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Kundu J, Ghosh U, Ghosh A, Pattanayak S, Das A, Sinha S. Synthesis of Chlorophosphoramidate Monomer Morpholinos and PMOs. Curr Protoc 2023; 3:e686. [PMID: 36802170 DOI: 10.1002/cpz1.686] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Phosphorodiamidate morpholino oligonucleotides (PMOs) are a successful class of antisense reagents that efficiently modulate gene expression. Because PMOs do not follow standard phosphoramidite chemistry, optimized synthetic protocols for these compounds are relatively scarce in the literature. This paper presents detailed protocols for synthesizing full-length PMOs using chlorophosphoramidate chemistry by manual solid-phase synthesis. We first describe the synthesis of Fmoc-protected morpholino hydroxyl monomers, and the corresponding chlorophosphoramidate monomers, from commercially available protected ribonucleosides. The new Fmoc chemistry necessitates the use of a milder base, such as N-ethylmorpholine (NEM), and coupling reagent, such as 5-(ethylthio)-1H-tetrazole (ETT), which are also tolerated for acid-sensitive trityl chemistry. These chlorophosphoramidate monomers are then employed for PMO synthesis in a manual solid-phase procedure using four sequential steps. The synthetic cycle for each nucleotide incorporation consists of (a) deblocking of the 3'-N protecting group using an acidic deblocking cocktail for trityl and base deblocking for Fmoc, (b) neutralization, (c) coupling in the presence of ETT and NEM, and (d) capping of the unreacted morpholine ring-amine. The method uses safe, stable, and inexpensive reagents, and the process is expected to be scalable. After full-length PMO synthesis and ammonia-mediated cleavage from the solid support and deprotection, a range of PMOs with different lengths can be obtained conveniently and efficiently with reproducible good yields. © 2023 Wiley Periodicals LLC. Basic Protocol 1: Synthesis of the novel Fmoc-protected morpholino monomers Basic Protocol 2: Synthesis of the phosphorylating reagent (N,N-dimethylphosphoramic dichloride) required for chlorophosphoramidate monomer synthesis Basic Protocol 3: Synthesis of chlorophosphoramidate monomers of Fmoc-protected morpholino monomers Basic Protocol 4: Solution-phase standardization of dimer and trimer PMO synthesis using Fmoc chemistry Basic Protocol 5: Solid-phase synthesis, purification, and characterization of full-length (25-mer) no-tail PMO using both trityl and Fmoc chemistry.
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Affiliation(s)
- Jayanta Kundu
- School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation of Science, Kolkata, India
| | - Ujjwal Ghosh
- School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation of Science, Kolkata, India
| | - Atanu Ghosh
- School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation of Science, Kolkata, India
| | - Sankha Pattanayak
- School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation of Science, Kolkata, India
| | - Arnab Das
- School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation of Science, Kolkata, India
| | - Surajit Sinha
- School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation of Science, Kolkata, India
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Li PP, Moulick R, Feng H, Sun X, Arbez N, Jin J, Marque LO, Hedglen E, Chan HE, Ross CA, Pulst SM, Margolis RL, Woodson S, Rudnicki DD. RNA Toxicity and Perturbation of rRNA Processing in Spinocerebellar Ataxia Type 2. Mov Disord 2021; 36:2519-2529. [PMID: 34390268 PMCID: PMC8884117 DOI: 10.1002/mds.28729] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 06/03/2021] [Accepted: 07/12/2021] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Spinocerebellar ataxia type 2 (SCA2) is a neurodegenerative disease caused by expansion of a CAG repeat in Ataxin-2 (ATXN2) gene. The mutant ATXN2 protein with a polyglutamine tract is known to be toxic and contributes to the SCA2 pathogenesis. OBJECTIVE Here, we tested the hypothesis that the mutant ATXN2 transcript with an expanded CAG repeat (expATXN2) is also toxic and contributes to SCA2 pathogenesis. METHODS The toxic effect of expATXN2 transcripts on SK-N-MC neuroblastoma cells and primary mouse cortical neurons was evaluated by caspase 3/7 activity and nuclear condensation assay, respectively. RNA immunoprecipitation assay was performed to identify RNA binding proteins (RBPs) that bind to expATXN2 RNA. Quantitative PCR was used to examine if ribosomal RNA (rRNA) processing is disrupted in SCA2 and Huntington's disease (HD) human brain tissue. RESULTS expATXN2 RNA induces neuronal cell death, and aberrantly interacts with RBPs involved in RNA metabolism. One of the RBPs, transducin β-like protein 3 (TBL3), involved in rRNA processing, binds to both expATXN2 and expanded huntingtin (expHTT) RNA in vitro. rRNA processing is disrupted in both SCA2 and HD human brain tissue. CONCLUSION These findings provide the first evidence of a contributory role of expATXN2 transcripts in SCA2 pathogenesis, and further support the role of expHTT transcripts in HD pathogenesis. The disruption of rRNA processing, mediated by aberrant interaction of RBPs with expATXN2 and expHTT transcripts, suggest a point of convergence in the pathogeneses of repeat expansion diseases with potential therapeutic implications. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Pan P. Li
- Department of Psychiatry and Behavioral Sciences, Division of NeurobiologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Roumita Moulick
- T.C. Jenkins Department of BiophysicsJohns Hopkins UniversityBaltimoreMarylandUSA
| | - Hongxuan Feng
- Department of Psychiatry and Behavioral Sciences, Division of NeurobiologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Xin Sun
- Department of Psychiatry and Behavioral Sciences, Division of NeurobiologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Nicolas Arbez
- Department of Psychiatry and Behavioral Sciences, Division of NeurobiologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Jing Jin
- Department of Psychiatry and Behavioral Sciences, Division of NeurobiologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Leonard O. Marque
- Department of Psychiatry and Behavioral Sciences, Division of NeurobiologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Erin Hedglen
- Department of Psychiatry and Behavioral Sciences, Division of NeurobiologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - H.Y. Edwin Chan
- Biochemistry Program, School of Life SciencesThe Chinese University of Hong KongHong KongChina
| | - Christopher A. Ross
- Department of Psychiatry and Behavioral Sciences, Division of NeurobiologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
- Department of NeurologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
- Department of NeuroscienceJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Stefan M. Pulst
- Department of NeurologyUniversity of UtahSalt Lake CityUtahUSA
| | - Russell L. Margolis
- Department of Psychiatry and Behavioral Sciences, Division of NeurobiologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
- Department of NeurologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Sarah Woodson
- T.C. Jenkins Department of BiophysicsJohns Hopkins UniversityBaltimoreMarylandUSA
| | - Dobrila D. Rudnicki
- Department of Psychiatry and Behavioral Sciences, Division of NeurobiologyJohns Hopkins University School of MedicineBaltimoreMarylandUSA
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Borbolla-Jiménez FV, Del Prado-Audelo ML, Cisneros B, Caballero-Florán IH, Leyva-Gómez G, Magaña JJ. New Perspectives of Gene Therapy on Polyglutamine Spinocerebellar Ataxias: From Molecular Targets to Novel Nanovectors. Pharmaceutics 2021; 13:1018. [PMID: 34371710 PMCID: PMC8309146 DOI: 10.3390/pharmaceutics13071018] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/25/2021] [Accepted: 06/29/2021] [Indexed: 01/03/2023] Open
Abstract
Seven of the most frequent spinocerebellar ataxias (SCAs) are caused by a pathological expansion of a cytosine, adenine and guanine (CAG) trinucleotide repeat located in exonic regions of unrelated genes, which in turn leads to the synthesis of polyglutamine (polyQ) proteins. PolyQ proteins are prone to aggregate and form intracellular inclusions, which alter diverse cellular pathways, including transcriptional regulation, protein clearance, calcium homeostasis and apoptosis, ultimately leading to neurodegeneration. At present, treatment for SCAs is limited to symptomatic intervention, and there is no therapeutic approach to prevent or reverse disease progression. This review provides a compilation of the experimental advances obtained in cell-based and animal models toward the development of gene therapy strategies against polyQ SCAs, providing a discussion of their potential application in clinical trials. In the second part, we describe the promising potential of nanotechnology developments to treat polyQ SCA diseases. We describe, in detail, how the design of nanoparticle (NP) systems with different physicochemical and functionalization characteristics has been approached, in order to determine their ability to evade the immune system response and to enhance brain delivery of molecular tools. In the final part of this review, the imminent application of NP-based strategies in clinical trials for the treatment of polyQ SCA diseases is discussed.
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Affiliation(s)
- Fabiola V. Borbolla-Jiménez
- Laboratorio de Medicina Genómica, Departamento de Genética, Instituto Nacional de Rehabilitación-Luis Guillermo Ibarra Ibarra, Ciudad de México 14389, Mexico;
- Programa de Ciencias Biomédicas, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico
| | - María Luisa Del Prado-Audelo
- Departamento de Bioingeniería, Escuela de Ingeniería y Ciencias, Tecnológico de Monterrey Campus Ciudad de México, Ciudad de México 14380, Mexico;
| | - Bulmaro Cisneros
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Ciudad de México 07360, Mexico;
| | - Isaac H. Caballero-Florán
- Departamento de Farmacia, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico;
- Departamento de Farmacia, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Ciudad de México 07360, Mexico
| | - Gerardo Leyva-Gómez
- Departamento de Farmacia, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México 04510, Mexico;
| | - Jonathan J. Magaña
- Laboratorio de Medicina Genómica, Departamento de Genética, Instituto Nacional de Rehabilitación-Luis Guillermo Ibarra Ibarra, Ciudad de México 14389, Mexico;
- Departamento de Bioingeniería, Escuela de Ingeniería y Ciencias, Tecnológico de Monterrey Campus Ciudad de México, Ciudad de México 14380, Mexico;
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Selective suppression of polyglutamine-expanded protein by lipid nanoparticle-delivered siRNA targeting CAG expansions in the mouse CNS. MOLECULAR THERAPY. NUCLEIC ACIDS 2021; 24:1-10. [PMID: 33738134 PMCID: PMC7937577 DOI: 10.1016/j.omtn.2021.02.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 02/09/2021] [Indexed: 12/11/2022]
Abstract
Polyglutamine (polyQ) diseases are inherited neurodegenerative disorders caused by expansion of cytosine-adenine-guanine (CAG)-trinucleotide repeats in causative genes. These diseases include spinal and bulbar muscular atrophy (SBMA), Huntington’s disease, dentatorubral-pallidoluysian atrophy, and spinocerebellar ataxias. Targeting expanded CAG repeats is a common therapeutic approach to polyQ diseases, but concomitant silencing of genes with normal CAG repeats may lead to toxicity. Previous studies have shown that CAG repeat-targeting small interfering RNA duplexes (CAG-siRNAs) have the potential to selectively suppress mutant proteins in in vitro cell models of polyQ diseases. However, in vivo application of these siRNAs has not yet been investigated. In this study, we demonstrate that an unlocked nucleic acid (UNA)-modified CAG-siRNA shows high selectivity for polyQ-expanded androgen receptor (AR) inhibition in in vitro cell models and that lipid nanoparticle (LNP)-mediated delivery of the CAG-siRNA selectively suppresses mutant AR in the central nervous system of an SBMA mouse model. In addition, a subcutaneous injection of the LNP-delivered CAG-siRNA efficiently suppresses mutant AR in the skeletal muscle of the SBMA mouse model. These results support the therapeutic potential of LNP-delivered UNA-modified CAG-siRNAs for selective suppression of mutant proteins in SBMA and other polyQ diseases.
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5
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Minakawa EN, Nagai Y. Protein Aggregation Inhibitors as Disease-Modifying Therapies for Polyglutamine Diseases. Front Neurosci 2021; 15:621996. [PMID: 33642983 PMCID: PMC7907447 DOI: 10.3389/fnins.2021.621996] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 01/18/2021] [Indexed: 12/11/2022] Open
Abstract
The polyglutamine (polyQ) diseases are a group of inherited neurodegenerative diseases caused by the abnormal expansion of a CAG trinucleotide repeat that are translated into an expanded polyQ stretch in the disease-causative proteins. The expanded polyQ stretch itself plays a critical disease-causative role in the pathomechanisms underlying polyQ diseases. Notably, the expanded polyQ stretch undergoes a conformational transition from the native monomer into the β-sheet-rich monomer, followed by the formation of soluble oligomers and then insoluble aggregates with amyloid fibrillar structures. The intermediate soluble species including the β-sheet-rich monomer and oligomers exhibit substantial neurotoxicity. Therefore, protein conformation stabilization and aggregation inhibition that target the upstream of the insoluble aggregate formation would be a promising approach toward the development of disease-modifying therapies for polyQ diseases. PolyQ aggregation inhibitors of different chemical categories, such as intrabodies, peptides, and small chemical compounds, have been identified through intensive screening methods. Among them, recent advances in the brain delivery methods of several peptides and the screening of small chemical compounds have brought them closer to clinical utility. Notably, the recent discovery of arginine as a potent conformation stabilizer and aggregation inhibitor of polyQ proteins both in vitro and in vivo have paved way to the clinical trial for the patients with polyQ diseases. Meanwhile, expression reduction of expanded polyQ proteins per se would be another promising approach toward disease modification of polyQ diseases. Gene silencing, especially by antisense oligonucleotides (ASOs), have succeeded in reducing the expression of polyQ proteins in the animal models of various polyQ diseases by targeting the aberrant mRNA with expanded CAG repeats. Of note, some of these ASOs have recently been translated into clinical trials. Here we overview and discuss these recent advances toward the development of disease modifying therapies for polyQ diseases. We envision that combination therapies using aggregation inhibitors and gene silencing would meet the needs of the patients with polyQ diseases and their caregivers in the near future to delay or prevent the onset and progression of these currently intractable diseases.
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Affiliation(s)
- Eiko N Minakawa
- Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Japan
| | - Yoshitaka Nagai
- Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Japan.,Department of Neurotherapeutics, Osaka University Graduate School of Medicine, Suita, Japan
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6
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Doxakis E. Therapeutic antisense oligonucleotides for movement disorders. Med Res Rev 2020; 41:2656-2688. [PMID: 32656818 DOI: 10.1002/med.21706] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 06/11/2020] [Accepted: 06/26/2020] [Indexed: 12/11/2022]
Abstract
Movement disorders are a group of neurological conditions characterized by abnormalities of movement and posture. They are broadly divided into akinetic and hyperkinetic syndromes. Until now, no effective symptomatic or disease-modifying therapies have been available. However, since many of these disorders are monogenic or have some well-defined genetic component, they represent strong candidates for antisense oligonucleotide (ASO) therapies. ASO therapies are based on the use of short synthetic single-stranded ASOs that bind to disease-related target RNAs via Watson-Crick base-pairing and pleiotropically modulate their function. With information arising from the RNA sequence alone, it is possible to design ASOs that not only alter the expression levels but also the splicing defects of any protein, far exceeding the intervention repertoire of traditional small molecule approaches. Following the regulatory approval of ASO therapies for spinal muscular atrophy and Duchenne muscular dystrophy in 2016, there has been tremendous momentum in testing such therapies for other neurological disorders. This review article initially focuses on the chemical modifications aimed at improving ASO effectiveness, the mechanisms by which ASOs can interfere with RNA function, delivery systems and pharmacokinetics, and the common set of toxicities associated with their application. It, then, describes the pathophysiology and the latest information on preclinical and clinical trials utilizing ASOs for the treatment of Parkinson's disease, Huntington's disease, and ataxias 1, 2, 3, and 7. It concludes with issues that require special attention to realize the full potential of ASO-based therapies.
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Affiliation(s)
- Epaminondas Doxakis
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Athens, Greece
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7
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Silva AC, Lobo DD, Martins IM, Lopes SM, Henriques C, Duarte SP, Dodart JC, Nobre RJ, Pereira de Almeida L. Antisense oligonucleotide therapeutics in neurodegenerative diseases: the case of polyglutamine disorders. Brain 2020; 143:407-429. [PMID: 31738395 DOI: 10.1093/brain/awz328] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 08/09/2019] [Accepted: 08/22/2019] [Indexed: 12/20/2022] Open
Abstract
Polyglutamine (polyQ) disorders are a group of nine neurodegenerative diseases that share a common genetic cause, which is an expansion of CAG repeats in the coding region of the causative genes that are otherwise unrelated. The trinucleotide expansion encodes for an expanded polyQ tract in the respective proteins, resulting in toxic gain-of-function and eventually in neurodegeneration. Currently, no disease-modifying therapies are available for this group of disorders. Nevertheless, given their monogenic nature, polyQ disorders are ideal candidates for therapies that target specifically the gene transcripts. Antisense oligonucleotides (ASOs) have been under intense investigation over recent years as gene silencing tools. ASOs are small synthetic single-stranded chains of nucleic acids that target specific RNA transcripts through several mechanisms. ASOs can reduce the levels of mutant proteins by breaking down the targeted transcript, inhibit mRNA translation or alter the maturation of the pre-mRNA via splicing correction. Over the years, chemical optimization of ASO molecules has allowed significant improvement of their pharmacological properties, which has in turn made this class of therapeutics a very promising strategy to treat a variety of neurodegenerative diseases. Indeed, preclinical and clinical strategies have been developed in recent years for some polyQ disorders using ASO therapeutics. The success of ASOs in several animal models, as well as encouraging results in the clinic for Huntington's disease, points towards a promising future regarding the application of ASO-based therapies for polyQ disorders in humans, offering new opportunities to address unmet medical needs for this class of disorders. This review aims to present a brief overview of key chemical modifications, mechanisms of action and routes of administration that have been described for ASO-based therapies. Moreover, it presents a review of the most recent and relevant preclinical and clinical trials that have tested ASO therapeutics in polyQ disorders.
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Affiliation(s)
- Ana C Silva
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Diana D Lobo
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Inês M Martins
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Sara M Lopes
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Carina Henriques
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,ViraVector, Viral Vector for Gene Transfer Core Facility, University of Coimbra, Coimbra, Portugal
| | - Sónia P Duarte
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | | | - Rui Jorge Nobre
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal.,ViraVector, Viral Vector for Gene Transfer Core Facility, University of Coimbra, Coimbra, Portugal
| | - Luis Pereira de Almeida
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,ViraVector, Viral Vector for Gene Transfer Core Facility, University of Coimbra, Coimbra, Portugal.,Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
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8
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Wahyuningtyas D, Chen WH, Huang CH, He YJ, Huang JJT. Biocompatible Inhibitor Based on Chitosan and Amphiphilic Peptide against Mutant Huntingtin Toxicity. Chembiochem 2019; 20:2133-2140. [PMID: 31166067 DOI: 10.1002/cbic.201900242] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Indexed: 12/15/2022]
Abstract
Huntington's disease (HD) is classified as a protein-misfolding disease correlated with the mutant Huntingtin (mHtt) protein with abnormally expanded polyglutamine (polyQ) domains. Because no effective drugs have yet been reported, attempts to develop better therapy to delay the age of onset are in urgent demand. In this study, an amphiphilic peptide consisting of negatively charged hexaglutamic acid and a stretch of decaglutamine (E6 Q10 ) was chemically synthesized as an inhibitor against polyQ and mHtt toxicity. It is found that E6 Q10 selfassembles into spherical vesicles, as shown by means of TEM, cryoelectron microscopy, and dynamic light scattering. Assembled E6 Q10 prevented the polyQ-rich peptide (KKWQ20 AKK) from forming amyloid fibrils. To enable the cell-penetration ability of E6 Q10 , the E6 Q10 ⋅chitosan complex was generated. It is demonstrated that the complex penetrates cells, interferes with the mHtt oligomerization and aggregation process, and prevents mHtt cytotoxicity. By combining positively charged chitosan and amphiphilic peptides with a negatively charge moiety, a new strategy is provided to develop biocompatible and biodegradable inhibitors against mHtt toxicity.
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Affiliation(s)
- Devi Wahyuningtyas
- Institute of Chemistry, Academia Sinica, No. 128, Sec. 2, Academia Road, Nankang, Taipei, 115, Taiwan.,Sustainable Chemical Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, No. 128, Sec. 2, Academia Road, Nankang, Taipei, 115, Taiwan.,Department of Applied Chemistry, National Chiao Tung University, Science Building 2, 1001 Ta Hsueh Road, Hsinchu, 300, Taiwan
| | - Wen-Hao Chen
- Institute of Chemistry, Academia Sinica, No. 128, Sec. 2, Academia Road, Nankang, Taipei, 115, Taiwan
| | - Chen-Han Huang
- Department of Biomedical Sciences and Engineering, National Central University, No. 300, Zhongda Road, Zhongli, Taoyuan, 32001, Taiwan
| | - Yu-Jung He
- Institute of Chemistry, Academia Sinica, No. 128, Sec. 2, Academia Road, Nankang, Taipei, 115, Taiwan
| | - Joseph Jen-Tse Huang
- Institute of Chemistry, Academia Sinica, No. 128, Sec. 2, Academia Road, Nankang, Taipei, 115, Taiwan
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9
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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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Imbert M, Blandel F, Leumann C, Garcia L, Goyenvalle A. Lowering Mutant Huntingtin Using Tricyclo-DNA Antisense Oligonucleotides As a Therapeutic Approach for Huntington's Disease. Nucleic Acid Ther 2019; 29:256-265. [PMID: 31184975 DOI: 10.1089/nat.2018.0775] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Huntington's disease is a neurodegenerative disorder caused by a CAG repeat expansion in the first exon of huntingtin gene (HTT) encoding for a toxic polyglutamine protein. This disease is characterized by motor, psychiatric, and cognitive impairments. Currently, there is no disease modifying treatment. However, reducing the expression of the huntingtin protein (HTT) using antisense oligonucleotides (ASOs) has been shown as a promising therapeutic strategy. In this study, we explore the therapeutic potential of ASO made of tricyclo-DNA (tcDNA), a conformationally constrained DNA analog, to silence HTT. We used a gapmer ASO, containing central DNA nucleotides flanked by tcDNA modifications on 5' and 3' ends, allowing the recruitment of RNAse H and subsequent degradation of the messenger RNA. After transfection of tcDNA-ASO in patient-derived fibroblast cell lines, we show a strong decrease of HTT mRNA and protein levels. As a control, 2'O-methyl-RNA targeting the same region of HTT was also tested and did not induce a significant effect. tcDNA-ASO were also evaluated in vivo in the YAC128 mice, containing the full-length human HTT gene with 128 CAG repeat expansion. Single intracerebroventricular (ICV) injections of tcDNA induce a significant decrease of HTT messenger and protein levels in the cortex, hippocampus, striatum, and cerebellum of treated mice. tcDNA-ASO were found well distributed in the central nervous system (CNS) and show long lasting effect with protein levels still low, 12 weeks after a single ICV injection. This proof of concept study suggests the therapeutic potential of gapmer tcDNA ASO to downregulate huntingtin in vitro and in vivo.
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Affiliation(s)
- Marine Imbert
- U1179 INSERM, UFR des Sciences de la Santé-LIA BAHN CSM, Université de Versailles St-Quentin, Montigny le Bretonneux, France
| | - Florence Blandel
- U1179 INSERM, UFR des Sciences de la Santé-LIA BAHN CSM, Université de Versailles St-Quentin, Montigny le Bretonneux, France
| | - Christian Leumann
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Luis Garcia
- U1179 INSERM, UFR des Sciences de la Santé-LIA BAHN CSM, Université de Versailles St-Quentin, Montigny le Bretonneux, France
| | - Aurelie Goyenvalle
- U1179 INSERM, UFR des Sciences de la Santé-LIA BAHN CSM, Université de Versailles St-Quentin, Montigny le Bretonneux, France
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11
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Jensen MP, Barker RA. Disease-Modification in Huntington's Disease: Moving Away from a Single-Target Approach. J Huntingtons Dis 2019; 8:9-22. [PMID: 30636742 DOI: 10.3233/jhd-180320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
To date, no candidate intervention has demonstrated a disease-modifying effect in Huntington's disease, despite promising results in preclinical studies. In this commentary we discuss disease-modifying therapies that have been trialled in Huntington's disease and speculate that these failures may be attributed, in part, to the assumption that a single drug selectively targeting one aspect of disease pathology will be universally effective, regardless of disease stage or "subtype". We therefore propose an alternative approach for effective disease-modification that uses 1) a combination approach rather than monotherapy, and 2) targets the disease process early on - before it is clinically manifest. Finally, we will consider whether this change in approach that we propose will be relevant in the future given the recent shift to targeting more proximal disease processes-e.g., huntingtin gene expression; a timely question given Roche's recent decision to take on the clinical development of a promising new drug candidate in Huntington's disease, IONIS-HTTRx.
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Affiliation(s)
- Melanie P Jensen
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Roger A Barker
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.,Cambridge Stem Cell Institute, Cambridge, UK
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12
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Abstract
Polyglutamine diseases are hereditary degenerative disorders of the nervous system that have remained, to this date, untreatable. Promisingly, investigation into their molecular etiology and the development of increasingly perfected tools have contributed to the design of novel strategies with therapeutic potential. Encouraging studies have explored gene therapy as a means to counteract cell demise and loss in this context. The current chapter addresses the two main focuses of research in the area: the characteristics of the systems used to deliver nucleic acids to cells and the molecular and cellular actions of the therapeutic agents. Vectors used in gene therapy have to satisfyingly reach the tissues and cell types of interest, while eliciting the lowest toxicity possible. Both viral and non-viral systems have been developed for the delivery of nucleic acids to the central nervous system, each with its respective advantages and shortcomings. Since each polyglutamine disease is caused by mutation of a single gene, many gene therapy strategies have tried to halt degeneration by silencing the corresponding protein products, usually recurring to RNA interference. The potential of small interfering RNAs, short hairpin RNAs and microRNAs has been investigated. Overexpression of protective genes has also been evaluated as a means of decreasing mutant protein toxicity and operate beneficial alterations. Recent gene editing tools promise yet other ways of interfering with the disease-causing genes, at the most upstream points possible. Results obtained in both cell and animal models encourage further delving into this type of therapeutic strategies and support the future use of gene therapy in the treatment of polyglutamine diseases.
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13
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Rinaldi C, Wood MJA. Antisense oligonucleotides: the next frontier for treatment of neurological disorders. Nat Rev Neurol 2017; 14:9-21. [PMID: 29192260 DOI: 10.1038/nrneurol.2017.148] [Citation(s) in RCA: 471] [Impact Index Per Article: 67.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Antisense oligonucleotides (ASOs) were first discovered to influence RNA processing and modulate protein expression over two decades ago; however, progress translating these agents into the clinic has been hampered by inadequate target engagement, insufficient biological activity, and off-target toxic effects. Over the years, novel chemical modifications of ASOs have been employed to address these issues. These modifications, in combination with elucidation of the mechanism of action of ASOs and improved clinical trial design, have provided momentum for the translation of ASO-based strategies into therapies. Many neurological conditions lack an effective treatment; however, as research progressively disentangles the pathogenic mechanisms of these diseases, they provide an ideal platform to test ASO-based strategies. This steady progress reached a pinnacle in the past few years with approvals of ASOs for the treatment of spinal muscular atrophy and Duchenne muscular dystrophy, which represent landmarks in a field in which disease-modifying therapies were virtually non-existent. With the rapid development of improved next-generation ASOs toward clinical application, this technology now holds the potential to have a dramatic effect on the treatment of many neurological conditions in the near future.
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Affiliation(s)
- Carlo Rinaldi
- Department of Physiology, Anatomy and Genetics, University of Oxford, Le Gros Clark Building, South Parks Road, Oxford OX1 3QX, UK
| | - Matthew J A Wood
- Department of Physiology, Anatomy and Genetics, University of Oxford, Le Gros Clark Building, South Parks Road, Oxford OX1 3QX, UK
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14
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Zaghloul EM, Gissberg O, Moreno PMD, Siggens L, Hällbrink M, Jørgensen AS, Ekwall K, Zain R, Wengel J, Lundin KE, Smith CIE. CTG repeat-targeting oligonucleotides for down-regulating Huntingtin expression. Nucleic Acids Res 2017; 45:5153-5169. [PMID: 28334749 PMCID: PMC5435994 DOI: 10.1093/nar/gkx111] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/06/2017] [Indexed: 12/12/2022] Open
Abstract
Huntington's disease (HD) is a fatal, neurodegenerative disorder in which patients suffer from mobility, psychological and cognitive impairments. Existing therapeutics are only symptomatic and do not significantly alter the disease progression or increase life expectancy. HD is caused by expansion of the CAG trinucleotide repeat region in exon 1 of the Huntingtin gene (HTT), leading to the formation of mutant HTT transcripts (muHTT). The toxic gain-of-function of muHTT protein is a major cause of the disease. In addition, it has been suggested that the muHTT transcript contributes to the toxicity. Thus, reduction of both muHTT mRNA and protein levels would ideally be the most useful therapeutic option. We herein present a novel strategy for HD treatment using oligonucleotides (ONs) directly targeting the HTT trinucleotide repeat DNA. A partial, but significant and potentially long-term, HTT knock-down of both mRNA and protein was successfully achieved. Diminished phosphorylation of HTT gene-associated RNA-polymerase II is demonstrated, suggestive of reduced transcription downstream the ON-targeted repeat. Different backbone chemistries were found to have a strong impact on the ON efficiency. We also successfully use different delivery vehicles as well as naked uptake of the ONs, demonstrating versatility and possibly providing insights for in vivo applications.
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Affiliation(s)
- Eman M Zaghloul
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, SE-141 86 Huddinge, Stockholm, Sweden.,Department of Pharmaceutics, Faculty of Pharmacy, Alexandria University, El-Khartoum square, Azareeta, 21 521 Alexandria, Egypt
| | - Olof Gissberg
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, SE-141 86 Huddinge, Stockholm, Sweden
| | - Pedro M D Moreno
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, SE-141 86 Huddinge, Stockholm, Sweden.,Instituto de Engenharia Biomédica, Universidade do Porto, 4200-135 Porto, Portugal.,Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
| | - Lee Siggens
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden, SE-141 86, Huddinge, Stockholm, Sweden
| | - Mattias Hällbrink
- Department of Neurochemistry, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Anna S Jørgensen
- Department of Physics and Chemistry, Nucleic Acid Centre University of Southern Denmark, DK-5230 Odense, Denmark
| | - Karl Ekwall
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden, SE-141 86, Huddinge, Stockholm, Sweden
| | - Rula Zain
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, SE-141 86 Huddinge, Stockholm, Sweden.,Department of Clinical Genetics, Centre for Rare Diseases, Karolinska University Hospital, SE-171 76 Stockholm, Sweden
| | - Jesper Wengel
- Department of Physics and Chemistry, Nucleic Acid Centre University of Southern Denmark, DK-5230 Odense, Denmark
| | - Karin E Lundin
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, SE-141 86 Huddinge, Stockholm, Sweden
| | - C I Edvard Smith
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, SE-141 86 Huddinge, Stockholm, Sweden
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15
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Abstract
Huntington's disease (HD) is an autosomal dominantly inherited neurodegenerative disease characterized by progressive motor, behavioral, and cognitive decline, ending in death. Despite the discovery of the underlying genetic mutation more than 20 years ago, treatment remains focused on symptomatic management. Chorea, the most recognizable symptom, responds to medication that reduces dopaminergic neurotransmission. Psychiatric symptoms such as depression and anxiety may also respond well to symptomatic therapies. Unfortunately, many other symptoms do not respond to current treatments. Furthermore, high-quality evidence for treatment of HD in general remains limited. To date, there has been minimal success with identifying a disease-modifying therapy based upon molecular models. However, one of the emerging gene silencing techniques may provide a breakthrough in treating this devastating disease.
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Affiliation(s)
- Kara J Wyant
- Department of Neurology, University of Michigan, 1324 Taubman Center, SPC 5322, 1500 E. Medical Center Drive, Ann Arbor, 48109-5322, USA.
| | - Andrew J Ridder
- Department of Neurology, University of Michigan, 1324 Taubman Center, SPC 5322, 1500 E. Medical Center Drive, Ann Arbor, 48109-5322, USA
| | - Praveen Dayalu
- Department of Neurology, University of Michigan, 1324 Taubman Center, SPC 5322, 1500 E. Medical Center Drive, Ann Arbor, 48109-5322, USA
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16
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Schoch KM, Miller TM. Antisense Oligonucleotides: Translation from Mouse Models to Human Neurodegenerative Diseases. Neuron 2017. [PMID: 28641106 DOI: 10.1016/j.neuron.2017.04.010] [Citation(s) in RCA: 199] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Multiple neurodegenerative diseases are characterized by single-protein dysfunction and aggregation. Treatment strategies for these diseases have often targeted downstream pathways to ameliorate consequences of protein dysfunction; however, targeting the source of that dysfunction, the affected protein itself, seems most judicious to achieve a highly effective therapeutic outcome. Antisense oligonucleotides (ASOs) are small sequences of DNA able to target RNA transcripts, resulting in reduced or modified protein expression. ASOs are ideal candidates for the treatment of neurodegenerative diseases, given numerous advancements made to their chemical modifications and delivery methods. Successes achieved in both animal models and human clinical trials have proven ASOs both safe and effective. With proper considerations in mind regarding the human applicability of ASOs, we anticipate ongoing in vivo research and clinical trial development of ASOs for the treatment of neurodegenerative diseases.
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Affiliation(s)
- Kathleen M Schoch
- Department of Neurology, Hope Center for Neurological Disorders, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Timothy M Miller
- Department of Neurology, Hope Center for Neurological Disorders, Washington University in St. Louis, St. Louis, MO 63110, USA.
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17
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Reverte M, Barvik I, Vasseur JJ, Smietana M. RNA-directed off/on switch of RNase H activity using boronic ester formation. Org Biomol Chem 2017; 15:8204-8210. [DOI: 10.1039/c7ob02145c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new concept to modulate RNase H activity is presented based on the boronic acid/boronate switch.
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Affiliation(s)
- Maëva Reverte
- Institut des Biomolecules Max Mousseron
- IBMM UMR 5247 CNRS
- Université de Montpellier
- ENSCM
- 34095 Montpellier
| | - Ivan Barvik
- Institute of Physics
- Faculty of Mathematics and Physics
- Charles University
- 121 16 Prague 2
- Czech Republic
| | - Jean-Jacques Vasseur
- Institut des Biomolecules Max Mousseron
- IBMM UMR 5247 CNRS
- Université de Montpellier
- ENSCM
- 34095 Montpellier
| | - Michael Smietana
- Institut des Biomolecules Max Mousseron
- IBMM UMR 5247 CNRS
- Université de Montpellier
- ENSCM
- 34095 Montpellier
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18
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Ross CA, Kronenbuerger M, Duan W, Margolis RL. Mechanisms underlying neurodegeneration in Huntington disease: applications to novel disease-modifying therapies. HANDBOOK OF CLINICAL NEUROLOGY 2017; 144:15-28. [PMID: 28947113 DOI: 10.1016/b978-0-12-801893-4.00002-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The CAG repeat expansion mutation that causes Huntington Disease (HD) was discovered more than 20 years ago, yet no treatment has yet been developed to stop the relentless course of the disease. Nonetheless, substantial progress has been made in understanding HD pathogenesis. We review insights that have been gleaned from HD genetics, metabolism, and pathology; HD mouse and cell models; the structure, function and post-translational modification of normal and mutant huntingtin (htt) protein; gene expression profiles in HD cells and tissue; the neurotoxicy of mutant htt RNA; and the expression of an antisense transcript from the HD locus. We conclude that rationale therapeutics for HD is within sight, though many questions remain to be answered.
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Affiliation(s)
- Christopher A Ross
- Division of Neurobiology, Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Departments of Neuroscience and Pharmacology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.
| | - Martin Kronenbuerger
- Division of Movement Disorders, Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Wenzhen Duan
- Division of Neurobiology, Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Translational Neurobiology Laboratory, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Russell L Margolis
- Division of Neurobiology, Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Translational Neurobiology Laboratory, Johns Hopkins University School of Medicine, Baltimore, MD, United States; Laboratory of Genetic Neurobiology and Johns Hopkins Schizophrenia Center, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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19
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Abstract
INTRODUCTION An inherited, chronic progressive, neurodegenerative disorder is Huntington's disease, characterized by motor, cognitive, and psychiatric symptoms. Predictive genetic testing allows earlier diagnosis and identification of gene carriers for Huntington's disease. These individuals are ideal candidates for testing of therapeutic interventions for disease modification. Areas covered: According to queries in Pubmed, Embase and clinical register databases, research and clinical studies emerge on symptomatic and neuroprotective therapies in Huntington's disease. This review discusses novel agents for symptomatic therapy and disease modification. They are currently in phase I and II of drug development Expert opinion: There are promising, safe and well tolerated compounds for amelioration of motor and neuropsychiatric symptoms, but their efficacy still needs to be proven in clinical trials. Deterioration of mutant huntingtin expression, antiapoptotic or cell death inhibition as disease modifying concepts was efficacious in models of Huntington's disease. However, the risk for clinical trial failures is high not only due to ineffectiveness of the tested agent. Negative study outcomes may also result from design misconceptions, underestimation of the heterogeneity of Huntington's disease, too short study durations and too small study cohorts.
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Affiliation(s)
- Thomas Müller
- a Department of Neurology , St. Joseph Hospital Berlin-Weißensee , Berlin , Germany
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20
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Rué L, Bañez-Coronel M, Creus-Muncunill J, Giralt A, Alcalá-Vida R, Mentxaka G, Kagerbauer B, Zomeño-Abellán MT, Aranda Z, Venturi V, Pérez-Navarro E, Estivill X, Martí E. Targeting CAG repeat RNAs reduces Huntington's disease phenotype independently of huntingtin levels. J Clin Invest 2016; 126:4319-4330. [PMID: 27721240 DOI: 10.1172/jci83185] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 09/08/2016] [Indexed: 12/11/2022] Open
Abstract
Huntington's disease (HD) is a polyglutamine disorder caused by a CAG expansion in the Huntingtin (HTT) gene exon 1. This expansion encodes a mutant protein whose abnormal function is traditionally associated with HD pathogenesis; however, recent evidence has also linked HD pathogenesis to RNA stable hairpins formed by the mutant HTT expansion. Here, we have shown that a locked nucleic acid-modified antisense oligonucleotide complementary to the CAG repeat (LNA-CTG) preferentially binds to mutant HTT without affecting HTT mRNA or protein levels. LNA-CTGs produced rapid and sustained improvement of motor deficits in an R6/2 mouse HD model that was paralleled by persistent binding of LNA-CTG to the expanded HTT exon 1 transgene. Motor improvement was accompanied by a pronounced recovery in the levels of several striatal neuronal markers severely impaired in R6/2 mice. Furthermore, in R6/2 mice, LNA-CTG blocked several pathogenic mechanisms caused by expanded CAG RNA, including small RNA toxicity and decreased Rn45s expression levels. These results suggest that LNA-CTGs promote neuroprotection by blocking the detrimental activity of CAG repeats within HTT mRNA. The present data emphasize the relevance of expanded CAG RNA to HD pathogenesis, indicate that inhibition of HTT expression is not required to reverse motor deficits, and further suggest a therapeutic potential for LNA-CTG in polyglutamine disorders.
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21
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Bhadra J, Pattanayak S, Sinha S. Synthesis of Morpholino Monomers, Chlorophosphoramidate Monomers, and Solid-Phase Synthesis of Short Morpholino Oligomers. ACTA ACUST UNITED AC 2015; 62:4.65.1-4.65.26. [PMID: 26380905 DOI: 10.1002/0471142700.nc0465s62] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Phosphorodiamidate morpholino oligomers (PMOs) are a highly capable class of synthetic antisense oligonucleotides that are used to study gene functions in in vitro and in vivo models. This unit describes the synthesis of exocyclic-amine-protected 7'-hydroxy and 7'-chlorophosphoramidate-activated morpholino monomers of A, T, G, and C, together with their incorporation into short PMO oligomers by solid-phase synthesis. Starting from ribonucleosides, the exocyclic-amine-protected 7'-hydroxy monomers are prepared following a modified Summerton protocol, which consists of a periodate cleavage/Schiff base formation/reduction cycle. The exocyclic amine protections are installed at a later stage (except G) to avoid the use of costly exocyclic-amine-protected counterparts that give control over protecting group manipulation. The 7'-hydroxy monomers with N-Trit/N-MMTr are then converted to the 7'-chlorophosphoramidate morpholino monomers in one step employing a combination of lithium bromide and DBU. These chlorophosphoramidate monomers are finally assembled by solid-support synthesis to obtain the short PMO oligomers.
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Affiliation(s)
- Jhuma Bhadra
- Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India.,These authors contributed equally
| | - Sankha Pattanayak
- Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India.,These authors contributed equally
| | - Surajit Sinha
- Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India
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22
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Lundin KE, Gissberg O, Smith CE. Oligonucleotide Therapies: The Past and the Present. Hum Gene Ther 2015; 26:475-85. [PMID: 26160334 PMCID: PMC4554547 DOI: 10.1089/hum.2015.070] [Citation(s) in RCA: 193] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 07/04/2015] [Indexed: 12/19/2022] Open
Abstract
In this review we address the development of oligonucleotide (ON) medicines from a historical perspective by listing the landmark discoveries in this field. The various biological processes that have been targeted and the corresponding ON interventions found in the literature are discussed together with brief updates on some of the more recent developments. Most ON therapies act through antisense mechanisms and are directed against various RNA species, as exemplified by gapmers, steric block ONs, antagomirs, small interfering RNAs (siRNAs), micro-RNA mimics, and splice switching ONs. However, ONs binding to Toll-like receptors and those forming aptamers have completely different modes of action. Similar to other novel medicines, the path to success has been lined with numerous failures, where different therapeutic ONs did not stand the test of time. Since the first ON drug was approved for clinical use in 1998, the therapeutic landscape has changed considerably, but many challenges remain until the expectations for this new form of medicine are met. However, there is room for cautious optimism.
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Affiliation(s)
- Karin E. Lundin
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Olof Gissberg
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - C.I. Edvard Smith
- Department of Laboratory Medicine, Clinical Research Center, Karolinska Institutet, Karolinska University Hospital Huddinge, Stockholm, Sweden
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23
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Progress and Prospects of Anti-HBV Gene Therapy Development. Int J Mol Sci 2015; 16:17589-610. [PMID: 26263978 PMCID: PMC4581210 DOI: 10.3390/ijms160817589] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Revised: 07/20/2015] [Accepted: 07/22/2015] [Indexed: 12/11/2022] Open
Abstract
Despite the availability of an effective vaccine against hepatitis B virus (HBV), chronic infection with the virus remains a major global health concern. Current drugs against HBV infection are limited by emergence of resistance and rarely achieve complete viral clearance. This has prompted vigorous research on developing better drugs against chronic HBV infection. Advances in understanding the life cycle of HBV and improvements in gene-disabling technologies have been impressive. This has led to development of better HBV infection models and discovery of new drug candidates. Ideally, a regimen against chronic HBV infection should completely eliminate all viral replicative intermediates, especially covalently closed circular DNA (cccDNA). For the past few decades, nucleic acid-based therapy has emerged as an attractive alternative that may result in complete clearance of HBV in infected patients. Several genetic anti-HBV strategies have been developed. The most studied approaches include the use of antisense oligonucleotides, ribozymes, RNA interference effectors and gene editing tools. This review will summarize recent developments and progress made in the use of gene therapy against HBV.
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24
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Sun X, Li PP, Zhu S, Cohen R, Marque LO, Ross CA, Pulst SM, Chan HYE, Margolis RL, Rudnicki DD. Nuclear retention of full-length HTT RNA is mediated by splicing factors MBNL1 and U2AF65. Sci Rep 2015. [PMID: 26218986 PMCID: PMC4517393 DOI: 10.1038/srep12521] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Huntington's disease (HD) is caused by a CAG repeat expansion in the huntingtin (HTT) gene. Recent evidence suggests that HD is a consequence of multimodal, non-mutually exclusive mechanisms of pathogenesis that involve both HTT protein- and HTT RNA-triggered mechanisms. Here we provide further evidence for the role of expanded HTT (expHTT) RNA in HD by demonstrating that a fragment of expHTT is cytotoxic in the absence of any translation and that the extent of cytotoxicity is similar to the cytotoxicity of an expHTT protein fragment encoded by a transcript of similar length and with a similar repeat size. In addition, full-length (FL) expHTT is retained in the nucleus. Overexpression of the splicing factor muscleblind-like 1 (MBNL1) increases nuclear retention of expHTT and decreases the expression of expHTT protein in the cytosol. The splicing and nuclear export factor U2AF65 has the opposite effect, decreasing expHTT nuclear retention and increasing expression of expHTT protein. This suggests that MBNL1 and U2AF65 play a role in nuclear export of expHTT RNA.
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Affiliation(s)
- Xin Sun
- 1] Department of Psychiatry and Behavioral Sciences, Division of Neurobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA [2] Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong, China
| | - Pan P Li
- Department of Psychiatry and Behavioral Sciences, Division of Neurobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Shanshan Zhu
- Department of Psychiatry and Behavioral Sciences, Division of Neurobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Rachael Cohen
- Department of Psychiatry and Behavioral Sciences, Division of Neurobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Leonard O Marque
- Department of Psychiatry and Behavioral Sciences, Division of Neurobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Christopher A Ross
- 1] Department of Psychiatry and Behavioral Sciences, Division of Neurobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA [2] Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA [3] Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA [4] Program of Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Stefan M Pulst
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - Ho Yin Edwin Chan
- Laboratory of Drosophila Research, School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, China
| | - Russell L Margolis
- 1] Department of Psychiatry and Behavioral Sciences, Division of Neurobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA [2] Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA [3] Program of Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Dobrila D Rudnicki
- 1] Department of Psychiatry and Behavioral Sciences, Division of Neurobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA [2] Program of Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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25
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Evers MM, Toonen LJ, van Roon-Mom WM. Antisense oligonucleotides in therapy for neurodegenerative disorders. Adv Drug Deliv Rev 2015; 87:90-103. [PMID: 25797014 DOI: 10.1016/j.addr.2015.03.008] [Citation(s) in RCA: 206] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 03/02/2015] [Accepted: 03/12/2015] [Indexed: 12/14/2022]
Abstract
Antisense oligonucleotides are synthetic single stranded strings of nucleic acids that bind to RNA and thereby alter or reduce expression of the target RNA. They can not only reduce expression of mutant proteins by breakdown of the targeted transcript, but also restore protein expression or modify proteins through interference with pre-mRNA splicing. There has been a recent revival of interest in the use of antisense oligonucleotides to treat several neurodegenerative disorders using different approaches to prevent disease onset or halt disease progression and the first clinical trials for spinal muscular atrophy and amyotrophic lateral sclerosis showing promising results. For these trials, intrathecal delivery is being used but direct infusion into the brain ventricles and several methods of passing the blood brain barrier after peripheral administration are also under investigation.
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26
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Skotte NH, Southwell AL, Østergaard ME, Carroll JB, Warby SC, Doty CN, Petoukhov E, Vaid K, Kordasiewicz H, Watt AT, Freier SM, Hung G, Seth PP, Bennett CF, Swayze EE, Hayden MR. Allele-specific suppression of mutant huntingtin using antisense oligonucleotides: providing a therapeutic option for all Huntington disease patients. PLoS One 2014; 9:e107434. [PMID: 25207939 PMCID: PMC4160241 DOI: 10.1371/journal.pone.0107434] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 08/11/2014] [Indexed: 01/10/2023] Open
Abstract
Huntington disease (HD) is an inherited, fatal neurodegenerative disorder caused by a CAG repeat expansion in the huntingtin gene. The mutant protein causes neuronal dysfunction and degeneration resulting in motor dysfunction, cognitive decline, and psychiatric disturbances. Currently, there is no disease altering treatment, and symptomatic therapy has limited benefit. The pathogenesis of HD is complicated and multiple pathways are compromised. Addressing the problem at its genetic root by suppressing mutant huntingtin expression is a promising therapeutic strategy for HD. We have developed and evaluated antisense oligonucleotides (ASOs) targeting single nucleotide polymorphisms that are significantly enriched on HD alleles (HD-SNPs). We describe our structure-activity relationship studies for ASO design and find that adjusting the SNP position within the gap, chemical modifications of the wings, and shortening the unmodified gap are critical for potent, specific, and well tolerated silencing of mutant huntingtin. Finally, we show that using two distinct ASO drugs targeting the two allelic variants of an HD-SNP could provide a therapeutic option for all persons with HD; allele-specifically for roughly half, and non-specifically for the remainder.
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Affiliation(s)
- Niels H. Skotte
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Amber L. Southwell
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Jeffrey B. Carroll
- Behavioral Neuroscience Program, Department of Psychology, Western Washington University, Bellingham, Washington, United States of America
| | - Simon C. Warby
- Center for Advanced Research in Sleep Medicine, Department of Psychiatry, University of Montréal, Montréal, Quebec, Canada
| | - Crystal N. Doty
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Eugenia Petoukhov
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kuljeet Vaid
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Andrew T. Watt
- ISIS Pharmaceuticals, Carlsbad, California, United States of America
| | - Susan M. Freier
- ISIS Pharmaceuticals, Carlsbad, California, United States of America
| | - Gene Hung
- ISIS Pharmaceuticals, Carlsbad, California, United States of America
| | - Punit P. Seth
- ISIS Pharmaceuticals, Carlsbad, California, United States of America
| | - C. Frank Bennett
- ISIS Pharmaceuticals, Carlsbad, California, United States of America
| | - Eric E. Swayze
- ISIS Pharmaceuticals, Carlsbad, California, United States of America
| | - Michael R. Hayden
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
- * E-mail:
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