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Martella N, Pensabene D, Varone M, Colardo M, Petraroia M, Sergio W, La Rosa P, Moreno S, Segatto M. Bromodomain and Extra-Terminal Proteins in Brain Physiology and Pathology: BET-ing on Epigenetic Regulation. Biomedicines 2023; 11:biomedicines11030750. [PMID: 36979729 PMCID: PMC10045827 DOI: 10.3390/biomedicines11030750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 02/24/2023] [Accepted: 02/25/2023] [Indexed: 03/06/2023] Open
Abstract
BET proteins function as histone code readers of acetylated lysins that determine the positive regulation in transcription of genes involved in cell cycle progression, differentiation, inflammation, and many other pathways. In recent years, thanks to the development of BET inhibitors, interest in this protein family has risen for its relevance in brain development and function. For example, experimental evidence has shown that BET modulation affects neuronal activity and the expression of genes involved in learning and memory. In addition, BET inhibition strongly suppresses molecular pathways related to neuroinflammation. These observations suggest that BET modulation may play a critical role in the onset and during the development of diverse neurodegenerative and neuropsychiatric disorders, such as Alzheimer’s disease, fragile X syndrome, and Rett syndrome. In this review article, we summarize the most recent evidence regarding the involvement of BET proteins in brain physiology and pathology, as well as their pharmacological potential as targets for therapeutic purposes.
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Affiliation(s)
- Noemi Martella
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Daniele Pensabene
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
- Department of Science, University Roma Tre, Viale Marconi 446, 00146 Rome, Italy
- Laboratory of Neurodevelopment, Neurogenetics and Neuromolecular Biology, IRCCS Santa Lucia Foundation, 64 via del Fosso di Fiorano, 00179 Rome, Italy
| | - Michela Varone
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Mayra Colardo
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Michele Petraroia
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - William Sergio
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Piergiorgio La Rosa
- Division of Neuroscience, Department of Psychology, Sapienza University of Rome, via dei Marsi 78, 00185 Rome, Italy
| | - Sandra Moreno
- Department of Science, University Roma Tre, Viale Marconi 446, 00146 Rome, Italy
- Laboratory of Neurodevelopment, Neurogenetics and Neuromolecular Biology, IRCCS Santa Lucia Foundation, 64 via del Fosso di Fiorano, 00179 Rome, Italy
| | - Marco Segatto
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
- Correspondence:
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Jiang D, Li T, Guo C, Tang TS, Liu H. Small molecule modulators of chromatin remodeling: from neurodevelopment to neurodegeneration. Cell Biosci 2023; 13:10. [PMID: 36647159 PMCID: PMC9841685 DOI: 10.1186/s13578-023-00953-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 01/03/2023] [Indexed: 01/18/2023] Open
Abstract
The dynamic changes in chromatin conformation alter the organization and structure of the genome and further regulate gene transcription. Basically, the chromatin structure is controlled by reversible, enzyme-catalyzed covalent modifications to chromatin components and by noncovalent ATP-dependent modifications via chromatin remodeling complexes, including switch/sucrose nonfermentable (SWI/SNF), inositol-requiring 80 (INO80), imitation switch (ISWI) and chromodomain-helicase DNA-binding protein (CHD) complexes. Recent studies have shown that chromatin remodeling is essential in different stages of postnatal and adult neurogenesis. Chromatin deregulation, which leads to defects in epigenetic gene regulation and further pathological gene expression programs, often causes a wide range of pathologies. This review first gives an overview of the regulatory mechanisms of chromatin remodeling. We then focus mainly on discussing the physiological functions of chromatin remodeling, particularly histone and DNA modifications and the four classes of ATP-dependent chromatin-remodeling enzymes, in the central and peripheral nervous systems under healthy and pathological conditions, that is, in neurodegenerative disorders. Finally, we provide an update on the development of potent and selective small molecule modulators targeting various chromatin-modifying proteins commonly associated with neurodegenerative diseases and their potential clinical applications.
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Affiliation(s)
- Dongfang Jiang
- grid.458458.00000 0004 1792 6416State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101 China ,grid.410726.60000 0004 1797 8419Chinese Academy of Sciences, University of Chinese Academy of Sciences, Beijing, 100101 China
| | - Tingting Li
- grid.458458.00000 0004 1792 6416State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101 China ,grid.410726.60000 0004 1797 8419Chinese Academy of Sciences, University of Chinese Academy of Sciences, Beijing, 100101 China
| | - Caixia Guo
- grid.9227.e0000000119573309Beijing Institute of Genomics, Chinese Academy of Sciences/China National Center for Bioinformation, Beijing, 100101 China ,grid.410726.60000 0004 1797 8419Chinese Academy of Sciences, University of Chinese Academy of Sciences, Beijing, 100101 China
| | - Tie-Shan Tang
- grid.458458.00000 0004 1792 6416State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101 China ,grid.512959.3Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, 100101 China ,grid.410726.60000 0004 1797 8419Chinese Academy of Sciences, University of Chinese Academy of Sciences, Beijing, 100101 China
| | - Hongmei Liu
- grid.458458.00000 0004 1792 6416State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101 China ,grid.512959.3Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, 100101 China
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Meijboom KE, Abdallah A, Fordham NP, Nagase H, Rodriguez T, Kraus C, Gendron TF, Krishnan G, Esanov R, Andrade NS, Rybin MJ, Ramic M, Stephens ZD, Edraki A, Blackwood MT, Kahriman A, Henninger N, Kocher JPA, Benatar M, Brodsky MH, Petrucelli L, Gao FB, Sontheimer EJ, Brown RH, Zeier Z, Mueller C. CRISPR/Cas9-mediated excision of ALS/FTD-causing hexanucleotide repeat expansion in C9ORF72 rescues major disease mechanisms in vivo and in vitro. Nat Commun 2022; 13:6286. [PMID: 36271076 PMCID: PMC9587249 DOI: 10.1038/s41467-022-33332-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 09/13/2022] [Indexed: 12/25/2022] Open
Abstract
A GGGGCC24+ hexanucleotide repeat expansion (HRE) in the C9ORF72 gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), fatal neurodegenerative diseases with no cure or approved treatments that substantially slow disease progression or extend survival. Mechanistic underpinnings of neuronal death include C9ORF72 haploinsufficiency, sequestration of RNA-binding proteins in the nucleus, and production of dipeptide repeat proteins. Here, we used an adeno-associated viral vector system to deliver CRISPR/Cas9 gene-editing machineries to effectuate the removal of the HRE from the C9ORF72 genomic locus. We demonstrate successful excision of the HRE in primary cortical neurons and brains of three mouse models containing the expansion (500-600 repeats) as well as in patient-derived iPSC motor neurons and brain organoids (450 repeats). This resulted in a reduction of RNA foci, poly-dipeptides and haploinsufficiency, major hallmarks of C9-ALS/FTD, making this a promising therapeutic approach to these diseases.
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Affiliation(s)
- Katharina E. Meijboom
- grid.168645.80000 0001 0742 0364Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01605 USA ,grid.168645.80000 0001 0742 0364Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Abbas Abdallah
- grid.168645.80000 0001 0742 0364Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Nicholas P. Fordham
- grid.168645.80000 0001 0742 0364Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Hiroko Nagase
- grid.168645.80000 0001 0742 0364Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Tomás Rodriguez
- grid.168645.80000 0001 0742 0364RNA Therapeutics Institute and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Carolyn Kraus
- grid.168645.80000 0001 0742 0364RNA Therapeutics Institute and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Tania F. Gendron
- grid.417467.70000 0004 0443 9942Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Gopinath Krishnan
- grid.168645.80000 0001 0742 0364Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Rustam Esanov
- grid.26790.3a0000 0004 1936 8606Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL 33136 USA
| | - Nadja S. Andrade
- grid.26790.3a0000 0004 1936 8606Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL 33136 USA
| | - Matthew J. Rybin
- grid.26790.3a0000 0004 1936 8606Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL 33136 USA
| | - Melina Ramic
- grid.26790.3a0000 0004 1936 8606Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL 33136 USA
| | - Zachary D. Stephens
- grid.66875.3a0000 0004 0459 167XDepartment of Quantitative Health Sciences. Mayo Clinic, Rochester, MN 55905 USA
| | - Alireza Edraki
- grid.168645.80000 0001 0742 0364RNA Therapeutics Institute and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Meghan T. Blackwood
- grid.168645.80000 0001 0742 0364Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Aydan Kahriman
- grid.168645.80000 0001 0742 0364Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Nils Henninger
- grid.168645.80000 0001 0742 0364Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Jean-Pierre A. Kocher
- grid.66875.3a0000 0004 0459 167XDepartment of Quantitative Health Sciences. Mayo Clinic, Rochester, MN 55905 USA
| | - Michael Benatar
- grid.26790.3a0000 0004 1936 8606Department of Neurology, University of Miami Miller School of Medicine, Miami, FL 33136 USA
| | - Michael H. Brodsky
- grid.168645.80000 0001 0742 0364Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Leonard Petrucelli
- grid.417467.70000 0004 0443 9942Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Fen-Biao Gao
- grid.168645.80000 0001 0742 0364Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Erik J. Sontheimer
- grid.168645.80000 0001 0742 0364RNA Therapeutics Institute and Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Robert H. Brown
- grid.168645.80000 0001 0742 0364Department of Neurology, University of Massachusetts Medical School, Worcester, MA 01605 USA
| | - Zane Zeier
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL, 33136, USA.
| | - Christian Mueller
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, 01605, USA.
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van Zundert B, Montecino M. Epigenetic Changes and Chromatin Reorganization in Brain Function: Lessons from Fear Memory Ensemble and Alzheimer’s Disease. Int J Mol Sci 2022; 23:ijms232012081. [PMID: 36292933 PMCID: PMC9602769 DOI: 10.3390/ijms232012081] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/03/2022] [Accepted: 10/05/2022] [Indexed: 11/16/2022] Open
Abstract
Healthy brain functioning in mammals requires a continuous fine-tuning of gene expression. Accumulating evidence over the last three decades demonstrates that epigenetic mechanisms and dynamic changes in chromatin organization are critical components during the control of gene transcription in neural cells. Recent genome-wide analyses show that the regulation of brain genes requires the contribution of both promoter and long-distance enhancer elements, which must functionally interact with upregulated gene expression in response to physiological cues. Hence, a deep comprehension of the mechanisms mediating these enhancer–promoter interactions (EPIs) is critical if we are to understand the processes associated with learning, memory and recall. Moreover, the onset and progression of several neurodegenerative diseases and neurological alterations are found to be strongly associated with changes in the components that support and/or modulate the dynamics of these EPIs. Here, we overview relevant discoveries in the field supporting the role of the chromatin organization and of specific epigenetic mechanisms during the control of gene transcription in neural cells from healthy mice subjected to the fear conditioning paradigm, a relevant model to study memory ensemble. Additionally, special consideration is dedicated to revising recent results generated by investigators working with animal models and human postmortem brain tissue to address how changes in the epigenome and chromatin architecture contribute to transcriptional dysregulation in Alzheimer’s disease, a widely studied neurodegenerative disease. We also discuss recent developments of potential new therapeutic strategies involving epigenetic editing and small chromatin-modifying molecules (or epidrugs).
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Affiliation(s)
- Brigitte van Zundert
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago 8370186, Chile
- CARE Biomedical Research Center, Santiago 8330005, Chile
- Correspondence: (B.v.Z.); (M.M.)
| | - Martin Montecino
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Santiago 8370186, Chile
- Millennium Institute Center for Genome Regulation CRG, Santiago 8370186, Chile
- Correspondence: (B.v.Z.); (M.M.)
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Ramic M, Andrade NS, Rybin MJ, Esanov R, Wahlestedt C, Benatar M, Zeier Z. Epigenetic Small Molecules Rescue Nucleocytoplasmic Transport and DNA Damage Phenotypes in C9ORF72 ALS/FTD. Brain Sci 2021; 11:brainsci11111543. [PMID: 34827542 PMCID: PMC8616043 DOI: 10.3390/brainsci11111543] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/11/2021] [Accepted: 11/18/2021] [Indexed: 01/04/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neurodegenerative disease with available treatments only marginally slowing progression or improving survival. A hexanucleotide repeat expansion mutation in the C9ORF72 gene is the most commonly known genetic cause of both sporadic and familial cases of ALS and frontotemporal dementia (FTD). The C9ORF72 expansion mutation produces five dipeptide repeat proteins (DPRs), and while the mechanistic determinants of DPR-mediated neurotoxicity remain incompletely understood, evidence suggests that disruption of nucleocytoplasmic transport and increased DNA damage contributes to pathology. Therefore, characterizing these disturbances and determining the relative contribution of different DPRs is needed to facilitate the development of novel therapeutics for C9ALS/FTD. To this end, we generated a series of nucleocytoplasmic transport “biosensors”, composed of the green fluorescent protein (GFP), fused to different classes of nuclear localization signals (NLSs) and nuclear export signals (NESs). Using these biosensors in conjunction with automated microscopy, we investigated the role of the three most neurotoxic DPRs (PR, GR, and GA) on seven nuclear import and two export pathways. In addition to other DPRs, we found that PR had pronounced inhibitory effects on the classical nuclear export pathway and several nuclear import pathways. To identify compounds capable of counteracting the effects of PR on nucleocytoplasmic transport, we developed a nucleocytoplasmic transport assay and screened several commercially available compound libraries, totaling 2714 compounds. In addition to restoring nucleocytoplasmic transport efficiencies, hits from the screen also counteract the cytotoxic effects of PR. Selected hits were subsequently tested for their ability to rescue another C9ALS/FTD phenotype—persistent DNA double strand breakage. Overall, we found that DPRs disrupt multiple nucleocytoplasmic transport pathways and we identified small molecules that counteract these effects—resulting in increased viability of PR-expressing cells and decreased DNA damage markers in patient-derived motor neurons. Several HDAC inhibitors were validated as hits, supporting previous studies that show that HDAC inhibitors confer therapeutic effects in neurodegenerative models.
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Affiliation(s)
- Melina Ramic
- Center for Therapeutic Innovation, Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Miami, FL 33136, USA; (M.R.); (N.S.A.); (M.J.R.); (R.E.); (C.W.)
| | - Nadja S. Andrade
- Center for Therapeutic Innovation, Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Miami, FL 33136, USA; (M.R.); (N.S.A.); (M.J.R.); (R.E.); (C.W.)
| | - Matthew J. Rybin
- Center for Therapeutic Innovation, Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Miami, FL 33136, USA; (M.R.); (N.S.A.); (M.J.R.); (R.E.); (C.W.)
| | - Rustam Esanov
- Center for Therapeutic Innovation, Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Miami, FL 33136, USA; (M.R.); (N.S.A.); (M.J.R.); (R.E.); (C.W.)
| | - Claes Wahlestedt
- Center for Therapeutic Innovation, Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Miami, FL 33136, USA; (M.R.); (N.S.A.); (M.J.R.); (R.E.); (C.W.)
| | - Michael Benatar
- Department of Neurology, University of Miami Miller School of Medicine, 1120 NW 14th St., Miami, FL 33136, USA;
| | - Zane Zeier
- Center for Therapeutic Innovation, Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Miami, FL 33136, USA; (M.R.); (N.S.A.); (M.J.R.); (R.E.); (C.W.)
- Correspondence: ; Tel.: +1-305-243-1367
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Handal T, Eiges R. Correction of Heritable Epigenetic Defects Using Editing Tools. Int J Mol Sci 2021; 22:ijms22083966. [PMID: 33921346 PMCID: PMC8070094 DOI: 10.3390/ijms22083966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/02/2021] [Accepted: 04/07/2021] [Indexed: 11/21/2022] Open
Abstract
Epimutations refer to mistakes in the setting or maintenance of epigenetic marks in the chromatin. They lead to mis-expression of genes and are often secondary to germline transmitted mutations. As such, they are the cause for a considerable number of genetically inherited conditions in humans. The correction of these types of epigenetic defects constitutes a good paradigm to probe the fundamental mechanisms underlying the development of these diseases, and the molecular basis for the establishment, maintenance and regulation of epigenetic modifications in general. Here, we review the data to date, which is limited to repetitive elements, that relates to the applications of key editing tools for addressing the epigenetic aspects of various epigenetically regulated diseases. For each approach we summarize the efforts conducted to date, highlight their contribution to a better understanding of the molecular basis of epigenetic mechanisms, describe the limitations of each approach and suggest perspectives for further exploration in this field.
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Affiliation(s)
- Tayma Handal
- Stem Cell Research Laboratory, Medical Genetics Institute Shaare Zedek Medical Center, Jerusalem 91031, Israel;
- School of Medicine, The Hebrew University, Campus Ein Kerem, Jerusalem 91120, Israel
| | - Rachel Eiges
- Stem Cell Research Laboratory, Medical Genetics Institute Shaare Zedek Medical Center, Jerusalem 91031, Israel;
- School of Medicine, The Hebrew University, Campus Ein Kerem, Jerusalem 91120, Israel
- Correspondence:
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Quezada E, Cappelli C, Diaz I, Jury N, Wightman N, Brown RH, Montecino M, van Zundert B. BET bromodomain inhibitors PFI-1 and JQ1 are identified in an epigenetic compound screen to enhance C9ORF72 gene expression and shown to ameliorate C9ORF72-associated pathological and behavioral abnormalities in a C9ALS/FTD model. Clin Epigenetics 2021; 13:56. [PMID: 33726839 PMCID: PMC7962347 DOI: 10.1186/s13148-021-01039-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 02/23/2021] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND An intronic GGGGCC (G4C2) hexanucleotide repeat expansion (HRE) in the C9ORF72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), referred to as C9ALS/FTD. No cure or effective treatment exist for C9ALS/FTD. Three major molecular mechanisms have emerged to explain C9ALS/FTD disease mechanisms: (1) C9ORF72 loss-of-function through haploinsufficiency, (2) dipeptide repeat (DPR) proteins mediated toxicity by the translation of the repeat RNAs, and more controversial, (3) RNA-mediated toxicity by bidirectional transcription of the repeats that form intranuclear RNA foci. Recent studies indicate a double-hit pathogenic mechanism in C9ALS/FTD, where reduced C9ORF72 protein levels lead to impaired clearance of toxic DPRs. Here we explored whether pharmacological compounds can revert these pathological hallmarks in vitro and cognitive impairment in a C9ALS/FTD mouse model (C9BAC). We specifically focused our study on small molecule inhibitors targeting chromatin-regulating proteins (epidrugs) with the goal of increasing C9ORF72 gene expression and reduce toxic DPRs. RESULTS We generated luciferase reporter cell lines containing 10 (control) or ≥ 90 (mutant) G4C2 HRE located between exon 1a and 1b of the human C9ORF72 gene. In a screen of 14 different epidrugs targeting bromodomains, chromodomains and histone-modifying enzymes, we found that several bromodomain and extra-terminal domain (BET) inhibitors (BETi), including PFI-1 and JQ1, increased luciferase reporter activity. Using primary cortical cultures from C9BAC mice, we further found that PFI-1 treatment increased the expression of V1-V3 transcripts of the human mutant C9ORF72 gene, reduced poly(GP)-DPR inclusions but enhanced intranuclear RNA foci. We also tested whether JQ1, an BETi previously shown to reach the mouse brain by intraperitoneal (i.p.) injection, can revert behavioral abnormalities in C9BAC mice. Interestingly, it was found that JQ1 administration (daily i.p. administration for 7 days) rescued hippocampal-dependent cognitive deficits in C9BAC mice. CONCLUSIONS Our findings place BET bromodomain inhibitors as a potential therapy for C9ALS/FTD by ameliorating C9ORF72-associated pathological and behavioral abnormalities. Our finding that PFI-1 increases accumulation of intranuclear RNA foci is in agreement with recent data in flies suggesting that nuclear RNA foci can be neuroprotective by sequestering repeat transcripts that result in toxic DPRs.
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Affiliation(s)
- Esteban Quezada
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Claudio Cappelli
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Iván Diaz
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Nur Jury
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile
| | - Nicholas Wightman
- Department of Neurology, University of Massachusetts Medical School (UMMS), Worcester, MA, USA
| | - Robert H Brown
- Department of Neurology, University of Massachusetts Medical School (UMMS), Worcester, MA, USA
| | - Martín Montecino
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.
- FONDAP Center for Genome Regulation, Santiago, Chile.
| | - Brigitte van Zundert
- Institute of Biomedical Sciences (ICB), Faculty of Medicine & Faculty of Life Sciences, Universidad Andres Bello, Santiago, Chile.
- Department of Neurology, University of Massachusetts Medical School (UMMS), Worcester, MA, USA.
- CARE Biomedical Research Center, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.
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Kuznetsoff JN, Owens DA, Lopez A, Rodriguez DA, Chee NT, Kurtenbach S, Bilbao D, Roberts ER, Volmar CH, Wahlestedt C, Brothers SP, Harbour JW. Dual Screen for Efficacy and Toxicity Identifies HDAC Inhibitor with Distinctive Activity Spectrum for BAP1-Mutant Uveal Melanoma. Mol Cancer Res 2020; 19:215-222. [PMID: 33077485 DOI: 10.1158/1541-7786.mcr-20-0434] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 08/27/2020] [Accepted: 10/13/2020] [Indexed: 11/16/2022]
Abstract
Drug screens leading to successful targeted therapies in cancer have been mainly based on cell viability assays identifying inhibitors of dominantly acting oncogenes. In contrast, there has been little success in discovering targeted therapies that reverse the effects of inactivating mutations in tumor-suppressor genes. BAP1 is one such tumor suppressor that is frequently inactivated in a variety of cancers, including uveal melanoma, renal cell carcinoma, and mesothelioma. Because BAP1 is an epigenetic transcriptional regulator of developmental genes, we designed a two-phase drug screen involving a cell-based rescue screen of transcriptional repression caused by BAP1 loss, followed by an in vivo screen of lead compounds for rescue of a BAP1-deficient phenotype with minimal toxicity in Xenopus embryos. The first screen identified 9 compounds, 8 of which were HDAC inhibitors. The second screen eliminated all except one compound due to inefficacy or toxicity. The resulting lead compound, quisinostat, has a distinctive activity spectrum, including high potency against HDAC4, which was recently shown to be a key target of BAP1. Quisinostat was further validated in a mouse model and found to prevent the growth of BAP1-mutant uveal melanomas. This innovative strategy demonstrates the potential for identifying therapeutic compounds that target tumor-suppressor mutations in cancer. IMPLICATIONS: Few drugs have been identified that target mutations in tumor suppressors. Using a novel 2-step screening approach, strategy, we identified quisinostat as a candidate for therapy in BAP1-mutant uveal melanoma. HDAC4 is implicated as a key target in uveal melanoma and perhaps other BAP1-mutant cancers.
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Affiliation(s)
- Jeffim N Kuznetsoff
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Dawn A Owens
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Andy Lopez
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Daniel A Rodriguez
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Nancy T Chee
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, Florida
| | - Stefan Kurtenbach
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Daniel Bilbao
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
| | - Evan R Roberts
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
| | - Claude-Henry Volmar
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, Florida
| | - Claes Wahlestedt
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, Florida
| | - Shaun P Brothers
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine, Miami, Florida
| | - J William Harbour
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida.
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, Florida
- Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, Miami, Florida
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9
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BET bromodomains as novel epigenetic targets for brain health and disease. Neuropharmacology 2020; 181:108306. [PMID: 32946883 DOI: 10.1016/j.neuropharm.2020.108306] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 09/09/2020] [Accepted: 09/11/2020] [Indexed: 12/15/2022]
Abstract
Epigenetic pharmacotherapy for CNS-related diseases is a burgeoning area of research. In particular, members of the bromodomain and extra-terminal domain (BET) family of proteins have emerged as intriguing therapeutic targets due to their putative involvement in an array of brain diseases. With their ability to bind to acetylated histones and act as a scaffold for chromatin modifying complexes, BET proteins were originally thought of as passive epigenetic 'reader' proteins. However, new research depicts a more complex reality where BET proteins act as key nodes in lineage-specific and signal-dependent transcriptional mechanisms to influence disease-relevant functions. Amid a recent wave of drug development efforts from basic scientists and pharmaceutical companies, BET inhibitors are currently being studied in several CNS-related disease models, but safety and tolerability remain a concern. Here we review the progress in understanding the neurobiological mechanisms of BET proteins and the therapeutic potential of targeting BET proteins for brain health and disease.
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10
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Andrade NS, Ramic M, Esanov R, Liu W, Rybin MJ, Gaidosh G, Abdallah A, Del’Olio S, Huff TC, Chee NT, Anatha S, Gendron TF, Wahlestedt C, Zhang Y, Benatar M, Mueller C, Zeier Z. Dipeptide repeat proteins inhibit homology-directed DNA double strand break repair in C9ORF72 ALS/FTD. Mol Neurodegener 2020; 15:13. [PMID: 32093728 PMCID: PMC7041170 DOI: 10.1186/s13024-020-00365-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 02/13/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The C9ORF72 hexanucleotide repeat expansion is the most common known genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), two fatal age-related neurodegenerative diseases. The C9ORF72 expansion encodes five dipeptide repeat proteins (DPRs) that are produced through a non-canonical translation mechanism. Among the DPRs, proline-arginine (PR), glycine-arginine (GR), and glycine-alanine (GA) are the most neurotoxic and increase the frequency of DNA double strand breaks (DSBs). While the accumulation of these genotoxic lesions is increasingly recognized as a feature of disease, the mechanism(s) of DPR-mediated DNA damage are ill-defined and the effect of DPRs on the efficiency of each DNA DSB repair pathways has not been previously evaluated. METHODS AND RESULTS Using DNA DSB repair assays, we evaluated the efficiency of specific repair pathways, and found that PR, GR and GA decrease the efficiency of non-homologous end joining (NHEJ), single strand annealing (SSA), and microhomology-mediated end joining (MMEJ), but not homologous recombination (HR). We found that PR inhibits DNA DSB repair, in part, by binding to the nucleolar protein nucleophosmin (NPM1). Depletion of NPM1 inhibited NHEJ and SSA, suggesting that NPM1 loss-of-function in PR expressing cells leads to impediments of both non-homologous and homology-directed DNA DSB repair pathways. By deleting NPM1 sub-cellular localization signals, we found that PR binds NPM1 regardless of the cellular compartment to which NPM1 was directed. Deletion of the NPM1 acidic loop motif, known to engage other arginine-rich proteins, abrogated PR and NPM1 binding. Using confocal and super-resolution immunofluorescence microscopy, we found that levels of RAD52, a component of the SSA repair machinery, were significantly increased iPSC neurons relative to isogenic controls in which the C9ORF72 expansion had been deleted using CRISPR/Cas9 genome editing. Western analysis of post-mortem brain tissues confirmed that RAD52 immunoreactivity is significantly increased in C9ALS/FTD samples as compared to controls. CONCLUSIONS Collectively, we characterized the inhibitory effects of DPRs on key DNA DSB repair pathways, identified NPM1 as a facilitator of DNA repair that is inhibited by PR, and revealed deficits in homology-directed DNA DSB repair pathways as a novel feature of C9ORF72-related disease.
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Affiliation(s)
- Nadja S. Andrade
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Biomedical Research Building Room 413, Florida, Miami 33136 USA
| | - Melina Ramic
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Biomedical Research Building Room 413, Florida, Miami 33136 USA
| | - Rustam Esanov
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Biomedical Research Building Room 413, Florida, Miami 33136 USA
| | - Wenjun Liu
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, 1600 NW 10th Ave, Miami, FL 33136 USA
| | - Mathew J. Rybin
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Biomedical Research Building Room 413, Florida, Miami 33136 USA
| | - Gabriel Gaidosh
- John P Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Miami, FL 33136 USA
- Sylvester Comprehensive Cancer Center, Biomedical Research Building, 1501 NW 10th Avenue, Miami, FL 33136 USA
| | - Abbas Abdallah
- Department of Neurology, University of Massachusetts Medical School, Worchester, MA USA
| | - Samuel Del’Olio
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Biomedical Research Building Room 413, Florida, Miami 33136 USA
| | - Tyler C. Huff
- John P Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Miami, FL 33136 USA
- Dr. John T Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, 1601 NW 12th Ave, Miami, FL. 33136 USA
| | - Nancy T. Chee
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Biomedical Research Building Room 413, Florida, Miami 33136 USA
| | - Sadhana Anatha
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Biomedical Research Building Room 413, Florida, Miami 33136 USA
| | - Tania F. Gendron
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Rd, Jacksonville, FL 32224 USA
| | - Claes Wahlestedt
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Biomedical Research Building Room 413, Florida, Miami 33136 USA
| | - Yanbin Zhang
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, 1600 NW 10th Ave, Miami, FL 33136 USA
| | - Michael Benatar
- Department of Neurology, University of Miami Miller School of Medicine, 115 NW 14th St.,, Miami, FL 33136 USA
| | - Christian Mueller
- Department of Neurology, University of Massachusetts Medical School, Worchester, MA USA
- Department of Pediatrics and Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA USA
| | - Zane Zeier
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, 1501 NW 10th Ave, Biomedical Research Building Room 413, Florida, Miami 33136 USA
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11
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Abstract
The discovery that repeat expansions in the C9orf72 gene are a frequent cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) has revolutionized our understanding of these diseases. Substantial headway has been made in characterizing C9orf72-mediated disease and unravelling its underlying aetiopathogenesis. Three main disease mechanisms have been proposed: loss of function of the C9orf72 protein and toxic gain of function from C9orf72 repeat RNA or from dipeptide repeat proteins produced by repeat-associated non-ATG translation. Several downstream processes across a range of cellular functions have also been implicated. In this article, we review the pathological and mechanistic features of C9orf72-associated FTD and ALS (collectively termed C9FTD/ALS), the model systems used to study these conditions, and the probable initiators of downstream disease mechanisms. We suggest that a combination of upstream mechanisms involving both loss and gain of function and downstream cellular pathways involving both cell-autonomous and non-cell-autonomous effects contributes to disease progression.
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Affiliation(s)
- Rubika Balendra
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK.,Department of Genetics, Evolution and Environment, Institute of Healthy Ageing, UCL, London, UK
| | - Adrian M Isaacs
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK. .,UK Dementia Research Institute at UCL, UCL Institute of Neurology, London, UK.
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12
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Sartor GC, Malvezzi AM, Kumar A, Andrade NS, Wiedner HJ, Vilca SJ, Janczura KJ, Bagheri A, Al-Ali H, Powell SK, Brown PT, Volmar CH, Foster TC, Zeier Z, Wahlestedt C. Enhancement of BDNF Expression and Memory by HDAC Inhibition Requires BET Bromodomain Reader Proteins. J Neurosci 2019; 39:612-626. [PMID: 30504275 PMCID: PMC6343644 DOI: 10.1523/jneurosci.1604-18.2018] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 10/05/2018] [Accepted: 11/11/2018] [Indexed: 02/01/2023] Open
Abstract
Histone deacetylase (HDAC) inhibitors may have therapeutic utility in multiple neurological and psychiatric disorders, but the underlying mechanisms remain unclear. Here, we identify BRD4, a BET bromodomain reader of acetyl-lysine histones, as an essential component involved in potentiated expression of brain-derived neurotrophic factor (BDNF) and memory following HDAC inhibition. In in vitro studies, we reveal that pharmacological inhibition of BRD4 reversed the increase in BDNF mRNA induced by the class I/IIb HDAC inhibitor suberoylanilide hydroxamic acid (SAHA). Knock-down of HDAC2 and HDAC3, but not other HDACs, increased BDNF mRNA expression, whereas knock-down of BRD4 blocked these effects. Using dCas9-BRD4, locus-specific targeting of BRD4 to the BDNF promoter increased BDNF mRNA. In additional studies, RGFP966, a pharmacological inhibitor of HDAC3, elevated BDNF expression and BRD4 binding to the BDNF promoter, effects that were abrogated by JQ1 (an inhibitor of BRD4). Examining known epigenetic targets of BRD4 and HDAC3, we show that H4K5ac and H4K8ac modifications and H4K5ac enrichment at the BDNF promoter were elevated following RGFP966 treatment. In electrophysiological studies, JQ1 reversed RGFP966-induced enhancement of LTP in hippocampal slice preparations. Last, in behavioral studies, RGFP966 increased subthreshold novel object recognition memory and cocaine place preference in male C57BL/6 mice, effects that were reversed by cotreatment with JQ1. Together, these data reveal that BRD4 plays a key role in HDAC3 inhibitor-induced potentiation of BDNF expression, neuroplasticity, and memory.SIGNIFICANCE STATEMENT Some histone deacetylase (HDAC) inhibitors are known to have neuroprotective and cognition-enhancing properties, but the underlying mechanisms have yet to be fully elucidated. In the current study, we reveal that BRD4, an epigenetic reader of histone acetylation marks, is necessary for enhancing brain-derived neurotrophic factor (BDNF) expression and improved memory following HDAC inhibition. Therefore, by identifying novel epigenetic regulators of BDNF expression, these data may lead to new therapeutic targets for the treatment of neuropsychiatric disorders.
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Affiliation(s)
- Gregory C Sartor
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136,
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269
| | - Andrea M Malvezzi
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Ashok Kumar
- Departments of Neuroscience and Genetics and Genomics Program, Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, Florida 32611, and
| | - Nadja S Andrade
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Hannah J Wiedner
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Samantha J Vilca
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Karolina J Janczura
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Amir Bagheri
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Hassan Al-Ali
- Miami Project to Cure Paralysis, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Samuel K Powell
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Peyton T Brown
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Claude H Volmar
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Thomas C Foster
- Departments of Neuroscience and Genetics and Genomics Program, Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, Florida 32611, and
| | - Zane Zeier
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136
| | - Claes Wahlestedt
- Center for Therapeutic Innovation and Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, Florida 33136,
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13
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Molecular Mechanisms of Neurodegeneration Related to C9orf72 Hexanucleotide Repeat Expansion. Behav Neurol 2019; 2019:2909168. [PMID: 30774737 PMCID: PMC6350563 DOI: 10.1155/2019/2909168] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/28/2018] [Accepted: 09/18/2018] [Indexed: 12/11/2022] Open
Abstract
Two clinically distinct diseases, amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), have recently been classified as two extremes of the FTD/ALS spectrum. The neuropathological correlate of FTD is frontotemporal lobar degeneration (FTLD), characterized by tau-, TDP-43-, and FUS-immunoreactive neuronal inclusions. An earlier discovery that a hexanucleotide repeat expansion mutation in chromosome 9 open reading frame 72 (C9orf72) gene causes ALS and FTD established a special subtype of ALS and FTLD with TDP-43 pathology (C9FTD/ALS). Normal individuals carry 2–10 hexanucleotide GGGGCC repeats in the C9orf72 gene, while more than a few hundred repeats represent a risk for ALS and FTD. The proposed molecular mechanisms by which C9orf72 repeat expansions induce neurodegenerative changes are C9orf72 loss-of-function through haploinsufficiency, RNA toxic gain-of-function, and gain-of-function through the accumulation of toxic dipeptide repeat proteins. However, many more cellular processes are affected by pathological processes in C9FTD/ALS, including nucleocytoplasmic transport, RNA processing, normal function of nucleolus, formation of membraneless organelles, translation, ubiquitin proteasome system, Notch signalling pathway, granule transport, and normal function of TAR DNA-binding protein 43 (TDP-43). Although the exact molecular mechanisms through which C9orf72 repeat expansions account for neurodegeneration have not been elucidated, some potential therapeutics, such as antisense oligonucleotides targeting hexanucleotide GGGGCC repeats in mRNA, were successful in preclinical trials and are awaiting phase 1 clinical trials. In this review, we critically discuss each proposed mechanism and provide insight into the most recent studies aiming to elucidate the molecular underpinnings of C9FTD/ALS.
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14
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Epigenetic mechanisms in amyotrophic lateral sclerosis: A short review. Mech Ageing Dev 2018; 174:103-110. [DOI: 10.1016/j.mad.2018.03.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 03/08/2018] [Accepted: 03/11/2018] [Indexed: 12/13/2022]
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15
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Esanov R, Andrade NS, Bennison S, Wahlestedt C, Zeier Z. The FMR1 promoter is selectively hydroxymethylated in primary neurons of fragile X syndrome patients. Hum Mol Genet 2018; 25:4870-4880. [PMID: 28173181 DOI: 10.1093/hmg/ddw311] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 08/17/2016] [Accepted: 09/02/2016] [Indexed: 12/13/2022] Open
Abstract
Fragile X syndrome (FXS) results from a repeat expansion mutation near the FMR1 gene promoter and is the most common form of heritable intellectual disability and autism. Full mutations larger than 200 CGG repeats trigger FMR1 heterochromatinization and loss of gene expression, which is primarily responsible for the pathological features of FXS . In contrast, smaller pre-mutations of 55–200 CGG are associated with FMR1 overexpression and Fragile X-associated tremor/ataxia syndrome (FXTAS), a late-onset neurodegenerative condition. While the role of 5-methylcytosine (5mC) in FMR1 gene silencing has been studied extensively, the role of 5-hydroxymethylation (5hmC), a newly discovered epigenetic mark produced through active DNA demethylation, has not been previously investigated in FXS neurons. Here, we used two complementary epigenetic assays, 5hmC sensitive restriction digest and ten-eleven translocation-assisted bisulfite pyrosequencing, to quantify FMR1 5mC and 5hmC levels. We observed increased levels of 5hmC at the FMR1 promoter in FXS patient brains with full-mutations relative to pre-mutation carriers and unaffected controls. In addition, we found that 5hmC enrichment at the FMR1 locus in FXS cells is specific to neurons by utilizing a nuclei sorting technique to separate neuronal and glial DNA fractions from post-mortem brain tissues. This FMR1 5hmC enrichment was not present in cellular models of FXS including fibroblasts, lymphocytes and reprogrammed neurons, indicating they do not fully recapitulate this epigenetic feature of disease. Future studies could investigate the potential to leverage this epigenetic pathway to restore FMR1 expression and discern whether levels of 5hmC correlate with phenotypic severity.
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Affiliation(s)
- Rustam Esanov
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Nadja S Andrade
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Sarah Bennison
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Claes Wahlestedt
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Zane Zeier
- Department of Psychiatry & Behavioral Sciences, Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL 33136, USA
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16
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Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two devastating and lethal neurodegenerative diseases seen comorbidly in up to 15% of patients. Despite several decades of research, no effective treatment or disease-modifying strategies have been developed. We now understand more than before about the genetics and biology behind ALS and FTD, but the genetic etiology for the majority of patients is still unknown and the phenotypic variability observed across patients, even those carrying the same mutation, is enigmatic. Additionally, susceptibility factors leading to neuronal vulnerability in specific central nervous system regions involved in disease are yet to be identified. As the inherited but dynamic epigenome acts as a cell-specific interface between the inherited fixed genome and both cell-intrinsic mechanisms and environmental input, adaptive epigenetic changes might contribute to the ALS/FTD aspects we still struggle to comprehend. This chapter summarizes our current understanding of basic epigenetic mechanisms, how they relate to ALS and FTD, and their potential as therapeutic targets. A clear understanding of the biological mechanisms driving these two currently incurable diseases is urgent-well-needed therapeutic strategies need to be developed soon. Disease-specific epigenetic changes have already been observed in patients and these might be central to this endeavor.
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Affiliation(s)
- Mark T W Ebbert
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Rebecca J Lank
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Veronique V Belzil
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA. .,Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada.
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17
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A C9ORF72 BAC mouse model recapitulates key epigenetic perturbations of ALS/FTD. Mol Neurodegener 2017; 12:46. [PMID: 28606110 PMCID: PMC5468954 DOI: 10.1186/s13024-017-0185-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 05/30/2017] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Amyotrophic Lateral Sclerosis (ALS) is a fatal and progressive neurodegenerative disorder with identified genetic causes representing a significant minority of all cases. A GGGGCC hexanucleotide repeat expansion (HRE) mutation within the C9ORF72 gene has recently been identified as the most frequent known cause of ALS. The expansion leads to partial heterochromatinization of the locus, yet mutant RNAs and dipeptide repeat proteins (DPRs) are still produced in sufficient quantities to confer neurotoxicity. The levels of these toxic HRE products positively correlate with cellular toxicity and phenotypic severity across multiple disease models. Moreover, the degree of epigenetic repression inversely correlates with some facets of clinical presentation in C9-ALS patients. Recently, bacterial artificial chromosomes (BAC) have been used to generate transgenic mice that harbor the HRE mutation, complementing other relevant model systems such as patient-derived induced pluripotent stem cells (iPSCs). While epigenetic features of the HRE have been investigated in various model systems and post-mortem tissues, epigenetic dysregulation at the expanded locus in C9-BAC mice remains unexplored. METHODS AND RESULTS Here, we sought to determine whether clinically relevant epigenetic perturbations caused by the HRE are mirrored in a C9-BAC mouse model. We used complementary DNA methylation assessment and immunoprecipitation methods to demonstrate that epigenetic aberrations caused by the HRE, such as DNA and histone methylation, are recapitulated in the C9-BAC mice. Strikingly, we found that cytosine hypermethylation within the promoter region of the human transgene occurred in a subset of C9-BAC mice similar to what is observed in patient populations. Moreover, we show that partial heterochromatinization of the C9 HRE occurs during the first weeks of the mouse lifespan, indicating age-dependent epigenetic repression. Using iPSC neurons, we found that preventing R-loop formation did not impede heterochromatinization of the HRE. CONCLUSIONS Taken together, these observations provide further insight into mechanism and developmental time-course of epigenetic perturbations conferred by the C9ORF72 HRE. Finally, we suggest that epigenetic repression of the C9ORF72 HRE and nearby gene promoter could impede or delay motor neuron degeneration in C9-BAC mouse models of ALS/FTD.
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18
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Emerging Epigenetic Therapies in Neuroscience: Focus on Bromodomain-Containing Drug Targets. Neuropsychopharmacology 2017; 42:374. [PMID: 27909334 PMCID: PMC5143503 DOI: 10.1038/npp.2016.203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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19
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Cohen-Hadad Y, Altarescu G, Eldar-Geva T, Levi-Lahad E, Zhang M, Rogaeva E, Gotkine M, Bartok O, Ashwal-Fluss R, Kadener S, Epsztejn-Litman S, Eiges R. Marked Differences in C9orf72 Methylation Status and Isoform Expression between C9/ALS Human Embryonic and Induced Pluripotent Stem Cells. Stem Cell Reports 2016; 7:927-940. [PMID: 27773700 PMCID: PMC5106522 DOI: 10.1016/j.stemcr.2016.09.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 09/25/2016] [Accepted: 09/26/2016] [Indexed: 02/07/2023] Open
Abstract
We established two human embryonic stem cell (hESC) lines with a GGGGCC expansion in the C9orf72 gene (C9), and compared them with haploidentical and unrelated C9 induced pluripotent stem cells (iPSCs). We found a marked difference in C9 methylation between the cells. hESCs and parental fibroblasts are entirely unmethylated while the iPSCs are hypermethylated. In addition, we show that the expansion alters promoter usage and interferes with the proper splicing of intron 1, eventually leading to the accumulation of repeat-containing mRNA following neural differentiation. These changes are attenuated in C9 iPSCs, presumably owing to hypermethylation. Altogether, this study highlights the importance of neural differentiation in the pathogenesis of disease and points to the potential role of hypermethylation as a neuroprotective mechanism against pathogenic mRNAs, envisaging a milder phenotype in C9 iPSCs. Derivation of two C9 hESC lines, haploidentical and unrelated C9 iPSCs Striking difference in C9 methylation and transcription between C9 hESCs and iPSCs Upregulation of repeat-containing mRNAs by differentiation, exclusively in C9 hESCs Supports the role for C9 methylation as a neuroprotective mechanism
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Affiliation(s)
- Yaara Cohen-Hadad
- Stem Cell Research Laboratory, Shaare Zedek Medical Center, Hebrew University School of Medicine, Jerusalem 91031, Israel
| | - Gheona Altarescu
- Zohar PGD Laboratory, Medical Genetics Institute, Shaare Zedek Medical Center, Hebrew University School of Medicine, Jerusalem 91031, Israel
| | - Talia Eldar-Geva
- IVF Unit, Shaare Zedek Medical Center, Hebrew University School of Medicine, Jerusalem 91031, Israel
| | - Ephrat Levi-Lahad
- Zohar PGD Laboratory, Medical Genetics Institute, Shaare Zedek Medical Center, Hebrew University School of Medicine, Jerusalem 91031, Israel
| | - Ming Zhang
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON MSS 3H2, Canada
| | - Ekaterina Rogaeva
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, ON MSS 3H2, Canada
| | - Marc Gotkine
- Department of Neurology, Hadassah Medical Center, Hebrew University, Jerusalem 91120, Israel
| | - Osnat Bartok
- Biological Chemistry Department, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Reut Ashwal-Fluss
- Biological Chemistry Department, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Sebastian Kadener
- Biological Chemistry Department, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Silvina Epsztejn-Litman
- Stem Cell Research Laboratory, Shaare Zedek Medical Center, Hebrew University School of Medicine, Jerusalem 91031, Israel
| | - Rachel Eiges
- Stem Cell Research Laboratory, Shaare Zedek Medical Center, Hebrew University School of Medicine, Jerusalem 91031, Israel.
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20
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ALS and FTD: an epigenetic perspective. Acta Neuropathol 2016; 132:487-502. [PMID: 27282474 DOI: 10.1007/s00401-016-1587-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 05/17/2016] [Accepted: 06/02/2016] [Indexed: 12/12/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two fatal neurodegenerative diseases seen in comorbidity in up to 50 % of cases. Despite tremendous efforts over the last two decades, no biomarkers or effective therapeutics have been identified to prevent, decelerate, or stop neuronal death in patients. While the identification of multiple mutations in more than two dozen genes elucidated the involvement of several mechanisms in the pathogenesis of both diseases, identifying the hexanucleotide repeat expansion in C9orf72, the most common genetic abnormality in ALS and FTD, opened the door to the discovery of several novel pathogenic biological routes, including chromatin remodeling and transcriptome alteration. Epigenetic processes regulate DNA replication and repair, RNA transcription, and chromatin conformation, which in turn further dictate transcriptional regulation and protein translation. Transcriptional and post-transcriptional epigenetic regulation is mediated by enzymes and chromatin-modifying complexes that control DNA methylation, histone modifications, and RNA editing. While the alteration of DNA methylation and histone modification has recently been reported in ALS and FTD, the assessment of epigenetic involvement in both diseases is still at an early stage, and the involvement of multiple epigenetic players still needs to be evaluated. As the epigenome serves as a way to alter genetic information not only during aging, but also following environmental signals, epigenetic mechanisms might play a central role in initiating ALS and FTD, especially for sporadic cases. Here, we provide a review of what is currently known about altered epigenetic processes in both ALS and FTD and discuss potential therapeutic strategies targeting epigenetic mechanisms. As approximately 85 % of ALS and FTD cases are still genetically unexplained, epigenetic therapeutics explored for other diseases might represent a profitable direction for the field.
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Mis MSC, Brajkovic S, Tafuri F, Bresolin N, Comi GP, Corti S. Development of Therapeutics for C9ORF72 ALS/FTD-Related Disorders. Mol Neurobiol 2016; 54:4466-4476. [PMID: 27349438 DOI: 10.1007/s12035-016-9993-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 06/14/2016] [Indexed: 12/13/2022]
Abstract
The identification of the hexanucleotide repeat expansion (HRE) GGGGCC (G4C2) in the non-coding region of the C9ORF72 gene as the most frequent genetic cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) has opened the path for advances in the knowledge and treatment of these disorders, which remain incurable. Recent evidence suggests that HRE RNA can cause gain-of-function neurotoxicity, but haploinsufficiency has also been hypothesized. In this review, we describe the recent developments in therapeutic targeting of the pathological expansion of C9ORF72 for ALS, FTD, and other neurodegenerative disorders. Three approaches are prominent: (1) an antisense oligonucleotides/RNA interference strategy; (2) using small compounds to counteract the toxic effects directly exerted by RNA derived from the repeat transcription (foci), by the translation of dipeptide repeat proteins (DPRs) from the repeated sequence, or by the sequestration of RNA-binding proteins from the C9ORF72 expansion; and (3) gene therapy, not only for silencing the toxic RNA/protein, but also for rescuing haploinsufficiency caused by the reduced transcription of the C9ORF72 coding sequence or by the diminished availability of RNA-binding proteins that are sequestered by RNA foci. Finally, with the perspective of clinical therapy, we discuss the most promising progress that has been achieved to date in the field.
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Affiliation(s)
- Maria Sara Cipolat Mis
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Simona Brajkovic
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Francesco Tafuri
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Nereo Bresolin
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Giacomo P Comi
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Stefania Corti
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122, Milan, Italy.
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Abstract
UNLABELLED Epigenetic processes that regulate histone acetylation play an essential role in behavioral and molecular responses to cocaine. To date, however, only a small fraction of the mechanisms involved in the addiction-associated acetylome have been investigated. Members of the bromodomain and extraterminal (BET) family of epigenetic "reader" proteins (BRD2, BRD3, BRD4, and BRDT) bind acetylated histones and serve as a scaffold for the recruitment of macromolecular complexes to modify chromatin accessibility and transcriptional activity. The role of BET proteins in cocaine-induced plasticity, however, remains elusive. Here, we used behavioral, pharmacological, and molecular techniques to examine the involvement of BET bromodomains in cocaine reward. Of the BET proteins, BRD4, but not BRD2 or BRD3, was significantly elevated in the nucleus accumbens (NAc) of mice and rats following repeated cocaine injections and self-administration. Systemic and intra-accumbal inhibition of BRD4 with the BET inhibitor, JQ1, attenuated the rewarding effects of cocaine in a conditioned place preference procedure but did not affect conditioned place aversion, nor did JQ1 alone induce conditioned aversion or preference. Investigating the underlying mechanisms, we found that repeated cocaine injections enhanced the binding of BRD4, but not BRD3, to the promoter region of Bdnf in the NAc, whereas systemic injection of JQ1 attenuated cocaine-induced expression of Bdnf in the NAc. JQ1 and siRNA-mediated knockdown of BRD4 in vitro also reduced expression of Bdnf. These findings indicate that disrupting the interaction between BET proteins and their acetylated lysine substrates may provide a new therapeutic avenue for the treatment of drug addiction. SIGNIFICANCE STATEMENT Proteins involved in the "readout" of lysine acetylation marks, referred to as BET bromodomain proteins (including BRD2, BRD3, BRD4, and BRDT), have been shown to be key regulators of chromatin dynamics and disease, and BET inhibitors are currently being studied in several clinical trials. However, their role in addiction-related phenomena remains unknown. In the current studies, we revealed that BRD4 is elevated in the nucleus accumbens and recruited to promoter regions of addiction-related genes following repeated cocaine administration, and that inhibition of BRD4 attenuates transcriptional and behavioral responses to cocaine. Together, these studies reveal that BET inhibitors may have therapeutic utility in the treatment of cocaine addiction.
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Esanov R, Belle KC, van Blitterswijk M, Belzil VV, Rademakers R, Dickson DW, Petrucelli L, Boylan KB, Dykxhoorn DM, Wuu J, Benatar M, Wahlestedt C, Zeier Z. C9orf72 promoter hypermethylation is reduced while hydroxymethylation is acquired during reprogramming of ALS patient cells. Exp Neurol 2015; 277:171-177. [PMID: 26746986 DOI: 10.1016/j.expneurol.2015.12.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 12/17/2015] [Accepted: 12/29/2015] [Indexed: 12/13/2022]
Abstract
Among several genetic mutations known to cause amyotrophic lateral sclerosis (ALS), a hexanucleotide repeat expansion in the C9orf72 gene is the most common. In approximately 30% of C9orf72-ALS cases, 5-methylcytosine (5mC) levels within the C9orf72 promoter are increased, resulting in a modestly attenuated phenotype. The developmental timing of C9orf72 promoter hypermethylation and the reason why it occurs in only a subset of patients remain unknown. In order to model the acquisition of C9orf72 hypermethylation and examine the potential role of 5-hydroxymethylcytosine (5hmC), we generated induced pluripotent stem cells (iPSCs) from an ALS patient with C9orf72 promoter hypermethylation. Our data show that 5mC levels are reduced by reprogramming and then re-acquired upon neuronal specification, while 5hmC levels increase following reprogramming and are highest in iPSCs and motor neurons. We confirmed the presence of 5hmC within the C9orf72 promoter in post-mortem brain tissues of hypermethylated patients. These findings show that iPSCs are a valuable model system for examining epigenetic perturbations caused by the C9orf72 mutation and reveal a potential role for cytosine demethylation.
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Affiliation(s)
- Rustam Esanov
- Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Kinsley C Belle
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, USA; The Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, USA
| | | | | | - Rosa Rademakers
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | | | | | - Kevin B Boylan
- Department of Neurology, Mayo Clinic, Jacksonville, FL, USA
| | - Derek M Dykxhoorn
- John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, USA; The Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, USA
| | - Joanne Wuu
- Department of Neurology, University of Miami Miller School of Medicine, USA
| | - Michael Benatar
- Department of Neurology, University of Miami Miller School of Medicine, USA
| | - Claes Wahlestedt
- Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Zane Zeier
- Center for Therapeutic Innovation, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, Miami, FL, USA.
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