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Tiberi J, Segatto M, Fiorenza MT, La Rosa P. Apparent Opportunities and Hidden Pitfalls: The Conflicting Results of Restoring NRF2-Regulated Redox Metabolism in Friedreich's Ataxia Pre-Clinical Models and Clinical Trials. Biomedicines 2023; 11:biomedicines11051293. [PMID: 37238963 DOI: 10.3390/biomedicines11051293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/18/2023] [Accepted: 04/22/2023] [Indexed: 05/28/2023] Open
Abstract
Friedreich's ataxia (FRDA) is an autosomal, recessive, inherited neurodegenerative disease caused by the loss of activity of the mitochondrial protein frataxin (FXN), which primarily affects dorsal root ganglia, cerebellum, and spinal cord neurons. The genetic defect consists of the trinucleotide GAA expansion in the first intron of FXN gene, which impedes its transcription. The resulting FXN deficiency perturbs iron homeostasis and metabolism, determining mitochondrial dysfunctions and leading to reduced ATP production, increased reactive oxygen species (ROS) formation, and lipid peroxidation. These alterations are exacerbated by the defective functionality of the nuclear factor erythroid 2-related factor 2 (NRF2), a transcription factor acting as a key mediator of the cellular redox signalling and antioxidant response. Because oxidative stress represents a major pathophysiological contributor to FRDA onset and progression, a great effort has been dedicated to the attempt to restore the NRF2 signalling axis. Despite this, the beneficial effects of antioxidant therapies in clinical trials only partly reflect the promising results obtained in preclinical studies conducted in cell cultures and animal models. For these reasons, in this critical review, we overview the outcomes obtained with the administration of various antioxidant compounds and critically analyse the aspects that may have contributed to the conflicting results of preclinical and clinical studies.
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Affiliation(s)
- Jessica Tiberi
- Division of Neuroscience, Department of Psychology, Sapienza University of Rome, Via dei Marsi 78, 00185 Rome, Italy
- PhD Program in Behavioral Neuroscience, Sapienza University of Rome, Via dei Marsi 78, 00185 Rome, Italy
| | - Marco Segatto
- Department of Bioscience and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Maria Teresa Fiorenza
- Division of Neuroscience, Department of Psychology, Sapienza University of Rome, Via dei Marsi 78, 00185 Rome, Italy
- European Center for Brain Research, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, 00179 Rome, Italy
| | - Piergiorgio La Rosa
- Division of Neuroscience, Department of Psychology, Sapienza University of Rome, Via dei Marsi 78, 00185 Rome, Italy
- European Center for Brain Research, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, 00179 Rome, Italy
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2
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Monfort B, Want K, Gervason S, D’Autréaux B. Recent Advances in the Elucidation of Frataxin Biochemical Function Open Novel Perspectives for the Treatment of Friedreich’s Ataxia. Front Neurosci 2022; 16:838335. [PMID: 35310092 PMCID: PMC8924461 DOI: 10.3389/fnins.2022.838335] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 01/28/2022] [Indexed: 12/25/2022] Open
Abstract
Friedreich’s ataxia (FRDA) is the most prevalent autosomic recessive ataxia and is associated with a severe cardiac hypertrophy and less frequently diabetes. It is caused by mutations in the gene encoding frataxin (FXN), a small mitochondrial protein. The primary consequence is a defective expression of FXN, with basal protein levels decreased by 70–98%, which foremost affects the cerebellum, dorsal root ganglia, heart and liver. FXN is a mitochondrial protein involved in iron metabolism but its exact function has remained elusive and highly debated since its discovery. At the cellular level, FRDA is characterized by a general deficit in the biosynthesis of iron-sulfur (Fe-S) clusters and heme, iron accumulation and deposition in mitochondria, and sensitivity to oxidative stress. Based on these phenotypes and the proposed ability of FXN to bind iron, a role as an iron storage protein providing iron for Fe-S cluster and heme biosynthesis was initially proposed. However, this model was challenged by several other studies and it is now widely accepted that FXN functions primarily in Fe-S cluster biosynthesis, with iron accumulation, heme deficiency and oxidative stress sensitivity appearing later on as secondary defects. Nonetheless, the biochemical function of FXN in Fe-S cluster biosynthesis is still debated. Several roles have been proposed for FXN: iron chaperone, gate-keeper of detrimental Fe-S cluster biosynthesis, sulfide production stimulator and sulfur transfer accelerator. A picture is now emerging which points toward a unique function of FXN as an accelerator of a key step of sulfur transfer between two components of the Fe-S cluster biosynthetic complex. These findings should foster the development of new strategies for the treatment of FRDA. We will review here the latest discoveries on the biochemical function of frataxin and the implication for a potential therapeutic treatment of FRDA.
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3
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Simna SP, Han Z. Prospects Of Non-Coding Elements In Genomic Dna Based Gene Therapy. Curr Gene Ther 2021; 22:89-103. [PMID: 33874871 DOI: 10.2174/1566523221666210419090357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 11/22/2022]
Abstract
Gene therapy has made significant development since the commencement of the first clinical trials a few decades ago and has remained a dynamic area of research regardless of obstacles such as immune response and insertional mutagenesis. Progression in various technologies like next-generation sequencing (NGS) and nanotechnology has established the importance of non-coding segments of a genome, thereby taking gene therapy to the next level. In this review, we have summarized the importance of non-coding elements, highlighting the advantages of using full-length genomic DNA loci (gDNA) compared to complementary DNA (cDNA) or minigene, currently used in gene therapy. The focus of this review is to provide an overview of the advances and the future of potential use of gDNA loci in gene therapy, expanding the therapeutic repertoire in molecular medicine.
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Affiliation(s)
- S P Simna
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC 27599. United States
| | - Zongchao Han
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC 27599. United States
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Moreno-Lorite J, Pérez-Luz S, Katsu-Jiménez Y, Oberdoerfer D, Díaz-Nido J. DNA repair pathways are altered in neural cell models of frataxin deficiency. Mol Cell Neurosci 2021; 111:103587. [PMID: 33418083 DOI: 10.1016/j.mcn.2020.103587] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 12/20/2020] [Accepted: 12/26/2020] [Indexed: 12/14/2022] Open
Abstract
Friedreich's ataxia (FRDA) is a hereditary and predominantly neurodegenerative disease caused by a deficiency of the protein frataxin (FXN). As part of the overall efforts to understand the molecular basis of neurodegeneration in FRDA, a new human neural cell line with doxycycline-induced FXN knockdown was established. This cell line, hereafter referred to as iFKD-SY, is derived from the human neuroblastoma SH-SY5Y and retains the ability to differentiate into mature neuron-like cells. In both proliferating and differentiated iFKD-SY cells, the induction of FXN deficiency is accompanied by increases in oxidative stress and DNA damage, reduced aconitase enzyme activity, higher levels of p53 and p21, activation of caspase-3, and subsequent apoptosis. More interestingly, FXN-deficient iFKD-SY cells exhibit an important transcriptional deregulation in many of the genes implicated in DNA repair pathways. The levels of some crucial proteins involved in DNA repair appear notably diminished. Furthermore, similar changes are found in two additional neural cell models of FXN deficit: primary cultures of FXN-deficient mouse neurons and human olfactory mucosa stem cells obtained from biopsies of FRDA patients. These results suggest that the deficiency of FXN leads to a down-regulation of DNA repair pathways that synergizes with oxidative stress to provoke DNA damage, which may be involved in the pathogenesis of FRDA. Thus, a failure in DNA repair may be considered a shared common molecular mechanism contributing to neurodegeneration in a number of hereditary ataxias including FRDA.
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Affiliation(s)
- Jara Moreno-Lorite
- Departamento Biología Molecular and Centro de Biología Molecular "Severo Ochoa" (UAM-CSIC), Universidad Autónoma de Madrid, 28049 Madrid, Spain; Instituto de Investigación Sanitaria Puerta de Hierro-Majadahonda (IDIPHIM), Spain
| | - Sara Pérez-Luz
- Departamento Biología Molecular and Centro de Biología Molecular "Severo Ochoa" (UAM-CSIC), Universidad Autónoma de Madrid, 28049 Madrid, Spain; Instituto de Investigación Sanitaria Puerta de Hierro-Majadahonda (IDIPHIM), Spain; Molecular Genetics Unit, Institute of Rare Diseases Research, Institute of Health Carlos III (ISCIII), Ctra. Majadahonda-Pozuelo Km2.200, 28220 Madrid, Spain.
| | - Yurika Katsu-Jiménez
- Departamento Biología Molecular and Centro de Biología Molecular "Severo Ochoa" (UAM-CSIC), Universidad Autónoma de Madrid, 28049 Madrid, Spain; Instituto de Investigación Sanitaria Puerta de Hierro-Majadahonda (IDIPHIM), Spain
| | - Daniel Oberdoerfer
- Departamento Biología Molecular and Centro de Biología Molecular "Severo Ochoa" (UAM-CSIC), Universidad Autónoma de Madrid, 28049 Madrid, Spain; Instituto de Investigación Sanitaria Puerta de Hierro-Majadahonda (IDIPHIM), Spain
| | - Javier Díaz-Nido
- Departamento Biología Molecular and Centro de Biología Molecular "Severo Ochoa" (UAM-CSIC), Universidad Autónoma de Madrid, 28049 Madrid, Spain; Instituto de Investigación Sanitaria Puerta de Hierro-Majadahonda (IDIPHIM), Spain
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Ocana-Santero G, Díaz-Nido J, Herranz-Martín S. Future Prospects of Gene Therapy for Friedreich's Ataxia. Int J Mol Sci 2021; 22:1815. [PMID: 33670433 PMCID: PMC7918362 DOI: 10.3390/ijms22041815] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/04/2021] [Accepted: 02/06/2021] [Indexed: 12/18/2022] Open
Abstract
Friedreich's ataxia is an autosomal recessive neurogenetic disease that is mainly associated with atrophy of the spinal cord and progressive neurodegeneration in the cerebellum. The disease is caused by a GAA-expansion in the first intron of the frataxin gene leading to a decreased level of frataxin protein, which results in mitochondrial dysfunction. Currently, there is no effective treatment to delay neurodegeneration in Friedreich's ataxia. A plausible therapeutic approach is gene therapy. Indeed, Friedreich's ataxia mouse models have been treated with viral vectors en-coding for either FXN or neurotrophins, such as brain-derived neurotrophic factor showing promising results. Thus, gene therapy is increasingly consolidating as one of the most promising therapies. However, several hurdles have to be overcome, including immunotoxicity and pheno-toxicity. We review the state of the art of gene therapy in Friedreich's ataxia, addressing the main challenges and the most feasible solutions for them.
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Affiliation(s)
- Gabriel Ocana-Santero
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Departamento de Biología Molecular, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain; (G.O.-S.); (J.D.-N.)
- Department of Physiology, Anatomy and Genetics, Sherrington Building, Parks Road, University of Oxford, Oxford OX1 3PT, UK
| | - Javier Díaz-Nido
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Departamento de Biología Molecular, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain; (G.O.-S.); (J.D.-N.)
| | - Saúl Herranz-Martín
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Departamento de Biología Molecular, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain; (G.O.-S.); (J.D.-N.)
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6
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Agrò M, Díaz-Nido J. Effect of Mitochondrial and Cytosolic FXN Isoform Expression on Mitochondrial Dynamics and Metabolism. Int J Mol Sci 2020; 21:E8251. [PMID: 33158039 PMCID: PMC7662637 DOI: 10.3390/ijms21218251] [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: 10/07/2020] [Revised: 10/27/2020] [Accepted: 11/02/2020] [Indexed: 02/07/2023] Open
Abstract
Friedreich's ataxia (FRDA) is a neurodegenerative disease caused by recessive mutations in the frataxin gene that lead to a deficiency of the mitochondrial frataxin (FXN) protein. Alternative forms of frataxin have been described, with different cellular localization and tissue distribution, including a cerebellum-specific cytosolic isoform called FXN II. Here, we explored the functional roles of FXN II in comparison to the mitochondrial FXN I isoform, highlighting the existence of potential cross-talk between cellular compartments. To achieve this, we transduced two human cell lines of patient and healthy subjects with lentiviral vectors overexpressing the mitochondrial or the cytosolic FXN isoforms and studied their effect on the mitochondrial network and metabolism. We confirmed the cytosolic localization of FXN isoform II in our in vitro models. Interestingly, both cytosolic and mitochondrial isoforms have an effect on mitochondrial dynamics, affecting different parameters. Accordingly, increases of mitochondrial respiration were detected after transduction with FXN I or FXN II in both cellular models. Together, these results point to the existence of a potential cross-talk mechanism between the cytosol and mitochondria, mediated by FXN isoforms. A more thorough knowledge of the mechanisms of action behind the extra-mitochondrial FXN II isoform could prove useful in unraveling FRDA physiopathology.
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Affiliation(s)
| | - Javier Díaz-Nido
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM) and Departamento de Biología Molecular, Universidad Autónoma de Madrid, Nicolás Cabrera, 1, 28049 Madrid, Spain;
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7
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Pérez-Luz S, Loria F, Katsu-Jiménez Y, Oberdoerfer D, Yang OL, Lim F, Muñoz-Blanco JL, Díaz-Nido J. Altered Secretome and ROS Production in Olfactory Mucosa Stem Cells Derived from Friedreich's Ataxia Patients. Int J Mol Sci 2020; 21:ijms21186662. [PMID: 32933002 PMCID: PMC7555998 DOI: 10.3390/ijms21186662] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 09/08/2020] [Indexed: 12/14/2022] Open
Abstract
Friedreich’s ataxia is the most common hereditary ataxia for which there is no cure or approved treatment at present. However, therapeutic developments based on the understanding of pathological mechanisms underlying the disease have advanced considerably, with the implementation of cellular models that mimic the disease playing a crucial role. Human olfactory ecto-mesenchymal stem cells represent a novel model that could prove useful due to their accessibility and neurogenic capacity. Here, we isolated and cultured these stem cells from Friedreich´s ataxia patients and healthy donors, characterizing their phenotype and describing disease-specific features such as reduced cell viability, impaired aconitase activity, increased ROS production and the release of cytokines involved in neuroinflammation. Importantly, we observed a positive effect on patient-derived cells, when frataxin levels were restored, confirming the utility of this in vitro model to study the disease. This model will improve our understanding of Friedreich´s ataxia pathogenesis and will help in developing rationally designed therapeutic strategies.
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Affiliation(s)
- Sara Pérez-Luz
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM) and Departamento de Biología Molecular, Universidad Autónoma de Madrid, Nicolás Cabrera, 1, 28049 Madrid, Spain; (S.P.-L.); (D.O.); (O.-L.Y.); (J.D.-N.)
- Molecular Genetics Unit, Institute of Rare Diseases Research, Institute of Health Carlos III (ISCIII), Ctra. Majadahonda-Pozuelo Km 2,200, 28220 Madrid, Spain
| | - Frida Loria
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM) and Departamento de Biología Molecular, Universidad Autónoma de Madrid, Nicolás Cabrera, 1, 28049 Madrid, Spain; (S.P.-L.); (D.O.); (O.-L.Y.); (J.D.-N.)
- Laboratorio de Apoyo a la Investigación, Hospital Universitario Fundación Alcorcón, Calle Budapest 1, 28922 Madrid, Spain
- Correspondence: ; Tel.: +34-911-964-594
| | - Yurika Katsu-Jiménez
- Karolinska Institutet, Department of Microbiology Tumor and Cell Biology, Solnaväjen 1, 171 77 Stockholm, Sweden;
| | - Daniel Oberdoerfer
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM) and Departamento de Biología Molecular, Universidad Autónoma de Madrid, Nicolás Cabrera, 1, 28049 Madrid, Spain; (S.P.-L.); (D.O.); (O.-L.Y.); (J.D.-N.)
| | - Oscar-Li Yang
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM) and Departamento de Biología Molecular, Universidad Autónoma de Madrid, Nicolás Cabrera, 1, 28049 Madrid, Spain; (S.P.-L.); (D.O.); (O.-L.Y.); (J.D.-N.)
| | - Filip Lim
- Department of Molecular Biology, Autonomous University of Madrid, Francisco Tomás y Valiente 7, 28049 Madrid, Spain;
| | - José Luis Muñoz-Blanco
- Department of Neurology, Hospital Universitario Gregorio Marañón, Dr. Esquerdo 46, 28007 Madrid, Spain;
| | - Javier Díaz-Nido
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM) and Departamento de Biología Molecular, Universidad Autónoma de Madrid, Nicolás Cabrera, 1, 28049 Madrid, Spain; (S.P.-L.); (D.O.); (O.-L.Y.); (J.D.-N.)
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8
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Fernández-Frías I, Pérez-Luz S, Díaz-Nido J. Analysis of Putative Epigenetic Regulatory Elements in the FXN Genomic Locus. Int J Mol Sci 2020; 21:E3410. [PMID: 32408537 PMCID: PMC7279236 DOI: 10.3390/ijms21103410] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 05/05/2020] [Accepted: 05/09/2020] [Indexed: 12/22/2022] Open
Abstract
Friedreich´s ataxia (FRDA) is an autosomal recessive disease caused by an abnormally expanded Guanine-Adenine-Adenine (GAA) repeat sequence within the first intron of the frataxin gene (FXN). The molecular mechanisms associated with FRDA are still poorly understood and most studies on FXN gene regulation have been focused on the region around the minimal promoter and the region in which triplet expansion occurs. Nevertheless, since there could be more epigenetic changes involved in the reduced levels of FXN transcripts, the aim of this study was to obtain a more detailed view of the possible regulatory elements by analyzing data from ENCODE and Roadmap consortia databases. This bioinformatic analysis indicated new putative regulatory regions within the FXN genomic locus, including exons, introns, and upstream and downstream regions. Moreover, the region next to the end of intron 4 is of special interest, since the enhancer signals in FRDA-affected tissues are weak or absent in this region, whilst they are strong in the rest of the analyzed tissues. Therefore, these results suggest that there could be a direct relationship between the absence of enhancer sequences in this specific region and their predisposition to be affected in this pathology.
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Affiliation(s)
- Iván Fernández-Frías
- Departamento Biología Molecular and Centro de Biología Molecular “Severo Ochoa” (UAM-CSIC), Universidad Autónoma de Madrid, 28049 Madrid, Spain; (I.F.-F.); (J.D.-N.)
- Instituto Investigación Sanitaria Puerta de Hierro-Majadahonda, 28222 Madrid, Spain
| | - Sara Pérez-Luz
- Departamento Biología Molecular and Centro de Biología Molecular “Severo Ochoa” (UAM-CSIC), Universidad Autónoma de Madrid, 28049 Madrid, Spain; (I.F.-F.); (J.D.-N.)
- Instituto Investigación Sanitaria Puerta de Hierro-Majadahonda, 28222 Madrid, Spain
| | - Javier Díaz-Nido
- Departamento Biología Molecular and Centro de Biología Molecular “Severo Ochoa” (UAM-CSIC), Universidad Autónoma de Madrid, 28049 Madrid, Spain; (I.F.-F.); (J.D.-N.)
- Instituto Investigación Sanitaria Puerta de Hierro-Majadahonda, 28222 Madrid, Spain
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Enhanced Production of Herpes Simplex Virus 1 Amplicon Vectors by Gene Modification and Optimization of Packaging Cell Growth Medium. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 17:491-496. [PMID: 32258212 PMCID: PMC7114837 DOI: 10.1016/j.omtm.2020.03.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 03/10/2020] [Indexed: 01/25/2023]
Abstract
Herpes simplex virus 1 (HSV-1)-derived amplicon vectors are unique in their ability to accommodate large DNA molecules allowing whole genomic loci to be included with all of their regulatory elements. Additional advantages of these amplicons include their minimal toxicity and ability to persist as episomes, with negligible risk of insertional mutagenesis, being particularly well-suited for gene therapy of neurological disorders due to their outstanding ability to deliver genes into neurons and other neural cells. However, extensive gene therapy application has been hindered by difficulties in vector production. This work improved HSV-1 amplicons production by genetic modification of the packaging cell line and optimization of the culture medium. A stably-transfected Vero 2-2 cell line overexpressing the anti-apoptotic Bcl-2 protein was generated, exhibiting an increased resistance to apoptosis, prolonged culture duration, and a significant improvement in viral vector production. Additionally, supplementation of the growth medium with antioxidants, polyamines, amino acids, and reduced glutathione further increased the yield of packaged amplicon vectors. With these modifications, HSV-1 amplicons could be isolated from culture supernatants instead of cell lysates, leading to vector preparations with higher titer and purity and paving the way for generation of stable cell lines that are capable of continuous herpesviral vector production.
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10
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Zheng M, Mitra RN, Weiss ER, Han Z. Rhodopsin Genomic Loci DNA Nanoparticles Improve Expression and Rescue of Retinal Degeneration in a Model for Retinitis Pigmentosa. Mol Ther 2019; 28:523-535. [PMID: 31879189 DOI: 10.1016/j.ymthe.2019.11.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 11/12/2019] [Accepted: 11/21/2019] [Indexed: 02/07/2023] Open
Abstract
The use of gene therapy may allow replacement of the defective gene. Minigenes, such as cDNAs, are often used. However, these may not express normal physiological genetic profiles due to lack of crucial endogenous regulatory elements. We constructed DNA nanoparticles (NPs) that contain either the mouse or human full-length rhodopsin genomic locus, including endogenous promoters, all introns, and flanking regulatory sequences of the 15-16 kb genomic rhodopsin DNA inserts. We transduced the NPs into primary retinal cell cultures from the rhodopsin knockout (RKO) mouse in vitro and into the RKO mouse in vivo and compared the effects on different functions to plasmid cDNA NP counterparts that were driven by ubiquitous promoters. Our results demonstrate that genomic DNA vectors resulted in long-term high levels of physiological transgene expression over a period of 5 months. In contrast, the cDNA counterparts exhibited low levels of expression with sensitivity to the endoplasmic reticulum (ER) stress mechanism using the same transgene copy number both in vitro and in vivo. This study demonstrates for the first time the transducing of the rhodopsin genomic locus using compacted DNA NPs.
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Affiliation(s)
- Min Zheng
- Department of Ophthalmology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Rajendra N Mitra
- Department of Ophthalmology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Ellen R Weiss
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Zongchao Han
- Department of Ophthalmology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Division of Pharmacoengineering & Molecular Pharmaceutics, Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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11
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Bon C, Luffarelli R, Russo R, Fortuni S, Pierattini B, Santulli C, Fimiani C, Persichetti F, Cotella D, Mallamaci A, Santoro C, Carninci P, Espinoza S, Testi R, Zucchelli S, Condò I, Gustincich S. SINEUP non-coding RNAs rescue defective frataxin expression and activity in a cellular model of Friedreich's Ataxia. Nucleic Acids Res 2019; 47:10728-10743. [PMID: 31584077 PMCID: PMC6847766 DOI: 10.1093/nar/gkz798] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 08/08/2019] [Accepted: 09/28/2019] [Indexed: 12/16/2022] Open
Abstract
Friedreich's ataxia (FRDA) is an untreatable disorder with neuro- and cardio-degenerative progression. This monogenic disease is caused by the hyper-expansion of naturally occurring GAA repeats in the first intron of the FXN gene, encoding for frataxin, a protein implicated in the biogenesis of iron-sulfur clusters. As the genetic defect interferes with FXN transcription, FRDA patients express a normal frataxin protein but at insufficient levels. Thus, current therapeutic strategies are mostly aimed to restore physiological FXN expression. We have previously described SINEUPs, natural and synthetic antisense long non-coding RNAs, which promote translation of partially overlapping mRNAs through the activity of an embedded SINEB2 domain. Here, by in vitro screening, we have identified a number of SINEUPs targeting human FXN mRNA and capable to up-regulate frataxin protein to physiological amounts acting at the post-transcriptional level. Furthermore, FXN-specific SINEUPs promote the recovery of disease-associated mitochondrial aconitase defects in FRDA-derived cells. In summary, we provide evidence that SINEUPs may be the first gene-specific therapeutic approach to activate FXN translation in FRDA and, more broadly, a novel scalable platform to develop new RNA-based therapies for haploinsufficient diseases.
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Affiliation(s)
- Carlotta Bon
- Central RNA Laboratory, Istituto Italiano di Tecnologia (IIT), Genova, Italy
- Area of Neuroscience, International School for Advanced Studies (SISSA), Italy
| | - Riccardo Luffarelli
- Department of Biomedicine and Prevention, Laboratory of Signal Transduction, University of Rome Tor Vergata, Rome, Italy
| | - Roberta Russo
- Area of Neuroscience, International School for Advanced Studies (SISSA), Italy
| | - Silvia Fortuni
- Department of Biomedicine and Prevention, Laboratory of Signal Transduction, University of Rome Tor Vergata, Rome, Italy
| | - Bianca Pierattini
- Central RNA Laboratory, Istituto Italiano di Tecnologia (IIT), Genova, Italy
- Area of Neuroscience, International School for Advanced Studies (SISSA), Italy
| | - Chiara Santulli
- Area of Neuroscience, International School for Advanced Studies (SISSA), Italy
| | - Cristina Fimiani
- Area of Neuroscience, International School for Advanced Studies (SISSA), Italy
| | - Francesca Persichetti
- Department of Health Sciences and Interdisciplinary Research Center of Autoimmune Diseases (IRCAD), University of Piemonte Orientale (UPO), Novara, Italy
| | - Diego Cotella
- Department of Health Sciences and Interdisciplinary Research Center of Autoimmune Diseases (IRCAD), University of Piemonte Orientale (UPO), Novara, Italy
| | - Antonello Mallamaci
- Area of Neuroscience, International School for Advanced Studies (SISSA), Italy
| | - Claudio Santoro
- Department of Health Sciences and Interdisciplinary Research Center of Autoimmune Diseases (IRCAD), University of Piemonte Orientale (UPO), Novara, Italy
| | - Piero Carninci
- RIKEN Center for Life Science Technologies, Division of Genomic Technologies, Yokohama, Kanagawa, Japan
| | - Stefano Espinoza
- Central RNA Laboratory, Istituto Italiano di Tecnologia (IIT), Genova, Italy
| | - Roberto Testi
- Department of Biomedicine and Prevention, Laboratory of Signal Transduction, University of Rome Tor Vergata, Rome, Italy
| | - Silvia Zucchelli
- Area of Neuroscience, International School for Advanced Studies (SISSA), Italy
- Department of Health Sciences and Interdisciplinary Research Center of Autoimmune Diseases (IRCAD), University of Piemonte Orientale (UPO), Novara, Italy
| | - Ivano Condò
- Department of Biomedicine and Prevention, Laboratory of Signal Transduction, University of Rome Tor Vergata, Rome, Italy
| | - Stefano Gustincich
- Central RNA Laboratory, Istituto Italiano di Tecnologia (IIT), Genova, Italy
- Area of Neuroscience, International School for Advanced Studies (SISSA), Italy
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12
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Weng L, Wang Q, Yu S, Yang X, Lynch DR, Mesaros C, Blair IA. Evaluation of antibodies for western blot analysis of frataxin protein isoforms. J Immunol Methods 2019; 474:112629. [PMID: 31279523 PMCID: PMC6829029 DOI: 10.1016/j.jim.2019.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 05/21/2019] [Accepted: 07/03/2019] [Indexed: 12/12/2022]
Abstract
Frataxin is the protein that is down-regulated in Friedreich ataxia (FRDA), an autosomal recessive genetic disease caused by an intronic GAA repeat expansion in intron-1 of the FXN gene. The GAA repeats result in epigenetic silencing of the FXN gene and reduced expression of the cytosolic full-length frataxin (1-210) protein. Full length frataxin translocates to the mitochondria, leading to formation of mature frataxin (81-210) formed by cleavage of the mitochondrial targeting sequence at K-80 of the full-length protein. There are currently no approved treatments for FRDA, although experimental approaches involving up-regulation or replacement of mature frataxin protein through numerous approaches are being tested. Many of the pre-clinical studies of these experimental approaches are conducted in mouse and monkey models as well as in human cell lines. Consequently, well-validated antibodies are required for use in western blot analysis to determine whether levels of various forms of frataxin have been increased. Here we examined the specificity of five commercially available anti-frataxin antibodies and determined whether they detect mature frataxin in mouse heart tissue. Four protein standards of monkey, human, and mouse frataxin as well as mouse heart tissue were examined using polyacrylamide gel electrophoresis (PAGE) in combination with western blot analysis. One antibody failed to detect any of the frataxin standards or endogenous frataxin in mouse heart tissue. Three of the antibodies detected a protein in mouse heart tissue that ran slightly faster on PAGE (at 23.4 kDa) to that predicted for full-length frataxin (23.9 kDa). One antibody detected all four frataxin standards as well as endogenous mouse mature frataxin in mouse tissue. Significantly, this antibody, which will be useful for monitoring mature frataxin levels in monkey, human, and mouse tissues, did not detect a protein in mouse heart tissue at 23.4 kDa. Therefore, antibodies detecting the immunoreactive protein at 23.4 kDa could be misleading when testing for the up-regulation of frataxin in animal models.
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Affiliation(s)
- Liwei Weng
- Penn/CHOP Center of Excellence in Friedreich's Ataxia, University of Pennsylvania, Philadelphia, PA 19104, USA; Penn SRP Center and Center of Excellence in Environmental Toxicology, Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Qingqing Wang
- Penn/CHOP Center of Excellence in Friedreich's Ataxia, University of Pennsylvania, Philadelphia, PA 19104, USA; Penn SRP Center and Center of Excellence in Environmental Toxicology, Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sixiang Yu
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Xiaolu Yang
- Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David R Lynch
- Penn/CHOP Center of Excellence in Friedreich's Ataxia, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Pediatrics and Neurology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Clementina Mesaros
- Penn/CHOP Center of Excellence in Friedreich's Ataxia, University of Pennsylvania, Philadelphia, PA 19104, USA; Penn SRP Center and Center of Excellence in Environmental Toxicology, Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ian A Blair
- Penn/CHOP Center of Excellence in Friedreich's Ataxia, University of Pennsylvania, Philadelphia, PA 19104, USA; Penn SRP Center and Center of Excellence in Environmental Toxicology, Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Cancer Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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13
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Abstract
Friedreich's ataxia (FRDA) is a degenerative disease that affects both the central and the peripheral nervous systems and non-neural tissues including, mainly, heart, and endocrine pancreas. It is an autosomal recessive disease caused by a GAA triplet-repeat localized within an Alu sequence element in intron 1 of frataxin (FXN) gene, which encodes a mitochondrial protein FXN. This protein is essential for mitochondrial function by the involvement of iron-sulfur cluster biogenesis. The effects of its deficiency also include disruption of cellular, particularly mitochondrial, iron homeostasis, i.e., relatively more iron accumulated in mitochondria and less iron presented in cytosol. Though iron toxicity is commonly thought to be mediated via Fenton reaction, oxidative stress seems not to be the main problem to result in detrimental effects on cell survival, particularly neuron survival. Therefore, the basic research on FXN function is urgently demanded to understand the disease. This chapter focuses on the outcome of FXN expression, regulation, and function in cellular or animal models of FRDA and on iron pathophysiology in the affected tissues. Finally, therapeutic strategies based on the control of iron toxicity and iron cellular redistribution are considered. The combination of multiple therapeutic targets including iron, oxidative stress, mitochondrial function, and FXN regulation is also proposed.
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Affiliation(s)
- Kuanyu Li
- Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, Nanjing, 210093, People's Republic of China.
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14
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Guo L, Wang Q, Weng L, Hauser LA, Strawser CJ, Mesaros C, Lynch DR, Blair IA. Characterization of a new N-terminally acetylated extra-mitochondrial isoform of frataxin in human erythrocytes. Sci Rep 2018; 8:17043. [PMID: 30451920 PMCID: PMC6242848 DOI: 10.1038/s41598-018-35346-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 11/02/2018] [Indexed: 01/18/2023] Open
Abstract
Frataxin is a highly conserved protein encoded by the frataxin (FXN) gene. The full-length 210-amino acid form of protein frataxin (1-210; isoform A) expressed in the cytosol of cells rapidly translocates to the mitochondria, where it is converted to the mature form (81-210) by mitochondrial processing peptidase. Mature frataxin (81-210) is a critically important protein because it facilitates the assembly of mitochondrial iron-sulfur cluster protein complexes such as aconitase, lipoate synthase, and succinate dehydrogenases. Decreased expression of frataxin protein is responsible for the devastating rare genetic disease of Friedreich's ataxia. The mitochondrial form of frataxin has long been thought to be present in erythrocytes even though paradoxically, erythrocytes lack mitochondria. We have discovered that erythrocyte frataxin is in fact a novel isoform of frataxin (isoform E) with 135-amino acids and an N-terminally acetylated methionine residue. There is three times as much isoform E in erythrocytes (20.9 ± 6.4 ng/mL) from the whole blood of healthy volunteers (n = 10) when compared with the mature mitochondrial frataxin present in other blood cells (7.1 ± 1.0 ng/mL). Isoform E lacks a mitochondrial targeting sequence and so is distributed to both cytosol and the nucleus when expressed in cultured cells. When extra-mitochondrial frataxin isoform E is expressed in HEK 293 cells, it is converted to a shorter isoform identical to the mature frataxin found in mitochondria, which raises the possibility that it is involved in disease etiology. The ability to specifically quantify extra-mitochondrial and mitochondrial isoforms of frataxin in whole blood will make it possible to readily follow the natural history of diseases such as Friedreich's ataxia and monitor the efficacy of therapeutic interventions.
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Affiliation(s)
- Lili Guo
- Penn SRP Center and Center of Excellence in Environmental Toxicology Center, Department of Systems Pharmacology and Translational Therapeutics Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, United States
- Penn/CHOP Center of Excellence in Friedreich's ataxia, Philadelphia, PA, 19104, United States
| | - Qingqing Wang
- Penn SRP Center and Center of Excellence in Environmental Toxicology Center, Department of Systems Pharmacology and Translational Therapeutics Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, United States
- Penn/CHOP Center of Excellence in Friedreich's ataxia, Philadelphia, PA, 19104, United States
| | - Liwei Weng
- Penn SRP Center and Center of Excellence in Environmental Toxicology Center, Department of Systems Pharmacology and Translational Therapeutics Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, United States
| | - Lauren A Hauser
- Penn/CHOP Center of Excellence in Friedreich's ataxia, Philadelphia, PA, 19104, United States
- Departments of Pediatrics and Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, United States
- Departments of Pediatrics and Neurology Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, United States
| | - Cassandra J Strawser
- Penn/CHOP Center of Excellence in Friedreich's ataxia, Philadelphia, PA, 19104, United States
- Departments of Pediatrics and Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, United States
- Departments of Pediatrics and Neurology Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, United States
| | - Clementina Mesaros
- Penn SRP Center and Center of Excellence in Environmental Toxicology Center, Department of Systems Pharmacology and Translational Therapeutics Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, United States
- Penn/CHOP Center of Excellence in Friedreich's ataxia, Philadelphia, PA, 19104, United States
| | - David R Lynch
- Penn/CHOP Center of Excellence in Friedreich's ataxia, Philadelphia, PA, 19104, United States
- Departments of Pediatrics and Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, United States
- Departments of Pediatrics and Neurology Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, United States
| | - Ian A Blair
- Penn SRP Center and Center of Excellence in Environmental Toxicology Center, Department of Systems Pharmacology and Translational Therapeutics Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, United States.
- Penn/CHOP Center of Excellence in Friedreich's ataxia, Philadelphia, PA, 19104, United States.
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15
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Ventosa M, Wu Z, Lim F. Sustained FXN expression in dorsal root ganglia from a nonreplicative genomic HSV-1 vector. J Gene Med 2017; 19:376-386. [PMID: 29044877 DOI: 10.1002/jgm.2993] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 10/06/2017] [Accepted: 10/07/2017] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Friedreich's ataxia (FA) is an autosomal recessive neurodegenerative disease caused by mutations in the frataxin gene (FXN), which lead to reduced levels of the essential mitochondrial protein frataxin. Currently, there is no effective cure. METHODS With the aim of developing a gene therapy for FA neuropathology, we describe the construction and preliminary characterization of a high-capacity nonreplicative genomic herpes simplex virus type 1 vector (H24B-FXNlac vector) carrying a reduced version of the human FXN genomic locus, comprising the 5-kb promoter and the FXN cDNA with the inclusion of intron 1. RESULTS We show that the transgene cassette contains the elements necessary to preserve physiological neuronal regulation of human FXN expression. Transduction of cultured fetal rat dorsal root ganglia neurons with the H24B-FXNlac vector results in sustained expression of human FXN transcripts and frataxin protein. Rat footpad inoculation with the H24B-FXNlac vector results in human FXN transgene delivery to the dorsal root ganglia, with expression persisting for at least 1 month. CONCLUSIONS The results of the present study support the feasibility of using this vector for sustained neuronal expression of human frataxin for FA gene therapy.
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Affiliation(s)
- Maria Ventosa
- Department of Neurosurgery, University of Michigan and VA Ann Arbor Healthcare System, Ann Arbor, MI, USA
| | - Zetang Wu
- Department of Neurology, University of Michigan and VA Ann Arbor Healthcare System, Ann Arbor, MI, USA
| | - Filip Lim
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Madrid, Spain
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16
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Rocca CJ, Goodman SM, Dulin JN, Haquang JH, Gertsman I, Blondelle J, Smith JLM, Heyser CJ, Cherqui S. Transplantation of wild-type mouse hematopoietic stem and progenitor cells ameliorates deficits in a mouse model of Friedreich's ataxia. Sci Transl Med 2017; 9:eaaj2347. [PMID: 29070698 PMCID: PMC5735830 DOI: 10.1126/scitranslmed.aaj2347] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 01/31/2017] [Accepted: 06/13/2017] [Indexed: 12/14/2022]
Abstract
Friedreich's ataxia (FRDA) is an incurable autosomal recessive neurodegenerative disease caused by reduced expression of the mitochondrial protein frataxin due to an intronic GAA-repeat expansion in the FXN gene. We report the therapeutic efficacy of transplanting wild-type mouse hematopoietic stem and progenitor cells (HSPCs) into the YG8R mouse model of FRDA. In the HSPC-transplanted YG8R mice, development of muscle weakness and locomotor deficits was abrogated as was degeneration of large sensory neurons in the dorsal root ganglia (DRGs) and mitochondrial capacity was improved in brain, skeletal muscle, and heart. Transplanted HSPCs engrafted and then differentiated into microglia in the brain and spinal cord and into macrophages in the DRGs, heart, and muscle of YG8R FRDA mice. We observed the transfer of wild-type frataxin and Cox8 mitochondrial proteins from HSPC-derived microglia/macrophages to FRDA mouse neurons and muscle myocytes in vivo. Our results show the HSPC-mediated phenotypic rescue of FRDA in YG8R mice and suggest that this approach should be investigated further as a strategy for treating FRDA.
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Affiliation(s)
- Celine J Rocca
- Division of Genetics, Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Spencer M Goodman
- Division of Genetics, Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jennifer N Dulin
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Joseph H Haquang
- Division of Genetics, Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Ilya Gertsman
- Division of Genetics, Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jordan Blondelle
- Division of Cardiovascular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Janell L M Smith
- Division of Genetics, Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Charles J Heyser
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Stephanie Cherqui
- Division of Genetics, Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA.
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17
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Zhao H, Li H, Hao S, Chen J, Wu J, Song C, Zhang M, Qiao T, Li K. Peptide SS-31 upregulates frataxin expression and improves the quality of mitochondria: implications in the treatment of Friedreich ataxia. Sci Rep 2017; 7:9840. [PMID: 28852135 PMCID: PMC5575096 DOI: 10.1038/s41598-017-10320-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 08/01/2017] [Indexed: 12/11/2022] Open
Abstract
Friedreich ataxia is a progressive neurodegenerative disease caused by the expansion of GAA trinucleotide repeats within the first intron of the FXN gene, which encodes frataxin. The pathophysiology of the disease is thought to be derived from the decrease of Fe-S cluster biogenesis due to frataxin deficiency. There is currently no effective treatment for the disease. In our study, we demonstrated that treatment with the mitochondrion-targeted peptide SS-31 reduced frataxin deficiency-induced oxidative stress in lymphoblasts and fibroblasts derived from patients. Interestingly, SS-31 treatment translationally upregulated the protein level of frataxin in a dose-dependent manner. Furthermore, SS-31 treatment increased the enzymatic activities of the iron-sulphur enzymes, including aconitase and complex II and III of the respiratory chain. Further evaluation of the quality of mitochondria showed that mitochondrial membrane potential, ATP content, NAD+/NADH, and the morphology of mitochondria all improved. Our results suggest that SS-31 might potentially be a new drug for the early treatment of Friedreich ataxia.
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Affiliation(s)
- Hongting Zhao
- Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, 210093, Nanjing, P. R. China
| | - Huihui Li
- Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, 210093, Nanjing, P. R. China
| | - Shuangying Hao
- Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, 210093, Nanjing, P. R. China
- Medical School of Henan Polytechnic University, 454000, Jiaozuo, P. R. China
| | - Jiping Chen
- Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, 210093, Nanjing, P. R. China
| | - Jing Wu
- Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, 210093, Nanjing, P. R. China
| | - Chuanhui Song
- Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, 210093, Nanjing, P. R. China
| | - Meng Zhang
- Department of Vascular Surgery, Drum Tower Clinical Medical College of Nanjing Medical University, Nanjing, P. R. China
| | - Tong Qiao
- Department of Vascular Surgery, Drum Tower Clinical Medical College of Nanjing Medical University, Nanjing, P. R. China
| | - Kuanyu Li
- Jiangsu Key Laboratory of Molecular Medicine, Medical School of Nanjing University, 210093, Nanjing, P. R. China.
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18
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Katsu-Jiménez Y, Loría F, Corona JC, Díaz-Nido J. Gene Transfer of Brain-derived Neurotrophic Factor (BDNF) Prevents Neurodegeneration Triggered by FXN Deficiency. Mol Ther 2016; 24:877-89. [PMID: 26849417 PMCID: PMC4881769 DOI: 10.1038/mt.2016.32] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 01/21/2016] [Indexed: 02/07/2023] Open
Abstract
Friedreich's ataxia is a predominantly neurodegenerative disease caused by recessive mutations that produce a deficiency of frataxin (FXN). Here, we have used a herpesviral amplicon vector carrying a gene encoding for brain-derived neurotrophic factor (BDNF) to drive its overexpression in neuronal cells and test for its effect on FXN-deficient neurons both in culture and in the mouse cerebellum in vivo. Gene transfer of BDNF to primary cultures of mouse neurons prevents the apoptosis which is triggered by the knockdown of FXN gene expression. This neuroprotective effect of BDNF is also observed in vivo in a viral vector-based knockdown mouse cerebellar model. The injection of a lentiviral vector carrying a minigene encoding for a FXN-specific short hairpin ribonucleic acid (shRNA) into the mouse cerebellar cortex triggers a FXN deficit which is accompanied by significant apoptosis of granule neurons as well as loss of calbindin in Purkinje cells. These pathological changes are accompanied by a loss of motor coordination of mice as assayed by the rota-rod test. Coinjection of a herpesviral vector encoding for BDNF efficiently prevents both the development of cerebellar neuropathology and the ataxic phenotype. These data demonstrate the potential therapeutic usefulness of neurotrophins like BDNF to protect FXN-deficient neurons from degeneration.
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Affiliation(s)
- Yurika Katsu-Jiménez
- Centro de Biología Molecular Severo Ochoa (UAM-CSIC) and Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Instituto de Investigaciones Sanitarias Hospital Puerta de Hierro-Majadahonda (IDIPHIM), Madrid, Spain
| | - Frida Loría
- Centro de Biología Molecular Severo Ochoa (UAM-CSIC) and Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Instituto de Investigaciones Sanitarias Hospital Puerta de Hierro-Majadahonda (IDIPHIM), Madrid, Spain
| | - Juan Carlos Corona
- Centro de Biología Molecular Severo Ochoa (UAM-CSIC) and Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Instituto de Investigaciones Sanitarias Hospital Puerta de Hierro-Majadahonda (IDIPHIM), Madrid, Spain
- Current address: Hospital Infantil de México “Federico Gómez”, México, D.F., México
| | - Javier Díaz-Nido
- Centro de Biología Molecular Severo Ochoa (UAM-CSIC) and Departamento de Biología Molecular, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Instituto de Investigaciones Sanitarias Hospital Puerta de Hierro-Majadahonda (IDIPHIM), Madrid, Spain
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