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Edzeamey FJ, Ramchunder Z, Pourzand C, Anjomani Virmouni S. Emerging antioxidant therapies in Friedreich's ataxia. Front Pharmacol 2024; 15:1359618. [PMID: 38379897 PMCID: PMC10876797 DOI: 10.3389/fphar.2024.1359618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 01/25/2024] [Indexed: 02/22/2024] Open
Abstract
Friedreich's ataxia (FRDA) is a rare childhood neurologic disorder, affecting 1 in 50,000 Caucasians. The disease is caused by the abnormal expansion of the GAA repeat sequence in intron 1 of the FXN gene, leading to the reduced expression of the mitochondrial protein frataxin. The disease is characterised by progressive neurodegeneration, hypertrophic cardiomyopathy, diabetes mellitus and musculoskeletal deformities. The reduced expression of frataxin has been suggested to result in the downregulation of endogenous antioxidant defence mechanisms and mitochondrial bioenergetics, and the increase in mitochondrial iron accumulation thereby leading to oxidative stress. The confirmation of oxidative stress as one of the pathological signatures of FRDA led to the search for antioxidants which can be used as therapeutic modality. Based on this observation, antioxidants with different mechanisms of action have been explored for FRDA therapy since the last two decades. In this review, we bring forth all antioxidants which have been investigated for FRDA therapy and have been signed off for clinical trials. We summarise their various target points in FRDA disease pathway, their performances during clinical trials and possible factors which might have accounted for their failure or otherwise during clinical trials. We also discuss the limitation of the studies completed and propose possible strategies for combinatorial therapy of antioxidants to generate synergistic effect in FRDA patients.
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Affiliation(s)
- Fred Jonathan Edzeamey
- Ataxia Research Group, Division of Biosciences, Department of Life Sciences, College of Health, Medicine, and Life Sciences (CHMLS), Brunel University London, Uxbridge, United Kingdom
| | - Zenouska Ramchunder
- Ataxia Research Group, Division of Biosciences, Department of Life Sciences, College of Health, Medicine, and Life Sciences (CHMLS), Brunel University London, Uxbridge, United Kingdom
| | - Charareh Pourzand
- Department of Life Sciences, University of Bath, Bath, United Kingdom
- Centre for Therapeutic Innovation, University of Bath, Bath, United Kingdom
| | - Sara Anjomani Virmouni
- Ataxia Research Group, Division of Biosciences, Department of Life Sciences, College of Health, Medicine, and Life Sciences (CHMLS), Brunel University London, Uxbridge, United Kingdom
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Yang YN, Zhang MQ, Yu FL, Han B, Bao MY, Yan-He, Li X, Zhang Y. Peroxisom proliferator-activated receptor-γ coactivator-1α in neurodegenerative disorders: A promising therapeutic target. Biochem Pharmacol 2023; 215:115717. [PMID: 37516277 DOI: 10.1016/j.bcp.2023.115717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Revised: 07/26/2023] [Accepted: 07/26/2023] [Indexed: 07/31/2023]
Abstract
Neurodegenerative disorders (NDDs) are characterized by progressive loss of selectively vulnerable neuronal populations and myelin sheath, leading to behavioral and cognitive dysfunction that adversely affect the quality of life. Identifying novel therapies that attenuate the progression of NDDs would be of significance. Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), a widely expressed transcriptional regulator, modulates the expression of genes engaged in mitochondrial biosynthesis, metabolic regulation, and oxidative stress (OS). Emerging evidences point to the strong connection between PGC-1α and NDDs, suggesting its positive impaction on the progression of NDDs. Therefore, it is urgent to gain a deeper and broader understanding between PGC-1α and NDDs. To this end, this review presents a comprehensive overview of PGC-1α, including its basic characteristics, the post-translational modulations, as well as the interacting transcription factors. Secondly, the pathogenesis of PGC-1α in various NDDs, such as Alzheimer's (AD), Parkinson's (PD), and Huntington's disease (HD) is briefly discussed. Additionally, this study summarizes the underlying mechanisms that PGC-1α is neuroprotective in NDDs via regulating neuroinflammation, OS, and mitochondrial dysfunction. Finally, we briefly outline the shortcomings of current NDDs drug therapy, and summarize the functions and potential applications of currently available PGC-1α modulators (activator or inhibitors). Generally, this review updates our insight of the important role of PGC-1α on the development of NDDs, and provides a promising therapeutic target/ drug for the treatment of NDDs.
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Affiliation(s)
- Ya-Na Yang
- Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry (Shaanxi Normal University), The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Mao-Qing Zhang
- Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry (Shaanxi Normal University), The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Feng-Lin Yu
- Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry (Shaanxi Normal University), The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Bing Han
- Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry (Shaanxi Normal University), The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Ming-Yue Bao
- Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry (Shaanxi Normal University), The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Yan-He
- Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry (Shaanxi Normal University), The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Xing Li
- Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry (Shaanxi Normal University), The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China
| | - Yuan Zhang
- Key Laboratory of Medicinal Resources and Natural Pharmaceutical Chemistry (Shaanxi Normal University), The Ministry of Education, College of Life Sciences, Shaanxi Normal University, Xi'an, Shaanxi 710119, China.
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Abeti R, Jasoliya M, Al-Mahdawi S, Pook M, Gonzalez-Robles C, Hui CK, Cortopassi G, Giunti P. A Drug Combination Rescues Frataxin-Dependent Neural and Cardiac Pathophysiology in FA Models. Front Mol Biosci 2022; 9:830650. [PMID: 35664670 PMCID: PMC9160322 DOI: 10.3389/fmolb.2022.830650] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 03/17/2022] [Indexed: 11/22/2022] Open
Abstract
Friedreich’s ataxia (FA) is an inherited multisystemic neuro- and cardio-degenerative disorder. Seventy-four clinical trials are listed for FA (including past and present), but none are considered FDA/EMA-approved therapy. To date, FA therapeutic strategies have focused along two main lines using a single-drug approach: a) increasing frataxin and b) enhancing downstream pathways, including antioxidant levels and mitochondrial function. Our novel strategy employed a combinatorial approach to screen approved compounds to determine if a combination of molecules provided an additive or synergistic benefit to FA cells and/or animal models. Eight single drug molecules were administered to FA fibroblast patient cells: nicotinamide riboside, hemin, betamethasone, resveratrol, epicatechin, histone deacetylase inhibitor 109, methylene blue, and dimethyl fumarate. We measured their individual ability to induce FXN transcription and mitochondrial biogenesis in patient cells. Single-drug testing highlighted that dimethyl fumarate and resveratrol increased these two parameters. In addition, the simultaneous administration of these two drugs was the most effective in terms of FXN mRNA and mitobiogenesis increase. Interestingly, this combination also improved mitochondrial functions and reduced reactive oxygen species in neurons and cardiomyocytes. Behavioral tests in an FA mouse model treated with dimethyl fumarate and resveratrol demonstrated improved rotarod performance. Our data suggest that dimethyl fumarate is effective as a single agent, and the addition of resveratrol provides further benefit in some assays without showing toxicity. Therefore, they could be a valuable combination to counteract FA pathophysiology. Further studies will help fully understand the potential of a combined therapeutic strategy in FA pathophysiology.
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Affiliation(s)
- Rosella Abeti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL, Institute of Neurology, London, United Kingdom
- *Correspondence: Rosella Abeti, ; Paola Giunti,
| | - Mittal Jasoliya
- Department of Molecular Biosciences, School of Veterinary Medicine, UC Davis, Davis, CA, United States
| | - Sahar Al-Mahdawi
- Department of Life Sciences, Institute of Environment, Health, and Societies, College of Health and Life Sciences, Division of Biosciences, Brunel University London, Uxbridge, United Kingdom
| | - Mark Pook
- Department of Life Sciences, Institute of Environment, Health, and Societies, College of Health and Life Sciences, Division of Biosciences, Brunel University London, Uxbridge, United Kingdom
| | - Cristina Gonzalez-Robles
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL, Institute of Neurology, London, United Kingdom
| | - Chun Kiu Hui
- Department of Molecular Biosciences, School of Veterinary Medicine, UC Davis, Davis, CA, United States
| | - Gino Cortopassi
- Department of Molecular Biosciences, School of Veterinary Medicine, UC Davis, Davis, CA, United States
| | - Paola Giunti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL, Institute of Neurology, London, United Kingdom
- *Correspondence: Rosella Abeti, ; Paola Giunti,
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Personalized Medicine to Improve Treatment of Dopa-Responsive Dystonia-A Focus on Tyrosine Hydroxylase Deficiency. J Pers Med 2021; 11:jpm11111186. [PMID: 34834538 PMCID: PMC8625014 DOI: 10.3390/jpm11111186] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 11/25/2022] Open
Abstract
Dopa-responsive dystonia (DRD) is a rare movement disorder associated with defective dopamine synthesis. This impairment may be due to the fact of a deficiency in GTP cyclohydrolase I (GTPCHI, GCH1 gene), sepiapterin reductase (SR), tyrosine hydroxylase (TH), or 6-pyruvoyl tetrahydrobiopterin synthase (PTPS) enzyme functions. Mutations in GCH1 are most frequent, whereas fewer cases have been reported for individual SR-, PTP synthase-, and TH deficiencies. Although termed DRD, a subset of patients responds poorly to L-DOPA. As this is regularly observed in severe cases of TH deficiency (THD), there is an urgent demand for more adequate or personalized treatment options. TH is a key enzyme that catalyzes the rate-limiting step in catecholamine biosynthesis, and THD patients often present with complex and variable phenotypes, which results in frequent misdiagnosis and lack of appropriate treatment. In this expert opinion review, we focus on THD pathophysiology and ongoing efforts to develop novel therapeutics for this rare disorder. We also describe how different modeling approaches can be used to improve genotype to phenotype predictions and to develop in silico testing of treatment strategies. We further discuss the current status of mathematical modeling of catecholamine synthesis and how such models can be used together with biochemical data to improve treatment of DRD patients.
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Castro IH, Bringas M, Doni D, Noguera ME, Capece L, Aran M, Blaustein M, Costantini P, Santos J. Relationship between activity and stability: Design and characterization of stable variants of human frataxin. Arch Biochem Biophys 2020; 691:108491. [PMID: 32707090 DOI: 10.1016/j.abb.2020.108491] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/26/2020] [Accepted: 07/08/2020] [Indexed: 11/16/2022]
Abstract
The relationships between conformational dynamics, stability and protein function are not obvious. Frataxin (FXN) is an essential protein that forms part of a supercomplex dedicated to the iron-sulfur (Fe-S) cluster assembly within the mitochondrial matrix. In humans, the loss of FXN expression or a decrease in its functionality results in Friedreich's Ataxia, a cardio-neurodegenerative disease. Recently, the way in which FXN interacts with the rest of the subunits of the supercomplex was uncovered. This opens a window to explore relationships between structural dynamics and function. In this study, we prepared a set of FXN variants spanning a broad range of conformational stabilities. Variants S160I, S160M and A204R were more stable than the wild-type and showed similar biological activity. Additionally, we prepared SILCAR, a variant that combines S160I, L203C and A204R mutations. SILCAR was 2.4 kcal mol-1 more stable and equally active. Some of the variants were significantly more resistant to proteolysis than the wild-type FXN. SILCAR showed the highest resistance, suggesting a more rigid structure. It was corroborated by means of molecular dynamics simulations. Relaxation dispersion NMR experiments comparing SILCAR and wild-type variants suggested similar internal motions in the microsecond to millisecond timescale. Instead, variant S157I showed higher denaturation resistance but a significant lower function, similarly to that observed for the FRDA variant N146K. We concluded that the contribution of particular side chains to the conformational stability of FXN might be highly subordinated to their impact on both the protein function and the stability of the functional supercomplex.
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Affiliation(s)
- Ignacio Hugo Castro
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina
| | - Mauro Bringas
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE CONICET), C1428EGA, Buenos Aires, Argentina
| | - Davide Doni
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131, Padova, Italy
| | - Martin Ezequiel Noguera
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina; Instituto de Química y Fisicoquímica Biológicas, Dr. Alejandro Paladini, Universidad de Buenos Aires, CONICET, Junín 956, C1113AAD, Buenos Aires, Argentina
| | - Luciana Capece
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE CONICET), C1428EGA, Buenos Aires, Argentina
| | - Martín Aran
- Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, C1405BWE, Buenos Aires, Argentina
| | - Matías Blaustein
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, C1033AAJ, Buenos Aires, Argentina
| | - Paola Costantini
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131, Padova, Italy
| | - Javier Santos
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, C1033AAJ, Buenos Aires, Argentina; Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina.
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6
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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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Helma R, Bažantová P, Petr M, Adámik M, Renčiuk D, Tichý V, Pastuchová A, Soldánová Z, Pečinka P, Bowater RP, Fojta M, Brázdová M. p53 Binds Preferentially to Non-B DNA Structures Formed by the Pyrimidine-Rich Strands of GAA·TTC Trinucleotide Repeats Associated with Friedreich's Ataxia. Molecules 2019; 24:molecules24112078. [PMID: 31159174 PMCID: PMC6600395 DOI: 10.3390/molecules24112078] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/19/2019] [Accepted: 05/30/2019] [Indexed: 01/12/2023] Open
Abstract
Expansions of trinucleotide repeats (TNRs) are associated with genetic disorders such as Friedreich's ataxia. The tumor suppressor p53 is a central regulator of cell fate in response to different types of insults. Sequence and structure-selective modes of DNA recognition are among the main attributes of p53 protein. The focus of this work was analysis of the p53 structure-selective recognition of TNRs associated with human neurodegenerative diseases. Here, we studied binding of full length p53 and several deletion variants to TNRs folded into DNA hairpins or loops. We demonstrate that p53 binds to all studied non-B DNA structures, with a preference for non-B DNA structures formed by pyrimidine (Py) rich strands. Using deletion mutants, we determined the C-terminal DNA binding domain of p53 to be crucial for recognition of such non-B DNA structures. We also observed that p53 in vitro prefers binding to the Py-rich strand over the purine (Pu) rich strand in non-B DNA substrates formed by sequence derived from the first intron of the frataxin gene. The binding of p53 to this region was confirmed using chromatin immunoprecipitation in human Friedreich's ataxia fibroblast and adenocarcinoma cells. Altogether these observations provide further evidence that p53 binds to TNRs' non-B DNA structures.
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Affiliation(s)
- Robert Helma
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
- Department of Molecular Biology and Pharmaceutical Biotechnology, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 612 42 Brno, Czech Republic.
| | - Pavla Bažantová
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
- Faculty of Science, University of Ostrava, Chittussiho 10, 701 03 Ostrava, Czech Republic.
| | - Marek Petr
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
- Department of Molecular Biology and Pharmaceutical Biotechnology, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 612 42 Brno, Czech Republic.
| | - Matej Adámik
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
| | - Daniel Renčiuk
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
| | - Vlastimil Tichý
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
| | - Alena Pastuchová
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
| | - Zuzana Soldánová
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
- Department of Molecular Biology and Pharmaceutical Biotechnology, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 612 42 Brno, Czech Republic.
| | - Petr Pečinka
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
- Faculty of Science, University of Ostrava, Chittussiho 10, 701 03 Ostrava, Czech Republic.
| | - Richard P Bowater
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
| | - Miroslav Fojta
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, CZ-62500 Brno, Czech Republic.
| | - Marie Brázdová
- Institute of Biophysics, Academy of Sciences of the Czech Republic v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
- Department of Molecular Biology and Pharmaceutical Biotechnology, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences Brno, Palackého 1/3, 612 42 Brno, Czech Republic.
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8
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Rose SJ, Hess EJ. A commentary on the utility of a new L-DOPA-responsive dystonia mouse model. Rare Dis 2015; 4:e1128617. [PMID: 27141408 PMCID: PMC4838313 DOI: 10.1080/21675511.2015.1128617] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 11/11/2015] [Accepted: 12/01/2015] [Indexed: 11/26/2022] Open
Abstract
In a recent issue of Brain, we reported on the generation and characterization of a mouse model of the rare disease L-DOPA-responsive dystonia (DRD). Here, we discuss the utility of these mice for understanding broader disease processes and treatment strategies. Using specific experimental designs that either work “forward” from genetic etiology or “backward” from the symptomatic presentation, we discuss how our data and future work can be used to understand broader themes.
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Affiliation(s)
- Samuel J Rose
- Department of Pharmacology, Emory University School of Medicine , Atlanta, GA, USA
| | - Ellen J Hess
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
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9
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GAA triplet-repeats cause nucleosome depletion in the human genome. Genomics 2015; 106:88-95. [DOI: 10.1016/j.ygeno.2015.06.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Revised: 06/15/2015] [Accepted: 06/18/2015] [Indexed: 11/18/2022]
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Abstract
OPINION STATEMENT Ataxia can originate from many genetic defects, but also from nongenetic causes. To be able to provide treatment, the first step is to establish the right diagnosis. Once the cause of the ataxia is defined, some specific treatments may be available. For example, the nongenetic ataxias that arise from vitamin deficiencies can improve following treatment. In most cases, however, therapies do not cure the disease and are purely symptomatic. Physiotherapy and occupational therapy are effective in all type of ataxias and often remain the most efficient treatment option for these patients to maximize their quality of life.
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Triple Therapy with Darbepoetin Alfa, Idebenone, and Riboflavin in Friedreich’s Ataxia: an Open-Label Trial. THE CEREBELLUM 2013; 12:713-20. [DOI: 10.1007/s12311-013-0482-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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12
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Beconi M, Aziz O, Matthews K, Moumné L, O’Connell C, Yates D, Clifton S, Pett H, Vann J, Crowley L, Haughan AF, Smith DL, Woodman B, Bates GP, Brookfield F, Bürli RW, McAllister G, Dominguez C, Munoz-Sanjuan I, Beaumont V. Oral administration of the pimelic diphenylamide HDAC inhibitor HDACi 4b is unsuitable for chronic inhibition of HDAC activity in the CNS in vivo. PLoS One 2012; 7:e44498. [PMID: 22973455 PMCID: PMC3433414 DOI: 10.1371/journal.pone.0044498] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 08/07/2012] [Indexed: 11/24/2022] Open
Abstract
Histone deacetylase (HDAC) inhibitors have received considerable attention as potential therapeutics for a variety of cancers and neurological disorders. Recent publications on a class of pimelic diphenylamide HDAC inhibitors have highlighted their promise in the treatment of the neurodegenerative diseases Friedreich’s ataxia and Huntington’s disease, based on efficacy in cell and mouse models. These studies’ authors have proposed that the unique action of these compounds compared to hydroxamic acid-based HDAC inhibitors results from their unusual slow-on/slow-off kinetics of binding, preferentially to HDAC3, resulting in a distinctive pharmacological profile and reduced toxicity. Here, we evaluate the HDAC subtype selectivity, cellular activity, absorption, distribution, metabolism and excretion (ADME) properties, as well as the central pharmacodynamic profile of one such compound, HDACi 4b, previously described to show efficacy in vivo in the R6/2 mouse model of Huntington’s disease. Based on our data reported here, we conclude that while the in vitro selectivity and binding mode are largely in agreement with previous reports, the physicochemical properties, metabolic and p-glycoprotein (Pgp) substrate liability of HDACi 4b render this compound suboptimal to investigate central Class I HDAC inhibition in vivo in mouse per oral administration. A drug administration regimen using HDACi 4b dissolved in drinking water was used in the previous proof of concept study, casting doubt on the validation of CNS HDAC3 inhibition as a target for the treatment of Huntington’s disease. We highlight physicochemical stability and metabolic issues with 4b that are likely intrinsic liabilities of the benzamide chemotype in general.
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Affiliation(s)
- Maria Beconi
- CHDI Management/CHDI Foundation Inc., Los Angeles, California, United States of America
| | - Omar Aziz
- BioFocus, Saffron Walden, Essex, United Kingdom
| | | | - Lara Moumné
- Department of Medical and Molecular Genetics, King's College London, London, United Kingdom
| | | | - Dawn Yates
- BioFocus, Saffron Walden, Essex, United Kingdom
| | | | - Hannah Pett
- BioFocus, Saffron Walden, Essex, United Kingdom
| | - Julie Vann
- BioFocus, Saffron Walden, Essex, United Kingdom
| | | | | | - Donna L. Smith
- Department of Medical and Molecular Genetics, King's College London, London, United Kingdom
| | - Ben Woodman
- Department of Medical and Molecular Genetics, King's College London, London, United Kingdom
| | - Gillian P. Bates
- Department of Medical and Molecular Genetics, King's College London, London, United Kingdom
| | | | | | | | - Celia Dominguez
- CHDI Management/CHDI Foundation Inc., Los Angeles, California, United States of America
| | - Ignacio Munoz-Sanjuan
- CHDI Management/CHDI Foundation Inc., Los Angeles, California, United States of America
| | - Vahri Beaumont
- CHDI Management/CHDI Foundation Inc., Los Angeles, California, United States of America
- * E-mail:
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13
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Kemp K, Mallam E, Hares K, Witherick J, Scolding N, Wilkins A. Mesenchymal stem cells restore frataxin expression and increase hydrogen peroxide scavenging enzymes in Friedreich ataxia fibroblasts. PLoS One 2011; 6:e26098. [PMID: 22016819 PMCID: PMC3189234 DOI: 10.1371/journal.pone.0026098] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 09/19/2011] [Indexed: 01/01/2023] Open
Abstract
Dramatic advances in recent decades in understanding the genetics of Friedreich ataxia (FRDA)--a GAA triplet expansion causing greatly reduced expression of the mitochondrial protein frataxin--have thus far yielded no therapeutic dividend, since there remain no effective treatments that prevent or even slow the inevitable progressive disability in affected individuals. Clinical interventions that restore frataxin expression are attractive therapeutic approaches, as, in theory, it may be possible to re-establish normal function in frataxin deficient cells if frataxin levels are increased above a specific threshold. With this in mind several drugs and cytokines have been tested for their ability to increase frataxin levels. Cell transplantation strategies may provide an alternative approach to this therapeutic aim, and may also offer more widespread cellular protective roles in FRDA. Here we show a direct link between frataxin expression in fibroblasts derived from FRDA patients with both decreased expression of hydrogen peroxide scavenging enzymes and increased sensitivity to hydrogen peroxide-mediated toxicity. We demonstrate that normal human mesenchymal stem cells (MSCs) induce both an increase in frataxin gene and protein expression in FRDA fibroblasts via secretion of soluble factors. Finally, we show that exposure to factors produced by human MSCs increases resistance to hydrogen peroxide-mediated toxicity in FRDA fibroblasts through, at least in part, restoring the expression of the hydrogen peroxide scavenging enzymes catalase and glutathione peroxidase 1. These findings suggest, for the first time, that stem cells may increase frataxin levels in FRDA and transplantation of MSCs may offer an effective treatment for these patients.
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Affiliation(s)
- Kevin Kemp
- Multiple Sclerosis and Stem Cell Group, Institute of Clinical Neurosciences, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom.
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14
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Abstract
The brain is rich in metals and has a high metabolic rate, making it acutely vulnerable to the toxic effects of endogenously produced free radicals. The abundant metals, iron and copper, transfer single electrons as they cycle between their reduced (Fe(2+) , Cu(1+) ) and oxidized (Fe(3+) , Cu(2+) ) states making them powerful catalysts of reactive oxygen species (ROS) production. Even redox inert zinc, if present in excess, can trigger ROS production indirectly by altering mitochondrial function. While metal chelators seem to improve the clinical outcome of several neurodegenerative diseases, their mechanisms of action remain obscure and the effects of long-term use are largely unknown. Most chelators are not specific to a single metal and could alter the distribution of multiple metals in the brain, leading to unexpected consequences over the long-term. We show here how X-ray fluorescence will be a valuable tool to examine the effect of chelators on the distribution and amount of metals in the brain.
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Affiliation(s)
| | - Helen Nichol
- Department of Anatomy and Cell Biology, University of Saskatchewan, Saskatoon, Canada
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15
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Rufini A, Fortuni S, Arcuri G, Condò I, Serio D, Incani O, Malisan F, Ventura N, Testi R. Preventing the ubiquitin-proteasome-dependent degradation of frataxin, the protein defective in Friedreich's ataxia. Hum Mol Genet 2011; 20:1253-61. [PMID: 21216878 DOI: 10.1093/hmg/ddq566] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Friedreich's ataxia (FRDA) is a devastating orphan disease, with no specific treatment. The disease is caused by reduced expression of the protein frataxin, which results in mitochondrial defects and oxidative damage. Levels of residual frataxin critically affect onset and progression of the disease. Understanding the molecular mechanisms that regulate frataxin stability and degradation may, therefore, be exploited for the design of effective therapeutics. Here we show that frataxin is degraded by the ubiquitin-proteasome system and that K(147) is the critical residue responsible for frataxin ubiquitination and degradation. Accordingly, a K(147)R substitution generates a more stable frataxin. We then disclose a set of lead compounds, computationally selected to target the molecular cleft harboring K(147), that can prevent frataxin ubiquitination and degradation, and increase frataxin levels in cells derived from FRDA patients. Moreover, treatment with these compounds induces substantial recovery of aconitase activity and adenosine-5'-triphosphate levels in FRDA cells. Thus, we provide evidence for the therapeutic potential of directly interfering with the frataxin degradation pathway.
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Affiliation(s)
- Alessandra Rufini
- Laboratory of Signal Transduction, Department of Experimental Medicine, University of Rome Tor Vergata, Via Montpellier 1, 00133 Rome, Italy
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16
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Morton SM, Tseng YW, Zackowski KM, Daline JR, Bastian AJ. Longitudinal tracking of gait and balance impairments in cerebellar disease. Mov Disord 2010; 25:1944-52. [PMID: 20544808 DOI: 10.1002/mds.23169] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Cerebellar damage typically results in ataxia and can be caused by stroke, tumor, or one of many forms of degenerative disease. Since few pharmacological options are available, most treatments rely heavily on rehabilitation therapy. Little data exist on methods for tracking the progression of ataxia, which is critical for assessing the efficacy of current and newly developing treatments. Here, we tracked the severity of ataxia, with a particular emphasis on gait and balance dysfunction, in a group of individuals with cerebellar damage using the International Cooperative Ataxia Rating Scale (ICARS) and several instrumented laboratory measures of gait and balance impairments over 1 year. We found that the ICARS was able to distinguish between subjects with static lesions and those with degenerative disorders, was sensitive to increases in ataxia severity occurring over 1 year, and correlated well with specific instrumented measures of gait in persons with cerebellar degeneration. These results suggest the ICARS is a valuable tool for clinicians and investigators to document and track long-term changes in gait and balance performance in individuals with cerebellar degenerative disorders.
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Affiliation(s)
- Susanne M Morton
- Graduate Program in Physical Therapy and Rehabilitation Science, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
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17
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Herrero AJ, Martín J, Martín T, García-López D, Garatachea N, Jiménez B, Marín PJ. Whole-body vibration alters blood flow velocity and neuromuscular activity in Friedreich's ataxia. Clin Physiol Funct Imaging 2010; 31:139-44. [PMID: 21078065 DOI: 10.1111/j.1475-097x.2010.00992.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The purpose of this study was to investigate the effects of whole-body vibration (WBV) on blood flow velocity and muscular activity after different vibration protocols in Friedreich's ataxia (FA) patients. After two familiarization sessions ten patients received six 3 min WBV treatments depending on a combination of frequency (10, 20 or 30 Hz) and protocol (constant or fragmented). Femoral artery blood flow velocity, vastus lateralis (VL) and vastus medialis (VM) electromyography (EMG), and rate of perceived exertion were registered. Peak blood velocity was increased with respect to basal values after 1, 2 and 3 min of WBV (14·8%, 18·8% and 19·7%, respectively, P<0·001). Likewise, mean blood velocity was increased with respect to basal values after 1, 2 and 3 min of WBV (17·3%, 19·4% and 16·6%, respectively, P<0·001). EMG amplitude of VL and VM was increased (39% and 23%, respectively, P<0·05) and EMG frequencies decreased during the application of WBV. The results of this study suggest that higher frequencies (30 Hz) produce a greater increase in blood flow velocity and rate of perceived exertion. WBV is an effective method to increase blood flow and to activate muscle mass in patients with Friedreich's ataxia, and could therefore be considered to be incorporated in rehabilitation programs of this collective.
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Affiliation(s)
- Azael J Herrero
- Research Center on Physical Disability, ASPAYM Castilla y León, Valladolid, Spain.
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18
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Kell DB. Towards a unifying, systems biology understanding of large-scale cellular death and destruction caused by poorly liganded iron: Parkinson's, Huntington's, Alzheimer's, prions, bactericides, chemical toxicology and others as examples. Arch Toxicol 2010; 84:825-89. [PMID: 20967426 PMCID: PMC2988997 DOI: 10.1007/s00204-010-0577-x] [Citation(s) in RCA: 286] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Accepted: 07/14/2010] [Indexed: 12/11/2022]
Abstract
Exposure to a variety of toxins and/or infectious agents leads to disease, degeneration and death, often characterised by circumstances in which cells or tissues do not merely die and cease to function but may be more or less entirely obliterated. It is then legitimate to ask the question as to whether, despite the many kinds of agent involved, there may be at least some unifying mechanisms of such cell death and destruction. I summarise the evidence that in a great many cases, one underlying mechanism, providing major stresses of this type, entails continuing and autocatalytic production (based on positive feedback mechanisms) of hydroxyl radicals via Fenton chemistry involving poorly liganded iron, leading to cell death via apoptosis (probably including via pathways induced by changes in the NF-κB system). While every pathway is in some sense connected to every other one, I highlight the literature evidence suggesting that the degenerative effects of many diseases and toxicological insults converge on iron dysregulation. This highlights specifically the role of iron metabolism, and the detailed speciation of iron, in chemical and other toxicology, and has significant implications for the use of iron chelating substances (probably in partnership with appropriate anti-oxidants) as nutritional or therapeutic agents in inhibiting both the progression of these mainly degenerative diseases and the sequelae of both chronic and acute toxin exposure. The complexity of biochemical networks, especially those involving autocatalytic behaviour and positive feedbacks, means that multiple interventions (e.g. of iron chelators plus antioxidants) are likely to prove most effective. A variety of systems biology approaches, that I summarise, can predict both the mechanisms involved in these cell death pathways and the optimal sites of action for nutritional or pharmacological interventions.
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Affiliation(s)
- Douglas B Kell
- School of Chemistry and the Manchester Interdisciplinary Biocentre, The University of Manchester, Manchester M1 7DN, UK.
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19
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Abstract
The transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC-1alpha) is a master regulator of metabolism in peripheral tissues, and it has been proposed that PGC-1alpha plays a similar role in the brain. Recent evidence suggests that PGC-1alpha is concentrated in GABAergic interneurons, so we investigated whether male and female PGC-1alpha -/- mice exhibit abnormalities in interneuron gene expression and/or function. We found a striking reduction in the expression of the Ca(2+)-binding protein parvalbumin (PV), but not other GABAergic markers, throughout the cerebrum in PGC-1alpha +/- and -/- mice. Furthermore, PGC-1alpha overexpression in cell culture was sufficient to robustly induce PV expression. Consistent with a reduction in PV rather than a loss of PV-expressing interneurons, spontaneous synaptic inhibition was not altered in PGC-1alpha -/- mice. However, evoked synaptic responses displayed less paired-pulse depression and dramatic facilitation in response to repetitive stimulation at the gamma frequency. PV transcript expression was also significantly reduced in retina and heart of PGC-1alpha -/- animals, suggesting that PGC-1alpha is required for proper expression of PV in multiple tissues. Together these findings indicate that PGC-1alpha is a novel regulator of interneuron gene expression and function and a potential therapeutic target for neurological disorders associated with interneuron dysfunction.
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20
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Revuelta GJ, Wilmot GR. Therapeutic Interventions in the Primary Hereditary Ataxias. Curr Treat Options Neurol 2010; 12:257-73. [DOI: 10.1007/s11940-010-0075-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Marmolino D, Manto M, Acquaviva F, Vergara P, Ravella A, Monticelli A, Pandolfo M. PGC-1alpha down-regulation affects the antioxidant response in Friedreich's ataxia. PLoS One 2010; 5:e10025. [PMID: 20383327 PMCID: PMC2850922 DOI: 10.1371/journal.pone.0010025] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2010] [Accepted: 03/16/2010] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Cells from individuals with Friedreich's ataxia (FRDA) show reduced activities of antioxidant enzymes and cannot up-regulate their expression when exposed to oxidative stress. This blunted antioxidant response may play a central role in the pathogenesis. We previously reported that Peroxisome Proliferator Activated Receptor Gamma (PPARgamma) Coactivator 1-alpha (PGC-1alpha), a transcriptional master regulator of mitochondrial biogenesis and antioxidant responses, is down-regulated in most cell types from FRDA patients and animal models. METHODOLOGY/PRINCIPAL FINDINGS We used primary fibroblasts from FRDA patients and the knock in-knock out animal model for the disease (KIKO mouse) to determine basal superoxide dismutase 2 (SOD2) levels and the response to oxidative stress induced by the addition of hydrogen peroxide. We measured the same parameters after pharmacological stimulation of PGC-1alpha. Compared to control cells, PGC-1alpha and SOD2 levels were decreased in FRDA cells and did not change after addition of hydrogen peroxide. PGC-1alpha direct silencing with siRNA in control fibroblasts led to a similar loss of SOD2 response to oxidative stress as observed in FRDA fibroblasts. PGC-1alpha activation with the PPARgamma agonist (Pioglitazone) or with a cAMP-dependent protein kinase (AMPK) agonist (AICAR) restored normal SOD2 induction. Treatment of the KIKO mice with Pioglitazone significantly up-regulates SOD2 in cerebellum and spinal cord. CONCLUSIONS/SIGNIFICANCE PGC-1alpha down-regulation is likely to contribute to the blunted antioxidant response observed in cells from FRDA patients. This response can be restored by AMPK and PPARgamma agonists, suggesting a potential therapeutic approach for FRDA.
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Affiliation(s)
- Daniele Marmolino
- Laboratoire de Neurologie Expérimentale, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | - Mario Manto
- Laboratoire de Neurologie Expérimentale, Université Libre de Bruxelles (ULB), Brussels, Belgium
- Fonds National de la Recherche Scientifique (FNRS), Brussels, Belgium
| | - Fabio Acquaviva
- Department of Cellular and Molecular Biology, University of Naples “Federico II”, Naples, Italy
| | - Paola Vergara
- Department of Cellular and Molecular Biology, University of Naples “Federico II”, Naples, Italy
| | - Ajay Ravella
- Laboratoire de Neurologie Expérimentale, Université Libre de Bruxelles (ULB), Brussels, Belgium
| | | | - Massimo Pandolfo
- Laboratoire de Neurologie Expérimentale, Université Libre de Bruxelles (ULB), Brussels, Belgium
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22
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A new myohaptic instrument to assess wrist motion dynamically. SENSORS 2010; 10:3180-94. [PMID: 22319293 PMCID: PMC3274218 DOI: 10.3390/s100403180] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 02/11/2010] [Accepted: 03/24/2010] [Indexed: 11/29/2022]
Abstract
The pathophysiological assessment of joint properties and voluntary motion in neurological patients remains a challenge. This is typically the case in cerebellar patients, who exhibit dysmetric movements due to the dysfunction of cerebellar circuitry. Several tools have been developed, but so far most of these tools have remained confined to laboratories, with a lack of standardization. We report on a new device which combines the use of electromyographic (EMG) sensors with haptic technology for the dynamic investigation of wrist properties. The instrument is composed of a drivetrain, a haptic controller and a signal acquisition unit. Angular accuracy is 0.00611 rad, nominal torque is 6 N·m, maximal rotation velocity is 34.907 rad/sec, with a range of motion of −1.0472 to +1.0472 rad. The inertia of the motor and handgrip is 0.004 kg·m2. This is the first standardized myohaptic instrument allowing the dynamic characterization of wrist properties, including under the condition of artificial damping. We show that cerebellar patients are unable to adapt EMG activities when faced with an increase in damping while performing fast reversal movements. The instrument allows the extraction of an electrophysiological signature of a cerebellar deficit.
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Marmolino D, Manto M. Past, present and future therapeutics for cerebellar ataxias. Curr Neuropharmacol 2010; 8:41-61. [PMID: 20808545 PMCID: PMC2866461 DOI: 10.2174/157015910790909476] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 11/18/2009] [Accepted: 11/30/2009] [Indexed: 01/14/2023] Open
Abstract
Cerebellar ataxias are a group of disabling neurological disorders. Patients exhibit a cerebellar syndrome and can also present with extra-cerebellar deficits, namely pigmentary retinopathy, extrapyramidal movement disorders, pyramidal signs, cortical symptoms (seizures, cognitive impairment/behavioural symptoms), and peripheral neuropathy. Recently, deficits in cognitive operations have been unraveled. Cerebellar ataxias are heterogeneous both at the phenotypic and genotypic point of view. Therapeutical trials performed during these last 4 decades have failed in most cases, in particular because drugs were not targeting a deleterious pathway, but were given to counteract putative defects in neurotransmission. The identification of the causative mutations of many hereditary ataxias, the development of relevant animal models and the recent identifications of the molecular mechanisms underlying ataxias are impacting on the development of new drugs. We provide an overview of the pharmacological treatments currently used in the clinical practice and we discuss the drugs under development.
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Affiliation(s)
- D Marmolino
- Laboratoire de Neurologie Expèrimentale ULB-Erasme, Brussels, Belgium.
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