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Saito-Diaz K, Dietrich P, Wu HF, Sun X, Patel AJ, Wzientek CG, Prudden AR, Boons GJ, Chen S, Studer L, Xu B, Dragatsis I, Zeltner N. Genipin Crosslinks the Extracellular Matrix to Rescue Developmental and Degenerative Defects, and Accelerates Regeneration of Peripheral Neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.22.533831. [PMID: 36993570 PMCID: PMC10055431 DOI: 10.1101/2023.03.22.533831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
The peripheral nervous system (PNS) is essential for proper body function. A high percentage of the population suffer nerve degeneration or peripheral damage. For example, over 40% of patients with diabetes or undergoing chemotherapy develop peripheral neuropathies. Despite this, there are major gaps in the knowledge of human PNS development and therefore, there are no available treatments. Familial Dysautonomia (FD) is a devastating disorder that specifically affects the PNS making it an ideal model to study PNS dysfunction. FD is caused by a homozygous point mutation in ELP1 leading to developmental and degenerative defects in the sensory and autonomic lineages. We previously employed human pluripotent stem cells (hPSCs) to show that peripheral sensory neurons (SNs) are not generated efficiently and degenerate over time in FD. Here, we conducted a chemical screen to identify compounds able to rescue this SN differentiation inefficiency. We identified that genipin, a compound prescribed in Traditional Chinese Medicine for neurodegenerative disorders, restores neural crest and SN development in FD, both in the hPSC model and in a FD mouse model. Additionally, genipin prevented FD neuronal degeneration, suggesting that it could be offered to patients suffering from PNS neurodegenerative disorders. We found that genipin crosslinks the extracellular matrix, increases the stiffness of the ECM, reorganizes the actin cytoskeleton, and promotes transcription of YAP-dependent genes. Finally, we show that genipin enhances axon regeneration in an in vitro axotomy model in healthy sensory and sympathetic neurons (part of the PNS) and in prefrontal cortical neurons (part of the central nervous system, CNS). Our results suggest genipin can be used as a promising drug candidate for treatment of neurodevelopmental and neurodegenerative diseases, and as a enhancer of neuronal regeneration.
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Affiliation(s)
- Kenyi Saito-Diaz
- Center for Molecular Medicine, University of Georgia, Athens GA, USA
| | - Paula Dietrich
- Department of Physiology, The University of Tennessee, Health Science Center, Memphis, TN, USA
| | - Hsueh-Fu Wu
- Center for Molecular Medicine, University of Georgia, Athens GA, USA
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens GA, USA
| | - Xin Sun
- College of Engineering, University of Georgia, Athens GA, USA
| | | | | | | | - Geert-Jan Boons
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
- Department of Chemistry, University of Georgia, Athens, GA, USA
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, and Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands
| | - Shuibing Chen
- Department of Surgery and Department of Biochemistry at Weill Cornell Medical College, New York, NY, USA
- Center for Stem Cell Biology, Sloan Kettering Institute, New York, NY, USA
| | - Lorenz Studer
- Center for Stem Cell Biology, Sloan Kettering Institute, New York, NY, USA
- Department of Developmental Biology, Sloan Kettering Institute, New York, NY, USA
| | - Bingqian Xu
- College of Engineering, University of Georgia, Athens GA, USA
| | - Ioannis Dragatsis
- Department of Physiology, The University of Tennessee, Health Science Center, Memphis, TN, USA
| | - Nadja Zeltner
- Center for Molecular Medicine, University of Georgia, Athens GA, USA
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens GA, USA
- Department of Cellular Biology, University of Georgia, Athens GA, USA
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2
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Anderson SL, Fasih-Ahmad F, Evans AJ, Rubin BY. Carnosol, a diterpene present in rosemary, increases ELP1 levels in familial Dysautonomia (FD) patient-derived cells and healthy adults: a possible therapy for FD. Hum Mol Genet 2022; 31:3521-3538. [PMID: 35708500 DOI: 10.1093/hmg/ddac133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/12/2022] [Accepted: 06/01/2022] [Indexed: 11/13/2022] Open
Abstract
Recent research on Familial Dysautonomia (FD) has focused on the development of therapeutics that facilitate the production of the correctly spliced, exon 20-containing, transcript in cells and individuals bearing the splice-altering, FD-causing, mutation in the ELP1 gene. We report here the ability of carnosol, a diterpene present in plant species of the Lamiaceae family, including rosemary, to enhance the cellular presence of the correctly spliced ELP1 transcript in FD patient-derived fibroblasts by upregulating transcription of the ELP1 gene and correcting the aberrant splicing of the ELP1 transcript. Carnosol treatment also elevates the level of the RBM24 and RBM38 proteins., two multifunctional RNA binding proteins. Transfection-mediated expression of either of these RBMs facilitates the inclusion of exon 20 sequence into the transcript generated from a minigene bearing ELP1 genomic sequence containing the FD-causing mutation. Suppression of the carnosol-mediated induction of either of these RBMs, using targeting siRNAs, limited the carnosol-mediated inclusion of the ELP1 exon 20 sequence. Carnosol treatment of FD patient PBMCs facilitates the inclusion of exon 20 into the ELP1 transcript. Increased levels of the ELP1 and RBM38 transcripts and the alternative splicing of the SIRT2 transcript, a sentinel for exon 20 inclusion in the FD-derived ELP1 transcript, are observed in RNA isolated from whole blood of healthy adults following the ingestion of carnosol-containing rosemary extract. These findings and the excellent safety profile of rosemary together justify an expedited clinical study of the impact of carnosol on the FD patient population.
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Affiliation(s)
- Sylvia L Anderson
- Laboratory for Familial Dysautonomia Research, Department of Biological Sciences, Fordham University, Bronx, NY 10458, USA
| | - Faaria Fasih-Ahmad
- Laboratory for Familial Dysautonomia Research, Department of Biological Sciences, Fordham University, Bronx, NY 10458, USA
| | - Anthony J Evans
- Laboratory for Familial Dysautonomia Research, Department of Biological Sciences, Fordham University, Bronx, NY 10458, USA
| | - Berish Y Rubin
- Laboratory for Familial Dysautonomia Research, Department of Biological Sciences, Fordham University, Bronx, NY 10458, USA
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3
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Luthra R, Roy A. Role of medicinal plants against neurodegenerative diseases. Curr Pharm Biotechnol 2021; 23:123-139. [PMID: 33573549 DOI: 10.2174/1389201022666210211123539] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/12/2020] [Accepted: 11/23/2020] [Indexed: 11/22/2022]
Abstract
Diseases with a significant loss of neurons, structurally and functionally are termed as neurodegenerative diseases. Due to the present therapeutic interventions and progressive nature of diseases, a variety of side effects have risen up, thus leading the patients to go for an alternative medication. The role of medicinal plants in such cases has been beneficial because of their exhibition via different cellular and molecular mechanisms. Alleviation in inflammatory responses, suppression of the functionary aspect of pro-inflammatory cytokines like a tumor, improvement in antioxidative properties is among few neuroprotective mechanisms of traditional plants. Variation in transcription and transduction pathways play a vital role in the preventive measures of plants in such diseases. Neurodegenerative diseases are generally caused by depletion of proteins, oxidative and inflammatory stress, environmental changes and so on, with aging being the most important cause. Natural compounds can be used in order to treat neurodegenerative diseases Medicinal plants such as Ginseng, Withania somnifera, Bacopa monnieri, Ginkgo biloba, etc. are some of the medicinal plants for prevention of neurological symptoms. This review deals with the use of different medicinal plants for the prevention of neurodegenerative diseases.
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Affiliation(s)
- Ritika Luthra
- Department of Biotechnology, Delhi Technological University, Delhi. India
| | - Arpita Roy
- Department of Biotechnology, School of Engineering & Technology, Sharda University, Greater Noida. India
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Maková B, Mik V, Lišková B, Gonzalez G, Vítek D, Medvedíková M, Monfort B, Ručilová V, Kadlecová A, Khirsariya P, Gándara Barreiro Z, Havlíček L, Zatloukal M, Soural M, Paruch K, D'Autréaux B, Hajdúch M, Strnad M, Voller J. Cytoprotective activities of kinetin purine isosteres. Bioorg Med Chem 2021; 33:115993. [PMID: 33497938 DOI: 10.1016/j.bmc.2021.115993] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 12/31/2020] [Indexed: 01/23/2023]
Abstract
Kinetin (N6-furfuryladenine), a plant growth substance of the cytokinin family, has been shown to modulate aging and various age-related conditions in animal models. Here we report the synthesis of kinetin isosteres with the purine ring replaced by other bicyclic heterocycles, and the biological evaluation of their activity in several in vitro models related to neurodegenerative diseases. Our findings indicate that kinetin isosteres protect Friedreich́s ataxia patient-derived fibroblasts against glutathione depletion, protect neuron-like SH-SY5Y cells from glutamate-induced oxidative damage, and correct aberrant splicing of the ELP1 gene in fibroblasts derived from a familial dysautonomia patient. Although the mechanism of action of kinetin derivatives remains unclear, our data suggest that the cytoprotective activity of some purine isosteres is mediated by their ability to reduce oxidative stress. Further, the studies of permeation across artificial membrane and model gut and blood-brain barriers indicate that the compounds are orally available and can reach central nervous system. Overall, our data demonstrate that isosteric replacement of the kinetin purine scaffold is a fruitful strategy for improving known biological activities of kinetin and discovering novel therapeutic opportunities.
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Affiliation(s)
- Barbara Maková
- Department of Experimental Biology, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic
| | - Václav Mik
- Department of Experimental Biology, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic
| | - Barbora Lišková
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 3, Olomouc CZ-77515, Czech Republic
| | - Gabriel Gonzalez
- Department of Experimental Biology, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic; Department of Neurology, Palacký University Olomouc, Faculty of Medicine and Dentistry and University Hospital, Olomouc, Czech Republic
| | - Dominik Vítek
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 3, Olomouc CZ-77515, Czech Republic
| | - Martina Medvedíková
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 3, Olomouc CZ-77515, Czech Republic
| | - Beata Monfort
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Veronika Ručilová
- Department of Organic Chemistry, Faculty of Science, Palacký University, 17. listopadu 1192/12, Olomouc CZ-783-71, Czech Republic
| | - Alena Kadlecová
- Department of Experimental Biology, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic
| | - Prashant Khirsariya
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Zoila Gándara Barreiro
- Department of Experimental Biology, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic
| | - Libor Havlíček
- Isotope Laboratory, The Czech Academy of Science, Institute of Experimental Botany, Vídeňská 1083, Praha 4 CZ-14220, Czech Republic
| | - Marek Zatloukal
- Department of Chemical Biolology and Genetics, Centre of the Region Hana for Biotechnological and Agricultural Research, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic
| | - Miroslav Soural
- Department of Organic Chemistry, Faculty of Science, Palacký University, 17. listopadu 1192/12, Olomouc CZ-783-71, Czech Republic
| | - Kamil Paruch
- Department of Chemistry, CZ Openscreen, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Benoit D'Autréaux
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Marián Hajdúch
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 3, Olomouc CZ-77515, Czech Republic
| | - Miroslav Strnad
- Department of Experimental Biology, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic
| | - Jiří Voller
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská 3, Olomouc CZ-77515, Czech Republic; Laboratory of Growth Regulators, Palacký University & Institute of Experimental Botany AS CR, Šlechtitelů 27, Olomouc CZ-78371, Czech Republic.
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5
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Gebauer F, Schwarzl T, Valcárcel J, Hentze MW. RNA-binding proteins in human genetic disease. Nat Rev Genet 2020; 22:185-198. [PMID: 33235359 DOI: 10.1038/s41576-020-00302-y] [Citation(s) in RCA: 291] [Impact Index Per Article: 72.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/20/2020] [Indexed: 12/27/2022]
Abstract
RNA-binding proteins (RBPs) are critical effectors of gene expression, and as such their malfunction underlies the origin of many diseases. RBPs can recognize hundreds of transcripts and form extensive regulatory networks that help to maintain cell homeostasis. System-wide unbiased identification of RBPs has increased the number of recognized RBPs into the four-digit range and revealed new paradigms: from the prevalence of structurally disordered RNA-binding regions with roles in the formation of membraneless organelles to unsuspected and potentially pervasive connections between intermediary metabolism and RNA regulation. Together with an increasingly detailed understanding of molecular mechanisms of RBP function, these insights are facilitating the development of new therapies to treat malignancies. Here, we provide an overview of RBPs involved in human genetic disorders, both Mendelian and somatic, and discuss emerging aspects in the field with emphasis on molecular mechanisms of disease and therapeutic interventions.
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Affiliation(s)
- Fátima Gebauer
- Gene Regulation, Stem Cells and Cancer Program, Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Barcelona, Spain. .,University Pompeu Fabra (UPF), Barcelona, Spain.
| | - Thomas Schwarzl
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Juan Valcárcel
- Gene Regulation, Stem Cells and Cancer Program, Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, Barcelona, Spain.,University Pompeu Fabra (UPF), Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
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6
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Drissi I, Woods WA, Woods CG. Understanding the genetic basis of congenital insensitivity to pain. Br Med Bull 2020; 133:65-78. [PMID: 32219415 PMCID: PMC7227775 DOI: 10.1093/bmb/ldaa003] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/21/2020] [Accepted: 01/31/2020] [Indexed: 12/15/2022]
Abstract
INTRODUCTION OR BACKGROUND Congenital insensitivity to pain (CIP) is caused by extremely rare Mendelian genetic disorders. CIP individuals demonstrate the unexpectedly severe consequences of painlessness. Although only a small number of causative conditions and genes are known, most have led to profound insights into human nociception. CIP gene discovery is catalyzing the manufacture of completely new classes of analgesics, and these are needed as alternatives to synthetic highly potent opioids. SOURCES OF DATA Pubmed.gov peer-reviewed journal articles and reviews. AREAS OF AGREEMENT The importance of nerve growth factor-tropomyosin receptor kinase A (NGF-TRKA) signalling for nociceptor genesis and subsequent pain sensing.New analgesics can be generated from knowledge of the NGF-TRKA nociceptor pathway.Increased susceptibility to Staphylococcus aureus infection is a consequence of deficient NGF-TRKA signalling.Mutations in the voltage-gated sodium channels SCN9A and SCN11A can cause congenital painlessness, and in contradistinction, other mutations can cause episodic neuropathic pain. SCN9A/Nav1.7 is an analgesic target. SCN11A/Nav1.9 is unlikely to be an analgesic target.There are further Mendelian causes of painlessness to be discovered. AREAS OF CONTROVERSY Which NGF-TRKA intracellular signalling pathways operate in nociceptor development and which in post-natal pain sensing?Why have no clinically effective Nav1.7 antagonist been generated? SCN9A-CIP causes analgesia, at least in part, through endogenous opioids.Why do all CIP phenotypes involve a complete loss of all types of nociception? AREAS TIMELY FOR DEVELOPING RESEARCH PRDM12 as an analgesic target.Discovery of the function and analgesic potential of new CIP genes.Can NGF-TRKA be used in the treatment of S. aureus?
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Affiliation(s)
- Ichrak Drissi
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
| | - William Aidan Woods
- School of Medicine, David Weatherall building, University Road, Keele University, Staffordshire ST5 5BG, UK
| | - Christopher Geoffrey Woods
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, The Keith Peters Building, Hills Road, Cambridge CB2 0XY, UK
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7
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Bruun GH, Bang JMV, Christensen LL, Brøner S, Petersen USS, Guerra B, Grønning AGB, Doktor TK, Andresen BS. Blocking of an intronic splicing silencer completely rescues IKBKAP exon 20 splicing in familial dysautonomia patient cells. Nucleic Acids Res 2019; 46:7938-7952. [PMID: 29762696 PMCID: PMC6125618 DOI: 10.1093/nar/gky395] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Accepted: 04/30/2018] [Indexed: 12/22/2022] Open
Abstract
Familial dysautonomia (FD) is a severe genetic disorder causing sensory and autonomic dysfunction. It is predominantly caused by a c.2204+6T>C mutation in the IKBKAP gene. This mutation decreases the 5′ splice site strength of IKBKAP exon 20 leading to exon 20 skipping and decreased amounts of full-length IKAP protein. We identified a binding site for the splicing regulatory protein hnRNP A1 downstream of the IKBKAP exon 20 5′-splice site. We show that hnRNP A1 binds to this splicing regulatory element (SRE) and that two previously described inhibitory SREs inside IKBKAP exon 20 are also bound by hnRNP A1. Knockdown of hnRNP A1 in FD patient fibroblasts increases IKBKAP exon 20 inclusion demonstrating that hnRNP A1 is a negative regulator of IKBKAP exon 20 splicing. Furthermore, by mutating the SREs in an IKBKAP minigene we show that all three SREs cause hnRNP A1-mediated exon repression. We designed splice switching oligonucleotides (SSO) that blocks the intronic hnRNP A1 binding site, and demonstrate that this completely rescues splicing of IKBKAP exon 20 in FD patient fibroblasts and increases the amounts of IKAP protein. We propose that this may be developed into a potential new specific treatment of FD.
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Affiliation(s)
- Gitte H Bruun
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Jeanne M V Bang
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Lise L Christensen
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Sabrina Brøner
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Ulrika S S Petersen
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Barbara Guerra
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Alexander G B Grønning
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Thomas K Doktor
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Brage S Andresen
- Department of Biochemistry and Molecular Biology and The Villum Center for Bioanalytical Sciences, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
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8
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Yannai S, Zonszain J, Donyo M, Ast G. Combinatorial treatment increases IKAP levels in human cells generated from Familial Dysautonomia patients. PLoS One 2019; 14:e0211602. [PMID: 30889183 PMCID: PMC6424424 DOI: 10.1371/journal.pone.0211602] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Accepted: 03/07/2019] [Indexed: 02/06/2023] Open
Abstract
Familial Dysautonomia (FD) is an autosomal recessive congenital neuropathy that results from a point mutation at the 5' splice site of intron 20 in the IKBKAP gene. This mutation decreases production of the IKAP protein, and treatments that increase the level of the full-length IKBKAP transcript are likely to be of therapeutic value. We previously found that phosphatidylserine (PS), an FDA-approved food supplement, elevates IKAP levels in cells generated from FD patients. Here we demonstrate that combined treatment of cells generated from FD patients with PS and kinetin or PS and the histone deacetylase inhibitor trichostatin A (TSA) resulted in an additive elevation of IKAP compared to each drug alone. This indicates that the compounds influence different pathways. We also found that pridopidine enhances production of IKAP in cells generated from FD patients. Pridopidine has an additive effect on IKAP levels when used in combination with kinetin or TSA, but not with PS; suggesting that PS and pridopidine influence IKBKAP levels through the same mechanism. Indeed, we demonstrate that the effect of PS and pridopidine is through sigma-1 receptor-mediated activation of the BDNF signaling pathway. A combination treatment with any of these drugs with different mechanisms has potential to benefit FD patients.
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Affiliation(s)
- Sivan Yannai
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
| | - Jonathan Zonszain
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
| | - Maya Donyo
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
| | - Gil Ast
- Department of Human Molecular Genetics and Biochemestry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv-Yafo, Israel
- * E-mail:
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9
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Rubin BY, Anderson SL. IKBKAP/ELP1 gene mutations: mechanisms of familial dysautonomia and gene-targeting therapies. APPLICATION OF CLINICAL GENETICS 2017; 10:95-103. [PMID: 29290691 PMCID: PMC5735983 DOI: 10.2147/tacg.s129638] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The successful completion of the Human Genome Project led to the discovery of the molecular basis of thousands of genetic disorders. The identification of the mutations that cause familial dysautonomia (FD), an autosomal recessive disorder that impacts sensory and autonomic neurons, was aided by the release of the human DNA sequence. The identification and characterization of the genetic cause of FD have changed the natural history of this disease. Genetic testing programs, which were established shortly after the disease-causing mutations were identified, have almost completely eliminated the birth of children with this disorder. Characterization of the principal disease-causing mutation has led to the development of therapeutic modalities that ameliorate its effect, while the development of mouse models that recapitulate the impact of the mutation has allowed for the in-depth characterization of its impact on neuronal development and survival. The intense research focus on this disorder, while clearly benefiting the FD patient population, also serves as a model for the positive impact focused research efforts can have on the future of other genetic diseases. Here, we present the research advances and scientific breakthroughs that have changed and will continue to change the natural history of this centuries-old genetic disease.
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Affiliation(s)
- Berish Y Rubin
- Department of Biological Sciences, Fordham University, Bronx, NY, USA
| | - Sylvia L Anderson
- Department of Biological Sciences, Fordham University, Bronx, NY, USA
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10
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Ohe K, Yoshida M, Nakano-Kobayashi A, Hosokawa M, Sako Y, Sakuma M, Okuno Y, Usui T, Ninomiya K, Nojima T, Kataoka N, Hagiwara M. RBM24 promotes U1 snRNP recognition of the mutated 5' splice site in the IKBKAP gene of familial dysautonomia. RNA (NEW YORK, N.Y.) 2017; 23:1393-1403. [PMID: 28592461 PMCID: PMC5558909 DOI: 10.1261/rna.059428.116] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 05/25/2017] [Indexed: 06/07/2023]
Abstract
The 5' splice site mutation (IVS20+6T>C) of the inhibitor of κ light polypeptide gene enhancer in B cells, kinase complex-associated protein (IKBKAP) gene in familial dysautonomia (FD) is at the sixth intronic nucleotide of the 5' splice site. It is known to weaken U1 snRNP recognition and result in an aberrantly spliced mRNA product in neuronal tissue, but normally spliced mRNA in other tissues. Aberrantly spliced IKBKAP mRNA abrogates IKK complex-associated protein (IKAP)/elongator protein 1 (ELP1) expression and results in a defect of neuronal cell development in FD. To elucidate the tissue-dependent regulatory mechanism, we screened an expression library of major RNA-binding proteins (RBPs) with our mammalian dual-color splicing reporter system and identified RBM24 as a regulator. RBM24 functioned as a cryptic intronic splicing enhancer binding to an element (IVS20+13-29) downstream from the intronic 5' splice site mutation in the IKBKAP gene and promoted U1 snRNP recognition only to the mutated 5' splice site (and not the wild-type 5' splice site). Our results show that tissue-specific expression of RBM24 can explain the neuron-specific aberrant splicing of IKBKAP exon 20 in familial dysautonomia, and that ectopic expression of RBM24 in neuronal tissue could be a novel therapeutic target of the disease.
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Affiliation(s)
- Kenji Ohe
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
- Training Program of Leaders for Integrated Medical System for Fruitful Healthy-Longevity Society (LIMS), Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Mayumi Yoshida
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Akiko Nakano-Kobayashi
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Motoyasu Hosokawa
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yukiya Sako
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Maki Sakuma
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yukiko Okuno
- Medical Research Support Center, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Tomomi Usui
- Laboratory of Gene Expression, School of Biomedical Science, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Kensuke Ninomiya
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
| | - Takayuki Nojima
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
| | - Naoyuki Kataoka
- Laboratory for Malignancy Control Research, Medical Innovation Center, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8507, Japan
- Laboratory of Cell Regulation, Departments of Applied Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Masatoshi Hagiwara
- Department of Anatomy and Developmental Biology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan
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11
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Hervé M, Ibrahim EC. Proteasome inhibitors to alleviate aberrant IKBKAP mRNA splicing and low IKAP/hELP1 synthesis in familial dysautonomia. Neurobiol Dis 2017; 103:113-122. [PMID: 28404519 DOI: 10.1016/j.nbd.2017.04.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 03/23/2017] [Accepted: 04/05/2017] [Indexed: 12/27/2022] Open
Abstract
FD is a rare neurodegenerative disorder caused by a mutation of the IKBKAP gene, which induces low expression levels of the Elongator subunit IKAP/hELP1 protein. A rational strategy for FD treatment could be to identify drugs increasing IKAP/hELP1 expression levels by blocking protein degradation pathways such as the 26S proteasome. Proteasome inhibitors are promising molecules emerging in cancer treatment and could thus constitute an enticing pharmaceutical strategy for FD treatment. Therefore, we tested three proteasome inhibitors on FD human olfactory ecto-mesenchymal stem cells (hOE-MSCs): two approved by the Food and Drug Administration (FDA) and European Medicines Agency (EMA), bortezomib and carfilzomib, as well as epoxomicin. Although all 3 inhibitors demonstrated activity in correcting IKBKAP mRNA aberrant splicing, carfilzomib was superior in enhancing IKAP/hELP1 quantity. Moreover, we observed a synergistic effect of suboptimal doses of carfilzomib on kinetin in improving IKBKAP isoforms ratio and IKAP/hELP1 expression levels allowing to counterbalance carfilzomib toxicity. Finally, we identified several dysregulated miRNAs after carfilzomib treatment that target proteasome-associated mRNAs and determined that IKAP/hELP1 deficiency in FD pathology is correlated to an overactivity of the 26S proteasome. Altogether, these results reinforce the rationale for using chemical compounds inhibiting the 26S proteasome as an innovative option for FD and a promising therapeutic pathway for many other neurodegenerative diseases.
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Affiliation(s)
- Mylène Hervé
- Aix-Marseille Univ, CNRS, CRN2M, 13344 Marseille Cedex 15, France
| | - El Chérif Ibrahim
- Aix-Marseille Univ, CNRS, CRN2M, 13344 Marseille Cedex 15, France; Aix-Marseille Univ, CNRS, INT, Inst Neurosci Timone, 13385 Marseille Cedex 5, France.
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12
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Kataoka N. Modulation of aberrant splicing in human RNA diseases by chemical compounds. Hum Genet 2017; 136:1237-1245. [PMID: 28364159 DOI: 10.1007/s00439-017-1789-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 03/25/2017] [Indexed: 01/09/2023]
Abstract
Pre-mRNA splicing is an essential step for gene expression in higher eukaryotes. Alternative splicing contributes to diversity of the expressed proteins from the limited number of genes. Disruption of splicing regulation often results in hereditary and sporadic diseases called as 'RNA diseases'. Modulation of splicing by small chemical compounds and nucleic acids has been tried to target aberrant splicing in those diseases. Several RNA diseases and splicing-target therapeutic approaches will be briefly introduced in this review. Accumulating knowledge about molecular mechanism of aberrant splicing and their correction by chemical compounds is important not only for RNA biologists, but also for clinicians who desire therapies for those diseases.
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Affiliation(s)
- Naoyuki Kataoka
- Laboratory of Cell Regulation, Departments of Applied Animal Sciences and Applied Biological Chemistry, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan.
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13
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Norcliffe-Kaufmann L, Slaugenhaupt SA, Kaufmann H. Familial dysautonomia: History, genotype, phenotype and translational research. Prog Neurobiol 2016; 152:131-148. [PMID: 27317387 DOI: 10.1016/j.pneurobio.2016.06.003] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 06/10/2016] [Accepted: 06/11/2016] [Indexed: 01/30/2023]
Abstract
Familial dysautonomia (FD) is a rare neurological disorder caused by a splice mutation in the IKBKAP gene. The mutation arose in the 1500s within the small Jewish founder population in Eastern Europe and became prevalent during the period of rapid population expansion within the Pale of Settlement. The carrier rate is 1:32 in Jews descending from this region. The mutation results in a tissue-specific deficiency in IKAP, a protein involved in the development and survival of neurons. Patients homozygous for the mutations are born with multiple lesions affecting mostly sensory (afferent) fibers, which leads to widespread organ dysfunction and increased mortality. Neurodegenerative features of the disease include progressive optic atrophy and worsening gait ataxia. Here we review the progress made in the last decade to better understand the genotype and phenotype. We also discuss the challenges of conducting controlled clinical trials in this rare medically fragile population. Meanwhile, the search for better treatments as well as a neuroprotective agent is ongoing.
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Affiliation(s)
| | - Susan A Slaugenhaupt
- Center for Human Genetic Research, Massachusetts General Hospital Research Institute and Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Horacio Kaufmann
- Department of Neurology, New York University School of Medicine, New York, NY, USA.
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14
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Cheishvili D, Maayan C, Holzer N, Tsenter J, Lax E, Petropoulos S, Razin A. Tocotrienol Treatment in Familial Dysautonomia: Open-Label Pilot Study. J Mol Neurosci 2016; 59:382-91. [PMID: 27129499 DOI: 10.1007/s12031-016-0760-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 04/22/2016] [Indexed: 10/21/2022]
Abstract
Familial dysautonomia (FD) is an autosomal recessive congenital neuropathy, primarily presented in Ashkenazi Jews. The most common mutation in FD patients results from a single base pair substitution of an intronic splice site in the IKBKAP gene which disrupts normal mRNA splicing and leads to tissue-specific reduction of IKBKAP protein (IKAP). To date, treatment of FD patients remains preventative, symptomatic and supportive. Based on previous in vitro evidence that tocotrienols, members of the vitamin E family, upregulate transcription of the IKBKAP gene, we aimed to investigate whether a similar effects was observed in vivo. In the current study, we assessed the effects of tocotrienol treatment on FD patients' symptoms and IKBKAP expression in white blood cells. The initial daily doses of 50 or 100 mg tocotrienol, doubled after 3 months, was administered to 32 FD patients. Twenty-eight FD patients completed the 6-month study. The first 3 months of tocotrienol treatment was associated with a significant increase in IKBKAP expression level in FD patients' blood. Despite doubling the dose after the initial 3 months of treatment, IKBKAP expression level returned to baseline by the end of the 6-month treatment. Clinical improvement was noted in the reported clinical questionnaire (with regard to dizziness, bloching, sweating, number of pneumonia, cough episodes, and walking stability), however, no significant effect was observed in any clinical measurements (weight, height, oxygen saturation, blood pressure, tear production, histamine test, vibration threshold test, nerve conduction, and heart rate variability) following Tocotrienol treatment. In conclusion, tocotrienol treatment appears significantly beneficial by clinical evaluation for some FD patients in a few clinical parameters; however it was not significant by clinical measurements. This open-label study shows the complexity of effect of tocotrienol treatment on FD patients' clinical outcomes and on IKBKAP expression level compared to in vitro results. A longitudinal study with an increased sample size is required in the future to better understand tocotrienol affect on FD patients.
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Affiliation(s)
- David Cheishvili
- The Israeli Familial Dysautonomia Center at the Department of Pediatrics, Hadassah University Hospital Mount Scopus, Hebrew University-Hadassah Medical School, Jerusalem, Israel. .,Department of Rehabilitation, Hadassah University Hospital Mount Scopus, Hebrew University-Hadassah Medical School, Jerusalem, Israel. .,Department of Pharmacology & Therapeutics, McGill University Medical School, 3655 Promenade Sir William Osler, Montreal, QC, H3G 1Y6, Canada. .,Department of Developmental Biology and Cancer Research, The Hebrew University, Hadassah School of Medicine, Jerusalem, Israel.
| | - Channa Maayan
- The Israeli Familial Dysautonomia Center at the Department of Pediatrics, Hadassah University Hospital Mount Scopus, Hebrew University-Hadassah Medical School, Jerusalem, Israel.,Department of Rehabilitation, Hadassah University Hospital Mount Scopus, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Naama Holzer
- The Israeli Familial Dysautonomia Center at the Department of Pediatrics, Hadassah University Hospital Mount Scopus, Hebrew University-Hadassah Medical School, Jerusalem, Israel.,Department of Rehabilitation, Hadassah University Hospital Mount Scopus, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Jeanna Tsenter
- Department of Developmental Biology and Cancer Research, The Hebrew University, Hadassah School of Medicine, Jerusalem, Israel
| | - Elad Lax
- Department of Pharmacology & Therapeutics, McGill University Medical School, 3655 Promenade Sir William Osler, Montreal, QC, H3G 1Y6, Canada
| | - Sophie Petropoulos
- Department of Pharmacology & Therapeutics, McGill University Medical School, 3655 Promenade Sir William Osler, Montreal, QC, H3G 1Y6, Canada
| | - Aharon Razin
- Department of Developmental Biology and Cancer Research, The Hebrew University, Hadassah School of Medicine, Jerusalem, Israel
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15
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Igreja S, Clarke LA, Botelho HM, Marques L, Amaral MD. Correction of a Cystic Fibrosis Splicing Mutation by Antisense Oligonucleotides. Hum Mutat 2015; 37:209-15. [PMID: 26553470 DOI: 10.1002/humu.22931] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 10/29/2015] [Indexed: 11/06/2022]
Abstract
Cystic fibrosis (CF), the most common life-threatening genetic disease in Caucasians, is caused by ∼2,000 different mutations in the CF transmembrane conductance regulator (CFTR) gene. A significant fraction of these (∼13%) affect pre-mRNA splicing for which novel therapies have been somewhat neglected. We have previously described the effect of the CFTR splicing mutation c.2657+5G>A in IVS16, showing that it originates transcripts lacking exon 16 as well as wild-type transcripts. Here, we tested an RNA-based antisense oligonucleotide (AON) strategy to correct the aberrant splicing caused by this mutation. Two AONs (AON1/2) complementary to the pre-mRNA IVS16 mutant region were designed and their effect on splicing was assessed at the RNA and protein levels, on intracellular protein localization and function. To this end, we used the 2657+5G>A mutant CFTR minigene stably expressed in HEK293 Flp-In cells that express a single copy of the transgene. RNA data from AON1-treated mutant cells show that exon 16 inclusion was almost completely restored (to 95%), also resulting in increased levels of correctly localized CFTR protein at the plasma membrane (PM) and with increased function. A novel two-color CFTR splicing reporter minigene developed here allowed the quantitative monitoring of splicing by automated microscopy localization of CFTR at the PM. The AON strategy is thus a promising therapeutic approach for the specific correction of alternative splicing.
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Affiliation(s)
- Susana Igreja
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Luka A Clarke
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Hugo M Botelho
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Luís Marques
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Margarida D Amaral
- University of Lisboa, Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, Lisboa, Portugal
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16
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Ohe K, Hagiwara M. Modulation of alternative splicing with chemical compounds in new therapeutics for human diseases. ACS Chem Biol 2015; 10:914-24. [PMID: 25560473 DOI: 10.1021/cb500697f] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Alternative splicing is a critical step where a limited number of human genes generate a complex and diverse proteome. Various diseases, including inherited diseases with abnormalities in the "genome code," have been found to result in an aberrant mis-spliced "transcript code" with correlation to the resulting phenotype. Chemical compound-based and nucleic acid-based strategies are trying to target this mis-spliced "transcript code". We will briefly mention about how to obtain splicing-modifying-compounds by high-throughput screening and overview of what is known about compounds that modify splicing pathways. The main focus will be on RNA-binding protein kinase inhibitors. In the main text, we will refer to diseases where splicing-modifying-compounds have been intensively investigated, with comparison to nucleic acid-based strategies. The information on their involvement in mis-splicing as well as nonsplicing events will be helpful in finding better compounds with less off-target effects for future implications in mis-splicing therapy.
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Affiliation(s)
- Kenji Ohe
- †Department of Anatomy and Developmental Biology and ‡Training Program of Leaders for Integrated Medical System for Fruitful Healthy-Longevity Society (LIMS), Kyoto University Graduate School of Medicine, Kyoto 606-8315, Japan
| | - Masatoshi Hagiwara
- †Department of Anatomy and Developmental Biology and ‡Training Program of Leaders for Integrated Medical System for Fruitful Healthy-Longevity Society (LIMS), Kyoto University Graduate School of Medicine, Kyoto 606-8315, Japan
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17
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Rectifying RNA splicing errors in hereditary neurodegenerative disease. Proc Natl Acad Sci U S A 2015; 112:2637-8. [PMID: 25691745 DOI: 10.1073/pnas.1500976112] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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18
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Rectifier of aberrant mRNA splicing recovers tRNA modification in familial dysautonomia. Proc Natl Acad Sci U S A 2015; 112:2764-9. [PMID: 25675486 DOI: 10.1073/pnas.1415525112] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Familial dysautonomia (FD), a hereditary sensory and autonomic neuropathy, is caused by missplicing of exon 20, resulting from an intronic mutation in the inhibitor of kappa light polypeptide gene enhancer in B cells, kinase complex-associated protein (IKBKAP) gene encoding IKK complex-associated protein (IKAP)/elongator protein 1 (ELP1). A newly established splicing reporter assay allowed us to visualize pathogenic splicing in cells and to screen small chemicals for the ability to correct the aberrant splicing of IKBKAP. Using this splicing reporter, we screened our chemical libraries and identified a compound, rectifier of aberrant splicing (RECTAS), that rectifies the aberrant IKBKAP splicing in cells from patients with FD. Here, we found that the levels of modified uridine at the wobble position in cytoplasmic tRNAs are reduced in cells from patients with FD and that treatment with RECTAS increases the expression of IKAP and recovers the tRNA modifications. These findings suggest that the missplicing of IKBKAP results in reduced tRNA modifications in patients with FD and that RECTAS is a promising therapeutic drug candidate for FD.
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19
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Finley J. Alteration of splice site selection in the LMNA gene and inhibition of progerin production via AMPK activation. Med Hypotheses 2014; 83:580-7. [PMID: 25216752 DOI: 10.1016/j.mehy.2014.08.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 08/11/2014] [Indexed: 02/06/2023]
Abstract
Hutchinson-Gilford Progeria Syndrome (HGPS) is a rare genetic condition characterized by an accelerated aging phenotype and an average life span of 13years. Patients typically exhibit extensive pathophysiological vascular alterations, eventually resulting in death from stroke or myocardial infarction. A silent point mutation at position 1824 (C1824T) of the LMNA gene, generating a truncated form of lamin A (progerin), has been shown to be the cause of most cases of HGPS. Interestingly, this mutation induces the use of an internal 5' cryptic splice site within exon 11 of the LMNA pre-mRNA, leading to the generation of progerin via aberrant alternative splicing. The serine-arginine rich splicing factor 1 (SRSF1 or ASF/SF2) has been shown to function as an oncoprotein and is upregulated in many cancers and other age-related disorders. Indeed, SRSF1 inhibition results in a splicing ratio in the LMNA pre-mRNA favoring lamin A production over that of progerin. It is our hypothesis that activation of AMP-activated protein kinase (AMPK), a master regulator of cellular metabolism, may lead to a reduction in SRSF1 and thus a decrease in the use of the LMNA 5' cryptic splice site in exon 11 through upregulation of p32, a splicing factor-associated protein and putative mitochondrial chaperone that has been shown to inhibit SRSF1 and enhance mitochondrial DNA (mtDNA) replication and oxidative phosphorylation. AMPK activation by currently available compounds such as metformin, resveratrol, and berberine may thus have wide-ranging implications for disorders associated with increased production and accumulation of progerin.
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20
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Naturally occurring plant polyphenols as potential therapies for inherited neuromuscular diseases. Future Med Chem 2014; 5:2091-101. [PMID: 24215348 DOI: 10.4155/fmc.13.165] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
There are several lines of laboratory-based evidence emerging to suggest that purified polyphenol compounds such as resveratrol, found naturally in red grapes, epigallocatechin galate from green tea and curcumin from turmeric, might be useful for the treatment of various inherited neuromuscular diseases, including spinal muscular atrophy, Duchenne muscular dystrophy and Charcot-Marie-Tooth disease. Here, we critically examine the scientific evidence related to the known molecular effects that these polyphenols have on different models of inherited neuromuscular disease, with particular attention to problems with the validity of in vitro evidence. We also present proteomic evidence that polyphenols have in vitro effects on cells related to metal ion chelation in cell-culture media. Although their precise mechanisms of action remain somewhat elusive, polyphenols could be an attractive approach to therapy for inherited neuromuscular disease, especially since they may be safer to use on young children, compared with some of the other drug candidates.
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21
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Botman O, Wyns C. Induced pluripotent stem cell potential in medicine, specifically focused on reproductive medicine. Front Surg 2014; 1:5. [PMID: 25671222 PMCID: PMC4313692 DOI: 10.3389/fsurg.2014.00005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 03/05/2014] [Indexed: 01/15/2023] Open
Abstract
Since 2006, several laboratories have proved that somatic cells can be reprogramed into induced pluripotent stem cells (iPSCs). iPSCs have enormous potential in stem cell biology as they can give rise to numerous cell lineages, including the three germ layers. In this review, we discuss past and recent advances in human iPSCs used for modeling diseases in vitro, screening drugs to test new treatments, and autologous cell and tissue regenerative therapies, with a special focus on reproductive medicine applications. While this latter field of research is still in its infancy, it holds great promise for investigating germ cell development and studying the genetic and physiopathological mechanisms of infertility. A major cause of infertility is the absence of germ cells in the testes, mainly due to genetic background or as a consequence of gonadotoxic treatments. For these patients, no effective fertility restoration strategy has so far been identified. The derivation of germ cells from iPSCs represents an alternative source of stem cells able to differentiate into spermatozoa. Lessons learned from animal models as well as studies on human iPSCs for reproductive purposes are reviewed.
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Affiliation(s)
- Olivier Botman
- Gynecology Unit, Medical School, Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain , Brussels , Belgium
| | - Christine Wyns
- Gynecology Unit, Medical School, Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain , Brussels , Belgium ; Cliniques Universitaires Saint-Luc, Université Catholique de Louvain , Brussels , Belgium
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22
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Torres AG, Batlle E, Ribas de Pouplana L. Role of tRNA modifications in human diseases. Trends Mol Med 2014; 20:306-14. [PMID: 24581449 DOI: 10.1016/j.molmed.2014.01.008] [Citation(s) in RCA: 295] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 01/17/2014] [Accepted: 01/23/2014] [Indexed: 12/22/2022]
Abstract
Transfer RNAs (tRNAs) are key for efficient and accurate protein translation. To be fully active, tRNAs need to be heavily modified post-transcriptionally. Growing evidence indicates that tRNA modifications and the enzymes catalyzing such modifications may play important roles in complex human pathologies. Here, we have compiled current knowledge that directly link tRNA modifications to human diseases such as cancer, type 2 diabetes (T2D), neurological disorders, and mitochondrial-linked disorders. The molecular mechanisms behind these connections remain, for the most part, unknown. As we progress towards the understanding of the roles played by hypomodified tRNAs in human disease, novel areas of therapeutic intervention may be discovered.
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Affiliation(s)
- Adrian Gabriel Torres
- Institute for Research in Biomedicine (IRB), Parc Cientific de Barcelona, 08028 Catalunya, Spain
| | - Eduard Batlle
- Institute for Research in Biomedicine (IRB), Parc Cientific de Barcelona, 08028 Catalunya, Spain; Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, 08010 Catalunya, Spain
| | - Lluis Ribas de Pouplana
- Institute for Research in Biomedicine (IRB), Parc Cientific de Barcelona, 08028 Catalunya, Spain; Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, 08010 Catalunya, Spain.
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23
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Sarin LP, Leidel SA. Modify or die?--RNA modification defects in metazoans. RNA Biol 2014; 11:1555-67. [PMID: 25692999 PMCID: PMC4615230 DOI: 10.4161/15476286.2014.992279] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 11/06/2014] [Accepted: 11/10/2014] [Indexed: 12/21/2022] Open
Abstract
Chemical RNA modifications are present in all kingdoms of life and many of these post-transcriptional modifications are conserved throughout evolution. However, most of the research has been performed on single cell organisms, whereas little is known about how RNA modifications contribute to the development of metazoans. In recent years, the identification of RNA modification genes in genome wide association studies (GWAS) has sparked new interest in previously neglected genes. In this review, we summarize recent findings that connect RNA modification defects and phenotypes in higher eukaryotes. Furthermore, we discuss the implications of aberrant tRNA modification in various human diseases including metabolic defects, mitochondrial dysfunctions, neurological disorders, and cancer. As the molecular mechanisms of these diseases are being elucidated, we will gain first insights into the functions of RNA modifications in higher eukaryotes and finally understand their roles during development.
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MESH Headings
- Amyotrophic Lateral Sclerosis/genetics
- Amyotrophic Lateral Sclerosis/metabolism
- Amyotrophic Lateral Sclerosis/pathology
- Animals
- Dysautonomia, Familial/genetics
- Dysautonomia, Familial/metabolism
- Dysautonomia, Familial/pathology
- Epilepsy, Rolandic/genetics
- Epilepsy, Rolandic/metabolism
- Epilepsy, Rolandic/pathology
- Genome-Wide Association Study
- Humans
- Intellectual Disability/genetics
- Intellectual Disability/metabolism
- Intellectual Disability/pathology
- Mutation
- Neoplasms/genetics
- Neoplasms/metabolism
- Neoplasms/pathology
- Nucleic Acid Conformation
- Phenotype
- RNA/genetics
- RNA/metabolism
- RNA Processing, Post-Transcriptional
- RNA, Mitochondrial
- RNA, Transfer/genetics
- RNA, Transfer/metabolism
- tRNA Methyltransferases/genetics
- tRNA Methyltransferases/metabolism
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Affiliation(s)
- L Peter Sarin
- Max Planck Institute for Molecular Biomedicine; Münster, Germany
| | - Sebastian A Leidel
- Max Planck Institute for Molecular Biomedicine; Münster, Germany
- Faculty of Medicine; University of Münster; Münster, Germany
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24
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Abruzzo PM, Marini M, Bolotta A, Malisardi G, Manfredini S, Ghezzo A, Pini A, Tasco G, Casadio R. Frataxin mRNA isoforms in FRDA patients and normal subjects: effect of tocotrienol supplementation. BIOMED RESEARCH INTERNATIONAL 2013; 2013:276808. [PMID: 24175286 PMCID: PMC3794619 DOI: 10.1155/2013/276808] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 08/06/2013] [Accepted: 08/17/2013] [Indexed: 11/22/2022]
Abstract
Friedreich's ataxia (FRDA) is caused by deficient expression of the mitochondrial protein frataxin involved in the formation of iron-sulphur complexes and by consequent oxidative stress. We analysed low-dose tocotrienol supplementation effects on the expression of the three splice variant isoforms (FXN-1, FXN-2, and FXN-3) in mononuclear blood cells of FRDA patients and healthy subjects. In FRDA patients, tocotrienol leads to a specific and significant increase of FXN-3 expression while not affecting FXN-1 and FXN-2 expression. Since no structural and functional details were available for FNX-2 and FXN-3, 3D models were built. FXN-1, the canonical isoform, was then docked on the human iron-sulphur complex, and functional interactions were computed; when FXN-1 was replaced by FXN-2 or FNX-3, we found that the interactions were maintained, thus suggesting a possible biological role for both isoforms in human cells. Finally, in order to evaluate whether tocotrienol enhancement of FXN-3 was mediated by an increase in peroxisome proliferator-activated receptor-γ (PPARG), PPARG expression was evaluated. At a low dose of tocotrienol, the increase of FXN-3 expression appeared to be independent of PPARG expression. Our data show that it is possible to modulate the mRNA expression of the minor frataxin isoforms and that they may have a functional role.
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Affiliation(s)
- Provvidenza Maria Abruzzo
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, 40126 Bologna, Italy
| | - Marina Marini
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, 40126 Bologna, Italy
| | - Alessandra Bolotta
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, 40126 Bologna, Italy
| | - Gemma Malisardi
- Department of Pharmaceutical Sciences, University of Ferrara, 44100 Ferrara, Italy
| | - Stefano Manfredini
- Department of Pharmaceutical Sciences, University of Ferrara, 44100 Ferrara, Italy
| | - Alessandro Ghezzo
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, 40126 Bologna, Italy
- ANFFAS ONLUS Macerata, 62100 Macerata, Italy
| | - Antonella Pini
- Child Neurology and Psychiatry Unit, IRCCS Institute of Neurological Sciences of Bologna, Bologna, 40100 Bologna, Italy
| | - Gianluca Tasco
- Biocomputing Group, CIRI-Health Science and Technology, Department of Biology, Bologna 40126, Italy
| | - Rita Casadio
- Biocomputing Group, CIRI-Health Science and Technology, Department of Biology, Bologna 40126, Italy
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25
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Liu B, Anderson SL, Qiu J, Rubin BY. Cardiac glycosides correct aberrant splicing of IKBKAP-encoded mRNA in familial dysautonomia derived cells by suppressing expression of SRSF3. FEBS J 2013; 280:3632-46. [PMID: 23711097 DOI: 10.1111/febs.12355] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 04/30/2013] [Accepted: 05/21/2013] [Indexed: 12/11/2022]
Abstract
The ability to modulate the production of the wild-type transcript in cells bearing the splice-altering familial dysautonomia (FD) causing mutation in the IKBKAP gene prompted a study of the impact of a panel of pharmaceuticals on the splicing of this transcript, which revealed the ability of the cardiac glycoside digoxin to increase the production of the wild-type, exon-20-containing, IKBKAP-encoded transcript and the full-length IκB-kinase-complex-associated protein in FD-derived cells. Characterization of the cis elements and trans factors involved in the digoxin-mediated effect on splicing reveals that this response is dependent on an SRSF3 binding site(s) located in the intron 5' of the alternatively spliced exon and that digoxin mediates its effect by suppressing the level of the SRSF3 protein. Characterization of the digoxin-mediated effect on the RNA splicing process was facilitated by the identification of several RNA splicing events in which digoxin treatment mediates the enhanced inclusion of exonic sequence. Moreover, we demonstrate the ability of digoxin to impact the splicing process in neuronal cells, a cell type profoundly impacted by FD. This study represents the first demonstration that digoxin possesses splice-altering capabilities that are capable of reversing the impact of the FD-causing mutation. These findings support the clinical evaluation of the impact of digoxin on the FD patient population.
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Affiliation(s)
- Bo Liu
- Laboratory for Familial Dysautonomia Research, Department of Biological Sciences, Fordham University, Bronx, NY 10458, USA
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Braicu C, Ladomery MR, Chedea VS, Irimie A, Berindan-Neagoe I. The relationship between the structure and biological actions of green tea catechins. Food Chem 2013; 141:3282-9. [PMID: 23871088 DOI: 10.1016/j.foodchem.2013.05.122] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 10/07/2012] [Accepted: 05/24/2013] [Indexed: 12/12/2022]
Abstract
Catechins and their gallate esters are a class of polyphenolic compounds. The catechin subclass known as flavan-3-ols have recently attracted much attention with regards to their beneficial effect on human health. Their biological actions are dependent on the structure of the compounds and vary according to cell type. They are best known as powerful antioxidants; however depending on the doses they also exhibit prooxidant effects. The anti- or prooxidant effects of green tea catechins have been implicated in the modulation of several cellular functions often associated with strong chemoprotective properties. This review summarises the benefit catechins to human health, the main molecular pathways modulated by catechins. The relationship between the structure and activity of the catechins needs to be studied further. In the future, the structure of catechins could be modified so as to synthesise novel compounds with more specific beneficial properties and higher bioavailability.
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Affiliation(s)
- Cornelia Braicu
- Department of Functional Genomics and Experimental Pathology, The Oncological Institute Prof. Dr. Ion Chiricuta, Cluj-Napoca, Romania.
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Havens MA, Duelli DM, Hastings ML. Targeting RNA splicing for disease therapy. WILEY INTERDISCIPLINARY REVIEWS. RNA 2013; 4:247-66. [PMID: 23512601 PMCID: PMC3631270 DOI: 10.1002/wrna.1158] [Citation(s) in RCA: 126] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Splicing of pre-messenger RNA into mature messenger RNA is an essential step for the expression of most genes in higher eukaryotes. Defects in this process typically affect cellular function and can have pathological consequences. Many human genetic diseases are caused by mutations that cause splicing defects. Furthermore, a number of diseases are associated with splicing defects that are not attributed to overt mutations. Targeting splicing directly to correct disease-associated aberrant splicing is a logical approach to therapy. Splicing is a favorable intervention point for disease therapeutics, because it is an early step in gene expression and does not alter the genome. Significant advances have been made in the development of approaches to manipulate splicing for therapy. Splicing can be manipulated with a number of tools including antisense oligonucleotides, modified small nuclear RNAs (snRNAs), trans-splicing, and small molecule compounds, all of which have been used to increase specific alternatively spliced isoforms or to correct aberrant gene expression resulting from gene mutations that alter splicing. Here we describe clinically relevant splicing defects in disease states, the current tools used to target and alter splicing, specific mutations and diseases that are being targeted using splice-modulating approaches, and emerging therapeutics.
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Affiliation(s)
- Mallory A. Havens
- Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University of Medicine and Science. North Chicago, IL, 60064, USA. No conflicts of interest
| | - Dominik M. Duelli
- Department of Cellular and Molecular Pharmacology, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, 60064, USA. No conflicts of interest
| | - Michelle L. Hastings
- Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University of Medicine and Science. North Chicago, IL, 60064, USA, Phone: 847-578-8517 Fax: 847-578-3253. No conflicts of interest
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Hagen RM, Chedea VS, Mintoff CP, Bowler E, Morse HR, Ladomery MR. Epigallocatechin-3-gallate promotes apoptosis and expression of the caspase 9a splice variant in PC3 prostate cancer cells. Int J Oncol 2013; 43:194-200. [PMID: 23615977 DOI: 10.3892/ijo.2013.1920] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 01/29/2013] [Indexed: 11/06/2022] Open
Abstract
Growing evidence suggests that the flavonoid epigallocatechin-3-gallate (EGCG), notably abundant in green tea, has health-promoting properties. We examined the effect of EGCG on cell survival and apoptosis in the prostate cancer cell line PC3. Cell survival was reduced and apoptosis increased significantly with a low dose of 1 µM EGCG. The ability of the anticancer drug cisplatin to promote apoptosis was enhanced by EGCG. Furthermore, EGCG, both alone and in combination with cisplatin, promoted the expression of the pro-apoptotic splice isoform of caspase 9.
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Affiliation(s)
- Rachel M Hagen
- Centre for Research in Bioscience, Faculty of Health and Life Sciences, University of the West of England, Coldharbour Lane, Frenchay, Bristol BS16 1QY, UK
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Abstract
Hereditary sensory and autonomic neuropathies (HSN/HSAN) are clinically and genetically heterogeneous disorders of the peripheral nervous system that predominantly affect the sensory and autonomic neurons. Hallmark features comprise not only prominent sensory signs and symptoms and ulcerative mutilations but also variable autonomic and motor disturbances. Autosomal dominant and autosomal recessive inheritance has been reported. Molecular genetics studies have identified disease-causing mutations in 11 genes. Some of the affected proteins have nerve-specific roles but underlying mechanisms have also been shown to involve sphingolipid metabolism, vesicular transport, structural integrity, and transcription regulation. Genetic and functional studies have substantially improved the understanding of the pathogenesis of the HSN/HSAN and will help to find preventive and causative therapies in the future.
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Anderson SL, Liu B, Qiu J, Sturm AJ, Schwartz JA, Peters AJ, Sullivan KA, Rubin BY. Nutraceutical-mediated restoration of wild-type levels of IKBKAP-encoded IKAP protein in familial dysautonomia-derived cells. Mol Nutr Food Res 2012; 56:570-9. [PMID: 22495984 DOI: 10.1002/mnfr.201100670] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SCOPE The reported ability to modulate the production of the wild-type transcript in cells bearing the splice-altering familial dysautonomia (FD)-causing mutation in the IKBKAP gene prompted an evaluation of the impact of commonly consumed nutraceuticals on the splicing of this transcript. METHODS AND RESULTS Screening efforts revealed the ability of the isoflavones, genistein, and daidzein, to impact splicing and increase the production of the wild-type, exon-20-containing, transcript, and the full-length IKBKAP-encoded IΚB kinase complex associated protein(IKAP) in FD-derived cells. Genistein was also found to impact splicing in neuronal cells, a cell type profoundly impacted by FD. The simultaneous exposure of FD-derived cells to genistein and epigallocatechin gallate (EGCG) resulted in the almost exclusive production of the exon-20-containing transcript and the production of wild-type amounts of IKAP protein. CONCLUSION This study represents the first demonstration that the isoflavones, genistein and daidzein, possess splice-altering capabilities and that simultaneous treatment with genistein and EGCG reverses the splice-altering impact of the FD-causing mutation. These findings support the clinical evaluation of the therapeutic impact of the combined administration of these two commonly consumed nutraceuticals on this patient population and suggest a broader evaluation of the impact of these nutraceuticals on the in vivo RNA splicing process.
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Affiliation(s)
- Sylvia L Anderson
- Laboratory for Familial Dysautonomia Research, Department of Biological Sciences, Fordham University, Bronx, NY10458, USA
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31
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Alternative splicing interference by xenobiotics. Toxicology 2012; 296:1-12. [DOI: 10.1016/j.tox.2012.01.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 01/21/2012] [Accepted: 01/23/2012] [Indexed: 12/21/2022]
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Christian KM, Song H, Ming GL. Application of reprogrammed patient cells to investigate the etiology of neurological and psychiatric disorders. ACTA ACUST UNITED AC 2012; 7:179-188. [PMID: 34603405 DOI: 10.1007/s11515-012-1216-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Cellular reprogramming allows for the de novo generation of human neurons and glial cells from patients with neurological and psychiatric disorders. Crucially, this technology preserves the genome of the donor individual and thus provides a unique opportunity for systematic investigation of genetic influences on neuronal pathophysiology. Although direct reprogramming of adult somatic cells to neurons is now possible, the majority of recent studies have used induced pluripotent stem cells (iPSCs) derived from patient fibroblasts to generate neural progenitors that can be differentiated to specific neural cell types. Investigations of monogenic diseases have established proof-of-principle for many aspects of cellular disease modeling, including targeted differentiation of neuronal populations and rescue of phenotypes in patient iPSC lines. Refinement of protocols to allow for efficient generation of iPSC lines from large patient cohorts may reveal common functional pathology and genetic interactions in diseases with a polygenic basis. We review several recent studies that illustrate the utility of iPSC-based cellular models of neurodevelopmental and neurodegenerative disorders to identify novel phenotypes and therapeutic approaches.
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Affiliation(s)
- Kimberly M Christian
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hongjun Song
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,The Solomon Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Guo-Li Ming
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,The Solomon Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Rotthier A, Baets J, Timmerman V, Janssens K. Mechanisms of disease in hereditary sensory and autonomic neuropathies. Nat Rev Neurol 2012; 8:73-85. [PMID: 22270030 DOI: 10.1038/nrneurol.2011.227] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Hereditary sensory and autonomic neuropathies (HSANs) are a clinically and genetically heterogeneous group of disorders of the PNS. Progressive degeneration, predominantly of sensory and autonomic neurons, is the main pathological feature in patients with HSAN, and causes prominent sensory loss and ulcerative mutilations in combination with variable autonomic and motor disturbances. Advances in molecular genetics have enabled identification of disease-causing mutations in 12 genes, and studies on the functional effects of these mutations are underway. Although some of the affected proteins--such as nerve growth factor and its receptor--have obvious nerve-specific roles, others are ubiquitously expressed proteins that are involved in sphingolipid metabolism, vesicular transport, transcription regulation and structural integrity. An important challenge in the future will be to understand the common molecular pathways that result in HSANs. Unraveling the mechanisms that underlie sensory and autonomic neurodegeneration could assist in identifying targets for future therapeutic strategies in patients with HSAN. This Review highlights key advances in the understanding of HSANs, including insights into the molecular mechanisms of disease, derived from genetic studies of patients with these disorders.
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Affiliation(s)
- Annelies Rotthier
- VIB Department of Molecular Genetics, University of Antwerp, Universiteitsplein 1, 2610 Antwerpen, Belgium
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Abstract
The remarkable advances in cellular reprogramming have made it possible to generate a renewable source of human neurons from fibroblasts obtained from skin samples of neonates and adults. As a result, we can now investigate the etiology of neurological diseases at the cellular level using neuronal populations derived from patients, which harbor the same genetic mutations thought to be relevant to the risk for pathology. Therapeutic implications include the ability to establish new humanized disease models for understanding mechanisms, conduct high-throughput screening for novel biogenic compounds to reverse or prevent the disease phenotype, identify and engineer genetic rescue of causal mutations, and develop patient-specific cellular replacement strategies. Although this field offers enormous potential for understanding and treating neurological disease, there are still many issues that must be addressed before we can fully exploit this technology. Here we summarize several recent studies presented at a symposium at the 2011 annual meeting of the Society for Neuroscience, which highlight innovative approaches to cellular reprogramming and how this revolutionary technique is being refined to model neurodevelopmental and neurodegenerative diseases, such as autism spectrum disorders, schizophrenia, familial dysautonomia, and Alzheimer's disease.
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Lee G, Studer L. Modelling familial dysautonomia in human induced pluripotent stem cells. Philos Trans R Soc Lond B Biol Sci 2011; 366:2286-96. [PMID: 21727134 DOI: 10.1098/rstb.2011.0026] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Induced pluripotent stem (iPS) cells have considerable promise as a novel tool for modelling human disease and for drug discovery. While the generation of disease-specific iPS cells has become routine, realizing the potential of iPS cells in disease modelling poses challenges at multiple fronts. Such challenges include selecting a suitable disease target, directing the fate of iPS cells into symptom-relevant cell populations, identifying disease-related phenotypes and showing reversibility of such phenotypes using genetic or pharmacological approaches. Finally, the system needs to be scalable for use in modern drug discovery. Here, we will discuss these points in the context of modelling familial dysautonomia (FD, Riley-Day syndrome, hereditary sensory and autonomic neuropathy III (HSAN-III)), a rare genetic disorder in the peripheral nervous system. We have demonstrated three disease-specific phenotypes in FD-iPS-derived cells that can be partially rescued by treating cells with the plant hormone kinetin. Here, we will discuss how to use FD-iPS cells further in high throughput drug discovery assays, in modelling disease severity and in performing mechanistic studies aimed at understanding disease pathogenesis. FD is a rare disease but represents an important testing ground for exploring the potential of iPS cell technology in modelling and treating human disease.
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Affiliation(s)
- Gabsang Lee
- Centre for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Avenue, New York, NY 10065, USA
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36
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Axelrod FB, Liebes L, Gold-Von Simson G, Mendoza S, Mull J, Leyne M, Norcliffe-Kaufmann L, Kaufmann H, Slaugenhaupt SA. Kinetin improves IKBKAP mRNA splicing in patients with familial dysautonomia. Pediatr Res 2011; 70:480-3. [PMID: 21775922 PMCID: PMC3189334 DOI: 10.1203/pdr.0b013e31822e1825] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Familial dysautonomia (FD) is caused by an intronic splice mutation in the IKBKAP gene that leads to partial skipping of exon 20 and tissue-specific reduction in I-κ-B kinase complex-associated protein/elongation protein 1 (IKAP/ELP-1) expression. Kinetin (6-furfurylaminopurine) has been shown to improve splicing and increase WT IKBKAP mRNA and IKAP protein expression in FD cell lines and carriers. To determine whether oral kinetin treatment could alter mRNA splicing in FD subjects and was tolerable, we administered kinetin to eight FD individuals homozygous for the splice mutation. Subjects received 23.5 mg/Kg/d for 28 d. An increase in WT IKBKAP mRNA expression in leukocytes was noted after 8 d in six of eight individuals; after 28 d, the mean increase compared with baseline was significant (p = 0.002). We have demonstrated that kinetin is tolerable in this medically fragile population. Not only did kinetin produce the desired effect on splicing in FD patients but also that effect seems to improve with time despite lack of dose change. This is the first report of a drug that produces in vivo mRNA splicing changes in individuals with FD and supports future long-term trials to determine whether kinetin will prove therapeutic in FD patients.
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Affiliation(s)
- Felicia B Axelrod
- Department of Pediatrics, New York University School of Medicine, New York, New York 10016, USA.
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Shetty RS, Gallagher CS, Chen YT, Hims MM, Mull J, Leyne M, Pickel J, Kwok D, Slaugenhaupt SA. Specific correction of a splice defect in brain by nutritional supplementation. Hum Mol Genet 2011; 20:4093-101. [PMID: 21821670 DOI: 10.1093/hmg/ddr333] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Recent studies emphasize the importance of mRNA splicing in human genetic disease, as 20-30% of all disease-causing mutations are predicted to result in mRNA splicing defects. The plasticity of the mRNA splicing reaction has made these mutations attractive candidates for the development of therapeutics. Familial dysautonomia (FD) is a severe neurodegenerative disorder, and all patients have an intronic IVS20+6T>C splice site mutation in the IKBKAP gene, which results in tissue-specific skipping of exon 20 and a corresponding reduction in ikappaB kinase complex associated protein (IKAP) levels. We created transgenic mouse lines using a human IKBKAP bacterial artificial chromosome (BAC) into which we inserted the IKBKAP splice mutation (FD BAC) and have shown that the transgenic mice exhibit the same tissue-specific aberrant splicing patterns as seen in FD patients. We have previously demonstrated that the plant cytokinin kinetin can significantly improve the production of wild-type IKBKAP transcripts in FD lymphoblast cell lines by improving exon inclusion. In this study, we tested the ability of kinetin to alter IKBKAP splicing in the transgenic mice carrying the FD BAC and show that it corrects IKBKAP splicing in all major tissues assayed, including the brain. The amount of wild-type IKBKAP mRNA and IKAP protein was significantly higher in the kinetin-treated mice. These exciting results prove that treatment of FD, as well as other mechanistically related splicing disorders, with kinetin holds great promise as a potential therapeutic aimed at increasing normal protein levels, which may, in turn, slow disease progression.
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Affiliation(s)
- Ranjit S Shetty
- Center for Human Genetic Research, Massachusetts General Hospital and Harvard Medical School, 185 Cambridge Street, CPZN-5254, Boston, MA 02114, USA
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Phosphatidylserine increases IKBKAP levels in familial dysautonomia cells. PLoS One 2010; 5:e15884. [PMID: 21209961 PMCID: PMC3012102 DOI: 10.1371/journal.pone.0015884] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2010] [Accepted: 11/26/2010] [Indexed: 11/19/2022] Open
Abstract
Familial Dysautonomia (FD) is an autosomal recessive congenital neuropathy that results from abnormal development and progressive degeneration of the sensory and autonomic nervous system. The mutation observed in almost all FD patients is a point mutation at position 6 of intron 20 of the IKBKAP gene; this gene encodes the IκB kinase complex-associated protein (IKAP). The mutation results in a tissue-specific splicing defect: Exon 20 is skipped, leading to reduced IKAP protein expression. Here we show that phosphatidylserine (PS), an FDA-approved food supplement, increased IKAP mRNA levels in cells derived from FD patients. Long-term treatment with PS led to a significant increase in IKAP protein levels in these cells. A conjugate of PS and an omega-3 fatty acid also increased IKAP mRNA levels. Furthermore, PS treatment released FD cells from cell cycle arrest and up-regulated a significant number of genes involved in cell cycle regulation. Our results suggest that PS has potential for use as a therapeutic agent for FD. Understanding its mechanism of action may reveal the mechanism underlying the FD disease.
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Pros E, Fernández-Rodríguez J, Benito L, Ravella A, Capellá G, Blanco I, Serra E, Lázaro C. Modulation of aberrant NF1 pre-mRNA splicing by kinetin treatment. Eur J Hum Genet 2009; 18:614-7. [PMID: 19935827 DOI: 10.1038/ejhg.2009.212] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Neurofibromatosis type 1 is one of the most common neurocutaneous autosomal dominant disorders. It is caused by mutations in the neurofibromatosis type 1 (NF1) gene and approximately 30-40% of them affect the correct splicing of NF1 pre-mRNA. In this report, we evaluate the effect of five different drugs, previously found to modify splicing in several genetic disorders, on the splicing of mutated NF1 alleles. For this purpose, cell lines derived from patients bearing 19 different NF1-splicing defects were used. Our results showed that kinetin partially corrects the splicing defect in four of the studied mutations (c.910C>T, c.3113G>A, c.6724C>T and c.6791dupA). Our study is a valuable contribution to the field because it identifies new exon-skipping events that can be reversed by kinetin treatment and provides new information about kinetin splicing modulation. However, owing to the nature of mutations in our patients, kinetin treatment could not be used as a therapeutic agent in these cases.
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Affiliation(s)
- Eva Pros
- Programa de Diagnòstic Molecular de Càncer Hereditari, Laboratori de Recerca Translacional, Institut Català d'Oncologia-Institut d'Investigació Biomèdica de Bellvitge, L'Hospitalet de Llobregat, Barcelona, Spain
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40
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Modelling pathogenesis and treatment of familial dysautonomia using patient-specific iPSCs. Nature 2009; 461:402-6. [PMID: 19693009 PMCID: PMC2784695 DOI: 10.1038/nature08320] [Citation(s) in RCA: 631] [Impact Index Per Article: 42.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2009] [Accepted: 07/28/2009] [Indexed: 12/14/2022]
Abstract
The isolation of human induced pluripotent stem cells (iPSCs)1-3 offers a novel strategy for modeling human disease. Recent studies have reported the derivation and differentiation of disease-specific human iPSCs4-7. However, a key challenge in the field is the demonstration of disease-related phenotypes and the ability to model pathogenesis and treatment of disease in iPSCs. Familial dysautonomia (FD) is a rare but fatal peripheral neuropathy caused by a point mutation in IKBKAP8 involved in transcriptional elongation9. The disease is characterized by the depletion of autonomic and sensory neurons. The specificity to the peripheral nervous system and the mechanism of neuron loss in FD are poorly understood due to the lack of an appropriate model system. Here we report the derivation of patient specific FD-iPSCs and the directed differentiation into cells of all three germ layers including peripheral neurons. Gene expression analysis in purified FD-iPSC derived lineages demonstrates tissue specific mis-splicing of IKBKAP in vitro. Patient-specific neural crest precursors express particularly low levels of normal IKBKAP transcript suggesting a mechanism for disease specificity. FD pathogenesis is further characterized by transcriptome analysis and cell based assays revealing marked defects in neurogenic differentiation and migration behavior. Finally, we use FD-iPSCs for validating the potency of candidate drugs in reversing aberrant splicing and ameliorating neuronal differentiation and migration. Our study illustrates the promise of iPSC technology for gaining novel insights into human disease pathogenesis and treatment.
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Gold-von Simson G, Goldberg JD, Rolnitzky LM, Mull J, Leyne M, Voustianiouk A, Slaugenhaupt SA, Axelrod FB. Kinetin in familial dysautonomia carriers: implications for a new therapeutic strategy targeting mRNA splicing. Pediatr Res 2009; 65:341-6. [PMID: 19033881 DOI: 10.1203/pdr.0b013e318194fd52] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Familial dysautonomia (FD) is caused by an intronic splice mutation in the IkappaB kinase-associated protein gene (IKBKAP) that leads to partial skipping of exon 20 and tissue-specific reduction of IkappaB kinase-associated protein/elongator protein 1 (IKAP/ELP-1 protein). Kinetin increases IKBKAP mRNA and protein expression in FD cell lines. To determine whether oral kinetin alters IKBKAP splicing in vivo, we administered kinetin to 29 healthy carriers of the major FD mutation for 8 d. Adverse effects, kinetin, and IKBKAP mRNA levels were monitored. In the highest dosing cohorts (23.5 mg/kg/d), the target plasma kinetin level was achieved in 91% of subjects at 2 h. After 8 d, IKBKAP mRNA expression in leukocytes increased as kinetin levels increased. There is a linear association between log plasma kinetin level and corresponding log change from baseline in IKBKAP mRNA expression that allows estimation of IKBKAP mRNA levels because of kinetin ingestion. Adverse effects were transient and mild. This is the first report of in vivo IKBKAP splicing modification and strongly suggests kinetin's therapeutic potential in FD and perhaps in other splicing disorders. Furthermore, our findings support our hypothesis that treatments, which target a particular splicing mutation, can be successfully developed.
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Bian Y, Masuda A, Matsuura T, Ito M, Okushin K, Engel AG, Ohno K. Tannic acid facilitates expression of the polypyrimidine tract binding protein and alleviates deleterious inclusion of CHRNA1 exon P3A due to an hnRNP H-disrupting mutation in congenital myasthenic syndrome. Hum Mol Genet 2009; 18:1229-37. [PMID: 19147685 PMCID: PMC2655771 DOI: 10.1093/hmg/ddp023] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We recently reported that the intronic splice-site mutation IVS3-8G>A of CHRNA1 that encodes the muscle nicotinic acetylcholine receptor alpha subunit disrupts binding of a splicing repressor, hnRNP H. This, in turn, results in exclusive inclusion of the downstream exon P3A. The P3A(+) transcript encodes a non-functional alpha subunit that comprises 50% of the transcripts in normal human skeletal muscle, but its functional significance remains undetermined. In an effort to search for a potential therapy, we screened off-label effects of 960 bioactive chemical compounds and found that tannic acid ameliorates the aberrant splicing due to IVS3-8G>A but without altering the expression of hnRNP H. Therefore, we searched for another splicing trans-factor. We found that the polypyrimidine tract binding protein (PTB) binds close to the 3' end of CHRNA1 intron 3, that PTB induces skipping of exon P3A and that tannic acid increases the expression of PTB in a dose-dependent manner. Deletion assays of the PTB promoter region revealed that the tannic acid-responsive element is between positions -232 and -74 from the translation initiation site. These observations open the door to the discovery of novel therapies based on PTB overexpression and to detecting possible untoward effects of the overexpression.
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Affiliation(s)
- Yang Bian
- Division of Neurogenetics, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya, Japan
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43
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Abstract
Alternative pre-mRNA splicing is an important element in eukaryotic gene expression, as most of the protein-coding genes use this process to generate multiple protein isoforms from a single gene. An increasing number of human diseases are now recognized to be caused by the selection of 'wrong' alternative exons. Research during the last few years identified a number of low-molecular-mass chemical substances that can change alternative exon usage. Most of these substances act by either blocking histone deacetylases or by interfering with the phosphorylation of splicing factors. How the remaining large number of these substances affect splicing is not yet fully understood. The emergence of these low-molecular-mass substances provides not only probes for studying alternative pre-mRNA splicing, but also opens the door to the possible harnessing of these compounds as drugs to control diseases caused by the selection of 'wrong' splice sites.
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Rubin BY, Anderson SL, Kapás L. Can the therapeutic efficacy of tocotrienols in neurodegenerative familial dysautonomia patients be measured clinically? Antioxid Redox Signal 2008; 10:837-41. [PMID: 18177231 DOI: 10.1089/ars.2007.1874] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Familial dysautonomia (FD) is an inherited, fatal, neurodegenerative disorder manifested by autonomic/hypertensive crises and cardiac instability. Patients produce little IKAP, the gene product of the affected mutated gene, and have low levels of monoamine oxidase A (MAO A), whose reduced presence appears to result in an increased accumulation of biogenic amines, which is a trigger for hypertensive crises. As ingestion of tocotrienols elevates IKAP and MAO A in FD patients, we examined their impact on the frequency of hypertensive crises and cardiac function. After 3 to 4 months of tocotrienol ingestion, approximately 80% of patients reported a significant (> or = 50%) decrease in the number of crises. In a smaller group of patients, a postexercise increase in heart rate and a decrease in the QT interval were observed in the majority of participants. Based on these findings, we hypothesize that tocotrienol therapy will improve the long-term clinical outlook and survival of individuals with FD.
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Affiliation(s)
- Berish Y Rubin
- Laboratory for Familial Dysautonomia Research, Fordham University, Bronx, NY 10458, USA.
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Gardiner J, Barton D, Vanslambrouck JM, Braet F, Hall D, Marc J, Overall R. Defects in tongue papillae and taste sensation indicate a problem with neurotrophic support in various neurological diseases. Neuroscientist 2008; 14:240-50. [PMID: 18270312 DOI: 10.1177/1073858407312382] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Neurotrophic support of developing neurons by neurotrophins is of critical importance in the development of fungiform papillae and taste buds. A number of neurological disorders show a decrease or increase in fungiform papillae or taste sensation. These can be grouped into disorders with reduced papillae (Machado-Joseph disease, Stüve-Wiedemann syndrome, familial dysautonomia, dystonia musculorum, and Behçet's disease) and those with taste defects only (Alzheimer's disease, Huntington's disease, hereditary sensory and autonomic neuropathy type IV, and diabetes mellitus). In addition, Parkinson's disease results in increased taste sensation. Here, we hypothesize that the main problem in these disorders is either not enough or too much neurotrophic support. Proneurotrophic drugs such as some antidepressants and aldose reductase inhibitors may prove useful in the treatment of these sensory and central nervous system disorders. Similarly, antineurotrophic drugs may also be useful in Parkinson's disease. Here we show that the protein involved in familial dysautonomia, IKAP, localizes to keratin filaments in HeLa cells, suggesting a role for the keratin cytoskeleton in neurotrophic support.
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Affiliation(s)
- John Gardiner
- School of Biological Sciences, University of Sydney, Australia.
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Gold-von Simson G, Leyne M, Mull J, Rolnitzky LM, Goldberg JD, Berlin D, Axelrod FB, Slaugenhaupt SA. IKBKAP mRNA in peripheral blood leukocytes: a molecular marker of gene expression and splicing in familial dysautonomia. Pediatr Res 2008; 63:186-90. [PMID: 18091349 DOI: 10.1203/pdr.0b013e31815ef74b] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The common familial dysautonomia (FD) mutation results in tissue specific mis-splicing with reduced amount of wild-type (WT) IkappaB kinase associated protein gene (IKBKAP) mRNA and ELP1. ELP1 is a subunit of Elongator, formerly called the IkappaB kinase associated protein (IKAP) protein. We measured IKBKAP mRNA in peripheral blood leukocytes to determine whether FD subjects and carriers have characteristic levels. Estimated mean IKBKAP mRNA levels, measured by quantitative PCR and expressed as amount relative to the noncarrier average, were significantly different for the two groups when not adjusted for age and sex (p < 0.001): FD subjects 0.23, 95% confidence interval (CI) (0.19, 0.28); carriers 0.58, 95% CI (0.50, 0.68); or adjusted for age and sex (p < 0.001): FD subjects 0.21, 95% CI (0.16, 0.26); carriers 0.66, 95% CI (0.55, 0.79). Comparison of IKBKAP mRNA levels of the 22 FD subjects and their related carriers showed a strong correlation, providing evidence for genetic control of splicing efficiency. IKBKAP mRNA levels were not higher in those subjects using tocotrienols or epigallocatechin gallate. Levels of IKBKAP mRNA in peripheral blood leukocytes can be used to assess molecular response to therapies aimed at enhancing exon 20 inclusion and increasing cellular levels of ELP1/IKAP.
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Rubin BY, Anderson SL. The molecular basis of familial dysautonomia: overview, new discoveries and implications for directed therapies. Neuromolecular Med 2007; 10:148-56. [PMID: 17985250 DOI: 10.1007/s12017-007-8019-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Accepted: 10/17/2007] [Indexed: 01/05/2023]
Abstract
Familial dysautonomia (FD) is a sensory and autonomic neuropathy that affects the development and survival of sensory, sympathetic, and some parasympathetic neurons. It is autosomally inherited and occurs almost exclusively among individuals of Ashkenazi Jewish descent. The pathological and clinical manifestations of FD have been extensively studied and therapeutic modalities have, until recently, focused primarily on addressing the symptoms experienced by those with this fatal disorder. The primary FD-causing mutation is an intronic nucleotide substitution that alters the splicing of the IKBKAP-derived transcript. Recent efforts have resulted in the development of new therapeutic modalities that facilitate the increased production of the correctly spliced transcript and mitigate the symptoms of those with FD. Furthermore, the recent demonstration of the reduced presence of monoamine oxidase A in cells and tissues of individuals with FD has provided new insight into the cause of hypertensive crises experienced by these patients.
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Affiliation(s)
- Berish Y Rubin
- Department of Biological Sciences, Laboratory for Familial Dysautonomia Research, Fordham University, 441 East Fordham Road, Bronx, NY 10458, USA.
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Sakla MS, Lorson CL. Induction of full-length survival motor neuron by polyphenol botanical compounds. Hum Genet 2007; 122:635-43. [PMID: 17962980 DOI: 10.1007/s00439-007-0441-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2007] [Accepted: 10/16/2007] [Indexed: 11/29/2022]
Abstract
The loss of survival motor neuron-1 (SMN1) is responsible for the development of the neurodegenerative disorder spinal muscular atrophy (SMA). A nearly identical copy of SMN1 is present on the same chromosomal region called SMN2. While SMN2 encodes a normal SMN protein, the majority of SMN2-derived transcripts are alternatively spliced, resulting in a truncated protein that lacks the 16 amino acids encoded by SMN exon 7. Numerous studies have shown that the SMN2-derived protein product, called SMNDelta7, is unstable and dysfunctional. Therefore, identifying molecules that stimulate full-length SMN expression from the SMN2 gene could lead to the development of effective therapies for a broad range of SMA patient populations. Polyphenol compounds have been shown to provide benefit in varied genetic disease contexts. For example, epigallocatechin galate (EGCG) was found to correct aberrant alternative mRNA splicing in familiar dysautonomia (FD). A series of polyphenols were screened and a subset was shown to increase full-length SMN expression from SMN2. Curcumin, EGCG, and resveratrol increased exon 7 inclusion of SMN2 transcripts in transient reporter assays. In SMA patient fibroblasts, these compounds stimulated the production of full-length SMN RNA and protein as well as the formation of SMN-containing nuclear gems. Collectively, these compounds elevated total SMN concentrations in SMA patient fibroblasts, potentially through the modulation of SMN2 exon 7 alternative splicing.
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Affiliation(s)
- Mary S Sakla
- Department of Veterinary Pathobiology, Life Sciences Center, University of Missouri, Room 471G, Columbia, MO, 65211-7310, USA
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Hims MM, Shetty RS, Pickel J, Mull J, Leyne M, Liu L, Gusella JF, Slaugenhaupt SA. A humanized IKBKAP transgenic mouse models a tissue-specific human splicing defect. Genomics 2007; 90:389-96. [PMID: 17644305 PMCID: PMC1976430 DOI: 10.1016/j.ygeno.2007.05.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Revised: 05/27/2007] [Accepted: 05/30/2007] [Indexed: 12/18/2022]
Abstract
Familial dysautonomia (FD) is a severe hereditary sensory and autonomic neuropathy, and all patients with FD have a splice mutation in the IKBKAP gene. The FD splice mutation results in variable, tissue-specific skipping of exon 20 in IKBKAP mRNA, which leads to reduced IKAP protein levels. The development of therapies for FD will require suitable mouse models for preclinical studies. In this study, we report the generation and characterization of a mouse model carrying the complete human IKBKAP locus with the FD IVS20+6T-->C splice mutation. We show that the mutant IKBKAP transgene is misspliced in this model in a tissue-specific manner that replicates the pattern seen in FD patient tissues. Creation of this humanized mouse is the first step toward development of a complex phenotypic model of FD. These transgenic mice are an ideal model system for testing the effectiveness of therapeutic agents that target the missplicing defect. Last, these mice will permit direct studies of tissue-specific splicing and the identification of regulatory factors that play a role in complex gene expression.
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Affiliation(s)
- Matthew M. Hims
- Center for Human Genetic Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Ranjit S. Shetty
- Center for Human Genetic Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - James Pickel
- National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA
| | - James Mull
- Center for Human Genetic Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Maire Leyne
- Center for Human Genetic Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Lijuan Liu
- Center for Human Genetic Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - James F. Gusella
- Center for Human Genetic Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Susan A. Slaugenhaupt
- Center for Human Genetic Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- *corresponding author: Susan A Slaugenhaupt, MGH Center for Human Genetic Research, 185 Cambridge Street, CPZN-5254, Boston , MA 02114, Tel: 617-643-3091; Fax: 617-726-5735;
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Abstract
The world of the child with familial dysautonomia (FD), a genetic disorder affecting development of the sensory and autonomic nervous system, is not idyllic. However, over the last 35 years advances in supportive treatments have improved morbidity and mortality. Recent genetic breakthroughs have further expanded thinking about this disorder and suggested innovative approaches to modifying genetic expression. This article reviews the current supportive treatment modalities and their rationale, as well as the suggested new treatments that may alter the function and prognosis of an individual affected with FD.
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Affiliation(s)
- Felicia B Axelrod
- Dysautonomia Treatment and Evaluation Center, NYU Medical Center, 530 First Avenue, suite 9Q, New York, NY 10016, USA.
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