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Fang M, Deibler SK, Krishnamurthy PM, Wang F, Rodriguez P, Banday S, Virbasius CM, Sena-Esteves M, Watts JK, Green MR. EZH2 inhibition reactivates epigenetically silenced FMR1 and normalizes molecular and electrophysiological abnormalities in fragile X syndrome neurons. Front Neurosci 2024; 18:1348478. [PMID: 38449737 PMCID: PMC10915284 DOI: 10.3389/fnins.2024.1348478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Accepted: 02/09/2024] [Indexed: 03/08/2024] Open
Abstract
Fragile X Syndrome (FXS) is a neurological disorder caused by epigenetic silencing of the FMR1 gene. Reactivation of FMR1 is a potential therapeutic approach for FXS that would correct the root cause of the disease. Here, using a candidate-based shRNA screen, we identify nine epigenetic repressors that promote silencing of FMR1 in FXS cells (called FMR1 Silencing Factors, or FMR1- SFs). Inhibition of FMR1-SFs with shRNAs or small molecules reactivates FMR1 in cultured undifferentiated induced pluripotent stem cells, neural progenitor cells (NPCs) and post-mitotic neurons derived from FXS patients. One of the FMR1-SFs is the histone methyltransferase EZH2, for which an FDA-approved small molecule inhibitor, EPZ6438 (also known as tazemetostat), is available. We show that EPZ6438 substantially corrects the characteristic molecular and electrophysiological abnormalities of cultured FXS neurons. Unfortunately, EZH2 inhibitors do not efficiently cross the blood-brain barrier, limiting their therapeutic use for FXS. Recently, antisense oligonucleotide (ASO)-based approaches have been developed as effective treatment options for certain central nervous system disorders. We therefore derived efficacious ASOs targeting EZH2 and demonstrate that they reactivate FMR1 expression and correct molecular and electrophysiological abnormalities in cultured FXS neurons, and reactivate FMR1 expression in human FXS NPCs engrafted within the brains of mice. Collectively, our results establish EZH2 inhibition in general, and EZH2 ASOs in particular, as a therapeutic approach for FXS.
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Affiliation(s)
- Minggang Fang
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Sara K. Deibler
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | | | - Feng Wang
- RNA Therapeutics Institute, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Paola Rodriguez
- Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Shahid Banday
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Ching-Man Virbasius
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Miguel Sena-Esteves
- Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Jonathan K. Watts
- RNA Therapeutics Institute, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Michael R. Green
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA, United States
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Liu R, Zhao E, Yu H, Yuan C, Abbas MN, Cui H. Methylation across the central dogma in health and diseases: new therapeutic strategies. Signal Transduct Target Ther 2023; 8:310. [PMID: 37620312 PMCID: PMC10449936 DOI: 10.1038/s41392-023-01528-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 05/23/2023] [Accepted: 05/25/2023] [Indexed: 08/26/2023] Open
Abstract
The proper transfer of genetic information from DNA to RNA to protein is essential for cell-fate control, development, and health. Methylation of DNA, RNAs, histones, and non-histone proteins is a reversible post-synthesis modification that finetunes gene expression and function in diverse physiological processes. Aberrant methylation caused by genetic mutations or environmental stimuli promotes various diseases and accelerates aging, necessitating the development of therapies to correct the disease-driver methylation imbalance. In this Review, we summarize the operating system of methylation across the central dogma, which includes writers, erasers, readers, and reader-independent outputs. We then discuss how dysregulation of the system contributes to neurological disorders, cancer, and aging. Current small-molecule compounds that target the modifiers show modest success in certain cancers. The methylome-wide action and lack of specificity lead to undesirable biological effects and cytotoxicity, limiting their therapeutic application, especially for diseases with a monogenic cause or different directions of methylation changes. Emerging tools capable of site-specific methylation manipulation hold great promise to solve this dilemma. With the refinement of delivery vehicles, these new tools are well positioned to advance the basic research and clinical translation of the methylation field.
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Affiliation(s)
- Ruochen Liu
- State Key Laboratory of Resource Insects, Medical Research Institute, Southwest University, Chongqing, 400715, China
- Jinfeng Laboratory, Chongqing, 401329, China
- Chongqing Engineering and Technology Research Center for Silk Biomaterials and Regenerative Medicine, Chongqing, 400716, China
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing, 400715, China
| | - Erhu Zhao
- State Key Laboratory of Resource Insects, Medical Research Institute, Southwest University, Chongqing, 400715, China
- Jinfeng Laboratory, Chongqing, 401329, China
- Chongqing Engineering and Technology Research Center for Silk Biomaterials and Regenerative Medicine, Chongqing, 400716, China
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing, 400715, China
| | - Huijuan Yu
- State Key Laboratory of Resource Insects, Medical Research Institute, Southwest University, Chongqing, 400715, China
| | - Chaoyu Yuan
- State Key Laboratory of Resource Insects, Medical Research Institute, Southwest University, Chongqing, 400715, China
| | - Muhammad Nadeem Abbas
- State Key Laboratory of Resource Insects, Medical Research Institute, Southwest University, Chongqing, 400715, China
- Jinfeng Laboratory, Chongqing, 401329, China
- Chongqing Engineering and Technology Research Center for Silk Biomaterials and Regenerative Medicine, Chongqing, 400716, China
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing, 400715, China
| | - Hongjuan Cui
- State Key Laboratory of Resource Insects, Medical Research Institute, Southwest University, Chongqing, 400715, China.
- Jinfeng Laboratory, Chongqing, 401329, China.
- Chongqing Engineering and Technology Research Center for Silk Biomaterials and Regenerative Medicine, Chongqing, 400716, China.
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing, 400715, China.
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Shah S, Sharp KJ, Raju Ponny S, Lee J, Watts JK, Berry-Kravis E, Richter JD. Antisense oligonucleotide rescue of CGG expansion-dependent FMR1 mis-splicing in fragile X syndrome restores FMRP. Proc Natl Acad Sci U S A 2023; 120:e2302534120. [PMID: 37364131 PMCID: PMC10319035 DOI: 10.1073/pnas.2302534120] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 05/26/2023] [Indexed: 06/28/2023] Open
Abstract
Aberrant alternative splicing of mRNAs results in dysregulated gene expression in multiple neurological disorders. Here, we show that hundreds of mRNAs are incorrectly expressed and spliced in white blood cells and brain tissues of individuals with fragile X syndrome (FXS). Surprisingly, the FMR1 (Fragile X Messenger Ribonucleoprotein 1) gene is transcribed in >70% of the FXS tissues. In all FMR1-expressing FXS tissues, FMR1 RNA itself is mis-spliced in a CGG expansion-dependent manner to generate the little-known FMR1-217 RNA isoform, which is comprised of FMR1 exon 1 and a pseudo-exon in intron 1. FMR1-217 is also expressed in FXS premutation carrier-derived skin fibroblasts and brain tissues. We show that in cells aberrantly expressing mis-spliced FMR1, antisense oligonucleotide (ASO) treatment reduces FMR1-217, rescues full-length FMR1 RNA, and restores FMRP (Fragile X Messenger RibonucleoProtein) to normal levels. Notably, FMR1 gene reactivation in transcriptionally silent FXS cells using 5-aza-2'-deoxycytidine (5-AzadC), which prevents DNA methylation, increases FMR1-217 RNA levels but not FMRP. ASO treatment of cells prior to 5-AzadC application rescues full-length FMR1 expression and restores FMRP. These findings indicate that misregulated RNA-processing events in blood could serve as potent biomarkers for FXS and that in those individuals expressing FMR1-217, ASO treatment may offer a therapeutic approach to mitigate the disorder.
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Affiliation(s)
- Sneha Shah
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA01605
| | - Kevin J. Sharp
- Department of Pediatrics, Rush University Medical Center, Chicago, IL60612
| | - Sithara Raju Ponny
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA01605
| | - Jonathan Lee
- RNA Therapeutics Institute, University of Massachusetts Chan Medical School, Worcester, MA01605
| | - Jonathan K. Watts
- RNA Therapeutics Institute, University of Massachusetts Chan Medical School, Worcester, MA01605
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA01605
- Li Weibo Rare Disease Institute, University of Massachusetts Chan Medical School, Worcester, MA01605
| | - Elizabeth Berry-Kravis
- Department of Pediatrics, Rush University Medical Center, Chicago, IL60612
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL60612
- Department of Anatomy and Cell Biology, Rush University Medical Center, Chicago, IL60612
| | - Joel D. Richter
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA01605
- Li Weibo Rare Disease Institute, University of Massachusetts Chan Medical School, Worcester, MA01605
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4
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Epigenetics of Autism Spectrum Disorder: Histone Deacetylases. Biol Psychiatry 2022; 91:922-933. [PMID: 35120709 DOI: 10.1016/j.biopsych.2021.11.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 11/19/2021] [Accepted: 11/22/2021] [Indexed: 01/08/2023]
Abstract
The etiology of autism spectrum disorder (ASD) remains unknown, but gene-environment interactions, mediated through epigenetic mechanisms, are thought to be a key contributing factor. Prenatal environmental factors have been shown to be associated with both increased risk of ASD and altered histone deacetylases (HDACs) or acetylation levels. The relationship between epigenetic changes and gene expression in ASD suggests that alterations in histone acetylation, which lead to changes in gene transcription, may play a key role in ASD. Alterations in the acetylome have been demonstrated for several genes in ASD, including genes involved in synaptic function, neuronal excitability, and immune responses, which are mechanisms previously implicated in ASD. We review preclinical and clinical studies that investigated HDACs and autism-associated behaviors and discuss risk genes for ASD that code for proteins associated with HDACs. HDACs are also implicated in neurodevelopmental disorders with a known genetic etiology, such as 15q11-q13 duplication and Phelan-McDermid syndrome, which share clinical features and diagnostic comorbidities (e.g., epilepsy, anxiety, and intellectual disability) with ASD. Furthermore, we highlight factors that affect the behavioral phenotype of acetylome changes, including sensitive developmental periods and brain region specificity in the context of epigenetic programming.
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Lee A, Xu J, Wen Z, Jin P. Across Dimensions: Developing 2D and 3D Human iPSC-Based Models of Fragile X Syndrome. Cells 2022; 11:1725. [PMID: 35681419 PMCID: PMC9179297 DOI: 10.3390/cells11111725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/11/2022] [Accepted: 05/13/2022] [Indexed: 02/01/2023] Open
Abstract
Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability and autism spectrum disorder. FXS is caused by a cytosine-guanine-guanine (CGG) trinucleotide repeat expansion in the untranslated region of the FMR1 gene leading to the functional loss of the gene's protein product FMRP. Various animal models of FXS have provided substantial knowledge about the disorder. However, critical limitations exist in replicating the pathophysiological mechanisms. Human induced pluripotent stem cells (hiPSCs) provide a unique means of studying the features and processes of both normal and abnormal human neurodevelopment in large sample quantities in a controlled setting. Human iPSC-based models of FXS have offered a better understanding of FXS pathophysiology specific to humans. This review summarizes studies that have used hiPSC-based two-dimensional cellular models of FXS to reproduce the pathology, examine altered gene expression and translation, determine the functions and targets of FMRP, characterize the neurodevelopmental phenotypes and electrophysiological features, and, finally, to reactivate FMR1. We also provide an overview of the most recent studies using three-dimensional human brain organoids of FXS and end with a discussion of current limitations and future directions for FXS research using hiPSCs.
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Affiliation(s)
- Azalea Lee
- Neuroscience Graduate Program, Emory University, Atlanta, GA 30322, USA;
- MD/PhD Program, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Jie Xu
- Genetics and Molecular Biology Graduate Program, Emory University, Atlanta, GA 30322, USA;
| | - Zhexing Wen
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA 30322, USA
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Peng Jin
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
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6
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Genome-wide screening for genes involved in the epigenetic basis of fragile X syndrome. Stem Cell Reports 2022; 17:1048-1058. [PMID: 35427485 PMCID: PMC9133649 DOI: 10.1016/j.stemcr.2022.03.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 11/23/2022] Open
Abstract
Fragile X syndrome (FXS), the most prevalent heritable form of intellectual disability, is caused by the transcriptional silencing of the FMR1 gene. The epigenetic factors responsible for FMR1 inactivation are largely unknown. Here, we initially demonstrated the feasibility of FMR1 reactivation by targeting a single epigenetic factor, DNMT1. Next, we established a model system for FMR1 silencing using a construct containing the FXS-related mutation upstream to a reporter gene. This construct was methylated in vitro and introduced into a genome-wide loss-of-function (LOF) library established in haploid human pluripotent stem cells (PSCs), allowing the identification of genes whose functional loss reversed the methylation-induced silencing of the FMR1 reporter. Selected candidate genes were further analyzed in haploid- and FXS-patient-derived PSCs, highlighting the epigenetic and metabolic pathways involved in FMR1 regulation. Our work sheds light on the mechanisms responsible for CGG-expansion-mediated FMR1 inactivation and offers novel targets for therapeutic FMR1 reactivation. Perturbation of a single gene, DNMT1, reactivates FMR1 in fragile X human PSCs. FX mutation containing reporter recapitulates FMR1 silencing in haploid ESCs. Genome-wide CRISPR screening reveals epigenetic modulators of FMR1 inactivation. Novel genes regulating mutated-FMR1 expression were validated in FX-iPSCs.
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7
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Hunt JFV, Li M, Risgaard R, Ananiev GE, Wildman S, Zhang F, Bugni TS, Zhao X, Bhattacharyya A. High Throughput Small Molecule Screen for Reactivation of FMR1 in Fragile X Syndrome Human Neural Cells. Cells 2021; 11:cells11010069. [PMID: 35011630 PMCID: PMC8750025 DOI: 10.3390/cells11010069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/20/2021] [Accepted: 12/22/2021] [Indexed: 11/16/2022] Open
Abstract
Fragile X syndrome (FXS) is the most common inherited cause of autism and intellectual disability. The majority of FXS cases are caused by transcriptional repression of the FMR1 gene due to epigenetic changes that are not recapitulated in current animal disease models. FXS patient induced pluripotent stem cell (iPSC)-derived gene edited reporter cell lines enable novel strategies to discover reactivators of FMR1 expression in human cells on a much larger scale than previously possible. Here, we describe the workflow using FXS iPSC-derived neural cell lines to conduct a massive, unbiased screen for small molecule activators of the FMR1 gene. The proof-of-principle methodology demonstrates the utility of human stem-cell-based methodology for the untargeted discovery of reactivators of the human FMR1 gene that can be applied to other diseases.
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Affiliation(s)
- Jack F. V. Hunt
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; (J.F.V.H.); (M.L.); (R.R.)
| | - Meng Li
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; (J.F.V.H.); (M.L.); (R.R.)
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Ryan Risgaard
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; (J.F.V.H.); (M.L.); (R.R.)
| | - Gene E. Ananiev
- Carbone Cancer Center Drug Discovery Core, University of Wisconsin-Madison, Madison, WI 53705, USA; (G.E.A.); (S.W.)
| | - Scott Wildman
- Carbone Cancer Center Drug Discovery Core, University of Wisconsin-Madison, Madison, WI 53705, USA; (G.E.A.); (S.W.)
| | - Fan Zhang
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, USA; (F.Z.); (T.S.B.)
| | - Tim S. Bugni
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, USA; (F.Z.); (T.S.B.)
| | - Xinyu Zhao
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; (J.F.V.H.); (M.L.); (R.R.)
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
- Correspondence: (X.Z.); (A.B.); Tel.: +1-(608)-263-9906 (X.Z.); +1-(608)-265-6142 (A.B.)
| | - Anita Bhattacharyya
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; (J.F.V.H.); (M.L.); (R.R.)
- Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA
- Correspondence: (X.Z.); (A.B.); Tel.: +1-(608)-263-9906 (X.Z.); +1-(608)-265-6142 (A.B.)
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8
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Sapozhnikov DM, Szyf M. Unraveling the functional role of DNA demethylation at specific promoters by targeted steric blockage of DNA methyltransferase with CRISPR/dCas9. Nat Commun 2021; 12:5711. [PMID: 34588447 PMCID: PMC8481236 DOI: 10.1038/s41467-021-25991-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 09/07/2021] [Indexed: 01/10/2023] Open
Abstract
Despite four decades of research to support the association between DNA methylation and gene expression, the causality of this relationship remains unresolved. Here, we reaffirm that experimental confounds preclude resolution of this question with existing strategies, including recently developed CRISPR/dCas9 and TET-based epigenetic editors. Instead, we demonstrate a highly effective method using only nuclease-dead Cas9 and guide RNA to physically block DNA methylation at specific targets in the absence of a confounding flexibly-tethered enzyme, thereby enabling the examination of the role of DNA demethylation per se in living cells, with no evidence of off-target activity. Using this method, we probe a small number of inducible promoters and find the effect of DNA demethylation to be small, while demethylation of CpG-rich FMR1 produces larger changes in gene expression. This method could be used to reveal the extent and nature of the contribution of DNA methylation to gene regulation.
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Affiliation(s)
- Daniel M Sapozhnikov
- Department of Pharmacology and Therapeutics, Faculty of Medicine, McGill University, Montreal, QC, Canada
| | - Moshe Szyf
- Department of Pharmacology and Therapeutics, Faculty of Medicine, McGill University, Montreal, QC, Canada.
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9
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Nakazawa T. Modeling schizophrenia with iPS cell technology and disease mouse models. Neurosci Res 2021; 175:46-52. [PMID: 34411680 DOI: 10.1016/j.neures.2021.08.002] [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: 06/21/2021] [Revised: 08/08/2021] [Accepted: 08/10/2021] [Indexed: 12/12/2022]
Abstract
Induced pluripotent stem cell (iPSC) technology, which enables the direct analysis of neuronal cells with the same genetic background as patients, has recently garnered significant attention in schizophrenia research. This technology is important because it enables a comprehensive interpretation using mice and human clinical research and cross-species verification. Here I review recent advances in modeling schizophrenia using iPSC technology, alongside the utility of disease mouse models.
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Affiliation(s)
- Takanobu Nakazawa
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, 156-8502, Japan.
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10
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Brighi C, Salaris F, Soloperto A, Cordella F, Ghirga S, de Turris V, Rosito M, Porceddu PF, D’Antoni C, Reggiani A, Rosa A, Di Angelantonio S. Novel fragile X syndrome 2D and 3D brain models based on human isogenic FMRP-KO iPSCs. Cell Death Dis 2021; 12:498. [PMID: 33993189 PMCID: PMC8124071 DOI: 10.1038/s41419-021-03776-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 04/26/2021] [Accepted: 04/28/2021] [Indexed: 02/04/2023]
Abstract
Fragile X syndrome (FXS) is a neurodevelopmental disorder, characterized by intellectual disability and sensory deficits, caused by epigenetic silencing of the FMR1 gene and subsequent loss of its protein product, fragile X mental retardation protein (FMRP). Delays in synaptic and neuronal development in the cortex have been reported in FXS mouse models; however, the main goal of translating lab research into pharmacological treatments in clinical trials has been so far largely unsuccessful, leaving FXS a still incurable disease. Here, we generated 2D and 3D in vitro human FXS model systems based on isogenic FMR1 knock-out mutant and wild-type human induced pluripotent stem cell (hiPSC) lines. Phenotypical and functional characterization of cortical neurons derived from FMRP-deficient hiPSCs display altered gene expression and impaired differentiation when compared with the healthy counterpart. FXS cortical cultures show an increased number of GFAP positive cells, likely astrocytes, increased spontaneous network activity, and depolarizing GABAergic transmission. Cortical brain organoid models show an increased number of glial cells, and bigger organoid size. Our findings demonstrate that FMRP is required to correctly support neuronal and glial cell proliferation, and to set the correct excitation/inhibition ratio in human brain development.
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Affiliation(s)
- Carlo Brighi
- grid.25786.3e0000 0004 1764 2907Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy ,grid.7841.aDepartment of Physiology and Pharmacology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy
| | - Federico Salaris
- grid.25786.3e0000 0004 1764 2907Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy ,grid.7841.aDepartment of Biology and Biotechnologies “Charles Darwin”, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy
| | - Alessandro Soloperto
- grid.25786.3e0000 0004 1764 2907Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy
| | - Federica Cordella
- grid.25786.3e0000 0004 1764 2907Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy ,grid.7841.aDepartment of Physiology and Pharmacology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy
| | - Silvia Ghirga
- grid.25786.3e0000 0004 1764 2907Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy ,grid.7841.aDepartment of Physics, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy
| | - Valeria de Turris
- grid.25786.3e0000 0004 1764 2907Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy
| | - Maria Rosito
- grid.25786.3e0000 0004 1764 2907Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy
| | - Pier Francesca Porceddu
- grid.25786.3e0000 0004 1764 2907D3 Validation Research Line, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Chiara D’Antoni
- grid.25786.3e0000 0004 1764 2907Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy ,grid.7841.aDepartment of Physiology and Pharmacology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy
| | - Angelo Reggiani
- grid.25786.3e0000 0004 1764 2907D3 Validation Research Line, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Alessandro Rosa
- grid.25786.3e0000 0004 1764 2907Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy ,grid.7841.aDepartment of Biology and Biotechnologies “Charles Darwin”, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy
| | - Silvia Di Angelantonio
- grid.25786.3e0000 0004 1764 2907Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, 00161 Rome, Italy ,grid.7841.aDepartment of Physiology and Pharmacology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy
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11
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iPSCs: A Preclinical Drug Research Tool for Neurological Disorders. Int J Mol Sci 2021; 22:ijms22094596. [PMID: 33925625 PMCID: PMC8123805 DOI: 10.3390/ijms22094596] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/24/2021] [Accepted: 04/24/2021] [Indexed: 02/07/2023] Open
Abstract
The development and commercialization of new drugs is an articulated, lengthy, and very expensive process that proceeds through several steps, starting from target identification, screening new leading compounds for testing in preclinical studies, and subsequently in clinical trials to reach the final approval for therapeutic use. Preclinical studies are usually performed using both cell cultures and animal models, although they do not completely resume the complexity of human diseases, in particular neurodegenerative conditions. To this regard, stem cells represent a powerful tool in all steps of drug discovery. The recent advancement in induced Pluripotent Stem Cells (iPSCs) technology has opened the possibility to obtain patient-specific disease models for drug screening and development. Here, we report the use of iPSCs as a disease model for drug development in the contest of neurological disorders, including Alzheimer’s (AD) and Parkinson’s disease (PD), Amyotrophic lateral Sclerosis (ALS), and Fragile X syndrome (FRAX).
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12
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Imamura K, Sakurai Y, Enami T, Shibukawa R, Nishi Y, Ohta A, Shu T, Kawaguchi J, Okada S, Hoenen T, Yasuda J, Inoue H. iPSC screening for drug repurposing identifies anti-RNA virus agents modulating host cell susceptibility. FEBS Open Bio 2021; 11:1452-1464. [PMID: 33822489 PMCID: PMC8091584 DOI: 10.1002/2211-5463.13153] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 03/15/2021] [Accepted: 03/19/2021] [Indexed: 12/12/2022] Open
Abstract
Human pathogenic RNA viruses are threats to public health because they are prone to escaping the human immune system through mutations of genomic RNA, thereby causing local outbreaks and global pandemics of emerging or re-emerging viral diseases. While specific therapeutics and vaccines are being developed, a broad-spectrum therapeutic agent for RNA viruses would be beneficial for targeting newly emerging and mutated RNA viruses. In this study, we conducted a screen of repurposed drugs using Sendai virus (an RNA virus of the family Paramyxoviridae), with human-induced pluripotent stem cells (iPSCs) to explore existing drugs that may present anti-RNA viral activity. Selected hit compounds were evaluated for their efficacy against two important human pathogens: Ebola virus (EBOV) using Huh7 cells and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using Vero E6 cells. Selective estrogen receptor modulators (SERMs), including raloxifene, exhibited antiviral activities against EBOV and SARS-CoV-2. Pioglitazone, a PPARγ agonist, also exhibited antiviral activities against SARS-CoV-2, and both raloxifene and pioglitazone presented a synergistic antiviral effect. Finally, we demonstrated that SERMs blocked entry steps of SARS-CoV-2 into host cells. These findings suggest that the identified FDA-approved drugs can modulate host cell susceptibility against RNA viruses.
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Affiliation(s)
- Keiko Imamura
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Japan.,iPSC-Based Drug Discovery and Development Team, RIKEN BioResource Research Center (BRC), Kyoto, Japan.,Medical-risk Avoidance based on iPS Cells Team, RIKEN Center for Advanced Intelligence Project (AIP), Kyoto, Japan
| | - Yasuteru Sakurai
- Department of Emerging Infectious Diseases, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Japan.,National Research Center for the Control and Prevention of Infectious Diseases (CCPID), Nagasaki University, Japan
| | - Takako Enami
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Japan.,Medical-risk Avoidance based on iPS Cells Team, RIKEN Center for Advanced Intelligence Project (AIP), Kyoto, Japan
| | - Ran Shibukawa
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Japan.,iPSC-Based Drug Discovery and Development Team, RIKEN BioResource Research Center (BRC), Kyoto, Japan
| | - Yohei Nishi
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Japan
| | - Akira Ohta
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Japan
| | | | | | - Sayaka Okada
- Department of Emerging Infectious Diseases, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Japan
| | - Thomas Hoenen
- Institute of Molecular Virology and Cell Biology, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany
| | - Jiro Yasuda
- Department of Emerging Infectious Diseases, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Japan.,National Research Center for the Control and Prevention of Infectious Diseases (CCPID), Nagasaki University, Japan
| | - Haruhisa Inoue
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Japan.,iPSC-Based Drug Discovery and Development Team, RIKEN BioResource Research Center (BRC), Kyoto, Japan.,Medical-risk Avoidance based on iPS Cells Team, RIKEN Center for Advanced Intelligence Project (AIP), Kyoto, Japan
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13
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Bayarsaikhan D, Bayarsaikhan G, Lee B. Recent advances in stem cells and gene editing: Drug discovery and therapeutics. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 181:231-269. [PMID: 34127195 DOI: 10.1016/bs.pmbts.2021.01.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The recently introduced genome editing technology has had a remarkable impact on genetic medicine. Zinc finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeat (CRISPR)/Cas nucleases are the three major platforms used for priming of stem cells or correction of mutated genes. Among these nucleases, CRISPR/Cas is the most easily applicable. Various CRISPR/Cas variants such as base editors, prime editors, mad7 nucleases, RESCUE, REPAIR, digenome sequencing, and SHERLOCK are being developed and considered as a promising tool for gene therapy and drug discovery. These advances in the CRISPR/Cas platform have enabled the correction of gene mutations from DNA to RNA level and validation of the safety of genome editing performance at a very precise level by allowing the detection of one base-pair mismatch. These promising alternatives of the CRISPR/Cas system can benefit millions of patients with intractable diseases. Although the therapeutic effects of stem cells have been confirmed in a wide range of disease models, their safety still remains an issue. Hence, scientists are concentrating on generating functionally improved stem cells by using programmable nucleases such as CRISPR. Therefore, in this chapter, we have summarized the applicable options of the CRISPR/Cas platforms by weighing their advantages and limitations in drug discovery and gene therapy.
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Affiliation(s)
- Delger Bayarsaikhan
- Lee Gil Ya Cancer and Diabetes Institute, School of Medicine, Gachon University, Incheon City, Republic of Korea
| | - Govigerel Bayarsaikhan
- Lee Gil Ya Cancer and Diabetes Institute, School of Medicine, Gachon University, Incheon City, Republic of Korea
| | - Bonghee Lee
- Lee Gil Ya Cancer and Diabetes Institute, School of Medicine, Gachon University, Incheon City, Republic of Korea.
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14
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Nobile V, Pucci C, Chiurazzi P, Neri G, Tabolacci E. DNA Methylation, Mechanisms of FMR1 Inactivation and Therapeutic Perspectives for Fragile X Syndrome. Biomolecules 2021; 11:biom11020296. [PMID: 33669384 PMCID: PMC7920310 DOI: 10.3390/biom11020296] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/04/2021] [Accepted: 02/06/2021] [Indexed: 12/13/2022] Open
Abstract
Among the inherited causes of intellectual disability and autism, Fragile X syndrome (FXS) is the most frequent form, for which there is currently no cure. In most FXS patients, the FMR1 gene is epigenetically inactivated following the expansion over 200 triplets of a CGG repeat (FM: full mutation). FMR1 encodes the Fragile X Mental Retardation Protein (FMRP), which binds several mRNAs, mainly in the brain. When the FM becomes methylated at 10-12 weeks of gestation, the FMR1 gene is transcriptionally silent. The molecular mechanisms involved in the epigenetic silencing are not fully elucidated. Among FXS families, there is a rare occurrence of males carrying a FM, which remains active because it is not methylated, thus ensuring enough FMRPs to allow for an intellectual development within normal range. Which mechanisms are responsible for sparing these individuals from being affected by FXS? In order to answer this critical question, which may have possible implications for FXS therapy, several potential epigenetic mechanisms have been described. Here, we focus on current knowledge about the role of DNA methylation and other epigenetic modifications in FMR1 gene silencing.
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Affiliation(s)
- Veronica Nobile
- Sezione di Medicina Genomica, Dipartimento Scienze della Vita e Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (V.N.); (C.P.); (P.C.); (G.N.)
| | - Cecilia Pucci
- Sezione di Medicina Genomica, Dipartimento Scienze della Vita e Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (V.N.); (C.P.); (P.C.); (G.N.)
| | - Pietro Chiurazzi
- Sezione di Medicina Genomica, Dipartimento Scienze della Vita e Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (V.N.); (C.P.); (P.C.); (G.N.)
- Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC Genetica Medica, 00168 Rome, Italy
| | - Giovanni Neri
- Sezione di Medicina Genomica, Dipartimento Scienze della Vita e Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (V.N.); (C.P.); (P.C.); (G.N.)
- Greenwood Genetic Center, JC Self Research Institute, Greenwood, SC 29646, USA
| | - Elisabetta Tabolacci
- Sezione di Medicina Genomica, Dipartimento Scienze della Vita e Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (V.N.); (C.P.); (P.C.); (G.N.)
- Correspondence: ; Tel.: +39-06-30154606
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15
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Sabitha KR, Shetty AK, Upadhya D. Patient-derived iPSC modeling of rare neurodevelopmental disorders: Molecular pathophysiology and prospective therapies. Neurosci Biobehav Rev 2020; 121:201-219. [PMID: 33370574 DOI: 10.1016/j.neubiorev.2020.12.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 12/18/2020] [Accepted: 12/19/2020] [Indexed: 12/12/2022]
Abstract
The pathological alterations that manifest during the early embryonic development due to inherited and acquired factors trigger various neurodevelopmental disorders (NDDs). Besides major NDDs, there are several rare NDDs, exhibiting specific characteristics and varying levels of severity triggered due to genetic and epigenetic anomalies. The rarity of subjects, paucity of neural tissues for detailed analysis, and the unavailability of disease-specific animal models have hampered detailed comprehension of rare NDDs, imposing heightened challenge to the medical and scientific community until a decade ago. The generation of functional neurons and glia through directed differentiation protocols for patient-derived iPSCs, CRISPR/Cas9 technology, and 3D brain organoid models have provided an excellent opportunity and vibrant resource for decoding the etiology of brain development for rare NDDs caused due to monogenic as well as polygenic disorders. The present review identifies cellular and molecular phenotypes demonstrated from patient-derived iPSCs and possible therapeutic opportunities identified for these disorders. New insights to reinforce the existing knowledge of the pathophysiology of these disorders and prospective therapeutic applications are discussed.
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Affiliation(s)
- K R Sabitha
- Centre for Molecular Neurosciences, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| | - Ashok K Shetty
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, TX, USA.
| | - Dinesh Upadhya
- Centre for Molecular Neurosciences, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India.
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16
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Cheffer A, Flitsch LJ, Krutenko T, Röderer P, Sokhranyaeva L, Iefremova V, Hajo M, Peitz M, Schwarz MK, Brüstle O. Human stem cell-based models for studying autism spectrum disorder-related neuronal dysfunction. Mol Autism 2020; 11:99. [PMID: 33308283 PMCID: PMC7733257 DOI: 10.1186/s13229-020-00383-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 09/22/2020] [Indexed: 12/13/2022] Open
Abstract
The controlled differentiation of pluripotent stem cells (PSCs) into neurons and glia offers a unique opportunity to study early stages of human central nervous system development under controlled conditions in vitro. With the advent of cell reprogramming and the possibility to generate induced pluripotent stem cells (iPSCs) from any individual in a scalable manner, these studies can be extended to a disease- and patient-specific level. Autism spectrum disorder (ASD) is considered a neurodevelopmental disorder, with substantial evidence pointing to early alterations in neurogenesis and network formation as key pathogenic drivers. For that reason, ASD represents an ideal candidate for stem cell-based disease modeling. Here, we provide a concise review on recent advances in the field of human iPSC-based modeling of syndromic and non-syndromic forms of ASD, with a particular focus on studies addressing neuronal dysfunction and altered connectivity. We further discuss recent efforts to translate stem cell-based disease modeling to 3D via brain organoid and cell transplantation approaches, which enable the investigation of disease mechanisms in a tissue-like context. Finally, we describe advanced tools facilitating the assessment of altered neuronal function, comment on the relevance of iPSC-based models for the assessment of pharmaceutical therapies and outline potential future routes in stem cell-based ASD research.
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Affiliation(s)
- Arquimedes Cheffer
- Institute of Reconstructive Neurobiology, University of Bonn Medical Faculty & University Hospital Bonn, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
| | - Lea Jessica Flitsch
- Institute of Reconstructive Neurobiology, University of Bonn Medical Faculty & University Hospital Bonn, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
| | - Tamara Krutenko
- Institute of Reconstructive Neurobiology, University of Bonn Medical Faculty & University Hospital Bonn, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
| | - Pascal Röderer
- Life & Brain GmbH, Platform Cellomics, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
| | - Liubov Sokhranyaeva
- Institute of Experimental Epileptology and Cognition Research, University of Bonn Medical Faculty & University Hospital Bonn, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
| | - Vira Iefremova
- Institute of Reconstructive Neurobiology, University of Bonn Medical Faculty & University Hospital Bonn, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
| | - Mohamad Hajo
- Institute of Reconstructive Neurobiology, University of Bonn Medical Faculty & University Hospital Bonn, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
| | - Michael Peitz
- Institute of Reconstructive Neurobiology, University of Bonn Medical Faculty & University Hospital Bonn, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
- Life & Brain GmbH, Platform Cellomics, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
- Cell Programming Core Facility, University of Bonn Medical Faculty, Bonn, Germany
| | - Martin Karl Schwarz
- Life & Brain GmbH, Platform Cellomics, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
- Institute of Experimental Epileptology and Cognition Research, University of Bonn Medical Faculty & University Hospital Bonn, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany
| | - Oliver Brüstle
- Institute of Reconstructive Neurobiology, University of Bonn Medical Faculty & University Hospital Bonn, Venusberg-Campus 1, Building 76, 53127, Bonn, Germany.
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17
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Cogram P, Alkon DL, Crockford D, Deacon RMJ, Hurley MJ, Altimiras F, Sun MK, Tranfaglia M. Chronic bryostatin-1 rescues autistic and cognitive phenotypes in the fragile X mice. Sci Rep 2020; 10:18058. [PMID: 33093534 PMCID: PMC7581799 DOI: 10.1038/s41598-020-74848-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 10/05/2020] [Indexed: 12/20/2022] Open
Abstract
Fragile X syndrome (FXS), an X-chromosome linked intellectual disability, is the leading monogenetic cause of autism spectrum disorder (ASD), a neurodevelopmental condition that currently has no specific drug treatment. Building upon the demonstrated therapeutic effects on spatial memory of bryostatin-1, a relatively specific activator of protein kinase C (PKC)ε, (also of PKCα) on impaired synaptic plasticity/maturation and spatial learning and memory in FXS mice, we investigated whether bryostatin-1 might affect the autistic phenotypes and other behaviors, including open field activity, activities of daily living (nesting and marble burying), at the effective therapeutic dose for spatial memory deficits. Further evaluation included other non-spatial learning and memory tasks. Interestingly, a short period of treatment (5 weeks) only produced very limited or no therapeutic effects on the autistic and cognitive phenotypes in the Fmr1 KO2 mice, while a longer treatment (13 weeks) with the same dose of bryostatin-1 effectively rescued the autistic and non-spatial learning deficit cognitive phenotypes. It is possible that longer-term treatment would result in further improvement in these fragile X phenotypes. This effect is clearly different from other treatment strategies tested to date, in that the drug shows little acute effect, but strong long-term effects. It also shows no evidence of tolerance, which has been a problem with other drug classes (mGluR5 antagonists, GABA-A and -B agonists). The results strongly suggest that, at appropriate dosing and therapeutic period, chronic bryostatin-1 may have great therapeutic value for both ASD and FXS.
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Affiliation(s)
- Patricia Cogram
- FRAXA-DVI, FRAXA, Santiago, Chile. .,IEB, Faculty of Science, University of Chile, Santiago, Chile.
| | | | | | - Robert M J Deacon
- FRAXA-DVI, FRAXA, Santiago, Chile.,IEB, Faculty of Science, University of Chile, Santiago, Chile
| | - Michael J Hurley
- Neuroimmunology, Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, UK
| | - Francisco Altimiras
- Faculty of Engineering, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.,Faculty of Engineering and Business, Universidad de las Américas, Santiago, Chile
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18
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Kumari D, Sciascia N, Usdin K. Small Molecules Targeting H3K9 Methylation Prevent Silencing of Reactivated FMR1 Alleles in Fragile X Syndrome Patient Derived Cells. Genes (Basel) 2020; 11:genes11040356. [PMID: 32230785 PMCID: PMC7230530 DOI: 10.3390/genes11040356] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/19/2020] [Accepted: 03/25/2020] [Indexed: 12/23/2022] Open
Abstract
In fragile X syndrome (FXS), expansion of a CGG repeat tract in the 5′-untranslated region of the FMR1 gene to >200 repeats causes transcriptional silencing by inducing heterochromatin formation. Understanding the mechanism of FMR1 silencing is important as gene reactivation is a potential treatment approach for FXS. To date, only the DNA demethylating drug 5-azadeoxycytidine (AZA) has proved effective at gene reactivation; however, this drug is toxic. The repressive H3K9 methylation mark is enriched on the FMR1 gene in FXS patient cells and is thus a potential druggable target. However, its contribution to the silencing process is unclear. Here, we studied the effect of small molecule inhibitors of H3K9 methylation on FMR1 expression in FXS patient cells. Chaetocin showed a small effect on FMR1 gene reactivation and a synergistic effect on FMR1 mRNA levels when used in combination with AZA. Additionally, chaetocin, BIX01294 and 3-Deazaneplanocin A (DZNep) were able to significantly delay the re-silencing of AZA-reactivated FMR1 alleles. These data are consistent with the idea that H3K9 methylation precedes DNA methylation and that removal of DNA methylation is necessary to see the optimal effect of histone methyl-transferase (HMT) inhibitors on FMR1 gene expression. Nonetheless, our data also show that drugs targeting repressive H3K9 methylation marks are able to produce sustained reactivation of the FMR1 gene after a single dose of AZA.
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Affiliation(s)
- Daman Kumari
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, 8 Center Drive, Bethesda, MD 20892, USA; (N.S.); (K.U.)
- Correspondence: ; Tel.: +01 301-594-5260
| | - Nicholas Sciascia
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, 8 Center Drive, Bethesda, MD 20892, USA; (N.S.); (K.U.)
- Laboratory of Genome Integrity, National Cancer Institute, Bethesda, MD 20892, USA
| | - Karen Usdin
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, 8 Center Drive, Bethesda, MD 20892, USA; (N.S.); (K.U.)
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19
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Shitik EM, Velmiskina AA, Dolskiy AA, Yudkin DV. Reactivation of FMR1 gene expression is a promising strategy for fragile X syndrome therapy. Gene Ther 2020; 27:247-253. [PMID: 32203197 DOI: 10.1038/s41434-020-0141-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Revised: 02/27/2020] [Accepted: 02/28/2020] [Indexed: 02/06/2023]
Abstract
Fragile X syndrome (FXS) is the most common form of intellectual disability and autism spectrum disorder and is caused by CGG repeat expansion in the promoter region of the FMR1 gene, which encodes fragile X mental retardation protein. This event leads to gene silencing and the loss of gene products through DNA methylation and chromatin remodeling. Due to the pathogenesis of FXS, targeted, symptomatic, and etiological approaches have been developed for its treatment. Despite their rapid development, symptomatic and targeted treatment approaches have numerous limitations; etiological approaches have the greatest potential because they affect the main causes of transcriptional silencing. In this review, we consider three potential etiological therapeutic methods that affect the reactivation of FMR1 gene expression: treatment with inhibitors of chromatin-modifying enzymes, the use of noncoding RNAs and the application of gene therapy. Inhibitors of chromatin-modifying enzymes are not clinically applicable because of their low reactivity and high cytotoxicity, and noncoding RNAs are currently only under study. Thus, we discuss gene therapy as the most promising approach for treating FXS in the near future.
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Affiliation(s)
- Ekaterina M Shitik
- State Research Center of Virology and Biotechnology "Vector", Federal Service for Surveillance on Consumer Rights Protection and Human Well-being (FBRI SRC VB "Vector", Rospotrebnadzor), Koltsovo, Novosibirsk Region, Russia
| | - Anastasia A Velmiskina
- State Research Center of Virology and Biotechnology "Vector", Federal Service for Surveillance on Consumer Rights Protection and Human Well-being (FBRI SRC VB "Vector", Rospotrebnadzor), Koltsovo, Novosibirsk Region, Russia
| | - Alexander A Dolskiy
- State Research Center of Virology and Biotechnology "Vector", Federal Service for Surveillance on Consumer Rights Protection and Human Well-being (FBRI SRC VB "Vector", Rospotrebnadzor), Koltsovo, Novosibirsk Region, Russia
| | - Dmitry V Yudkin
- State Research Center of Virology and Biotechnology "Vector", Federal Service for Surveillance on Consumer Rights Protection and Human Well-being (FBRI SRC VB "Vector", Rospotrebnadzor), Koltsovo, Novosibirsk Region, Russia.
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20
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Paulis M, Susani L, Castelli A, Suzuki T, Hara T, Straniero L, Duga S, Strina D, Mantero S, Caldana E, Sergi LS, Villa A, Vezzoni P. Chromosome Transplantation: A Possible Approach to Treat Human X-linked Disorders. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 17:369-377. [PMID: 32099849 PMCID: PMC7029378 DOI: 10.1016/j.omtm.2020.01.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 01/07/2020] [Indexed: 01/06/2023]
Abstract
Many human genetic diseases are associated with gross mutations such as aneuploidies, deletions, duplications, or inversions. For these “structural” disorders, conventional gene therapy, based on viral vectors and/or on programmable nuclease-mediated homologous recombination, is still unsatisfactory. To correct such disorders, chromosome transplantation (CT), defined as the perfect substitution of an endogenous defective chromosome with an exogenous normal one, could be applied. CT re-establishes a normal diploid cell, leaving no marker of the procedure, as we have recently shown in mouse pluripotent stem cells. To prove the feasibility of the CT approach in human cells, we used human induced pluripotent stem cells (hiPSCs) reprogrammed from Lesch-Nyhan (LN) disease patients, taking advantage of their mutation in the X-linked HPRT gene, making the LN cells selectable and distinguishable from the resistant corrected normal cells. In this study, we demonstrate, for the first time, that CT is feasible in hiPSCs: the normal exogenous X chromosome was first transferred using an improved chromosome transfer system, and the extra sex chromosome was spontaneously lost. These CT cells were functionally corrected and maintained their pluripotency and differentiation capability. By inactivation of the autologous HPRT gene, CT paves the way to the correction of hiPSCs from several X-linked disorders.
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Affiliation(s)
- Marianna Paulis
- National Research Council (CNR)-IRGB/UOS, Milan, Italy.,Humanitas Clinical and Research Center, Rozzano (MI), Italy
| | - Lucia Susani
- National Research Council (CNR)-IRGB/UOS, Milan, Italy.,Humanitas Clinical and Research Center, Rozzano (MI), Italy
| | - Alessandra Castelli
- National Research Council (CNR)-IRGB/UOS, Milan, Italy.,Humanitas Clinical and Research Center, Rozzano (MI), Italy
| | - Teruhiko Suzuki
- Stem Cell Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Takahiko Hara
- Stem Cell Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Letizia Straniero
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele (MI), Italy
| | - Stefano Duga
- Humanitas Clinical and Research Center, Rozzano (MI), Italy.,Department of Biomedical Sciences, Humanitas University, Pieve Emanuele (MI), Italy
| | - Dario Strina
- National Research Council (CNR)-IRGB/UOS, Milan, Italy.,Humanitas Clinical and Research Center, Rozzano (MI), Italy
| | - Stefano Mantero
- National Research Council (CNR)-IRGB/UOS, Milan, Italy.,Humanitas Clinical and Research Center, Rozzano (MI), Italy
| | - Elena Caldana
- National Research Council (CNR)-IRGB/UOS, Milan, Italy.,Humanitas Clinical and Research Center, Rozzano (MI), Italy
| | | | - Anna Villa
- National Research Council (CNR)-IRGB/UOS, Milan, Italy.,San Raffaele-TIGET, Milan, Italy
| | - Paolo Vezzoni
- National Research Council (CNR)-IRGB/UOS, Milan, Italy.,Humanitas Clinical and Research Center, Rozzano (MI), Italy
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21
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Freitas BC, Beltrão-Braga PCB, Marchetto MC. Modeling Inflammation on Neurodevelopmental Disorders Using Pluripotent Stem Cells. ADVANCES IN NEUROBIOLOGY 2020; 25:207-218. [PMID: 32578148 DOI: 10.1007/978-3-030-45493-7_7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Neurodevelopmental disorders (ND) are characterized by an impairment of the nervous system during its development, with a wide variety of phenotypes based on genetic or environmental cues. There are currently several disorders grouped under ND including intellectual disabilities (ID), attention-deficit hyperactivity disorder (ADHD), and autism spectrum disorders (ASD). Although NDs can have multiple culprits with varied diagnostics, several NDs present an inflammatory component. Taking advantage of induced pluripotent stem cells (iPSC), several disorders were modeled in a dish complementing in vivo data from rodent models or clinical data. Monogenic syndromes displaying ND are more feasible to be modeled using iPSCs also due to the ability to recruit patients and clinical data available. Some of these genetic disorders are Fragile X Syndrome (FXS), Rett Syndrome (RTT), and Down Syndrome (DS). Environmental NDs can be caused by maternal immune activation (MIA), such as the infection with Zika virus during pregnancy known to cause neural damage to the fetus. Our goal in this chapter is to review the advances of using stem cell research in NDs, focusing on the role of neuroinflammation on ASD and environmental NDs studies.
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Affiliation(s)
- Beatriz C Freitas
- Laboratory of Disease Modeling, Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Patricia C B Beltrão-Braga
- Laboratory of Disease Modeling, Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.,School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, SP, Brazil
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22
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Freel BA, Sheets JN, Francis KR. iPSC modeling of rare pediatric disorders. J Neurosci Methods 2019; 332:108533. [PMID: 31811832 DOI: 10.1016/j.jneumeth.2019.108533] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Revised: 11/25/2019] [Accepted: 11/27/2019] [Indexed: 12/20/2022]
Abstract
Discerning the underlying pathological mechanisms and the identification of therapeutic strategies to treat individuals affected with rare neurological diseases has proven challenging due to a host of factors. For instance, rare diseases affecting the nervous system are inherently lacking in appropriate patient sample availability compared to more common diseases, while animal models often do not accurately recapitulate specific disease phenotypes. These challenges impede research that may otherwise illuminate aspects of disease initiation and progression, leading to the ultimate identification of potential therapeutics. The establishment of induced pluripotent stem cells (iPSCs) as a human cellular model with defined genetics has provided the unique opportunity to study rare diseases within a controlled environment. iPSC models enable researchers to define mutational effects on specific cell types and signaling pathways within increasingly complex systems. Among rare diseases, pediatric diseases affecting neurodevelopment and neurological function highlight the critical need for iPSC-based disease modeling due to the inherent difficulty associated with collecting human neural tissue and the complexity of the mammalian nervous system. Rare neurodevelopmental disorders are therefore ideal candidates for utilization of iPSC-based in vitro studies. In this review, we address both the state of the iPSC field in the context of their utility and limitations for neurodevelopmental studies, as well as speculating about the future applications and unmet uses for iPSCs in rare diseases.
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Affiliation(s)
- Bethany A Freel
- Cellular Therapies and Stem Cell Biology Group, Sanford Research, Sioux Falls, SD, USA
| | - Jordan N Sheets
- Cellular Therapies and Stem Cell Biology Group, Sanford Research, Sioux Falls, SD, USA
| | - Kevin R Francis
- Cellular Therapies and Stem Cell Biology Group, Sanford Research, Sioux Falls, SD, USA; Department of Pediatrics, University of South Dakota Sanford School of Medicine, Sioux Falls, SD, USA.
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