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Nguyen MN, Hooper C, Stefanini M, Vrellaku B, Carnicer R, Wood MJ, Simon JN, Casadei B. Why is early-onset atrial fibrillation uncommon in patients with Duchenne muscular dystrophy? Insights from the mdx mouse. Cardiovasc Res 2024; 120:519-530. [PMID: 38270932 PMCID: PMC11060487 DOI: 10.1093/cvr/cvae022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Accepted: 01/08/2024] [Indexed: 01/26/2024] Open
Abstract
AIMS A reduction in both dystrophin and neuronal nitric oxide synthase (NOS1) secondary to microRNA-31 (miR-31) up-regulation contributes to the atrial electrical remodelling that underpins human and experimental atrial fibrillation (AF). In contrast, patients with Duchenne muscular dystrophy (DMD), who lack dystrophin and NOS1 and, at least in the skeletal muscle, have raised miR-31 expression, do not have increase susceptibility to AF in the absence of left ventricular (LV) dysfunction. Here, we investigated whether dystrophin deficiency is also associated with atrial up-regulation of miR-31, loss of NOS1 protein, and increased AF susceptibility in young mdx mice. METHODS AND RESULTS Echocardiography showed normal cardiac structure and function in 12-13 weeks mdx mice, with no indication by assay of hydroxyproline that atrial fibrosis had developed. The absence of dystrophin in mdx mice was accompanied by an overall reduction in syntrophin and a lower NOS1 protein content in the skeletal muscle and in the left atrial and ventricular myocardium, with the latter occurring alongside reduced Nos1 transcript levels (exons 1-2 by quantitative polymerase chain reaction) and an increase in NOS1 polyubiquitination [assessed using tandem polyubiquitination pulldowns; P < 0.05 vs. wild type (WT)]. Neither the up-regulation of miR-31 nor the substantial reduction in NOS activity observed in the skeletal muscle was present in the atrial tissue of mdx mice. At difference with the skeletal muscle, the mdx atrial myocardium showed a reduction in the constitutive NOS inhibitor, caveolin-1, coupled with an increase in NOS3 serine1177 phosphorylation, in the absence of differences in the protein content of other NOS isoforms or in the relative expression NOS1 splice variants. In line with these findings, transoesophageal atrial burst pacing revealed no difference in AF susceptibility between mdx mice and their WT littermates. CONCLUSION Dystrophin depletion is not associated with atrial miR-31 up-regulation, reduced NOS activity, or increased AF susceptibility in the mdx mouse. Compared with the skeletal muscle, the milder atrial biochemical phenotype may explain why patients with DMD do not exhibit a higher prevalence of atrial arrhythmias despite a reduction in NOS1 content.
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Affiliation(s)
- My-Nhan Nguyen
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, L6 West Wing, Oxford OX3 9DU, UK
| | - Charlotte Hooper
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, L6 West Wing, Oxford OX3 9DU, UK
| | - Matilde Stefanini
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, L6 West Wing, Oxford OX3 9DU, UK
| | - Besarte Vrellaku
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, L6 West Wing, Oxford OX3 9DU, UK
| | - Ricardo Carnicer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, L6 West Wing, Oxford OX3 9DU, UK
| | - Matthew J Wood
- Department of Paediatrics and Muscular Dystrophy UK Oxford Neuromuscular Centre, University of Oxford, Oxford, UK
| | - Jillian N Simon
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, L6 West Wing, Oxford OX3 9DU, UK
| | - Barbara Casadei
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, L6 West Wing, Oxford OX3 9DU, UK
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2
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Elasbali AM, Al-Soud WA, Anwar S, Alhassan HH, Adnan M, Hassan MI. A review on mechanistic insights into structure and function of dystrophin protein in pathophysiology and therapeutic targeting of Duchenne muscular dystrophy. Int J Biol Macromol 2024; 264:130544. [PMID: 38428778 DOI: 10.1016/j.ijbiomac.2024.130544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/09/2024] [Accepted: 02/28/2024] [Indexed: 03/03/2024]
Abstract
Duchenne Muscular Dystrophy (DMD) is an X-linked recessive genetic disorder characterized by progressive and severe muscle weakening and degeneration. Among the various forms of muscular dystrophy, it stands out as one of the most common and impactful, predominantly affecting boys. The condition arises due to mutations in the dystrophin gene, a key player in maintaining the structure and function of muscle fibers. The manuscript explores the structural features of dystrophin protein and their pivotal roles in DMD. We present an in-depth analysis of promising therapeutic approaches targeting dystrophin and their implications for the therapeutic management of DMD. Several therapies aiming to restore dystrophin protein or address secondary pathology have obtained regulatory approval, and many others are ongoing clinical development. Notably, recent advancements in genetic approaches have demonstrated the potential to restore partially functional dystrophin forms. The review also provides a comprehensive overview of the status of clinical trials for major therapeutic genetic approaches for DMD. In addition, we have summarized the ongoing therapeutic approaches and advanced mechanisms of action for dystrophin restoration and the challenges associated with DMD therapeutics.
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Affiliation(s)
- Abdelbaset Mohamed Elasbali
- Department of Clinical Laboratory Science, College of Applied Medical Sciences-Qurayyat, Jouf University, Saudi Arabia
| | - Waleed Abu Al-Soud
- Department of Clinical Laboratory Science, College of Applied Sciences-Sakaka, Jouf University, Sakaka, Saudi Arabia; Molekylärbiologi, Klinisk Mikrobiologi och vårdhygien, Region Skåne, Sölvegatan 23B, 221 85 Lund, Sweden
| | - Saleha Anwar
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India
| | - Hassan H Alhassan
- Department of Clinical Laboratory Science, College of Applied Sciences-Sakaka, Jouf University, Sakaka, Saudi Arabia
| | - Mohd Adnan
- Department of Biology, College of Science, University of Ha'il, Ha'il, Saudi Arabia
| | - Md Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India.
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3
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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] [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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4
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Albini S, Palmieri L, Dubois A, Bourg N, Lostal W, Richard I. Assessment of Therapeutic Potential of a Dual AAV Approach for Duchenne Muscular Dystrophy. Int J Mol Sci 2023; 24:11421. [PMID: 37511179 PMCID: PMC10380683 DOI: 10.3390/ijms241411421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 06/27/2023] [Accepted: 06/30/2023] [Indexed: 07/30/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a yet incurable rare genetic disease that affects the skeletal and cardiac muscles, leading to progressive muscle wasting and premature death. DMD is caused by the lack of dystrophin, a muscle protein essential for the biochemical support and integrity of muscle fibers. Gene replacement strategies for Duchenne muscular dystrophy (DMD) employing the adeno-associated virus (AAV) face the challenge imposed by the limited packaging capacity of AAV, only allowing the accommodation of a short version of dystrophin (µDys) that is still far removed from correcting human disease. The need to develop strategies leading to the expression of a best performing dystrophin variant led to only few studies reporting on the use of dual vectors, but none reported on a method to assess in vivo transgene reconstitution efficiency, the degree of which directly affects the use of safe AAV dosing. We report here on the generation of a dual AAV vector approach for the expression of a larger dystrophin version (quasidystrophin) based on homologous recombination, and the development of a methodology employing a strategic droplet digital PCR design, to determine the recombination efficiency as well as the occurrence of unwanted concatemerization events or aberrant expression from the single vectors. We demonstrated that, upon systemic delivery in the dystrophic D2.B10-Dmdmdx/J (DBA2mdx) mice, our dual AAV approach led to high transgene reconstitution efficiency and negligible Inverted Terminal Repeats (ITR)-dependent concatemerization, with consequent remarkable protein restoration in muscles and improvement of muscle pathology. This evidence supports the suitability of our system for gene therapy application and the potential of this methodology to assess and improve the feasibility for therapeutic translation of multiple vector approaches.
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Affiliation(s)
- Sonia Albini
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - Laura Palmieri
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - Auriane Dubois
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - Nathalie Bourg
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - William Lostal
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - Isabelle Richard
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
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5
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Hamm SE, Yuan C, McQueen LF, Wallace MA, Zhang H, Arora A, Garafalo AM, McMillan RP, Lawlor MW, Prom MJ, Ott EM, Yan J, Addington AK, Morris CA, Gonzalez JP, Grange RW. Prolonged voluntary wheel running reveals unique adaptations in mdx mice treated with microdystrophin constructs ± the nNOS-binding site. Front Physiol 2023; 14:1166206. [PMID: 37435312 PMCID: PMC10330712 DOI: 10.3389/fphys.2023.1166206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 05/10/2023] [Indexed: 07/13/2023] Open
Abstract
We tested the effects of prolonged voluntary wheel running on the muscle function of mdx mice treated with one of two different microdystrophin constructs. At 7 weeks of age mdx mice were injected with a single dose of AAV9-CK8-microdystrophin with (gene therapy 1, GT1) or without (gene therapy 2, GT2) the nNOS-binding domain and were assigned to one of four gene therapy treated groups: mdxRGT1 (run, GT1), mdxGT1 (no run, GT1), or mdxRGT2 (run,GT2), mdxGT2 (no run, GT2). There were two mdx untreated groups injected with excipient: mdxR (run, no gene therapy) and mdx (no run, no gene therapy). A third no treatment group, Wildtype (WT) received no injection and did not run. mdxRGT1, mdxRGT2 and mdxR performed voluntary wheel running for 52 weeks; WT and remaining mdx groups were cage active. Robust expression of microdystrophin occurred in diaphragm, quadriceps, and heart muscles of all treated mice. Dystrophic muscle pathology was high in diaphragms of non-treated mdx and mdxR mice and improved in all treated groups. Endurance capacity was rescued by both voluntary wheel running and gene therapy alone, but their combination was most beneficial. All treated groups increased in vivo plantarflexor torque over both mdx and mdxR mice. mdx and mdxR mice displayed ∼3-fold lower diaphragm force and power compared to WT values. Treated groups demonstrated partial improvements in diaphragm force and power, with mdxRGT2 mice experiencing the greatest improvement at ∼60% of WT values. Evaluation of oxidative red quadriceps fibers revealed the greatest improvements in mitochondrial respiration in mdxRGT1 mice, reaching WT levels. Interestingly, mdxGT2 mice displayed diaphragm mitochondrial respiration values similar to WT but mdxRGT2 animals showed relative decreases compared to the no run group. Collectively, these data demonstrate that either microdystrophin construct combined with voluntary wheel running increased in vivo maximal muscle strength, power, and endurance. However, these data also highlighted important differences between the two microdystrophin constructs. GT1, with the nNOS-binding site, improved more markers of exercise-driven adaptations in metabolic enzyme activity of limb muscles, while GT2, without the nNOS-binding site, demonstrated greater protection of diaphragm strength after chronic voluntary endurance exercise but decreased mitochondrial respiration in the context of running.
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Affiliation(s)
- S. E. Hamm
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
| | - C. Yuan
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
| | - L. F. McQueen
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
| | - M. A. Wallace
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
| | - H. Zhang
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
| | - A. Arora
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
| | - A. M. Garafalo
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
| | - R. P. McMillan
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
| | - M. W. Lawlor
- Department of Pathology and Neuroscience Research Center, Medical College of Wisconsin and Diverge Translational Science Laboratory, Milwaukee, WI, United States
| | - M. J. Prom
- Department of Pathology and Neuroscience Research Center, Medical College of Wisconsin and Diverge Translational Science Laboratory, Milwaukee, WI, United States
| | - E. M. Ott
- Department of Pathology and Neuroscience Research Center, Medical College of Wisconsin and Diverge Translational Science Laboratory, Milwaukee, WI, United States
| | - J. Yan
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
| | - A. K. Addington
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
| | - C. A. Morris
- Solid Biosciences, Inc., Cambridge, MA, United States
| | | | - R. W. Grange
- Department of Human Nutrition, Foods and Exercise and Metabolism Core, Virginia Tech, Blacksburg, VA, United States
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6
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Mirouse V. Evolution and developmental functions of the dystrophin-associated protein complex: beyond the idea of a muscle-specific cell adhesion complex. Front Cell Dev Biol 2023; 11:1182524. [PMID: 37384252 PMCID: PMC10293626 DOI: 10.3389/fcell.2023.1182524] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 05/30/2023] [Indexed: 06/30/2023] Open
Abstract
The Dystrophin-Associated Protein Complex (DAPC) is a well-defined and evolutionarily conserved complex in animals. DAPC interacts with the F-actin cytoskeleton via dystrophin, and with the extracellular matrix via the membrane protein dystroglycan. Probably for historical reasons that have linked its discovery to muscular dystrophies, DAPC function is often described as limited to muscle integrity maintenance by providing mechanical robustness, which implies strong cell-extracellular matrix adhesion properties. In this review, phylogenetic and functional data from different vertebrate and invertebrate models will be analyzed and compared to explore the molecular and cellular functions of DAPC, with a specific focus on dystrophin. These data reveals that the evolution paths of DAPC and muscle cells are not intrinsically linked and that many features of dystrophin protein domains have not been identified yet. DAPC adhesive properties also are discussed by reviewing the available evidence of common key features of adhesion complexes, such as complex clustering, force transmission, mechanosensitivity and mechanotransduction. Finally, the review highlights DAPC developmental roles in tissue morphogenesis and basement membrane (BM) assembly that may indicate adhesion-independent functions.
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7
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Cernisova V, Lu-Nguyen N, Trundle J, Herath S, Malerba A, Popplewell L. Microdystrophin Gene Addition Significantly Improves Muscle Functionality and Diaphragm Muscle Histopathology in a Fibrotic Mouse Model of Duchenne Muscular Dystrophy. Int J Mol Sci 2023; 24:ijms24098174. [PMID: 37175881 PMCID: PMC10179398 DOI: 10.3390/ijms24098174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/26/2023] [Accepted: 04/28/2023] [Indexed: 05/15/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a rare neuromuscular disease affecting 1:5000 newborn males. No cure is currently available, but gene addition therapy, based on the adeno-associated viral (AAV) vector-mediated delivery of microdystrophin transgenes, is currently being tested in clinical trials. The muscles of DMD boys present significant fibrotic and adipogenic tissue deposition at the time the treatment starts. The presence of fibrosis not only worsens the disease pathology, but also diminishes the efficacy of gene therapy treatments. To gain an understanding of the efficacy of AAV-based microdystrophin gene addition in a relevant, fibrotic animal model of DMD, we conducted a systemic study in juvenile D2.mdx mice using the single intravenous administration of an AAV8 system expressing a sequence-optimized murine microdystrophin, named MD1 (AAV8-MD1). We mainly focused our study on the diaphragm, a respiratory muscle that is crucial for DMD pathology and that has never been analyzed after treatment with AAV-microdystrophin in this mouse model. We provide strong evidence here that the delivery of AAV8-MD1 provides significant improvement in body-wide muscle function. This is associated with the protection of the hindlimb muscle from contraction-induced damage and the prevention of fibrosis deposition in the diaphragm muscle. Our work corroborates the observation that the administration of gene therapy in DMD is beneficial in preventing muscle fibrosis.
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Affiliation(s)
- Viktorija Cernisova
- Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Ngoc Lu-Nguyen
- Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Jessica Trundle
- Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Shan Herath
- Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Alberto Malerba
- Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Linda Popplewell
- Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
- National Horizons Centre, Teesside University, Darlington DL1 1HG, UK
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8
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Hakim CH, Burke MJ, Teixeira J, Duan D. Histological Assessment of Gene Therapy in the Canine DMD Model. Methods Mol Biol 2023; 2587:303-338. [PMID: 36401036 DOI: 10.1007/978-1-0716-2772-3_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Assessing histological changes is essential for characterizing muscle disease progression and for studying the response to therapies in Duchenne muscular dystrophy (DMD), an X-linked progressive muscle-wasting disease caused by the loss of the dystrophin protein. Canine models are by far the best-characterized large animal models for DMD. In this chapter, we describe methods for muscle tissue collection and storage, hematoxylin and eosin staining for studying general muscle morphology, and special staining protocols for evaluating fibrosis, calcification, and neuronal nitric oxide synthase (nNOS) activity. We also provide immunofluorescence staining protocols that are often used to characterize the expression and localization of dystrophin and components of the dystrophin-associated glycoprotein complex. Lastly, we presented immunohistochemical staining protocols that we use to assess muscle inflammation and immune responses.
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Affiliation(s)
- Chady H Hakim
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, MO, USA
| | - Matthhew J Burke
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, MO, USA
| | - James Teixeira
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, MO, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, MO, USA.
- Department of Biomedical, Biological & Chemical Engineering, College of Engineering, The University of Missouri, Columbia, MO, USA.
- Department of Neurology, School of Medicine, The University of Missouri, Columbia, MO, USA.
- Department of Biomedical Sciences, College of Veterinary Medicine, The University of Missouri, Columbia, MO, USA.
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Dubuisson N, Versele R, Planchon C, Selvais CM, Noel L, Abou-Samra M, Davis-López de Carrizosa MA. Histological Methods to Assess Skeletal Muscle Degeneration and Regeneration in Duchenne Muscular Dystrophy. Int J Mol Sci 2022; 23:16080. [PMID: 36555721 PMCID: PMC9786356 DOI: 10.3390/ijms232416080] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 12/09/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a progressive disease caused by the loss of function of the protein dystrophin. This protein contributes to the stabilisation of striated cells during contraction, as it anchors the cytoskeleton with components of the extracellular matrix through the dystrophin-associated protein complex (DAPC). Moreover, absence of the functional protein affects the expression and function of proteins within the DAPC, leading to molecular events responsible for myofibre damage, muscle weakening, disability and, eventually, premature death. Presently, there is no cure for DMD, but different treatments help manage some of the symptoms. Advances in genetic and exon-skipping therapies are the most promising intervention, the safety and efficiency of which are tested in animal models. In addition to in vivo functional tests, ex vivo molecular evaluation aids assess to what extent the therapy has contributed to the regenerative process. In this regard, the later advances in microscopy and image acquisition systems and the current expansion of antibodies for immunohistological evaluation together with the development of different spectrum fluorescent dyes have made histology a crucial tool. Nevertheless, the complexity of the molecular events that take place in dystrophic muscles, together with the rise of a multitude of markers for each of the phases of the process, makes the histological assessment a challenging task. Therefore, here, we summarise and explain the rationale behind different histological techniques used in the literature to assess degeneration and regeneration in the field of dystrophinopathies, focusing especially on those related to DMD.
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Affiliation(s)
- Nicolas Dubuisson
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research, Medical Sector, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 55, 1200 Brussels, Belgium
- Neuromuscular Reference Center, Cliniques Universitaires Saint-Luc (CUSL), Avenue Hippocrate 10, 1200 Brussels, Belgium
| | - Romain Versele
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research, Medical Sector, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 55, 1200 Brussels, Belgium
| | - Chloé Planchon
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research, Medical Sector, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 55, 1200 Brussels, Belgium
| | - Camille M. Selvais
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research, Medical Sector, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 55, 1200 Brussels, Belgium
| | - Laurence Noel
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research, Medical Sector, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 55, 1200 Brussels, Belgium
| | - Michel Abou-Samra
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research, Medical Sector, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 55, 1200 Brussels, Belgium
| | - María A. Davis-López de Carrizosa
- Endocrinology, Diabetes and Nutrition Unit, Institute of Experimental and Clinical Research, Medical Sector, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 55, 1200 Brussels, Belgium
- Departamento de Fisiología, Facultad de Biología, Universidad de Sevilla, 41012 Seville, Spain
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10
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CRISPR-Based Therapeutic Gene Editing for Duchenne Muscular Dystrophy: Advances, Challenges and Perspectives. Cells 2022; 11:cells11192964. [PMID: 36230926 PMCID: PMC9564082 DOI: 10.3390/cells11192964] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/06/2022] [Accepted: 09/09/2022] [Indexed: 11/19/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a severe neuromuscular disease arising from loss-of-function mutations in the dystrophin gene and characterized by progressive muscle degeneration, respiratory insufficiency, cardiac failure, and premature death by the age of thirty. Albeit DMD is one of the most common types of fatal genetic diseases, there is no curative treatment for this devastating disorder. In recent years, gene editing via the clustered regularly interspaced short palindromic repeats (CRISPR) system has paved a new path toward correcting pathological mutations at the genetic source, thus enabling the permanent restoration of dystrophin expression and function throughout the musculature. To date, the therapeutic benefits of CRISPR genome-editing systems have been successfully demonstrated in human cells, rodents, canines, and piglets with diverse DMD mutations. Nevertheless, there remain some nonignorable challenges to be solved before the clinical application of CRISPR-based gene therapy. Herein, we provide an overview of therapeutic CRISPR genome-editing systems, summarize recent advancements in their applications in DMD contexts, and discuss several potential obstacles lying ahead of clinical translation.
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11
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Abstract
Duchenne muscular dystrophy (DMD) is an X-linked, muscle wasting disease that affects 1 in 5000 males. Affected individuals become wheelchair bound by the age of twelve and eventually die in their third decade due to respiratory and cardiac complications. The disease is caused by mutations in the DMD gene that codes for dystrophin. Dystrophin is a structural protein that maintains the integrity of muscle fibres and protects them from contraction-induced damage. The absence of dystrophin compromises the stability and function of the muscle fibres, eventually leading to muscle degeneration. So far, there is no effective treatment for deteriorating muscle function in DMD patients. A promising approach for treating this life-threatening disease is gene transfer to restore dystrophin expression using a safe, non-pathogenic viral vector called adeno-associated viral (AAV) vector. Whilst microdystrophin gene transfer using AAV vectors shows extremely impressive therapeutic success so far in large animal models of DMD, translating this advanced therapy medicinal product from bench to bedside still offers scope for many optimization steps. In this paper, the authors review the current progress of AAV-microdystrophin gene therapy for DMD and other treatment strategies that may apply to a subset of DMD patients depending on the mutations they carry.
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Affiliation(s)
- Nertiyan Elangkovan
- Centres for Gene & Cell Therapy and Biomedical Sciences, Department of Biological Sciences, School of Life & Environmental Sciences, Royal Holloway - University of London, Surrey, TW20 0EX, UK
| | - George Dickson
- Centres for Gene & Cell Therapy and Biomedical Sciences, Department of Biological Sciences, School of Life & Environmental Sciences, Royal Holloway - University of London, Surrey, TW20 0EX, UK
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12
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Florczyk-Soluch U, Polak K, Dulak J. The multifaceted view of heart problem in Duchenne muscular dystrophy. Cell Mol Life Sci 2021; 78:5447-5468. [PMID: 34091693 PMCID: PMC8257522 DOI: 10.1007/s00018-021-03862-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 04/29/2021] [Accepted: 05/20/2021] [Indexed: 12/14/2022]
Abstract
Dystrophin is a large protein serving as local scaffolding repetitively bridging cytoskeleton and the outside of striated muscle cell. As such dystrophin is a critical brick primarily in dystrophin-associated protein complex (DAGC) and in a larger submembranous unit, costamere. Accordingly, the lack of functional dystrophin laying at the root of Duchenne muscular dystrophy (DMD) drives sarcolemma instability. From this point on, the cascade inevitably leading to the death of myocyte begins. In cardiomyocytes, intracellular calcium overload and related mitochondrial-mediated cell death mainly contribute to myocardial dysfunction and dilation while other protein dysregulation and/or mislocalization may affect electrical conduction system and favor arrhythmogenesis. Although clinically DMD manifests as progressive muscle weakness and skeletal muscle symptoms define characteristic of DMD, it is the heart problem the biggest challenge that most often develop in the form of dilated cardiomyopathy (DCM). Current standards of treatment and recent progress in respiratory care, introduced in most settings in the 1990s, have improved quality of life and median life expectancy to 4th decade of patient's age. At the same time, cardiac causes of death related to DMD increases. Despite preventive and palliative cardiac treatments available, the prognoses remain poor. Direct therapeutic targeting of dystrophin deficiency is critical, however, hindered by the large size of the dystrophin cDNA and/or stochastic, often extensive genetic changes in DMD gene. The correlation between cardiac involvement and mutations affecting specific dystrophin isoforms, may provide a mutation-specific cardiac management and novel therapeutic approaches for patients with CM. Nonetheless, the successful cardiac treatment poses a big challenge and may require combined therapy to combat dystrophin deficiency and its after-effects (critical in DMD pathogenesis). This review locates the multifaceted heart problem in the course of DMD, balancing the insights into basic science, translational efforts and clinical manifestation of dystrophic heart disease.
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Affiliation(s)
- Urszula Florczyk-Soluch
- Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland.
| | - Katarzyna Polak
- Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Józef Dulak
- Department of Medical Biotechnology, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
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13
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Kodippili K, Thorne PK, Laughlin MH, Duan D. Dystrophin deficiency impairs vascular structure and function in the canine model of Duchenne muscular dystrophy. J Pathol 2021; 254:589-605. [PMID: 33999411 DOI: 10.1002/path.5704] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 04/02/2021] [Accepted: 05/12/2021] [Indexed: 01/03/2023]
Abstract
Duchenne muscular dystrophy (DMD) is a muscle-wasting disease caused by dystrophin deficiency. Vascular dysfunction has been suggested as an underlying pathogenic mechanism in DMD. However, this has not been thoroughly studied in a large animal model. Here we investigated structural and functional changes in the vascular smooth muscle and endothelium of the canine DMD model. The expression of dystrophin and endothelial nitric oxide synthase (eNOS), neuronal NOS (nNOS), and the structure and function of the femoral artery from 15 normal and 16 affected adult dogs were evaluated. Full-length dystrophin was detected in the endothelium and smooth muscle in normal but not affected dog arteries. Normal arteries lacked nNOS but expressed eNOS in the endothelium. NOS activity and eNOS expression were reduced in the endothelium of dystrophic dogs. Dystrophin deficiency resulted in structural remodeling of the artery. In affected dogs, the maximum tension induced by vasoconstrictor phenylephrine and endothelin-1 was significantly reduced. In addition, acetylcholine-mediated vasorelaxation was significantly impaired, whereas exogenous nitric oxide-induced vasorelaxation was significantly enhanced. Our results suggest that dystrophin plays a crucial role in maintaining the structure and function of vascular endothelium and smooth muscle in large mammals. Vascular defects may contribute to DMD pathogenesis. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Affiliation(s)
- Kasun Kodippili
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA
| | - Pamela K Thorne
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - M Harold Laughlin
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA.,Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA.,Department of Neurology, School of Medicine, University of Missouri, Columbia, MO, USA.,Department of Biomedical, Biological & Chemical Engineering, College of Engineering, University of Missouri, Columbia, MO, USA
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14
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Abstract
Duchenne muscular dystrophy is a severe, progressive, muscle-wasting disease that leads to difficulties with movement and, eventually, to the need for assisted ventilation and premature death. The disease is caused by mutations in DMD (encoding dystrophin) that abolish the production of dystrophin in muscle. Muscles without dystrophin are more sensitive to damage, resulting in progressive loss of muscle tissue and function, in addition to cardiomyopathy. Recent studies have greatly deepened our understanding of the primary and secondary pathogenetic mechanisms. Guidelines for the multidisciplinary care for Duchenne muscular dystrophy that address obtaining a genetic diagnosis and managing the various aspects of the disease have been established. In addition, a number of therapies that aim to restore the missing dystrophin protein or address secondary pathology have received regulatory approval and many others are in clinical development.
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Affiliation(s)
- Dongsheng Duan
- Department of Molecular Microbiology and Immunology and Department of Neurology, School of Medicine; Department of Biomedical Sciences, College of Veterinary Medicine; Department of Biomedical, Biological & Chemical Engineering, College of Engineering, University of Missouri, Columbia, MO, USA
| | - Nathalie Goemans
- Department of Child Neurology, University Hospitals Leuven, Leuven, Belgium
| | | | - Eugenio Mercuri
- Centro Clinico Nemo, Policlinico Gemelli, Rome, Italy
- Peadiatric Neurology, Catholic University, Rome, Italy
| | - Annemieke Aartsma-Rus
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands.
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15
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Potter RA, Griffin DA, Heller KN, Peterson EL, Clark EK, Mendell JR, Rodino-Klapac LR. Dose-Escalation Study of Systemically Delivered rAAVrh74.MHCK7.micro-dystrophin in the mdx Mouse Model of Duchenne Muscular Dystrophy. Hum Gene Ther 2021; 32:375-389. [PMID: 33397205 PMCID: PMC8063270 DOI: 10.1089/hum.2019.255] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a rare, X-linked, fatal, degenerative neuromuscular disease caused by mutations in the DMD gene. More than 2,000 mutations of the DMD gene are responsible for progressive loss of muscle strength, loss of ambulation, and generally respiratory and cardiac failure by age 30. Recently, gene transfer therapy has received widespread interest as a disease-modifying treatment for all patients with DMD. We designed an adeno-associated virus vector (rAAVrh74) containing a codon-optimized human micro-dystrophin transgene driven by a skeletal and cardiac muscle-specific promoter, MHCK7. To test the efficacy of rAAVrh74.MHCK7.micro-dystrophin, we evaluated systemic injections in mdx (dystrophin-null) mice at low (2 × 1012 vector genome [vg] total dose, 8 × 1013 vg/kg), intermediate (6 × 1012 vg total dose, 2 × 1014 vg/kg), and high doses (1.2 × 1013 vg total dose, 6 × 1014 vg/kg). Three months posttreatment, specific force increased in the diaphragm (DIA) and tibialis anterior muscle, with intermediate and high doses eliciting force outputs at wild-type (WT) levels. Histological improvement included reductions in fibrosis and normalization of myofiber size, specifically in the DIA, where results for low and intermediate doses were not significantly different from the WT. Significant reduction in central nucleation was also observed, although complete normalization to WT was not seen. No vector-associated toxicity was reported either by clinical or organ-specific laboratory assessments or following formal histopathology. The findings in this preclinical study provided proof of principle for safety and efficacy of systemic delivery of rAAVrh74.MHCK7.micro-dystrophin at high vector titers, supporting initiation of a Phase I/II safety study in boys with DMD.
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Affiliation(s)
- Rachael A Potter
- Sarepta Therapeutics, Inc., Cambridge, Massachusetts, USA.,Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Danielle A Griffin
- Sarepta Therapeutics, Inc., Cambridge, Massachusetts, USA.,Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Kristin N Heller
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Ellyn L Peterson
- Sarepta Therapeutics, Inc., Cambridge, Massachusetts, USA.,Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Emma K Clark
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Jerry R Mendell
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,Department of Pediatrics and Neurology, The Ohio State University, Columbus, Ohio, USA
| | - Louise R Rodino-Klapac
- Sarepta Therapeutics, Inc., Cambridge, Massachusetts, USA.,Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,Department of Pediatrics and Neurology, The Ohio State University, Columbus, Ohio, USA
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16
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Nakada S, Yamashita Y, Machida S, Miyagoe-Suzuki Y, Arikawa-Hirasawa E. Perlecan Facilitates Neuronal Nitric Oxide Synthase Delocalization in Denervation-Induced Muscle Atrophy. Cells 2020; 9:cells9112524. [PMID: 33238404 PMCID: PMC7700382 DOI: 10.3390/cells9112524] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 11/17/2020] [Accepted: 11/19/2020] [Indexed: 01/01/2023] Open
Abstract
Perlecan is an extracellular matrix molecule anchored to the sarcolemma by a dystrophin–glycoprotein complex. Perlecan-deficient mice are tolerant to muscle atrophy, suggesting that perlecan negatively regulates mechanical stress-dependent skeletal muscle mass. Delocalization of neuronal nitric oxide synthase (nNOS) from the sarcolemma to the cytosol triggers protein degradation, thereby initiating skeletal muscle atrophy. We hypothesized that perlecan regulates nNOS delocalization and activates protein degradation during this process. To determine the role of perlecan in nNOS-mediated mechanotransduction, we used sciatic nerve transection as a denervation model of gastrocnemius muscles. Gastrocnemius muscle atrophy was significantly lower in perinatal lethality-rescued perlecan-knockout (Hspg2−/−-Tg) mice than controls (WT-Tg) on days 4 and 14 following surgery. Immunofluorescence microscopy showed that cell membrane nNOS expression was reduced by denervation in WT-Tg mice, with marginal effects in Hspg2−/−-Tg mice. Moreover, levels of atrophy-related proteins—i.e., FoxO1a, FoxO3a, atrogin-1, and Lys48-polyubiquitinated proteins—increased in the denervated muscles of WT-Tg mice but not in Hspg2−/−-Tg mice. These findings suggest that during denervation, perlecan promotes nNOS delocalization from the membrane and stimulates protein degradation and muscle atrophy by activating FoxO signaling and the ubiquitin–proteasome system.
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Affiliation(s)
- Satoshi Nakada
- Japanese Center for Research on Women in Sport, Juntendo University Graduate School of Health and Sports Science, Chiba 270-1695, Japan; (S.N.); (S.M.)
| | - Yuri Yamashita
- Research Institute for Diseases of Old Age, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan;
| | - Shuichi Machida
- Japanese Center for Research on Women in Sport, Juntendo University Graduate School of Health and Sports Science, Chiba 270-1695, Japan; (S.N.); (S.M.)
| | - Yuko Miyagoe-Suzuki
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo 187-8502, Japan;
| | - Eri Arikawa-Hirasawa
- Japanese Center for Research on Women in Sport, Juntendo University Graduate School of Health and Sports Science, Chiba 270-1695, Japan; (S.N.); (S.M.)
- Research Institute for Diseases of Old Age, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan;
- Correspondence: ; Tel.: +81-3-3813-3111
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17
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Péladeau C, Jasmin BJ. Targeting IRES-dependent translation as a novel approach for treating Duchenne muscular dystrophy. RNA Biol 2020; 18:1238-1251. [PMID: 33164678 DOI: 10.1080/15476286.2020.1847894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Internal-ribosomal entry sites (IRES) are translational elements that allow the initiation machinery to start protein synthesis via internal initiation. IRESs promote tissue-specific translation in stress conditions when conventional cap-dependent translation is inhibited. Since many IRES-containing mRNAs are relevant to diseases, this cellular mechanism is emerging as an attractive therapeutic target for pharmacological and genetic modulations. Indeed, there has been growing interest over the past years in determining the therapeutic potential of IRESs for several disease conditions such as cancer, neurodegeneration and neuromuscular diseases including Duchenne muscular dystrophy (DMD). IRESs relevant for DMD have been identified in several transcripts whose protein product results in functional improvements in dystrophic muscles. Together, these converging lines of evidence indicate that activation of IRES-mediated translation of relevant transcripts in DMD muscle represents a novel and appropriate therapeutic strategy for DMD that warrants further investigation, particularly to identify agents that can modulate their activity.
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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, Ontario, 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, Ontario, Canada
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18
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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] [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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19
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Zhao J, Yue Y, Patel A, Wasala L, Karp JF, Zhang K, Duan D, Lai Y. High-Resolution Histological Landscape of AAV DNA Distribution in Cellular Compartments and Tissues following Local and Systemic Injection. Mol Ther Methods Clin Dev 2020; 18:856-868. [PMID: 32953935 PMCID: PMC7479330 DOI: 10.1016/j.omtm.2020.08.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 08/06/2020] [Indexed: 12/21/2022]
Abstract
Adeno-associated virus (AAV) is one of the most important gene delivery vehicles for in vivo gene therapy. Intramuscular (i.m.) and intravascular (i.v.) injection are commonly used for AAV gene transfer. Unfortunately, the fate of AAV vectors following administration remains unclear at the histological level. Taking advantage of RNAscope, a recently developed in situ hybridization technique that can reveal high-resolution viral DNA localization information, in this study, we evaluated body-wide distribution of an AAV9 vector in the context of the cell and tissue microenvironments. We observed distinctive kinetics of cell and nuclear entry of the AAV DNA in striated muscle and liver following i.m. and i.v. injection. We also found characteristic distribution patterns of the AAV DNA in various histological structures in internal organs, including gonads and lymph nodes, following i.v. injection. Finally, we showed significantly body-wide spreading of the AAV DNA following i.m. injection. These results add a new dimension to our understanding of AAV transduction biology and provide a basis for assessing the full impact of AAV gene therapy.
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Affiliation(s)
- Junling Zhao
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Yongping Yue
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Aman Patel
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
- School of Medicine, Saint Louis University, St. Louis, MO 63104, USA
| | - Lakmini Wasala
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Jacob F. Karp
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Keqing Zhang
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO 65212, USA
- Department of Neurology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
- Department of Bioengineering, University of Missouri, Columbia, MO 65212, USA
| | - Yi Lai
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
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20
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Rodgers BD, Bishaw Y, Kagel D, Ramos JN, Maricelli JW. Micro-dystrophin Gene Therapy Partially Enhances Exercise Capacity in Older Adult mdx Mice. Mol Ther Methods Clin Dev 2020; 17:122-132. [PMID: 31909085 PMCID: PMC6939027 DOI: 10.1016/j.omtm.2019.11.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 11/20/2019] [Indexed: 01/09/2023]
Abstract
Micro-dystrophin (μDys) gene therapeutics can improve striated muscle structure and function in different animal models of Duchenne muscular dystrophy. Most studies, however, used young mdx mice that lack a pronounced dystrophic phenotype, short treatment periods, and limited muscle function tests. We, therefore, determined the relative efficacy of two previously described μDys gene therapeutics (rAAV6:μDysH3 and rAAV6:μDys5) in 6-month-old mdx mice using a 6-month treatment regimen and forced exercise. Forelimb and hindlimb grip strength, metabolic rate (VO2 max), running efficiency (energy expenditure), and serum creatine kinase levels similarly improved in mdx mice treated with either vector. Both vectors produced nearly identical dose-responses in all assays. They also partially prevented the degenerative effects of repeated high-intensity exercise on muscle histology, although none of the metrics examined was restored to normal wild-type levels. Moreover, neither vector had any consistent effect on respiration while exercising. These data together suggest that, although μDys gene therapy can improve isolated and systemic muscle function, it may be only partially effective when dystrophinopathies are advanced or when muscle structure is significantly challenged, as with high-intensity exercise. This further suggests that restoring muscle function to near-normal levels will likely require ancillary or combinatorial treatments capable of enhancing muscle strength.
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Affiliation(s)
- Buel D. Rodgers
- School of Molecular Biosciences, Washington Center for Muscle Biology, Washington State University, Pullman, WA 99164, USA
| | - Yemeserach Bishaw
- School of Molecular Biosciences, Washington Center for Muscle Biology, Washington State University, Pullman, WA 99164, USA
| | - Denali Kagel
- School of Molecular Biosciences, Washington Center for Muscle Biology, Washington State University, Pullman, WA 99164, USA
| | - Julian N. Ramos
- Department of Neurology, Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Washington, Seattle, WA 98195, USA
- Molecular and Cellular Biology Program, University of Washington School of Medicine, Seattle, WA, USA
| | - Joseph W. Maricelli
- School of Molecular Biosciences, Washington Center for Muscle Biology, Washington State University, Pullman, WA 99164, USA
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21
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Meng J, Sweeney NP, Doreste B, Muntoni F, McClure M, Morgan J. Restoration of Functional Full-Length Dystrophin After Intramuscular Transplantation of Foamy Virus-Transduced Myoblasts. Hum Gene Ther 2020; 31:241-252. [PMID: 31801386 PMCID: PMC7047098 DOI: 10.1089/hum.2019.224] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 11/24/2019] [Indexed: 12/12/2022] Open
Abstract
Stem cell therapy is a promising strategy to treat muscle diseases such as Duchenne muscular dystrophy (DMD). To avoid immune rejection of donor cells or donor-derived muscle, autologous cells, which have been genetically modified to express dystrophin, are preferable to cells derived from healthy donors. Restoration of full-length dystrophin (FL-dys) using viral vectors is extremely challenging, due to the limited packaging capacity of the vectors, but we have recently shown that either a foamy viral or lentiviral vector is able to package FL-dys open-reading frame and transduce myoblasts derived from a DMD patient. Differentiated myotubes derived from these transduced cells produced FL-dys. Here, we transplanted the foamy viral dystrophin-corrected DMD myoblasts intramuscularly into mdx nude mice, and showed that the transduced cells contributed to muscle regeneration, expressing FL-dys in nearly all the muscle fibers of donor origin. Furthermore, we showed that the restored FL-dys recruited members of the dystrophin-associated protein complex and neuronal nitric oxide synthase within donor-derived muscle fibers, evidence that the restored dystrophin protein is functional. Dystrophin-expressing donor-derived muscle fibers expressed lower levels of utrophin than host muscle fibers, providing additional evidence of functional improvement of donor-derived myofibers. This is the first in vivo evidence that foamy virus vector-transduced DMD myoblasts can contribute to muscle regeneration and mediate functional dystrophin restoration following their intramuscular transplantation, representing a promising therapeutic strategy for individual small muscles in DMD.
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Affiliation(s)
- Jinhong Meng
- Developmental Neuroscience Programme, Molecular Neurosciences Section, Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
- National Institute for Health Research, Great Ormond Street Institute of Child Health Biomedical Research Centre, University College London, London, United Kingdom
| | - Nathan Paul Sweeney
- Jefferiss Research Trust Laboratories, Imperial College London, London, United Kingdom
| | - Bruno Doreste
- Developmental Neuroscience Programme, Molecular Neurosciences Section, Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
- National Institute for Health Research, Great Ormond Street Institute of Child Health Biomedical Research Centre, University College London, London, United Kingdom
| | - Francesco Muntoni
- Developmental Neuroscience Programme, Molecular Neurosciences Section, Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
- National Institute for Health Research, Great Ormond Street Institute of Child Health Biomedical Research Centre, University College London, London, United Kingdom
| | - Myra McClure
- Jefferiss Research Trust Laboratories, Imperial College London, London, United Kingdom
| | - Jennifer Morgan
- Developmental Neuroscience Programme, Molecular Neurosciences Section, Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
- National Institute for Health Research, Great Ormond Street Institute of Child Health Biomedical Research Centre, University College London, London, United Kingdom
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22
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Zhao J, Yang HT, Wasala L, Zhang K, Yue Y, Duan D, Lai Y. Dystrophin R16/17 protein therapy restores sarcolemmal nNOS in trans and improves muscle perfusion and function. Mol Med 2019; 25:31. [PMID: 31266455 PMCID: PMC6607532 DOI: 10.1186/s10020-019-0101-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 06/20/2019] [Indexed: 01/08/2023] Open
Abstract
Background Delocalization of neuronal nitric oxide synthase (nNOS) from the sarcolemma leads to functional muscle ischemia. This contributes to the pathogenesis in cachexia, aging and muscular dystrophy. Mutations in the gene encoding dystrophin result in Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). In many BMD patients and DMD patients that have been converted to BMD by gene therapy, sarcolemmal nNOS is missing due to the lack of dystrophin nNOS-binding domain. Methods Dystrophin spectrin-like repeats 16 and 17 (R16/17) is the sarcolemmal nNOS localization domain. Here we explored whether R16/17 protein therapy can restore nNOS to the sarcolemma and prevent functional ischemia in transgenic mice which expressed an R16/17-deleted human micro-dystrophin gene in the dystrophic muscle. The palmitoylated R16/17.GFP fusion protein was conjugated to various cell-penetrating peptides and produced in the baculovirus-insect cell system. The best fusion protein was delivered to the transgenic mice and functional muscle ischemia was quantified. Results Among five candidate cell-penetrating peptides, the mutant HIV trans-acting activator of transcription (TAT) protein transduction domain (mTAT) was the best in transferring the R16/17.GFP protein to the muscle. Systemic delivery of the mTAT.R16/17.GFP protein to micro-dystrophin transgenic mice successfully restored sarcolemmal nNOS without inducing T cell infiltration. More importantly, R16/17 protein therapy effectively prevented treadmill challenge-induced force loss and improved muscle perfusion during contraction. Conclusions Our results suggest that R16/17 protein delivery is a highly promising therapy for muscle diseases involving sarcolemmal nNOS delocalizaton. Electronic supplementary material The online version of this article (10.1186/s10020-019-0101-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Junling Zhao
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA
| | - Hsiao Tung Yang
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, 65212, USA
| | - Lakmini Wasala
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA
| | - Keqing Zhang
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA
| | - Yongping Yue
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA. .,Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, 65212, USA. .,Department of Neurology, School of Medicine, University of Missouri, Columbia, MO, 65212, USA. .,Department of Bioengineering, University of Missouri, Columbia, MO, 65212, USA.
| | - Yi Lai
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA.
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23
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Adams ME, Odom GL, Kim MJ, Chamberlain JS, Froehner SC. Syntrophin binds directly to multiple spectrin-like repeats in dystrophin and mediates binding of nNOS to repeats 16-17. Hum Mol Genet 2019; 27:2978-2985. [PMID: 29790927 DOI: 10.1093/hmg/ddy197] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/14/2018] [Indexed: 11/12/2022] Open
Abstract
Mutation of the gene encoding dystrophin leads to Duchenne and Becker muscular dystrophy (DMD and BMD). Currently, dystrophin is thought to function primarily as a structural protein, connecting the muscle cell actin cytoskeleton to the extra-cellular matrix. In addition to this structural role, dystrophin also plays an important role as a scaffold that organizes an array of signaling proteins including sodium, potassium, and calcium channels, kinases, and nitric oxide synthase (nNOS). Many of these signaling proteins are linked to dystrophin via syntrophin, an adapter protein that is known to bind directly to two sites in the carboxyl terminal region of dystrophin. A search of the dystrophin sequence revealed three additional potential syntrophin binding sites (SBSs) within the spectrin-like repeat (SLR) region of dystrophin. Binding assays revealed that the site at SLR 17 bound specifically to the α isoform of syntrophin while the site at SLR 22 bound specifically to the β-syntrophins. The SLR 17 α-SBS contained the core sequence known to be required for nNOS-dystrophin interaction. In vitro and in vivo assays indicate that α-syntrophin facilitates the nNOS-dystrophin interaction at this site rather than nNOS binding directly to dystrophin as previously reported. The identification of multiple SBSs within the SLR region of dystrophin demonstrates that this region functions as a signaling scaffold. The signaling role of the SLR region of dystrophin will need to be considered for effective gene replacement or exon skipping based DMD/BMD therapies.
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Affiliation(s)
- Marvin E Adams
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7290, USA
| | - Guy L Odom
- Department of Neurology, University of Washington, Seattle, WA 98195-7290, USA.,Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center, University of Washington, Seattle, WA 98195-7720, USA
| | - Min Jeong Kim
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7290, USA
| | - Jeffrey S Chamberlain
- Department of Neurology, University of Washington, Seattle, WA 98195-7290, USA.,Department of Biochemistry, University of Washington, Seattle, WA 98195-7290, USA.,Senator Paul D. Wellstone Muscular Dystrophy Cooperative Research Center, University of Washington, Seattle, WA 98195-7720, USA
| | - Stanley C Froehner
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7290, USA
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24
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Balke JE, Zhang L, Percival JM. Neuronal nitric oxide synthase (nNOS) splice variant function: Insights into nitric oxide signaling from skeletal muscle. Nitric Oxide 2018; 82:35-47. [PMID: 30503614 DOI: 10.1016/j.niox.2018.11.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 11/19/2018] [Accepted: 11/20/2018] [Indexed: 02/07/2023]
Abstract
Defects in neuronal nitric oxide synthase (nNOS) splice variant localization and signaling in skeletal muscle are a firmly established pathogenic characteristic of many neuromuscular diseases, including Duchenne and Becker muscular dystrophy (DMD and BMD, respectively). Therefore, substantial efforts have been made to understand and therapeutically target skeletal muscle nNOS isoform signaling. The purpose of this review is to summarize recent salient advances in understanding of the regulation, targeting, and function of nNOSμ and nNOSβ splice variants in normal and dystrophic skeletal muscle, primarily using findings from mouse models. The first focus of this review is how the differential targeting of nNOS splice variants creates spatially and functionally distinct nitric oxide (NO) signaling compartments at the sarcolemma, Golgi complex, and cytoplasm. Particular attention is given to the functions of sarcolemmal nNOSμ and limitations of current nNOS knockout models. The second major focus is to review current understanding of cGMP-mediated nNOS signaling in skeletal muscle and its emergence as a therapeutic target in DMD and BMD. Accordingly, we address the preclinical and clinical successes and setbacks with the testing of phosphodiesterase 5 inhibitors to redress nNOS signaling defects in DMD and BMD. In summary, this review of nNOS function in normal and dystrophic muscle aims to advance understanding how the messenger NO is harnessed for cellular signaling from a skeletal muscle perspective.
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Affiliation(s)
- Jordan E Balke
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine Miami, Florida, 33101, USA
| | - Ling Zhang
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine Miami, Florida, 33101, USA
| | - Justin M Percival
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine Miami, Florida, 33101, USA.
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25
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Patel A, Zhao J, Yue Y, Zhang K, Duan D, Lai Y. Dystrophin R16/17-syntrophin PDZ fusion protein restores sarcolemmal nNOSμ. Skelet Muscle 2018; 8:36. [PMID: 30466494 PMCID: PMC6251231 DOI: 10.1186/s13395-018-0182-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 11/07/2018] [Indexed: 12/18/2022] Open
Abstract
Background Loss of sarcolemmal nNOSμ is a common manifestation in a wide variety of muscle diseases and contributes to the dysregulation of multiple muscle activities. Given the critical role sarcolemmal nNOSμ plays in muscle, restoration of sarcolemmal nNOSμ should be considered as an important therapeutic goal. Methods nNOSμ is anchored to the sarcolemma by dystrophin spectrin-like repeats 16 and 17 (R16/17) and the syntrophin PDZ domain (Syn PDZ). To develop a strategy that can independently restore sarcolemmal nNOSμ, we engineered an R16/17-Syn PDZ fusion construct and tested whether this construct alone is sufficient to anchor nNOSμ to the sarcolemma in three different mouse models of Duchenne muscular dystrophy (DMD). Results Membrane-associated nNOSμ is completely lost in DMD. Adeno-associated virus (AAV)-mediated delivery of the R16/17-Syn PDZ fusion construct successfully restored sarcolemmal nNOSμ in all three models. Further, nNOS restoration was independent of the dystrophin-associated protein complex. Conclusions Our results suggest that the R16/17-Syn PDZ fusion construct is sufficient to restore sarcolemmal nNOSμ in the dystrophin-null muscle. Electronic supplementary material The online version of this article (10.1186/s13395-018-0182-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Aman Patel
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA
| | - Junling Zhao
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA
| | - Yongping Yue
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA
| | - Keqing Zhang
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA. .,Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, 65212, USA. .,Department of Neurology, School of Medicine, University of Missouri, Columbia, MO, 65212, USA. .,Department of Bioengineering, University of Missouri, Columbia, MO, 65212, USA.
| | - Yi Lai
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Medical Sciences Building, One Hospital Drive, Columbia, MO, 65212, USA.
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26
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Percival JM. Perspective: Spectrin-Like Repeats in Dystrophin Have Unique Binding Preferences for Syntrophin Adaptors That Explain the Mystery of How nNOSμ Localizes to the Sarcolemma. Front Physiol 2018; 9:1369. [PMID: 30349485 PMCID: PMC6186803 DOI: 10.3389/fphys.2018.01369] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 09/10/2018] [Indexed: 11/13/2022] Open
Abstract
Dystrophin is a massive multi-domain protein composed of specialized amino and carboxyl termini that are separated by 24 spectrin-like repeats. Dystrophin performs critical structural and signaling roles that are indispensable for the functional integrity of skeletal muscle. Indeed, the loss of dystrophin protein expression causes the muscle wasting disease, Duchenne muscular dystrophy (DMD). Substantial progress has been made in defining the functions of the domains of dystrophin, which has proven invaluable for the development of miniaturized dystrophin gene and exon skipping therapies for DMD. However, a long-standing mystery regarding dystrophin function is how dystrophin, and its adaptor and neuronal nitric oxide synthase mu (nNOSμ) binding partner α-syntrophin, cooperate to localize nNOSμ to the sarcolemma. Only when localized to the sarcolemma can nNOSμ override sympathetic vasoconstriction and prevent functional ischemia in contracting muscles. Current evidence suggests that spectrin-like repeat 17 of dystrophin and α-syntrophin cooperate to localize nNOSμ to the sarcolemma. However, the exact mechanism remains unclear and controversial because of equivocal evidence for direct binding of dystrophin and nNOSμ. Recently, an important study identified a novel α-syntrophin binding site within spectrin-like repeat 17, leading to a new model whereby α-syntrophin recruits nNOSμ to the sarcolemmal dystrophin complex by binding spectrin-like repeat 17. This model finally appears to solve the mystery of the dual requirement for dystrophin and α-syntrophin for sarcolemmal nNOSμ localization. The aim of the current perspective is to highlight this major advance in understanding of dystrophin’s role in localizing nNOSμ and its implications for current trials.
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Affiliation(s)
- Justin M Percival
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, United States
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27
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Kodippili K, Hakim CH, Yang HT, Pan X, Yang NN, Laughlin MH, Terjung RL, Duan D. Nitric oxide-dependent attenuation of noradrenaline-induced vasoconstriction is impaired in the canine model of Duchenne muscular dystrophy. J Physiol 2018; 596:5199-5216. [PMID: 30152022 DOI: 10.1113/jp275672] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 08/08/2018] [Indexed: 12/31/2022] Open
Abstract
KEY POINTS We developed a novel method to study sympatholysis in dogs. We showed abolishment of sarcolemmal nNOS, and reduction of total nNOS and total eNOS in the canine Duchenne muscular dystrophy (DMD) model. We showed sympatholysis in dogs involving both nNOS-derived NO-dependent and NO-independent mechanisms. We showed that the loss of sarcolemmal nNOS compromised sympatholysis in the canine DMD model. We showed that NO-independent sympatholysis was not affected in the canine DMD model. ABSTRACT The absence of dystrophin in Duchenne muscular dystrophy (DMD) leads to the delocalization of neuronal nitric oxide synthase (nNOS) from the sarcolemma. Sarcolemmal nNOS plays an important role in sympatholysis, a process of attenuating reflex sympathetic vasoconstriction during exercise to ensure blood perfusion in working muscle. Delocalization of nNOS compromises sympatholysis resulting in functional ischaemia and muscle damage in DMD patients and mouse models. Little is known about the contribution of membrane-associated nNOS to blood flow regulation in dystrophin-deficient DMD dogs. We tested the hypothesis that the loss of sarcolemmal nNOS abolishes protective sympatholysis in contracting muscle of affected dogs. Haemodynamic responses to noradrenaline in the brachial artery were evaluated at rest and during contraction in the absence and presence of NOS inhibitors. We found sympatholysis was significantly compromised in DMD dogs, as well as in normal dogs treated with a selective nNOS inhibitor, suggesting that the absence of sarcolemmal nNOS underlies defective sympatholysis in the canine DMD model. Surprisingly, inhibition of all NOS isoforms did not completely abolish sympatholysis in normal dogs, suggesting sympatholysis in canine muscle also involves NO-independent mechanism(s). Our study established a foundation for using the dog model to test therapies aimed at restoring nNOS homeostasis in DMD.
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Affiliation(s)
- Kasun Kodippili
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA
| | - Chady H Hakim
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA.,National Center for Advancing Translational Sciences (NCATS), Bethesda, MD, USA
| | - Hsiao T Yang
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA.,Department of Veterinary Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Xiufang Pan
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA
| | - N Nora Yang
- National Center for Advancing Translational Sciences (NCATS), Bethesda, MD, USA
| | - Maurice H Laughlin
- Department of Veterinary Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Ronald L Terjung
- Department of Veterinary Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, University of Missouri, Columbia, MO, USA.,Department of Veterinary Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA.,Department of Neurology, School of Medicine, University of Missouri, Columbia, MO, USA.,Department of Bioengineering, University of Missouri, Columbia, MO, USA
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28
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Tremblay JP, Iyombe-Engembe JP, Duchêne B, Ouellet DL. Gene Editing for Duchenne Muscular Dystrophy Using the CRISPR/Cas9 Technology: The Importance of Fine-tuning the Approach. Mol Ther 2018; 24:1888-1889. [PMID: 27916992 DOI: 10.1038/mt.2016.191] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Affiliation(s)
- Jacques P Tremblay
- Centre de Recherche du CHU de Québec-Université Laval, Quebec, Quebec, Canada.
| | | | - Benjamin Duchêne
- Centre de Recherche du CHU de Québec-Université Laval, Quebec, Quebec, Canada
| | - Dominique L Ouellet
- Centre de Recherche du CHU de Québec-Université Laval, Quebec, Quebec, Canada
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29
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Dombernowsky NW, Ölmestig JNE, Witting N, Kruuse C. Role of neuronal nitric oxide synthase (nNOS) in Duchenne and Becker muscular dystrophies - Still a possible treatment modality? Neuromuscul Disord 2018; 28:914-926. [PMID: 30352768 DOI: 10.1016/j.nmd.2018.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 08/07/2018] [Accepted: 09/05/2018] [Indexed: 02/08/2023]
Abstract
Neuronal nitric oxide synthase (nNOS) is involved in nitric oxide (NO) production and suggested to play a crucial role in blood flow regulation of skeletal muscle. During activation of the muscle, NO helps attenuate the sympathetic vasoconstriction to accommodate increased metabolic demands, a phenomenon known as functional sympatholysis. In inherited myopathies such as the dystrophinopathies Duchenne and Becker muscle dystrophies (DMD and BMD), nNOS is lost from the sarcolemma. The loss of nNOS may cause functional ischemia contributing to skeletal and cardiac muscle cell injury. Effects of NO is augmented by inhibiting degradation of the second messenger cyclic guanosine monophosphate (cGMP) using sildenafil and tadalafil, both of which inhibit the enzyme phosphodiesterase 5 (PDE5). In animal models of DMD, PDE5-inhibitors prevent functional ischemia, reduce post-exercise skeletal muscle pathology and fatigue, show amelioration of cardiac muscle cell damage and increase cardiac performance. However, effect on clinical outcomes in DMD and BMD patients have been disappointing with minor effects on upper limb performance and none on ambulation. This review aims to summarize the current knowledge of nNOS function related to functional sympatholysis in skeletal muscle and studies on PDE5-inhibitor treatment in nNOS-deficient animal models and patients.
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Affiliation(s)
- Nanna W Dombernowsky
- Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Denmark
| | - Joakim N E Ölmestig
- Department of Neurology, Neurovascular Research Unit, Herlev Gentofte Hospital, University of Copenhagen, Denmark
| | - Nanna Witting
- Department of Neurology, Rigshospitalet Glostrup, University of Copenhagen, Denmark
| | - Christina Kruuse
- Department of Neurology, Neurovascular Research Unit, Herlev Gentofte Hospital, University of Copenhagen, Denmark; PDE Research Group, Lundbeck Foundation Center for Neurovascular Research (LUCENS), Denmark.
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30
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Duan D. Systemic AAV Micro-dystrophin Gene Therapy for Duchenne Muscular Dystrophy. Mol Ther 2018; 26:2337-2356. [PMID: 30093306 PMCID: PMC6171037 DOI: 10.1016/j.ymthe.2018.07.011] [Citation(s) in RCA: 280] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 07/05/2018] [Accepted: 07/11/2018] [Indexed: 12/23/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a lethal muscle disease caused by dystrophin gene mutation. Conceptually, replacing the mutated gene with a normal one would cure the disease. However, this task has encountered significant challenges due to the enormous size of the gene and the distribution of muscle throughout the body. The former creates a hurdle for viral vector packaging and the latter begs for whole-body therapy. To address these obstacles, investigators have invented the highly abbreviated micro-dystrophin gene and developed body-wide systemic gene transfer with adeno-associated virus (AAV). Numerous microgene configurations and various AAV serotypes have been explored in animal models in many laboratories. Preclinical data suggests that intravascular AAV micro-dystrophin delivery can significantly ameliorate muscle pathology, enhance muscle force, and attenuate dystrophic cardiomyopathy in animals. Against this backdrop, several clinical trials have been initiated to test the safety and tolerability of this promising therapy in DMD patients. While these trials are not powered to reach a conclusion on clinical efficacy, findings will inform the field on the prospects of body-wide DMD therapy with a synthetic micro-dystrophin AAV vector. This review discusses the history, current status, and future directions of systemic AAV micro-dystrophin therapy.
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Affiliation(s)
- Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA; Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA; Department of Neurology, School of Medicine, University of Missouri, Columbia, MO 65212, USA; Department of Bioengineering, University of Missouri, Columbia, MO 65212, USA.
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31
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Relation of nNOS isoforms to mitochondrial density and PGC-1alpha expression in striated muscles of mice. Nitric Oxide 2018; 77:35-43. [PMID: 29678764 DOI: 10.1016/j.niox.2018.04.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Revised: 04/10/2018] [Accepted: 04/16/2018] [Indexed: 01/16/2023]
Abstract
The expression of neuronal NO synthase (nNOS) alpha- and beta-isoforms in skeletal muscle is well documented but only little information is available about their regulation/functions. Using different mouse models, we now assessed whether the expression of nNOS-isoforms in muscle fibers is related to mitochondria content/activity and regulated by peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha). Catalytic histochemistry revealed highest nNOS-concentrations to be present in type-2 oxidative muscle fibers. Differences in mitochondrial density between nNOS-KO-mice and WT-littermates established by morphometry after transmission electron microscopy were significant in the oxidative portion of the tibialis anterior muscle (TA) but not in rectus femoris muscle (RF) indicating an nNOS-dependent mitochondrial pool in TA. Quantitative immunoblotting displayed the nNOS alpha-isoform to preponderate in those striated muscles of C57BL/6-mice that comprise of many type-2 oxidative fibers, e.g. TA, while roughly even levels of the two nNOS-isoforms were expressed in those muscles that mainly consist of type-2 glycolytic fibers, e.g. RF. Differences in citrate synthase-activity in muscle homogenates between nNOS-KO-mice and WT-littermates were positively related to nNOS alpha-isoform levels. In transgenic-mice over-expressing muscular PGC-1alpha compared to WT-littermates, immunoblotting revealed a significant shift in nNOS-expression in favor of the alpha-isoform in six out of eight striated muscles (exceptions: soleus muscle and tongue) without consistent relationship to changes in the expression of mitochondrial markers. In summary, our study demonstrated the nNOS alpha-isoform expression to be related to mitochondrial content/activity and to be up-regulated by up-stream PGC-1alpha in striated muscles, particularly in those enriched with type-2 oxidative fibers implying a functional convergence of the two signaling systems in these fibers.
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32
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Duan D. Micro-Dystrophin Gene Therapy Goes Systemic in Duchenne Muscular Dystrophy Patients. Hum Gene Ther 2018; 29:733-736. [PMID: 29463117 DOI: 10.1089/hum.2018.012] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Whole-body systemic gene therapy is likely the most effective way to reduce greatly the disease burden of Duchenne muscular dystrophy (DMD), an X-linked inherited muscle disease that leads to premature death in early adulthood. Genetically, DMD is due to null mutation of the dystrophin gene, one of the largest genes in the genome. Recent studies have shown highly promising improvements in animal models with intravascular delivery of the engineered micro-dystrophin gene by adeno-associated virus (AAV). Several human trials are now started to advance AAV micro-dystrophin therapy to DMD patients. This is a historical moment for the entire field. Results from these trials will shape the future of neuromuscular disease gene therapy.
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Affiliation(s)
- Dongsheng Duan
- 1 Department of Molecular Microbiology and Immunology, University of Missouri , Columbia, Missouri.,2 Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri , Columbia, Missouri.,3 Department of Neurology, School of Medicine, University of Missouri , Columbia, Missouri.,4 Department of Bioengineering, University of Missouri , Columbia, Missouri
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33
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Wasala NB, Shin JH, Lai Y, Yue Y, Montanaro F, Duan D. Cardiac-Specific Expression of ΔH2-R15 Mini-Dystrophin Normalized All Electrocardiogram Abnormalities and the End-Diastolic Volume in a 23-Month-Old Mouse Model of Duchenne Dilated Cardiomyopathy. Hum Gene Ther 2018; 29:737-748. [PMID: 29433343 DOI: 10.1089/hum.2017.144] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Heart disease is a major health threat for Duchenne/Becker muscular dystrophy patients and carriers. Expression of a 6-8 kb mini-dystrophin gene in the heart holds promise to change the disease course dramatically. However, the mini-dystrophin gene cannot be easily studied with adeno-associated virus (AAV) gene delivery because the size of the minigene exceeds AAV packaging capacity. Cardiac protection of the ΔH2-R19 minigene was previously studied using the cardiac-specific transgenic approach. Although this minigene fully normalized skeletal muscle force, it only partially corrected electrocardiogram and heart hemodynamics in dystrophin-null mdx mice that had moderate cardiomyopathy. This study evaluated the ΔH2-R15 minigene using the same transgenic approach in mdx mice that had more severe cardiomyopathy. In contrast to the ΔH2-R19 minigene, the ΔH2-R15 minigene carries dystrophin spectrin-like repeats 16 to 19 (R16-19), a region that has been suggested to protect the heart in clinical studies. Cardiac expression of the ΔH2-R15 minigene normalized all aberrant electrocardiogram changes and improved hemodynamics. Importantly, it corrected the end-diastolic volume, an important diastolic parameter not rescued by ΔH2-R19 mini-dystrophin. It is concluded that that ΔH2-R15 mini-dystrophin is a superior candidate gene for heart protection. This finding has important implications in the design of the mini/micro-dystrophin gene for Duchenne cardiomyopathy therapy.
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Affiliation(s)
- Nalinda B Wasala
- 1 Department of Molecular Microbiology and Immunology, The University of Missouri , Columbia, Missouri
| | - Jin-Hong Shin
- 1 Department of Molecular Microbiology and Immunology, The University of Missouri , Columbia, Missouri
| | - Yi Lai
- 1 Department of Molecular Microbiology and Immunology, The University of Missouri , Columbia, Missouri
| | - Yongping Yue
- 1 Department of Molecular Microbiology and Immunology, The University of Missouri , Columbia, Missouri
| | - Federica Montanaro
- 2 Dubowitz Neuromuscular Centre, Molecular Neurosciences Section, Developmental Neurosciences Programme, UCL Great Ormond Street Institute of Child Health , London, United Kingdom
| | - Dongsheng Duan
- 1 Department of Molecular Microbiology and Immunology, The University of Missouri , Columbia, Missouri.,3 Department of Neurology, School of Medicine, The University of Missouri , Columbia, Missouri.,4 Department of Bioengineering, The University of Missouri , Columbia, Missouri.,5 Department of Biomedical Sciences, College of Veterinary Medicine, The University of Missouri , Columbia, Missouri
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Delalande O, Molza AE, Dos Santos Morais R, Chéron A, Pollet É, Raguenes-Nicol C, Tascon C, Giudice E, Guilbaud M, Nicolas A, Bondon A, Leturcq F, Férey N, Baaden M, Perez J, Roblin P, Piétri-Rouxel F, Hubert JF, Czjzek M, Le Rumeur E. Dystrophin's central domain forms a complex filament that becomes disorganized by in-frame deletions. J Biol Chem 2018. [PMID: 29535188 DOI: 10.1074/jbc.m117.809798] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Dystrophin, encoded by the DMD gene, is critical for maintaining plasma membrane integrity during muscle contraction events. Mutations in the DMD gene disrupting the reading frame prevent dystrophin production and result in severe Duchenne muscular dystrophy (DMD); in-frame internal deletions allow production of partly functional internally deleted dystrophin and result in less severe Becker muscular dystrophy (BMD). Many known BMD deletions occur in dystrophin's central domain, generally considered to be a monotonous rod-shaped domain based on the knowledge of spectrin family proteins. However, the effects caused by these deletions, ranging from asymptomatic to severe BMD, argue against the central domain serving only as a featureless scaffold. We undertook structural studies combining small-angle X-ray scattering and molecular modeling in an effort to uncover the structure of the central domain, as dystrophin has been refractory to characterization. We show that this domain appears to be a tortuous and complex filament that is profoundly disorganized by the most severe BMD deletion (loss of exons 45-47). Despite the preservation of large parts of the binding site for neuronal nitric oxide synthase (nNOS) in this deletion, computational approaches failed to recreate the association of dystrophin with nNOS. This observation is in agreement with a strong decrease of nNOS immunolocalization in muscle biopsies, a parameter related to the severity of BMD phenotypes. The structural description of the whole dystrophin central domain we present here is a first necessary step to improve the design of microdystrophin constructs toward the goal of a successful gene therapy for DMD.
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Affiliation(s)
- Olivier Delalande
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France,
| | - Anne-Elisabeth Molza
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France
| | - Raphael Dos Santos Morais
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France.,the Synchrotron SOLEIL, 91190 Saint Aubin, France.,the Laboratoire Léon-Brillouin, UMR 12 CEA-CNRS, Université Paris-Saclay, CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France
| | - Angélique Chéron
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France
| | - Émeline Pollet
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France
| | - Céline Raguenes-Nicol
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France
| | - Christophe Tascon
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France
| | - Emmanuel Giudice
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France
| | - Marine Guilbaud
- the Sorbonne Universités UPMC-INSERM-UMRS 97-CNRS FRE 3617, Institut de Myologie, 75013 Paris, France
| | - Aurélie Nicolas
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France
| | - Arnaud Bondon
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France.,the Université Rennes, CNRS, Institut des Sciences Chimiques de Rennes-UMR 6226, PRISM, 35000 Rennes, France
| | - France Leturcq
- the Sorbonne Universités UPMC-INSERM-UMRS 97-CNRS FRE 3617, Institut de Myologie, 75013 Paris, France.,the AP-HP, Groupe Hospitalier Cochin-Broca-Hôtel Dieu, Laboratoire de Biochimie et Génétique Moléculaire, 75014 Paris, France
| | - Nicolas Férey
- the CNRS UPR3251, Université Paris XI, 91403 Orsay Cedex, France
| | - Marc Baaden
- the CNRS UPR9080, Université Paris Diderot, Sorbonne Paris Cité, 75005 Paris, France
| | - Javier Perez
- the Synchrotron SOLEIL, 91190 Saint Aubin, France
| | - Pierre Roblin
- the Synchrotron SOLEIL, 91190 Saint Aubin, France.,the INRA-Biopolymères, Interaction et Assemblages, 44000 Nantes, France
| | - France Piétri-Rouxel
- the Sorbonne Universités UPMC-INSERM-UMRS 97-CNRS FRE 3617, Institut de Myologie, 75013 Paris, France
| | - Jean-François Hubert
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France
| | - Mirjam Czjzek
- the Sorbonne Universités, UPMC Université Paris 06, 75006 Paris, France, and.,the CNRS UMR 8227, Integrative Biology of Marine Models, 29688 Roscoff Cedex, France
| | - Elisabeth Le Rumeur
- From the Université de Rennes, CNRS, Institut de Génétique et Développement de Rennes-UMR 6290, 35000 Rennes, France
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Belanto JJ, Olthoff JT, Mader TL, Chamberlain CM, Nelson DM, McCourt PM, Talsness DM, Gundersen GG, Lowe DA, Ervasti JM. Independent variability of microtubule perturbations associated with dystrophinopathy. Hum Mol Genet 2018; 25:4951-4961. [PMID: 28171583 DOI: 10.1093/hmg/ddw318] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 08/15/2016] [Accepted: 09/12/2016] [Indexed: 11/14/2022] Open
Abstract
Absence of the protein dystrophin causes Duchenne muscular dystrophy. Dystrophin directly binds to microtubules in vitro, and its absence in vivo correlates with disorganization of the subsarcolemmal microtubule lattice, increased detyrosination of α-tubulin, and altered redox signaling. We previously demonstrated that the dystrophin homologue utrophin neither binds microtubules in vitro nor rescues microtubule lattice organization when overexpressed in muscles of dystrophin-deficient mdx mice. Here, we fine-mapped the dystrophin domain necessary for microtubule binding to spectrin-like repeats 20–22. We show that transgenic mdx mice expressing a full-length dystrophin/utrophin chimera completely lacking microtubule binding activity are surprisingly rescued for all measured dystrophic phenotypes, including full restoration of microtubule lattice organization. Conversely, despite the presence of dystrophin at the sarcolemma, β-sarcoglycan-deficient skeletal muscle presents with a disorganized and densified microtubule lattice. Finally, we show that the levels of α-tubulin detyrosination remain significantly elevated to that of mdx levels in transgenic mdx mice expressing nearly full-length dystrophin. Our results demonstrate that the microtubule-associated perturbations of mdx muscle are distinct, separable, and can vary independently from other parameters previously ascribed to dystrophin deficiency.
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Affiliation(s)
- Joseph J Belanto
- Department of Biochemistry, Molecular Biology, and Biophysics, and Program in Molecular, Cellular, Developmental Biology, and Genetics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - John T Olthoff
- Department of Biochemistry, Molecular Biology, and Biophysics, and Program in Molecular, Cellular, Developmental Biology, and Genetics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Tara L Mader
- Programs in Rehabilitation Science and Physical Therapy, Department of Physical Medicine and Rehabilitation, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Christopher M Chamberlain
- Department of Biochemistry, Molecular Biology, and Biophysics, and Program in Molecular, Cellular, Developmental Biology, and Genetics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - D'anna M Nelson
- Department of Biochemistry, Molecular Biology, and Biophysics, and Program in Molecular, Cellular, Developmental Biology, and Genetics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Preston M McCourt
- Department of Biochemistry, Molecular Biology, and Biophysics, and Program in Molecular, Cellular, Developmental Biology, and Genetics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Dana M Talsness
- Department of Biochemistry, Molecular Biology, and Biophysics, and Program in Molecular, Cellular, Developmental Biology, and Genetics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - Gregg G Gundersen
- Department of Pathology & Cell Biology, Columbia University, New York, NY, USA
| | - Dawn A Lowe
- Programs in Rehabilitation Science and Physical Therapy, Department of Physical Medicine and Rehabilitation, University of Minnesota - Twin Cities, Minneapolis, MN, USA
| | - James M Ervasti
- Department of Biochemistry, Molecular Biology, and Biophysics, and Program in Molecular, Cellular, Developmental Biology, and Genetics, University of Minnesota - Twin Cities, Minneapolis, MN, USA
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36
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Costas-Insua C, Merino-Gracia J, Aicart-Ramos C, Rodríguez-Crespo I. Subcellular Targeting of Nitric Oxide Synthases Mediated by Their N-Terminal Motifs. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2017; 111:165-195. [PMID: 29459031 DOI: 10.1016/bs.apcsb.2017.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
From a catalytic point of view, the three mammalian nitric oxide synthases (NOSs) function in an almost identical way. The N-terminal oxygenase domain catalyzes the conversion of l-arginine to l-citrulline plus ·NO in two sequential oxidation steps. Once l-arginine binds to the active site positioned above the heme moiety, two consecutive monooxygenation reactions take place. In the first step, l-arginine is hydroxylated to make Nω-hydroxy-l-arginine in a process that requires 1 molecule of NADPH and 1 molecule of O2 per mol of l-arginine reacted. In the second step, Nω-hydroxy-l-arginine, never leaving the active site, is oxidized to ·NO plus l-citrulline and 1 molecule of O2 and 0.5 molecules of NADPH are consumed. Since nitric oxide is an important signaling molecule that participates in a number of biological processes, including neurotransmission, vasodilation, and immune response, synthesis and release of ·NO in vivo must be exquisitely regulated both in time and in space. Hence, NOSs have evolved introducing in their amino acid sequences subcellular targeting motifs, most of them located at their N-termini. Deletion studies performed on recombinant, purified NOSs have revealed that part of the N-terminus of all three NOS can be eliminated with the resulting mutant enzymes still being catalytically active. Likewise, NOS isoforms lacking part of their N-terminus when transfected in cells render mislocalized, active proteins. In this review we will comment on the current knowledge of these subcellular targeting signals present in nNOS, iNOS, and eNOS.
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Kodippili K, Hakim CH, Pan X, Yang HT, Yue Y, Zhang Y, Shin JH, Yang NN, Duan D. Dual AAV Gene Therapy for Duchenne Muscular Dystrophy with a 7-kb Mini-Dystrophin Gene in the Canine Model. Hum Gene Ther 2017; 29:299-311. [PMID: 28793798 DOI: 10.1089/hum.2017.095] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Dual adeno-associated virus (AAV) technology was developed in 2000 to double the packaging capacity of the AAV vector. The proof of principle has been demonstrated in various mouse models. Yet, pivotal evidence is lacking in large animal models of human diseases. Here we report expression of a 7-kb canine ΔH2-R15 mini-dystrophin gene using a pair of dual AAV vectors in the canine model of Duchenne muscular dystrophy (DMD). The ΔH2-R15 minigene is by far the most potent synthetic dystrophin gene engineered for DMD gene therapy. We packaged minigene dual vectors in Y731F tyrosine-modified AAV-9 and delivered to the extensor carpi ulnaris muscle of a 12-month-old affected dog at the dose of 2 × 1013 viral genome particles/vector/muscle. Widespread mini-dystrophin expression was observed 2 months after gene transfer. The missing dystrophin-associated glycoprotein complex was restored. Treatment also reduced muscle degeneration and fibrosis and improved myofiber size distribution. Importantly, dual AAV therapy greatly protected the muscle from eccentric contraction-induced force loss. Our data provide the first clear evidence that dual AAV therapy can be translated to a diseased large mammal. Further development of dual AAV technology may lead to effective therapies for DMD and many other diseases in human patients.
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Affiliation(s)
- Kasun Kodippili
- 1 Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri , Columbia, Missouri
| | - Chady H Hakim
- 1 Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri , Columbia, Missouri.,2 National Center for Advancing Translational Sciences , Bethesda, Maryland
| | - Xiufang Pan
- 1 Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri , Columbia, Missouri
| | - Hsiao T Yang
- 1 Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri , Columbia, Missouri.,3 Department of Biomedical Sciences, College of Veterinary Medicine, The University of Missouri , Columbia, Missouri
| | - Yongping Yue
- 1 Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri , Columbia, Missouri
| | - Yadong Zhang
- 1 Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri , Columbia, Missouri
| | - Jin-Hong Shin
- 1 Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri , Columbia, Missouri
| | - N Nora Yang
- 2 National Center for Advancing Translational Sciences , Bethesda, Maryland
| | - Dongsheng Duan
- 1 Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri , Columbia, Missouri.,3 Department of Biomedical Sciences, College of Veterinary Medicine, The University of Missouri , Columbia, Missouri.,4 Department of Neurology, School of Medicine, The University of Missouri , Columbia, Missouri.,5 Department of Bioengineering, The University of Missouri , Columbia, Missouri
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38
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Hakim CH, Wasala NB, Pan X, Kodippili K, Yue Y, Zhang K, Yao G, Haffner B, Duan SX, Ramos J, Schneider JS, Yang NN, Chamberlain JS, Duan D. A Five-Repeat Micro-Dystrophin Gene Ameliorated Dystrophic Phenotype in the Severe DBA/2J-mdx Model of Duchenne Muscular Dystrophy. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2017; 6:216-230. [PMID: 28932757 PMCID: PMC5596503 DOI: 10.1016/j.omtm.2017.06.006] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 06/24/2017] [Indexed: 02/07/2023]
Abstract
Micro-dystrophins are highly promising candidates for treating Duchenne muscular dystrophy, a lethal muscle disease caused by dystrophin deficiency. Here, we report robust disease rescue in the severe DBA/2J-mdx model with a neuronal nitric oxide synthase (nNOS)-binding micro-dystrophin vector. 2 × 1013 vector genome particles/mouse of the vector were delivered intravenously to 10-week-old mice and were evaluated at 6 months of age. Saturated micro-dystrophin expression was detected in all skeletal muscles and the heart and restored the dystrophin-associated glycoprotein complex and nNOS. In skeletal muscle, therapy substantially reduced fibrosis and calcification and significantly attenuated inflammation. Centronucleation was significantly decreased in the tibialis anterior (TA) and extensor digitorum longus (EDL) muscles but not in the quadriceps. Muscle function was normalized in the TA and significantly improved in the EDL muscle. Heart histology and function were also evaluated. Consistent with the literature, DBA/2J-mdx mice showed myocardial calcification and fibrosis and cardiac hemodynamics was compromised. Surprisingly, similar myocardial pathology and hemodynamic defects were detected in control DBA/2J mice. As a result, interpretation of the cardiac data proved difficult due to the confounding phenotype in control DBA/2J mice. Our results support further development of this microgene vector for clinical translation. Further, DBA/2J-mdx mice are not good models for Duchenne cardiomyopathy.
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Affiliation(s)
- Chady H. Hakim
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
- National Center for Advancing Translational Sciences (NCATS), Bethesda, MD 20892, USA
| | - Nalinda B. Wasala
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Xiufang Pan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Kasun Kodippili
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Yongping Yue
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Keqing Zhang
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Gang Yao
- Department of Bioengineering, University of Missouri, Columbia, MO 65212, USA
| | - Brittney Haffner
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Sean X. Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Julian Ramos
- Department of Neurology, Wellstone Muscular Dystrophy Research Center, University of Washington, Seattle, WA 98105, USA
| | | | - N. Nora Yang
- National Center for Advancing Translational Sciences (NCATS), Bethesda, MD 20892, USA
| | - Jeffrey S. Chamberlain
- Department of Neurology, Wellstone Muscular Dystrophy Research Center, University of Washington, Seattle, WA 98105, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
- Department of Bioengineering, University of Missouri, Columbia, MO 65212, USA
- Department of Neurology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO 65212, USA
- Corresponding author: Dongsheng Duan, PhD, Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, One Hospital Dr., Columbia, MO 65212, USA.
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Nance ME, Hakim CH, Yang NN, Duan D. Nanotherapy for Duchenne muscular dystrophy. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2017; 10. [PMID: 28398005 DOI: 10.1002/wnan.1472] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 02/09/2017] [Accepted: 03/11/2017] [Indexed: 12/14/2022]
Abstract
Duchenne muscular dystrophy (DMD) is a lethal X-linked childhood muscle wasting disease caused by mutations in the dystrophin gene. Nanobiotechnology-based therapies (such as synthetic nanoparticles and naturally existing viral and nonviral nanoparticles) hold great promise to replace and repair the mutated dystrophin gene and significantly change the disease course. While a majority of DMD nanotherapies are still in early preclinical development, several [such as adeno-associated virus (AAV)-mediated systemic micro-dystrophin gene therapy] are advancing for phase I clinical trials. Recent regulatory approval of Ataluren (a nonsense mutation read-through chemical) in Europe and Exondys51 (an exon-skipping antisense oligonucleotide drug) in the United States shall offer critical insight in how to move DMD nanotherapy to human patients. Progress in novel, optimized nano-delivery systems may further improve emerging molecular therapeutic modalities for DMD. Despite these progresses, DMD nanotherapy faces a number of unique challenges. Specifically, the dystrophin gene is one of the largest genes in the genome while nanoparticles have an inherent size limitation per definition. Furthermore, muscle is the largest tissue in the body and accounts for 40% of the body mass. How to achieve efficient bodywide muscle targeting in human patients with nanomedication remains a significant translational hurdle. New creative approaches in the design of the miniature micro-dystrophin gene, engineering of muscle-specific synthetic AAV capsids, and novel nanoparticle-mediated exon-skipping are likely to result in major breakthroughs in DMD therapy. WIREs Nanomed Nanobiotechnol 2018, 10:e1472. doi: 10.1002/wnan.1472 This article is categorized under: Biology-Inspired Nanomaterials > Protein and Virus-Based Structures Therapeutic Approaches and Drug Discovery > Emerging Technologies.
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Affiliation(s)
- Michael E Nance
- Department of Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO, USA
| | - Chady H Hakim
- Department of Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO, USA.,National Center for Advancing Translational Sciences, NIH, Rockville, MD, USA
| | - N Nora Yang
- National Center for Advancing Translational Sciences, NIH, Rockville, MD, USA
| | - Dongsheng Duan
- Department of Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO, USA.,Department of Neurology, University of Missouri, Columbia, MO, USA.,Department of Bioengineering, University of Missouri, Columbia, MO, USA.,Department of Biomedical Sciences, University of Missouri, Columbia, MO, USA
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40
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Johnstone VPA, Viola HM, Hool LC. Dystrophic Cardiomyopathy-Potential Role of Calcium in Pathogenesis, Treatment and Novel Therapies. Genes (Basel) 2017; 8:genes8040108. [PMID: 28338606 PMCID: PMC5406855 DOI: 10.3390/genes8040108] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 03/16/2017] [Accepted: 03/21/2017] [Indexed: 01/06/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is caused by defects in the DMD gene and results in progressive wasting of skeletal and cardiac muscle due to an absence of functional dystrophin. Cardiomyopathy is prominent in DMD patients, and contributes significantly to mortality. This is particularly true following respiratory interventions that reduce death rate and increase ambulation and consequently cardiac load. Cardiomyopathy shows an increasing prevalence with age and disease progression, and over 95% of patients exhibit dilated cardiomyopathy by the time they reach adulthood. Development of the myopathy is complex, and elevations in intracellular calcium, functional muscle ischemia, and mitochondrial dysfunction characterise the pathophysiology. Current therapies are limited to treating symptoms of the disease and there is therefore an urgent need to treat the underlying genetic defect. Several novel therapies are outlined here, and the unprecedented success of phosphorodiamidate morpholino oligomers (PMOs) in preclinical and clinical studies is overviewed.
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Affiliation(s)
- Victoria P A Johnstone
- School of Human Sciences, The University of Western Australia, Crawley, WA 6009, Australia.
| | - Helena M Viola
- School of Human Sciences, The University of Western Australia, Crawley, WA 6009, Australia.
| | - Livia C Hool
- School of Human Sciences, The University of Western Australia, Crawley, WA 6009, Australia.
- Victor Chang Cardiac Research Institute, Sydney, NSW 2010, Australia.
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41
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Chen-Izu Y, Izu LT. Mechano-chemo-transduction in cardiac myocytes. J Physiol 2017; 595:3949-3958. [PMID: 28098356 DOI: 10.1113/jp273101] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 12/15/2016] [Indexed: 12/31/2022] Open
Abstract
The heart has the ability to adjust to changing mechanical loads. The Frank-Starling law and the Anrep effect describe exquisite intrinsic mechanisms the heart has for autoregulating the force of contraction to maintain cardiac output under changes of preload and afterload. Although these mechanisms have been known for more than a century, their cellular and molecular underpinnings are still debated. How does the cardiac myocyte sense changes in preload or afterload? How does the myocyte adjust its response to compensate for such changes? In cardiac myocytes Ca2+ is a crucial regulator of contractile force and in this review we compare and contrast recent studies from different labs that address these two important questions. The 'dimensionality' of the mechanical milieu under which experiments are carried out provide important clues to the location of the mechanosensors and the kinds of mechanical forces they can sense and respond to. As a first approximation, sensors inside the myocyte appear to modulate reactive oxygen species while sensors on the cell surface appear to also modulate nitric oxide signalling; both signalling pathways affect Ca2+ handling. Undoubtedly, further studies will add layers to this simplified picture. Clarifying the intimate links from cellular mechanics to reactive oxygen species and nitric oxide signalling and to Ca2+ handling will deepen our understanding of the Frank-Starling law and the Anrep effect, and also provide a unified view on how arrhythmias may arise in seemingly disparate diseases that have in common altered myocyte mechanics.
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Affiliation(s)
- Ye Chen-Izu
- Department of Pharmacology, University of California, Davis, CA, 95616, USA.,Department of Biomedical Engineering, University of California, Davis, CA, 95616, USA.,Department of Internal Medicine/Division of Cardiology, University of California, Davis, CA, 95616, USA
| | - Leighton T Izu
- Department of Pharmacology, University of California, Davis, CA, 95616, USA
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42
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Delalande O, Czogalla A, Hubert JF, Sikorski A, Le Rumeur E. Dystrophin and Spectrin, Two Highly Dissimilar Sisters of the Same Family. Subcell Biochem 2017; 82:373-403. [PMID: 28101868 DOI: 10.1007/978-3-319-49674-0_12] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Dystrophin and Spectrin are two proteins essential for the organization of the cytoskeleton and for the stabilization of membrane cells. The comparison of these two sister proteins, and with the dystrophin homologue utrophin, enables us to emphasise that, despite a similar topology with common subdomains and a common structural basis of a three-helix coiled-coil, they show a large range of dissimilarities in terms of genetics, cell expression and higher level structural organisation. Interactions with cellular partners, including proteins and membrane phospholipids, also show both strikingly similar and very different behaviours. The differences between dystrophin and spectrin are also illustrated by the large variety of pathological anomalies emerging from the dysfunction or the absence of these proteins, showing that they are keystones in their function of providing a scaffold that sustains cell structure.
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Affiliation(s)
- Olivier Delalande
- Institut de Génétique et Développement de Rennes, UMR CNRS 6290, Université de Rennes 1, Rennes, France.
| | - Aleksander Czogalla
- Biotechnology Faculty, Department of Cytobiochemistry, University of Wrocław, ul. joliot-Curie 14a, 50-383, Wroclaw, Poland
| | - Jean-François Hubert
- Institut de Génétique et Développement de Rennes, UMR CNRS 6290, Université de Rennes 1, Rennes, France
| | - Aleksander Sikorski
- Biotechnology Faculty, Department of Cytobiochemistry, University of Wrocław, ul. joliot-Curie 14a, 50-383, Wroclaw, Poland
| | - Elisabeth Le Rumeur
- Institut de Génétique et Développement de Rennes, UMR CNRS 6290, Université de Rennes 1, Rennes, France
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43
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Reza M, Laval SH, Roos A, Carr S, Lochmüller H. Optimization of Internally Deleted Dystrophin Constructs. Hum Gene Ther Methods 2016; 27:174-186. [PMID: 27477497 DOI: 10.1089/hgtb.2016.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a severe, genetic muscle disease caused by the absence of the sarcolemmal protein dystrophin. Gene replacement therapy is considered a potential strategy for the treatment of DMD, aiming to restore the missing protein. Although the elements of the dystrophin molecule have been identified and studies in transgenic mdx mice have explored the importance of a number of these structural domains, the resulting modified dystrophin protein products that have been developed so far are only partially characterized in relation to their structure and function in vivo. To optimize a dystrophin cDNA construct for therapeutic application we designed and produced four human minidystrophins within the packaging capacity of lentiviral vectors. Two novel minidystrophins retained the centrally located neuronal nitric oxide synthase (nNOS)-anchoring domain in order to achieve sarcolemmal nNOS restoration, which is lost in most internally deleted dystrophin constructs. Functionality of the resulting truncated dystrophin proteins was investigated in muscle of adult dystrophin-deficient mdx mice followed by a battery of detailed immunohistochemical and morphometric tests. This initial assessment aimed to determine the overall suitability of various constructs for cloning into lentiviral vectors for ex vivo gene delivery to stem cells for future preclinical studies.
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Affiliation(s)
- Mojgan Reza
- 1 John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, University of Newcastle , Newcastle upon Tyne, United Kingdom
| | - Steve H Laval
- 1 John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, University of Newcastle , Newcastle upon Tyne, United Kingdom
| | - Andreas Roos
- 1 John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, University of Newcastle , Newcastle upon Tyne, United Kingdom .,2 Leibniz-Institut für Analytische Wissenschaften (ISAS) , Dortmund, Germany
| | - Stephanie Carr
- 1 John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, University of Newcastle , Newcastle upon Tyne, United Kingdom
| | - Hanns Lochmüller
- 1 John Walton Muscular Dystrophy Research Centre, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, University of Newcastle , Newcastle upon Tyne, United Kingdom
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44
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Zhao J, Kodippili K, Yue Y, Hakim CH, Wasala L, Pan X, Zhang K, Yang NN, Duan D, Lai Y. Dystrophin contains multiple independent membrane-binding domains. Hum Mol Genet 2016; 25:3647-3653. [PMID: 27378693 DOI: 10.1093/hmg/ddw210] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Revised: 06/14/2016] [Accepted: 06/27/2016] [Indexed: 01/09/2023] Open
Abstract
Dystrophin is a large sub-sarcolemmal protein. Its absence leads to Duchenne muscular dystrophy (DMD). Binding to the sarcolemma is essential for dystrophin to protect muscle from contraction-induced injury. It has long been thought that membrane binding of dystrophin depends on its cysteine-rich (CR) domain. Here, we provide in vivo evidence suggesting that dystrophin contains three additional membrane-binding domains including spectrin-like repeats (R)1-3, R10-12 and C-terminus (CT). To systematically study dystrophin membrane binding, we split full-length dystrophin into ten fragments and examined subcellular localizations of each fragment by adeno-associated virus-mediated gene transfer. In skeletal muscle, R1-3, CR domain and CT were exclusively localized at the sarcolemma. R10-12 showed both cytosolic and sarcolemmal localization. Importantly, the CR-independent membrane binding was conserved in murine and canine muscles. A critical function of the CR-mediated membrane interaction is the assembly of the dystrophin-associated glycoprotein complex (DGC). While R1-3 and R10-12 did not restore the DGC, surprisingly, CT alone was sufficient to establish the DGC at the sarcolemma. Additional studies suggest that R1-3 and CT also bind to the sarcolemma in the heart, though relatively weak. Taken together, our study provides the first conclusive in vivo evidence that dystrophin contains multiple independent membrane-binding domains. These structurally and functionally distinctive membrane-binding domains provide a molecular framework for dystrophin to function as a shock absorber and signaling hub. Our results not only shed critical light on dystrophin biology and DMD pathogenesis, but also provide a foundation for rationally engineering minimized dystrophins for DMD gene therapy.
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Affiliation(s)
- Junling Zhao
- Department of Molecular Microbiology and Immunology, School of Medicine
| | - Kasun Kodippili
- Department of Molecular Microbiology and Immunology, School of Medicine
| | - Yongping Yue
- Department of Molecular Microbiology and Immunology, School of Medicine
| | - Chady H Hakim
- Department of Molecular Microbiology and Immunology, School of Medicine.,National Center for Advancing Translational Sciences, NIH, Rockville, MD, USA
| | - Lakmini Wasala
- Department of Molecular Microbiology and Immunology, School of Medicine
| | - Xiufang Pan
- Department of Molecular Microbiology and Immunology, School of Medicine
| | - Keqing Zhang
- Department of Molecular Microbiology and Immunology, School of Medicine
| | - Nora N Yang
- National Center for Advancing Translational Sciences, NIH, Rockville, MD, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine .,Department of Neurology, School of Medicine.,Department of Bioengineering.,Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Yi Lai
- Department of Molecular Microbiology and Immunology, School of Medicine
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45
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Merino-Gracia J, Costas-Insua C, Canales MÁ, Rodríguez-Crespo I. Insights into the C-terminal Peptide Binding Specificity of the PDZ Domain of Neuronal Nitric-oxide Synthase: CHARACTERIZATION OF THE INTERACTION WITH THE TIGHT JUNCTION PROTEIN CLAUDIN-3. J Biol Chem 2016; 291:11581-95. [PMID: 27030110 DOI: 10.1074/jbc.m116.724427] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Indexed: 11/06/2022] Open
Abstract
Neuronal nitric-oxide synthase, unlike its endothelial and inducible counterparts, displays a PDZ (PSD-95/Dlg/ZO-1) domain located at its N terminus involved in subcellular targeting. The C termini of various cellular proteins insert within the binding groove of this PDZ domain and determine the subcellular distribution of neuronal NOS (nNOS). The molecular mechanisms underlying these interactions are poorly understood because the PDZ domain of nNOS can apparently exhibit class I, class II, and class III binding specificity. In addition, it has been recently suggested that the PDZ domain of nNOS binds with very low affinity to the C termini of target proteins, and a necessary simultaneous lateral interaction must take place for binding to occur. We describe herein that the PDZ domain of nNOS can behave as a bona fide class III PDZ domain and bind to C-terminal sequences with acidic residues at the P-2 position with low micromolar binding constants. Binding to C-terminal sequences with a hydrophobic residue at the P-2 position plus an acidic residue at the P-3 position (class II) can also occur, although interactions involving residues extending up to the P-7 position mediate this type of binding. This promiscuous behavior also extends to its association to class I sequences, which must display a Glu residue at P-3 and a Thr residue at P-2 By means of site-directed mutagenesis and NMR spectroscopy, we have been able to identify the residues involved in each specific type of binding and rationalize the mechanisms used to recognize binding partners. Finally, we have analyzed the high affinity association of the PDZ domain of nNOS to claudin-3 and claudin-14, two tight junction tetraspan membrane proteins that are essential components of the paracellular barrier.
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Affiliation(s)
| | | | - María Ángeles Canales
- Química Orgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Madrid 28040, Spain
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46
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Allen DG, Whitehead NP, Froehner SC. Absence of Dystrophin Disrupts Skeletal Muscle Signaling: Roles of Ca2+, Reactive Oxygen Species, and Nitric Oxide in the Development of Muscular Dystrophy. Physiol Rev 2016; 96:253-305. [PMID: 26676145 DOI: 10.1152/physrev.00007.2015] [Citation(s) in RCA: 272] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Dystrophin is a long rod-shaped protein that connects the subsarcolemmal cytoskeleton to a complex of proteins in the surface membrane (dystrophin protein complex, DPC), with further connections via laminin to other extracellular matrix proteins. Initially considered a structural complex that protected the sarcolemma from mechanical damage, the DPC is now known to serve as a scaffold for numerous signaling proteins. Absence or reduced expression of dystrophin or many of the DPC components cause the muscular dystrophies, a group of inherited diseases in which repeated bouts of muscle damage lead to atrophy and fibrosis, and eventually muscle degeneration. The normal function of dystrophin is poorly defined. In its absence a complex series of changes occur with multiple muscle proteins showing reduced or increased expression or being modified in various ways. In this review, we will consider the various proteins whose expression and function is changed in muscular dystrophies, focusing on Ca(2+)-permeable channels, nitric oxide synthase, NADPH oxidase, and caveolins. Excessive Ca(2+) entry, increased membrane permeability, disordered caveolar function, and increased levels of reactive oxygen species are early changes in the disease, and the hypotheses for these phenomena will be critically considered. The aim of the review is to define the early damage pathways in muscular dystrophy which might be appropriate targets for therapy designed to minimize the muscle degeneration and slow the progression of the disease.
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Affiliation(s)
- David G Allen
- Sydney Medical School & Bosch Institute, University of Sydney, New South Wales, Australia; and Department of Physiology & Biophysics, University of Washington, Seattle, Washington
| | - Nicholas P Whitehead
- Sydney Medical School & Bosch Institute, University of Sydney, New South Wales, Australia; and Department of Physiology & Biophysics, University of Washington, Seattle, Washington
| | - Stanley C Froehner
- Sydney Medical School & Bosch Institute, University of Sydney, New South Wales, Australia; and Department of Physiology & Biophysics, University of Washington, Seattle, Washington
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47
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Meng J, Counsell JR, Reza M, Laval SH, Danos O, Thrasher A, Lochmüller H, Muntoni F, Morgan JE. Autologous skeletal muscle derived cells expressing a novel functional dystrophin provide a potential therapy for Duchenne Muscular Dystrophy. Sci Rep 2016; 6:19750. [PMID: 26813695 PMCID: PMC4728433 DOI: 10.1038/srep19750] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 12/17/2015] [Indexed: 12/21/2022] Open
Abstract
Autologous stem cells that have been genetically modified to express dystrophin are a possible means of treating Duchenne Muscular Dystrophy (DMD). To maximize the therapeutic effect, dystrophin construct needs to contain as many functional motifs as possible, within the packaging capacity of the viral vector. Existing dystrophin constructs used for transduction of muscle stem cells do not contain the nNOS binding site, an important functional motif within the dystrophin gene. In this proof-of-concept study, using stem cells derived from skeletal muscle of a DMD patient (mdcs) transplanted into an immunodeficient mouse model of DMD, we report that two novel dystrophin constructs, C1 (ΔR3-R13) and C2 (ΔH2-R23), can be lentivirally transduced into mdcs and produce dystrophin. These dystrophin proteins were functional in vivo, as members of the dystrophin glycoprotein complex were restored in muscle fibres containing donor-derived dystrophin. In muscle fibres derived from cells that had been transduced with construct C1, the largest dystrophin construct packaged into a lentiviral system, nNOS was restored. The combination of autologous stem cells and a lentivirus expressing a novel dystrophin construct which optimally restores proteins of the dystrophin glycoprotein complex may have therapeutic application for all DMD patients, regardless of their dystrophin mutation.
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Affiliation(s)
- Jinhong Meng
- The Dubowitz Neuromuscular Centre, Molecular Neurosciences Section, Developmental Neurosciences Programme, UCL Institute of Child Health, 30 Guilford Street, London, UK, WC1N 1EH
| | - John R Counsell
- The Dubowitz Neuromuscular Centre, Molecular Neurosciences Section, Developmental Neurosciences Programme, UCL Institute of Child Health, 30 Guilford Street, London, UK, WC1N 1EH.,UCL Cancer Institute, Paul O'Gorman Building, University College London, 72 Huntley Street, London, UK, WC1E 6BT.,Molecular and Cellular Immunology, Institute of Child Health, University College London, 30 Guilford Street, London, UK, WC1N 1EH
| | - Mojgan Reza
- John Walton Centre for Muscular Dystrophy Research, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK, NE1 3BZ
| | - Steven H Laval
- John Walton Centre for Muscular Dystrophy Research, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK, NE1 3BZ
| | - Olivier Danos
- UCL Cancer Institute, Paul O'Gorman Building, University College London, 72 Huntley Street, London, UK, WC1E 6BT
| | - Adrian Thrasher
- Molecular and Cellular Immunology, Institute of Child Health, University College London, 30 Guilford Street, London, UK, WC1N 1EH
| | - Hanns Lochmüller
- John Walton Centre for Muscular Dystrophy Research, MRC Centre for Neuromuscular Diseases, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK, NE1 3BZ
| | - Francesco Muntoni
- The Dubowitz Neuromuscular Centre, Molecular Neurosciences Section, Developmental Neurosciences Programme, UCL Institute of Child Health, 30 Guilford Street, London, UK, WC1N 1EH
| | - Jennifer E Morgan
- The Dubowitz Neuromuscular Centre, Molecular Neurosciences Section, Developmental Neurosciences Programme, UCL Institute of Child Health, 30 Guilford Street, London, UK, WC1N 1EH
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Yue Y, Binalsheikh IM, Leach SB, Domeier TL, Duan D. Prospect of gene therapy for cardiomyopathy in hereditary muscular dystrophy. Expert Opin Orphan Drugs 2015; 4:169-183. [PMID: 27340611 DOI: 10.1517/21678707.2016.1124039] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Cardiac involvement is a common feature in muscular dystrophies. It presents as heart failure and/or arrhythmia. Traditionally, dystrophic cardiomyopathy is treated with symptom-relieving medications. Identification of disease-causing genes and investigation on pathogenic mechanisms have opened new opportunities to treat dystrophic cardiomyopathy with gene therapy. Replacing/repairing the mutated gene and/or targeting the pathogenic process/mechanisms using alternative genes may attenuate heart disease in muscular dystrophies. AREAS COVERED Duchenne muscular dystrophy is the most common muscular dystrophy. Duchenne cardiomyopathy has been the primary focus of ongoing dystrophic cardiomyopathy gene therapy studies. Here, we use Duchenne cardiomyopathy gene therapy to showcase recent developments and to outline the path forward. We also discuss gene therapy status for cardiomyopathy associated with limb-girdle and congenital muscular dystrophies, and myotonic dystrophy. EXPERT OPINION Gene therapy for dystrophic cardiomyopathy has taken a slow but steady path forward. Preclinical studies over the last decades have addressed many fundamental questions. Adeno-associated virus-mediated gene therapy has significantly improved the outcomes in rodent models of Duchenne and limb girdle muscular dystrophies. Validation of these encouraging results in large animal models will pave the way to future human trials.
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Affiliation(s)
- Yongping Yue
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri
| | | | - Stacey B Leach
- Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri
| | - Timothy L Domeier
- Department of Medical Physiology and Pharmacology, School of Medicine, University of Missouri
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri; Department of Neurology, School of Medicine, University of Missouri
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49
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McGreevy JW, Hakim CH, McIntosh MA, Duan D. Animal models of Duchenne muscular dystrophy: from basic mechanisms to gene therapy. Dis Model Mech 2015; 8:195-213. [PMID: 25740330 PMCID: PMC4348559 DOI: 10.1242/dmm.018424] [Citation(s) in RCA: 316] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a progressive muscle-wasting disorder. It is caused by loss-of-function mutations in the dystrophin gene. Currently, there is no cure. A highly promising therapeutic strategy is to replace or repair the defective dystrophin gene by gene therapy. Numerous animal models of DMD have been developed over the last 30 years, ranging from invertebrate to large mammalian models. mdx mice are the most commonly employed models in DMD research and have been used to lay the groundwork for DMD gene therapy. After ~30 years of development, the field has reached the stage at which the results in mdx mice can be validated and scaled-up in symptomatic large animals. The canine DMD (cDMD) model will be excellent for these studies. In this article, we review the animal models for DMD, the pros and cons of each model system, and the history and progress of preclinical DMD gene therapy research in the animal models. We also discuss the current and emerging challenges in this field and ways to address these challenges using animal models, in particular cDMD dogs.
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Affiliation(s)
- Joe W McGreevy
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Chady H Hakim
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Mark A McIntosh
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO 65212, USA Department of Neurology, School of Medicine, University of Missouri, Columbia, MO 65212, USA
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50
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Rebolledo DL, Kim MJ, Whitehead NP, Adams ME, Froehner SC. Sarcolemmal targeting of nNOSμ improves contractile function of mdx muscle. Hum Mol Genet 2015; 25:158-66. [PMID: 26604149 DOI: 10.1093/hmg/ddv466] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 11/09/2015] [Indexed: 11/13/2022] Open
Abstract
Nitric oxide (NO) is a key regulator of skeletal muscle function and metabolism, including vasoregulation, mitochondrial function, glucose uptake, fatigue and excitation-contraction coupling. The main generator of NO in skeletal muscle is the muscle-specific form of neuronal nitric oxide synthase (nNOSμ) produced by the NOS1 gene. Skeletal muscle nNOSμ is predominantly localized at the sarcolemma by interaction with the dystrophin protein complex (DPC). In Duchenne muscular dystrophy (DMD), loss of dystrophin leads to the mislocalization of nNOSμ from the sarcolemma to the cytosol. This perturbation has been shown to impair contractile function and cause muscle fatigue in dystrophic (mdx) mice. Here, we investigated the effect of restoring sarcolemmal nNOSμ on muscle contractile function in mdx mice. To achieve this, we designed a modified form of nNOSμ (NOS-M) that is targeted to the sarcolemma by palmitoylation, even in the absence of the DPC. When expressed specifically in mdx skeletal muscle, NOS-M significantly attenuates force loss owing to damaging eccentric contractions and repetitive isometric contractions (fatigue), while also improving force recovery after fatigue. Expression of unmodified nNOSμ at similar levels does not lead to sarcolemmal association and fails to improve muscle function. Aside from the benefits of sarcolemmal-localized NO production, NOS-M also increased the surface membrane levels of utrophin and other DPC proteins, including β-dystroglycan, α-syntrophin and α-dystrobrevin in mdx muscle. These results suggest that the expression of NOS-M in skeletal muscle may be therapeutically beneficial in DMD and other muscle diseases characterized by the loss of nNOSμ from the sarcolemma.
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Affiliation(s)
- Daniela L Rebolledo
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7290, USA and Departamento de Biología Celular y Molecular, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Min Jeong Kim
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7290, USA and
| | - Nicholas P Whitehead
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7290, USA and
| | - Marvin E Adams
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7290, USA and
| | - Stanley C Froehner
- Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-7290, USA and
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