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Aita R, Chen L, Verzi M. Evaluating Performance of IsoformSwitchAnalyzeR and mRNA Isoform Switching in Small Intestine Epithelial Differentiation. GASTRO HEP ADVANCES 2023; 2:1077-1081. [PMID: 38094226 PMCID: PMC10718563 DOI: 10.1016/j.gastha.2023.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 08/04/2023] [Indexed: 12/17/2023]
Affiliation(s)
- R. Aita
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers Cancer Institute of New Jersey, Rutgers Center for Lipid Research, New Jersey Institute for Food, Nutrition & Health, Division of Environmental & Population Health Biosciences, EOHSI, New Brunswick, New Jersey
| | - L. Chen
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers Cancer Institute of New Jersey, Rutgers Center for Lipid Research, New Jersey Institute for Food, Nutrition & Health, Division of Environmental & Population Health Biosciences, EOHSI, New Brunswick, New Jersey
- School of Life Science and Technology, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing, China
| | - M.P. Verzi
- Department of Genetics, Human Genetics Institute of New Jersey, Rutgers Cancer Institute of New Jersey, Rutgers Center for Lipid Research, New Jersey Institute for Food, Nutrition & Health, Division of Environmental & Population Health Biosciences, EOHSI, New Brunswick, New Jersey
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Péladeau C, Jasmin BJ. Identifying FDA-Approved Drugs that Upregulate Utrophin A as a Therapeutic Strategy for Duchenne Muscular Dystrophy. Methods Mol Biol 2023; 2587:495-510. [PMID: 36401046 DOI: 10.1007/978-1-0716-2772-3_26] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Duchenne muscular dystrophy (DMD) is a neuromuscular disease caused by mutations and deletions within the DMD gene, which result in a lack of dystrophin protein at the sarcolemma of skeletal muscle fibers. The absence of dystrophin fragilizes the sarcolemma and compromises its integrity during cycles of muscle contraction, which, progressively, leads to reductions in muscle mass and function. DMD is thus a progressive muscle-wasting disease that results in a loss of ambulation, cardiomyopathy , respiratory impairment, and death. Although there is presently no cure for DMD, recent advances have led to many promising treatments. One such approach entails increasing expression of a homologous protein to dystrophin, named utrophin A, which is endogenously expressed in both healthy and DMD muscle fibers. Upregulation of utrophin A all along the sarcolemma of DMD muscle fibers can, in part, compensate for the absence of dystrophin. Over the years, our laboratory has focused a significant portion of our efforts in identifying and characterizing drugs and small molecules for their ability to target utrophin A and cause its overexpression. As part of these efforts, we have recently developed a novel ELISA-based high-throughput drug screen, to identify FDA-approved drugs that increase the expression of utrophin A in muscle cells in culture as well as in dystrophic mice. Here, we describe our overall strategy to identify and characterize several FDA-approved drugs that upregulate utrophin A expression and provide details on all experimental approaches. Such strategy has the potential to lead to the rapid development of novel therapeutics for DMD.
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Affiliation(s)
- Christine Péladeau
- Department of Cellular and Molecular Medicine, and the Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Bernard J Jasmin
- Department of Cellular and Molecular Medicine, and the Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.
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PMO-based let-7c site blocking oligonucleotide (SBO) mediated utrophin upregulation in mdx mice, a therapeutic approach for Duchenne muscular dystrophy (DMD). Sci Rep 2020; 10:21492. [PMID: 33298994 PMCID: PMC7726560 DOI: 10.1038/s41598-020-76338-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 10/21/2020] [Indexed: 12/12/2022] Open
Abstract
Upregulation of utrophin, a dystrophin related protein, is considered a promising therapeutic approach for Duchenne muscular dystrophy (DMD). Utrophin expression is repressed at the post-transcriptional level by a set of miRNAs, among which let-7c is evolutionarily highly conserved. We designed PMO-based SBOs complementary to the let-7c binding site in UTRN 3′UTR, with the goal of inhibiting let-7c interaction with UTRN mRNA and thus upregulating utrophin. We used the C2C12UTRN5′luc3′ reporter cell line in which the 5′- and 3′-UTRs of human UTRN sequences flank luciferase, for reporter assays and the C2C12 cell line for utrophin western blots, to independently evaluate the site blocking efficiency of a series of let-7c PMOs in vitro. Treatment of one-month old mdx mice with the most effective let-7c PMO (i.e. S56) resulted in ca. two-fold higher utrophin protein expression in skeletal muscles and the improvement in dystrophic pathophysiology in mdx mice, in vivo. In summary, we show that PMO-based let-7c SBO has potential applicability for upregulating utrophin expression as a therapeutic approach for DMD.
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Péladeau C, Jasmin BJ. Targeting IRES-dependent translation as a novel approach for treating Duchenne muscular dystrophy. RNA Biol 2020; 18:1238-1251. [PMID: 33164678 DOI: 10.1080/15476286.2020.1847894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Internal-ribosomal entry sites (IRES) are translational elements that allow the initiation machinery to start protein synthesis via internal initiation. IRESs promote tissue-specific translation in stress conditions when conventional cap-dependent translation is inhibited. Since many IRES-containing mRNAs are relevant to diseases, this cellular mechanism is emerging as an attractive therapeutic target for pharmacological and genetic modulations. Indeed, there has been growing interest over the past years in determining the therapeutic potential of IRESs for several disease conditions such as cancer, neurodegeneration and neuromuscular diseases including Duchenne muscular dystrophy (DMD). IRESs relevant for DMD have been identified in several transcripts whose protein product results in functional improvements in dystrophic muscles. Together, these converging lines of evidence indicate that activation of IRES-mediated translation of relevant transcripts in DMD muscle represents a novel and appropriate therapeutic strategy for DMD that warrants further investigation, particularly to identify agents that can modulate their activity.
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Affiliation(s)
- Christine Péladeau
- Department of Cellular and Molecular Medicine, and the Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Bernard J Jasmin
- Department of Cellular and Molecular Medicine, and the Eric Poulin Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
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High-throughput identification of post-transcriptional utrophin up-regulators for Duchenne muscle dystrophy (DMD) therapy. Sci Rep 2020; 10:2132. [PMID: 32034254 PMCID: PMC7005813 DOI: 10.1038/s41598-020-58737-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 12/06/2019] [Indexed: 12/31/2022] Open
Abstract
Upregulation of endogenous utrophin offers great promise for treating DMD, as it can functionally compensate for the lack of dystrophin caused by DMD gene mutations, without the immunogenic concerns associated with delivering dystrophin. However, post-transcriptional repression mechanisms targeting the 5′ and 3′ untranslated regions (UTRs) of utrophin mRNA significantly limit the magnitude of utrophin upregulation achievable by promoter activation. Using a utrophin 5′3′UTR reporter assay, we performed a high-throughput screen (HTS) for small molecules capable of relieving utrophin post-transcriptional repression. We identified 27 hits that were ranked using a using an algorithm that we designed for hit prioritization that we call Hit to Lead Prioritization Score (H2LPS). The top 10 hits were validated using an orthogonal assay for endogenous utrophin expression. Evaluation of the top scoring hit, Trichostatin A (TSA), demonstrated utrophin upregulation and functional improvement in the mdx mouse model of DMD. TSA and the other small molecules identified here represent potential starting points for DMD drug discovery efforts.
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6
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Perkins KJ, Davies KE. Alternative utrophin mRNAs contribute to phenotypic differences between dystrophin-deficient mice and Duchenne muscular dystrophy. FEBS Lett 2018; 592:1856-1869. [PMID: 29772070 PMCID: PMC6032923 DOI: 10.1002/1873-3468.13099] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 05/01/2018] [Accepted: 05/07/2018] [Indexed: 12/31/2022]
Abstract
Duchenne muscular dystrophy (DMD) is a fatal disorder caused by absence of functional dystrophin protein. Compensation in dystrophin‐deficient (mdx) mice may be achieved by overexpression of its fetal paralogue, utrophin. Strategies to increase utrophin levels by stimulating promoter activity using small compounds are therefore a promising pharmacological approach. Here, we characterise similarities and differences existing within the mouse and human utrophin locus to assist in high‐throughput screening for potential utrophin modulator drugs. We identified five novel 5′‐utrophin isoforms (A′,B′,C,D and F) in adult and embryonic tissue. As the more efficient utrophin‐based response in mdx skeletal muscle appears to involve independent transcriptional activation of conserved, myogenic isoforms (A′ and F), elevating their paralogues in DMD patients is an encouraging therapeutic strategy.
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Affiliation(s)
- Kelly J Perkins
- Department of Physiology Anatomy and Genetics, University of Oxford, UK.,Sir William Dunn School of Pathology, University of Oxford, UK
| | - Kay E Davies
- Department of Physiology Anatomy and Genetics, University of Oxford, UK
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Péladeau C, Adam NJ, Jasmin BJ. Celecoxib treatment improves muscle function in mdx mice and increases utrophin A expression. FASEB J 2018; 32:5090-5103. [PMID: 29723037 DOI: 10.1096/fj.201800081r] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Duchenne muscular dystrophy (DMD) is a genetic and progressive neuromuscular disorder caused by mutations and deletions in the dystrophin gene. Although there is currently no cure, one promising treatment for DMD is aimed at increasing endogenous levels of utrophin A to compensate functionally for the lack of dystrophin. Recent studies from our laboratory revealed that heparin treatment of mdx mice activates p38 MAPK, leading to an upregulation of utrophin A expression and improvements in the dystrophic phenotype. Based on these findings, we sought to determine the effects of other potent p38 activators, including the cyclooxygenase (COX)-2 inhibitor celecoxib. In this study, we treated 6-wk-old mdx mice for 4 wk with celecoxib. Immunofluorescence analysis of celecoxib-treated mdx muscles revealed a fiber type switch from a fast to a slower phenotype along with beneficial effects on muscle fiber integrity. In agreement, celecoxib-treated mdx mice showed improved muscle strength. Celecoxib treatment also induced increases in utrophin A expression ranging from ∼1.5- to 2-fold in tibialis anterior diaphragm and heart muscles. Overall, these results highlight that activation of p38 in muscles can indeed lead to an attenuation of the dystrophic phenotype and reveal the potential role of celecoxib as a novel therapeutic agent for the treatment of DMD.-Péladeau, C., Adam, N. J., Jasmin, B. J. Celecoxib treatment improves muscle function in mdx mice and increases utrophin A expression.
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Affiliation(s)
- Christine Péladeau
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Nadine J Adam
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Bernard J Jasmin
- Department of Cellular and Molecular Medicine, Centre for Neuromuscular Disease, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
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8
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Bhat HF, Mir SS, Dar KB, Bhat ZF, Shah RA, Ganai NA. ABC of multifaceted dystrophin glycoprotein complex (DGC). J Cell Physiol 2017; 233:5142-5159. [DOI: 10.1002/jcp.25982] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 05/01/2017] [Indexed: 01/16/2023]
Affiliation(s)
- Hina F. Bhat
- Division of BiotechnologySher‐e‐Kashmir University of Agricultural Sciences and Technology of Kashmir SKUAST‐KShuhama, SrinagarJammu and KashmirIndia
| | - Saima S. Mir
- Department of BiotechnologyUniversity of KashmirHazratbal, SrinagarJammu and KashmirIndia
| | - Khalid B. Dar
- Department of BiochemistryUniversity of KashmirHazratbal, SrinagarJammu and KashmirIndia
| | - Zuhaib F. Bhat
- Division of Livestock Products and TechnologySher‐e‐Kashmir University of Agricultural Sciences and Technology of Jammu (SKUAST‐J), R.S. PoraJammuJammu and KashmirIndia
| | - Riaz A. Shah
- Division of BiotechnologySher‐e‐Kashmir University of Agricultural Sciences and Technology of Kashmir SKUAST‐KShuhama, SrinagarJammu and KashmirIndia
| | - Nazir A. Ganai
- Division of BiotechnologySher‐e‐Kashmir University of Agricultural Sciences and Technology of Kashmir SKUAST‐KShuhama, SrinagarJammu and KashmirIndia
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9
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Amirouche A, Tadesse H, Lunde JA, Bélanger G, Côté J, Jasmin BJ. Activation of p38 signaling increases utrophin A expression in skeletal muscle via the RNA-binding protein KSRP and inhibition of AU-rich element-mediated mRNA decay: implications for novel DMD therapeutics. Hum Mol Genet 2013; 22:3093-111. [PMID: 23575223 DOI: 10.1093/hmg/ddt165] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Several therapeutic approaches are currently being developed for Duchenne muscular dystrophy (DMD) including upregulating the levels of endogenous utrophin A in dystrophic fibers. Here, we examined the role of post-transcriptional mechanisms in controlling utrophin A expression in skeletal muscle. We show that activation of p38 leads to an increase in utrophin A independently of a transcriptional induction. Rather, p38 controls the levels of utrophin A mRNA by extending the half-life of transcripts via AU-rich elements (AREs). This mechanism critically depends on a decrease in the functional availability of KSRP, an RNA-binding protein known to promote decay of ARE-containing transcripts. In vitro and in vivo binding studies revealed that KSRP interacts with specific AREs located within the utrophin A 3' UTR. Electroporation experiments to knockdown KSRP led to an increase in utrophin A in wild-type and mdx mouse muscles. In pre-clinical studies, treatment of mdx mice with heparin, an activator of p38, causes a pronounced increase in utrophin A in diaphragm muscle fibers. Together, these studies identify a pathway that culminates in the post-transcriptional regulation of utrophin A through increases in mRNA stability. Furthermore, our results constitute proof-of-principle showing that pharmacological activation of p38 may prove beneficial as a novel therapeutic approach for DMD.
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Affiliation(s)
- Adel Amirouche
- Faculty of Medicine, Department of Cellular and Molecular Medicine and Centre for Neuromuscular Disease, University of Ottawa, ON, Canada K1H 8M5
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Moorwood C, Khurana TS. Duchenne muscular dystrophy drug discovery - the application of utrophin promoter activation screening. Expert Opin Drug Discov 2013; 8:569-81. [PMID: 23473647 DOI: 10.1517/17460441.2013.777040] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
INTRODUCTION Duchenne muscular dystrophy (DMD) is a devastating genetic muscle wasting disease caused by mutations in the DMD gene that in turn lead to an absence of dystrophin. Currently, there is no definitive therapy for DMD. Gene- and cell-based therapies designed to replace dystrophin have met some degree of success, as have strategies that seek to improve the dystrophic pathology independent of dystrophin. AREAS COVERED In this review the authors focus on utrophin promoter activation-based strategies and their implications on potential therapeutics for DMD. These strategies in common are designed to identify drugs/small molecules that can activate the utrophin promoter and would allow the functional substitution of dystrophin by upregulating utrophin expression in dystrophic muscle. The authors provide an overview of utrophin biology with a focus on regulation of the utrophin promoter and discuss current attempts in identifying utrophin promoter-activating molecules using high-throughput screening (HTS). EXPERT OPINION The characterisation of utrophin promoter regulatory mechanisms coupled with advances in HTS have allowed researchers to undertake screens and identify a number of promising lead compounds that may prove useful for DMD. In principle, these pharmacological compounds offer significant advantages from a translational viewpoint for developing DMD therapeutics.
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Affiliation(s)
- Catherine Moorwood
- University of Pennsylvania School of Dental Medicine, Department of Anatomy & Cell Biology, 438 Levy Research Building, 240 S. 40th Street, Philadelphia, PA 19104, USA
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Vianello S, Yu H, Voisin V, Haddad H, He X, Foutz AS, Sebrié C, Gillet B, Roulot M, Fougerousse F, Perronnet C, Vaillend C, Matecki S, Escolar D, Bossi L, Israël M, de la Porte S. Arginine butyrate: a therapeutic candidate for Duchenne muscular dystrophy. FASEB J 2013; 27:2256-69. [PMID: 23430975 DOI: 10.1096/fj.12-215723] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
As a strategy to treat Duchenne muscular dystrophy, we used arginine butyrate, which combines two pharmacological activities: nitric oxide pathway activation, and histone deacetylase inhibition. Continuous intraperitoneal administration to dystrophin-deficient mdx mice resulted in a near 2-fold increase in utrophin (protein homologous to dystrophin) in skeletal muscle, heart, and brain, accompanied by an improvement of the dystrophic phenotype in both adult and newborn mice (45 and 70% decrease in creatine kinase level, respectively; 14% increase in tidal volume, 30% decrease in necrotic area in limb and 23% increase in isometric force). Intermittent administration, as performed in clinical trials, was then used to reduce the frequency of injections and to improve safety. This also enhanced utrophin level around 2-fold (EC50=284 mg/ml) and alleviated the dystrophic phenotype (inverted grid and grip test performance near to wild-type values, creatine kinase level decreased by 50%). Skin biopsies were used to monitor treatment efficacy, instead of invasive muscle biopsies, and this could be done a few days after the start of treatment. A 2-fold increase in utrophin expression was also shown in cultured human myotubes. In vivo and in vitro experiments demonstrated that the drug combination acts synergistically. Together, these data constitute a proof of principle of the beneficial effects of arginine butyrate on muscular dystrophy.
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Affiliation(s)
- Sara Vianello
- Neurobiologie & Développement-Unité Propres de Recherche 3294, Centre National de la Recherche Scientifique, Institut de Neurobiologie Alfred Fessard-FRC2118, Gif sur Yvette, France
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Perronnet C, Chagneau C, Le Blanc P, Samson-Desvignes N, Mornet D, Laroche S, De La Porte S, Vaillend C. Upregulation of brain utrophin does not rescue behavioral alterations in dystrophin-deficient mice. Hum Mol Genet 2012; 21:2263-76. [PMID: 22343141 DOI: 10.1093/hmg/dds047] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Dystrophin, the protein responsible for X-linked Duchenne muscular dystrophy (DMD), is normally expressed in both muscle and brain, which explains that its loss also leads to cognitive deficits. The utrophin protein, an autosomal homolog, is a natural candidate for dystrophin replacement in patients. Pharmacological upregulation of endogenous utrophin improves muscle physiology in dystrophin-deficient mdx mice, and represents a potential therapeutic tool that has the advantage of allowing delivery to various organs following peripheral injections. Whether this could alleviate cognitive deficits, however, has not been explored. Here, we first investigated basal expression of all utrophins and dystrophins in the brain of mdx mice and found no evidence for spontaneous compensation by utrophins. Then, we show that systemic chronic, spaced injections of arginine butyrate (AB) alleviate muscle alterations and upregulate utrophin expression in the adult brain of mdx mice. AB selectively upregulated brain utrophin Up395, while reducing expression of Up113 and Up71. This, however, was not associated with a significant improvement of behavioral functions typically affected in mdx mice, which include exploration, emotional reactivity, spatial and fear memories. We suggest that AB did not overcome behavioral and cognitive dysfunctions because the regional and cellular expression of utrophins did not coincide with dystrophin expression in untreated mice, nor did it in AB-treated mice. While treatments based on the modulation of utrophin may alleviate DMD phenotypes in certain organs and tissues that coexpress dystrophins and utrophins in the same cells, improvement of cognitive functions would likely require acting on specific dystrophin-dependent mechanisms.
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Affiliation(s)
- Caroline Perronnet
- Univ Paris-Sud, Centre de Neurosciences Paris-Sud, UMR8195, Orsay F-91405, France
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Moorwood C, Lozynska O, Suri N, Napper AD, Diamond SL, Khurana TS. Drug discovery for Duchenne muscular dystrophy via utrophin promoter activation screening. PLoS One 2011; 6:e26169. [PMID: 22028826 PMCID: PMC3197614 DOI: 10.1371/journal.pone.0026169] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 09/21/2011] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Duchenne muscular dystrophy (DMD) is a devastating muscle wasting disease caused by mutations in dystrophin, a muscle cytoskeletal protein. Utrophin is a homologue of dystrophin that can functionally compensate for its absence when expressed at increased levels in the myofibre, as shown by studies in dystrophin-deficient mice. Utrophin upregulation is therefore a promising therapeutic approach for DMD. The use of a small, drug-like molecule to achieve utrophin upregulation offers obvious advantages in terms of delivery and bioavailability. Furthermore, much of the time and expense involved in the development of a new drug can be eliminated by screening molecules that are already approved for clinical use. METHODOLOGY/PRINCIPAL FINDINGS We developed and validated a cell-based, high-throughput screening assay for utrophin promoter activation, and used it to screen the Prestwick Chemical Library of marketed drugs and natural compounds. Initial screening produced 20 hit molecules, 14 of which exhibited dose-dependent activation of the utrophin promoter and were confirmed as hits. Independent validation demonstrated that one of these compounds, nabumetone, is able to upregulate endogenous utrophin mRNA and protein, in C2C12 muscle cells. CONCLUSIONS/SIGNIFICANCE We have developed a cell-based, high-throughput screening utrophin promoter assay. Using this assay, we identified and validated a utrophin promoter-activating drug, nabumetone, for which pharmacokinetics and safety in humans are already well described, and which represents a lead compound for utrophin upregulation as a therapy for DMD.
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Affiliation(s)
- Catherine Moorwood
- Department of Physiology and Pennsylvania Muscle Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Olga Lozynska
- Penn Center for Molecular Discovery, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Neha Suri
- Department of Physiology and Pennsylvania Muscle Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Andrew D. Napper
- Penn Center for Molecular Discovery, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Scott L. Diamond
- Penn Center for Molecular Discovery, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Tejvir S. Khurana
- Department of Physiology and Pennsylvania Muscle Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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Wang Q, Cao DH, Jin CL, Lin CK, Ma HW, Wu YY. A Method of Utrophin Up-Regulation through RNAi-Mediated Knockdown of the Transcription Factor EN1. J Int Med Res 2011; 39:161-71. [PMID: 21672318 DOI: 10.1177/147323001103900117] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The aim of this study was to induce up-regulation of the dystrophin-related gene UTRN that encodes the protein utrophin, to determine whether this could compensate for the lack of dystrophin function in Duchenne muscular dystrophy. The human UTRN promoter, which contains two putative binding sites for homeobox protein engrailed-1 (EN1), was analysed. It was found that EN1 binding site 2 in the UTRN gene promoter directly interacted with transcription factor EN1 in vitro. Chromatin immunoprecipitation assays of the EN1– UTRN promoter complex from rhabdomyosarcoma and HeLa cell lines confirmed that endogenous EN1 interacted with this region in vivo. The findings suggest that EN1 directly interacts with the UTRN promoter. Small interfering RNA was used to inhibit EN1 gene expression. Higher utrophin mRNA levels were observed in EN1-inhibited cells compared with controls. The increase in utrophin mRNA in rhabdomyosarcoma cells and HeLa cells may have resulted from inhibition of EN1 expression.
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Affiliation(s)
- Q Wang
- Senior Profession College, China Medical University, Shenyang, China
- Department of Medical Genetics, China Medical University, Shenyang, China
| | - D-H Cao
- Department of Laboratory Medicine, No. 202 Hospital of the People's Liberation Army, Shenyang, China
| | - C-L Jin
- Department of Medical Genetics, China Medical University, Shenyang, China
| | - C-K Lin
- Department of Medical Genetics, China Medical University, Shenyang, China
| | - H-W Ma
- Department of Paediatrics, Shengjing Hospital, China Medical University, Shenyang, China
| | - Y-Y Wu
- Department of Paediatrics, Shengjing Hospital, China Medical University, Shenyang, China
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15
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Dystrophins, utrophins, and associated scaffolding complexes: role in mammalian brain and implications for therapeutic strategies. J Biomed Biotechnol 2010; 2010:849426. [PMID: 20625423 PMCID: PMC2896903 DOI: 10.1155/2010/849426] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2009] [Accepted: 03/14/2010] [Indexed: 12/23/2022] Open
Abstract
Two decades of molecular, cellular, and functional studies considerably increased our understanding of dystrophins function and unveiled the complex etiology of the cognitive deficits in Duchenne muscular dystrophy (DMD), which involves altered expression of several dystrophin-gene products in brain. Dystrophins are normally part of critical cytoskeleton-associated membrane-bound molecular scaffolds involved in the clustering of receptors, ion channels, and signaling proteins that contribute to synapse physiology and blood-brain barrier function. The utrophin gene also drives brain expression of several paralogs proteins, which cellular expression and biological roles remain to be elucidated. Here we review the structural and functional properties of dystrophins and utrophins in brain, the consequences of dystrophins loss-of-function as revealed by numerous studies in mouse models of DMD, and we discuss future challenges and putative therapeutic strategies that may compensate for the cognitive impairment in DMD based on experimental manipulation of dystrophins and/or utrophins brain expression.
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