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Haque US, Yokota T. Enhancing Antisense Oligonucleotide-Based Therapeutic Delivery with DG9, a Versatile Cell-Penetrating Peptide. Cells 2023; 12:2395. [PMID: 37830609 PMCID: PMC10572411 DOI: 10.3390/cells12192395] [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: 08/26/2023] [Revised: 09/18/2023] [Accepted: 09/19/2023] [Indexed: 10/14/2023] Open
Abstract
Antisense oligonucleotide-based (ASO) therapeutics have emerged as a promising strategy for the treatment of human disorders. Charge-neutral PMOs have promising biological and pharmacological properties for antisense applications. Despite their great potential, the efficient delivery of these therapeutic agents to target cells remains a major obstacle to their widespread use. Cellular uptake of naked PMO is poor. Cell-penetrating peptides (CPPs) appear as a possibility to increase the cellular uptake and intracellular delivery of oligonucleotide-based drugs. Among these, the DG9 peptide has been identified as a versatile CPP with remarkable potential for enhancing the delivery of ASO-based therapeutics due to its unique structural features. Notably, in the context of phosphorodiamidate morpholino oligomers (PMOs), DG9 has shown promise in enhancing delivery while maintaining a favorable toxicity profile. A few studies have highlighted the potential of DG9-conjugated PMOs in DMD (Duchenne Muscular Dystrophy) and SMA (Spinal Muscular Atrophy), displaying significant exon skipping/inclusion and functional improvements in animal models. The article provides an overview of a detailed understanding of the challenges that ASOs face prior to reaching their targets and continued advances in methods to improve their delivery to target sites and cellular uptake, focusing on DG9, which aims to harness ASOs' full potential in precision medicine.
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Affiliation(s)
- Umme Sabrina Haque
- Department of Neuroscience, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Toshifumi Yokota
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
- The Friends of Garrett Cumming Research & Muscular Dystrophy Canada HM Toupin Neurological Science Research, Edmonton, AB T6G 2H7, Canada
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2
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Sekine S, Mayama S, Nishijima N, Kojima T, Endo-Takahashi Y, Ishii Y, Shiono H, Akiyama S, Sakurai A, Sashida S, Hamano N, Tada R, Suzuki R, Maruyama K, Negishi Y. Development of a Gene and Nucleic Acid Delivery System for Skeletal Muscle Administration via Limb Perfusion Using Nanobubbles and Ultrasound. Pharmaceutics 2023; 15:1665. [PMID: 37376113 DOI: 10.3390/pharmaceutics15061665] [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: 04/27/2023] [Revised: 05/31/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
Strategies for gene and nucleic acid delivery to skeletal muscles have been extensively explored to treat Duchenne muscular dystrophy (DMD) and other neuromuscular diseases. Of these, effective intravascular delivery of naked plasmid DNA (pDNA) and nucleic acids into muscles is an attractive approach, given the high capillary density in close contact with myofibers. We developed lipid-based nanobubbles (NBs) using polyethylene-glycol-modified liposomes and an echo-contrast gas and found that these NBs could improve tissue permeability by ultrasound (US)-induced cavitation. Herein, we delivered naked pDNA or antisense phosphorodiamidate morpholino oligomers (PMOs) into the regional hindlimb muscle via limb perfusion using NBs and US exposure. pDNA encoding the luciferase gene was injected with NBs via limb perfusion into normal mice with application of US. High luciferase activity was achieved in a wide area of the limb muscle. DMD model mice were administered PMOs, designed to skip the mutated exon 23 of the dystrophin gene, with NBs via intravenous limb perfusion, followed by US exposure. The number of dystrophin-positive fibers increased in the muscles of mdx mice. Combining NBs and US exposure, which can be widely delivered to the hind limb muscles via the limb vein, could be an effective therapeutic approach for DMD and other neuromuscular disorders.
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Affiliation(s)
- Shohko Sekine
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Sayaka Mayama
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Nobuaki Nishijima
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Takuo Kojima
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Yoko Endo-Takahashi
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Yuko Ishii
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Hitomi Shiono
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Saki Akiyama
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Akane Sakurai
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Sanae Sashida
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Nobuhito Hamano
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Rui Tada
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
| | - Ryo Suzuki
- Laboratory of Drug and Gene Delivery Research, Faculty of Pharma-Sciences, Teikyo University, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8605, Japan
- Advanced Comprehensive Research Organization (ACRO), Teikyo University, Tokyo 173-8605, Japan
| | - Kazuo Maruyama
- Advanced Comprehensive Research Organization (ACRO), Teikyo University, Tokyo 173-8605, Japan
- Laboratory of Ultrasound Theranostics, Faculty of Pharma-Sciences, Teikyo University, Tokyo 173-8605, Japan
| | - Yoichi Negishi
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
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Wang J, Su W, Zhang T, Zhang S, Lei H, Ma F, Shi M, Shi W, Xie X, Di C. Aberrant Cyclin D1 splicing in cancer: from molecular mechanism to therapeutic modulation. Cell Death Dis 2023; 14:244. [PMID: 37024471 PMCID: PMC10079974 DOI: 10.1038/s41419-023-05763-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 03/15/2023] [Accepted: 03/21/2023] [Indexed: 04/08/2023]
Abstract
Cyclin D1 (CCND1), a crucial mediator of cell cycle progression, possesses many mutation types with different mutation frequencies in human cancers. The G870A mutation is the most common mutation in CCND1, which produces two isoforms: full-length CCND1a and divergent C-terminal CCND1b. The dysregulation of the CCND1 isoforms is associated with multiple human cancers. Exploring the molecular mechanism of CCND1 isoforms has offer new insight for cancer treatment. On this basis, the alterations of CCND1 gene are described, including amplification, overexpression, and mutation, especially the G870A mutation. Subsequently, we review the characteristics of CCND1 isoforms caused by G870A mutation. Additionally, we summarize cis-regulatory elements, trans-acting factors, and the splice mutation involved in splicing regulation of CCND1. Furthermore, we highlight the function of CCND1 isoforms in cell cycle, invasion, and metastasis in cancers. Importantly, the clinical role of CCND1 isoforms is also discussed, particularly concerning prognosis, chemotherapy, and radiotherapy. Last, emphasis is given to the corrective strategies that modulate the cancerous CCND1 isoforms. Thus, it is highlighting significance of aberrant isoforms of CCND1 as targets for cancer therapy.
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Affiliation(s)
- Jing Wang
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, China
- Bio-Medical Research Center, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Wei Su
- Bio-Medical Research Center, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, 730000, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 101408, China
| | - Taotao Zhang
- Bio-Medical Research Center, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, 730000, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 101408, China
| | - Shasha Zhang
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Huiwen Lei
- Bio-Medical Research Center, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000, China
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, 730000, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 101408, China
| | - Fengdie Ma
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Maoning Shi
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Wenjing Shi
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Xiaodong Xie
- School of Basic Medical Sciences, Lanzhou University, Lanzhou, 730000, China.
| | - Cuixia Di
- Bio-Medical Research Center, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, 730000, China.
- Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou, 730000, China.
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 101408, China.
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4
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Aartsma-Rus A, van Putten M, Mantuano P, De Luca A. On the use of D2.B10-Dmdmdx/J (D2.mdx) Versus C57BL/10ScSn-Dmdmdx/J (mdx) Mouse Models for Preclinical Studies on Duchenne Muscular Dystrophy: A Cautionary Note from Members of the TREAT-NMD Advisory Committee on Therapeutics. J Neuromuscul Dis 2023; 10:155-158. [PMID: 36336938 DOI: 10.3233/jnd-221547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The C57BL/10ScSn-Dmdmdx/J (mdx) mouse model has been used by researchers for decades as a model to study pathology of and develop therapies for Duchenne muscular dystrophy. However, the model is relatively mildly affected compared to the human situation. Recently, the D2.B10-Dmdmdx/J (D2.mdx) mouse model was suggested as a more severely affected and therefore better alternative. While the pathology of this model is indeed more pronounced early in life, it is not progressive, and increasing evidence suggest that it actually partially resolves with age. As such, caution is needed when using this model. However, as preclinical experts of the TREAT-NMD advisory committee for therapeutics (TACT), we frequently encounter study designs that underestimate this caveat. We here provide context for how to best use the two models for preclinical studies at the current stage of knowledge.
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Affiliation(s)
- Annemieke Aartsma-Rus
- 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
| | - Paola Mantuano
- Department of Pharmacy-Drug Sciences, Section of Pharmacology, University of Bari "Aldo Moro", Bari, Italy
| | - Annamaria De Luca
- Department of Pharmacy-Drug Sciences, Section of Pharmacology, University of Bari "Aldo Moro", Bari, Italy
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5
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Scripture-Adams DD, Chesmore KN, Barthélémy F, Wang RT, Nieves-Rodriguez S, Wang DW, Mokhonova EI, Douine ED, Wan J, Little I, Rabichow LN, Nelson SF, Miceli MC. Single nuclei transcriptomics of muscle reveals intra-muscular cell dynamics linked to dystrophin loss and rescue. Commun Biol 2022; 5:989. [PMID: 36123393 PMCID: PMC9485160 DOI: 10.1038/s42003-022-03938-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 09/01/2022] [Indexed: 02/05/2023] Open
Abstract
In Duchenne muscular dystrophy, dystrophin loss leads to chronic muscle damage, dysregulation of repair, fibro-fatty replacement, and weakness. We develop methodology to efficiently isolate individual nuclei from minute quantities of frozen skeletal muscle, allowing single nuclei sequencing of irreplaceable archival samples and from very small samples. We apply this method to identify cell and gene expression dynamics within human DMD and mdx mouse muscle, characterizing effects of dystrophin rescue by exon skipping therapy at single nuclei resolution. DMD exon 23 skipping events are directly observed and increased in myonuclei from treated mice. We describe partial rescue of type IIa and IIx myofibers, expansion of an MDSC-like myeloid population, recovery of repair/remodeling M2-macrophage, and repression of inflammatory POSTN1 + fibroblasts in response to exon skipping and partial dystrophin restoration. Use of this method enables exploration of cellular and transcriptomic mechanisms of dystrophin loss and repair within an intact muscle environment. Our initial findings will scaffold our future work to more directly examine muscular dystrophies and putative recovery pathways.
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Affiliation(s)
- Deirdre D Scripture-Adams
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine and College of Letters and Sciences, University of California, Los Angeles, Los Angeles, CA, USA
| | - Kevin N Chesmore
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Florian Barthélémy
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine and College of Letters and Sciences, University of California, Los Angeles, Los Angeles, CA, USA
| | - Richard T Wang
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Shirley Nieves-Rodriguez
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Derek W Wang
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Amgen, Thousand Oaks, CA, USA
| | - Ekaterina I Mokhonova
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Emilie D Douine
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Jijun Wan
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Isaiah Little
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine and College of Letters and Sciences, University of California, Los Angeles, Los Angeles, CA, USA
| | - Laura N Rabichow
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine and College of Letters and Sciences, University of California, Los Angeles, Los Angeles, CA, USA
| | - Stanley F Nelson
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA.
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
| | - M Carrie Miceli
- Center for Duchenne Muscular Dystrophy at UCLA, Los Angeles, CA, USA.
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine and College of Letters and Sciences, University of California, Los Angeles, Los Angeles, CA, USA.
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6
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Advanced Gene-Targeting Therapies for Motor Neuron Diseases and Muscular Dystrophies. Int J Mol Sci 2022; 23:ijms23094824. [PMID: 35563214 PMCID: PMC9101723 DOI: 10.3390/ijms23094824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/22/2022] [Accepted: 04/25/2022] [Indexed: 12/19/2022] Open
Abstract
Gene therapy is a revolutionary, cutting-edge approach to permanently ameliorate or amend many neuromuscular diseases by targeting their genetic origins. Motor neuron diseases and muscular dystrophies, whose genetic causes are well known, are the frontiers of this research revolution. Several genetic treatments, with diverse mechanisms of action and delivery methods, have been approved during the past decade and have demonstrated remarkable results. However, despite the high number of genetic treatments studied preclinically, those that have been advanced to clinical trials are significantly fewer. The most clinically advanced treatments include adeno-associated virus gene replacement therapy, antisense oligonucleotides, and RNA interference. This review provides a comprehensive overview of the advanced gene therapies for motor neuron diseases (i.e., amyotrophic lateral sclerosis and spinal muscular atrophy) and muscular dystrophies (i.e., Duchenne muscular dystrophy, limb-girdle muscular dystrophy, and myotonic dystrophy) tested in clinical trials. Emphasis has been placed on those methods that are a few steps away from their authoritative approval.
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7
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Rocha CT, Escolar DM. Treatment and Management of Muscular Dystrophies. Neuromuscul Disord 2022. [DOI: 10.1016/b978-0-323-71317-7.00020-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ohkubo A, Muto K, Watanabe R, Ogata D. Chemical Synthesis of Modified Oligonucleotides Containing 5'-Amino-5'-Deoxy-5'-Hydroxymethylthymidine Residues. Curr Protoc 2021; 1:e70. [PMID: 33657278 DOI: 10.1002/cpz1.70] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Introduction of cationic modifications into an oligonucleotide can increase its nuclease resistance and duplex- or triplex-forming abilities. In a recent study, we found that the nuclease resistance and RNA binding selectivity of an oligonucleotide containing a 5'-(R)-amino-5'-deoxy-5'-(R)-hydroxymethylthymidine residue were greater than those of the unmodified oligonucleotide. In this article, we describe the synthesis of 5'-amino-5'-deoxy-5'-hydroxymethylthymidine via dihydroxylation of the 5'-alkene derivative using either of two commercial AD (asymmetric dehydroxylation) mixes or via epoxidation and ring opening. We also provide detailed protocols for the syntheses of oligonucleotides containing 5'-amino-5'-deoxy-5'-hydroxymethylthymidine residues. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Synthesis of 5'-amino-5'-deoxy-5'-hydroxymethylthymidine phosphoramidites 9a and 9b Basic Protocol 2: Synthesis of oligonucleotides 1 and 2 containing 5'-amino-5'-deoxy-5'-hydoxymethylthymidine residues (R T and S T).
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Affiliation(s)
- Akihiro Ohkubo
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Kousuke Muto
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Rintaro Watanabe
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Daisuke Ogata
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
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Biscans A, Caiazzi J, McHugh N, Hariharan V, Muhuri M, Khvorova A. Docosanoic acid conjugation to siRNA enables functional and safe delivery to skeletal and cardiac muscles. Mol Ther 2021; 29:1382-1394. [PMID: 33348054 PMCID: PMC8058398 DOI: 10.1016/j.ymthe.2020.12.023] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 11/24/2020] [Accepted: 12/15/2020] [Indexed: 01/20/2023] Open
Abstract
Oligonucleotide therapeutics hold promise for the treatment of muscle- and heart-related diseases. However, oligonucleotide delivery across the continuous endothelium of muscle tissue is challenging. Here, we demonstrate that docosanoic acid (DCA) conjugation of small interfering RNAs (siRNAs) enables efficient (~5% of injected dose), sustainable (>1 month), and non-toxic (no cytokine induction at 100 mg/kg) gene silencing in both skeletal and cardiac muscles after systemic injection. When designed to target myostatin (muscle growth regulation gene), siRNAs induced ~55% silencing in various muscle tissues and 80% silencing in heart, translating into a ~50% increase in muscle volume within 1 week. Our study identifies compounds for RNAi-based modulation of gene expression in skeletal and cardiac muscles, paving the way for both functional genomics studies and therapeutic gene modulation in muscle and heart.
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Affiliation(s)
- Annabelle Biscans
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA; Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Jillian Caiazzi
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA; Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Nicholas McHugh
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA; Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Vignesh Hariharan
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA; Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Manish Muhuri
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01604, USA; Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01604, USA; VIDE Program, University of Massachusetts Medical School, Worcester, MA 01604, USA
| | - Anastasia Khvorova
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA; Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01604, USA.
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Novak JS, Spathis R, Dang UJ, Fiorillo AA, Hindupur R, Tully CB, Mázala DA, Canessa E, Brown KJ, Partridge TA, Hathout Y, Nagaraju K. Interrogation of Dystrophin and Dystroglycan Complex Protein Turnover After Exon Skipping Therapy. J Neuromuscul Dis 2021; 8:S383-S402. [PMID: 34569969 PMCID: PMC8673539 DOI: 10.3233/jnd-210696] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Recently, the Food and Drug Administration granted accelerated approvals for four exon skipping therapies -Eteplirsen, Golodirsen, Viltolarsen, and Casimersen -for Duchenne Muscular Dystrophy (DMD). However, these treatments have only demonstrated variable and largely sub-therapeutic levels of restored dystrophin protein in DMD patients, limiting their clinical impact. To better understand variable protein expression and the behavior of truncated dystrophin protein in vivo, we assessed turnover dynamics of restored dystrophin and dystrophin glycoprotein complex (DGC) proteins in mdx mice after exon skipping therapy, compared to those dynamics in wild type mice, using a targeted, highly-reproducible and sensitive, in vivo stable isotope labeling mass spectrometry approach in multiple muscle tissues. Through statistical modeling, we found that restored dystrophin protein exhibited altered stability and slower turnover in treated mdx muscle compared with that in wild type muscle (∼44 d vs. ∼24 d, respectively). Assessment of mRNA transcript stability (quantitative real-time PCR, droplet digital PCR) and dystrophin protein expression (capillary gel electrophoresis, immunofluorescence) support our dystrophin protein turnover measurements and modeling. Further, we assessed pathology-induced muscle fiber turnover through bromodeoxyuridine (BrdU) labeling to model dystrophin and DGC protein turnover in the context of persistent fiber degeneration. Our findings reveal sequestration of restored dystrophin protein after exon skipping therapy in mdx muscle leading to a significant extension of its half-life compared to the dynamics of full-length dystrophin in normal muscle. In contrast, DGC proteins show constant turnover attributable to myofiber degeneration and dysregulation of the extracellular matrix (ECM) in dystrophic muscle. Based on our results, we demonstrate the use of targeted mass spectrometry to evaluate the suitability and functionality of restored dystrophin isoforms in the context of disease and propose its use to optimize alternative gene correction strategies in development for DMD.
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Affiliation(s)
- James S. Novak
- Center for Genetic Medicine Research, Children’sResearch Institute, Children’s National Hospital, Washington, DC, USA
- Department of Genomics and PrecisionMedicine, The George Washington University School of Medicine and Health Sciences, Washington DC, USA
- Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington DC, USA
- Correspondence to: James Novak, 111 Michigan Avenue NW, Washington, DC, 20010-2916 USA. Tel.: +1 202 476 6135; E-mail: . and Kanneboyina Nagaraju, PO Box 6000, Binghamton, NY, 13902-6000 USA. Tel.: +1 607 777 5814; E-mail:
| | - Rita Spathis
- School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY USA
| | - Utkarsh J. Dang
- School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY USA
- Department of Health Sciences, Carleton University, Ottawa, Ontario, Canada
| | - Alyson A. Fiorillo
- Center for Genetic Medicine Research, Children’sResearch Institute, Children’s National Hospital, Washington, DC, USA
- Department of Genomics and PrecisionMedicine, The George Washington University School of Medicine and Health Sciences, Washington DC, USA
- Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington DC, USA
| | - Ravi Hindupur
- Center for Genetic Medicine Research, Children’sResearch Institute, Children’s National Hospital, Washington, DC, USA
| | - Christopher B. Tully
- Center for Genetic Medicine Research, Children’sResearch Institute, Children’s National Hospital, Washington, DC, USA
| | - Davi A.G. Mázala
- Center for Genetic Medicine Research, Children’sResearch Institute, Children’s National Hospital, Washington, DC, USA
- Department of Kinesiology, College of Health Professionals, Towson University, Towson, MD, USA
| | - Emily Canessa
- School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY USA
| | | | - Terence A. Partridge
- Center for Genetic Medicine Research, Children’sResearch Institute, Children’s National Hospital, Washington, DC, USA
| | - Yetrib Hathout
- School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY USA
| | - Kanneboyina Nagaraju
- Department of Genomics and PrecisionMedicine, The George Washington University School of Medicine and Health Sciences, Washington DC, USA
- School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY USA
- Correspondence to: James Novak, 111 Michigan Avenue NW, Washington, DC, 20010-2916 USA. Tel.: +1 202 476 6135; E-mail: . and Kanneboyina Nagaraju, PO Box 6000, Binghamton, NY, 13902-6000 USA. Tel.: +1 607 777 5814; E-mail:
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11
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Morpholino Oligomer-Induced Dystrophin Isoforms to Map the Functional Domains in the Dystrophin Protein. MOLECULAR THERAPY-NUCLEIC ACIDS 2020; 22:263-272. [PMID: 33230432 PMCID: PMC7516190 DOI: 10.1016/j.omtn.2020.08.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 08/18/2020] [Indexed: 12/21/2022]
Abstract
Dystrophin plays a crucial role in maintaining sarcolemma stability during muscle contractions, and mutations that prevent the expression of a functional protein cause Duchenne muscular dystrophy (DMD). Antisense oligonucleotide-mediated manipulation of pre-messenger RNA splicing to bypass Duchenne-causing mutations and restore functional dystrophin expression has entered the clinic for the most common DMD mutations. The rationale of "exon skipping" is based upon genotype-phenotype correlations observed in Becker muscular dystrophy, a milder allelic disorder generally characterized by in-frame deletions and internally truncated but semi-functional dystrophin isoforms. However, there is a lack of genotype-phenotype correlations downstream of DMD exon 55, as deletions in this region are rare and most single exon deletions would disrupt the reading frame. Consequently, the amenability of mutations in this region of the DMD gene to exon skipping strategies remains unknown. Here, we induced "Becker muscular dystrophy-like" in-frame dystrophin isoforms in vivo by intraperitoneal injection of peptide-conjugated phosphorodiamidate morpholino oligomers targeting selected exons. The dystrophin isoform encoded by the transcript lacking exons 56+57 appears to be more functional than that encoded by the 58+59-deleted transcript, as determined by higher dystrophin expression, stabilized β-dystroglycan, and less severe dystrophic pathology, indicating some potential for the strategy to address Duchenne-causing mutations affecting these exons.
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12
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Dzierlega K, Yokota T. Optimization of antisense-mediated exon skipping for Duchenne muscular dystrophy. Gene Ther 2020; 27:407-416. [DOI: 10.1038/s41434-020-0156-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 04/28/2020] [Accepted: 05/01/2020] [Indexed: 12/19/2022]
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13
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Raguraman P, Wang T, Ma L, Jørgensen PT, Wengel J, Veedu RN. Alpha-l-Locked Nucleic Acid-Modified Antisense Oligonucleotides Induce Efficient Splice Modulation In Vitro. Int J Mol Sci 2020; 21:ijms21072434. [PMID: 32244535 PMCID: PMC7177859 DOI: 10.3390/ijms21072434] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 03/27/2020] [Accepted: 03/29/2020] [Indexed: 01/04/2023] Open
Abstract
Alpha-l-Locked nucleic acid (α-l-LNA) is a stereoisomeric analogue of locked nucleic acid (LNA), which possesses excellent biophysical properties and also exhibits high target binding affinity to complementary oligonucleotide sequences and resistance to nuclease degradations. Therefore, α-l-LNA nucleotides could be utilised to develop stable antisense oligonucleotides (AO), which can be truncated without compromising the integrity and efficacy of the AO. In this study, we explored the potential of α-l-LNA nucleotides-modified antisense oligonucleotides to modulate splicing by inducing Dmd exon-23 skipping in mdx mouse myoblasts in vitro. For this purpose, we have synthesised and systematically evaluated the efficacy of α-l-LNA-modified 2'-O-methyl phosphorothioate (2'-OMePS) AOs of three different sizes including 20mer, 18mer and 16mer AOs in parallel to fully-modified 2'-OMePS control AOs. Our results demonstrated that the 18mer and 16mer truncated AO variants showed slightly better exon-skipping efficacy when compared with the fully-23 modified 2'-OMePS control AOs, in addition to showing low cytotoxicity. As there was no previous report on using α-l-LNA-modified AOs in splice modulation, we firmly believe that this initial study could be beneficial to further explore and expand the scope of α-l-LNA-modified AO therapeutic molecules.
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Affiliation(s)
- Prithi Raguraman
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth 6150 Australia; (P.R.); (T.W.)
- Perron Institute for Neurological and translational Science, Perth 6005, Australia
| | - Tao Wang
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth 6150 Australia; (P.R.); (T.W.)
- Perron Institute for Neurological and translational Science, Perth 6005, Australia
| | - Lixia Ma
- School of Statistics, Henan University of Economics and Law, Zhengzhou 450001, China;
| | - Per Trolle Jørgensen
- Nucleic Acid Center, Department of Physics and Chemistry and Pharmacy, University of Southern Denmark, M 5230 Odense, Denmark; (P.T.J.); (J.W.)
| | - Jesper Wengel
- Nucleic Acid Center, Department of Physics and Chemistry and Pharmacy, University of Southern Denmark, M 5230 Odense, Denmark; (P.T.J.); (J.W.)
| | - Rakesh N. Veedu
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth 6150 Australia; (P.R.); (T.W.)
- Perron Institute for Neurological and translational Science, Perth 6005, Australia
- Nucleic Acid Center, Department of Physics and Chemistry and Pharmacy, University of Southern Denmark, M 5230 Odense, Denmark; (P.T.J.); (J.W.)
- Correspondence:
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14
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Lu-Nguyen N, Ferry A, Schnell FJ, Hanson GJ, Popplewell L, Dickson G, Malerba A. Functional muscle recovery following dystrophin and myostatin exon splice modulation in aged mdx mice. Hum Mol Genet 2020; 28:3091-3100. [PMID: 31179493 DOI: 10.1093/hmg/ddz125] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/31/2019] [Accepted: 06/05/2019] [Indexed: 01/10/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a rare genetic disease affecting 1 in 3500-5000 newborn boys. It is due to mutations in the DMD gene with a consequent lack of dystrophin protein that leads to deterioration of myofibres and their replacement with fibro-adipogenic tissue. Out-of-frame mutations in the DMD gene can be modified by using antisense oligonucleotides (AONs) to promote skipping of specific exons such that the reading frame is restored and the resulting protein produced, though truncated, is functional. We have shown that AONs can also be used to knock down myostatin, a negative regulator of muscle growth and differentiation, through disruption of the transcript reading frame, and thereby enhance muscle strength. In young mdx mice, combined dystrophin and myostatin exon skipping therapy greatly improved DMD pathology, compared to the single dystrophin skipping approach. Here we show that in aged (>15-month-old) mdx mice, when the pathology is significantly more severe and more similar to the one observed in DMD patients, the effect of the combined therapy is slightly attenuated but still beneficial in improving the disease phenotype. These results confirm the beneficial outcome of the combination approach and support its translation into DMD clinical trials.
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Affiliation(s)
- Ngoc Lu-Nguyen
- Centres of Gene and Cell Therapy and Biomedical Sciences, School of Biological Sciences, Royal Holloway-University of London, Egham, Surrey, TW20 0EX, UK
| | - Arnaud Ferry
- Sorbonne Université UMRS974 INSERM, Institut de Myologie, 75013 Paris, France.,Université Sorbonne Paris Cité, 75006 Paris, France
| | | | - Gunnar J Hanson
- Sarepta Therapeutics, Inc., 215 First Street, Cambridge, MA 02142, USA
| | - Linda Popplewell
- Centres of Gene and Cell Therapy and Biomedical Sciences, School of Biological Sciences, Royal Holloway-University of London, Egham, Surrey, TW20 0EX, UK
| | - George Dickson
- Centres of Gene and Cell Therapy and Biomedical Sciences, School of Biological Sciences, Royal Holloway-University of London, Egham, Surrey, TW20 0EX, UK
| | - Alberto Malerba
- Centres of Gene and Cell Therapy and Biomedical Sciences, School of Biological Sciences, Royal Holloway-University of London, Egham, Surrey, TW20 0EX, UK
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15
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Ohkubo A, Muto K, Watanabe R, Nishizawa S, Hisamatsu S, Kanamori T. Chemical synthesis and properties of modified oligonucleotides containing 5'-amino-5'-deoxy-5'-hydroxymethylthymidine residues. Bioorg Med Chem 2020; 28:115407. [PMID: 32156498 DOI: 10.1016/j.bmc.2020.115407] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/26/2020] [Accepted: 02/27/2020] [Indexed: 12/13/2022]
Abstract
In this study, we designed 5'-amino-5'-deoxy-5'-hydroxymethylthymidine as a new oligonucleotide modification with an amino group directly attached to the 5'-carbon atom. We successfully synthesized two isomers of 5'-amino-5'-deoxy-5'-hydroxymethylthymidine via dihydroxylation of the 5'-vinyl group incorporated into 5'-deoxy-5'-C-methenylthymidine derivative. Moreover, it was found that the nuclease resistance, binding selectivity to single-stranded RNA, and triplex-forming ability of an oligonucleotide containing RT residues of the new compound were higher than those of the unmodified oligonucleotide.
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Affiliation(s)
- Akihiro Ohkubo
- Department of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midoriku, Yokohama 226-8501, Japan.
| | - Kousuke Muto
- Department of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midoriku, Yokohama 226-8501, Japan
| | - Rintaro Watanabe
- Department of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midoriku, Yokohama 226-8501, Japan
| | - Shuhei Nishizawa
- Department of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midoriku, Yokohama 226-8501, Japan
| | - Shugo Hisamatsu
- Department of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midoriku, Yokohama 226-8501, Japan
| | - Takashi Kanamori
- Department of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midoriku, Yokohama 226-8501, Japan
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16
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Systematic Approach to Developing Splice Modulating Antisense Oligonucleotides. Int J Mol Sci 2019; 20:ijms20205030. [PMID: 31614438 PMCID: PMC6834167 DOI: 10.3390/ijms20205030] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 10/08/2019] [Accepted: 10/10/2019] [Indexed: 01/05/2023] Open
Abstract
The process of pre-mRNA splicing is a common and fundamental step in the expression of most human genes. Alternative splicing, whereby different splice motifs and sites are recognised in a developmental and/or tissue-specific manner, contributes to genetic plasticity and diversity of gene expression. Redirecting pre-mRNA processing of various genes has now been validated as a viable clinical therapeutic strategy, providing treatments for Duchenne muscular dystrophy (inducing specific exon skipping) and spinal muscular atrophy (promoting exon retention). We have designed and evaluated over 5000 different antisense oligonucleotides to alter splicing of a variety of pre-mRNAs, from the longest known human pre-mRNA to shorter, exon-dense primary gene transcripts. Here, we present our guidelines for designing, evaluating and optimising splice switching antisense oligomers in vitro. These systematic approaches assess several critical factors such as the selection of target splicing motifs, choice of cells, various delivery reagents and crucial aspects of validating assays for the screening of antisense oligonucleotides composed of 2′-O-methyl modified bases on a phosphorothioate backbone.
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17
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Aung-Htut MT, McIntosh CS, West KA, Fletcher S, Wilton SD. In Vitro Validation of Phosphorodiamidate Morpholino Oligomers. Molecules 2019; 24:E2922. [PMID: 31408997 PMCID: PMC6719133 DOI: 10.3390/molecules24162922] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 08/08/2019] [Accepted: 08/08/2019] [Indexed: 01/14/2023] Open
Abstract
One of the crucial aspects of screening antisense oligonucleotides destined for therapeutic application is confidence that the antisense oligomer is delivered efficiently into cultured cells. Efficient delivery is particularly vital for antisense phosphorodiamidate morpholino oligomers, which have a neutral backbone, and are known to show poor gymnotic uptake. Here, we report several methods to deliver these oligomers into cultured cells. Although 4D-Nucleofector™ or Neon™ electroporation systems provide efficient delivery and use lower amounts of phosphorodiamidate morpholino oligomer, both systems are costly. We show that some readily available transfection reagents can be used to deliver phosphorodiamidate morpholino oligomers as efficiently as the electroporation systems. Among the transfection reagents tested, we recommend Lipofectamine 3000™ for delivering phosphorodiamidate morpholino oligomers into fibroblasts and Lipofectamine 3000™ or Lipofectamine 2000™ for myoblasts/myotubes. We also provide optimal programs for nucleofection into various cell lines using the P3 Primary Cell 4D-Nucleofector™ X Kit (Lonza), as well as antisense oligomers that redirect expression of ubiquitously expressed genes that may be used as positive treatments for human and murine cell transfections.
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Affiliation(s)
- May T Aung-Htut
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA 6150, Australia
- Perron Institute for Neurological and Translational Science, the University of Western Australia, Perth, WA 6009, Australia
| | - Craig S McIntosh
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA 6150, Australia.
- Perron Institute for Neurological and Translational Science, the University of Western Australia, Perth, WA 6009, Australia.
| | - Kristin A West
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA 6150, Australia
| | - Sue Fletcher
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA 6150, Australia
- Perron Institute for Neurological and Translational Science, the University of Western Australia, Perth, WA 6009, Australia
| | - Steve D Wilton
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA 6150, Australia
- Perron Institute for Neurological and Translational Science, the University of Western Australia, Perth, WA 6009, Australia
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18
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Wells DJ. What is the level of dystrophin expression required for effective therapy of Duchenne muscular dystrophy? J Muscle Res Cell Motil 2019; 40:141-150. [PMID: 31289969 DOI: 10.1007/s10974-019-09535-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 06/27/2019] [Indexed: 12/21/2022]
Abstract
Duchenne muscular dystrophy (DMD) is a fatal X-linked muscle wasting disease. The disease is due to mutations in the DMD gene that encodes for a large intracellular protein called dystrophin. Dystrophin plays a critical role in linking the internal cytoskeleton of the striated muscle cell with the extracellular matrix as well as having cell signalling functions. In its absence muscle contraction is associated with cycles of damage, repair, inflammation and fibrosis with eventual loss of muscle and replacement with fat. Experiments in animal models of DMD have generated a number of different approaches to the induction of dystrophin including viral vector mediated delivery of a recombinant dystrophin gene, antisense oligonucleotide mediated exon-skipping to restore the open reading frame in the dystrophin mRNA, read-through of premature stop mutations, genome modification using CRISPR-Cas9 or cell based transfer of a functional dystrophin gene. In all cases, it will be important to understand how much dystrophin expression is required for a clinically effective therapy and this review examines the data from humans and animal models to estimate the percentage of endogenous dystrophin that is likely to have significant clinical benefit. While there are a number of important caveats to consider, including the appropriate outcome measures, this review suggests that approximately 20% of endogenous levels uniformly distributed within the skeletal muscles and the heart may be sufficient to largely prevent disease progression.
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Affiliation(s)
- Dominic J Wells
- Neuromuscular Diseases Group, Department of Comparative Biomedical Sciences, Royal Veterinary College, Royal College Street, London, NW1 0TU, UK.
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19
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Tsoumpra MK, Fukumoto S, Matsumoto T, Takeda S, Wood MJA, Aoki Y. Peptide-conjugate antisense based splice-correction for Duchenne muscular dystrophy and other neuromuscular diseases. EBioMedicine 2019; 45:630-645. [PMID: 31257147 PMCID: PMC6642283 DOI: 10.1016/j.ebiom.2019.06.036] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 05/31/2019] [Accepted: 06/18/2019] [Indexed: 12/14/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is an X-linked disorder characterized by progressive muscle degeneration, caused by the absence of dystrophin. Exon skipping by antisense oligonucleotides (ASOs) has recently gained recognition as therapeutic approach in DMD. Conjugation of a peptide to the phosphorodiamidate morpholino backbone (PMO) of ASOs generated the peptide-conjugated PMOs (PPMOs) that exhibit a dramatically improved pharmacokinetic profile. When tested in animal models, PPMOs demonstrate effective exon skipping in target muscles and prolonged duration of dystrophin restoration after a treatment regime. Herein we summarize the main pathophysiological features of DMD and the emergence of PPMOs as promising exon skipping agents aiming to rescue defective gene expression in DMD and other neuromuscular diseases. The listed PPMO laboratory findings correspond to latest trends in the field and highlight the obstacles that must be overcome prior to translating the animal-based research into clinical trials tailored to the needs of patients suffering from neuromuscular diseases.
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Key Words
- aso, antisense oligonucleotides
- cns, central nervous system
- cpp, cell penetrating peptide
- dgc, dystrophin glyco-protein complex
- dmd, duchenne muscular dystrophy
- fda, us food and drug administration
- pmo, phosphorodiamidate morpholino
- ppmo, peptide-conjugated pmos
- ps, phosphorothioate
- sma, spinal muscular atrophy
- 2ʹ-ome, 2ʹ-o-methyl
- 2ʹ-moe, 2ʹ-o-methoxyethyl
- 6mwt, 6-minute walk test
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Affiliation(s)
- Maria K Tsoumpra
- Department of Molecular Therapy, National Institute of Neuroscience, National Centre of Neurology and Psychiatry, Kodaira-shi, Tokyo, Japan
| | - Seiji Fukumoto
- Fujii Memorial Institute of Medical Sciences, University of Tokushima, Tokushima, Japan
| | - Toshio Matsumoto
- Fujii Memorial Institute of Medical Sciences, University of Tokushima, Tokushima, Japan
| | - Shin'ichi Takeda
- Department of Molecular Therapy, National Institute of Neuroscience, National Centre of Neurology and Psychiatry, Kodaira-shi, Tokyo, Japan
| | | | - Yoshitsugu Aoki
- Department of Molecular Therapy, National Institute of Neuroscience, National Centre of Neurology and Psychiatry, Kodaira-shi, Tokyo, Japan.
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20
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Golshirazi G, Ciszewski L, Lu-Nguyen N, Popplewell L. Antisense Oligonucleotide Targeting of 3'-UTR of mRNA for Expression Knockdown. Methods Mol Biol 2019; 1828:91-124. [PMID: 30171537 DOI: 10.1007/978-1-4939-8651-4_6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
With the recent conditional approval of an antisense oligonucleotide (AON) that restores the reading frame of DMD transcript in a subset of Duchenne muscular dystrophy patients, it has been established that AONs sharing similar chemistry have clear clinical potential. Genetic diseases, such as facioscapulohumeral dystrophy (FSHD), can be the result of gain-of-function mutations. Since mRNA processing in terms of termination of transcription, its transport from the nucleus to the cytoplasm, its stability and translation efficiency are dependent on key 3'UTR elements, it follows that targeting these elements with AONs have the potential to induce gene silencing. Aberrant expression of the Double homeobox 4 (DUX4) transcription factor and the downstream consequences of such expression is the hallmark of FSHD. Here we describe the bioinformatic strategies behind the design of AONs targeting polyadenylation signals and the methodologies relevant to their in vitro screening for efficacy and safety, including analysis of expression at the transcript and protein level of the specific target and downstream genes, and measurement of the effect on the fusion index of myotubes. The targeting of permissive DUX4 and MSTN are used as examples. MSTN encodes for myostatin, a negative regulator of myogenesis; the downregulation of MSTN expression has the potential to address the muscular atrophy associated with muscular dystrophies, sarcopenia, cancer and acquired immunodeficiency syndrome.
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Affiliation(s)
- Golnoush Golshirazi
- Centre of Biomedical Sciences, School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, UK
| | - Lukasz Ciszewski
- Centre of Biomedical Sciences, School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, UK
| | - Ngoc Lu-Nguyen
- Centre of Biomedical Sciences, School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, UK
| | - Linda Popplewell
- Centre of Biomedical Sciences, School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, UK.
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21
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van Putten M, Tanganyika-de Winter C, Bosgra S, Aartsma-Rus A. Nonclinical Exon Skipping Studies with 2'-O-Methyl Phosphorothioate Antisense Oligonucleotides in mdx and mdx-utrn-/- Mice Inspired by Clinical Trial Results. Nucleic Acid Ther 2019; 29:92-103. [PMID: 30672725 PMCID: PMC6461150 DOI: 10.1089/nat.2018.0759] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Duchenne muscular dystrophy is a severe, progressive muscle-wasting disease that is caused by mutations that abolish the production of functional dystrophin protein. The exon skipping approach aims to restore the disrupted dystrophin reading frame, to allow the production of partially functional dystrophins, such as found in the less severe Becker muscular dystrophy. Exon skipping is achieved by antisense oligonucleotides (AONs). Several chemical modifications have been tested in nonclinical and clinical trials. The morpholino phosphorodiamidate oligomer eteplirsen has been approved by the Food and Drug Administration, whereas clinical development with the 2'-O-methyl phosphorothioate (2OMePS) AON drisapersen was recently stopped. In this study, we aimed to study various aspects of 2OMePS AONs in nonclinical animal studies. We show that while efficiency of exon skipping restoration is comparable in young and older C57BL/10ScSn-Dmdmdx/J (mdx/BL10) mice, functional improvement was only observed for younger treated mice. Muscle quality did not affect exon skipping efficiency as exon skip and dystrophin levels were similar between mdx/BL10 and more severely affected, age-matched D2-mdx mice. We further report that treadmill running increases AON uptake and dystrophin levels in mdx/BL10 mice. Finally, we show that even low levels of exon skipping and dystrophin restoration are sufficient to significantly increase the survival of mdx-utrn-/- mice from 70 to 97 days.
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Affiliation(s)
- Maaike van Putten
- 1 Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | | | - Sieto Bosgra
- 2 Biomarin Nederland BV, Leiden, the Netherlands
| | - Annemieke Aartsma-Rus
- 1 Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
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22
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Lim KRQ, Echigoya Y, Nagata T, Kuraoka M, Kobayashi M, Aoki Y, Partridge T, Maruyama R, Takeda S, Yokota T. Efficacy of Multi-exon Skipping Treatment in Duchenne Muscular Dystrophy Dog Model Neonates. Mol Ther 2018; 27:76-86. [PMID: 30448197 DOI: 10.1016/j.ymthe.2018.10.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 10/14/2018] [Accepted: 10/16/2018] [Indexed: 12/12/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is caused by mutations in DMD, which codes for dystrophin. Because the progressive and irreversible degeneration of muscle occurs from childhood, earlier therapy is required to prevent dystrophic progression. Exon skipping by antisense oligonucleotides called phosphorodiamidate morpholino oligomers (PMOs), which restores the DMD reading frame and dystrophin expression, is a promising candidate for use in neonatal patients, yet the potential remains unclear. Here, we investigate the systemic efficacy and safety of early exon skipping in dystrophic dog neonates. Intravenous treatment of canine X-linked muscular dystrophy in Japan dogs with a 4-PMO cocktail resulted in ∼3%-27% in-frame exon 6-9 skipping and dystrophin restoration across skeletal muscles up to 14% of healthy levels. Histopathology was ameliorated with the reduction of fibrosis and/or necrosis area and centrally nucleated fibers, significantly in the diaphragm. Treatment induced cardiac multi-exon skipping, though dystrophin rescue was not detected. Functionally, treatment led to significant improvement in the standing test. Toxicity was not observed from blood tests. This is the first study to demonstrate successful multi-exon skipping treatment and significant functional improvement in dystrophic dogs. Early treatment was most beneficial for respiratory muscles, with implications for addressing pulmonary malfunction in patients.
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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
| | - Yusuke Echigoya
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2H7, Canada; Laboratory of Biomedical Science, Department of Veterinary Medicine, Nihon University, Fujisawa, Kanagawa 252-0880, Japan
| | - Tetsuya Nagata
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8502, Japan
| | - Mutsuki Kuraoka
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8502, Japan
| | - Masanori Kobayashi
- Department of Reproduction, Nippon Veterinary and Life Science University, Musashino, Tokyo 180-0023, Japan
| | - Yoshitsugu Aoki
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8502, Japan
| | - Terence Partridge
- Research Center for Genetic Medicine, Children's National Medical Center, Washington, DC 20010, USA; Department of Integrative Systems Biology, George Washington University School of Medicine, Washington, DC 20010, USA
| | - Rika Maruyama
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2H7, Canada
| | - Shin'ichi Takeda
- Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo 187-8502, Japan.
| | - Toshifumi Yokota
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G2H7, Canada; Muscular Dystrophy Canada Research Chair, Edmonton, AB T6G2H7, Canada.
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23
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Han G, Lin C, Ning H, Gao X, Yin H. Long-Term Morpholino Oligomers in Hexose Elicits Long-Lasting Therapeutic Improvements in mdx Mice. MOLECULAR THERAPY-NUCLEIC ACIDS 2018; 12:478-489. [PMID: 30195785 PMCID: PMC6070676 DOI: 10.1016/j.omtn.2018.06.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 06/11/2018] [Accepted: 06/14/2018] [Indexed: 12/24/2022]
Abstract
Approval of antisense oligonucleotide eteplirsen highlights the promise of exon-skipping therapeutics for Duchenne muscular dystrophy patients. However, the limited efficacy of eteplirsen underscores the importance to improve systemic delivery and efficacy. Recently, we demonstrated that a glucose and fructose (GF) delivery formulation effectively potentiates phosphorodiamidate morpholino oligomer (PMO). Considering the clinical potential of GF, it is important to determine the long-term compatibility and efficacy with PMO in mdx mice prior to clinical translation. Here, we report that yearlong administration of a clinically applicable PMO dose (50 mg/kg/week for 3 weeks followed by 50 mg/kg/month for 11 months) with GF elicited sustainably high levels of dystrophin expression in mdx mice, with up to 45% of the normal level of dystrophin restored in most peripheral muscles without any detectable toxicity. Importantly, PMO-GF resulted in phenotypical rescue and mitochondrial biogenesis with functional improvement. Carbohydrate metabolites measurements revealed improved metabolic and energetic conditions after PMO-GF treatment in mdx mice without metabolic anomaly. Collectively, our study shows PMO-GF’s ability to elicit long-lasting therapeutic effects with tolerable toxicity and represents a new treatment modality for Duchenne muscular dystrophy, and provides guidelines for antisense oligonucleotides with GF in clinical use.
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Affiliation(s)
- Gang Han
- School of Medical Laboratory and Department of Cell Biology, Tianjin Medical University, Qixiangtai Road, Heping District, Tianjin 300070, China
| | - Caorui Lin
- School of Medical Laboratory and Department of Cell Biology, Tianjin Medical University, Qixiangtai Road, Heping District, Tianjin 300070, China
| | - Hanhan Ning
- School of Medical Laboratory and Department of Cell Biology, Tianjin Medical University, Qixiangtai Road, Heping District, Tianjin 300070, China
| | - Xianjun Gao
- School of Medical Laboratory and Department of Cell Biology, Tianjin Medical University, Qixiangtai Road, Heping District, Tianjin 300070, China
| | - HaiFang Yin
- School of Medical Laboratory and Department of Cell Biology, Tianjin Medical University, Qixiangtai Road, Heping District, Tianjin 300070, China.
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24
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PMO Delivery System Using Bubble Liposomes and Ultrasound Exposure for Duchenne Muscular Dystrophy Treatment. Methods Mol Biol 2018; 1687:185-192. [PMID: 29067664 DOI: 10.1007/978-1-4939-7374-3_13] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Duchenne muscular dystrophy (DMD) is a genetic disorder characterized by progressive muscle degeneration, caused by nonsense or frameshift mutations in the dystrophin (DMD) gene. Antisense oligonucleotides can be used to induce specific exon skipping; recently, a phosphorodiamidate morpholino oligomer (PMO) has been approved for clinical use in DMD. However, an efficient PMO delivery strategy is required to improve the therapeutic efficacy in DMD patients. We previously developed polyethylene glycol (PEG)-modified liposomes containing ultrasound contrast gas, "Bubble liposomes" (BLs), and found that the combination of BLs with ultrasound exposure is a useful gene delivery tool. Here, we describe an efficient PMO delivery strategy using the combination of BLs and ultrasound exposure to treat muscles in a DMD mouse model (mdx). This ultrasound-mediated BL technique can increase the PMO-mediated exon-skipping efficiency, leading to significantly increased dystrophin expression. Thus, the combination of BLs and ultrasound exposure may be a feasible PMO delivery method to improve therapeutic efficacy and reduce the PMO dosage for DMD treatment.
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25
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Viola HM, Johnstone VP, Adams AM, Fletcher S, Hool LC. A Morpholino Oligomer Therapy Regime That Restores Mitochondrial Function and Prevents mdx Cardiomyopathy. JACC Basic Transl Sci 2018; 3:391-402. [PMID: 30062225 PMCID: PMC6059013 DOI: 10.1016/j.jacbts.2018.03.007] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 03/15/2018] [Indexed: 02/07/2023]
Abstract
Current clinical trials demonstrate Duchenne muscular dystrophy (DMD) patients receiving phosphorodiamidate morpholino oligomer (PMO) therapy exhibit improved ambulation and stable pulmonary function; however, cardiac abnormalities remain. Utilizing the same PMO chemistry as current clinical trials, we have identified a non-toxic PMO treatment regimen that restores metabolic activity and prevents DMD cardiomyopathy. We propose that a treatment regimen of this nature may have the potential to significantly improve morbidity and mortality from DMD by improving ambulation, stabilizing pulmonary function, and preventing the development of cardiomyopathy.
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Key Words
- DMD, Duchenne muscular dystrophy
- ICa-L, L-type Ca2+ channel
- JC-1, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide
- L-type calcium channels
- PMO, phosphorodiamidate morpholino oligomer
- RT-PCR, reverse transcriptase polymerase chain reaction
- cardiomyopathy
- mdx, murine model of Duchenne muscular dystrophy
- mitochondria
- wt, wild type
- Ψm, mitochondrial membrane potential
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Affiliation(s)
- Helena M. Viola
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Victoria P.A. Johnstone
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Abbie M. Adams
- Centre for Comparative Genomics, Murdoch University, Murdoch, Western Australia, Australia
| | - Susan Fletcher
- Centre for Comparative Genomics, Murdoch University, Murdoch, Western Australia, Australia
- Perron Institute for Neuroscience and Translational Science, and Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, Western Australia, Australia
| | - Livia C. Hool
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
- Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
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26
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Boutilier J, Moulton HM. Surface Plasmon Resonance-Based Concentration Determination Assay: Label-Free and Antibody-Free Quantification of Morpholinos. Methods Mol Biol 2018; 1565:251-263. [PMID: 28364249 DOI: 10.1007/978-1-4939-6817-6_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Surface plasmon resonance (SPR) is a physical process that allows label-free and real-time detection of biomolecular interactions. SPR provides a rapid and quantitative method for studying interactions of macromolecules such as proteins and nucleic acids. Antisense Morpholino oligomers are widely used to regulate gene expression and the US FDA has approved a Morpholino drug for treatment of Duchenne muscular dystrophy. Here, we describe an antibody-free, label-free, high-throughput, and walk-away SPR method for quantification of Morpholino compounds extracted from biological specimens. This provides a valuable way for determining pharmacokinetics and pharmacodynamics of Morpholino oligomers in biological matrices for research and therapeutic applications.
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Affiliation(s)
- Jordan Boutilier
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, 105 Magruder Hall, Corvallis, OR, 97331, USA
| | - Hong M Moulton
- Department of Biomedical Sciences, College of Veterinary Medicine, Oregon State University, 105 Magruder Hall, Corvallis, OR, 97331, USA.
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27
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Wang DW, Mokhonova EI, Kendall GC, Becerra D, Naeini YB, Cantor RM, Spencer MJ, Nelson SF, Miceli MC. Repurposing Dantrolene for Long-Term Combination Therapy to Potentiate Antisense-Mediated DMD Exon Skipping in the mdx Mouse. MOLECULAR THERAPY. NUCLEIC ACIDS 2018; 11:180-191. [PMID: 29858053 PMCID: PMC5992346 DOI: 10.1016/j.omtn.2018.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Revised: 02/05/2018] [Accepted: 02/06/2018] [Indexed: 01/16/2023]
Abstract
Duchenne muscular dystrophy (DMD) is caused by mutations in DMD, resulting in loss of dystrophin, which is essential to muscle health. DMD “exon skipping” uses anti-sense oligo-nucleotides (AONs) to force specific exon exclusion during mRNA processing to restore reading frame and rescue of partially functional dystrophin protein. Although exon-skipping drugs in humans show promise, levels of rescued dystrophin protein remain suboptimal. We previously identified dantrolene as a skip booster when combined with AON in human DMD cultures and short-term mdx dystrophic mouse studies. Here, we assess the effect of dantrolene/AON combination on DMD exon-23 skipping over long-term mdx treatment under conditions that better approximate potential human dosing. To evaluate the dantrolene/AON combination treatment effect on dystrophin induction, we assayed three AON doses, with and without oral dantrolene, to assess multiple outcomes across different muscles. Meta-analyses of the results of statistical tests from both the quadriceps and diaphragm assessing contributions of dantrolene beyond AON, across all AON treatment groups, provide strong evidence that dantrolene modestly boosts exon skipping and dystrophin rescue while reducing muscle pathology in mdx mice (p < 0.0087). These findings support a trial of combination dantrolene/AON to increase exon-skipping efficacy and highlight the value of combinatorial approaches and Food and Drug Administration (FDA) drug re-purposing for discovery of unsuspected therapeutic application and rapid translation.
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Affiliation(s)
- Derek W Wang
- Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, Los Angeles, CA, USA; Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine and College of Letters and Sciences, University of California, Los Angeles, Los Angeles, CA, USA
| | - Ekaterina I Mokhonova
- Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, Los Angeles, CA, USA; Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine and College of Letters and Sciences, University of California, Los Angeles, Los Angeles, CA, USA; Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Genevieve C Kendall
- Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, Los Angeles, CA, USA; Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Diana Becerra
- Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, Los Angeles, CA, USA; Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Yalda B Naeini
- Department of Pathology and Laboratory Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Rita M Cantor
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Melissa J Spencer
- Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, Los Angeles, CA, USA; Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Stanley F Nelson
- Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, Los Angeles, CA, USA; Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA; Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, USA; Department of Pathology and Laboratory Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - M Carrie Miceli
- Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, Los Angeles, CA, USA; Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine and College of Letters and Sciences, University of California, Los Angeles, Los Angeles, CA, USA; Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, USA.
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28
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Abstract
Since its discovery in 1977, much has been known about RNA splicing and how it plays a central role in human development, function, and, notably, disease. Defects in RNA splicing account for at least 10% of all genetic disorders, with the number expected to increase as more information is uncovered on the contribution of noncoding genomic regions to disease. Splice modulation through the use of antisense oligonucleotides (AOs) has emerged as a promising avenue for the treatment of these disorders. In fact, two splice-switching AOs have recently obtained approval from the US Food and Drug Administration: eteplirsen (Exondys 51) for Duchenne muscular dystrophy, and nusinersen (Spinraza) for spinal muscular atrophy. These work by exon skipping and exon inclusion, respectively. In this chapter, we discuss the early development of AO-based splice modulation therapy-its invention, first applications, and its evolution into the approach we are now familiar with. We give a more extensive history of exon skipping in particular, as it is the splice modulation approach given the most focus in this book.
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Affiliation(s)
- Kenji Rowel Q Lim
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Toshifumi Yokota
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada.
- The Friends of Garrett Cumming Research and Muscular Dystrophy Canada HM Toupin Neurological Science Research Chair, Edmonton, AB, Canada.
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29
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Takahashi Y, Araie Y, Nomura D, Takahashi Y, Sano K, Saji H, Takakura Y, Nishikawa M. Construction of nanostructured DNA harbouring phosphorodiamidate morpholino oligonucleotide for controlled tissue distribution in mice. J Drug Target 2017; 26:373-381. [PMID: 28972806 DOI: 10.1080/1061186x.2017.1387789] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Phosphorodiamidate morpholino oligonucleotides (PMOs) are a class of antisense oligonucleotides used in the treatment of neuromuscular diseases. Their major drawbacks are high blood clearance and poor cellular delivery. Previously, we demonstrated that tripod-like nanostructured DNA, or tripodna, was efficiently taken up by macrophages and dendritic cells. In this study, we used iodine-125(125I)-labelled PMOs, designed a tripodna harbouring an 125I-PMO (125I-PMO/tripodna), and evaluated whether this tripodna could control the pharmacokinetic properties of PMO. Gel electrophoresis showed that 125I-PMO was almost completely incorporated into the tripodna. Compared to 125I-PMO, 125I-PMO/tripodna was more efficiently taken up by macrophage-like RAW264.7 cells. Moreover, after intravenous injection into mice, the area under the plasma concentration-time curve of 125I-PMO/tripodna was significantly larger than that of 125I-PMO. The distribution of 125I-PMO/tripodna in the liver and spleen at 24 h was 32- and 51-fold higher than that of 125I-PMO, respectively. The fractionation of liver cells revealed that non-parenchymal cells were the major cells contributing to the hepatic uptake of 125I-PMO/tripodna. These results indicate that tripodna has the potential to deliver PMO, particularly to the liver and spleen.
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Affiliation(s)
- Yosuke Takahashi
- a Department of Biopharmaceutics and Drug Metabolism, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto , Japan
| | - Yuki Araie
- a Department of Biopharmaceutics and Drug Metabolism, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto , Japan
| | - Daiki Nomura
- a Department of Biopharmaceutics and Drug Metabolism, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto , Japan
| | - Yuki Takahashi
- a Department of Biopharmaceutics and Drug Metabolism, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto , Japan
| | - Kohei Sano
- b Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto , Japan
| | - Hideo Saji
- b Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto , Japan
| | - Yoshinobu Takakura
- a Department of Biopharmaceutics and Drug Metabolism, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto , Japan
| | - Makiya Nishikawa
- a Department of Biopharmaceutics and Drug Metabolism, Graduate School of Pharmaceutical Sciences , Kyoto University , Kyoto , Japan.,c Faculty of Pharmaceutical Sciences, Laboratory of Biopharmaceutics , Tokyo University of Science , Noda, Chiba , Japan
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30
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Novak JS, Hogarth MW, Boehler JF, Nearing M, Vila MC, Heredia R, Fiorillo AA, Zhang A, Hathout Y, Hoffman EP, Jaiswal JK, Nagaraju K, Cirak S, Partridge TA. Myoblasts and macrophages are required for therapeutic morpholino antisense oligonucleotide delivery to dystrophic muscle. Nat Commun 2017; 8:941. [PMID: 29038471 PMCID: PMC5643396 DOI: 10.1038/s41467-017-00924-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 08/07/2017] [Indexed: 01/15/2023] Open
Abstract
Exon skipping is a promising therapeutic strategy for Duchenne muscular dystrophy (DMD), employing morpholino antisense oligonucleotides (PMO-AO) to exclude disruptive exons from the mutant DMD transcript and elicit production of truncated dystrophin protein. Clinical trials for PMO show variable and sporadic dystrophin rescue. Here, we show that robust PMO uptake and efficient production of dystrophin following PMO administration coincide with areas of myofiber regeneration and inflammation. PMO localization is sustained in inflammatory foci where it enters macrophages, actively differentiating myoblasts and newly forming myotubes. We conclude that efficient PMO delivery into muscle requires two concomitant events: first, accumulation and retention of PMO within inflammatory foci associated with dystrophic lesions, and second, fusion of PMO-loaded myoblasts into repairing myofibers. Identification of these factors accounts for the variability in clinical trials and suggests strategies to improve this therapeutic approach to DMD.Exon skipping is a strategy for the treatment of Duchenne muscular dystrophy, but has variable efficacy. Here, the authors show that dystrophin restoration occurs preferentially in areas of myofiber regeneration, where antisense oligonucleotides are stored in macrophages and delivered to myoblasts and newly formed myotubes.
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Affiliation(s)
- James S Novak
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA.,Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA
| | - Marshall W Hogarth
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA
| | - Jessica F Boehler
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA
| | - Marie Nearing
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA
| | - Maria C Vila
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA
| | - Raul Heredia
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA
| | - Alyson A Fiorillo
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA.,Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA
| | - Aiping Zhang
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA
| | - Yetrib Hathout
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA.,Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA.,Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY, 13902, USA
| | - Eric P Hoffman
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA.,Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA.,Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY, 13902, USA
| | - Jyoti K Jaiswal
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA.,Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA
| | - Kanneboyina Nagaraju
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA.,Institute for Biomedical Sciences, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA.,Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA.,Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY, 13902, USA
| | - Sebahattin Cirak
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA.,Institute for Human Genetics, University Hospital Cologne, Cologne, 50923, Germany.,Department of Pediatrics, University Hospital Cologne, Cologne, 50923, Germany.,Center for Molecular Medicine, University of Cologne, Cologne, 50931, Germany
| | - Terence A Partridge
- Center for Genetic Medicine Research, Children's Research Institute, Children's National Health System, Washington, DC, 20010, USA. .,Institute for Biomedical Sciences, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA. .,Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC, 20052, USA.
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31
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Abstract
Exondys 51 is the first therapy for Duchenne muscular dystrophy (DMD) to have been granted accelerated approval by the FDA. Approval was granted based on using dystrophin expression as a surrogate marker. Exondys 51 targets DMD exon 51 for skipping to restore the reading frame for 13% of Duchenne patients.
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Affiliation(s)
- Courtney S Young
- Molecular Biology Interdepartmental Program, Center for Duchenne Muscular Dystrophy, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA 90095
| | - April D Pyle
- Molecular Biology Interdepartmental Program, Center for Duchenne Muscular Dystrophy, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA 90095; Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095.
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32
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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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33
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Fletcher S, Bellgard MI, Price L, Akkari AP, Wilton SD. Translational development of splice-modifying antisense oligomers. Expert Opin Biol Ther 2016; 17:15-30. [PMID: 27805416 DOI: 10.1080/14712598.2017.1250880] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Antisense nucleic acid analogues can interact with pre-mRNA motifs and influence exon or splice site selection and thereby alter gene expression. Design of antisense molecules to target specific motifs can result in either exon exclusion or exon inclusion during splicing. Novel drugs exploiting the antisense concept are targeting rare, life-limiting diseases; however, the potential exists to treat a wide range of conditions by antisense-mediated splice intervention. Areas covered: In this review, the authors discuss the clinical translation of novel molecular therapeutics to address the fatal neuromuscular disorders Duchenne muscular dystrophy and spinal muscular atrophy. The review also highlights difficulties posed by issues pertaining to restricted participant numbers, variable phenotype and disease progression, and the identification and validation of study endpoints. Expert opinion: Translation of novel therapeutics for Duchenne muscular dystrophy and spinal muscular atrophy has been greatly advanced by multidisciplinary research, academic-industry partnerships and in particular, the engagement and support of the patient community. Sponsors, supporters and regulators are cooperating to deliver new drugs and identify and define meaningful outcome measures. Non-conventional and adaptive trial design could be particularly suited to clinical evaluation of novel therapeutics and strategies to treat serious, rare diseases that may be problematic to study using more conventional clinical trial structures.
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Affiliation(s)
- S Fletcher
- a Centre for Neuromuscular and Neurological Disorders , University of Western Australia , Nedlands , Western Australia , Australia.,b Western Australian Neuroscience Research Institute , Nedlands , Western Australia , Australia.,c Centre for Comparative Genomics , Murdoch University , Western Australia , Australia
| | - M I Bellgard
- b Western Australian Neuroscience Research Institute , Nedlands , Western Australia , Australia.,c Centre for Comparative Genomics , Murdoch University , Western Australia , Australia
| | - L Price
- a Centre for Neuromuscular and Neurological Disorders , University of Western Australia , Nedlands , Western Australia , Australia.,b Western Australian Neuroscience Research Institute , Nedlands , Western Australia , Australia.,c Centre for Comparative Genomics , Murdoch University , Western Australia , Australia
| | - A P Akkari
- b Western Australian Neuroscience Research Institute , Nedlands , Western Australia , Australia.,c Centre for Comparative Genomics , Murdoch University , Western Australia , Australia.,d Shiraz Pharmaceuticals, Inc , Chapel Hill , NC , USA
| | - S D Wilton
- a Centre for Neuromuscular and Neurological Disorders , University of Western Australia , Nedlands , Western Australia , Australia.,b Western Australian Neuroscience Research Institute , Nedlands , Western Australia , Australia.,c Centre for Comparative Genomics , Murdoch University , Western Australia , Australia
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34
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Radan L, Hughes CS, Teichroeb JH, Postovit LM, Betts DH. Delivering Antisense Morpholino Oligonucleotides to Target Telomerase Splice Variants in Human Embryonic Stem Cells. Methods Mol Biol 2016; 1341:133-42. [PMID: 25822725 DOI: 10.1007/7651_2015_226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Morpholino oligonucleotides (MO) are an innovative tool that provides a means for examining and modifying gene expression outcomes by antisense interaction with targeted RNA transcripts. The site-specific nature of their binding facilitates focused modulation to alter splice variant expression patterns. Here we describe the steric-blocking of human telomerase reverse transcriptase (hTERT) Δα and Δβ splice variants using MO to examine cellular outcomes related to pluripotency and differentiation in human embryonic stem cells.
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Affiliation(s)
- Lida Radan
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada
| | - Chris S Hughes
- British Columbia Cancer Research Center, Vancouver, BC, Canada
| | - Jonathan H Teichroeb
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada
| | | | - Dean H Betts
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada.
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35
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Khan T, Weber H, DiMuzio J, Matter A, Dogdas B, Shah T, Thankappan A, Disa J, Jadhav V, Lubbers L, Sepp-Lorenzino L, Strapps WR, Tadin-Strapps M. Silencing Myostatin Using Cholesterol-conjugated siRNAs Induces Muscle Growth. MOLECULAR THERAPY-NUCLEIC ACIDS 2016; 5:e342. [PMID: 27483025 PMCID: PMC5023400 DOI: 10.1038/mtna.2016.55] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 06/13/2016] [Indexed: 01/13/2023]
Abstract
Short interfering RNAs (siRNAs) are a valuable tool for gene silencing with applications in both target validation and therapeutics. Many advances have recently been made to improve potency and specificity, and reduce toxicity and immunostimulation. However, siRNA delivery to a variety of tissues remains an obstacle for this technology. To date, siRNA delivery to muscle has only been achieved by local administration or by methods with limited potential use in the clinic. We report systemic delivery of a highly chemically modified cholesterol-conjugated siRNA targeting muscle-specific gene myostatin (Mstn) to a full range of muscles in mice. Following a single intravenous injection, we observe 85–95% knockdown of Mstn mRNA in skeletal muscle and >65% reduction in circulating Mstn protein sustained for >21 days. This level of Mstn knockdown is also accompanied by a functional effect on skeletal muscle, with animals showing an increase in muscle mass, size, and strength. The cholesterol-conjugated siRNA platform described here could have major implications for treatment of a variety of muscle disorders, including muscular atrophic diseases, muscular dystrophy, and type II diabetes.
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Affiliation(s)
- Tayeba Khan
- Department of RNA Therapeutics Discovery Biology, Merck and Co., Inc, West Point, Pennsylvania, USA
| | - Hans Weber
- Department of In Vivo Pharmacology, Merck and Co., Inc, West Point, Pennsylvania, USA
| | - Jillian DiMuzio
- Department of RNA Therapeutics Discovery Biology, Merck and Co., Inc, West Point, Pennsylvania, USA
| | - Andrea Matter
- Department of RNA Therapeutics Discovery Biology, Merck and Co., Inc, West Point, Pennsylvania, USA
| | - Belma Dogdas
- Department of Applied Mathematics and Modeling- Scientific Informatics, Merck and Co., Inc, Rahway, New Jersey, USA
| | - Tosha Shah
- Department of Applied Mathematics and Modeling- Scientific Informatics, Merck and Co., Inc, Rahway, New Jersey, USA
| | - Anil Thankappan
- Department of RNA Therapeutics Discovery Biology, Merck and Co., Inc, West Point, Pennsylvania, USA
| | - Jyoti Disa
- Department of Genetics and Pharmacogenomics, Merck and Co., Inc, Boston, Massachusetts, USA
| | - Vasant Jadhav
- Department of RNA Therapeutics Discovery Biology, Merck and Co., Inc, West Point, Pennsylvania, USA
| | - Laura Lubbers
- Department of In Vivo Pharmacology, Merck and Co., Inc, West Point, Pennsylvania, USA
| | - Laura Sepp-Lorenzino
- Department of RNA Therapeutics Discovery Biology, Merck and Co., Inc, West Point, Pennsylvania, USA
| | - Walter R Strapps
- Department of RNA Therapeutics Discovery Biology, Merck and Co., Inc, West Point, Pennsylvania, USA
| | - Marija Tadin-Strapps
- Department of Genetics and Pharmacogenomics, Merck and Co., Inc, Boston, Massachusetts, USA
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Hexose enhances oligonucleotide delivery and exon skipping in dystrophin-deficient mdx mice. Nat Commun 2016; 7:10981. [PMID: 26964641 PMCID: PMC4793046 DOI: 10.1038/ncomms10981] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 02/08/2016] [Indexed: 12/21/2022] Open
Abstract
Carbohydrate-based infusion solutions are widely used in the clinic. Here we show that co-administration of phosphorodiamidate morpholino oligomers (PMOs) with glucose enhances exon-skipping activity in Duchenne muscular dystrophy (DMD) mdx mice. We identify a glucose-fructose (GF) formulation that potentiates PMO activity, completely corrects aberrant Dmd transcripts, restores dystrophin levels in skeletal muscles and achieves functional rescue without detectable toxicity. This activity is attributed to enhancement of GF-mediated PMO uptake in the muscle. We demonstrate that PMO cellular uptake is energy dependent, and that ATP from GF metabolism contributes to enhanced cellular uptake of PMO in the muscle. Collectively, we show that GF potentiates PMO activity by replenishing cellular energy stores under energy-deficient conditions in mdx mice. Our findings provide mechanistic insight into hexose-mediated oligonucleotide delivery and have important implications for the development of DMD exon-skipping therapy.
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Bao TL, Veedu RN, Fletcher S, Wilton SD. Antisense oligonucleotide development for the treatment of muscular dystrophies. Expert Opin Orphan Drugs 2015. [DOI: 10.1517/21678707.2016.1122517] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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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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Wilton SD, Veedu RN, Fletcher S. The emperor's new dystrophin: finding sense in the noise. Trends Mol Med 2015; 21:417-26. [PMID: 26051381 DOI: 10.1016/j.molmed.2015.04.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 04/29/2015] [Accepted: 04/30/2015] [Indexed: 01/16/2023]
Abstract
Targeted dystrophin exon removal is a promising therapy for Duchenne muscular dystrophy (DMD); however, dystrophin expression in some reports is not supported by the associated data. As in the account of 'The Emperor's New Clothes', the validity of such claims must be questioned, with critical re-evaluation of available data. Is it appropriate to report clinical benefit and induction of dystrophin as dose dependent when the baseline is unclear? The inability to induce meaningful levels of dystrophin does not mean that dystrophin expression as an end point is irrelevant, nor that induced exon skipping as a strategy is flawed, but demands that drug safety and efficacy, and study parameters be addressed, rather than questioning the strategy or the validity of dystrophin as a biomarker.
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Affiliation(s)
- S D Wilton
- Centre for Comparative Genomics, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia; West Australian Neuroscience Research Institute, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia.
| | - R N Veedu
- Centre for Comparative Genomics, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia; West Australian Neuroscience Research Institute, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia
| | - S Fletcher
- Centre for Comparative Genomics, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia; West Australian Neuroscience Research Institute, Murdoch University, 90 South Street, Murdoch, WA 6009, Australia
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40
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Järver P, Zaghloul EM, Arzumanov AA, Saleh AF, McClorey G, Hammond SM, Hällbrink M, Langel Ü, Smith CIE, Wood MJA, Gait MJ, El Andaloussi S. Peptide nanoparticle delivery of charge-neutral splice-switching morpholino oligonucleotides. Nucleic Acid Ther 2015; 25:65-77. [PMID: 25594433 PMCID: PMC4376484 DOI: 10.1089/nat.2014.0511] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Oligonucleotide analogs have provided novel therapeutics targeting various disorders. However, their poor cellular uptake remains a major obstacle for their clinical development. Negatively charged oligonucleotides, such as 2′-O-Methyl RNA and locked nucleic acids have in recent years been delivered successfully into cells through complex formation with cationic polymers, peptides, liposomes, or similar nanoparticle delivery systems. However, due to the lack of electrostatic interactions, this promising delivery method has been unsuccessful to date using charge-neutral oligonucleotide analogs. We show here that lipid-functionalized cell-penetrating peptides can be efficiently exploited for cellular transfection of the charge-neutral oligonucleotide analog phosphorodiamidate morpholino. The lipopeptides form complexes with splice-switching phosphorodiamidate morpholino oligonucleotide and can be delivered into clinically relevant cell lines that are otherwise difficult to transfect while retaining biological activity. To our knowledge, this is the first study to show delivery through complex formation of biologically active charge-neutral oligonucleotides by cationic peptides.
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Affiliation(s)
- Peter Järver
- 1 Medical Research Council , Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, United Kingdom
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41
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Brolin C, Shiraishi T. Antisense mediated exon skipping therapy for duchenne muscular dystrophy (DMD). ARTIFICIAL DNA, PNA & XNA 2014; 2:6-15. [PMID: 21686247 DOI: 10.4161/adna.2.1.15425] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 03/07/2011] [Accepted: 03/10/2011] [Indexed: 11/19/2022]
Abstract
Duchenne Muscular Dystrophy (DMD) is a lethal disease caused by mutations in the dystrophin gene (DMD) that result in the absence of essential muscle protein dystrophin. Among many different approaches for DMD treatment, exon skipping, mediated by antisense oligonucleotides, is one of the most promising methods for restoration of dystrophin expression. This approach has been tested extensively targeting different exons in numerous models both in vitro and in vivo. During the past 10 years, there has been a considerable progress by using DMD animal models involving three types of antisense oligonucleotides (2'-O-methyl phosphorothioate (2OME-PS), phosphorodiamidate morpholino oligomer (PMO)) and peptide nucleic acid (PNA).
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Affiliation(s)
- Camilla Brolin
- Center for Experimental Drug and Gene Electrotransfer (CEDGE); Department of Oncology 54B1; Copenhagen University Hospital Herlev, Copenhagen, Denmark
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42
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Siva K, Covello G, Denti MA. Exon-skipping antisense oligonucleotides to correct missplicing in neurogenetic diseases. Nucleic Acid Ther 2014; 24:69-86. [PMID: 24506781 DOI: 10.1089/nat.2013.0461] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Alternative splicing is an important regulator of the transcriptome. However, mutations may cause alteration of splicing patterns, which in turn leads to disease. During the past 10 years, exon skipping has been looked upon as a powerful tool for correction of missplicing in disease and progress has been made towards clinical trials. In this review, we discuss the use of antisense oligonucleotides to correct splicing defects through exon skipping, with a special focus on diseases affecting the nervous system, and the latest stage achieved in its progress.
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Affiliation(s)
- Kavitha Siva
- 1 Center for Integrative Biology (CIBIO), University of Trento , Trento, Italy
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43
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Falzarano MS, Passarelli C, Ferlini A. Nanoparticle delivery of antisense oligonucleotides and their application in the exon skipping strategy for Duchenne muscular dystrophy. Nucleic Acid Ther 2014; 24:87-100. [PMID: 24506782 DOI: 10.1089/nat.2013.0450] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Antisense therapy is a powerful tool for inducing post-transcriptional modifications and thereby regulating target genes associated with disease. There are several classes of antisense oligonucleotides (AONs) with therapeutic use, such as double-stranded RNAs (interfering RNAs, utilized for gene silencing, and single-stranded AONs with various chemistries, which are useful for antisense targeting of micro-RNAs and mRNAs. In particular, the use of AONs for exon skipping, by targeting pre-mRNA, is proving to be a highly promising therapy for some genetic disorders like Duchenne muscular dystrophy and spinal muscular atrophy. However, AONs are unable to cross the plasma membrane unaided, and several other obstacles still remain to be overcome, in particular their instability due to their nuclease sensitivity and their lack of tissue specificity. Various drug delivery systems have been explored to improve the bioavailability of nucleic acids, and nanoparticles (NPs) have been suggested as potential vectors for DNA/RNA. This review describes the recent progress in AON conjugation with natural and synthetic delivery systems, and provides an overview of the efficacy of NP-AON complexes as an exon-skipping treatment for Duchenne muscular dystrophy.
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Affiliation(s)
- Maria Sofia Falzarano
- 1 Section of Microbiology and Medical Genetics, Department of Medical Sciences, University of Ferrara , Ferrara, Italy
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44
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Impaired functional communication between the L-type calcium channel and mitochondria contributes to metabolic inhibition in the mdx heart. Proc Natl Acad Sci U S A 2014; 111:E2905-14. [PMID: 24969422 DOI: 10.1073/pnas.1402544111] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Duchenne muscular dystrophy is a fatal X-linked disease characterized by the absence of dystrophin. Approximately 20% of boys will die of dilated cardiomyopathy that is associated with cytoskeletal protein disarray, contractile dysfunction, and reduced energy production. However, the mechanisms for altered energy metabolism are not yet fully clarified. Calcium influx through the L-type Ca(2+) channel is critical for maintaining cardiac excitation and contraction. The L-type Ca(2+) channel also regulates mitochondrial function and metabolic activity via transmission of movement of the auxiliary beta subunit through intermediate filament proteins. Here, we find that activation of the L-type Ca(2+) channel is unable to induce increases in mitochondrial membrane potential and metabolic activity in intact cardiac myocytes from the murine model of Duchenne muscular dystrophy (mdx) despite robust increases recorded in wt myocytes. Treatment of mdx mice with morpholino oligomers to induce exon skipping of dystrophin exon 23 (that results in functional dystrophin accumulation) or application of a peptide that resulted in block of voltage-dependent anion channel (VDAC) "rescued" mitochondrial membrane potential and metabolic activity in mdx myocytes. The mitochondrial VDAC coimmunoprecipitated with the L-type Ca(2+) channel. We conclude that the absence of dystrophin in the mdx ventricular myocyte leads to impaired functional communication between the L-type Ca(2+) channel and mitochondrial VDAC. This appears to contribute to metabolic inhibition. These findings provide new mechanistic and functional insight into cardiomyopathy associated with Duchenne muscular dystrophy.
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45
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Radan L, Hughes CS, Teichroeb JH, Vieira Zamora FM, Jewer M, Postovit LM, Betts DH. Microenvironmental regulation of telomerase isoforms in human embryonic stem cells. Stem Cells Dev 2014; 23:2046-66. [PMID: 24749509 DOI: 10.1089/scd.2013.0373] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Recent evidence points to extra-telomeric, noncanonical roles for telomerase in regulating stem cell function. In this study, human embryonic stem cells (hESCs) were cultured in 20% or 2% O2 microenvironments for up to 5 days and evaluated for telomerase reverse transcriptase (TERT) expression and telomerase activity. Results showed increased cell survival and maintenance of the undifferentiated state with elevated levels of nuclear TERT in 2% O2-cultured hESCs despite no significant difference in telomerase activity compared with their high-O2-cultured counterparts. Pharmacological inhibition of telomerase activity using a synthetic tea catechin resulted in spontaneous hESC differentiation, while telomerase inhibition with a phosphorothioate oligonucleotide telomere mimic did not. Reverse transcription polymerase chain reaction (RT-PCR) analysis revealed variations in transcript levels of full-length and alternate splice variants of TERT in hESCs cultured under varying O2 atmospheres. Steric-blocking of Δα and Δβ hTERT splicing using morpholino oligonucleotides altered the hTERT splicing pattern and rapidly induced spontaneous hESC differentiation that appeared biased toward endomesodermal and neuroectodermal cell fates, respectively. Together, these results suggest that post-transcriptional regulation of TERT under varying O2 microenvironments may help regulate hESC survival, self-renewal, and differentiation capabilities through expression of extra-telomeric telomerase isoforms.
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Affiliation(s)
- Lida Radan
- 1 Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, University of Western Ontario , London, Ontario, Canada
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46
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Shabanpoor F, Gait MJ. Development of a general methodology for labelling peptide-morpholino oligonucleotide conjugates using alkyne-azide click chemistry. Chem Commun (Camb) 2014; 49:10260-2. [PMID: 24064913 PMCID: PMC3816334 DOI: 10.1039/c3cc46067c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A general and convenient solid-phase synthesis method using Cu(i)-mediated alkyne–azide click chemistry for attachment of an azide derivative of a fluorescent label to an alkyne derivative of a peptide conjugated to a morpholino oligonucleotide (PMO).
We describe a general methodology for fluorescent labelling of peptide conjugates of phosphorodiamidate morpholino oligonucleotides (PMOs) by alkyne functionalization of peptides, subsequent conjugation to PMOs and labelling with a fluorescent compound (Cy5-azide). Two peptide–PMO (PPMO) examples are shown. No detrimental effect of such labelled PMOs was seen in a biological assay.
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47
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Wang M, Wu B, Tucker JD, Lu P, Cloer C, Lu QL. Evaluation of Tris[2-(acryloyloxy)ethyl]isocyanurate cross-linked polyethylenimine as antisense morpholino oligomer delivery vehicle in cell culture and dystrophic mdx mice. Hum Gene Ther 2014; 25:419-27. [PMID: 24405395 DOI: 10.1089/hum.2013.156] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Hyperbranched poly(ester amine)s (PEAs) based on tris[2-(acryloyloxy)ethyl]isocyanurate (TAEI) cross-linked low-molecular-weight polyethylenimine (Mw: 0.8k/1.2k/2.0k) have been evaluated for delivering antisense phosphorodiamidate morpholino oligomer (PMO) in vitro and in vivo in the dystrophic mdx mouse. The results show that the PEAs constructed with polyethylenimine (PEI) 2.0k (C series) improved PMO delivery more efficiently than those constructed with PEI 0.8k (A series) or 1.2k (B series) in a GFP reporter-based C2C12 mouse myoblast culture system. The highest efficiency of exon-skipping in vitro with the PMO oligonucleotide targeting human dystrophin exon 50 was obtained when the PEA C12 [TAEI-PEI 2.0k (1:2)] was used. Nearly all of the PEAs improved dystrophin expression in mdx mice by local injection with a 2-4-fold increase when compared with PMO alone. Improved transfection efficiency and lower toxicity indicate the potential of the biodegradable PEA polymers as safe and efficient PMO delivery vectors for in vivo applications.
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Affiliation(s)
- Mingxing Wang
- 1 Department of Neurology, McColl-Lockwood Laboratory for Muscular Dystrophy Research, Cannon Research Center , Carolinas Medical Center, Charlotte, NC 28231
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48
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Negishi Y, Ishii Y, Shiono H, Akiyama S, Sekine S, Kojima T, Mayama S, Kikuchi T, Hamano N, Endo-Takahashi Y, Suzuki R, Maruyama K, Aramaki Y. Bubble liposomes and ultrasound exposure improve localized morpholino oligomer delivery into the skeletal muscles of dystrophic mdx mice. Mol Pharm 2014; 11:1053-61. [PMID: 24433046 DOI: 10.1021/mp4004755] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Duchenne muscular dystrophy (DMD) is a genetic disorder that is caused by mutations in the DMD gene that lead to an absence of functional protein. The mdx dystrophic mouse contains a nonsense mutation in exon 23 of the dystrophin gene; a phosphorodiamidate morpholino oligomer (PMO) designed to skip this mutated exon in the mRNA induces dystrophin expression. However, an efficient PMO delivery method is needed to improve treatment strategies for DMD. We previously developed polyethylene glycol (PEG)-modified liposomes (Bubble liposomes) that entrap ultrasound contrast gas and demonstrated that the combination of Bubble liposomes with ultrasound exposure is an effective gene delivery tool in vitro and in vivo. In this study, to evaluate the ability of Bubble liposomes as a PMO delivery tool, we tested the potency of the Bubble liposomes combined with ultrasound exposure to boost the delivery of PMO and increase the skipping of the mutated exon in the mdx mouse. The results indicated that the combination of Bubble liposomes and ultrasound exposure increased the uptake of the PMO targeting a nonsense mutation in exon 23 of the dystrophin gene and consequently increased the PMO-mediated exon-skipping efficiency compared with PMO injection alone, leading to significantly enhanced dystrophin expression. This increased efficiency indicated the potential of the combination of Bubble liposomes with ultrasound exposure to enhance PMO delivery for treating DMD. Thus, this ultrasound-mediated Bubble liposome technique may provide an effective, noninvasive, nonviral method for PMO therapy for DMD muscle as well as for other muscular dystrophies.
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Affiliation(s)
- Yoichi Negishi
- Department of Drug Delivery and Molecular Biopharmaceutics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
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49
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Echigoya Y, Yokota T. Skipping multiple exons of dystrophin transcripts using cocktail antisense oligonucleotides. Nucleic Acid Ther 2013; 24:57-68. [PMID: 24380394 DOI: 10.1089/nat.2013.0451] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is one of the most common and lethal genetic disorders, with 20,000 children per year born with DMD globally. DMD is caused by mutations in the dystrophin (DMD) gene. Antisense-mediated exon skipping therapy is a promising therapeutic approach that uses short DNA-like molecules called antisense oligonucleotides (AOs) to skip over/splice out the mutated part of the gene to produce a shortened but functional dystrophin protein. One major challenge has been its limited applicability. Multiple exon skipping has recently emerged as a potential solution. Indeed, many DMD patients need exon skipping of multiple exons in order to restore the reading frame, depending on how many base pairs the mutated exon(s) and adjacent exons have. Theoretically, multiple exon skipping could be used to treat approximately 90%, 80%, and 98% of DMD patients with deletion, duplication, and nonsense mutations, respectively. In addition, multiple exon skipping could be used to select deletions that optimize the functionality of the truncated dystrophin protein. The proof of concept of systemic multiple exon skipping using a cocktail of AOs has been demonstrated in dystrophic dog and mouse models. Remaining challenges include the insufficient efficacy of systemic treatment, especially for therapies that target the heart, and limited long-term safety data. Here we review recent preclinical developments in AO-mediated multiple exon skipping and discuss the remaining challenges.
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Affiliation(s)
- Yusuke Echigoya
- 1 Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta , Edmonton, Alberta, Canada
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50
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Davila D, Thibault K, Fiacco TA, Agulhon C. Recent molecular approaches to understanding astrocyte function in vivo. Front Cell Neurosci 2013; 7:272. [PMID: 24399932 PMCID: PMC3871966 DOI: 10.3389/fncel.2013.00272] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 12/06/2013] [Indexed: 12/11/2022] Open
Abstract
Astrocytes are a predominant glial cell type in the nervous systems, and are becoming recognized as important mediators of normal brain function as well as neurodevelopmental, neurological, and neurodegenerative brain diseases. Although numerous potential mechanisms have been proposed to explain the role of astrocytes in the normal and diseased brain, research into the physiological relevance of these mechanisms in vivo is just beginning. In this review, we will summarize recent developments in innovative and powerful molecular approaches, including knockout mouse models, transgenic mouse models, and astrocyte-targeted gene transfer/expression, which have led to advances in understanding astrocyte biology in vivo that were heretofore inaccessible to experimentation. We will examine the recently improved understanding of the roles of astrocytes – with an emphasis on astrocyte signaling – in the context of both the healthy and diseased brain, discuss areas where the role of astrocytes remains debated, and suggest new research directions.
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Affiliation(s)
- David Davila
- Glia-Glia and Glia-Neuron Interactions Group, National Center for Scientific Research, UFR Biomedicale, Paris Descartes University Paris, France
| | - Karine Thibault
- Glia-Glia and Glia-Neuron Interactions Group, National Center for Scientific Research, UFR Biomedicale, Paris Descartes University Paris, France
| | - Todd A Fiacco
- Department of Cell Biology and Neuroscience, and Center for Glial-Neuronal Interactions and Program in Cellular, Molecular and Developmental Biology, University of California at Riverside Riverside, CA, USA
| | - Cendra Agulhon
- Glia-Glia and Glia-Neuron Interactions Group, National Center for Scientific Research, UFR Biomedicale, Paris Descartes University Paris, France
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