créteil, INSERM, EnvA, AP-HP, 94000 Créteil, France
| | - Piera Smeriglio
- Sorbonne Université, INSERM, Institute of Myology, Centre of Research in Myology, 75013 Paris, France
| | - Martine Barkats
- Sorbonne Université, INSERM, Institute of Myology, Centre of Research in Myology, 75013 Paris, France
| | - Maria Grazia Biferi
- Sorbonne Université, INSERM, Institute of Myology, Centre of Research in Myology, 75013 Paris, France.
| |
Collapse
|
19
|
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.
Collapse
|
20
|
New and Developing Therapies in Spinal Muscular Atrophy: From Genotype to Phenotype to Treatment and Where Do We Stand? Int J Mol Sci 2020; 21:ijms21093297. [PMID: 32392694 PMCID: PMC7246502 DOI: 10.3390/ijms21093297] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 05/03/2020] [Accepted: 05/04/2020] [Indexed: 02/08/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a congenital neuromuscular disorder characterized by motor neuron loss, resulting in progressive weakness. SMA is notable in the health care community because it accounts for the most common cause of infant death resulting from a genetic defect. SMA is caused by low levels of the survival motor neuron protein (SMN) resulting from SMN1 gene mutations or deletions. However, patients always harbor various copies of SMN2, an almost identical but functionally deficient copy of the gene. A genotype–phenotype correlation suggests that SMN2 is a potent disease modifier for SMA, which also represents the primary target for potential therapies. Increasing comprehension of SMA pathophysiology, including the characterization of SMN1 and SMN2 genes and SMN protein functions, has led to the development of multiple therapeutic approaches. Until the end of 2016, no cure was available for SMA, and management consisted of supportive measures. Two breakthrough SMN-targeted treatments, either using antisense oligonucleotides (ASOs) or virus-mediated gene therapy, have recently been approved. These two novel therapeutics have a common objective: to increase the production of SMN protein in MNs and thereby improve motor function and survival. However, neither therapy currently provides a complete cure. Treating patients with SMA brings new responsibilities and unique dilemmas. As SMA is such a devastating disease, it is reasonable to assume that a unique therapeutic solution may not be sufficient. Current approaches under clinical investigation differ in administration routes, frequency of dosing, intrathecal versus systemic delivery, and mechanisms of action. Besides, emerging clinical trials evaluating the efficacy of either SMN-dependent or SMN-independent approaches are ongoing. This review aims to address the different knowledge gaps between genotype, phenotypes, and potential therapeutics.
Collapse
|
21
|
Deguise MO, De Repentigny Y, Tierney A, Beauvais A, Michaud J, Chehade L, Thabet M, Paul B, Reilly A, Gagnon S, Renaud JM, Kothary R. Motor transmission defects with sex differences in a new mouse model of mild spinal muscular atrophy. EBioMedicine 2020; 55:102750. [PMID: 32339936 PMCID: PMC7184161 DOI: 10.1016/j.ebiom.2020.102750] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 02/25/2020] [Accepted: 03/19/2020] [Indexed: 12/31/2022] Open
Abstract
Background Mouse models of mild spinal muscular atrophy (SMA) have been extremely challenging to generate. This paucity of model systems has limited our understanding of pathophysiological events in milder forms of the disease and of the effect of SMN depletion during aging. Methods A mild mouse model of SMA, termed Smn2B/−;SMN2+/−, was generated by crossing Smn−/−;SMN2 and Smn2B/2B mice. This new model was characterized using behavioral testing, histology, western blot, muscle-nerve electrophysiology as well as ultrasonography to study classical SMA features and extra-neuronal involvement. Findings Smn2B/−;SMN2+/− mice have normal survival, mild but sustained motor weakness, denervation and neuronal/neuromuscular junction (NMJ) transmission defects, and neurogenic muscle atrophy that are more prominent in male mice. Increased centrally located nuclei, intrinsic contractile and relaxation muscle defects were also identified in both female and male mice, with some male predominance. There was an absence of extra-neuronal pathology. Interpretation The Smn2B/−;SMN2+/− mouse provides a model of mild SMA, displaying some hallmark features including reduced weight, sustained motor weakness, electrophysiological transmission deficit, NMJ defects, and muscle atrophy. Early and prominent increase central nucleation and intrinsic electrophysiological deficits demonstrate the potential role played by muscle in SMA disease. The use of this model will allow for the understanding of the most susceptible pathogenic molecular changes in motor neurons and muscles, investigation of the effects of SMN depletion in aging, sex differences and most importantly will provide guidance for the currently aging SMA patients treated with the recently approved genetic therapies. Funding : This work was supported by Cure SMA/Families of SMA Canada (grant numbers KOT-1819 and KOT-2021); Muscular Dystrophy Association (USA) (grant number 575466); and Canadian Institutes of Health Research (CIHR) (grant number PJT-156379).
Collapse
Affiliation(s)
- Marc-Olivier Deguise
- Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada; Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Yves De Repentigny
- Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada
| | - Alexandra Tierney
- Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada
| | - Ariane Beauvais
- Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada
| | - Jean Michaud
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Lucia Chehade
- Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada; Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Mohamed Thabet
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Brittany Paul
- Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada; Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Aoife Reilly
- Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada; Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Sabrina Gagnon
- Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada
| | - Jean-Marc Renaud
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - Rashmi Kothary
- Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada; Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada; Department of Medicine, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada.
| |
Collapse
|
22
|
Muscle overexpression of Klf15 via an AAV8-Spc5-12 construct does not provide benefits in spinal muscular atrophy mice. Gene Ther 2020; 27:505-515. [PMID: 32313099 PMCID: PMC7674152 DOI: 10.1038/s41434-020-0146-8] [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: 07/28/2019] [Revised: 03/19/2020] [Accepted: 03/27/2020] [Indexed: 01/31/2023]
Abstract
Spinal muscular atrophy (SMA) is a neuromuscular disease caused by loss of the survival motor neuron (SMN) gene. While there are currently two approved gene-based therapies for SMA, availability, high cost, and differences in patient response indicate that alternative treatment options are needed. Optimal therapeutic strategies will likely be a combination of SMN-dependent and -independent treatments aimed at alleviating symptoms in the central nervous system and peripheral muscles. Krüppel-like factor 15 (KLF15) is a transcription factor that regulates key metabolic and ergogenic pathways in muscle. We have recently reported significant downregulation of Klf15 in muscle of presymptomatic SMA mice. Importantly, perinatal upregulation of Klf15 via transgenic and pharmacological methods resulted in improved disease phenotypes in SMA mice, including weight and survival. In the current study, we designed an adeno-associated virus serotype 8 (AAV8) vector to overexpress a codon-optimized Klf15 cDNA under the muscle-specific Spc5-12 promoter (AAV8-Klf15). Administration of AAV8-Klf15 to severe Taiwanese Smn−/−;SMN2 or intermediate Smn2B/− SMA mice significantly increased Klf15 expression in muscle. We also observed significant activity of the AAV8-Klf15 vector in liver and heart. AAV8-mediated Klf15 overexpression moderately improved survival in the Smn2B/− model but not in the Taiwanese mice. An inability to specifically induce Klf15 expression at physiological levels in a time- and tissue-dependent manner may have contributed to this limited efficacy. Thus, our work demonstrates that an AAV8-Spc5-12 vector induces high gene expression as early as P2 in several tissues including muscle, heart, and liver, but highlights the challenges of achieving meaningful vector-mediated transgene expression of Klf15.
Collapse
|
23
|
Nery FC, Siranosian JJ, Rosales I, Deguise MO, Sharma A, Muhtaseb AW, Nwe P, Johnstone AJ, Zhang R, Fatouraei M, Huemer N, Alves CRR, Kothary R, Swoboda KJ. Impaired kidney structure and function in spinal muscular atrophy. NEUROLOGY-GENETICS 2019; 5:e353. [PMID: 31517062 PMCID: PMC6705648 DOI: 10.1212/nxg.0000000000000353] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 06/25/2019] [Indexed: 01/24/2023]
Abstract
Objective To determine changes in serum profiles and kidney tissues from patients with spinal muscular atrophy (SMA) type 1 compared with age- and sex-matched controls. Methods In this cohort study, we investigated renal structure and function in infants and children with SMA type 1 in comparison with age- and sex-matched controls. Results Patients with SMA had alterations in serum creatinine, cystatin C, sodium, glucose, and calcium concentrations, granular casts and crystals in urine, and nephrocalcinosis and fibrosis. Nephrotoxicity and polycystic kidney disease PCR arrays revealed multiple differentially expressed genes, and immunoblot analysis showed decreased calcium-sensing receptors and calbindin and increased insulin-like growth factor-binding proteins in kidneys from patients with SMA. Conclusions These findings demonstrate that patients with SMA type 1, in the absence of disease-modifying therapies, frequently manifest impaired renal function as a primary or secondary consequence of their disease. This study provides new insights into systemic contributions to SMA disease pathogenesis and the need to identify coadjuvant therapies.
Collapse
Affiliation(s)
- Flávia C Nery
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Jennifer J Siranosian
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Ivy Rosales
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Marc-Olivier Deguise
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Amita Sharma
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Abdurrahman W Muhtaseb
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Pann Nwe
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Alec J Johnstone
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Ren Zhang
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Maryam Fatouraei
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Natassja Huemer
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Christiano R R Alves
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Rashmi Kothary
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| | - Kathryn J Swoboda
- Department of Neurology (F.C.N., J.J.S., A.W.M., P.N., A.J.J., R.Z., M.F., N.H., C.R.R.A., K.J.S.), Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA; Department of Pathology (I.R.), Massachusetts General Hospital, Boston, MA; Regenerative Medicine Program (M.-O.D., R.K.), Ottawa Hospital Research, Institute Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine (M.-O.D., R.K.), University of Ottawa, Canada; Centre for Neuromuscular Disease (M.-O.D., R.K.), University of Ottawa, Ottawa, Ontario, Canada; Division of Pediatric Nephrology (A.S.), Massachusetts General Hospital, Boston, MA; Department of Biology (N.H.), Federal University of São Carlos, Sorocaba, Sao Paulo, SP, Brazil; and Department of Medicine (R.K.), University of Ottawa, Ottawa, Ontario, Canada
| |
Collapse
|
24
|
Deguise M, Baranello G, Mastella C, Beauvais A, Michaud J, Leone A, De Amicis R, Battezzati A, Dunham C, Selby K, Warman Chardon J, McMillan HJ, Huang Y, Courtney NL, Mole AJ, Kubinski S, Claus P, Murray LM, Bowerman M, Gillingwater TH, Bertoli S, Parson SH, Kothary R. Abnormal fatty acid metabolism is a core component of spinal muscular atrophy. Ann Clin Transl Neurol 2019; 6:1519-1532. [PMID: 31402618 PMCID: PMC6689695 DOI: 10.1002/acn3.50855] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 07/09/2019] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVE Spinal muscular atrophy (SMA) is an inherited neuromuscular disorder leading to paralysis and subsequent death in young children. Initially considered a motor neuron disease, extra-neuronal involvement is increasingly recognized. The primary goal of this study was to investigate alterations in lipid metabolism in SMA patients and mouse models of the disease. METHODS We analyzed clinical data collected from a large cohort of pediatric SMA type I-III patients as well as SMA type I liver necropsy data. In parallel, we performed histology, lipid analysis, and transcript profiling in mouse models of SMA. RESULTS We identify an increased susceptibility to developing dyslipidemia in a cohort of 72 SMA patients and liver steatosis in pathological samples. Similarly, fatty acid metabolic abnormalities were present in all SMA mouse models studied. Specifically, Smn2B/- mice displayed elevated hepatic triglycerides and dyslipidemia, resembling non-alcoholic fatty liver disease (NAFLD). Interestingly, this phenotype appeared prior to denervation. INTERPRETATION This work highlights metabolic abnormalities as an important feature of SMA, suggesting implementation of nutritional and screening guidelines in patients, as such defects are likely to increase metabolic distress and cardiovascular risk. This study emphasizes the need for a systemic therapeutic approach to ensure maximal benefits for all SMA patients throughout their life.
Collapse
Affiliation(s)
- Marc‐Olivier Deguise
- Regenerative Medicine ProgramOttawa Hospital Research InstituteOttawaOntarioCanada
- Department of Cellular and Molecular MedicineUniversity of OttawaOttawaOntarioCanada
- Centre for Neuromuscular DiseaseUniversity of OttawaOttawaOntarioCanadaK1H 8M5
| | - Giovanni Baranello
- UO Neurologia dello SviluppoFondazione IRCCS Istituto Neurologico Carlo BestaMilanItaly
- The Dubowitz Neuromuscular CentreNIHR BRC University College London Great Ormond Street Institute of Child Health & Great Ormond Street HospitalLondonUnited Kingdom
| | - Chiara Mastella
- SAPRE‐UONPIA, Fondazione IRCCS Cà' Granda Ospedale Maggiore PoliclinicoMilanItaly
| | - Ariane Beauvais
- Regenerative Medicine ProgramOttawa Hospital Research InstituteOttawaOntarioCanada
| | - Jean Michaud
- Department of Pathology and Laboratory Medicine, Faculty of MedicineUniversity of OttawaOttawaOntarioCanada
| | - Alessandro Leone
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food, Environmental and Nutritional Sciences (DeFENS)University of MilanMilanItaly
| | - Ramona De Amicis
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food, Environmental and Nutritional Sciences (DeFENS)University of MilanMilanItaly
| | - Alberto Battezzati
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food, Environmental and Nutritional Sciences (DeFENS)University of MilanMilanItaly
| | - Christopher Dunham
- Division of Anatomic PathologyChildren's and Women's Health Centre of B.CVancouverBritish ColumbiaCanada
| | - Kathryn Selby
- Division of Neurology, Department of PediatricsBC Children's HospitalVancouverBritish ColumbiaCanada
| | - Jodi Warman Chardon
- Department of Cellular and Molecular MedicineUniversity of OttawaOttawaOntarioCanada
- Centre for Neuromuscular DiseaseUniversity of OttawaOttawaOntarioCanadaK1H 8M5
- Neuroscience Program, Ottawa Hospital Research InstituteOttawaOntarioCanada
- Department of PediatricsChildren's Hospital of Eastern OntarioOttawaOntarioCanada
- Department of MedicineUniversity of OttawaOttawaOntarioCanada
| | - Hugh J. McMillan
- Children's Hospital of Eastern Ontario Research InstituteUniversity of OttawaOttawaOntarioCanada
| | - Yu‐Ting Huang
- Euan MacDonald Centre for Motor Neurone Disease ResearchUniversity of EdinburghEdinburghUnited Kingdom
- College of Medicine & Veterinary MedicineUniversity of EdinburghEdinburghUnited Kingdom
| | - Natalie L. Courtney
- Euan MacDonald Centre for Motor Neurone Disease ResearchUniversity of EdinburghEdinburghUnited Kingdom
- College of Medicine & Veterinary MedicineUniversity of EdinburghEdinburghUnited Kingdom
- Centre for Discovery Brain ScienceUniversity of EdinburghEdinburghUnited Kingdom
| | - Alannah J. Mole
- Euan MacDonald Centre for Motor Neurone Disease ResearchUniversity of EdinburghEdinburghUnited Kingdom
- College of Medicine & Veterinary MedicineUniversity of EdinburghEdinburghUnited Kingdom
- Centre for Discovery Brain ScienceUniversity of EdinburghEdinburghUnited Kingdom
| | - Sabrina Kubinski
- Institute of Neuroanatomy and Cell BiologyHannover Medical SchoolHannoverGermany
- Center of Systems NeuroscienceHannoverGermany
| | - Peter Claus
- Institute of Neuroanatomy and Cell BiologyHannover Medical SchoolHannoverGermany
- Center of Systems NeuroscienceHannoverGermany
| | - Lyndsay M. Murray
- Euan MacDonald Centre for Motor Neurone Disease ResearchUniversity of EdinburghEdinburghUnited Kingdom
- College of Medicine & Veterinary MedicineUniversity of EdinburghEdinburghUnited Kingdom
- Centre for Discovery Brain ScienceUniversity of EdinburghEdinburghUnited Kingdom
| | - Melissa Bowerman
- School of MedicineKeele UniversityStaffordshireUnited Kingdom
- Institute for Science and Technology in MedicineStoke‐on‐TrentUnited Kingdom
- Wolfson Centre for Inherited Neuromuscular DiseaseRJAH Orthopaedic HospitalOswestryUnited Kingdom
| | - Thomas H. Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease ResearchUniversity of EdinburghEdinburghUnited Kingdom
- College of Medicine & Veterinary MedicineUniversity of EdinburghEdinburghUnited Kingdom
| | - Simona Bertoli
- International Center for the Assessment of Nutritional Status (ICANS), Department of Food, Environmental and Nutritional Sciences (DeFENS)University of MilanMilanItaly
| | - Simon H. Parson
- Euan MacDonald Centre for Motor Neurone Disease ResearchUniversity of EdinburghEdinburghUnited Kingdom
- Institute of Medical SciencesUniversity of AberdeenAberdeenUnited Kingdom
| | - Rashmi Kothary
- Regenerative Medicine ProgramOttawa Hospital Research InstituteOttawaOntarioCanada
- Department of Cellular and Molecular MedicineUniversity of OttawaOttawaOntarioCanada
- Centre for Neuromuscular DiseaseUniversity of OttawaOttawaOntarioCanadaK1H 8M5
- Department of MedicineUniversity of OttawaOttawaOntarioCanada
| |
Collapse
|
25
|
Shorrock HK, Gillingwater TH, Groen EJN. Overview of Current Drugs and Molecules in Development for Spinal Muscular Atrophy Therapy. Drugs 2019; 78:293-305. [PMID: 29380287 PMCID: PMC5829132 DOI: 10.1007/s40265-018-0868-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Spinal muscular atrophy (SMA) is a neurodegenerative disease primarily characterized by a loss of spinal motor neurons, leading to progressive paralysis and premature death in the most severe cases. SMA is caused by homozygous deletion of the survival motor neuron 1 (SMN1) gene, leading to low levels of SMN protein. However, a second SMN gene (SMN2) exists, which can be therapeutically targeted to increase SMN levels. This has recently led to the first disease-modifying therapy for SMA gaining formal approval from the US Food and Drug Administration (FDA) and European Medicines Agency (EMA). Spinraza (nusinersen) is a modified antisense oligonucleotide that targets the splicing of SMN2, leading to increased SMN protein levels, capable of improving clinical phenotypes in many patients. In addition to Spinraza, several other therapeutic approaches are currently in various stages of clinical development. These include SMN-dependent small molecule and gene therapy approaches along with SMN-independent strategies, such as general neuroprotective factors and muscle strength-enhancing compounds. For each therapy, we provide detailed information on clinical trial design and pharmacological/safety data where available. Previous clinical studies are also discussed to provide context on SMA clinical trial development and the insights these provided for the design of current studies.
Collapse
Affiliation(s)
- Hannah K Shorrock
- Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Hugh Robson Building, 15 George Square, Edinburgh, EH8 9XD, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Hugh Robson Building, 15 George Square, Edinburgh, EH8 9XD, UK
| | - Thomas H Gillingwater
- Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Hugh Robson Building, 15 George Square, Edinburgh, EH8 9XD, UK.,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Hugh Robson Building, 15 George Square, Edinburgh, EH8 9XD, UK
| | - Ewout J N Groen
- Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Hugh Robson Building, 15 George Square, Edinburgh, EH8 9XD, UK. .,Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Hugh Robson Building, 15 George Square, Edinburgh, EH8 9XD, UK.
| |
Collapse
|
26
|
Walter LM, Koch CE, Betts CA, Ahlskog N, Meijboom KE, van Westering TLE, Hazell G, Bhomra A, Claus P, Oster H, Wood MJA, Bowerman M. Light modulation ameliorates expression of circadian genes and disease progression in spinal muscular atrophy mice. Hum Mol Genet 2018; 27:3582-3597. [PMID: 29982483 PMCID: PMC6168969 DOI: 10.1093/hmg/ddy249] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 05/31/2018] [Accepted: 06/29/2018] [Indexed: 12/21/2022] Open
Abstract
Physiology and behaviour are critically dependent on circadian regulation via a core set of clock genes, dysregulation of which leads to metabolic and sleep disturbances. Metabolic and sleep perturbations occur in spinal muscular atrophy (SMA), a neuromuscular disorder caused by loss of the survival motor neuron (SMN) protein and characterized by motor neuron loss and muscle atrophy. We therefore investigated the expression of circadian rhythm genes in various metabolic tissues and spinal cord of the Taiwanese Smn-/-;SMN2 SMA animal model. We demonstrate a dysregulated expression of the core clock genes (clock, ARNTL/Bmal1, Cry1/2, Per1/2) and clock output genes (Nr1d1 and Dbp) in SMA tissues during disease progression. We also uncover an age- and tissue-dependent diurnal expression of the Smn gene. Importantly, we observe molecular and phenotypic corrections in SMA mice following direct light modulation. Our study identifies a key relationship between an SMA pathology and peripheral core clock gene dysregulation, highlights the influence of SMN on peripheral circadian regulation and metabolism and has significant implications for the development of peripheral therapeutic approaches and clinical care management of SMA patients.
Collapse
Affiliation(s)
- Lisa M Walter
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany
| | | | - Corinne A Betts
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Nina Ahlskog
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Katharina E Meijboom
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | | | - Gareth Hazell
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Amarjit Bhomra
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Peter Claus
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany
| | - Henrik Oster
- Institute of Neurobiology, University of Lübeck, Lübeck, Germany
| | - Matthew J A Wood
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Melissa Bowerman
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- Current affiliations: School of Medicine, Keele University, Staffordshire, UK
- Institute for Science and Technology in Medicine, Stoke-on-Trent, UK
- Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, UK
| |
Collapse
|
27
|
Myoepithelial cell-driven acini contraction in response to oxytocin receptor stimulation is impaired in lacrimal glands of Sjögren's syndrome animal models. Sci Rep 2018; 8:9919. [PMID: 29967327 PMCID: PMC6028591 DOI: 10.1038/s41598-018-28227-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 06/19/2018] [Indexed: 02/08/2023] Open
Abstract
The purpose of the present studies was to investigate the impact of chronic inflammation of the lacrimal gland, as occurs in Sjögren’s syndrome, on the morphology and function of myoepithelial cells (MECs). In spite of the importance of MECs for lacrimal gland function, the effect of inflammation on MECs has not been well defined. We studied changes in MEC structure and function in two animal models of aqueous deficient dry eye, NOD and MRL/lpr mice. We found a statistically significant reduction in the size of MECs in diseased compared to control lacrimal glands. We also found that oxytocin receptor was highly expressed in MECs of mouse and human lacrimal glands and that its expression was strongly reduced in diseased glands. Furthermore, we found a significant decrease in the amount of two MEC contractile proteins, α-smooth muscle actin (SMA) and calponin. Finally, oxytocin-mediated contraction was impaired in lacrimal gland acini from diseased glands. We conclude that chronic inflammation of the lacrimal gland leads to a substantial thinning of MECs, down-regulation of contractile proteins and oxytocin receptor expression, and therefore impaired acini contraction. This is the first study highlighting the role of oxytocin mediated MEC contraction on lacrimal gland function.
Collapse
|
28
|
Maxwell GK, Szunyogova E, Shorrock HK, Gillingwater TH, Parson SH. Developmental and degenerative cardiac defects in the Taiwanese mouse model of severe spinal muscular atrophy. J Anat 2018; 232:965-978. [PMID: 29473159 PMCID: PMC5978979 DOI: 10.1111/joa.12793] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/17/2018] [Indexed: 12/31/2022] Open
Abstract
Spinal muscular atrophy (SMA), an autosomal recessive disease caused by a decrease in levels of the survival motor neuron (SMN) protein, is the most common genetic cause of infant mortality. Although neuromuscular pathology is the most severe feature of SMA, other organs and tissues, including the heart, are also known to be affected in both patients and animal models. Here, we provide new insights into changes occurring in the heart, predominantly at pre- and early symptomatic ages, in the Taiwanese mouse model of severe SMA. Thinning of the interventricular septum and dilation of the ventricles occurred at pre- and early symptomatic ages. However, the left ventricular wall was significantly thinner in SMA mice from birth, occurring prior to any overt neuromuscular symptoms. Alterations in collagen IV protein from birth indicated changes to the basement membrane and contributed to the abnormal arrangement of cardiomyocytes in SMA hearts. This raises the possibility that developmental defects, occurring prenatally, may contribute to cardiac pathology in SMA. In addition, cardiomyocytes in SMA hearts exhibited oxidative stress at pre-symptomatic ages and increased apoptosis during early symptomatic stages of disease. Heart microvasculature was similarly decreased at an early symptomatic age, likely contributing to the oxidative stress and apoptosis phenotypes observed. Finally, an increased incidence of blood retention in SMA hearts post-fixation suggests the likelihood of functional defects, resulting in blood pooling. These pathologies mirror dilated cardiomyopathy, with clear consequences for heart function that would likely contribute to potential heart failure. Our findings add significant additional experimental evidence in support of the requirement to develop systemic therapies for SMA capable of treating non-neuromuscular pathologies.
Collapse
Affiliation(s)
| | - Eva Szunyogova
- Institute for Medical ScienceUniversity of AberdeenAberdeenUK
- Euan MacDonald Centre for Motor Neurone Disease ResearchUniversity of EdinburghEdinburghUK
| | - Hannah K. Shorrock
- Euan MacDonald Centre for Motor Neurone Disease ResearchUniversity of EdinburghEdinburghUK
- Edinburgh Medical School: Biomedical SciencesUniversity of EdinburghEdinburghUK
| | - Thomas H. Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease ResearchUniversity of EdinburghEdinburghUK
- Edinburgh Medical School: Biomedical SciencesUniversity of EdinburghEdinburghUK
| | - Simon H. Parson
- Institute for Medical ScienceUniversity of AberdeenAberdeenUK
- Euan MacDonald Centre for Motor Neurone Disease ResearchUniversity of EdinburghEdinburghUK
| |
Collapse
|
29
|
Walter LM, Deguise MO, Meijboom KE, Betts CA, Ahlskog N, van Westering TLE, Hazell G, McFall E, Kordala A, Hammond SM, Abendroth F, Murray LM, Shorrock HK, Prosdocimo DA, Haldar SM, Jain MK, Gillingwater TH, Claus P, Kothary R, Wood MJA, Bowerman M. Interventions Targeting Glucocorticoid-Krüppel-like Factor 15-Branched-Chain Amino Acid Signaling Improve Disease Phenotypes in Spinal Muscular Atrophy Mice. EBioMedicine 2018; 31:226-242. [PMID: 29735415 PMCID: PMC6013932 DOI: 10.1016/j.ebiom.2018.04.024] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 04/15/2018] [Accepted: 04/26/2018] [Indexed: 01/01/2023] Open
Abstract
The circadian glucocorticoid-Krüppel-like factor 15-branched-chain amino acid (GC-KLF15-BCAA) signaling pathway is a key regulatory axis in muscle, whose imbalance has wide-reaching effects on metabolic homeostasis. Spinal muscular atrophy (SMA) is a neuromuscular disorder also characterized by intrinsic muscle pathologies, metabolic abnormalities and disrupted sleep patterns, which can influence or be influenced by circadian regulatory networks that control behavioral and metabolic rhythms. We therefore set out to investigate the contribution of the GC-KLF15-BCAA pathway in SMA pathophysiology of Taiwanese Smn−/−;SMN2 and Smn2B/− mouse models. We thus uncover substantial dysregulation of GC-KLF15-BCAA diurnal rhythmicity in serum, skeletal muscle and metabolic tissues of SMA mice. Importantly, modulating the components of the GC-KLF15-BCAA pathway via pharmacological (prednisolone), genetic (muscle-specific Klf15 overexpression) and dietary (BCAA supplementation) interventions significantly improves disease phenotypes in SMA mice. Our study highlights the GC-KLF15-BCAA pathway as a contributor to SMA pathogenesis and provides several treatment avenues to alleviate peripheral manifestations of the disease. The therapeutic potential of targeting metabolic perturbations by diet and commercially available drugs could have a broader implementation across other neuromuscular and metabolic disorders characterized by altered GC-KLF15-BCAA signaling. SMA is a neuromuscular disease characterized by motoneuron loss, muscle abnormalities and metabolic perturbations. The regulatory GC-KLF15-BCAA pathway is dysregulated in serum and skeletal muscle of SMA mice during disease progression. Modulating GC-KLF15-BCAA signaling by pharmacological, dietary and genetic interventions improves phenotype of SMA mice.
Spinal muscular atrophy (SMA) is a devastating and debilitating childhood genetic disease. Although nerve cells are mainly affected, muscle is also severely impacted. The normal communication between the glucocorticoid (GC) hormone, the protein KLF15 and the dietary branched-chain amino acids (BCAAs) maintains muscle and whole-body health. In this study, we identified an abnormal activity of GC-KLF15- BCAA in blood and muscle of SMA mice. Importantly, targeting GC-KLF15-BCAA activity with an existing drug or a specific diet improved disease progression in SMA mice. Our research uncovers GCs, KLF15 and BCAAs as therapeutic targets to ameliorate SMA muscle and whole-body health.
Collapse
Affiliation(s)
- Lisa M Walter
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany; Center of Systems Neuroscience, Hannover, Germany
| | - Marc-Olivier Deguise
- Ottawa Hospital Research Institute, Regenerative Medicine Program, Ottawa, ON, Canada; Department of Medicine and Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Katharina E Meijboom
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Corinne A Betts
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Nina Ahlskog
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Tirsa L E van Westering
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Gareth Hazell
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Emily McFall
- Ottawa Hospital Research Institute, Regenerative Medicine Program, Ottawa, ON, Canada; Department of Medicine and Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Anna Kordala
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Suzan M Hammond
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Frank Abendroth
- Medical Research Council, Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Lyndsay M Murray
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom; Centre for Integrative Physiology, University of Edinburgh, Edinburgh, United Kingdom
| | - Hannah K Shorrock
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom; Centre for Integrative Physiology, University of Edinburgh, Edinburgh, United Kingdom
| | - Domenick A Prosdocimo
- Case Cardiovascular Research Institute, Case Western Reserve University School of Medicine, University Hospitals Case Medical Center, Cleveland, OH, USA
| | - Saptarsi M Haldar
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA, USA; Department of Medicine, Division of Cardiology University of California, San Francisco, CA, USA
| | - Mukesh K Jain
- Case Cardiovascular Research Institute, Case Western Reserve University School of Medicine, University Hospitals Case Medical Center, Cleveland, OH, USA
| | - Thomas H Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh, Edinburgh, United Kingdom; Centre for Integrative Physiology, University of Edinburgh, Edinburgh, United Kingdom
| | - Peter Claus
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Germany; Center of Systems Neuroscience, Hannover, Germany
| | - Rashmi Kothary
- Ottawa Hospital Research Institute, Regenerative Medicine Program, Ottawa, ON, Canada; Department of Medicine and Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Matthew J A Wood
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Melissa Bowerman
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom.
| |
Collapse
|
30
|
Bowerman M, Becker CG, Yáñez-Muñoz RJ, Ning K, Wood MJA, Gillingwater TH, Talbot K. Therapeutic strategies for spinal muscular atrophy: SMN and beyond. Dis Model Mech 2018; 10:943-954. [PMID: 28768735 PMCID: PMC5560066 DOI: 10.1242/dmm.030148] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Spinal muscular atrophy (SMA) is a devastating neuromuscular disorder characterized by loss of motor neurons and muscle atrophy, generally presenting in childhood. SMA is caused by low levels of the survival motor neuron protein (SMN) due to inactivating mutations in the encoding gene SMN1. A second duplicated gene, SMN2, produces very little but sufficient functional protein for survival. Therapeutic strategies to increase SMN are in clinical trials, and the first SMN2-directed antisense oligonucleotide (ASO) therapy has recently been licensed. However, several factors suggest that complementary strategies may be needed for the long-term maintenance of neuromuscular and other functions in SMA patients. Pre-clinical SMA models demonstrate that the requirement for SMN protein is highest when the structural connections of the neuromuscular system are being established, from late fetal life throughout infancy. Augmenting SMN may not address the slow neurodegenerative process underlying progressive functional decline beyond childhood in less severe types of SMA. Furthermore, individuals receiving SMN-based treatments may be vulnerable to delayed symptoms if rescue of the neuromuscular system is incomplete. Finally, a large number of older patients living with SMA do not fulfill the present criteria for inclusion in gene therapy and ASO clinical trials, and may not benefit from SMN-inducing treatments. Therefore, a comprehensive whole-lifespan approach to SMA therapy is required that includes both SMN-dependent and SMN-independent strategies that treat the CNS and periphery. Here, we review the range of non-SMN pathways implicated in SMA pathophysiology and discuss how various model systems can serve as valuable tools for SMA drug discovery. Summary: Translational research for spinal muscular atrophy (SMA) should address the development of non-CNS and survival motor neuron (SMN)-independent therapeutic approaches to complement and enhance the benefits of CNS-directed and SMN-dependent therapies.
Collapse
Affiliation(s)
- Melissa Bowerman
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX1 3QX, UK
| | - Catherina G Becker
- Euan MacDonald Centre for Motor Neurone Disease Research and Centre for Neuroregeneration, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Rafael J Yáñez-Muñoz
- AGCTlab.org, Centre for Biomedical Sciences, School of Biological Sciences, Royal Holloway, University of London, Egham Hill, Egham, Surrey TW20 0EX, UK
| | - Ke Ning
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield S10 2HQ, UK
| | - Matthew J A Wood
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX1 3QX, UK
| | - Thomas H Gillingwater
- Euan MacDonald Centre for Motor Neurone Disease Research and Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Kevin Talbot
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | | |
Collapse
|
31
|
Groen EJN, Talbot K, Gillingwater TH. Advances in therapy for spinal muscular atrophy: promises and challenges. Nat Rev Neurol 2018; 14:214-224. [PMID: 29422644 DOI: 10.1038/nrneurol.2018.4] [Citation(s) in RCA: 150] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Spinal muscular atrophy (SMA) is a devastating motor neuron disease that predominantly affects children and represents the most common cause of hereditary infant mortality. The condition results from deleterious variants in SMN1, which lead to depletion of the survival motor neuron protein (SMN). Now, 20 years after the discovery of this genetic defect, a major milestone in SMA and motor neuron disease research has been reached with the approval of the first disease-modifying therapy for SMA by US and European authorities - the antisense oligonucleotide nusinersen. At the same time, promising data from early-stage clinical trials of SMN1 gene therapy have indicated that additional therapeutic options are likely to emerge for patients with SMA in the near future. However, the approval of nusinersen has generated a number of immediate and substantial medical, ethical and financial implications that have the potential to resonate beyond the specific treatment of SMA. Here, we provide an overview of the rapidly evolving therapeutic landscape for SMA, highlighting current achievements and future opportunities. We also discuss how these developments are providing important lessons for the emerging second generation of combinatorial ('SMN-plus') therapies that are likely to be required to generate robust treatments that are effective across a patient's lifespan.
Collapse
Affiliation(s)
- Ewout J N Groen
- Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
| | - Kevin Talbot
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
| | - Thomas H Gillingwater
- Edinburgh Medical School: Biomedical Sciences, University of Edinburgh, Edinburgh, UK.,Euan MacDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh, UK
| |
Collapse
|
32
|
Bowerman M, Murray LM, Scamps F, Schneider BL, Kothary R, Raoul C. Pathogenic commonalities between spinal muscular atrophy and amyotrophic lateral sclerosis: Converging roads to therapeutic development. Eur J Med Genet 2017; 61:685-698. [PMID: 29313812 DOI: 10.1016/j.ejmg.2017.12.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 10/04/2017] [Accepted: 12/03/2017] [Indexed: 12/12/2022]
Abstract
Spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS) are the two most common motoneuron disorders, which share typical pathological hallmarks while remaining genetically distinct. Indeed, SMA is caused by deletions or mutations in the survival motor neuron 1 (SMN1) gene whilst ALS, albeit being mostly sporadic, can also be caused by mutations within genes, including superoxide dismutase 1 (SOD1), Fused in Sarcoma (FUS), TAR DNA-binding protein 43 (TDP-43) and chromosome 9 open reading frame 72 (C9ORF72). However, it has come to light that these two diseases may be more interlinked than previously thought. Indeed, it has recently been found that FUS directly interacts with an Smn-containing complex, mutant SOD1 perturbs Smn localization, Smn depletion aggravates disease progression of ALS mice, overexpression of SMN in ALS mice significantly improves their phenotype and lifespan, and duplications of SMN1 have been linked to sporadic ALS. Beyond genetic interactions, accumulating evidence further suggests that both diseases share common pathological identities such as intrinsic muscle defects, neuroinflammation, immune organ dysfunction, metabolic perturbations, defects in neuron excitability and selective motoneuron vulnerability. Identifying common molecular effectors that mediate shared pathologies in SMA and ALS would allow for the development of therapeutic strategies and targeted gene therapies that could potentially alleviate symptoms and be equally beneficial in both disorders. In the present review, we will examine our current knowledge of pathogenic commonalities between SMA and ALS, and discuss how furthering this understanding can lead to the establishment of novel therapeutic approaches with wide-reaching impact on multiple motoneuron diseases.
Collapse
Affiliation(s)
- Melissa Bowerman
- School of Medicine, Keele University, Staffordshire, United Kingdom; Institute for Science and Technology in Medicine, Stoke-on-Trent, United Kingdom; Wolfson Centre for Inherited Neuromuscular Disease, RJAH Orthopaedic Hospital, Oswestry, United Kingdom
| | - Lyndsay M Murray
- Euan McDonald Centre for Motor Neuron Disease Research and Centre for Integrative Physiology, University of Edinburgh, Edinburgh, United Kingdom
| | - Frédérique Scamps
- The Institute for Neurosciences of Montpellier, Inserm UMR1051, Univ Montpellier, Saint Eloi Hospital, Montpellier, France
| | - Bernard L Schneider
- Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Rashmi Kothary
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, Canada; Departments of Medicine and Cellular and Molecular Medicine, University of Ottawa, Ottawa, Canada
| | - Cédric Raoul
- The Institute for Neurosciences of Montpellier, Inserm UMR1051, Univ Montpellier, Saint Eloi Hospital, Montpellier, France.
| |
Collapse
|
33
|
Deguise M, Kothary R. New insights into SMA pathogenesis: immune dysfunction and neuroinflammation. Ann Clin Transl Neurol 2017; 4:522-530. [PMID: 28695153 PMCID: PMC5497530 DOI: 10.1002/acn3.423] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 04/25/2017] [Indexed: 12/13/2022] Open
Abstract
Spinal muscular atrophy (SMA) is a neuromuscular disorder characterized by motor neuron degeneration, although defects in multiple cell types and tissues have also been implicated. Three independent laboratories recently identified immune organ defects in SMA. We therefore propose a novel pathogenic mechanism contributory to SMA, resulting in higher susceptibility to infection and exacerbated disease progression caused by neuroinflammation. Overall, compromised immune function could significantly affect survival and quality of life of SMA patients. We highlight the recent findings in immune organ defects, their potential consequences on patients, our understanding of neuroinflammation in SMA, and new research hypotheses in SMA pathogenesis.
Collapse
Affiliation(s)
- Marc‐Olivier Deguise
- Regenerative Medicine ProgramOttawa Hospital Research InstituteOttawaOntarioK1H 8L6Canada
- Department of Cellular and Molecular MedicineUniversity of OttawaOttawaOntarioK1H 8M5Canada
- Centre for Neuromuscular DiseaseUniversity of OttawaOttawaOntarioK1H 8M5Canada
| | - Rashmi Kothary
- Regenerative Medicine ProgramOttawa Hospital Research InstituteOttawaOntarioK1H 8L6Canada
- Department of Cellular and Molecular MedicineUniversity of OttawaOttawaOntarioK1H 8M5Canada
- Centre for Neuromuscular DiseaseUniversity of OttawaOttawaOntarioK1H 8M5Canada
- Department of MedicineUniversity of OttawaOttawaOntarioK1H 8M5Canada
| |
Collapse
|