1
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Roger AL, Biswas DD, Huston ML, Le D, Bailey AM, Pucci LA, Shi Y, Robinson-Hamm J, Gersbach CA, ElMallah MK. Respiratory characterization of a humanized Duchenne muscular dystrophy mouse model. Respir Physiol Neurobiol 2024; 326:104282. [PMID: 38782084 DOI: 10.1016/j.resp.2024.104282] [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: 03/19/2024] [Revised: 05/07/2024] [Accepted: 05/17/2024] [Indexed: 05/25/2024]
Abstract
Duchenne muscular dystrophy (DMD) is the most common X-linked disease. DMD is caused by a lack of dystrophin, a critical structural protein in striated muscle. Dystrophin deficiency leads to inflammation, fibrosis, and muscle atrophy. Boys with DMD have progressive muscle weakness within the diaphragm that results in respiratory failure in the 2nd or 3rd decade of life. The most common DMD mouse model - the mdx mouse - is not sufficient for evaluating genetic medicines that specifically target the human DMD (hDMD) gene sequence. Therefore, a novel transgenic mouse carrying the hDMD gene with an exon 52 deletion was created (hDMDΔ52;mdx). We characterized the respiratory function and pathology in this model using whole body plethysmography, histology, and immunohistochemistry. At 6-months-old, hDMDΔ52;mdx mice have reduced maximal respiration, neuromuscular junction pathology, and fibrosis throughout the diaphragm, which worsens at 12-months-old. In conclusion, the hDMDΔ52;mdx exhibits moderate respiratory pathology, and serves as a relevant animal model to study the impact of novel genetic therapies, including gene editing, on respiratory function.
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Affiliation(s)
- Angela L Roger
- Department of Pediatrics, Duke University, Durham, NC, USA
| | | | | | - Davina Le
- Department of Pediatrics, Duke University, Durham, NC, USA
| | - Aidan M Bailey
- Department of Pediatrics, Duke University, Durham, NC, USA
| | - Logan A Pucci
- Department of Pediatrics, Duke University, Durham, NC, USA
| | - Yihan Shi
- Department of Pediatrics, Duke University, Durham, NC, USA
| | | | | | - Mai K ElMallah
- Department of Pediatrics, Duke University, Durham, NC, USA.
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2
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Alizadeh F, Abraghan YJ, Farrokhi S, Yousefi Y, Mirahmadi Y, Eslahi A, Mojarrad M. Production of Duchenne muscular dystrophy cellular model using CRISPR-Cas9 exon deletion strategy. Mol Cell Biochem 2024; 479:1027-1040. [PMID: 37289342 DOI: 10.1007/s11010-023-04759-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 05/03/2023] [Indexed: 06/09/2023]
Abstract
Duchenne Muscular Dystrophy (DMD) is a progressive muscle wasting disorder caused by loss-of-function mutations in the dystrophin gene. Although the search for a definitive cure has failed to date, extensive efforts have been made to introduce effective therapeutic strategies. Gene editing technology is a great revolution in biology, having an immediate application in the generation of research models. DMD muscle cell lines are reliable sources to evaluate and optimize therapeutic strategies, in-depth study of DMD pathology, and screening the effective drugs. However, only a few immortalized muscle cell lines with DMD mutations are available. In addition, obtaining muscle cells from patients also requires an invasive muscle biopsy. Mostly DMD variants are rare, making it challenging to identify a patient with a particular mutation for a muscle biopsy. To overcome these challenges and generate myoblast cultures, we optimized a CRISPR/Cas9 gene editing approach to model the most common DMD mutations that include approximately 28.2% of patients. GAP-PCR and sequencing results show the ability of the CRISPR-Cas9 system to efficient deletion of mentioned exons. We showed producing truncated transcript due to the targeted deletion by RT-PCR and sequencing. Finally, mutation-induced disruption of dystrophin protein expression was confirmed by western blotting. All together, we successfully created four immortalized DMD muscle cell lines and showed the efficacy of the CRISPR-Cas9 system for the generation of immortalized DMD cell models with the targeted deletions.
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Affiliation(s)
- Farzaneh Alizadeh
- Department of Medical Genetics and Molecular Medicine, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Yousef Jafari Abraghan
- Department of Medical Genetics and Molecular Medicine, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Shima Farrokhi
- Department of Medical Genetics and Molecular Medicine, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Yasamin Yousefi
- Department of Biochemistry, Mashhad University of Ferdowsi, Mashhad, Iran
| | - Yeganeh Mirahmadi
- Department of Biochemistry, Genetics and Molecular Biology, Islamic Azad University, Mashhad, Iran
| | - Atieh Eslahi
- Department of Medical Genetics and Molecular Medicine, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
| | - Majid Mojarrad
- Department of Medical Genetics and Molecular Medicine, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
- Genetic Center of Khorasan Razavi, Mashhad, Iran.
- Medical Genetics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
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3
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Engelbeen S, O'Reilly D, Van De Vijver D, Verhaart I, van Putten M, Hariharan V, Hassler M, Khvorova A, Damha MJ, Aartsma-Rus A. Challenges of Assessing Exon 53 Skipping of the Human DMD Transcript with Locked Nucleic Acid-Modified Antisense Oligonucleotides in a Mouse Model for Duchenne Muscular Dystrophy. Nucleic Acid Ther 2023; 33:348-360. [PMID: 38010230 DOI: 10.1089/nat.2023.0038] [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] [Indexed: 11/29/2023] Open
Abstract
Antisense oligonucleotide (AON)-mediated exon skipping is a promising therapeutic approach for Duchenne muscular dystrophy (DMD) patients to restore dystrophin expression by reframing the disrupted open reading frame of the DMD transcript. However, the treatment efficacy of the already conditionally approved AONs remains low. Aiming to optimize AON efficiency, we assessed exon 53 skipping of the DMD transcript with different chemically modified AONs, all with a phosphorothioate backbone: 2'-O-methyl (2'OMe), locked nucleic acid (LNA)-2'OMe, 2'-fluoro (FRNA), LNA-FRNA, αLNA-FRNA, and FANA-LNA-FRNA. Efficient exon 53 skipping was observed with the FRNA, LNA-FRNA, and LNA-2'OMe AONs in human control myoblast cultures. Weekly subcutaneous injections (50 mg/kg AON) for a duration of 6 weeks were well tolerated by hDMDdel52/mdx males. Treatment with the LNA-FRNA and LNA-2'OMe AONs resulted in pronounced exon 53 skip levels in skeletal muscles and heart up to 90%, but no dystrophin restoration was observed. This discrepancy was mainly ascribed to the strong binding nature of LNA modifications to RNA, thereby interfering with the amplification of the unskipped product resulting in artificial overamplification of the exon 53 skip product. Our study highlights that treatment effect on RNA and protein level should both be considered when assessing AON efficiency.
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Affiliation(s)
- Sarah Engelbeen
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Daniel O'Reilly
- University of Massachusetts Chan Medical School, RNA Therapeutics Institute, Worcester, Massachusetts, USA
- Department of Chemistry, McGill University, Montreal, Canada
| | - Davy Van De Vijver
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Ingrid Verhaart
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Maaike van Putten
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Vignesh Hariharan
- University of Massachusetts Chan Medical School, RNA Therapeutics Institute, Worcester, Massachusetts, USA
| | - Matthew Hassler
- University of Massachusetts Chan Medical School, RNA Therapeutics Institute, Worcester, Massachusetts, USA
| | - Anastasia Khvorova
- University of Massachusetts Chan Medical School, RNA Therapeutics Institute, Worcester, Massachusetts, USA
| | - Masad J Damha
- Department of Chemistry, McGill University, Montreal, Canada
| | - Annemieke Aartsma-Rus
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
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4
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Aartsma-Rus A, De Waele L, Houwen-Opstal S, Kirschner J, Krom YD, Mercuri E, Niks EH, Straub V, van Duyvenvoorde HA, Vroom E. The Dilemma of Choice for Duchenne Patients Eligible for Exon 51 Skipping The European Experience. J Neuromuscul Dis 2023; 10:315-325. [PMID: 36911945 DOI: 10.3233/jnd-221648] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
Abstract
Antisense oligonucleotide (ASO) mediated exon skipping aims to reframe dystrophin transcripts for patients with Duchenne muscular dystrophy (DMD). Currently 4 ASOs have been approved by the Food and Drug Administration targeting exon 45, 51 and 53 based on low level dystrophin restoration. Additional studies to confirm functional effects are ongoing. Furthermore, efforts are ongoing to increase muscle specific delivery of ASOs. Consequently, there are 5 clinical trials ongoing or planned for exon 51 skipping ASOs in Europe. While exon 51 skipping applies to the largest group of patients, DMD expert centers do not have sufficient numbers of patients or capacity to run all these trials in parallel. Even at a national level numbers may be too scarce. At the same time, some families now face the choice between participation in different clinical trials of exon 51 skipping, sometimes in addition to the choice of participating in a micro-dystrophin gene therapy trial. In this opinion paper, we outline the challenges, compare the different exon 51 skipping trials, and outline how different European centers and countries try to cope with running multiple trials in parallel for a small group of eligible patients.
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Affiliation(s)
- Annemieke Aartsma-Rus
- Leiden University Medical Center, Leiden, the Netherlands.,Duchenne Center Netherlands, the Netherlands
| | - Liesbeth De Waele
- Department of Paediatrics, University Hospitals Leuven, Leuven, Belgium.,Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - Saskia Houwen-Opstal
- Duchenne Center Netherlands, the Netherlands.,Department of Rehabilitation, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Amalia Children's Hospital, Nijmegen, the Netherlands
| | - Janbernd Kirschner
- Department of Neuropediatrics and Muscle Disorders, Medical Center - University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Yvonne D Krom
- Leiden University Medical Center, Leiden, the Netherlands.,Duchenne Center Netherlands, the Netherlands
| | - Eugenio Mercuri
- Department of Pediatric Neurology, Catholic University, Rome, Italy.,Centro Clinico Nemo, Fondazione Policlinico Agostino Gemelli IRCCS, Rome Italy
| | - Erik H Niks
- Leiden University Medical Center, Leiden, the Netherlands.,Duchenne Center Netherlands, the Netherlands
| | - Volker Straub
- John Walton Muscular Dystrophy Research Center, Newcastle University, Newcastle upon Tyne, United Kingdom
| | | | - Elizabeth Vroom
- Duchenne Center Netherlands, the Netherlands.,Duchenne Parent Project
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5
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Chey YCJ, Arudkumar J, Aartsma-Rus A, Adikusuma F, Thomas PQ. CRISPR applications for Duchenne muscular dystrophy: From animal models to potential therapies. WIREs Mech Dis 2023; 15:e1580. [PMID: 35909075 PMCID: PMC10078488 DOI: 10.1002/wsbm.1580] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 04/28/2022] [Accepted: 06/30/2022] [Indexed: 01/31/2023]
Abstract
CRISPR gene-editing technology creates precise and permanent modifications to DNA. It has significantly advanced our ability to generate animal disease models for use in biomedical research and also has potential to revolutionize the treatment of genetic disorders. Duchenne muscular dystrophy (DMD) is a monogenic muscle-wasting disease that could potentially benefit from the development of CRISPR therapy. It is commonly associated with mutations that disrupt the reading frame of the DMD gene that encodes dystrophin, an essential scaffolding protein that stabilizes striated muscles and protects them from contractile-induced damage. CRISPR enables the rapid generation of various animal models harboring mutations that closely simulates the wide variety of mutations observed in DMD patients. These models provide a platform for the testing of sequence-specific interventions like CRISPR therapy that aim to reframe or skip DMD mutations to restore functional dystrophin expression. This article is categorized under: Congenital Diseases > Genetics/Genomics/Epigenetics.
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Affiliation(s)
- Yu C J Chey
- School of Biomedicine and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia.,Genome Editing Program, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Jayshen Arudkumar
- School of Biomedicine and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia.,Genome Editing Program, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
| | - Annemieke Aartsma-Rus
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Fatwa Adikusuma
- School of Biomedicine and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia.,Genome Editing Program, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia.,CSIRO Synthetic Biology Future Science Platform, Canberra, Australia
| | - Paul Q Thomas
- School of Biomedicine and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia.,Genome Editing Program, South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia.,South Australian Genome Editing (SAGE), South Australian Health and Medical Research Institute (SAHMRI), Adelaide, South Australia, Australia
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6
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A humanized knockin mouse model of Duchenne muscular dystrophy and its correction by CRISPR-Cas9 therapeutic gene editing. MOLECULAR THERAPY - NUCLEIC ACIDS 2022; 29:525-537. [PMID: 36035749 PMCID: PMC9398917 DOI: 10.1016/j.omtn.2022.07.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 07/20/2022] [Indexed: 01/01/2023]
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7
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Polikarpova AV, Egorova TV, Bardina MV. Genetically modified animal models of hereditary diseases for testing of gene-directed therapy. RESEARCH RESULTS IN PHARMACOLOGY 2022. [DOI: 10.3897/rrpharmacology.8.82618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Disease-causing genes have been identified for many severe muscular and neurological genetic disorders. Advances in the gene therapy field offer promising solutions for drug development to treat these life-threatening conditions. Depending on how the mutation affects the function of the gene product, different gene therapy approaches may be beneficial. Gene replacement therapy is appropriate for diseases caused by mutations that result in the deficiency of the functional protein. Gene suppression strategy is suggested for disorders caused by the toxic product of the mutant gene. Splicing modulators, genome editing, and base editing techniques can be applied to disorders with different types of underlying mutations. Testing potential drugs in animal models of human diseases is an indispensable step of development. Given the specific gene therapy approach, appropriate animal models can be generated using a variety of technologies ranging from transgenesis to precise genome editing. In this review, we discuss technologies used to generate small and large animal models of the most common muscular and neurological genetic disorders. We specifically focus on animal models that were used to test gene therapies based on adeno-associated vectors and antisense nucleotides.
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8
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Lambrescu I, Popa A, Manole E, Ceafalan LC, Gaina G. Application of Droplet Digital PCR Technology in Muscular Dystrophies Research. Int J Mol Sci 2022; 23:ijms23094802. [PMID: 35563191 PMCID: PMC9099497 DOI: 10.3390/ijms23094802] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/19/2022] [Accepted: 04/25/2022] [Indexed: 11/25/2022] Open
Abstract
Although they are considered rare disorders, muscular dystrophies have a strong impact on people’s health. Increased disease severity with age, frequently accompanied by the loss of ability to walk in some people, and the lack of treatment, have directed the researchers towards the development of more effective therapeutic strategies aimed to improve the quality of life and life expectancy, slow down the progression, and delay the onset or convert a severe phenotype into a milder one. Improved understanding of the complex pathology of these diseases together with the tremendous advances in molecular biology technologies has led to personalized therapeutic procedures. Different approaches that are currently under extensive investigation require more efficient, sensitive, and less invasive methods. Due to its remarkable analytical sensitivity, droplet digital PCR has become a promising tool for accurate measurement of biomarkers that monitor disease progression and quantification of various therapeutic efficiency and can be considered a tool for non-invasive prenatal diagnosis and newborn screening. Here, we summarize the recent applications of droplet digital PCR in muscular dystrophy research and discuss the factors that should be considered to get the best performance with this technology.
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Affiliation(s)
- Ioana Lambrescu
- Laboratory of Cell Biology, Neuroscience and Experimental Myology, Victor Babes National Institute of Pathology, 050096 Bucharest, Romania; (I.L.); (A.P.); (E.M.); (L.C.C.)
- Department of Cell Biology and Histology, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Alexandra Popa
- Laboratory of Cell Biology, Neuroscience and Experimental Myology, Victor Babes National Institute of Pathology, 050096 Bucharest, Romania; (I.L.); (A.P.); (E.M.); (L.C.C.)
- Department of Animal Production and Public Health, University of Agronomic Sciences and Veterinary Medicine of Bucharest, 050097 Bucharest, Romania
| | - Emilia Manole
- Laboratory of Cell Biology, Neuroscience and Experimental Myology, Victor Babes National Institute of Pathology, 050096 Bucharest, Romania; (I.L.); (A.P.); (E.M.); (L.C.C.)
- Pathology Department, Colentina Clinical Hospital, 020125 Bucharest, Romania
| | - Laura Cristina Ceafalan
- Laboratory of Cell Biology, Neuroscience and Experimental Myology, Victor Babes National Institute of Pathology, 050096 Bucharest, Romania; (I.L.); (A.P.); (E.M.); (L.C.C.)
- Department of Cell Biology and Histology, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania
| | - Gisela Gaina
- Laboratory of Cell Biology, Neuroscience and Experimental Myology, Victor Babes National Institute of Pathology, 050096 Bucharest, Romania; (I.L.); (A.P.); (E.M.); (L.C.C.)
- Correspondence: ; Tel.: +40-21-319-2732
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9
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Development of DG9 peptide-conjugated single- and multi-exon skipping therapies for the treatment of Duchenne muscular dystrophy. Proc Natl Acad Sci U S A 2022; 119:2112546119. [PMID: 35193974 PMCID: PMC8892351 DOI: 10.1073/pnas.2112546119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/15/2021] [Indexed: 11/19/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a fatal disorder of progressive body-wide muscle weakness, considered the most common muscular dystrophy worldwide. Most patients have out-of-frame deletions in the DMD gene, leading to dystrophin absence in muscle. There is no cure for DMD, but exon skipping is emerging as a potential therapy that uses antisense oligonucleotides to convert out-of-frame to in-frame mutations, enabling the production of truncated, partially functional dystrophin. Currently approved exon skipping therapies, however, have limited applicability and efficacy. Here, we developed a more economical approach to skip DMD exons 45 to 55 (a strategy that could treat nearly half of all DMD patients) and identified DG9 peptide conjugation as a powerful way to improve exon skipping efficiencies in vivo. Duchenne muscular dystrophy (DMD) is primarily caused by out-of-frame deletions in the dystrophin gene. Exon skipping using phosphorodiamidate morpholino oligomers (PMOs) converts out-of-frame to in-frame mutations, producing partially functional dystrophin. Four single-exon skipping PMOs are approved for DMD but treat only 8 to 14% of patients each, and some exhibit poor efficacy. Alternatively, exons 45 to 55 skipping could treat 40 to 47% of all patients and is associated with improved clinical outcomes. Here, we report the development of peptide-conjugated PMOs for exons 45 to 55 skipping. Experiments with immortalized patient myotubes revealed that exons 45 to 55 could be skipped by targeting as few as five exons. We also found that conjugating DG9, a cell-penetrating peptide, to PMOs improved single-exon 51 skipping, dystrophin restoration, and muscle function in hDMDdel52;mdx mice. Local administration of a minimized exons 45 to 55–skipping DG9-PMO mixture restored dystrophin production. This study provides proof of concept toward the development of a more economical and effective exons 45 to 55–skipping DMD therapy.
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10
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Lim KRQ, Shah MNA, Woo S, Wilton-Clark H, Zhabyeyev P, Wang F, Maruyama R, Oudit GY, Yokota T. Natural History of a Mouse Model Overexpressing the Dp71 Dystrophin Isoform. Int J Mol Sci 2021; 22:ijms222312617. [PMID: 34884423 PMCID: PMC8657860 DOI: 10.3390/ijms222312617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/17/2021] [Accepted: 11/18/2021] [Indexed: 11/18/2022] Open
Abstract
Dystrophin is a 427 kDa protein that stabilizes muscle cell membranes through interactions with the cytoskeleton and various membrane-associated proteins. Loss of dystrophin as in Duchenne muscular dystrophy (DMD) causes progressive skeletal muscle weakness and cardiac dysfunction. Multiple promoters along the dystrophin gene (DMD) give rise to a number of shorter isoforms. Of interest is Dp71, a 71 kDa isoform implicated in DMD pathology by various animal and patient studies. Strong evidence supporting such a role for Dp71, however, is lacking. Here, we use del52;WT mice to understand how Dp71 overexpression affects skeletal and cardiac muscle phenotypes. Apart from the mouse Dmd gene, del52;WT mice are heterozygous for a full-length, exon 52-deleted human DMD transgene expected to only permit Dp71 expression in muscle. Thus, del52;WT mice overexpress Dp71 through both the human and murine dystrophin genes. We observed elevated Dp71 protein in del52;WT mice, significantly higher than wild-type in the heart but not the tibialis anterior. Moreover, del52;WT mice had generally normal skeletal muscle but impaired cardiac function, exhibiting significant systolic dysfunction as early as 3 months. No histological abnormalities were found in the tibialis anterior and heart. Our results suggest that Dp71 overexpression may have more detrimental effects on the heart than on skeletal muscles, providing insight into the role of Dp71 in DMD pathogenesis.
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Affiliation(s)
- Kenji Rowel Q. Lim
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2H7, Canada; (K.R.Q.L.); (M.N.A.S.); (S.W.); (H.W.-C.); (R.M.)
| | - Md Nur Ahad Shah
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2H7, Canada; (K.R.Q.L.); (M.N.A.S.); (S.W.); (H.W.-C.); (R.M.)
| | - Stanley Woo
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2H7, Canada; (K.R.Q.L.); (M.N.A.S.); (S.W.); (H.W.-C.); (R.M.)
| | - Harry Wilton-Clark
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2H7, Canada; (K.R.Q.L.); (M.N.A.S.); (S.W.); (H.W.-C.); (R.M.)
| | - Pavel Zhabyeyev
- Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2G3, Canada; (P.Z.); (F.W.)
| | - Faqi Wang
- Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2G3, Canada; (P.Z.); (F.W.)
| | - Rika Maruyama
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2H7, Canada; (K.R.Q.L.); (M.N.A.S.); (S.W.); (H.W.-C.); (R.M.)
| | - Gavin Y. Oudit
- Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2G3, Canada; (P.Z.); (F.W.)
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, AB T6G2B7, Canada
- Correspondence: (G.Y.O.); (T.Y.)
| | - Toshifumi Yokota
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2H7, Canada; (K.R.Q.L.); (M.N.A.S.); (S.W.); (H.W.-C.); (R.M.)
- Muscular Dystrophy Canada Research Chair, Edmonton, AB T6G2H7, Canada
- Correspondence: (G.Y.O.); (T.Y.)
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11
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Zhang Y, Nishiyama T, Olson EN, Bassel-Duby R. CRISPR/Cas correction of muscular dystrophies. Exp Cell Res 2021; 408:112844. [PMID: 34571006 PMCID: PMC8530959 DOI: 10.1016/j.yexcr.2021.112844] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 09/10/2021] [Accepted: 09/23/2021] [Indexed: 12/28/2022]
Abstract
Muscular dystrophies are a heterogeneous group of monogenic neuromuscular disorders which lead to progressive muscle loss and degeneration of the musculoskeletal system. The genetic causes of muscular dystrophies are well characterized, but no effective treatments have been developed so far. The discovery and application of the CRISPR/Cas system for genome editing offers a new path for disease treatment with the potential to permanently correct genetic mutations. The post-mitotic and multinucleated features of skeletal muscle provide an ideal target for CRISPR/Cas therapeutic genome editing because correction of a subpopulation of nuclei can provide benefit to the whole myofiber. In this review, we provide an overview of the CRISPR/Cas system and its derivatives in genome editing, proposing potential CRISPR/Cas-based therapies to correct diverse muscular dystrophies, and we discuss challenges for translating CRISPR/Cas genome editing to a viable therapy for permanent correction of muscular dystrophies.
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Affiliation(s)
- Yu Zhang
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Takahiko Nishiyama
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Eric N Olson
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Rhonda Bassel-Duby
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
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12
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Low human dystrophin levels prevent cardiac electrophysiological and structural remodelling in a Duchenne mouse model. Sci Rep 2021; 11:9779. [PMID: 33963238 PMCID: PMC8105358 DOI: 10.1038/s41598-021-89208-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 04/15/2021] [Indexed: 02/03/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a progressive neuromuscular disorder caused by loss of dystrophin. This lack also affects cardiac structure and function, and cardiovascular complications are a major cause of death in DMD. Newly developed therapies partially restore dystrophin expression. It is unclear whether this will be sufficient to prevent or ameliorate cardiac involvement in DMD. We here establish the cardiac electrophysiological and structural phenotype in young (2-3 months) and aged (6-13 months) dystrophin-deficient mdx mice expressing 100% human dystrophin (hDMD), 0% human dystrophin (hDMDdel52-null) or low levels (~ 5%) of human dystrophin (hDMDdel52-low). Compared to hDMD, young and aged hDMDdel52-null mice displayed conduction slowing and repolarisation abnormalities, while only aged hDMDdel52-null mice displayed increased myocardial fibrosis. Moreover, ventricular cardiomyocytes from young hDMDdel52-null animals displayed decreased sodium current and action potential (AP) upstroke velocity, and prolonged AP duration at 20% and 50% of repolarisation. Hence, cardiac electrical remodelling in hDMDdel52-null mice preceded development of structural alterations. In contrast to hDMDdel52-null, hDMDdel52-low mice showed similar electrophysiological and structural characteristics as hDMD, indicating prevention of the cardiac DMD phenotype by low levels of human dystrophin. Our findings are potentially relevant for the development of therapeutic strategies aimed at restoring dystrophin expression in DMD.
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Choi E, Koo T. CRISPR technologies for the treatment of Duchenne muscular dystrophy. Mol Ther 2021; 29:3179-3191. [PMID: 33823301 DOI: 10.1016/j.ymthe.2021.04.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 03/18/2021] [Accepted: 03/30/2021] [Indexed: 02/07/2023] Open
Abstract
The emerging clustered regularly interspaced short palindromic repeats (CRISPR)-mediated genome editing technologies have progressed remarkably in recent years, opening up the potential of precise genome editing as a therapeutic approach to treat various diseases. The CRISPR-CRISPR-associated (Cas) system is an attractive platform for the treatment of Duchenne muscular dystrophy (DMD), which is a neuromuscular disease caused by mutations in the DMD gene. CRISPR-Cas can be used to permanently repair the mutated DMD gene, leading to the expression of the encoded protein, dystrophin, in systems ranging from cells derived from DMD patients to animal models of DMD. However, the development of more efficient therapeutic approaches and delivery methods remains a great challenge for DMD. Here, we review various therapeutic strategies that use CRISPR-Cas to correct or bypass DMD mutations and discuss their therapeutic potential, as well as obstacles that lie ahead.
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Affiliation(s)
- Eunyoung Choi
- Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - Taeyoung Koo
- Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul, Republic of Korea; Department of Biomedical and Pharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul, Republic of Korea; Department of Pharmaceutical Science, College of Pharmacy, Kyung Hee University, Seoul 02447, Republic of Korea.
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