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Krishna S, Piepho AB, Lake DM, Cumby LR, Lortz KK, Lowe J, Chamberlain JS, Rafael-Fortney JA. Gene therapy delivered micro-dystrophins co-localize with transgenic utrophin in dystrophic skeletal muscle fibers. Neuromuscul Disord 2024; 36:1-5. [PMID: 38301403 DOI: 10.1016/j.nmd.2024.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 01/11/2024] [Indexed: 02/03/2024]
Abstract
Duchenne muscular dystrophy (DMD) is a devastating muscle disease caused by the absence of functional dystrophin. There are multiple ongoing clinical trials for DMD that are testing gene therapy treatments consisting of adeno-associated viral (AAV) vectors carrying miniaturized versions of dystrophin optimized for function, termed micro-dystrophins (μDys). Utrophin, the fetal homolog of dystrophin, has repeatedly been reported to be upregulated in human DMD muscle as a compensatory mechanism, but whether µDys displaces full-length utrophin is unknown. In this study, dystrophin/utrophin-deficient mice with transgenic overexpression of full-length utrophin in skeletal muscles were systemically administered low doses of either AAV6-CK8e-Hinge3-µDys (μDysH3) or AAV6-CK8e-μDys5 (μDys5). We used immunofluorescence to qualitatively assess the localization of μDys with transgenic utrophin and neuronal nitric oxide synthase (nNOS) in quadriceps muscles. μDys protein resulting from both gene therapies co-localized at myofiber membranes with transgenic utrophin. We also confirmed the sarcolemmal co-localization of nNOS with μDys5, but not with transgenic utrophin expression or μDysH3. Transgenic utrophin expression and μDys proteins produced from both therapies stabilize the dystrophin-glycoprotein complex as observed by sarcolemmal localization of β-dystroglycan. This study suggests that µDys gene therapy will likely not inhibit any endogenous compensation by utrophin in DMD muscle.
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Affiliation(s)
- Swathy Krishna
- Department of Physiology & Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Arden B Piepho
- Department of Physiology & Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Dana M Lake
- Department of Physiology & Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Laurel R Cumby
- Department of Physiology & Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Kaelyn K Lortz
- Department of Physiology & Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Jeovanna Lowe
- Department of Physiology & Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Jeffrey S Chamberlain
- Department of Neurology and Sen. Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Washington, Seattle, WA 98109, USA
| | - Jill A Rafael-Fortney
- Department of Physiology & Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA.
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Szwec S, Kapłucha Z, Chamberlain JS, Konieczny P. Dystrophin- and Utrophin-Based Therapeutic Approaches for Treatment of Duchenne Muscular Dystrophy: A Comparative Review. BioDrugs 2024; 38:95-119. [PMID: 37917377 PMCID: PMC10789850 DOI: 10.1007/s40259-023-00632-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/10/2023] [Indexed: 11/04/2023]
Abstract
Duchenne muscular dystrophy is a devastating disease that leads to progressive muscle loss and premature death. While medical management focuses mostly on symptomatic treatment, decades of research have resulted in first therapeutics able to restore the affected reading frame of dystrophin transcripts or induce synthesis of a truncated dystrophin protein from a vector, with other strategies based on gene therapy and cell signaling in preclinical or clinical development. Nevertheless, recent reports show that potentially therapeutic dystrophins can be immunogenic in patients. This raises the question of whether a dystrophin paralog, utrophin, could be a more suitable therapeutic protein. Here, we compare dystrophin and utrophin amino acid sequences and structures, combining published data with our extended in silico analyses. We then discuss these results in the context of therapeutic approaches for Duchenne muscular dystrophy. Specifically, we focus on strategies based on delivery of micro-dystrophin and micro-utrophin genes with recombinant adeno-associated viral vectors, exon skipping of the mutated dystrophin pre-mRNAs, reading through termination codons with small molecules that mask premature stop codons, dystrophin gene repair by clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (CRISPR/Cas9)-mediated genetic engineering, and increasing utrophin levels. Our analyses highlight the importance of various dystrophin and utrophin domains in Duchenne muscular dystrophy treatment, providing insights into designing novel therapeutic compounds with improved efficacy and decreased immunoreactivity. While the necessary actin and β-dystroglycan binding sites are present in both proteins, important functional distinctions can be identified in these domains and some other parts of truncated dystrophins might need redesigning due to their potentially immunogenic qualities. Alternatively, therapies based on utrophins might provide a safer and more effective approach.
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Affiliation(s)
- Sylwia Szwec
- Institute of Human Biology and Evolution, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland
| | - Zuzanna Kapłucha
- Institute of Human Biology and Evolution, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland
| | - Jeffrey S Chamberlain
- Department of Neurology, University of Washington School of Medicine, Seattle, WA, 98109-8055, USA
- Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Washington School of Medicine, Seattle, WA, 98109-8055, USA
- Department of Biochemistry, University of Washington School of Medicine, Seattle, WA, 98109-8055, USA
- Department of Medicine, University of Washington School of Medicine, Seattle, WA, 98109-8055, USA
| | - Patryk Konieczny
- Institute of Human Biology and Evolution, Faculty of Biology, Adam Mickiewicz University, ul. Uniwersytetu Poznańskiego 6, 61-614, Poznań, Poland.
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3
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Wang L, Feng J, Feng X, Meng D, Zhao X, Wang J, Yu P, Xu GE, Hu M, Wang T, Lehmann HI, Li G, Sluijter JPG, Xiao J. Exercise-induced circular RNA circUtrn is required for cardiac physiological hypertrophy and prevents myocardial ischaemia-reperfusion injury. Cardiovasc Res 2023; 119:2638-2652. [PMID: 37897547 DOI: 10.1093/cvr/cvad161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 08/21/2023] [Accepted: 09/04/2023] [Indexed: 10/30/2023] Open
Abstract
AIMS Regular exercise training benefits cardiovascular health and effectively reduces the risk for cardiovascular disease. Circular RNAs (circRNAs) play important roles in cardiac pathophysiology. However, the role of circRNAs in response to exercise training and biological mechanisms responsible for exercise-induced cardiac protection remain largely unknown. METHODS AND RESULTS RNA sequencing was used to profile circRNA expression in adult mouse cardiomyocytes that were isolated from mice with or without exercise training. Exercise-induced circRNA circUtrn was significantly increased in swimming-trained adult mouse cardiomyocytes. In vivo, circUtrn was found to be required for exercise-induced physiological cardiac hypertrophy. circUtrn inhibition abolished the protective effects of exercise on myocardial ischaemia-reperfusion remodelling. circUtrn overexpression prevented myocardial ischaemia-reperfusion-induced acute injury and pathological cardiac remodelling. In vitro, overexpression of circUtrn promoted H9 human embryonic stem cell-induced cardiomyocyte growth and survival via protein phosphatase 5 (PP5). Mechanistically, circUtrn directly bound to PP5 and regulated the stability of PP5 in a ubiquitin-proteasome-dependent manner. Hypoxia-inducible factor 1α-dependent splicing factor SF3B1 acted as an upstream regulator of circUtrn in cardiomyocytes. CONCLUSION The circRNA circUtrn is upregulated upon exercise training in the heart. Overexpression of circUtrn can prevent myocardial I/R-induced injury and pathological cardiac remodelling.
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Affiliation(s)
- Lijun Wang
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Life Science, Shanghai University, 881 Yonghe Road, Chongchuan District, Nantong 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, 333 Nanchen Road, Baoshan District, Shanghai 200444, China
| | - Jingyi Feng
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Life Science, Shanghai University, 881 Yonghe Road, Chongchuan District, Nantong 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, 333 Nanchen Road, Baoshan District, Shanghai 200444, China
| | - Xing Feng
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Life Science, Shanghai University, 881 Yonghe Road, Chongchuan District, Nantong 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, 333 Nanchen Road, Baoshan District, Shanghai 200444, China
| | - Danni Meng
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Life Science, Shanghai University, 881 Yonghe Road, Chongchuan District, Nantong 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, 333 Nanchen Road, Baoshan District, Shanghai 200444, China
| | - Xuan Zhao
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Life Science, Shanghai University, 881 Yonghe Road, Chongchuan District, Nantong 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, 333 Nanchen Road, Baoshan District, Shanghai 200444, China
| | - Jiaqi Wang
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Life Science, Shanghai University, 881 Yonghe Road, Chongchuan District, Nantong 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, 333 Nanchen Road, Baoshan District, Shanghai 200444, China
| | - Pujiao Yu
- Department of Cardiology, Shanghai Tongji hospital, Tongji University School of Medicine, 389 Xincun Road, Putuo District, Shanghai 200065, China
| | - Gui-E Xu
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Life Science, Shanghai University, 881 Yonghe Road, Chongchuan District, Nantong 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, 333 Nanchen Road, Baoshan District, Shanghai 200444, China
| | - Meiyu Hu
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Life Science, Shanghai University, 881 Yonghe Road, Chongchuan District, Nantong 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, 333 Nanchen Road, Baoshan District, Shanghai 200444, China
| | - Tianhui Wang
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Life Science, Shanghai University, 881 Yonghe Road, Chongchuan District, Nantong 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, 333 Nanchen Road, Baoshan District, Shanghai 200444, China
| | - H Immo Lehmann
- Cardiovascular Division, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Guoping Li
- Cardiovascular Division, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Joost P G Sluijter
- Department of Cardiology, Laboratory of Experimental Cardiology, University Medical Center Utrecht, Utrecht 3508GA, The Netherlands
- Regenerative Medicine Center, Circulatory Health Laboratory, University Medical Center Utrecht, University Utrecht, Utrecht 3508GA, The Netherlands
| | - Junjie Xiao
- Institute of Geriatrics, Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Life Science, Shanghai University, 881 Yonghe Road, Chongchuan District, Nantong 226011, China
- Cardiac Regeneration and Ageing Lab, Institute of Cardiovascular Sciences, Shanghai Engineering Research Center of Organ Repair, School of Medicine, Shanghai University, 333 Nanchen Road, Baoshan District, Shanghai 200444, China
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Liu M, Gong C, Shen X, Jiang Y, Xu Y, Zhong W, Chen Y, Dong N, Liao J, Yin N. Mitochondrial dynamics-related genes DRP1 and OPA1 contributes to early diagnosis of cognitive impairment in diabetes. BMC Geriatr 2023; 23:484. [PMID: 37563583 PMCID: PMC10416428 DOI: 10.1186/s12877-023-04156-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 07/05/2023] [Indexed: 08/12/2023] Open
Abstract
BACKGROUND AND AIM DRP1 and OPA1 play important roles in mitochondrial fusion and fission. However, the role of DRP1 and OPA1 amplification in mitochondrial cognitive impairment has not been reported. This study aimed to investigate the relationship between DRP1 and OPA1 and the risk of cognitive impairment. METHODS In this study, 45 elderly patients with diabetes admitted to the Lianyungang Second People's Hospital from September 2020 to January 2021 were included. The patients were divided into normal group, mild cognitive impairment group and dementia group by using MMSE score, and the clinical characteristics of the three groups were compared. The amplification multiples of the two genes' DNA were calculated by ΔΔCT and defined as 2- K. Spearman rank correlation was used to analyze the correlation between the DNA amplification multiples of patients' DRP1 and OPA1 and AD8 and MoCA scores. The sensitivity and specificity of DNA amplification multiples of DRP1 and OPA1 to predict clinical outcomes of diabetic cognitive impairment were evaluated using Receiver operator characteristic (ROC) curves. Multiple logistic regression was used to evaluate the relationship between DNA amplification factor of DRP1 and OPA1 and cognitive function. RESULTS DRP1(2- K) and OPA1(2- K) significantly increased and decreased in dementia and MCI groups compared with the normal group (P ≤ 0.001). The DNA amplification factor of DRP1 was positively correlated with AD8 score and negatively correlated with MoCA score (P < 0.001). The DNA amplification factor of OPA1 was positively correlated with the MoCA score (P = 0.0002). Analysis of ROCs showed that the DNA amplification factor of OPA1 had a higher predictive value for dementia (P < 0.0001), and that it had a higher predictive value when used in combination with DRP1. Multiple logistic regression results showed that increased DNA amplification in DRP1 was associated with increased risk of dementia (OR 1.149;95%CI,1.035-1.275), and increased DNA amplification in OPA1 was associated with decreased risk of MCI (OR 0.004;95%CI,0.000-0.251) and dementia (OR 0.000;95%CI,0.000-0.134). CONCLUSION DNA amplification multiples of DRP1 and OPA1 are associated with the risk of dementia in elderly patients and may serve as potential biomarkers.
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Affiliation(s)
- Mengqian Liu
- Department of Geriatrics, Lianyungang Hospital Affifiliated to Jiangsu University (Lianyungang Second People's Hospital), Lianyungang, China
| | - Chen Gong
- Department of Geriatrics, Lianyungang Hospital Affifiliated to Jiangsu University (Lianyungang Second People's Hospital), Lianyungang, China
| | - Xiaozhu Shen
- Department of Geriatrics, Lianyungang Hospital Affifiliated to Jiangsu University (Lianyungang Second People's Hospital), Lianyungang, China.
| | - Yi Jiang
- Department of Geriatrics, Lianyungang Hospital Affifiliated to Jiangsu University (Lianyungang Second People's Hospital), Lianyungang, China
- Department of Geriatrics, Bengbu Medical College Clinical College of Lianyungang Second People's Hospital, Lianyungang, China
| | - Yiwen Xu
- Department of Geriatrics, Lianyungang Hospital Affifiliated to Jiangsu University (Lianyungang Second People's Hospital), Lianyungang, China
| | - Wen Zhong
- Department of Geriatrics, Lianyungang Hospital Affifiliated to Jiangsu University (Lianyungang Second People's Hospital), Lianyungang, China
| | - Yujiao Chen
- Department of Laboratory Medicine, Lianyungang Second People's Hospital, Lianyungang, China
| | - Nan Dong
- Department of Neurology, Suzhou Industrial Park Xinghai Hospital, Suzhou, China
| | - Jingxian Liao
- Department of Geriatrics, Lianyungang Hospital Affifiliated to Jiangsu University (Lianyungang Second People's Hospital), Lianyungang, China
| | - Ning Yin
- Department of Geriatrics, Lianyungang Hospital Affifiliated to Jiangsu University (Lianyungang Second People's Hospital), Lianyungang, China.
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5
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Gleneadie HJ, Fernandez-Ruiz B, Sardini A, Van de Pette M, Dimond A, Prinjha RK, McGinty J, French PMW, Bagci H, Merkenschlager M, Fisher AG. Endogenous bioluminescent reporters reveal a sustained increase in utrophin gene expression upon EZH2 and ERK1/2 inhibition. Commun Biol 2023; 6:318. [PMID: 36966198 PMCID: PMC10039851 DOI: 10.1038/s42003-023-04666-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 03/06/2023] [Indexed: 03/27/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is an X-linked disorder caused by loss of function mutations in the dystrophin gene (Dmd), resulting in progressive muscle weakening. Here we modelled the longitudinal expression of endogenous Dmd, and its paralogue Utrn, in mice and in myoblasts by generating bespoke bioluminescent gene reporters. As utrophin can partially compensate for Dmd-deficiency, these reporters were used as tools to ask whether chromatin-modifying drugs can enhance Utrn expression in developing muscle. Myoblasts treated with different PRC2 inhibitors showed significant increases in Utrn transcripts and bioluminescent signals, and these responses were independently verified by conditional Ezh2 deletion. Inhibition of ERK1/2 signalling provoked an additional increase in Utrn expression that was also seen in Dmd-mutant cells, and maintained as myoblasts differentiate. These data reveal PRC2 and ERK1/2 to be negative regulators of Utrn expression and provide specialised molecular imaging tools to monitor utrophin expression as a therapeutic strategy for DMD.
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Affiliation(s)
- Hannah J Gleneadie
- Epigenetic Memory Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Beatriz Fernandez-Ruiz
- Epigenetic Memory Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Alessandro Sardini
- Whole Animal Physiology and Imaging Facility, MRC LMS, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Mathew Van de Pette
- Epigenetic Memory Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, Du Cane Road, London, W12 0NN, UK
- MRC Toxicology Unit, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Andrew Dimond
- Epigenetic Memory Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Rab K Prinjha
- Immunology and Epigenetics Research Unit, Research, GlaxoSmithKline, Gunnels Wood Road, Stevenage, Herts, SG1 2NY, UK
| | - James McGinty
- Photonics Group, Department of Physics, Blackett Laboratory, Imperial College London, London, SW7 2AZ, UK
| | - Paul M W French
- Photonics Group, Department of Physics, Blackett Laboratory, Imperial College London, London, SW7 2AZ, UK
| | - Hakan Bagci
- Lymphocyte Development Group, MRC LMS, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Matthias Merkenschlager
- Lymphocyte Development Group, MRC LMS, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Amanda G Fisher
- Epigenetic Memory Group, MRC London Institute of Medical Sciences (LMS), Imperial College London, Du Cane Road, London, W12 0NN, UK.
- Department of Biochemistry, University of Oxford, South Parks Road, OX1 3QU, Oxford, UK.
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Ramirez MP, Rajaganapathy S, Hagerty AR, Hua C, Baxter GC, Vavra J, Gordon WR, Muretta JM, Salapaka MV, Ervasti JM. Phosphorylation alters the mechanical stiffness of a model fragment of the dystrophin homologue utrophin. J Biol Chem 2023; 299:102847. [PMID: 36587764 PMCID: PMC9922815 DOI: 10.1016/j.jbc.2022.102847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/16/2022] [Accepted: 12/18/2022] [Indexed: 12/30/2022] Open
Abstract
Duchenne muscular dystrophy is a lethal muscle wasting disease caused by the absence of the protein dystrophin. Utrophin is a dystrophin homologue currently under investigation as a protein replacement therapy for Duchenne muscular dystrophy. Dystrophin is hypothesized to function as a molecular shock absorber that mechanically stabilizes the sarcolemma. While utrophin is homologous with dystrophin from a molecular and biochemical perspective, we have recently shown that full-length utrophin expressed in eukaryotic cells is stiffer than what has been reported for dystrophin fragments expressed in bacteria. In this study, we show that differences in expression system impact the mechanical stiffness of a model utrophin fragment encoding the N terminus through spectrin repeat 3 (UtrN-R3). We also demonstrate that UtrN-R3 expressed in eukaryotic cells was phosphorylated while bacterial UtrN-R3 was not detectably phosphorylated. Using atomic force microscopy, we show that phosphorylated UtrN-R3 exhibited significantly higher unfolding forces compared to unphosphorylated UtrN-R3 without altering its actin-binding activity. Consistent with the effect of phosphorylation on mechanical stiffness, mutating the phosphorylated serine residues on insect eukaryotic protein to alanine decreased its stiffness to levels not different from unphosphorylated bacterial protein. Taken together, our data suggest that the mechanical properties of utrophin may be tuned by phosphorylation, with the potential to improve its efficacy as a protein replacement therapy for dystrophinopathies.
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Affiliation(s)
- Maria Paz Ramirez
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Sivaraman Rajaganapathy
- Department of Electrical and Computer Engineering, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Anthony R Hagerty
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Cailong Hua
- Department of Electrical and Computer Engineering, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Gloria C Baxter
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Joseph Vavra
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Wendy R Gordon
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Joseph M Muretta
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Murti V Salapaka
- Department of Electrical and Computer Engineering, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - James M Ervasti
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota - Twin Cities, Minneapolis, MN, USA.
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7
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Kennedy TL, Dugdale HF. Cardiac and Skeletal Muscle Pathology in the D2/mdx Mouse Model and Caveats Associated with the Quantification of Utrophin. Methods Mol Biol 2023; 2587:55-66. [PMID: 36401024 DOI: 10.1007/978-1-0716-2772-3_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Duchenne muscular dystrophy (DMD) (the most common form of muscular dystrophy) is caused by a lack of dystrophin protein. Currently, although many therapeutic strategies are under investigation, there is no cure for DMD and unfortunately, patients succumb to respiratory and/or cardiac failure in their second or third decade of life. Preclinical work has focused on the mouse model C57BL/10ScSn-Dmdmdx/J (BL10/mdx), which does not exhibit a robust pathophenotype. More recently, the D2.B10-Dmdmdx/J (D2/mdx) mouse has been utilized, which presents a more severe pathology and therefore more closely mimics the human pathophenotype, particularly in the heart. Here, we outline important considerations when utilizing the D2/mdx model by highlighting the differences between these models in addition to describing histological and immunohistochemical methods utilized in Kennedy et al. (Mol Ther Methods Clin Dev 11:92-105, 2018) for both cardiac and skeletal muscle, which can quantify these differences. These considerations are particularly important when investigating treatment strategies that may be affected by regeneration; such is the case for upregulation of the dystrophin paralogue, utrophin.
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Affiliation(s)
- Tahnee L Kennedy
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Hannah F Dugdale
- Centre for Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, Guy's Campus, King's College London, London, UK.
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK.
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8
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Abstract
Duchenne muscular dystrophy (DMD) is a neuromuscular disease caused by mutations and deletions within the DMD gene, which result in a lack of dystrophin protein at the sarcolemma of skeletal muscle fibers. The absence of dystrophin fragilizes the sarcolemma and compromises its integrity during cycles of muscle contraction, which, progressively, leads to reductions in muscle mass and function. DMD is thus a progressive muscle-wasting disease that results in a loss of ambulation, cardiomyopathy , respiratory impairment, and death. Although there is presently no cure for DMD, recent advances have led to many promising treatments. One such approach entails increasing expression of a homologous protein to dystrophin, named utrophin A, which is endogenously expressed in both healthy and DMD muscle fibers. Upregulation of utrophin A all along the sarcolemma of DMD muscle fibers can, in part, compensate for the absence of dystrophin. Over the years, our laboratory has focused a significant portion of our efforts in identifying and characterizing drugs and small molecules for their ability to target utrophin A and cause its overexpression. As part of these efforts, we have recently developed a novel ELISA-based high-throughput drug screen, to identify FDA-approved drugs that increase the expression of utrophin A in muscle cells in culture as well as in dystrophic mice. Here, we describe our overall strategy to identify and characterize several FDA-approved drugs that upregulate utrophin A expression and provide details on all experimental approaches. Such strategy has the potential to lead to the rapid development of novel therapeutics for DMD.
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Affiliation(s)
- Christine Péladeau
- Department of Cellular and Molecular Medicine, and the Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Bernard J Jasmin
- Department of Cellular and Molecular Medicine, and the Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.
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9
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Lin BL, Shin JY, Jeffreys WP, Wang N, Lukban CA, Moorer MC, Velarde E, Hanselman OA, Kwon S, Kannan S, Riddle RC, Ward CW, Pullen SS, Filareto A, Kass DA. Pharmacological TRPC6 inhibition improves survival and muscle function in mice with Duchenne muscular dystrophy. JCI Insight 2022; 7:e158906. [PMID: 36099033 PMCID: PMC9675567 DOI: 10.1172/jci.insight.158906] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 08/26/2022] [Indexed: 11/17/2022] Open
Abstract
Gene mutations causing loss of dystrophin result in the severe muscle disease known as Duchenne muscular dystrophy (DMD). Despite efforts at genetic repair, DMD therapy remains largely palliative. Loss of dystrophin destabilizes the sarcolemmal membrane, inducing mechanosensitive cation channels to increase calcium entry and promote cell damage and, eventually, muscle dysfunction. One putative channel is transient receptor potential canonical 6 (TRPC6); we have shown that TRPC6 contributed to abnormal force and calcium stress-responses in cardiomyocytes from mice lacking dystrophin that were haplodeficient for utrophin (mdx/utrn+/- [HET] mice). Here, we show in both the HET mouse and the far more severe homozygous mdx/utrn-/- mouse that TRPC6 gene deletion or its selective pharmacologic inhibition (by BI 749327) prolonged survival 2- to 3-fold, improving skeletal and cardiac muscle and bone defects. Gene pathways reduced by BI 749327 treatment most prominently regulated fat metabolism and TGF-β1 signaling. These results support the testing of TRPC6 inhibitors in human trials for other diseases as a novel DMD therapy.
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Affiliation(s)
| | | | | | | | | | | | - Esteban Velarde
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland, USA
| | | | | | | | | | | | | | - Antonio Filareto
- Research Beyond Borders, Boehringer Ingelheim Pharmaceuticals, Ridgefield, Connecticut, USA
| | - David A. Kass
- Department of Cardiology
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University, Baltimore, Maryland, USA
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10
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Chatzopoulou M, Conole D, Emer E, Rowley JA, Willis NJ, Squire SE, Gill B, Brough S, Wilson FX, Wynne GM, Davies SG, Davies KE, Russell AJ. Structure-activity relationships of 2-pyrimidinecarbohydrazides as utrophin modulators for the potential treatment of Duchenne muscular dystrophy. Bioorg Med Chem 2022; 69:116812. [PMID: 35772287 DOI: 10.1016/j.bmc.2022.116812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/05/2022] [Accepted: 05/05/2022] [Indexed: 11/02/2022]
Abstract
A therapeutic approach that holds the potential to treat all Duchenne muscular dystrophy (DMD) patient populations is utrophin modulation. Ezutromid, a first generation utrophin modulator which was later found to act via antagonism of the arylhydrocarbon receptor, progressed to Phase 2 clinical trials. Although interim data showed target engagement and functional improvements, ezutromid ultimately failed to meet its clinical endpoints. We recently described the identification of a new class of hydrazide utrophin modulators which has a different mechanism of action to ezutromid. In this study we report our early optimisation studies on this hydrazide series. The new analogues had significantly improved potency in cell-based assays, increased sp3 character and reduced lipophilicity, which also improved their physicochemical properties. A representative new analogue combining these attributes increased utrophin protein in dystrophic mouse cells showing it can be used as a chemical tool to reveal new insights regarding utrophin upregulation as a strategy for DMD therapeutic intervention.
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Affiliation(s)
- Maria Chatzopoulou
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Daniel Conole
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Enrico Emer
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Jessica A Rowley
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Nicky J Willis
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Sarah E Squire
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sir Henry Wellcome Building of Gene Function, South Parks Road, Oxford OX1 3PT, UK
| | - Becky Gill
- Key Organics Ltd, Highfield Road Industrial Estate, Camelford, Cornwall PL32 9RA, UK
| | - Steve Brough
- Key Organics Ltd, Highfield Road Industrial Estate, Camelford, Cornwall PL32 9RA, UK
| | - Francis X Wilson
- Summit Therapeutics Plc, 136a Eastern Avenue, Milton Park, Abingdon, Oxfordshire OX14 4SB, UK
| | - Graham M Wynne
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Stephen G Davies
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Kay E Davies
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sir Henry Wellcome Building of Gene Function, South Parks Road, Oxford OX1 3PT, UK
| | - Angela J Russell
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK; Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3PQ, UK
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11
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Lin C, Han G, Jia L, Zhao Y, Song J, Ran N, Yokota T, Seow Y, Yin H. Cardio-respiratory and phenotypic rescue of dystrophin/utrophin-deficient mice by combination therapy. EMBO Rep 2022; 23:e53955. [PMID: 35393769 PMCID: PMC9171417 DOI: 10.15252/embr.202153955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 03/14/2022] [Accepted: 03/17/2022] [Indexed: 11/09/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a systemic progressive muscular disease caused by frame-disrupting mutations in the DMD gene. Although exon-skipping antisense oligonucleotides (AOs) are clinically approved and can correct DMD, insufficient muscle delivery limits efficacy. If AO activity can be enhanced by safe dietary supplements, clinical trials for efficacy can be undertaken rapidly to benefit patients. We showed previously that intravenous glycine enhanced phosphorodiamidate morpholino oligomer (PMO) delivery to peripheral muscles in mdx mice. Here, we demonstrate that the combination of oral glycine and metformin with intravenous PMO enhances PMO activity, dystrophin restoration, extends lifespan, and improves body-wide function and phenotypic rescue of dystrophin /utrophin double knock-out (DKO) mice without any overt adverse effects. The DKO mice treated with the combination without altering the approved administration protocol of PMO show improved cardio-respiratory and behavioral functions. Metformin and glycine individually are ineffective in DMD patients, but the combination of PMO with clinically-approved oral glycine and metformin might improve the efficacy of the treatment also in DMD patients. Our data suggest that this combination therapy might be an attractive therapy for DMD and potentially other muscle diseases requiring systemic treatment with AOs.
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Affiliation(s)
- Caorui Lin
- The Province and Ministry Co‐sponsored Collaborative Innovation Center for Medical EpigeneticsSchool of Medical Technology & School of Basic Medical SciencesTianjin Medical UniversityTianjinChina
| | - Gang Han
- The Province and Ministry Co‐sponsored Collaborative Innovation Center for Medical EpigeneticsSchool of Medical Technology & School of Basic Medical SciencesTianjin Medical UniversityTianjinChina
| | - Lulu Jia
- The Province and Ministry Co‐sponsored Collaborative Innovation Center for Medical EpigeneticsSchool of Medical Technology & School of Basic Medical SciencesTianjin Medical UniversityTianjinChina
| | - Yiwen Zhao
- The Province and Ministry Co‐sponsored Collaborative Innovation Center for Medical EpigeneticsSchool of Medical Technology & School of Basic Medical SciencesTianjin Medical UniversityTianjinChina
| | - Jun Song
- The Province and Ministry Co‐sponsored Collaborative Innovation Center for Medical EpigeneticsSchool of Medical Technology & School of Basic Medical SciencesTianjin Medical UniversityTianjinChina
| | - Ning Ran
- The Province and Ministry Co‐sponsored Collaborative Innovation Center for Medical EpigeneticsSchool of Medical Technology & School of Basic Medical SciencesTianjin Medical UniversityTianjinChina
| | - Toshifumi Yokota
- Department of Medical GeneticsFaculty of Medicine and DentistryUniversity of AlbertaEdmontonABCanada
| | - Yiqi Seow
- Institute of Bioengineering and BioimagingSingapore CitySingapore
- Institute of Molecular and Cell BiologySingapore CitySingapore
| | - HaiFang Yin
- The Province and Ministry Co‐sponsored Collaborative Innovation Center for Medical EpigeneticsSchool of Medical Technology & School of Basic Medical SciencesTianjin Medical UniversityTianjinChina
- Department of Clinical LaboratoryTianjin Medical University General HospitalTianjinChina
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12
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Mamsa H, Stark RL, Shin KM, Beedle AM, Crosbie RH. Sarcospan increases laminin-binding capacity of α-dystroglycan to ameliorate DMD independent of Galgt2. Hum Mol Genet 2022; 31:718-732. [PMID: 34581784 PMCID: PMC8895749 DOI: 10.1093/hmg/ddab276] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 08/27/2021] [Accepted: 09/13/2021] [Indexed: 11/14/2022] Open
Abstract
In Duchenne muscular dystrophy (DMD), mutations in dystrophin result in a loss of the dystrophin-glycoprotein complex (DGC) at the myofiber membrane, which functions to connect the extracellular matrix with the intracellular actin cytoskeleton. The dystroglycan subcomplex interacts with dystrophin and spans the sarcolemma where its extensive carbohydrates (matriglycan and CT2 glycan) directly interact with the extracellular matrix. In the current manuscript, we show that sarcospan overexpression enhances the laminin-binding capacity of dystroglycan in DMD muscle by increasing matriglycan glycosylation of α-dystroglycan. Furthermore, we find that this modification is not affected by loss of Galgt2, a glycotransferase, which catalyzes the CT2 glycan. Our findings reveal that the matriglycan carbohydrates, and not the CT2 glycan, are necessary for sarcospan-mediated amelioration of DMD. Overexpression of Galgt2 in the DMD mdx murine model prevents muscle pathology by increasing CT2 modified α-dystroglycan. Galgt2 also increases expression of utrophin, which compensates for the loss of dystrophin in DMD muscle. We found that combined loss of Galgt2 and dystrophin reduced utrophin expression; however, it did not interfere with sarcospan rescue of disease. These data reveal a partial dependence of sarcospan on Galgt2 for utrophin upregulation. In addition, sarcospan alters the cross-talk between the adhesion complexes by decreasing the association of integrin β1D with dystroglycan complexes. In conclusion, sarcospan functions to re-wire the cell to matrix connections by strengthening the cellular adhesion and signaling, which, in turn, increases the resilience of the myofiber membrane.
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Affiliation(s)
- Hafsa Mamsa
- Department of Integrative Biology & Physiology, University of California, Los Angeles 90095, USA
| | - Rachelle L Stark
- Department of Integrative Biology & Physiology, University of California, Los Angeles 90095, USA
| | - Kara M Shin
- Department of Integrative Biology & Physiology, University of California, Los Angeles 90095, USA
| | - Aaron M Beedle
- Department of Pharmaceutical Sciences, Binghamton University State University of New York, New York 13902, USA
| | - Rachelle H Crosbie
- Department of Integrative Biology & Physiology, University of California, Los Angeles 90095, USA
- Broad Stem Cell Institute, University of California, Los Angeles 90095, USA
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles 90095, USA
- Molecular Biology Institute, University of California, Los Angeles 90095, USA
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13
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Dort J, Orfi Z, Fabre P, Molina T, Conte TC, Greffard K, Pellerito O, Bilodeau JF, Dumont NA. Resolvin-D2 targets myogenic cells and improves muscle regeneration in Duchenne muscular dystrophy. Nat Commun 2021; 12:6264. [PMID: 34716330 PMCID: PMC8556273 DOI: 10.1038/s41467-021-26516-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 09/29/2021] [Indexed: 12/24/2022] Open
Abstract
Lack of dystrophin causes muscle degeneration, which is exacerbated by chronic inflammation and reduced regenerative capacity of muscle stem cells in Duchenne Muscular Dystrophy (DMD). To date, glucocorticoids remain the gold standard for the treatment of DMD. These drugs are able to slow down the progression of the disease and increase lifespan by dampening the chronic and excessive inflammatory process; however, they also have numerous harmful side effects that hamper their therapeutic potential. Here, we investigated Resolvin-D2 as a new therapeutic alternative having the potential to target multiple key features contributing to the disease progression. Our in vitro findings showed that Resolvin-D2 promotes the switch of macrophages toward their anti-inflammatory phenotype and increases their secretion of pro-myogenic factors. Moreover, Resolvin-D2 directly targets myogenic cells and promotes their differentiation and the expansion of the pool of myogenic progenitor cells leading to increased myogenesis. These effects are ablated when the receptor Gpr18 is knocked-out, knocked-down, or blocked by the pharmacological antagonist O-1918. Using different mouse models of DMD, we showed that Resolvin-D2 targets both inflammation and myogenesis leading to enhanced muscle function compared to glucocorticoids. Overall, this preclinical study has identified a new therapeutic approach that is more potent than the gold-standard treatment for DMD.
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Affiliation(s)
- Junio Dort
- CHU Sainte-Justine Research Center, Montreal, QC, Canada
- School of rehabilitation, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Zakaria Orfi
- CHU Sainte-Justine Research Center, Montreal, QC, Canada
- Department of pharmacology and physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Paul Fabre
- CHU Sainte-Justine Research Center, Montreal, QC, Canada
- Department of pharmacology and physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Thomas Molina
- CHU Sainte-Justine Research Center, Montreal, QC, Canada
- Department of pharmacology and physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Talita C Conte
- CHU Sainte-Justine Research Center, Montreal, QC, Canada
- Department of pharmacology and physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Karine Greffard
- Endocrinology and Nephrology Unit, CHU de Québec-Laval University Research Center, Quebec city, QC, Canada
| | | | - Jean-François Bilodeau
- Endocrinology and Nephrology Unit, CHU de Québec-Laval University Research Center, Quebec city, QC, Canada
- Department of Medicine, Faculty of Medicine, Laval University, Quebec city, QC, Canada
| | - Nicolas A Dumont
- CHU Sainte-Justine Research Center, Montreal, QC, Canada.
- School of rehabilitation, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.
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14
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Salvadori L, Chiappalupi S, Arato I, Mancuso F, Calvitti M, Marchetti MC, Riuzzi F, Calafiore R, Luca G, Sorci G. Sertoli Cells Improve Myogenic Differentiation, Reduce Fibrogenic Markers, and Induce Utrophin Expression in Human DMD Myoblasts. Biomolecules 2021; 11:1504. [PMID: 34680138 PMCID: PMC8533898 DOI: 10.3390/biom11101504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 10/05/2021] [Accepted: 10/08/2021] [Indexed: 12/12/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is an X-linked disease caused by mutations in DMD gene translating in lack of functional dystrophin and resulting in susceptibility of myofibers to rupture during contraction. Inflammation and fibrosis are critical hallmarks of DMD muscles, which undergo progressive degeneration leading to loss of independent ambulation in childhood and death by early adulthood. We reported that intraperitoneal injection of microencapsulated Sertoli cells (SeC) in dystrophic mice translates into recovery of muscle morphology and performance thanks to anti-inflammatory effects and induction of the dystrophin paralogue, utrophin at the muscle level, opening new avenues in the treatment of DMD. The aim of this study is to obtain information about the direct effects of SeC on myoblasts/myotubes, as a necessary step in view of a translational application of SeC-based approaches to DMD. We show that (i) SeC-derived factors stimulate cell proliferation in the early phase of differentiation in C2C12, and human healthy and DMD myoblasts; (ii) SeC delay the expression of differentiation markers in the early phase nevertheless stimulating terminal differentiation in DMD myoblasts; (iii) SeC restrain the fibrogenic potential of fibroblasts, and inhibit myoblast-myofibroblast transdifferentiation; and, (iv) SeC provide functional replacement of dystrophin in preformed DMD myotubes regardless of the mutation by inducing heregulin β1/ErbB2/ERK1/2-dependent utrophin expression. Altogether, these results show that SeC are endowed with promyogenic and antifibrotic effects on dystrophic myoblasts, further supporting their potential use in the treatment of DMD patients. Our data also suggest that SeC-based approaches might be useful in improving the early phase of muscle regeneration, during which myoblasts have to adequately proliferate to replace the damaged muscle mass.
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MESH Headings
- Animals
- Cell Differentiation/genetics
- Cell Proliferation/genetics
- Cell Transdifferentiation/genetics
- Disease Models, Animal
- Dystrophin/genetics
- Gene Expression Regulation/genetics
- Genetic Diseases, X-Linked/genetics
- Genetic Diseases, X-Linked/metabolism
- Genetic Diseases, X-Linked/pathology
- Humans
- Inflammation/genetics
- Inflammation/metabolism
- Inflammation/pathology
- Injections, Intraperitoneal
- MAP Kinase Signaling System/genetics
- Male
- Mice
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/pathology
- Myoblasts/metabolism
- Neuregulin-1/genetics
- Receptor, ErbB-2/genetics
- Regeneration/genetics
- Sertoli Cells/metabolism
- Sertoli Cells/pathology
- Utrophin/genetics
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Affiliation(s)
- Laura Salvadori
- Department of Translational Medicine, University of Piemonte Orientale, 28100 Novara, Italy;
- Interuniversity Institute of Myology (IIM), 06132 Perugia, Italy; (S.C.); (F.R.)
| | - Sara Chiappalupi
- Interuniversity Institute of Myology (IIM), 06132 Perugia, Italy; (S.C.); (F.R.)
- Department of Medicine and Surgery, University of Perugia, 06132 Perugia, Italy; (I.A.); (F.M.); (M.C.); (M.C.M.); (R.C.)
- Consorzio Interuniversitario Biotecnologie (CIB), 34127 Trieste, Italy
| | - Iva Arato
- Department of Medicine and Surgery, University of Perugia, 06132 Perugia, Italy; (I.A.); (F.M.); (M.C.); (M.C.M.); (R.C.)
| | - Francesca Mancuso
- Department of Medicine and Surgery, University of Perugia, 06132 Perugia, Italy; (I.A.); (F.M.); (M.C.); (M.C.M.); (R.C.)
| | - Mario Calvitti
- Department of Medicine and Surgery, University of Perugia, 06132 Perugia, Italy; (I.A.); (F.M.); (M.C.); (M.C.M.); (R.C.)
| | - Maria Cristina Marchetti
- Department of Medicine and Surgery, University of Perugia, 06132 Perugia, Italy; (I.A.); (F.M.); (M.C.); (M.C.M.); (R.C.)
| | - Francesca Riuzzi
- Interuniversity Institute of Myology (IIM), 06132 Perugia, Italy; (S.C.); (F.R.)
- Department of Medicine and Surgery, University of Perugia, 06132 Perugia, Italy; (I.A.); (F.M.); (M.C.); (M.C.M.); (R.C.)
- Consorzio Interuniversitario Biotecnologie (CIB), 34127 Trieste, Italy
| | - Riccardo Calafiore
- Department of Medicine and Surgery, University of Perugia, 06132 Perugia, Italy; (I.A.); (F.M.); (M.C.); (M.C.M.); (R.C.)
- Centro Biotecnologico Internazionale di Ricerca Traslazionale ad Indirizzo Endocrino, Metabolico ed Embrio-Riproduttivo (CIRTEMER), 06132 Perugia, Italy
| | - Giovanni Luca
- Department of Medicine and Surgery, University of Perugia, 06132 Perugia, Italy; (I.A.); (F.M.); (M.C.); (M.C.M.); (R.C.)
- Centro Biotecnologico Internazionale di Ricerca Traslazionale ad Indirizzo Endocrino, Metabolico ed Embrio-Riproduttivo (CIRTEMER), 06132 Perugia, Italy
- Centro Universitario di Ricerca sulla Genomica Funzionale (CURGeF), 06132 Perugia, Italy
| | - Guglielmo Sorci
- Interuniversity Institute of Myology (IIM), 06132 Perugia, Italy; (S.C.); (F.R.)
- Department of Medicine and Surgery, University of Perugia, 06132 Perugia, Italy; (I.A.); (F.M.); (M.C.); (M.C.M.); (R.C.)
- Consorzio Interuniversitario Biotecnologie (CIB), 34127 Trieste, Italy
- Centro Biotecnologico Internazionale di Ricerca Traslazionale ad Indirizzo Endocrino, Metabolico ed Embrio-Riproduttivo (CIRTEMER), 06132 Perugia, Italy
- Centro Universitario di Ricerca sulla Genomica Funzionale (CURGeF), 06132 Perugia, Italy
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15
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Howard ZM, Dorn LE, Lowe J, Gertzen MD, Ciccone P, Rastogi N, Odom GL, Accornero F, Chamberlain JS, Rafael-Fortney JA. Micro-dystrophin gene therapy prevents heart failure in an improved Duchenne muscular dystrophy cardiomyopathy mouse model. JCI Insight 2021; 6:146511. [PMID: 33651713 PMCID: PMC8119181 DOI: 10.1172/jci.insight.146511] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/24/2021] [Indexed: 12/19/2022] Open
Abstract
Gene replacement for Duchenne muscular dystrophy (DMD) with micro-dystrophins has entered clinical trials, but efficacy in preventing heart failure is unknown. Although most patients with DMD die from heart failure, cardiomyopathy is undetectable until the teens, so efficacy from trials in young boys will be unknown for a decade. Available DMD animal models were sufficient to demonstrate micro-dystrophin efficacy on earlier onset skeletal muscle pathology underlying loss of ambulation and respiratory insufficiency in patients. However, no mouse models progressed into heart failure, and dog models showed highly variable progression insufficient to evaluate efficacy of micro-dystrophin or other therapies on DMD heart failure. To overcome this barrier, we have generated the first DMD mouse model to our knowledge that reproducibly progresses into heart failure. This model shows cardiac inflammation and fibrosis occur prior to reduced function. Fibrosis does not continue to accumulate, but inflammation persists after function declines. We used this model to test micro-dystrophin gene therapy efficacy on heart failure prevention for the first time. Micro-dystrophin prevented declines in cardiac function and prohibited onset of inflammation and fibrosis. This model will allow identification of committed pathogenic steps to heart failure and testing of genetic and nongenetic therapies to optimize cardiac care for patients with DMD.
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Affiliation(s)
- Zachary M. Howard
- Department of Physiology & Cell Biology and Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Lisa E. Dorn
- Department of Physiology & Cell Biology and Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Jeovanna Lowe
- Department of Physiology & Cell Biology and Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Megan D. Gertzen
- Department of Physiology & Cell Biology and Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Pierce Ciccone
- Department of Physiology & Cell Biology and Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Neha Rastogi
- Department of Physiology & Cell Biology and Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Guy L. Odom
- Department of Neurology and Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Washington, Seattle, Washington, USA
| | - Federica Accornero
- Department of Physiology & Cell Biology and Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Jeffrey S. Chamberlain
- Department of Neurology and Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Washington, Seattle, Washington, USA
| | - Jill A. Rafael-Fortney
- Department of Physiology & Cell Biology and Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, Ohio, USA
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16
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Martin PT, Zygmunt DA, Ashbrook A, Hamilton S, Packer D, Birch SM, Bettis AK, Balog-Alvarez CJ, Guo LJ, Nghiem PP, Kornegay JN. Short-term treatment of golden retriever muscular dystrophy (GRMD) dogs with rAAVrh74.MHCK7.GALGT2 induces muscle glycosylation and utrophin expression but has no significant effect on muscle strength. PLoS One 2021; 16:e0248721. [PMID: 33770101 PMCID: PMC7997012 DOI: 10.1371/journal.pone.0248721] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 03/03/2021] [Indexed: 11/30/2022] Open
Abstract
We have examined the effects of intravenous (IV) delivery of rAAVrh74.MHCK7.GALGT2 in the golden retriever muscular dystrophy (GRMD) model of Duchenne Muscular Dystrophy (DMD). After baseline testing, GRMD dogs were treated at 3 months of age and reassessed at 6 months. This 3–6 month age range is a period of rapid disease progression, thus offering a relatively short window to establish treatment efficacy. Measures analyzed included muscle AAV transduction, GALGT2 transgene expression, GALGT2-induced glycosylation, muscle pathology, and muscle function. A total of five dogs were treated, 4 at 2x1014vg/kg and one at 6x1014vgkg. The 2x1014vg/kg dose led to transduction of regions of the heart with 1–3 vector genomes (vg) per nucleus, while most skeletal muscles were transduced with 0.25–0.5vg/nucleus. GALGT2-induced glycosylation paralleled levels of myofiber vg transduction, with about 90% of cardiomyocytes having increased glycosylation versus 20–35% of all myofibers across the skeletal muscles tested. Conclusions from phenotypic testing were limited by the small number of dogs. Treated dogs had less pronounced fibrosis and overall lesion severity when compared to control groups, but surprisingly no significant changes in limb muscle function measures. GALGT2-treated skeletal muscle and heart had elevated levels of utrophin protein expression and GALGT2-induced expression of glycosylated α dystroglycan, providing further evidence of a treatment effect. Serum chemistry, hematology, and cardiac function measures were largely unchanged by treatment. Cumulatively, these data show that short-term intravenous treatment of GRMD dogs with rAAVrh74.MHCK7.GALGT2 at high doses can induce muscle glycosylation and utrophin expression and may be safe over a short 3-month interval, but that such treatments had only modest effects on muscle pathology and did not significantly improve muscle strength.
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Affiliation(s)
- Paul T. Martin
- Center for Gene Therapy, Abigail Wexner Research Institute, Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, Ohio, United States of America
- * E-mail:
| | - Deborah A. Zygmunt
- Center for Gene Therapy, Abigail Wexner Research Institute, Nationwide Children’s Hospital, Columbus, Ohio, United States of America
| | - Anna Ashbrook
- Center for Gene Therapy, Abigail Wexner Research Institute, Nationwide Children’s Hospital, Columbus, Ohio, United States of America
| | - Sonia Hamilton
- Neuroscience Undergraduate Program, The Ohio State University, Columbus, Ohio, United States of America
| | - Davin Packer
- Neuroscience Graduate Program, The Ohio State University, Columbus, Ohio, United States of America
| | - Sharla M. Birch
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States of America
| | - Amanda K. Bettis
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States of America
| | - Cynthia J. Balog-Alvarez
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States of America
| | - Lee-Jae Guo
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States of America
| | - Peter P. Nghiem
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States of America
| | - Joe N. Kornegay
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States of America
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17
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Ellwood RA, Hewitt JE, Torregrossa R, Philp AM, Hardee JP, Hughes S, van de Klashorst D, Gharahdaghi N, Anupom T, Slade L, Deane CS, Cooke M, Etheridge T, Piasecki M, Antebi A, Lynch GS, Philp A, Vanapalli SA, Whiteman M, Szewczyk NJ. Mitochondrial hydrogen sulfide supplementation improves health in the C. elegans Duchenne muscular dystrophy model. Proc Natl Acad Sci U S A 2021; 118:e2018342118. [PMID: 33627403 PMCID: PMC7936346 DOI: 10.1073/pnas.2018342118] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder characterized by progressive muscle degeneration and weakness due to mutations in the dystrophin gene. The symptoms of DMD share similarities with those of accelerated aging. Recently, hydrogen sulfide (H2S) supplementation has been suggested to modulate the effects of age-related decline in muscle function, and metabolic H2S deficiencies have been implicated in affecting muscle mass in conditions such as phenylketonuria. We therefore evaluated the use of sodium GYY4137 (NaGYY), a H2S-releasing molecule, as a possible approach for DMD treatment. Using the dys-1(eg33) Caenorhabditis elegans DMD model, we found that NaGYY treatment (100 µM) improved movement, strength, gait, and muscle mitochondrial structure, similar to the gold-standard therapeutic treatment, prednisone (370 µM). The health improvements of either treatment required the action of the kinase JNK-1, the transcription factor SKN-1, and the NAD-dependent deacetylase SIR-2.1. The transcription factor DAF-16 was required for the health benefits of NaGYY treatment, but not prednisone treatment. AP39 (100 pM), a mitochondria-targeted H2S compound, also improved movement and strength in the dys-1(eg33) model, further implying that these improvements are mitochondria-based. Additionally, we found a decline in total sulfide and H2S-producing enzymes in dystrophin/utrophin knockout mice. Overall, our results suggest that H2S deficit may contribute to DMD pathology, and rectifying/overcoming the deficit with H2S delivery compounds has potential as a therapeutic approach to DMD treatment.
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MESH Headings
- Animals
- Caenorhabditis elegans/genetics
- Caenorhabditis elegans/metabolism
- Caenorhabditis elegans Proteins/genetics
- Caenorhabditis elegans Proteins/metabolism
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Dystrophin/deficiency
- Dystrophin/genetics
- Forkhead Transcription Factors/genetics
- Forkhead Transcription Factors/metabolism
- Gene Expression Regulation
- Humans
- Hydrogen Sulfide/metabolism
- Hydrogen Sulfide/pharmacology
- Locomotion/drug effects
- Locomotion/genetics
- Male
- Mice
- Mice, Inbred mdx
- Mitochondria, Muscle/drug effects
- Mitochondria, Muscle/metabolism
- Mitochondria, Muscle/pathology
- Mitogen-Activated Protein Kinases/genetics
- Mitogen-Activated Protein Kinases/metabolism
- Morpholines/metabolism
- Morpholines/pharmacology
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscular Dystrophy, Animal/drug therapy
- Muscular Dystrophy, Animal/genetics
- Muscular Dystrophy, Animal/metabolism
- Muscular Dystrophy, Animal/pathology
- Muscular Dystrophy, Duchenne/drug therapy
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/pathology
- Organophosphorus Compounds/metabolism
- Organophosphorus Compounds/pharmacology
- Organothiophosphorus Compounds/metabolism
- Organothiophosphorus Compounds/pharmacology
- Prednisone/pharmacology
- Sirtuins/genetics
- Sirtuins/metabolism
- Thiones/metabolism
- Thiones/pharmacology
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Utrophin/deficiency
- Utrophin/genetics
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Affiliation(s)
- Rebecca A Ellwood
- Medical Research Council (MRC) Versus Arthritis Centre for Musculoskeletal Ageing Research, Royal Derby Hospital, University of Nottingham, Derby DE22 3DT, United Kingdom
- Musculoskeletal Conditions, National Institute for Health Research Nottingham Biomedical Research Centre, Derby DE22 3DT, United Kingdom
| | - Jennifer E Hewitt
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409
- Molecular Genetics of Ageing, Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Roberta Torregrossa
- University of Exeter Medical School, University of Exeter, EX1 2LU Exeter, United Kingdom
| | - Ashleigh M Philp
- Mitochondrial Metabolism and Ageing, Garvan Institute of Medical Research, Sydney, NSW 2010, Australia
- St. Vincent's Clinical School, University of New South Wales (UNSW) Medicine, University of New South Wales Sydney, Sydney, NSW 2052, Australia
| | - Justin P Hardee
- Centre for Muscle Research, Department of Anatomy and Physiology, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Samantha Hughes
- HAN BioCentre, HAN University of Applied Sciences, Nijmegen 6525EM, The Netherlands
| | | | - Nima Gharahdaghi
- Medical Research Council (MRC) Versus Arthritis Centre for Musculoskeletal Ageing Research, Royal Derby Hospital, University of Nottingham, Derby DE22 3DT, United Kingdom
- Musculoskeletal Conditions, National Institute for Health Research Nottingham Biomedical Research Centre, Derby DE22 3DT, United Kingdom
| | - Taslim Anupom
- Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, TX 79409
| | - Luke Slade
- University of Exeter Medical School, University of Exeter, EX1 2LU Exeter, United Kingdom
- Sport and Health Sciences, University of Exeter, EX1 2LU Exeter, United Kingdom
| | - Colleen S Deane
- Sport and Health Sciences, University of Exeter, EX1 2LU Exeter, United Kingdom
- Living System Institute, University of Exeter, EX4 4QD Exeter, United Kingdom
| | - Michael Cooke
- Medical Research Council (MRC) Versus Arthritis Centre for Musculoskeletal Ageing Research, Royal Derby Hospital, University of Nottingham, Derby DE22 3DT, United Kingdom
- Musculoskeletal Conditions, National Institute for Health Research Nottingham Biomedical Research Centre, Derby DE22 3DT, United Kingdom
- Sport and Health Sciences, University of Exeter, EX1 2LU Exeter, United Kingdom
| | - Timothy Etheridge
- Sport and Health Sciences, University of Exeter, EX1 2LU Exeter, United Kingdom
| | - Mathew Piasecki
- Medical Research Council (MRC) Versus Arthritis Centre for Musculoskeletal Ageing Research, Royal Derby Hospital, University of Nottingham, Derby DE22 3DT, United Kingdom
- Musculoskeletal Conditions, National Institute for Health Research Nottingham Biomedical Research Centre, Derby DE22 3DT, United Kingdom
| | - Adam Antebi
- Molecular Genetics of Ageing, Max Planck Institute for Biology of Ageing, 50931 Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50931 Cologne, Germany
| | - Gordon S Lynch
- Centre for Muscle Research, Department of Anatomy and Physiology, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Andrew Philp
- Mitochondrial Metabolism and Ageing, Garvan Institute of Medical Research, Sydney, NSW 2010, Australia
- St. Vincent's Clinical School, University of New South Wales (UNSW) Medicine, University of New South Wales Sydney, Sydney, NSW 2052, Australia
| | - Siva A Vanapalli
- Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409
| | - Matthew Whiteman
- University of Exeter Medical School, University of Exeter, EX1 2LU Exeter, United Kingdom;
| | - Nathaniel J Szewczyk
- Medical Research Council (MRC) Versus Arthritis Centre for Musculoskeletal Ageing Research, Royal Derby Hospital, University of Nottingham, Derby DE22 3DT, United Kingdom;
- Musculoskeletal Conditions, National Institute for Health Research Nottingham Biomedical Research Centre, Derby DE22 3DT, United Kingdom
- Ohio Musculoskeletal and Neurologic Institute, Ohio University, Athens, OH 45701
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH 45701
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18
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Harris AR, Jreij P, Belardi B, Joffe AM, Bausch AR, Fletcher DA. Biased localization of actin binding proteins by actin filament conformation. Nat Commun 2020; 11:5973. [PMID: 33239610 PMCID: PMC7688639 DOI: 10.1038/s41467-020-19768-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 10/30/2020] [Indexed: 11/09/2022] Open
Abstract
The assembly of actin filaments into distinct cytoskeletal structures plays a critical role in cell physiology, but how proteins localize differentially to these structures within a shared cytoplasm remains unclear. Here, we show that the actin-binding domains of accessory proteins can be sensitive to filament conformational changes. Using a combination of live cell imaging and in vitro single molecule binding measurements, we show that tandem calponin homology domains (CH1-CH2) can be mutated to preferentially bind actin networks at the front or rear of motile cells. We demonstrate that the binding kinetics of CH1-CH2 domain mutants varies as actin filament conformation is altered by perturbations that include stabilizing drugs and other binding proteins. These findings suggest that conformational changes of actin filaments in cells could help to direct accessory binding proteins to different actin cytoskeletal structures through a biophysical feedback loop.
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Affiliation(s)
- Andrew R Harris
- Department of Bioengineering and Biophysics Program, University of California, Berkeley, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA
| | - Pamela Jreij
- Department of Bioengineering and Biophysics Program, University of California, Berkeley, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA
| | - Brian Belardi
- Department of Bioengineering and Biophysics Program, University of California, Berkeley, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA
| | - Aaron M Joffe
- Department of Bioengineering and Biophysics Program, University of California, Berkeley, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA
| | - Andreas R Bausch
- Lehrstuhl für Biophysik (E27), Technische Universität München, Garching, 85748, Germany
| | - Daniel A Fletcher
- Department of Bioengineering and Biophysics Program, University of California, Berkeley, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA.
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, 648 Stanley Hall MC 1762, Berkeley, CA, 94720, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, 94158, USA.
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19
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Banks GB, Chamberlain JS, Odom GL. Microutrophin expression in dystrophic mice displays myofiber type differences in therapeutic effects. PLoS Genet 2020; 16:e1009179. [PMID: 33175853 PMCID: PMC7682874 DOI: 10.1371/journal.pgen.1009179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 11/23/2020] [Accepted: 10/06/2020] [Indexed: 12/28/2022] Open
Abstract
Gene therapy approaches for DMD using recombinant adeno-associated viral (rAAV) vectors to deliver miniaturized (or micro) dystrophin genes to striated muscles have shown significant progress. However, concerns remain about the potential for immune responses against dystrophin in some patients. Utrophin, a developmental paralogue of dystrophin, may provide a viable treatment option. Here we examine the functional capacity of an rAAV-mediated microutrophin (μUtrn) therapy in the mdx4cv mouse model of DMD. We found that rAAV-μUtrn led to improvement in dystrophic histopathology & mostly restored the architecture of the neuromuscular and myotendinous junctions. Physiological studies of tibialis anterior muscles indicated peak force maintenance, with partial improvement of specific force. A fundamental question for μUtrn therapeutics is not only can it replace critical functions of dystrophin, but whether full-length utrophin impacts the therapeutic efficacy of the smaller, highly expressed μUtrn. As such, we found that μUtrn significantly reduced the spacing of the costameric lattice relative to full-length utrophin. Further, immunostaining suggested the improvement in dystrophic pathophysiology was largely influenced by favored correction of fast 2b fibers. However, unlike μUtrn, μdystrophin (μDys) expression did not show this fiber type preference. Interestingly, μUtrn was better able to protect 2a and 2d fibers in mdx:utrn-/- mice than in mdx4cv mice where the endogenous full-length utrophin was most prevalent. Altogether, these data are consistent with the role of steric hindrance between full-length utrophin & μUtrn within the sarcolemma. Understanding the stoichiometry of this effect may be important for predicting clinical efficacy.
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MESH Headings
- Animals
- Dependovirus/genetics
- Disease Models, Animal
- Dystrophin/genetics
- Gene Transfer Techniques
- Genetic Therapy/methods
- Genetic Vectors/genetics
- HEK293 Cells
- Humans
- Mice
- Mice, Inbred mdx
- Microscopy, Electron
- Muscle Contraction
- Muscle Fibers, Skeletal/cytology
- Muscle Fibers, Skeletal/pathology
- Muscle Fibers, Skeletal/ultrastructure
- Muscle, Skeletal
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/pathology
- Muscular Dystrophy, Duchenne/therapy
- Neuromuscular Junction/pathology
- Neuromuscular Junction/ultrastructure
- Sarcolemma/pathology
- Sarcolemma/ultrastructure
- Utrophin/genetics
- Utrophin/therapeutic use
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Affiliation(s)
- Glen B. Banks
- Department of Neurology, University of Washington, Seattle, Washington, United States of America
- Department of Medicine, University of Washington, Seattle, Washington, United States of America
- Wellstone Muscular Dystrophy Specialized Research Center, University of Washington, Seattle, Washington, United States of America
| | - Jeffrey S. Chamberlain
- Department of Neurology, University of Washington, Seattle, Washington, United States of America
- Department of Medicine, University of Washington, Seattle, Washington, United States of America
- Wellstone Muscular Dystrophy Specialized Research Center, University of Washington, Seattle, Washington, United States of America
- Department of BioChemistry, University of Washington, Seattle, Washington, United States of America
| | - Guy L. Odom
- Department of Neurology, University of Washington, Seattle, Washington, United States of America
- Department of Medicine, University of Washington, Seattle, Washington, United States of America
- Wellstone Muscular Dystrophy Specialized Research Center, University of Washington, Seattle, Washington, United States of America
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20
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Wilkinson IVL, Perkins KJ, Dugdale H, Moir L, Vuorinen A, Chatzopoulou M, Squire SE, Monecke S, Lomow A, Geese M, Charles PD, Burch P, Tinsley JM, Wynne GM, Davies SG, Wilson FX, Rastinejad F, Mohammed S, Davies KE, Russell AJ. Chemical Proteomics and Phenotypic Profiling Identifies the Aryl Hydrocarbon Receptor as a Molecular Target of the Utrophin Modulator Ezutromid. Angew Chem Int Ed Engl 2020; 59:2420-2428. [PMID: 31755636 PMCID: PMC7003794 DOI: 10.1002/anie.201912392] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/13/2019] [Indexed: 12/20/2022]
Abstract
Duchenne muscular dystrophy (DMD) is a fatal muscle-wasting disease arising from mutations in the dystrophin gene. Upregulation of utrophin to compensate for the missing dystrophin offers a potential therapy independent of patient genotype. The first-in-class utrophin modulator ezutromid/SMT C1100 was developed from a phenotypic screen through to a Phase 2 clinical trial. Promising efficacy and evidence of target engagement was observed in DMD patients after 24 weeks of treatment, however trial endpoints were not met after 48 weeks. The objective of this study was to understand the mechanism of action of ezutromid which could explain the lack of sustained efficacy and help development of new generations of utrophin modulators. Using chemical proteomics and phenotypic profiling we show that the aryl hydrocarbon receptor (AhR) is a target of ezutromid. Several lines of evidence demonstrate that ezutromid binds AhR with an apparent KD of 50 nm and behaves as an AhR antagonist. Furthermore, other reported AhR antagonists also upregulate utrophin, showing that this pathway, which is currently being explored in other clinical applications including oncology and rheumatoid arthritis, could also be exploited in future DMD therapies.
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Affiliation(s)
- Isabel V. L. Wilkinson
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOxfordOX1 3TAUK
| | - Kelly J. Perkins
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordSir Henry Wellcome Building of Gene FunctionSouth Parks RoadOxfordOX1 3PTUK
| | - Hannah Dugdale
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordSir Henry Wellcome Building of Gene FunctionSouth Parks RoadOxfordOX1 3PTUK
| | - Lee Moir
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordSir Henry Wellcome Building of Gene FunctionSouth Parks RoadOxfordOX1 3PTUK
| | - Aini Vuorinen
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOxfordOX1 3TAUK
| | - Maria Chatzopoulou
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOxfordOX1 3TAUK
| | - Sarah E. Squire
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordSir Henry Wellcome Building of Gene FunctionSouth Parks RoadOxfordOX1 3PTUK
| | - Sebastian Monecke
- Evotec International GmbHManfred Eigen CampusEssener Bogen 722419HamburgGermany
| | - Alexander Lomow
- Evotec International GmbHManfred Eigen CampusEssener Bogen 722419HamburgGermany
| | - Marcus Geese
- Evotec International GmbHManfred Eigen CampusEssener Bogen 722419HamburgGermany
| | - Philip D. Charles
- Department of BiochemistryUniversity of OxfordSouth Parks RdOxfordOX1 3QUUK
- Target Discovery InstituteUniversity of OxfordOld Road CampusRoosevelt DriveOxfordOX3 7FZUK
| | - Peter Burch
- Summit Therapeutics plc.136a Eastern Avenue, Milton ParkAbingdonOxfordshireOX14 4SBUK
| | - Jonathan M. Tinsley
- Summit Therapeutics plc.136a Eastern Avenue, Milton ParkAbingdonOxfordshireOX14 4SBUK
| | - Graham M. Wynne
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOxfordOX1 3TAUK
| | - Stephen G. Davies
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOxfordOX1 3TAUK
| | - Francis X. Wilson
- Summit Therapeutics plc.136a Eastern Avenue, Milton ParkAbingdonOxfordshireOX14 4SBUK
| | - Fraydoon Rastinejad
- Target Discovery InstituteUniversity of OxfordOld Road CampusRoosevelt DriveOxfordOX3 7FZUK
| | - Shabaz Mohammed
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOxfordOX1 3TAUK
- Department of BiochemistryUniversity of OxfordSouth Parks RdOxfordOX1 3QUUK
| | - Kay E. Davies
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordSir Henry Wellcome Building of Gene FunctionSouth Parks RoadOxfordOX1 3PTUK
| | - Angela J. Russell
- Department of ChemistryUniversity of OxfordChemistry Research LaboratoryMansfield RoadOxfordOX1 3TAUK
- Department of PharmacologyUniversity of OxfordMansfield RoadOxfordOX1 3PQUK
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21
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Guiraud S, Edwards B, Babbs A, Squire SE, Berg A, Moir L, Wood MJ, Davies KE. The potential of utrophin and dystrophin combination therapies for Duchenne muscular dystrophy. Hum Mol Genet 2019; 28:2189-2200. [PMID: 30990876 PMCID: PMC6586144 DOI: 10.1093/hmg/ddz049] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 02/18/2019] [Accepted: 02/26/2019] [Indexed: 01/01/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a lethal neuromuscular disorder caused by loss of dystrophin. Several therapeutic modalities are currently in clinical trials but none will achieve maximum functional rescue and full disease correction. Therefore, we explored the potential of combining the benefits of dystrophin with increases of utrophin, an autosomal paralogue of dystrophin. Utrophin and dystrophin can be co-expressed and co-localized at the same muscle membrane. Wild-type (wt) levels of dystrophin are not significantly affected by a moderate increase of utrophin whereas higher levels of utrophin reduce wt dystrophin, suggesting a finite number of actin binding sites at the sarcolemma. Thus, utrophin upregulation strategies may be applied to the more mildly affected Becker patients with lower dystrophin levels. Whereas increased dystrophin in wt animals does not offer functional improvement, overexpression of utrophin in wt mice results in a significant supra-functional benefit over wt. These findings highlight an additive benefit of the combined therapy and potential new unique roles of utrophin. Finally, we show a 30% restoration of wt dystrophin levels, using exon-skipping, together with increased utrophin levels restores dystrophic muscle function to wt levels offering greater therapeutic benefit than either single approach alone. Thus, this combination therapy results in additive functional benefit and paves the way for potential future combinations of dystrophin- and utrophin-based strategies.
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Affiliation(s)
- Simon Guiraud
- MDUK Oxford Neuromuscular Centre, Department of Physiology, Anatomy and Genetics, Oxford, UK
| | - Benjamin Edwards
- MDUK Oxford Neuromuscular Centre, Department of Physiology, Anatomy and Genetics, Oxford, UK
| | - Arran Babbs
- MDUK Oxford Neuromuscular Centre, Department of Physiology, Anatomy and Genetics, Oxford, UK
| | - Sarah E Squire
- MDUK Oxford Neuromuscular Centre, Department of Physiology, Anatomy and Genetics, Oxford, UK
| | - Adam Berg
- MDUK Oxford Neuromuscular Centre, Department of Physiology, Anatomy and Genetics, Oxford, UK
| | - Lee Moir
- MDUK Oxford Neuromuscular Centre, Department of Physiology, Anatomy and Genetics, Oxford, UK
| | - Matthew J Wood
- MDUK Oxford Neuromuscular Centre, Department of Physiology, Anatomy and Genetics, Oxford, UK
| | - Kay E Davies
- MDUK Oxford Neuromuscular Centre, Department of Physiology, Anatomy and Genetics, Oxford, UK
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22
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Lindsay A, McCourt PM, Karachunski P, Lowe DA, Ervasti JM. Xanthine oxidase is hyper-active in Duchenne muscular dystrophy. Free Radic Biol Med 2018; 129:364-371. [PMID: 30312761 PMCID: PMC6599518 DOI: 10.1016/j.freeradbiomed.2018.10.404] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/21/2018] [Accepted: 10/04/2018] [Indexed: 11/30/2022]
Abstract
Generation of superoxide by xanthine oxidase can be stimulated under ischemic and aberrant calcium homeostasis. Because patients and mice with Duchenne muscular dystrophy (DMD) suffer from ischemia and excessive calcium influx, we tested the hypothesis that xanthine oxidase activity is elevated and contributes to disease pathology. Xanthine oxidase activity was measured by urinary isoxanthopterin in DMD patients at rest and in response to exercise. Urinary isoxanthopterin/creatinine was elevated compared to age-matched controls and Becker muscular dystrophy (BMD) patients. Concentrations were also increased after a six minute walk test in ambulatory patients. We also measured urinary isoxanthopterin in wildtype mice and a number of dystrophic mouse models; the DMD mouse model (mdx), mdx mice overexpressing a variety of transgenic miniaturized and chimeric skeletal muscle-specific dystrophins and utrophin and the β-sarcoglycan deficient (Scgb-/-) mouse which represents type 2E human limb-girdle muscular dystrophy. Mdx and Scgb-/-mice had greater urinary isoxanthopterin/creatinine than wildtype mice while mdx mice expressing dystrophin or utrophin linking the extracellular matrix to the actin cytoskeleton were not different than wildtype. We also measured higher levels of urinary ortho-tyrosine in humans and mice deficient for dystrophin to confirm elevated oxidative stress. Surprisingly, mdx had lower xanthine oxidase protein levels and higher mRNA in gastrocnemius muscle compared to wildtype mice, however, the enzymatic activity of skeletal muscle xanthine oxidase was elevated above wildtype and a transgenic rescued mdx mouse (DysΔMTB-mdx). Downhill treadmill running also caused significant increases in mdx urinary isoxanthopterin that was prevented with the xanthine oxidase inhibitor allopurinol. Similarly, in vitro eccentric contraction-induced force drop of mdx muscle was attenuated by the allopurinol metabolite, oxypurinol. Together, our data suggests hyper-activity of xanthine oxidase in DMD, identifies xanthine oxidase activity as a contributing factor in eccentric contraction-induced force drop of dystrophin-deficient skeletal muscle and highlights the potential of isoxanthopterin as a noninvasive biomarker in DMD.
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MESH Headings
- Adolescent
- Allopurinol/pharmacology
- Animals
- Biomarkers/urine
- Case-Control Studies
- Creatinine/urine
- Dystrophin/deficiency
- Dystrophin/genetics
- Enzyme Inhibitors/pharmacology
- Gene Expression Regulation
- Humans
- Male
- Mice
- Mice, Inbred mdx
- Muscle Contraction/drug effects
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/enzymology
- Muscle, Skeletal/physiopathology
- Muscular Dystrophy, Animal/drug therapy
- Muscular Dystrophy, Animal/enzymology
- Muscular Dystrophy, Animal/genetics
- Muscular Dystrophy, Animal/physiopathology
- Muscular Dystrophy, Duchenne/drug therapy
- Muscular Dystrophy, Duchenne/enzymology
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/physiopathology
- Oxypurinol/pharmacology
- Sarcoglycans/deficiency
- Sarcoglycans/genetics
- Tyrosine/urine
- Utrophin/deficiency
- Utrophin/genetics
- Xanthine Oxidase/genetics
- Xanthine Oxidase/urine
- Xanthopterin/urine
- Young Adult
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Affiliation(s)
- Angus Lindsay
- Division of Rehabilitation Science and Division of Physical Therapy, Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, USA; Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, USA.
| | - Preston M McCourt
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, USA
| | - Peter Karachunski
- Department of Pediatrics, University of Minnesota, Minneapolis, USA; Department of Neurology, University of Minnesota, Minneapolis, USA
| | - Dawn A Lowe
- Division of Rehabilitation Science and Division of Physical Therapy, Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, USA
| | - James M Ervasti
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, USA
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23
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Culley S, Tosheva KL, Matos Pereira P, Henriques R. SRRF: Universal live-cell super-resolution microscopy. Int J Biochem Cell Biol 2018; 101:74-79. [PMID: 29852248 PMCID: PMC6025290 DOI: 10.1016/j.biocel.2018.05.014] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 05/21/2018] [Accepted: 05/23/2018] [Indexed: 11/30/2022]
Abstract
Super-resolution microscopy techniques break the diffraction limit of conventional optical microscopy to achieve resolutions approaching tens of nanometres. The major advantage of such techniques is that they provide resolutions close to those obtainable with electron microscopy while maintaining the benefits of light microscopy such as a wide palette of high specificity molecular labels, straightforward sample preparation and live-cell compatibility. Despite this, the application of super-resolution microscopy to dynamic, living samples has thus far been limited and often requires specialised, complex hardware. Here we demonstrate how a novel analytical approach, Super-Resolution Radial Fluctuations (SRRF), is able to make live-cell super-resolution microscopy accessible to a wider range of researchers. We show its applicability to live samples expressing GFP using commercial confocal as well as laser- and LED-based widefield microscopes, with the latter achieving long-term timelapse imaging with minimal photobleaching.
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Affiliation(s)
- Siân Culley
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; Department of Cell and Developmental Biology, University College London, Gower Street, London, WC1E 6BT, UK; The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Kalina L Tosheva
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; Department of Cell and Developmental Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Pedro Matos Pereira
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; Department of Cell and Developmental Biology, University College London, Gower Street, London, WC1E 6BT, UK; The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Ricardo Henriques
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; Department of Cell and Developmental Biology, University College London, Gower Street, London, WC1E 6BT, UK; The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
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Cho EB, Yoo W, Yoon SK, Yoon JB. β-dystroglycan is regulated by a balance between WWP1-mediated degradation and protection from WWP1 by dystrophin and utrophin. Biochim Biophys Acta Mol Basis Dis 2018; 1864:2199-2213. [PMID: 29635000 DOI: 10.1016/j.bbadis.2018.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 03/20/2018] [Accepted: 04/03/2018] [Indexed: 01/07/2023]
Abstract
Dystroglycan is a ubiquitous membrane protein that functions as a mechanical connection between the extracellular matrix and cytoskeleton. In skeletal muscle, dystroglycan plays an indispensable role in regulating muscle regeneration; a malfunction in dystroglycan is associated with muscular dystrophy. The regulation of dystroglycan stability is poorly understood. Here, we report that WWP1, a member of NEDD4 E3 ubiquitin ligase family, promotes ubiquitination and subsequent degradation of β-dystroglycan. Our results indicate that dystrophin and utrophin protect β-dystroglycan from WWP1-mediated degradation by competing with WWP1 for the shared binding site at the cytosolic tail of β-dystroglycan. In addition, we show that a missense mutation (arginine 440 to glutamine) in WWP1-which is known to cause muscular dystrophy in chickens-increases the ubiquitin ligase-mediated ubiquitination of both β-dystroglycan and WWP1. The R440Q missense mutation in WWP1 decreases HECT domain-mediated intramolecular interactions to relieve autoinhibition of the enzyme. Our results provide new insight into the regulation of β-dystroglycan degradation by WWP1 and other Nedd4 family members and improves our understanding of dystroglycan-related disorders.
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Affiliation(s)
- Eun-Bee Cho
- Department of Biochemistry, College of Life Science & Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea
| | - Wonjin Yoo
- Department of Biochemistry, College of Life Science & Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea
| | - Sungjoo Kim Yoon
- Department of Medical Lifesciences, The Catholic University of Korea, Seoul 137-701, Republic of Korea
| | - Jong-Bok Yoon
- Department of Biochemistry, College of Life Science & Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea.
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Abstract
Measuring functional outcomes in the treatment of muscular dystrophy is an essential aspect of preclinical testing. The assessment of voluntary ambulation in mouse models is a non-invasive and reproducible activity assay that is directly analogous to measures of patient ambulation such as the 6-minute walk test and related mobility scores. Many common methods for testing mouse ambulation speed and distance are based on the open field test, where an animal's free movement within an arena is measured over time. One major downside to this approach is that commercial software and equipment for high-resolution motion tracking is expensive and may require transferring mice to specialized facilities for testing. Here, we describe a low-cost, video-based system for measuring mouse ambulation that utilizes free and open-source software. Using this protocol, we demonstrate that voluntary ambulation in the dystrophin-null mdx mouse model for Duchenne muscular dystrophy (DMD) is decreased relative to wild-type mouse activity. In mdx mice expressing the utrophin transgene, these activity deficits are not observed and the total distance traveled is indistinguishable from wild-type mice. This method is effective for measuring changes in voluntary ambulation associated with dystrophic pathology, and provides a versatile platform that can be readily adapted to diverse research settings.
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Affiliation(s)
- Elizabeth M Gibbs
- Department of Integrative Biology and Physiology, University of California; Center for Duchenne Muscular Dystrophy, University of California
| | - Rachelle H Crosbie-Watson
- Department of Integrative Biology and Physiology, University of California; Center for Duchenne Muscular Dystrophy, University of California; Department of Neurology, David Geffen School of Medicine, University of California; Molecular Biology Institute, University of California;
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26
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El Refaey M, Xu L, Gao Y, Canan BD, Adesanya TMA, Warner SC, Akagi K, Symer DE, Mohler PJ, Ma J, Janssen PML, Han R. In Vivo Genome Editing Restores Dystrophin Expression and Cardiac Function in Dystrophic Mice. Circ Res 2017; 121:923-929. [PMID: 28790199 PMCID: PMC5623072 DOI: 10.1161/circresaha.117.310996] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 08/03/2017] [Accepted: 08/07/2017] [Indexed: 01/16/2023]
Abstract
RATIONALE Duchenne muscular dystrophy is a severe inherited form of muscular dystrophy caused by mutations in the reading frame of the dystrophin gene disrupting its protein expression. Dystrophic cardiomyopathy is a leading cause of death in Duchenne muscular dystrophy patients, and currently no effective treatment exists to halt its progression. Recent advancement in genome editing technologies offers a promising therapeutic approach in restoring dystrophin protein expression. However, the impact of this approach on Duchenne muscular dystrophy cardiac function has yet to be evaluated. Therefore, we assessed the therapeutic efficacy of CRISPR (clustered regularly interspaced short palindromic repeats)-mediated genome editing on dystrophin expression and cardiac function in mdx/Utr +/- mice after a single systemic delivery of recombinant adeno-associated virus. OBJECTIVE To examine the efficiency and physiological impact of CRISPR-mediated genome editing on cardiac dystrophin expression and function in dystrophic mice. METHODS AND RESULTS Here, we packaged SaCas9 (clustered regularly interspaced short palindromic repeat-associated 9 from Staphylococcus aureus) and guide RNA constructs into an adeno-associated virus vector and systemically delivered them to mdx/Utr +/- neonates. We showed that CRIPSR-mediated genome editing efficiently excised the mutant exon 23 in dystrophic mice, and immunofluorescence data supported the restoration of dystrophin protein expression in dystrophic cardiac muscles to a level approaching 40%. Moreover, there was a noted restoration in the architecture of cardiac muscle fibers and a reduction in the extent of fibrosis in dystrophin-deficient hearts. The contractility of cardiac papillary muscles was also restored in CRISPR-edited cardiac muscles compared with untreated controls. Furthermore, our targeted deep sequencing results confirmed that our adeno-associated virus-CRISPR/Cas9 strategy was very efficient in deleting the ≈23 kb of intervening genomic sequences. CONCLUSIONS This study provides evidence for using CRISPR-based genome editing as a potential therapeutic approach for restoring dystrophic cardiomyopathy structurally and functionally.
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MESH Headings
- Animals
- CRISPR-Associated Proteins/genetics
- CRISPR-Associated Proteins/metabolism
- CRISPR-Cas Systems
- Cardiomyopathies/genetics
- Cardiomyopathies/metabolism
- Cardiomyopathies/physiopathology
- Cardiomyopathies/therapy
- Clustered Regularly Interspaced Short Palindromic Repeats
- Dependovirus/genetics
- Disease Models, Animal
- Dystrophin/genetics
- Dystrophin/metabolism
- Exons
- Fibrosis
- Gene Editing/methods
- Gene Expression Regulation
- Genetic Predisposition to Disease
- Genetic Therapy/methods
- Genetic Vectors
- High-Throughput Nucleotide Sequencing
- Mice, Inbred mdx
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/physiopathology
- Muscular Dystrophy, Duchenne/therapy
- Mutation
- Myocardial Contraction
- Papillary Muscles/metabolism
- Papillary Muscles/pathology
- Papillary Muscles/physiopathology
- Phenotype
- RNA, Guide, CRISPR-Cas Systems/genetics
- RNA, Guide, CRISPR-Cas Systems/metabolism
- Recovery of Function
- Utrophin/genetics
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Affiliation(s)
- Mona El Refaey
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - Li Xu
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - Yandi Gao
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - Benjamin D Canan
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - T M Ayodele Adesanya
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - Sarah C Warner
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - Keiko Akagi
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - David E Symer
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - Peter J Mohler
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - Jianjie Ma
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - Paul M L Janssen
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus
| | - Renzhi Han
- From the Department of Surgery, Davis Heart and Lung Research Institute, Biomedical Sciences Graduate Program, Biophysics Graduate Program (M.E.R., L.X., Y.G., T.M.A.A., J.M., R.H.) and Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute (B.D.C., P.J.M., P.M.L.J.), The Ohio State University Wexner Medical Center, Columbus; Genomics Shared Resource, The Ohio State University Comprehensive Cancer Center, Columbus (S.C.W., D.E.S.); and Department of Cancer Biology and Genetics (K.A., D.E.S.) and Human Cancer Genetics Program, and Department of Biomedical Informatics (adjunct) (D.E.S.), The Ohio State University, Columbus.
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27
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Kennedy TL, Swiderski K, Murphy KT, Gehrig SM, Curl CL, Chandramouli C, Febbraio MA, Delbridge LMD, Koopman R, Lynch GS. BGP-15 Improves Aspects of the Dystrophic Pathology in mdx and dko Mice with Differing Efficacies in Heart and Skeletal Muscle. Am J Pathol 2016; 186:3246-3260. [PMID: 27750047 DOI: 10.1016/j.ajpath.2016.08.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 08/14/2016] [Accepted: 08/17/2016] [Indexed: 11/19/2022]
Abstract
Duchenne muscular dystrophy is a severe and progressive striated muscle wasting disorder that leads to premature death from respiratory and/or cardiac failure. We have previously shown that treatment of young dystrophic mdx and dystrophin/utrophin null (dko) mice with BGP-15, a coinducer of heat shock protein 72, ameliorated the dystrophic pathology. We therefore tested the hypothesis that later-stage BGP-15 treatment would similarly benefit older mdx and dko mice when the dystrophic pathology was already well established. Later stage treatment of mdx or dko mice with BGP-15 did not improve maximal force of tibialis anterior (TA) muscles (in situ) or diaphragm muscle strips (in vitro). However, collagen deposition (fibrosis) was reduced in TA muscles of BGP-15-treated dko mice but unchanged in TA muscles of treated mdx mice and diaphragm of treated mdx and dko mice. We also examined whether BGP-15 treatment could ameliorate aspects of the cardiac pathology, and in young dko mice it reduced collagen deposition and improved both membrane integrity and systolic function. These results confirm BGP-15's ability to improve aspects of the dystrophic pathology but with differing efficacies in heart and skeletal muscles at different stages of the disease progression. These findings support a role for BGP-15 among a suite of pharmacological therapies for Duchenne muscular dystrophy and related disorders.
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Affiliation(s)
- Tahnee L Kennedy
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Melbourne, Victoria
| | - Kristy Swiderski
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Melbourne, Victoria
| | - Kate T Murphy
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Melbourne, Victoria
| | - Stefan M Gehrig
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Melbourne, Victoria
| | - Claire L Curl
- Cardiac Phenomics Laboratory, Department of Physiology, The University of Melbourne, Melbourne, Victoria
| | - Chanchal Chandramouli
- Cardiac Phenomics Laboratory, Department of Physiology, The University of Melbourne, Melbourne, Victoria
| | - Mark A Febbraio
- Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Lea M D Delbridge
- Cardiac Phenomics Laboratory, Department of Physiology, The University of Melbourne, Melbourne, Victoria
| | - René Koopman
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Melbourne, Victoria
| | - Gordon S Lynch
- Basic and Clinical Myology Laboratory, Department of Physiology, The University of Melbourne, Melbourne, Victoria.
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28
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Singh SM, Bandi S, Mallela KMG. The N- and C-Terminal Domains Differentially Contribute to the Structure and Function of Dystrophin and Utrophin Tandem Calponin-Homology Domains. Biochemistry 2015; 54:6942-50. [PMID: 26516677 DOI: 10.1021/acs.biochem.5b00969] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Dystrophin and utrophin are two muscle proteins involved in Duchenne/Becker muscular dystrophy. Both proteins use tandem calponin-homology (CH) domains to bind to F-actin. We probed the role of N-terminal CH1 and C-terminal CH2 domains in the structure and function of dystrophin tandem CH domain and compared with our earlier results on utrophin to understand the unifying principles of how tandem CH domains work. Actin cosedimentation assays indicate that the isolated CH2 domain of dystrophin weakly binds to F-actin compared to the full-length tandem CH domain. In contrast, the isolated CH1 domain binds to F-actin with an affinity similar to that of the full-length tandem CH domain. Thus, the obvious question is why the dystrophin tandem CH domain requires CH2, when its actin binding is determined primarily by CH1. To answer, we probed the structural stabilities of CH domains. The isolated CH1 domain is very unstable and is prone to serious aggregation. The isolated CH2 domain is very stable, similar to the full-length tandem CH domain. These results indicate that the main role of CH2 is to stabilize the tandem CH domain structure. These conclusions from dystrophin agree with our earlier results on utrophin, indicating that this phenomenon of differential contribution of CH domains to the structure and function of tandem CH domains may be quite general. The N-terminal CH1 domains primarily determine the actin binding function whereas the C-terminal CH2 domains primarily determine the structural stability of tandem CH domains, and the extent of stabilization depends on the strength of inter-CH domain interactions.
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Affiliation(s)
- Surinder M Singh
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, and ‡Program in Structural Biology and Biochemistry, University of Colorado Anschutz Medical Campus , Aurora, Colorado 80045, United States
| | - Swati Bandi
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, and ‡Program in Structural Biology and Biochemistry, University of Colorado Anschutz Medical Campus , Aurora, Colorado 80045, United States
| | - Krishna M G Mallela
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, and ‡Program in Structural Biology and Biochemistry, University of Colorado Anschutz Medical Campus , Aurora, Colorado 80045, United States
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29
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McDonald AA, Hebert SL, McLoon LK. Sparing of the extraocular muscles in mdx mice with absent or reduced utrophin expression: A life span analysis. Neuromuscul Disord 2015; 25:873-87. [PMID: 26429098 PMCID: PMC4630113 DOI: 10.1016/j.nmd.2015.09.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 08/08/2015] [Accepted: 09/01/2015] [Indexed: 11/26/2022]
Abstract
Sparing of the extraocular muscles in muscular dystrophy is controversial. To address the potential role of utrophin in this sparing, mdx:utrophin(+/-) and mdx:utrophin(-/-) mice were examined for changes in myofiber size, central nucleation, and Pax7-positive and MyoD-positive cell density at intervals over their life span. Known to be spared in the mdx mouse, and contrary to previous reports, the extraocular muscles from both the mdx:utrophin(+/-) and mdx:utrophin(-/-) mice were also morphologically spared. In the mdx:utrophin(+/)(-) mice, which have a normal life span compared to the mdx:utrophin(-/-) mice, the myofibers were larger at 3 and 12 months than the wild type age-matched eye muscles. While there was a significant increase in central nucleation in the extraocular muscles from all mdx:utrophin(+/)(-) mice, the levels were still very low compared to age-matched limb skeletal muscles. Pax7- and MyoD-positive myogenic precursor cell populations were retained and were similar to age-matched wild type controls. These results support the hypothesis that utrophin is not involved in extraocular muscle sparing in these genotypes. In addition, it appears that these muscles retain the myogenic precursors that would allow them to maintain their regenerative capacity and normal morphology over a lifetime even in these more severe models of muscular dystrophy.
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Affiliation(s)
- Abby A McDonald
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN, USA; Graduate Program in Molecular, Cellular, Developmental Biology and Genetics, University of Minnesota, Minneapolis, MN, USA
| | - Sadie L Hebert
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN, USA
| | - Linda K McLoon
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN, USA; Graduate Program in Molecular, Cellular, Developmental Biology and Genetics, University of Minnesota, Minneapolis, MN, USA; Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA.
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30
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Ghosh T, Basu U. Cis-Acting Sequence Elements and Upstream Open Reading Frame in Mouse Utrophin-A 5'-UTR Repress Cap-Dependent Translation. PLoS One 2015; 10:e0134809. [PMID: 26230628 PMCID: PMC4521823 DOI: 10.1371/journal.pone.0134809] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 07/14/2015] [Indexed: 11/18/2022] Open
Abstract
Utrophin, the autosomal homologue of dystrophin can functionally compensate for dystrophin deficiency. Utrophin upregulation could therefore be a therapeutic strategy in Duchenne Muscular Dystrophy (DMD) that arises from mutation in dystrophin gene. In contrast to its transcriptional regulation, mechanisms operating at post-transcriptional level of utrophin expression have not been well documented. Although utrophin-A 5'-UTR has been reported with internal ribosome entry site (IRES), its inhibitory effect on translation is also evident. In the present study we therefore aimed to compare relative contribution of cap-independent and cap-dependent translation with mouse utrophin-A 5'-UTR through m7G-capped and A-capped mRNA transfection based reporter assay. Our results demonstrate that cap-independent translation with utrophin-A 5'-UTR is not as strong as viral IRES. However, cap-independent mode has significant contribution as cap-dependent translation is severely repressed with utrophin-A 5'-UTR. We further identified two sequence elements and one upstream open reading frame in utrophin-A 5'-UTR responsible for repression. The repressor elements in utrophin-A 5'-UTR may be targeted for utrophin upregulation.
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Affiliation(s)
- Trinath Ghosh
- Department of Molecular Biology & Biotechnology, University of Kalyani, Kalyani, West Bengal, India
| | - Utpal Basu
- Department of Molecular Biology & Biotechnology, University of Kalyani, Kalyani, West Bengal, India
- * E-mail:
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Gutpell KM, Hrinivich WT, Hoffman LM. Skeletal muscle fibrosis in the mdx/utrn+/- mouse validates its suitability as a murine model of Duchenne muscular dystrophy. PLoS One 2015; 10:e0117306. [PMID: 25607927 PMCID: PMC4301874 DOI: 10.1371/journal.pone.0117306] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 12/22/2014] [Indexed: 12/31/2022] Open
Abstract
Various therapeutic approaches have been studied for the treatment of Duchenne muscular dystrophy (DMD), but none of these approaches have led to significant long-term effects in patients. One reason for this observed inefficacy may be the use of inappropriate animal models for the testing of therapeutic agents. The mdx mouse is the most widely used murine model of DMD, yet it does not model the fibrotic progression observed in patients. Other murine models of DMD are available that lack one or both alleles of utrophin, a functional analog of dystrophin. The aim of this study was to compare fibrosis and myofiber damage in the mdx, mdx/utrn+/- and double knockout (dko) mouse models. We used Masson’s trichrome stain and percentage of centrally-nucleated myofibers as indicators of fibrosis and myofiber regeneration, respectively, to assess disease progression in diaphragm and gastrocnemius muscles harvested from young and aged wild-type, mdx, mdx/utrn+/- and dko mice. Our results indicated that eight week-old gastrocnemius muscles of both mdx/utrn+/- and dko hind limb developed fibrosis whereas age-matched mdx gastrocnemius muscle did not (p = 0.002). The amount of collagen found in the mdx/utrn+/- diaphragm was significantly higher than that found in the corresponding diaphragm muscles of wild-type animals, but not of mdx animals (p = 0.0003). Aged mdx/utrn+/- mice developed fibrosis in both diaphragm and gastrocnemius muscles compared to wild-type controls (p = 0.003). Mdx diaphragm was fibrotic in aged mice as well (p = 0.0235), whereas the gastrocnemius muscle in these animals was not fibrotic. We did not measure a significant difference in collagen staining between wild-type and mdx gastrocnemius muscles. The results of this study support previous reports that the moderately-affected mdx/utrn+/- mouse is a better model of DMD, and we show here that this difference is apparent by 2 months of age.
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Affiliation(s)
- Kelly M. Gutpell
- Imaging Program, Lawson Health Research Institute, Department of Anatomy and Cell Biology, Western University, London, ON, Canada
- * E-mail:
| | | | - Lisa M. Hoffman
- Imaging Program, Lawson Health Research Institute, Department of Anatomy and Cell Biology, Western University, Department of Medical Biophysics, Western University, London, ON, Canada
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Lu A, Poddar M, Tang Y, Proto JD, Sohn J, Mu X, Oyster N, Wang B, Huard J. Rapid depletion of muscle progenitor cells in dystrophic mdx/utrophin-/- mice. Hum Mol Genet 2014; 23:4786-800. [PMID: 24781208 DOI: 10.1093/hmg/ddu194] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) patients lack dystrophin from birth; however, muscle weakness becomes apparent only at 3-5 years of age, which happens to coincide with the depletion of the muscle progenitor cell (MPC) pools. Indeed, MPCs isolated from older DMD patients demonstrate impairments in myogenic potential. To determine whether the progression of muscular dystrophy is a consequence of the decline in functional MPCs, we investigated two animal models of DMD: (i) dystrophin-deficient mdx mice, the most commonly utilized model of DMD, which has a relatively mild dystrophic phenotype and (ii) dystrophin/utrophin double knock-out (dKO) mice, which display a similar histopathologic phenotype to DMD patients. In contrast to age-matched mdx mice, we observed that both the number and regeneration potential of dKO MPCs rapidly declines during disease progression. This occurred in MPCs at both early and late stages of myogenic commitment. In fact, early MPCs isolated from 6-week-old dKO mice have reductions in proliferation, resistance to oxidative stress and multilineage differentiation capacities compared with age-matched mdx MPCs. This effect may potentially be mediated by fibroblast growth factor overexpression and/or a reduction in telomerase activity. Our results demonstrate that the rapid disease progression in the dKO model is associated, at least in part, with MPC depletion. Therefore, alleviating MPC depletion could represent an approach to delay the onset of the histopathologies associated with DMD patients.
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Affiliation(s)
- Aiping Lu
- Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Minakshi Poddar
- Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Ying Tang
- Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Jonathan D Proto
- Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Jihee Sohn
- Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Xiaodong Mu
- Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Nicholas Oyster
- Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Bing Wang
- Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Johnny Huard
- Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15219, USA
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Janssen PML, Murray JD, Schill KE, Rastogi N, Schultz EJ, Tran T, Raman SV, Rafael-Fortney JA. Prednisolone attenuates improvement of cardiac and skeletal contractile function and histopathology by lisinopril and spironolactone in the mdx mouse model of Duchenne muscular dystrophy. PLoS One 2014; 9:e88360. [PMID: 24551095 PMCID: PMC3923790 DOI: 10.1371/journal.pone.0088360] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 01/13/2014] [Indexed: 11/18/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is an inherited disease that causes striated muscle weakness. Recently, we showed therapeutic effects of the combination of lisinopril (L), an angiotensin converting enzyme (ACE) inhibitor, and spironolactone (S), an aldosterone antagonist, in mice lacking dystrophin and haploinsufficient for utrophin (utrn(+/-);mdx, het mice); both cardiac and skeletal muscle function and histology were improved when these mice were treated early with LS. It was unknown to what extent LS treatment is effective in the most commonly used DMD murine model, the mdx mouse. In addition, current standard-of-care treatment for DMD is limited to corticosteroids. Therefore, potentially useful alternative or additive drugs need to be both compared directly to corticosteroids and tested in presence of corticosteroids. We evaluated the effectiveness of this LS combination in the mdx mouse model both compared with corticosteroid treatment (prednisolone, P) or in combination (LSP). We tested the additional combinatorial treatment containing the angiotensin II receptor blocker losartan (T), which is widely used to halt and treat the developing cardiac dysfunction in DMD patients as an alternative to an ACE inhibitor. Peak myocardial strain rate, assessed by magnetic resonance imaging, showed a negative impact of P, whereas in both diaphragm and extensor digitorum longus (EDL) muscle contractile function was not significantly impaired by P. Histologically, P generally increased cardiac damage, estimated by percentage area infiltrated by IgG as well as by collagen staining. In general, groups that only differed in the presence or absence of P (i.e. mdx vs. P, LS vs. LSP, and TS vs. TSP) demonstrated a significant detrimental impact of P on many assessed parameters, with the most profound impact on cardiac pathology.
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Affiliation(s)
- Paul M. L. Janssen
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, Ohio, United States of America
- Dorothy M. Davis Heart & Lung Institute, The Ohio State University, Columbus, Ohio, United States of America
- * E-mail: (PJ); (JR-F)
| | - Jason D. Murray
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, Ohio, United States of America
| | - Kevin E. Schill
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, Ohio, United States of America
| | - Neha Rastogi
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, Ohio, United States of America
| | - Eric J. Schultz
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, Ohio, United States of America
| | - Tam Tran
- Division of Cardiovascular Medicine, The Ohio State University, Columbus, Ohio, United States of America
| | - Subha V. Raman
- Division of Cardiovascular Medicine, The Ohio State University, Columbus, Ohio, United States of America
- Dorothy M. Davis Heart & Lung Institute, The Ohio State University, Columbus, Ohio, United States of America
| | - Jill A. Rafael-Fortney
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, Ohio, United States of America
- Dorothy M. Davis Heart & Lung Institute, The Ohio State University, Columbus, Ohio, United States of America
- * E-mail: (PJ); (JR-F)
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Berry SE, Andruszkiewicz P, Chun JL, Hong J. Nestin expression in end-stage disease in dystrophin-deficient heart: implications for regeneration from endogenous cardiac stem cells. Stem Cells Transl Med 2013; 2:848-61. [PMID: 24068741 DOI: 10.5966/sctm.2012-0174] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Nestin(+) cardiac stem cells differentiate into striated cells following myocardial infarct. Transplantation of exogenous stem cells into myocardium of a murine model for Duchenne muscular dystrophy (DMD) increased proliferation of endogenous nestin(+) stem cells and resulted in the appearance of nestin(+) striated cells. This correlated with, and may be responsible for, prevention of dilated cardiomyopathy. We examined nestin(+) stem cells in the myocardium of dystrophin/utrophin-deficient (mdx/utrn(-/-)) mice, a model for DMD. We found that 92% of nestin(+) interstitial cells expressed Flk-1, a marker present on cardiac progenitor cells that differentiate into the cardiac lineage, and that a subset expressed Sca-1, present on adult cardiac cells that become cardiomyocytes. Nestin(+) interstitial cells maintained expression of Flk-1 but lost Sca-1 expression with age and were present in lower numbers in dystrophin-deficient heart than in wild-type heart. Unexpectedly, large clusters of nestin(+) striated cells ranging in size from 20 to 250 cells and extending up to 500 μm were present in mdx/utrn(-/-) heart near the end stage of disease. These cells were also present in dystrophin-deficient mdx/utrn(+/-) and mdx heart but not wild-type heart. Nestin(+) striated cells expressed cardiac troponin I, desmin, and Connexin 43 and correlated with proinflammatory CD68(+) macrophages. Elongated nestin(+) interstitial cells with striations were observed that did not express Flk-1 or the late cardiac marker cardiac troponin I but strongly expressed the early cardiac marker desmin. Nestin was also detected in endothelial and smooth muscle cells. These data indicate that new cardiomyocytes form in dystrophic heart, and nestin(+) interstitial cells may generate them in addition to other cells of the cardiac lineage.
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MESH Headings
- Animals
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Antigens, Differentiation, Myelomonocytic/genetics
- Antigens, Differentiation, Myelomonocytic/metabolism
- Antigens, Ly/genetics
- Antigens, Ly/metabolism
- Biomarkers/metabolism
- Connexin 43/genetics
- Connexin 43/metabolism
- Disease Models, Animal
- Dystrophin/deficiency
- Dystrophin/genetics
- Dystrophin/metabolism
- Endothelial Cells/metabolism
- Endothelial Cells/physiology
- Heart/physiopathology
- Macrophages/metabolism
- Macrophages/physiology
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Mice
- Mice, Inbred C57BL
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/metabolism
- Muscular Dystrophy, Duchenne/pathology
- Muscular Dystrophy, Duchenne/physiopathology
- Myocardial Infarction/genetics
- Myocardial Infarction/metabolism
- Myocardial Infarction/pathology
- Myocardial Infarction/physiopathology
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/physiology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/physiology
- Nestin/biosynthesis
- Nestin/genetics
- Nestin/metabolism
- Regeneration/genetics
- Regeneration/physiology
- Stem Cells/metabolism
- Stem Cells/physiology
- Utrophin/deficiency
- Utrophin/genetics
- Utrophin/metabolism
- Vascular Endothelial Growth Factor Receptor-2/genetics
- Vascular Endothelial Growth Factor Receptor-2/metabolism
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Johnson EK, Li B, Yoon JH, Flanigan KM, Martin PT, Ervasti J, Montanaro F. Identification of new dystroglycan complexes in skeletal muscle. PLoS One 2013; 8:e73224. [PMID: 23951345 PMCID: PMC3738564 DOI: 10.1371/journal.pone.0073224] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 07/18/2013] [Indexed: 01/16/2023] Open
Abstract
The dystroglycan complex contains the transmembrane protein β-dystroglycan and its interacting extracellular mucin-like protein α-dystroglycan. In skeletal muscle fibers, the dystroglycan complex plays an important structural role by linking the cytoskeletal protein dystrophin to laminin in the extracellular matrix. Mutations that affect any of the proteins involved in this structural axis lead to myofiber degeneration and are associated with muscular dystrophies and congenital myopathies. Because loss of dystrophin in Duchenne muscular dystrophy (DMD) leads to an almost complete loss of dystroglycan complexes at the myofiber membrane, it is generally assumed that the vast majority of dystroglycan complexes within skeletal muscle fibers interact with dystrophin. The residual dystroglycan present in dystrophin-deficient muscle is thought to be preserved by utrophin, a structural homolog of dystrophin that is up-regulated in dystrophic muscles. However, we found that dystroglycan complexes are still present at the myofiber membrane in the absence of both dystrophin and utrophin. Our data show that only a minority of dystroglycan complexes associate with dystrophin in wild type muscle. Furthermore, we provide evidence for at least three separate pools of dystroglycan complexes within myofibers that differ in composition and are differentially affected by loss of dystrophin. Our findings indicate a more complex role of dystroglycan in muscle than currently recognized and may help explain differences in disease pathology and severity among myopathies linked to mutations in DAPC members.
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Affiliation(s)
- Eric K. Johnson
- Center for Gene Therapy, the Research Institute at Nationwide Children’s Hospital, and The Ohio State University Biochemistry Program, Columbus, Ohio, United States of America
- Ohio State Biochemistry Program, the Ohio State University, Columbus, Ohio, United States of America
| | - Bin Li
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Jung Hae Yoon
- Center for Gene Therapy, the Research Institute at Nationwide Children’s Hospital, and The Ohio State University Biochemistry Program, Columbus, Ohio, United States of America
| | - Kevin M. Flanigan
- Center for Gene Therapy, the Research Institute at Nationwide Children’s Hospital, and The Ohio State University Biochemistry Program, Columbus, Ohio, United States of America
- Department of Pediatrics, the Ohio State University College of Medicine, Columbus, Ohio, United States of America
| | - Paul T. Martin
- Center for Gene Therapy, the Research Institute at Nationwide Children’s Hospital, and The Ohio State University Biochemistry Program, Columbus, Ohio, United States of America
- Department of Pediatrics, the Ohio State University College of Medicine, Columbus, Ohio, United States of America
| | - James Ervasti
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Federica Montanaro
- Center for Gene Therapy, the Research Institute at Nationwide Children’s Hospital, and The Ohio State University Biochemistry Program, Columbus, Ohio, United States of America
- Ohio State Biochemistry Program, the Ohio State University, Columbus, Ohio, United States of America
- Department of Pediatrics, the Ohio State University College of Medicine, Columbus, Ohio, United States of America
- * E-mail:
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Abstract
Duchenne muscular dystrophy (DMD) is a devastating progressive disease for which there is currently no effective treatment except palliative therapy. There are several promising genetic approaches, including viral delivery of the missing dystrophin gene, read-through of translation stop codons, exon skipping to restore the reading frame and increased expression of the compensatory utrophin gene. The lessons learned from these approaches will be applicable to many other disorders.
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Affiliation(s)
- Rebecca J Fairclough
- Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford OX1 3PT, UK
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Chun JL, O'Brien R, Song MH, Wondrasch BF, Berry SE. Injection of vessel-derived stem cells prevents dilated cardiomyopathy and promotes angiogenesis and endogenous cardiac stem cell proliferation in mdx/utrn-/- but not aged mdx mouse models for duchenne muscular dystrophy. Stem Cells Transl Med 2012; 2:68-80. [PMID: 23283493 DOI: 10.5966/sctm.2012-0107] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy. DMD patients lack dystrophin protein and develop skeletal muscle pathology and dilated cardiomyopathy (DCM). Approximately 20% succumb to cardiac involvement. We hypothesized that mesoangioblast stem cells (aorta-derived mesoangioblasts [ADMs]) would restore dystrophin and alleviate or prevent DCM in animal models of DMD. ADMs can be induced to express cardiac markers, including Nkx2.5, cardiac tropomyosin, cardiac troponin I, and α-actinin, and adopt cardiomyocyte morphology. Transplantation of ADMs into the heart of mdx/utrn(-/-) mice prior to development of DCM prevented onset of cardiomyopathy, as measured by echocardiography, and resulted in significantly higher CD31 expression, consistent with new vessel formation. Dystrophin-positive cardiomyocytes and increased proliferation of endogenous Nestin(+) cardiac stem cells were detected in ADM-injected heart. Nestin(+) striated cells were also detected in four of five mdx/utrn(-/-) hearts injected with ADMs. In contrast, when ADMs were injected into the heart of aged mdx mice with advanced fibrosis, no functional improvement was detected by echocardiography. Instead, ADMs exacerbated some features of DCM. No dystrophin protein, increase in CD31 expression, or increase in Nestin(+) cell proliferation was detected following ADM injection in aged mdx heart. Dystrophin was observed following transplantation of ADMs into the hearts of young mdx mice, however, suggesting that pathology in aged mdx heart may alter the fate of donor stem cells. In summary, ADMs delay or prevent development of DCM in dystrophin-deficient heart, but timing of stem cell transplantation may be critical for achieving benefit with cell therapy in DMD cardiac muscle.
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MESH Headings
- Age Factors
- Animals
- Antigens, Differentiation/metabolism
- Aorta/pathology
- Cardiomyopathy, Dilated/genetics
- Cardiomyopathy, Dilated/pathology
- Cardiomyopathy, Dilated/prevention & control
- Cell Proliferation
- Cells, Cultured
- Coronary Vessels/metabolism
- Coronary Vessels/physiopathology
- Disease Models, Animal
- Dystrophin/metabolism
- Humans
- Intermediate Filament Proteins/metabolism
- Mice
- Mice, Inbred mdx
- Mice, Knockout
- Muscular Dystrophy, Duchenne/genetics
- Muscular Dystrophy, Duchenne/pathology
- Muscular Dystrophy, Duchenne/therapy
- Myocardium/metabolism
- Myocardium/pathology
- Myocytes, Cardiac/metabolism
- Neovascularization, Physiologic
- Nerve Tissue Proteins/metabolism
- Nestin
- Stem Cell Transplantation
- Stem Cells/metabolism
- Stem Cells/physiology
- Utrophin/genetics
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Affiliation(s)
- Ju Lan Chun
- Department of Animal Sciences, University of Illinois, Urbana, IL, USA
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Singh SM, Molas JF, Kongari N, Bandi S, Armstrong GS, Winder SJ, Mallela KM. Thermodynamic stability, unfolding kinetics, and aggregation of the N-terminal actin-binding domains of utrophin and dystrophin. Proteins 2012; 80:1377-92. [PMID: 22275054 PMCID: PMC3439503 DOI: 10.1002/prot.24033] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 12/21/2011] [Accepted: 01/02/2012] [Indexed: 12/12/2022]
Abstract
Muscular dystrophy (MD) is the most common genetic lethal disorder in children. Mutations in dystrophin trigger the most common form of MD, Duchenne, and its allelic variant Becker MD. Utrophin is the closest homologue and has been shown to compensate for the loss of dystrophin in human disease animal models. However, the structural and functional similarities and differences between utrophin and dystrophin are less understood. Both proteins interact with actin through their N-terminal actin-binding domain (N-ABD). In this study, we examined the thermodynamic stability and aggregation of utrophin N-ABD and compared with that of dystrophin. Our results show that utrophin N-ABD has spectroscopic properties similar to dystrophin N-ABD. However, utrophin N-ABD has decreased denaturant and thermal stability, unfolds faster, and is correspondingly more susceptible to proteolysis, which might account for its decreased in vivo half-life compared to dystrophin. In addition, utrophin N-ABD aggregates to a lesser extent compared with dystrophin N-ABD, contrary to the general behavior of proteins in which decreased stability enhances protein aggregation. Despite these differences in stability and aggregation, both proteins exhibit deleterious effects of mutations. When utrophin N-ABD mutations analogous in position to the dystrophin disease-causing mutations were generated, they behaved similarly to dystrophin mutants in terms of decreased stability and the formation of cross-β aggregates, indicating a possible role for utrophin mutations in disease mechanisms.
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Affiliation(s)
- Surinder M. Singh
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, USA
| | - Justine F. Molas
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, USA
| | - Narsimulu Kongari
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, USA
| | - Swati Bandi
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, USA
| | - Geoffrey S. Armstrong
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, Colorado 80309, USA
| | - Steve J. Winder
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Krishna M.G. Mallela
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, USA
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Abstract
BACKGROUND Utrophin is the autosomal homolog of dystrophin, the product of the Duchenne Muscular Dystrophy (DMD) locus. Its regulation is of therapeutic interest as its overexpression can compensate for dystrophin's absence in animal models of DMD. The tissue distribution and transcriptional regulation of utrophin have been characterized extensively, and more recently translational control mechanisms that may underlie its complex expression patterns have begun to be identified. METHODOLOGY/PRINCIPAL FINDINGS Using a variety of bioinformatic, molecular and cell biology techniques, we show that the muscle isoform utrophin-A is predominantly suppressed at the translational level in C2C12 myoblasts. The extent of translational inhibition is estimated to be ~99% in C2C12 cells and is mediated by both the 5'- and 3'-UTRs of the utrophin-A mRNA. In this study we identify five miRNAs (let-7c, miR-150, miR-196b, miR-296-5p, miR-133b) that mediate the repression, and confirm repression by the previously identified miR-206. We demonstrate that this translational repression can be overcome by blocking the actions of miRNAs, resulting in an increased level of utrophin protein in C2C12 cells. CONCLUSIONS/SIGNIFICANCE The present study has identified key inhibitory mechanisms featuring miRNAs that regulate utrophin expression, and demonstrated that these mechanisms can be targeted to increase endogenous utrophin expression in cultured muscle cells. We suggest that miRNA-mediated inhibitory mechanisms could be targeted by methods similar to those described here as a novel strategy to increase utrophin expression as a therapy for DMD.
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Affiliation(s)
- Utpal Basu
- Department of Physiology, Pennsylvania Muscle Institute, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Olga Lozynska
- Department of Physiology, Pennsylvania Muscle Institute, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Catherine Moorwood
- Department of Physiology, Pennsylvania Muscle Institute, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Gopal Patel
- Department of Physiology, Pennsylvania Muscle Institute, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Steve D. Wilton
- Centre for Neuromuscular and Neurological Disorders, University of Western Australia, Perth, Australia
| | - Tejvir S. Khurana
- Department of Physiology, Pennsylvania Muscle Institute, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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Moorwood C, Lozynska O, Suri N, Napper AD, Diamond SL, Khurana TS. Drug discovery for Duchenne muscular dystrophy via utrophin promoter activation screening. PLoS One 2011; 6:e26169. [PMID: 22028826 PMCID: PMC3197614 DOI: 10.1371/journal.pone.0026169] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 09/21/2011] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Duchenne muscular dystrophy (DMD) is a devastating muscle wasting disease caused by mutations in dystrophin, a muscle cytoskeletal protein. Utrophin is a homologue of dystrophin that can functionally compensate for its absence when expressed at increased levels in the myofibre, as shown by studies in dystrophin-deficient mice. Utrophin upregulation is therefore a promising therapeutic approach for DMD. The use of a small, drug-like molecule to achieve utrophin upregulation offers obvious advantages in terms of delivery and bioavailability. Furthermore, much of the time and expense involved in the development of a new drug can be eliminated by screening molecules that are already approved for clinical use. METHODOLOGY/PRINCIPAL FINDINGS We developed and validated a cell-based, high-throughput screening assay for utrophin promoter activation, and used it to screen the Prestwick Chemical Library of marketed drugs and natural compounds. Initial screening produced 20 hit molecules, 14 of which exhibited dose-dependent activation of the utrophin promoter and were confirmed as hits. Independent validation demonstrated that one of these compounds, nabumetone, is able to upregulate endogenous utrophin mRNA and protein, in C2C12 muscle cells. CONCLUSIONS/SIGNIFICANCE We have developed a cell-based, high-throughput screening utrophin promoter assay. Using this assay, we identified and validated a utrophin promoter-activating drug, nabumetone, for which pharmacokinetics and safety in humans are already well described, and which represents a lead compound for utrophin upregulation as a therapy for DMD.
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Affiliation(s)
- Catherine Moorwood
- Department of Physiology and Pennsylvania Muscle Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Olga Lozynska
- Penn Center for Molecular Discovery, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Neha Suri
- Department of Physiology and Pennsylvania Muscle Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Andrew D. Napper
- Penn Center for Molecular Discovery, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Scott L. Diamond
- Penn Center for Molecular Discovery, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Tejvir S. Khurana
- Department of Physiology and Pennsylvania Muscle Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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Wehling-Henricks M, Tidball JG. Neuronal nitric oxide synthase-rescue of dystrophin/utrophin double knockout mice does not require nNOS localization to the cell membrane. PLoS One 2011; 6:e25071. [PMID: 22003386 PMCID: PMC3189177 DOI: 10.1371/journal.pone.0025071] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 08/26/2011] [Indexed: 02/03/2023] Open
Abstract
Survival of dystrophin/utrophin double-knockout (dko) mice was increased by muscle-specific expression of a neuronal nitric oxide synthase (nNOS) transgene. Dko mice expressing the transgene (nNOS TG+/dko) experienced delayed onset of mortality and increased life-span. The nNOS TG+/dko mice demonstrated a significant decrease in the concentration of CD163+, M2c macrophages that can express arginase and promote fibrosis. The decrease in M2c macrophages was associated with a significant reduction in fibrosis of heart, diaphragm and hindlimb muscles of nNOS TG+/dko mice. The nNOS transgene had no effect on the concentration of cytolytic, CD68+, M1 macrophages. Accordingly, we did not observe any change in the extent of muscle fiber lysis in the nNOS TG+/dko mice. These findings show that nNOS/NO (nitric oxide)-mediated decreases in M2c macrophages lead to a reduction in the muscle fibrosis that is associated with increased mortality in mice lacking dystrophin and utrophin. Interestingly, the dramatic and beneficial effects of the nNOS transgene were not attributable to localization of nNOS protein at the cell membrane. We did not detect any nNOS protein at the sarcolemma in nNOS TG+/dko muscles. This important observation shows that sarcolemmal localization is not necessary for nNOS to have beneficial effects in dystrophic tissue and the presence of nNOS in the cytosol of dystrophic muscle fibers can ameliorate the pathology and most importantly, significantly increase life-span.
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Affiliation(s)
- Michelle Wehling-Henricks
- Department of Integrative Biology and Physiology, University of California, Los Angeles, California, United States of America
| | - James G. Tidball
- Department of Integrative Biology and Physiology, University of California, Los Angeles, California, United States of America
- Molecular, Cellular and Integrative Physiology Program, University of California, Los Angeles, California, United States of America
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, California, United States of America
- * E-mail:
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Tinsley JM, Fairclough RJ, Storer R, Wilkes FJ, Potter AC, Squire SE, Powell DS, Cozzoli A, Capogrosso RF, Lambert A, Wilson FX, Wren SP, De Luca A, Davies KE. Daily treatment with SMTC1100, a novel small molecule utrophin upregulator, dramatically reduces the dystrophic symptoms in the mdx mouse. PLoS One 2011; 6:e19189. [PMID: 21573153 PMCID: PMC3089598 DOI: 10.1371/journal.pone.0019189] [Citation(s) in RCA: 137] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Accepted: 03/22/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Duchenne muscular dystrophy (DMD) is a lethal, progressive muscle wasting disease caused by a loss of sarcolemmal bound dystrophin, which results in the death of the muscle fibers leading to the gradual depletion of skeletal muscle. There is significant evidence demonstrating that increasing levels of the dystrophin-related protein, utrophin, in mouse models results in sarcolemmal bound utrophin and prevents the muscular dystrophy pathology. The aim of this work was to develop a small molecule which increases the levels of utrophin in muscle and thus has therapeutic potential. METHODOLOGY AND PRINCIPAL FINDINGS We describe the in vivo activity of SMT C1100; the first orally bioavailable small molecule utrophin upregulator. Once-a-day daily-dosing with SMT C1100 reduces a number of the pathological effects of dystrophin deficiency. Treatment results in reduced pathology, better muscle physiology leading to an increase in overall strength, and an ability to resist fatigue after forced exercise; a surrogate for the six minute walk test currently recommended as the pivotal outcome measure in human trials for DMD. CONCLUSIONS AND SIGNIFICANCE This study demonstrates proof-of-principle for the use of in vitro screening methods in allowing identification of pharmacological agents for utrophin transcriptional upregulation. The best compound identified, SMT C1100, demonstrated significant disease modifying effects in DMD models. Our data warrant the full evaluation of this compound in clinical trials in DMD patients.
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Affiliation(s)
| | - Rebecca J. Fairclough
- MRC Functional Genomics Unit, Department of Physiology Anatomy and
Genetics, University of Oxford, Oxford, United Kingdom
| | | | | | - Allyson C. Potter
- MRC Functional Genomics Unit, Department of Physiology Anatomy and
Genetics, University of Oxford, Oxford, United Kingdom
| | - Sarah E. Squire
- MRC Functional Genomics Unit, Department of Physiology Anatomy and
Genetics, University of Oxford, Oxford, United Kingdom
| | - Dave S. Powell
- MRC Functional Genomics Unit, Department of Physiology Anatomy and
Genetics, University of Oxford, Oxford, United Kingdom
| | - Anna Cozzoli
- Unit of Pharmacology, Department of Pharmaco-biology, University of Bari
“A. Moro”, Bari, Italy
| | - Roberta F. Capogrosso
- Unit of Pharmacology, Department of Pharmaco-biology, University of Bari
“A. Moro”, Bari, Italy
| | | | | | | | - Annamaria De Luca
- Unit of Pharmacology, Department of Pharmaco-biology, University of Bari
“A. Moro”, Bari, Italy
| | - Kay E. Davies
- MRC Functional Genomics Unit, Department of Physiology Anatomy and
Genetics, University of Oxford, Oxford, United Kingdom
- * E-mail: (JMT); (KED)
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Li D, Bareja A, Judge L, Yue Y, Lai Y, Fairclough R, Davies KE, Chamberlain JS, Duan D. Sarcolemmal nNOS anchoring reveals a qualitative difference between dystrophin and utrophin. J Cell Sci 2010; 123:2008-13. [PMID: 20483958 PMCID: PMC2880012 DOI: 10.1242/jcs.064808] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2010] [Indexed: 01/02/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a lethal muscle disease caused by dystrophin deficiency. In normal muscle, dystrophin helps maintain sarcolemmal stability. Dystrophin also recruits neuronal nitric oxide synthase (nNOS) to the sarcolemma. Failure to anchor nNOS to the membrane leads to functional ischemia and aggravates muscle disease in DMD. Over the past two decades, a great variety of therapeutic modalities have been explored to treat DMD. A particularly attractive approach is to increase utrophin expression. Utrophin shares considerable sequence, structural and functional similarity with dystrophin. Here, we test the hypothesis that utrophin also brings nNOS to the sarcolemma. Full-length utrophin cDNA was expressed in dystrophin-deficient mdx mice by gutted adenovirus or via transgenic overexpression. Subcellular nNOS localization was determined by immunofluorescence staining, in situ nNOS activity staining and microsomal preparation western blot. Despite supra-physiological utrophin expression, we did not detect nNOS at the sarcolemma. Furthermore, transgenic utrophin overexpression failed to protect mdx muscle from exercise-associated injury. Our results suggest that full-length utrophin cannot anchor nNOS to the sarcolemma. This finding might have important implications for the development of utrophin-based DMD therapies.
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Affiliation(s)
- Dejia Li
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, MO 65212, USA
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Abstract
Zinc finger (ZF) proteins belonging to the Cys2-His2 class provide a simple and versatile framework to design novel artificial transcription factors (ATFs) targeted to the desired genes. Our work is based on ZF ATFs engineered to up-regulate the expression level of the dystrophin-related gene utrophin in Duchenne muscular dystrophy (DMD). In particular, on the basis of the "recognition code" that defines specific rules between zinc finger primary structure and potential DNA-binding sites we engineered and selected a new family of artificial transcription factors, whose DNA-binding domain consists in a three zinc finger peptide called "Jazz." Jazz protein binds specifically the 9 bp DNA sequence (5(')-GCT-GCT-GCG-3(')) present in the promoter region of both the human and mouse utrophin gene. We generated a transgenic mouse expressing Jazz protein fused to the strong transcriptional activation domain VP16 and under the control of the muscle specific promoter of the myosin light chain gene. Vp16-Jazz mice display a strong up-regulation of the utrophin at both mRNA and protein levels. To our knowledge, this represents the first example of a transgenic mouse expressing an artificial gene coding for a zinc finger-based transcription factor.
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Ahmad N, Bygrave M, Chhem R, Hoffman L, Welch I, Grange R, Fenster A, Hill D, Lee TY. High-frequency ultrasound to grade disease progression in murine models of Duchenne muscular dystrophy. J Ultrasound Med 2009; 28:707-716. [PMID: 19470810 DOI: 10.7863/jum.2009.28.6.707] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVE This study used high-frequency ultrasound (HFU) imaging to assess muscle damage noninvasively in a longitudinal study of 2 transgenic murine models of Duchenne muscular dystrophy (DMD): mdx, which has mutated cytoskeletal protein dystrophin; and udx, which has mutated dystrophin and lacks another cytoskeleton protein, utrophin. The mdx group was further subdivided into exercised and nonexercised subgroups to assess exercise-induced damage. METHODS Muscle damage was assessed with HFU imaging (40 MHz) at biweekly intervals for 16 weeks. The assessment was based on the number of hyperechoic lesions, the lesion diameter, and muscle disorganization, giving a combined grade according to a 5-point scale. RESULTS High-frequency ultrasound discriminated the severity of muscle damage between wild-type and transgenic models of DMD and between mdx and udx models. Qualitative comparisons of 3-dimensional HFU images with serial histologic sections of the skeletal muscle showed the ability of ultrasound to accurately depict changes seen in the muscle architecture in vivo. CONCLUSIONS High-frequency ultrasound images soft tissue in mice at high contrast and spatial resolution, thereby showing that this microimaging modality has the capability to assess architectural changes in muscle fibers due to myotonic dystrophy-related diseases such as DMD.
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MESH Headings
- Animals
- Disease Models, Animal
- Disease Progression
- Dystrophin/genetics
- Gene Deletion
- Imaging, Three-Dimensional
- Longitudinal Studies
- Mice
- Mice, Inbred mdx
- Mice, Transgenic
- Muscular Dystrophy, Animal/diagnostic imaging
- Muscular Dystrophy, Animal/genetics
- Muscular Dystrophy, Animal/physiopathology
- Muscular Dystrophy, Duchenne/diagnostic imaging
- Muscular Dystrophy, Duchenne/physiopathology
- Physical Conditioning, Animal
- Point Mutation
- Ultrasonography/methods
- Utrophin/genetics
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Affiliation(s)
- Nabeel Ahmad
- Imaging Research Laboratories, Robarts Research Institute, 100 Perth Dr, London, ON N6A 5K9, Canada
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Sonnemann KJ, Heun-Johnson H, Turner AJ, Baltgalvis KA, Lowe DA, Ervasti JM. Functional substitution by TAT-utrophin in dystrophin-deficient mice. PLoS Med 2009; 6:e1000083. [PMID: 19478831 PMCID: PMC2680620 DOI: 10.1371/journal.pmed.1000083] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Accepted: 04/22/2009] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The loss of dystrophin compromises muscle cell membrane stability and causes Duchenne muscular dystrophy and/or various forms of cardiomyopathy. Increased expression of the dystrophin homolog utrophin by gene delivery or pharmacologic up-regulation has been demonstrated to restore membrane integrity and improve the phenotype in the dystrophin-deficient mdx mouse. However, the lack of a viable therapy in humans predicates the need to explore alternative methods to combat dystrophin deficiency. We investigated whether systemic administration of recombinant full-length utrophin (Utr) or DeltaR4-21 "micro" utrophin (muUtr) protein modified with the cell-penetrating TAT protein transduction domain could attenuate the phenotype of mdx mice. METHODS AND FINDINGS Recombinant TAT-Utr and TAT-muUtr proteins were expressed using the baculovirus system and purified using FLAG-affinity chromatography. Age-matched mdx mice received six twice-weekly intraperitoneal injections of either recombinant protein or PBS. Three days after the final injection, mice were analyzed for several phenotypic parameters of dystrophin deficiency. Injected TAT-muUtr transduced all tissues examined, integrated with members of the dystrophin complex, reduced serum levels of creatine kinase (11,290+/-920 U versus 5,950+/-1,120 U; PBS versus TAT), the prevalence of muscle degeneration/regeneration (54%+/-5% versus 37%+/-4% of centrally nucleated fibers; PBS versus TAT), the susceptibility to eccentric contraction-induced force drop (72%+/-5% versus 40%+/-8% drop; PBS versus TAT), and increased specific force production (9.7+/-1.1 N/cm(2) versus 12.8+/-0.9 N/cm(2); PBS versus TAT). CONCLUSIONS These results are, to our knowledge, the first to establish the efficacy and feasibility of TAT-utrophin-based constructs as a novel direct protein-replacement therapy for the treatment of skeletal and cardiac muscle diseases caused by loss of dystrophin.
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Affiliation(s)
- Kevin J. Sonnemann
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Hanke Heun-Johnson
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Amy J. Turner
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Kristen A. Baltgalvis
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Dawn A. Lowe
- Program in Physical Therapy, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - James M. Ervasti
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, United States of America
- * E-mail:
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Banks GB, Chamberlain JS, Froehner SC. Truncated dystrophins can influence neuromuscular synapse structure. Mol Cell Neurosci 2009; 40:433-41. [PMID: 19171194 DOI: 10.1016/j.mcn.2008.12.011] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Revised: 12/12/2008] [Accepted: 12/16/2008] [Indexed: 11/18/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is characterized by muscle degeneration and structural defects in the neuromuscular synapse that are caused by mutations in dystrophin. Whether aberrant neuromuscular synapse structure is an indirect consequence of muscle degeneration or a direct result of loss of dystrophin function is not known. Rational design of truncated dystrophins has enabled the design of expression cassettes highly effective at preventing muscle degeneration in mouse models of DMD using gene therapy. Here we examined the functional capacity of a minidystrophin (minidysGFP) and a microdystrophin (microdystrophin(DeltaR4-R23)) transgene on the maturation and maintenance of neuromuscular junctions (NMJ) in mdx mice. We found that minidysGFP prevents fragmentation and the loss of postsynaptic folds at the NMJ. In contrast, microdystrophin (DeltaR4-R23) was unable to prevent synapse fragmentation in the limb muscles despite preventing muscle degeneration, although fragmentation was observed to temporally correlate with the formation of ringed fibers. Surprisingly, microdystrophin(DeltaR4-R23) increased the length of synaptic folds in the diaphragm muscles of mdx mice independent of muscle degeneration or the formation of ringed fibers. We also demonstrate that the number and depth of synaptic folds influences the density of voltage-gated sodium channels at the neuromuscular synapse in mdx, microdystrophin(DeltaR4-R23)/mdx and mdx:utrophin double knockout mice. Together, these data suggest that maintenance of the neuromuscular synapse is governed through its lateral association with the muscle cytoskeleton, and that dystrophin has a direct role in promoting the maturation of synaptic folds to allow more sodium channels into the junction.
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Affiliation(s)
- Glen B Banks
- Department of Neurology, Senator Paul D Wellstone Muscular Dystrophy Cooperative Research Center, University of Washington, Seattle, Washington 98195, USA.
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Miura P, Andrews M, Holcik M, Jasmin BJ. IRES-mediated translation of utrophin A is enhanced by glucocorticoid treatment in skeletal muscle cells. PLoS One 2008; 3:e2309. [PMID: 18545658 PMCID: PMC2396518 DOI: 10.1371/journal.pone.0002309] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Accepted: 04/25/2008] [Indexed: 11/18/2022] Open
Abstract
Glucocorticoids are currently the only drug treatment recognized to benefit Duchenne muscular dystrophy (DMD) patients. The nature of the mechanisms underlying the beneficial effects remains incompletely understood but may involve an increase in the expression of utrophin. Here, we show that treatment of myotubes with 6α−methylprednisolone-21 sodium succinate (PDN) results in enhanced expression of utrophin A without concomitant increases in mRNA levels thereby suggesting that translational regulation contributes to the increase. In agreement with this, we show that PDN treatment of cells transfected with monocistronic reporter constructs harbouring the utrophin A 5′UTR, causes an increase in reporter protein expression while leaving levels of reporter mRNAs unchanged. Using bicistronic reporter assays, we further demonstrate that PDN enhances activity of an Internal Ribosome Entry Site (IRES) located within the utrophin A 5′UTR. Analysis of polysomes demonstrate that PDN causes an overall reduction in polysome-associated mRNAs indicating that global translation rates are depressed under these conditions. Importantly, PDN causes an increase in the polysome association of endogenous utrophin A mRNAs and reporter mRNAs harbouring the utrophin A 5′UTR. Additional experiments identified a distinct region within the utrophin A 5′UTR that contains the inducible IRES activity. Together, these studies demonstrate that a translational regulatory mechanism involving increased IRES activation mediates, at least partially, the enhanced expression of utrophin A in muscle cells treated with glucocorticoids. Targeting the utrophin A IRES may thus offer an important and novel therapeutic avenue for developing drugs appropriate for DMD patients.
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Affiliation(s)
- Pedro Miura
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario, Canada
| | - Meghan Andrews
- Apoptosis Research Centre, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Martin Holcik
- Apoptosis Research Centre, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Bernard J. Jasmin
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Health Research Institute, Molecular Medicine Program, Ottawa Hospital, Ottawa, Onatario, Canada
- * E-mail:
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50
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Chakkalakal JV, Miura P, Bélanger G, Michel RN, Jasmin BJ. Modulation of utrophin A mRNA stability in fast versus slow muscles via an AU-rich element and calcineurin signaling. Nucleic Acids Res 2008; 36:826-38. [PMID: 18084024 PMCID: PMC2241908 DOI: 10.1093/nar/gkm1107] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Revised: 11/19/2007] [Accepted: 11/26/2007] [Indexed: 12/12/2022] Open
Abstract
We examined the role of post-transcriptional mechanisms in controlling utrophin A mRNA expression in slow versus fast skeletal muscles. First, we determined that the half-life of utrophin A mRNA is significantly shorter in the presence of proteins isolated from fast muscles. Direct plasmid injection experiments using reporter constructs containing the full-length or truncated variants of the utrophin 3'UTR into slow soleus and fast extensor digitorum longus muscles revealed that a region of 265 nucleotides is sufficient to confer lower levels of reporter mRNA in fast muscles. Further analysis of this region uncovered a conserved AU-rich element (ARE) that suppresses expression of reporter mRNAs in cultured muscle cells. Moreover, stability of reporter mRNAs fused to the utrophin full-length 3'UTR was lower in the presence of fast muscle protein extracts. This destabilization effect seen in vivo was lost upon deletion of the conserved ARE. Finally, we observed that calcineurin signaling affects utrophin A mRNA stability through the conserved ARE. These results indicate that ARE-mediated mRNA decay is a key mechanism that regulates expression of utrophin A mRNA in slow muscle fibers. This is the first demonstration of ARE-mediated mRNA decay regulating the expression of a gene associated with the slow myogenic program.
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Affiliation(s)
- Joe V. Chakkalakal
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada K1H 8M5, Department of Chemistry and Biochemistry, Department of Exercise Science and Centre for Structural and Functional Genomics, Concordia University, The Richard J. Renaud Science Complex, Montreal, QC, Canada H4B 1R6 and Ottawa Health Research Institute, Molecular Medicine Program, Ottawa Hospital, General Campus, Ottawa, ON, Canada K1H 8L6
| | - Pedro Miura
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada K1H 8M5, Department of Chemistry and Biochemistry, Department of Exercise Science and Centre for Structural and Functional Genomics, Concordia University, The Richard J. Renaud Science Complex, Montreal, QC, Canada H4B 1R6 and Ottawa Health Research Institute, Molecular Medicine Program, Ottawa Hospital, General Campus, Ottawa, ON, Canada K1H 8L6
| | - Guy Bélanger
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada K1H 8M5, Department of Chemistry and Biochemistry, Department of Exercise Science and Centre for Structural and Functional Genomics, Concordia University, The Richard J. Renaud Science Complex, Montreal, QC, Canada H4B 1R6 and Ottawa Health Research Institute, Molecular Medicine Program, Ottawa Hospital, General Campus, Ottawa, ON, Canada K1H 8L6
| | - Robin N. Michel
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada K1H 8M5, Department of Chemistry and Biochemistry, Department of Exercise Science and Centre for Structural and Functional Genomics, Concordia University, The Richard J. Renaud Science Complex, Montreal, QC, Canada H4B 1R6 and Ottawa Health Research Institute, Molecular Medicine Program, Ottawa Hospital, General Campus, Ottawa, ON, Canada K1H 8L6
| | - Bernard J. Jasmin
- Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada K1H 8M5, Department of Chemistry and Biochemistry, Department of Exercise Science and Centre for Structural and Functional Genomics, Concordia University, The Richard J. Renaud Science Complex, Montreal, QC, Canada H4B 1R6 and Ottawa Health Research Institute, Molecular Medicine Program, Ottawa Hospital, General Campus, Ottawa, ON, Canada K1H 8L6
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