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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Frison M, Faccenda D, Abeti R, Rigon M, Strobbe D, England-Rendon BS, Cash D, Barnes K, Sadeghian M, Sajic M, Wells LA, Xia D, Giunti P, Smith K, Mortiboys H, Turkheimer FE, Campanella M. The translocator protein (TSPO) is prodromal to mitophagy loss in neurotoxicity. Mol Psychiatry 2021; 26:2721-2739. [PMID: 33664474 PMCID: PMC8505241 DOI: 10.1038/s41380-021-01050-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 01/13/2021] [Accepted: 02/05/2021] [Indexed: 12/14/2022]
Abstract
Dysfunctional mitochondria characterise Parkinson's Disease (PD). Uncovering etiological molecules, which harm the homeostasis of mitochondria in response to pathological cues, is therefore pivotal to inform early diagnosis and therapy in the condition, especially in its idiopathic forms. This study proposes the 18 kDa Translocator Protein (TSPO) to be one of those. Both in vitro and in vivo data show that neurotoxins, which phenotypically mimic PD, increase TSPO to enhance cellular redox-stress, susceptibility to dopamine-induced cell death, and repression of ubiquitin-dependent mitophagy. TSPO amplifies the extracellular signal-regulated protein kinase 1 and 2 (ERK1/2) signalling, forming positive feedback, which represses the transcription factor EB (TFEB) and the controlled production of lysosomes. Finally, genetic variances in the transcriptome confirm that TSPO is required to alter the autophagy-lysosomal pathway during neurotoxicity.
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Affiliation(s)
- Michele Frison
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom
- MRC Mitochondrial Biology Unit, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Danilo Faccenda
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom
| | - Rosella Abeti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Queen Square London, United Kingdom
| | - Manuel Rigon
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom
- Department of Biology, University of Rome TorVergata, Via della Ricerca Scientifica, Rome, Italy
| | - Daniela Strobbe
- Department of Biology, University of Rome TorVergata, Via della Ricerca Scientifica, Rome, Italy
| | - Britannie S England-Rendon
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, King's College London, Camberwell, United Kingdom
| | - Katy Barnes
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, United Kingdom
| | - Mona Sadeghian
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Marija Sajic
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Lisa A Wells
- Imanova Limited, Centre for Imaging Sciences, Imperial College London, Hammersmith Hospital, London, United Kingdom
| | - Dong Xia
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom
| | - Paola Giunti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Queen Square London, United Kingdom
| | - Kenneth Smith
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Heather Mortiboys
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, United Kingdom
| | - Federico E Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, King's College London, Camberwell, United Kingdom
| | - Michelangelo Campanella
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London, United Kingdom.
- Department of Biology, University of Rome TorVergata, Via della Ricerca Scientifica, Rome, Italy.
- University College London Consortium for Mitochondrial Research, London, United Kingdom.
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3
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Strobbe D, Pecorari R, Conte O, Minutolo A, Hendriks CMM, Wiezorek S, Faccenda D, Abeti R, Montesano C, Bolm C, Campanella M. NH-sulfoximine: A novel pharmacological inhibitor of the mitochondrial F 1 F o -ATPase, which suppresses viability of cancerous cells. Br J Pharmacol 2020; 178:298-311. [PMID: 33037618 PMCID: PMC9328437 DOI: 10.1111/bph.15279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 08/27/2020] [Accepted: 09/02/2020] [Indexed: 12/15/2022] Open
Abstract
Background and Purpose The mitochondrial F1Fo‐ATPsynthase is pivotal for cellular homeostasis. When respiration is perturbed, its mode of action everts becoming an F1Fo‐ATPase and therefore consuming rather producing ATP. Such a reversion is an obvious target for pharmacological intervention to counteract pathologies. Despite this, tools to selectively inhibit the phases of ATP hydrolysis without affecting the production of ATP remain scarce. Here, we report on a newly synthesised chemical, the NH‐sulfoximine (NHS), which achieves such a selectivity. Experimental Approach The chemical structure of the F1Fo‐ATPase inhibitor BTB‐06584 was used as a template to synthesise NHS. We assessed its pharmacology in human neuroblastoma SH‐SY5Y cells in which we profiled ATP levels, redox signalling, autophagy pathways and cellular viability. NHS was given alone or in combination with either the glucose analogue 2‐deoxyglucose (2‐DG) or the chemotherapeutic agent etoposide. Key Results NHS selectively blocks the consumption of ATP by mitochondria leading a subtle cytotoxicity associated via the concomitant engagement of autophagy which impairs cell viability. NHS achieves such a function independently of the F1Fo‐ATPase inhibitory factor 1 (IF1). Conclusion and Implications The novel sulfoximine analogue of BTB‐06584, NHS, acts as a selective pharmacological inhibitor of the mitochondrial F1Fo‐ATPase. NHS, by blocking the hydrolysis of ATP perturbs the bioenergetic homoeostasis of cancer cells, leading to a non‐apoptotic type of cell death.
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Affiliation(s)
- Daniela Strobbe
- Department of Biology, University of Rome "Tor Vergata", Rome, Italy
| | - Rosalba Pecorari
- Department of Biology, University of Rome "Tor Vergata", Rome, Italy
| | - Oriana Conte
- Department of Biology, University of Rome "Tor Vergata", Rome, Italy
| | - Antonella Minutolo
- Department of Cell and Developmental Biology, Consortium for Mitochondrial Research (CfMR), University College London, London, UK
| | | | - Stefan Wiezorek
- Institute of Organic Chemistry, RWTH Aachen University, Aachen, Germany
| | - Danilo Faccenda
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, London, UK
| | - Rosella Abeti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Queen Square London, London, WC1N 3BG, UK
| | - Carla Montesano
- Department of Biology, University of Rome "Tor Vergata", Rome, Italy
| | - Carsten Bolm
- Institute of Organic Chemistry, RWTH Aachen University, Aachen, Germany
| | - Michelangelo Campanella
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, London, UK.,Department of Cell and Developmental Biology, Consortium for Mitochondrial Research (CfMR), University College London, London, UK.,Department of Biology, University of Rome "Tor Vergata", Rome, Italy
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Desai R, East DA, Hardy L, Faccenda D, Rigon M, Crosby J, Alvarez MS, Singh A, Mainenti M, Hussey LK, Bentham R, Szabadkai G, Zappulli V, Dhoot GK, Romano LE, Xia D, Coppens I, Hamacher-Brady A, Chapple JP, Abeti R, Fleck RA, Vizcay-Barrena G, Smith K, Campanella M. Mitochondria form contact sites with the nucleus to couple prosurvival retrograde response. Sci Adv 2020; 6:6/51/eabc9955. [PMID: 33355129 DOI: 10.1126/sciadv.abc9955] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 11/13/2020] [Indexed: 05/25/2023]
Abstract
Mitochondria drive cellular adaptation to stress by retro-communicating with the nucleus. This process is known as mitochondrial retrograde response (MRR) and is induced by mitochondrial dysfunction. MRR results in the nuclear stabilization of prosurvival transcription factors such as the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). Here, we demonstrate that MRR is facilitated by contact sites between mitochondria and the nucleus. The translocator protein (TSPO) by preventing the mitophagy-mediated segregation o mitochonria is required for this interaction. The complex formed by TSPO with the protein kinase A (PKA), via the A-kinase anchoring protein acyl-CoA binding domain containing 3 (ACBD3), established the tethering. The latter allows for cholesterol redistribution of cholesterol in the nucleus to sustain the prosurvival response by blocking NF-κB deacetylation. This work proposes a previously unidentified paradigm in MRR: the formation of contact sites between mitochondria and nucleus to aid communication.
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Affiliation(s)
- Radha Desai
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - Daniel A East
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - Liana Hardy
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - Danilo Faccenda
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - Manuel Rigon
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - James Crosby
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - María Soledad Alvarez
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - Aarti Singh
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - Marta Mainenti
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - Laura Kuhlman Hussey
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - Robert Bentham
- Department of Cell and Developmental Biology, Consortium for Mitochondrial Research (CfMR), University College London, Gower Street, London WC1E 6BT, UK
| | - Gyorgy Szabadkai
- Department of Cell and Developmental Biology, Consortium for Mitochondrial Research (CfMR), University College London, Gower Street, London WC1E 6BT, UK
- Department of Biomedical Science, University of Padua, Via Ugo Bassi, 35131 Padua, Italy
- Francis Crick Institute, Midland Road, London NW1 AT, UK
| | - Valentina Zappulli
- Department of Comparative Biomedicine and Food Sciences, University of Padua, Viale dell'Universita' 16, 35020 Legnaro (PD), Italy
| | - Gurtej K Dhoot
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - Lisa E Romano
- William Harvey Research Institute, Barts and the London School of Medicine, Queen Mary University of London, London EC1M 6BQ, UK
| | - Dong Xia
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK
| | - Isabelle Coppens
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Baltimore, Baltimore, MD 21205, USA
| | - Anne Hamacher-Brady
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Baltimore, Baltimore, MD 21205, USA
| | - J Paul Chapple
- William Harvey Research Institute, Barts and the London School of Medicine, Queen Mary University of London, London EC1M 6BQ, UK
| | - Rosella Abeti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Roland A Fleck
- Centre for Ultrastructural Imaging, King's College London, London SE1 1UL, UK
| | - Gema Vizcay-Barrena
- Centre for Ultrastructural Imaging, King's College London, London SE1 1UL, UK
| | - Kenneth Smith
- Pathobiology and Population Sciences, The Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK
| | - Michelangelo Campanella
- Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Royal College Street, London NW1 0TU, UK.
- Department of Cell and Developmental Biology, Consortium for Mitochondrial Research (CfMR), University College London, Gower Street, London WC1E 6BT, UK
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Schottlaender LV, Abeti R, Jaunmuktane Z, Macmillan C, Chelban V, O’Callaghan B, McKinley J, Maroofian R, Efthymiou S, Athanasiou-Fragkouli A, Forbes R, Soutar MP, Livingston JH, Kalmar B, Swayne O, Hotton G, Pittman A, Mendes de Oliveira JR, de Grandis M, Richard-Loendt A, Launchbury F, Althonayan J, McDonnell G, Carr A, Khan S, Beetz C, Bisgin A, Tug Bozdogan S, Begtrup A, Torti E, Greensmith L, Giunti P, Morrison PJ, Brandner S, Aurrand-Lions M, Houlden H, Groppa S, Karashova BM, Nachbauer W, Boesch S, Arning L, Timmann D, Cormand B, Pérez-Dueñas B, Di Rosa G, Goraya JS, Sultan T, Mine J, Avdjieva D, Kathom H, Tincheva R, Banu S, Pineda-Marfa M, Veggiotti P, Ferrari MD, Verrotti A, Marseglia G, Savasta S, García-Silva M, Ruiz AM, Garavaglia B, Borgione E, Portaro S, Sanchez BM, Boles R, Papacostas S, Vikelis M, Papanicolaou EZ, Dardiotis E, Maqbool S, Ibrahim S, Kirmani S, Rana NN, Atawneh O, Koutsis G, Breza M, Mangano S, Scuderi C, Borgione E, Morello G, Stojkovic T, Zollo M, Heimer G, Dauvilliers YA, Striano P, Al-Khawaja I, Al-Mutairi F, Sherifa H. Bi-allelic JAM2 Variants Lead to Early-Onset Recessive Primary Familial Brain Calcification. Am J Hum Genet 2020; 106:412-421. [PMID: 32142645 PMCID: PMC7058839 DOI: 10.1016/j.ajhg.2020.02.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 02/10/2020] [Indexed: 01/30/2023] Open
Abstract
Primary familial brain calcification (PFBC) is a rare neurodegenerative disorder characterized by a combination of neurological, psychiatric, and cognitive decline associated with calcium deposition on brain imaging. To date, mutations in five genes have been linked to PFBC. However, more than 50% of individuals affected by PFBC have no molecular diagnosis. We report four unrelated families presenting with initial learning difficulties and seizures and later psychiatric symptoms, cerebellar ataxia, extrapyramidal signs, and extensive calcifications on brain imaging. Through a combination of homozygosity mapping and exome sequencing, we mapped this phenotype to chromosome 21q21.3 and identified bi-allelic variants in JAM2. JAM2 encodes for the junctional-adhesion-molecule-2, a key tight-junction protein in blood-brain-barrier permeability. We show that JAM2 variants lead to reduction of JAM2 mRNA expression and absence of JAM2 protein in patient’s fibroblasts, consistent with a loss-of-function mechanism. We show that the human phenotype is replicated in the jam2 complete knockout mouse (jam2 KO). Furthermore, neuropathology of jam2 KO mouse showed prominent vacuolation in the cerebral cortex, thalamus, and cerebellum and particularly widespread vacuolation in the midbrain with reactive astrogliosis and neuronal density reduction. The regions of the human brain affected on neuroimaging are similar to the affected brain areas in the myorg PFBC null mouse. Along with JAM3 and OCLN, JAM2 is the third tight-junction gene in which bi-allelic variants are associated with brain calcification, suggesting that defective cell-to-cell adhesion and dysfunction of the movement of solutes through the paracellular spaces in the neurovascular unit is a key mechanism in CNS calcification.
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Abeti R, Zeitlberger A, Peelo C, Fassihi H, Sarkany RPE, Lehmann AR, Giunti P. Xeroderma pigmentosum: overview of pharmacology and novel therapeutic strategies for neurological symptoms. Br J Pharmacol 2019; 176:4293-4301. [PMID: 30499105 DOI: 10.1111/bph.14557] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 08/06/2018] [Accepted: 09/19/2018] [Indexed: 12/11/2022] Open
Abstract
Xeroderma pigmentosum (XP) encompasses a group of rare diseases characterized in most cases by malfunction of nucleotide excision repair (NER), which results in an increased sensitivity to UV radiation in affected individuals. Approximately 25-30% of XP patients present with neurological symptoms, such as sensorineural deafness, mental deterioration and ataxia. Although it is known that dysfunctional DNA repair is the primary pathogenesis in XP, growing evidence suggests that mitochondrial pathophysiology may also occur. This appears to be secondary to dysfunctional NER but may contribute to the neurodegenerative process in these patients. The available pharmacological treatments in XP mostly target the dermal manifestations of the disease. In the present review, we outline how current understanding of the pathophysiology of XP could be used to develop novel therapies to counteract the neurological symptoms. Moreover, the coexistence of cancer and neurodegeneration present in XP led us to focus on possible new avenues targeting mitochondrial pathophysiology. LINKED ARTICLES: This article is part of a themed section on Mitochondrial Pharmacology: Featured Mechanisms and Approaches for Therapy Translation. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.22/issuetoc.
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Affiliation(s)
- Rosella Abeti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, University College London, Institute of Neurology London, London, UK
| | - Anna Zeitlberger
- Ataxia Centre, Department of Clinical and Movement Neurosciences, University College London, Institute of Neurology London, London, UK
| | - Colm Peelo
- Ataxia Centre, Department of Clinical and Movement Neurosciences, University College London, Institute of Neurology London, London, UK
| | - Hiva Fassihi
- National Xeroderma Pigmentosum Service, St John's Institute of Dermatology Guy's and St Thomas' Foundation Trust, London, UK
| | - Robert P E Sarkany
- National Xeroderma Pigmentosum Service, St John's Institute of Dermatology Guy's and St Thomas' Foundation Trust, London, UK
| | - Alan R Lehmann
- Genome Damage and Stability Centre, University of Sussex, Brighton, UK
| | - Paola Giunti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, University College London, Institute of Neurology London, London, UK.,National Xeroderma Pigmentosum Service, St John's Institute of Dermatology Guy's and St Thomas' Foundation Trust, London, UK
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7
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Nethisinghe S, Lim WN, Ging H, Zeitlberger A, Abeti R, Pemble S, Sweeney MG, Labrum R, Cervera C, Houlden H, Rosser E, Limousin P, Kennedy A, Lunn MP, Bhatia KP, Wood NW, Hardy J, Polke JM, Veneziano L, Brusco A, Davis MB, Giunti P. Complexity of the Genetics and Clinical Presentation of Spinocerebellar Ataxia 17. Front Cell Neurosci 2018; 12:429. [PMID: 30532692 PMCID: PMC6265347 DOI: 10.3389/fncel.2018.00429] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 10/30/2018] [Indexed: 12/31/2022] Open
Abstract
Spinocerebellar ataxia type 17 (SCA17) is a rare autosomal dominant neurodegenerative disease caused by a CAG repeat expansion in the TATA-box binding protein gene (TBP). The disease has a varied age at onset and clinical presentation. It is distinct from other SCAs for its association with dementia, psychiatric symptoms, and some patients presenting with chorea. For this reason, it is also called Huntington’s disease-like 4 (HDL-4). Here we examine the distribution of SCA17 allele repeat sizes in a United Kingdom-based cohort with ataxia and find that fully penetrant pathogenic alleles are very rare (5 in 1,316 chromosomes; 0.38%). Phenotype-genotype correlation was performed on 30 individuals and the repeat structure of their TBP genes was examined. We found a negative linear correlation between total CAG repeat length and age at disease onset and, unlike SCA1, there was no correlation between the longest contiguous CAG tract and age at disease onset. We were unable to identify any particular phenotypic trait that segregated with particular CAG/CAA repeat tract structures or repeat lengths. One individual within the cohort was homozygous for variable penetrance range SCA17 alleles. This patient had a similar age at onset to heterozygotes with the same repeat sizes, but also presented with a rapidly progressive dementia. A pair of monozygotic twins within the cohort presented 3 years apart with the sibling with the earlier onset having a more severe phenotype with dementia and chorea in addition to the ataxia observed in their twin. This appears to be a case of variable expressivity, possibly influenced by other environmental or epigenetic factors. Finally, there was an asymptomatic father with a severely affected child with an age at onset in their twenties. Despite this, they share the same expanded allele repeat sizes and sequences, which would suggest that there is marked difference in the penetrance of this 51-repeat allele. We therefore propose that the variable penetrance range extend from 48 repeats to incorporate this allele. This study shows that there is variability in the presentation and penetrance of the SCA17 phenotype and highlights the complexity of this disorder.
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Affiliation(s)
- Suran Nethisinghe
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Wei N Lim
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Heather Ging
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Anna Zeitlberger
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Rosella Abeti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Sally Pemble
- Neurogenetics Unit, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Mary G Sweeney
- Neurogenetics Unit, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Robyn Labrum
- Neurogenetics Unit, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Charisse Cervera
- Neurogenetics Unit, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Henry Houlden
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom.,MRC Centre for Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Elisabeth Rosser
- Department of Clinical Genetics, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Patricia Limousin
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Angus Kennedy
- Chelsea and Westminster Hospital, London, United Kingdom
| | - Michael P Lunn
- Department of Neuroimmunology, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Kailash P Bhatia
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Nicholas W Wood
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - John Hardy
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, United Kingdom.,The Reta Lila Weston Institute of Neurological Studies, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - James M Polke
- Neurogenetics Unit, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Liana Veneziano
- Istituto di Farmacologia Traslazionale - National Research Council, Rome, Italy
| | - Alfredo Brusco
- Department of Medical Sciences, University of Turin, Turin, Italy.,Medical Genetics Unit, Città della Salute e della Scienza University Hospital, Turin, Italy
| | - Mary B Davis
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Paola Giunti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, United Kingdom
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Abeti R, Brown AF, Maiolino M, Patel S, Giunti P. Calcium Deregulation: Novel Insights to Understand Friedreich's Ataxia Pathophysiology. Front Cell Neurosci 2018; 12:264. [PMID: 30333728 PMCID: PMC6176067 DOI: 10.3389/fncel.2018.00264] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 08/02/2018] [Indexed: 12/21/2022] Open
Abstract
Friedreich's Ataxia (FRDA) is a neurodegenerative disorder, characterized by degeneration of dorsal root ganglia, cerebellum and cardiomyopathy. Heart failure is one of the most common causes of death for FRDA patients. Deficiency of frataxin, a small mitochondrial protein, is responsible for all clinical and morphological manifestations of FRDA. The focus of our study was to investigate the unexplored Ca2+ homeostasis in cerebellar granule neurons (CGNs) and in cardiomyocytes of FRDA cellular models to understand the pathogenesis of degeneration. Ca2+ homeostasis in neurons and cardiomyocytes is not only crucial for the cellular wellbeing but more importantly to generate action potential in both neurons and cardiomyocytes. By challenging Ca2+ homeostasis in CGNs, and in adult and neonatal cardiomyocytes of FRDA models, we have assessed the impact of frataxin decrease on both neuronal and cardiac physiopathology. Interestingly, we have found that Ca2+ homeostasis is altered both cell types. CGNs showed a Ca2+ mishandling under depolarizing conditions and this was also reflected in the endoplasmic reticulum (ER) content. In cardiomyocytes we found that the sarcoplasmic reticulum (SR) Ca2+ content was pathologically reduced, and that mitochondrial Ca2+ uptake was impaired. This phenomenon is due to the excess of oxidative stress under FRDA like conditions and the consequent aberrant modulation of key players at the SR/ER and mitochondrial level that usually restore the Ca2+ homeostasis. Our findings demonstrate that in both neurons and cardiomyocytes the decreased Ca2+ level within the stores has a comparable detrimental impact in their physiology. In cardiomyocytes, we found that ryanodine receptors (RyRs) may be leaking and expel more Ca2+ out from the SR. At the same time mitochondrial uptake was altered and we found that Vitamin E can restore this defect. Moreover, Vitamin E protects from cell death induced by hypoxia-reperfusion injury, revealing novel properties of Vitamin E as potential therapeutic tool for FRDA cardiomyopathy.
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Affiliation(s)
- Rosella Abeti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, Institute of Neurology, University College London, London, United Kingdom
| | - Alexander F Brown
- Ataxia Centre, Department of Clinical and Movement Neurosciences, Institute of Neurology, University College London, London, United Kingdom
| | - Marta Maiolino
- Department of Biomedical Sciences and Public Health, School of Medicine, Università Politecnica delle Marche, Ancona, Italy
| | - Sandip Patel
- Department of Cell and Developmental Biology, Division of Biosciences, University College London, London, United Kingdom
| | - Paola Giunti
- Ataxia Centre, Department of Clinical and Movement Neurosciences, Institute of Neurology, University College London, London, United Kingdom
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Abeti R, Baccaro A, Esteras N, Giunti P. Novel Nrf2-Inducer Prevents Mitochondrial Defects and Oxidative Stress in Friedreich's Ataxia Models. Front Cell Neurosci 2018; 12:188. [PMID: 30065630 PMCID: PMC6056642 DOI: 10.3389/fncel.2018.00188] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 06/11/2018] [Indexed: 12/30/2022] Open
Abstract
Friedreich’s Ataxia (FRDA) is an autosomal recessive neurodegenerative disorder, affecting dorsal root ganglia (DRG), cerebellar dentate nuclei and heart. It is caused by a GAA repeat expansion mutation within the frataxin gene (FXN). This impedes FXN transcription resulting in a progressive decrease of the mitochondrial protein, frataxin. Increased oxidative stress leading to a chronic depletion of endogenous antioxidants affects the survival of the cells and causes neurodegeneration. In particular, cerebellar granule neurons (CGNs) show a significant increase of reactive oxygen species (ROS), lipid peroxidation and lower level of reduced glutathione (GSH). In FRDA, one of the major pathways of oxidant scavengers, the Nrf2 antioxidant pathway, is defective. Previous studies on FRDA-like CGNs showed that the reduced level of frataxin and the oxidative stress induce mitochondrial impairments. By triggering the Nrf2 endogenous pathway pharmacologically we determined whether this could promote mitochondrial fitness and counteract oxidative stress. In this work, we sought to investigate the beneficial effect of a promising Nrf2-inducer, omaveloxolone (omav), in CGNs from two FRDA mouse models, KIKO and YG8R, and human fibroblasts from patients. We found that CGNs from both KIKO and YG8R presented Complex I deficiency and that omav was able to restore substrate availability and Complex I activity. This was also confirmed in human primary fibroblasts from FRDA patients. Although fibroblasts are not the major tissue affected, we found that they show significant differences recapitulating the disease; this is therefore an important tool to investigate patients’ pathophysiology. Interestingly, we found that patient fibroblasts had an increased level of endogenous lipid peroxidation and mitochondrial ROS (mROS), and lower GSH at rest. Omav was able to reverse this phenotype, protecting the cells against oxidative stress. By stimulating the cells with hydrogen peroxide (H2O2) and looking for potential mitochondrial pathophysiology, we found that fibroblasts could not maintain their mitochondrial membrane potential (ΔΨm). Remarkably, omav was protective to mitochondrial depolarization, promoting mitochondrial respiration and preventing cell death. Our results show that omav promotes Complex I activity and protect cells from oxidative stress. Omav could, therefore, be used as a novel therapeutic drug to ameliorate the pathophysiology of FRDA.
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Affiliation(s)
- Rosella Abeti
- Ataxia Centre, Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
| | - Annalisa Baccaro
- Ataxia Centre, Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
| | - Noemi Esteras
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
| | - Paola Giunti
- Ataxia Centre, Department of Molecular Neuroscience, UCL Institute of Neurology, London, United Kingdom
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Parviainen L, Dihanich S, Anderson GW, Wong AM, Brooks HR, Abeti R, Rezaie P, Lalli G, Pope S, Heales SJ, Mitchison HM, Williams BP, Cooper JD. Glial cells are functionally impaired in juvenile neuronal ceroid lipofuscinosis and detrimental to neurons. Acta Neuropathol Commun 2017; 5:74. [PMID: 29041969 PMCID: PMC5645909 DOI: 10.1186/s40478-017-0476-y] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 09/23/2017] [Indexed: 11/18/2022] Open
Abstract
The neuronal ceroid lipofuscinoses (NCLs or Batten disease) are a group of inherited, fatal neurodegenerative disorders of childhood. In these disorders, glial (microglial and astrocyte) activation typically occurs early in disease progression and predicts where neuron loss subsequently occurs. We have found that in the most common juvenile form of NCL (CLN3 disease or JNCL) this glial response is less pronounced in both mouse models and human autopsy material, with the morphological transformation of both astrocytes and microglia severely attenuated or delayed. To investigate their properties, we isolated glia and neurons from Cln3-deficient mice and studied their basic biology in culture. Upon stimulation, both Cln3-deficient astrocytes and microglia also showed an attenuated ability to transform morphologically, and an altered protein secretion profile. These defects were more pronounced in astrocytes, including the reduced secretion of a range of neuroprotective factors, mitogens, chemokines and cytokines, in addition to impaired calcium signalling and glutamate clearance. Cln3-deficient neurons also displayed an abnormal organization of their neurites. Most importantly, using a co-culture system, Cln3-deficient astrocytes and microglia had a negative impact on the survival and morphology of both Cln3-deficient and wildtype neurons, but these effects were largely reversed by growing mutant neurons with healthy glia. These data provide evidence that CLN3 disease astrocytes are functionally compromised. Together with microglia, they may play an active role in neuron loss in this disorder and can be considered as potential targets for therapeutic interventions.
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Bradshaw TY, Romano LEL, Duncan EJ, Nethisinghe S, Abeti R, Michael GJ, Giunti P, Vermeer S, Chapple JP. A reduction in Drp1-mediated fission compromises mitochondrial health in autosomal recessive spastic ataxia of Charlevoix Saguenay. Hum Mol Genet 2016; 25:3232-3244. [PMID: 27288452 PMCID: PMC5179924 DOI: 10.1093/hmg/ddw173] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 05/07/2016] [Accepted: 05/09/2016] [Indexed: 11/14/2022] Open
Abstract
The neurodegenerative disease autosomal recessive spastic ataxia of Charlevoix Saguenay (ARSACS) is caused by loss of function of sacsin, a modular protein that is required for normal mitochondrial network organization. To further understand cellular consequences of loss of sacsin, we performed microarray analyses in sacsin knockdown cells and ARSACS patient fibroblasts. This identified altered transcript levels for oxidative phosphorylation and oxidative stress genes. These changes in mitochondrial gene networks were validated by quantitative reverse transcription PCR. Functional impairment of oxidative phosphorylation was then demonstrated by comparison of mitochondria bioenergetics through extracellular flux analyses. Moreover, staining with the mitochondrial-specific fluorescent probe MitoSox suggested increased levels of superoxide in patient cells with reduced levels of sacsin.Key to maintaining mitochondrial health is mitochondrial fission, which facilitates the dynamic exchange of mitochondrial components and separates damaged parts of the mitochondrial network for selective elimination by mitophagy. Fission is dependent on dynamin-related protein 1 (Drp1), which is recruited to prospective sites of division where it mediates scission. In sacsin knockdown cells and ARSACS fibroblasts, we observed a decreased incidence of mitochondrial associated Drp1 foci. This phenotype persists even when fission is induced by drug treatment. Mitochondrial-associated Drp1 foci are also smaller in sacsin knockdown cells and ARSACS fibroblasts. These data suggest a model for ARSACS where neurons with reduced levels of sacsin are compromised in their ability to recruit or retain Drp1 at the mitochondrial membrane leading to a decline in mitochondrial health, potentially through impaired mitochondrial quality control.
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Affiliation(s)
- Teisha Y Bradshaw
- William Harvey Research Institute, Barts and the London School of Medicine, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Lisa E L Romano
- William Harvey Research Institute, Barts and the London School of Medicine, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Emma J Duncan
- William Harvey Research Institute, Barts and the London School of Medicine, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Suran Nethisinghe
- William Harvey Research Institute, Barts and the London School of Medicine, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Rosella Abeti
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3BG, United Kingdom
| | - Gregory J Michael
- Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, United Kingdom
| | - Paola Giunti
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3BG, United Kingdom
| | - Sascha Vermeer
- Department of Clinical Genetics, The Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - J Paul Chapple
- William Harvey Research Institute, Barts and the London School of Medicine, Queen Mary University of London, London EC1M 6BQ, United Kingdom
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Abeti R, Parkinson MH, Hargreaves IP, Angelova PR, Sandi C, Pook MA, Giunti P, Abramov AY. 'Mitochondrial energy imbalance and lipid peroxidation cause cell death in Friedreich's ataxia'. Cell Death Dis 2016; 7:e2237. [PMID: 27228352 PMCID: PMC4917650 DOI: 10.1038/cddis.2016.111] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 04/04/2016] [Accepted: 03/16/2016] [Indexed: 12/27/2022]
Abstract
Friedreich's ataxia (FRDA) is an inherited neurodegenerative disease. The mutation consists of a GAA repeat expansion within the FXN gene, which downregulates frataxin, leading to abnormal mitochondrial iron accumulation, which may in turn cause changes in mitochondrial function. Although, many studies of FRDA patients and mouse models have been conducted in the past two decades, the role of frataxin in mitochondrial pathophysiology remains elusive. Are the mitochondrial abnormalities only a side effect of the increased accumulation of reactive iron, generating oxidative stress? Or does the progressive lack of iron-sulphur clusters (ISCs), induced by reduced frataxin, cause an inhibition of the electron transport chain complexes (CI, II and III) leading to reactive oxygen species escaping from oxidative phosphorylation reactions? To answer these crucial questions, we have characterised the mitochondrial pathophysiology of a group of disease-relevant and readily accessible neurons, cerebellar granule cells, from a validated FRDA mouse model. By using live cell imaging and biochemical techniques we were able to demonstrate that mitochondria are deregulated in neurons from the YG8R FRDA mouse model, causing a decrease in mitochondrial membrane potential (▵Ψm) due to an inhibition of Complex I, which is partially compensated by an overactivation of Complex II. This complex activity imbalance leads to ROS generation in both mitochondrial matrix and cytosol, which results in glutathione depletion and increased lipid peroxidation. Preventing this increase in lipid peroxidation, in neurons, protects against in cell death. This work describes the pathophysiological properties of the mitochondria in neurons from a FRDA mouse model and shows that lipid peroxidation could be an important target for novel therapeutic strategies in FRDA, which still lacks a cure.
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Affiliation(s)
- R Abeti
- Ataxia Centre, Department of Molecular Neuroscience, UCL, Institute of Neurology, Queen Square, London, UK
| | - M H Parkinson
- Ataxia Centre, Department of Molecular Neuroscience, UCL, Institute of Neurology, Queen Square, London, UK
| | | | - P R Angelova
- Department of Molecular Neuroscience, UCL, Institute of Neurology, Queen Square, London, UK
| | - C Sandi
- Ataxia Research Group, Division of Biosciences, Department of Life Sciences, College of Health & Life Sciences, and Synthetic Biology Theme, Institute of Environment, Health & Societies, Brunel University London, Uxbridge, UK
| | - M A Pook
- Ataxia Research Group, Division of Biosciences, Department of Life Sciences, College of Health & Life Sciences, and Synthetic Biology Theme, Institute of Environment, Health & Societies, Brunel University London, Uxbridge, UK
| | - P Giunti
- Ataxia Centre, Department of Molecular Neuroscience, UCL, Institute of Neurology, Queen Square, London, UK
| | - A Y Abramov
- Department of Molecular Neuroscience, UCL, Institute of Neurology, Queen Square, London, UK
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Abeti R, Parkinson MH, Hargreaves IP, Pook MA, Abramov AY, Giunti P. Understanding the Role of Mitochondrial Pathophysiology in Friedreich's Ataxia. Biophys J 2016. [DOI: 10.1016/j.bpj.2015.11.2534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Abeti R, Uzun E, Renganathan I, Honda T, Pook MA, Giunti P. Targeting lipid peroxidation and mitochondrial imbalance in Friedreich's ataxia. Pharmacol Res 2015; 99:344-50. [PMID: 26141703 DOI: 10.1016/j.phrs.2015.05.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 05/04/2015] [Accepted: 05/15/2015] [Indexed: 11/24/2022]
Abstract
Friedreich's ataxia (FRDA) is an autosomal recessive disorder, caused by reduced levels of the protein frataxin. This protein is located in the mitochondria, where it functions in the biogenesis of iron-sulphur clusters (ISCs), which are important for the function of the mitochondrial respiratory chain complexes. Moreover, disruption in iron biogenesis may lead to oxidative stress. Oxidative stress can be the cause and/or the consequence of mitochondrial energy imbalance, leading to cell death. Fibroblasts from two FRDA mouse models, YG8R and KIKO, were used to analyse two different categories of protective compounds: deuterised poly-unsaturated fatty acids (dPUFAs) and Nrf2-inducers. The former have been shown to protect the cell from damage induced by lipid peroxidation and the latter trigger the well-known Nrf2 antioxidant pathway. Our results show that the sensitivity to oxidative stress of YG8R and KIKO mouse fibroblasts, resulting in cell death and lipid peroxidation, can be prevented by d4-PUFA and Nrf2-inducers (SFN and TBE-31). The mitochondrial membrane potential (ΔΨm) of YG8R and KIKO fibroblasts revealed a difference in their mitochondrial pathophysiology, which may be due to the different genetic basis of the two models. This suggests that variable levels of reduced frataxin may act differently on mitochondrial pathophysiology and that these two cell models could be useful in recapitulating the observed differences in the FRDA phenotype. This may reflect a different modulatory effect towards cell death that will need to be investigated further.
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Affiliation(s)
- Rosella Abeti
- Department of Molecular Neuroscience, UCL, Institute of Neurology, Queen Square, WC1N 3BG London, UK
| | - Ebru Uzun
- Department of Molecular Neuroscience, UCL, Institute of Neurology, Queen Square, WC1N 3BG London, UK
| | - Indhushri Renganathan
- Department of Molecular Neuroscience, UCL, Institute of Neurology, Queen Square, WC1N 3BG London, UK
| | - Tadashi Honda
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794, United States
| | - Mark A Pook
- Ataxia Research Group, Division of Biosciences, Department of Life Sciences, College of Health & Life Sciences Synthetic Biology Theme, Institute of Environment, Health & Societies, Brunel University London, Uxbridge UB8 3PH, UK
| | - Paola Giunti
- Department of Molecular Neuroscience, UCL, Institute of Neurology, Queen Square, WC1N 3BG London, UK.
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15
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Abeti R, Abramov AY. Mitochondrial Ca2+ in neurodegenerative disorders. Pharmacol Res 2015; 99:377-81. [DOI: 10.1016/j.phrs.2015.05.007] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 05/11/2015] [Accepted: 05/15/2015] [Indexed: 01/08/2023]
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Gatliff J, East D, Crosby J, Abeti R, Harvey R, Craigen W, Parker P, Campanella M. TSPO interacts with VDAC1 and triggers a ROS-mediated inhibition of mitochondrial quality control. Autophagy 2014; 10:2279-96. [PMID: 25470454 PMCID: PMC4502750 DOI: 10.4161/15548627.2014.991665] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 09/17/2014] [Accepted: 09/22/2014] [Indexed: 01/03/2023] Open
Abstract
The 18-kDa TSPO (translocator protein) localizes on the outer mitochondrial membrane (OMM) and participates in cholesterol transport. Here, we report that TSPO inhibits mitochondrial autophagy downstream of the PINK1-PARK2 pathway, preventing essential ubiquitination of proteins. TSPO abolishes mitochondrial relocation of SQSTM1/p62 (sequestosome 1), and consequently that of the autophagic marker LC3 (microtubule-associated protein 1 light chain 3), thus leading to an accumulation of dysfunctional mitochondria, altering the appearance of the network. Independent of cholesterol regulation, the modulation of mitophagy by TSPO is instead dependent on VDAC1 (voltage-dependent anion channel 1), to which TSPO binds, reducing mitochondrial coupling and promoting an overproduction of reactive oxygen species (ROS) that counteracts PARK2-mediated ubiquitination of proteins. These data identify TSPO as a novel element in the regulation of mitochondrial quality control by autophagy, and demonstrate the importance for cell homeostasis of its expression ratio with VDAC1.
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Key Words
- ATP5B, ATP synthase, H+ transporting, mitochondrial F1 complex, β subunit
- DAPI, 4’, 6-diamidino-2-phenylindole
- DHE, dihydroethidium
- DNM1L, dynamin 1-like
- FCCP, carbonyl cyanide-4-(trifluoromethoxy)phenylhydrazone
- GAPDH, glyceraldehyde-3-phosphate dehydrogenase
- GSH, glutathione
- MAP1LC3/LC3, microtubule-associated protein 1 light chain 3
- MCB, monochlorobimane
- MEFs, mouse embryonic fibroblasts
- MnTBAP, manganese [III] tetrakis (4-benzoic acid) porphyrin
- MβCD, methyl-β-cyclodextrin
- NRF1, nuclear respiratory factor 1
- OMM, outer mitochondrial membrane
- PARK2
- PBS, phosphate-buffered saline
- PINK1, PTEN-induced putative kinase 1
- PRKCE, protein kinase C, epsilon
- RM, recording medium
- ROS
- ROS, reactive oxygen species
- RT, room temperature
- SQSTM1, sequestosome 1
- TFAM, transcription factor A, mitochondrial
- TMRM, tetramethylrhodamine methyl ester
- TSPO
- TSPO, translocator protein
- VDAC1, voltage-dependent anion channel 1
- YFP, yellow fluorescent protein
- mitochondria
- mitophagy
- mtRFP, mitochondrially targeted red fluorescent protein
- nsc, nonsilencing control
- siRNA, small interfering ribonucleic acid
- ubiquitin
- Δψm, mitochondrial membrane potential
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Affiliation(s)
- Jemma Gatliff
- Department of Comparative Biomedical Sciences; The Royal Veterinary College; University of London; London, UK
| | - Daniel East
- Department of Comparative Biomedical Sciences; The Royal Veterinary College; University of London; London, UK
| | - James Crosby
- Department of Comparative Biomedical Sciences; The Royal Veterinary College; University of London; London, UK
| | | | - Robert Harvey
- Department of Pharmacology; UCL School of Pharmacy; London, UK
| | - William Craigen
- Department of Molecular and Human Genetics; Baylor College of Medicine; Houston, TX USA
| | - Peter Parker
- London Research Institute; Lincoln's Inn Fields Laboratories; London, UK
- Division of Cancer Studies; King's College; London, UK
| | - Michelangelo Campanella
- Department of Comparative Biomedical Sciences; The Royal Veterinary College; University of London; London, UK
- University College London Consortium for Mitochondrial Research; London, UK
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Manzoni C, Mamais A, Dihanich S, Abeti R, Soutar MPM, Plun-Favreau H, Giunti P, Tooze SA, Bandopadhyay R, Lewis PA. Inhibition of LRRK2 kinase activity stimulates macroautophagy. Biochim Biophys Acta 2013; 1833:2900-2910. [PMID: 23916833 PMCID: PMC3898616 DOI: 10.1016/j.bbamcr.2013.07.020] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 07/19/2013] [Accepted: 07/23/2013] [Indexed: 02/05/2023]
Abstract
Leucine Rich Repeat Kinase 2 (LRRK2) is one of the most important genetic contributors to Parkinson's disease. LRRK2 has been implicated in a number of cellular processes, including macroautophagy. To test whether LRRK2 has a role in regulating autophagy, a specific inhibitor of the kinase activity of LRRK2 was applied to human neuroglioma cells and downstream readouts of autophagy examined. The resulting data demonstrate that inhibition of LRRK2 kinase activity stimulates macroautophagy in the absence of any alteration in the translational targets of mTORC1, suggesting that LRRK2 regulates autophagic vesicle formation independent of canonical mTORC1 signaling. This study represents the first pharmacological dissection of the role LRRK2 plays in the autophagy/lysosomal pathway, emphasizing the importance of this pathway as a marker for LRRK2 physiological function. Moreover it highlights the need to dissect autophagy and lysosomal activities in the context of LRRK2 related pathologies with the final aim of understanding their aetiology and identifying specific targets for disease modifying therapies in patients.
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Affiliation(s)
- Claudia Manzoni
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK.
| | - Adamantios Mamais
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK; Reta Lila Weston Institute and Queen Square Brain Bank, UCL Institute of Neurology, 1 Wakefield Street, London, WC1N 1PJ, UK
| | - Sybille Dihanich
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Rosella Abeti
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Marc P M Soutar
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Helene Plun-Favreau
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Paola Giunti
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Sharon A Tooze
- London Research Institute, Cancer Research UK, Lincoln's Inn Fields, London, WC2A 3LY, UK
| | - Rina Bandopadhyay
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK; Reta Lila Weston Institute and Queen Square Brain Bank, UCL Institute of Neurology, 1 Wakefield Street, London, WC1N 1PJ, UK
| | - Patrick A Lewis
- Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK; School of Pharmacy, University of Reading, Whiteknights, Reading, RG6 6AP, UK.
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Averaimo S, Abeti R, Savalli N, Brown LJ, Curmi PMG, Breit SN, Mazzanti M. Point mutations in the transmembrane region of the clic1 ion channel selectively modify its biophysical properties. PLoS One 2013; 8:e74523. [PMID: 24058583 PMCID: PMC3776819 DOI: 10.1371/journal.pone.0074523] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 08/02/2013] [Indexed: 12/16/2022] Open
Abstract
Chloride intracellular Channel 1 (CLIC1) is a metamorphic protein that changes from a soluble cytoplasmic protein into a transmembrane protein. Once inserted into membranes, CLIC1 multimerises and is able to form chloride selective ion channels. Whilst CLIC1 behaves as an ion channel both in cells and in artificial lipid bilayers, its structure in the soluble form has led to some uncertainty as to whether it really is an ion channel protein. CLIC1 has a single putative transmembrane region that contains only two charged residues: arginine 29 (Arg29) and lysine 37 (Lys37). As charged residues are likely to have a key role in ion channel function, we hypothesized that mutating them to neutral alanine to generate K37A and R29A CLIC1 would alter the electrophysiological characteristics of CLIC1. By using three different electrophysiological approaches: i) single channel Tip-Dip in artificial bilayers using soluble recombinant CLIC1, ii) cell-attached and iii) whole-cell patch clamp recordings in transiently transfected HEK cells, we determined that the K37A mutation altered the single-channel conductance while the R29A mutation affected the single-channel open probability in response to variation in membrane potential. Our results show that mutation of the two charged amino acids (K37 and R29) in the putative transmembrane region of CLIC1 alters the biophysical properties of the ion channel in both artificial bilayers and cells. Hence these charged residues are directly involved in regulating its ion channel activity. This strongly suggests that, despite its unusual structure, CLIC1 itself is able to form a chloride ion channel.
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Affiliation(s)
- Stefania Averaimo
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milan, Italy
- * E-mail:
| | - Rosella Abeti
- Department of Molecular Neuroscience, University College London, Institute of Neurology, London, United Kingdom
| | - Nicoletta Savalli
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milan, Italy
| | - Louise J. Brown
- Department of Chemistry and Biomolecular Sciences, Macquarie University, Sydney, Australia
| | - Paul M. G. Curmi
- School of Physics, University of New South Wales, Sydney, Australia
- St Vincent’s Centre for Applied Medical Research, St Vincent’s Hospital, Sydney, Australia
| | - Samuel N. Breit
- St Vincent’s Centre for Applied Medical Research, St Vincent’s Hospital, Sydney, Australia
| | - Michele Mazzanti
- Dipartimento di Bioscienze, Università degli Studi di Milano, Milan, Italy
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Abeti R, Duchen MR. Activation of PARP by oxidative stress induced by β-amyloid: implications for Alzheimer's disease. Neurochem Res 2012; 37:2589-96. [PMID: 23076628 DOI: 10.1007/s11064-012-0895-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Revised: 09/21/2012] [Accepted: 09/21/2012] [Indexed: 01/11/2023]
Abstract
Alzheimer's disease (AD) is a major neurodegenerative disease of old age, characterised by progressive cognitive impairment, dementia and atrophy of the central nervous system. The pathological hallmarks include the accumulation of the peptide β-amyloid (Aβ) which itself is toxic to neurons in culture. Recently, it has been discovered that Aβ activates the protein poly(ADP-ribosyl) polymerase-1 (PARP-1) specifically in astrocytes, leading indirectly to neuronal cell death. PARP-1 is a DNA repair enzyme, normally activated by single strand breaks associated with oxidative stress, which catalyses the formation of poly ADP-ribose polymers from nicotinamide adenine dinucleotide (NAD(+)). The pathological over activation of PARP-1 causes depletion of NAD(+) and leads to cell death. Here we review the relationship between AD and PARP-1, and explore the role played by astrocytes in neuronal death. AD has so far proven refractory to any effective treatment. Identification of these pathways represents a step towards a greater understanding of the pathophysiology of this devastating disease with the potential to explore novel therapeutic targets.
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Affiliation(s)
- Rosella Abeti
- Department of Molecular Neuroscience, Institute of Neurology, UCL, Queen Square, London, WC1N 3BG, UK.
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Abstract
Alzheimer's disease is characterized by β-amyloid accumulation in the central nervous system. As β-amyloid is neurotoxic in culture, we have explored the mechanisms of toxicity in the search for therapeutic targets for Alzheimer's disease and now identify a key role for poly(ADP-ribose) polymerase in β-amyloid-induced neuronal death. Exposure of hippocampal neuronal/glial co-cultures to β-amyloid peptides activates the glial nicotinamide adenine dinucleotide phosphate oxidase, followed by predominantly neuronal cell death. β-amyloid exposure caused the progressive loss of mitochondrial membrane potential in astrocytes, accompanied by transient mitochondrial depolarizations caused by reversible openings of the mitochondrial permeability transition pore. The transients were absent in cultures from cyclophilin D knockout mice, leaving the slow depolarization available for study in isolation. β-amyloid exposure decreased both nicotinamide adenine dinucleotide fluorescence and oxygen consumption, while provision of mitochondrial substrates reversed the depolarization, suggesting that substrate supply was limiting. Poly(ADP-ribose) polymerase is activated by oxidative stress and consumes nicotinamide adenine dinucleotide, decreasing substrate availability. β-amyloid exposure caused accumulation of the poly(ADP-ribose) polymerase product, poly-ADP-ribose polymers, in astrocytes. Inhibition of either poly(ADP-ribose) polymerase or of the nicotinamide adenine dinucleotide phosphate oxidase prevented the appearance of poly-ADP-ribose polymers and the mitochondrial depolarization. Exposure of co-cultures to β-amyloid for >8 h decreased nicotinamide adenine dinucleotide and mitochondrial membrane potential and increased cell death in neurons, all of which were prevented by poly(ADP-ribose) polymerase inhibitors. Poly-ADP-ribose polymers increased with age in the brains of the TASTPM Alzheimer mouse model. We conclude that β-amyloid-induced neuronal death is mediated by poly(ADP-ribose) polymerase in response to oxidative stress generated by the astrocytic nicotinamide adenine dinucleotide phosphate oxidase.
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Affiliation(s)
- Rosella Abeti
- Department of Cell and Developmental Biology and UCL Consortium for Mitochondrial Research, University College London, Queen Square, London WC1N 3BG, UK
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Campanella M, Seraphim A, Abeti R, Casswell E, Echave P, Duchen MR. IF1, the endogenous regulator of the F(1)F(o)-ATPsynthase, defines mitochondrial volume fraction in HeLa cells by regulating autophagy. Biochim Biophys Acta 2009; 1787:393-401. [PMID: 19269273 DOI: 10.1016/j.bbabio.2009.02.023] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2008] [Revised: 02/23/2009] [Accepted: 02/24/2009] [Indexed: 10/21/2022]
Abstract
The protein IF1 limits mitochondrial ATP consumption when mitochondrial respiration is impaired by inhibiting the 'reverse' activity of the F(1)F(o)-ATPsynthase. We have found that IF1 also increases F(1)F(o)-ATPsynthase activity in respiring mitochondria, promoting its dimerization and increasing the density of mitochondrial cristae. We also noted that IF1 overexpression was associated with an increase in mitochondrial volume fraction that was conversely reduced when IF1 was knocked down using small interfering RNA (siRNA). The volume change did not correlate with the level of transcription factors involved in mitochondrial biogenesis. However, autophagy was dramatically increased in the IF1siRNA treated cells (-IF1), assessed by quantifying LC3-GFP translocation to autophagosomes, whilst levels of autophagy were low in IF1 overexpressing cells (+IF1). The increase in LC3-GFP labelled autophagosomes in -IF1 cells was prevented by the superoxide dismutase mimetic, manganese (III) tetrakis (4-benzoic acid) porphyrin (MnTBAP). An increase in the basal rate of generation of reactive oxygen species (ROS) in -IF1 cells was demonstrated using the fluorescent probe dihydroethidium (DHE). Thus, IF1 appears to limit mitochondrial ROS generation, limiting autophagy which is increased by IF1 knockdown. Variations in IF1 expression level may therefore play a significant role in defining both resting rates of ROS generation and cellular mitochondrial content.
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Paradisi S, Matteucci A, Fabrizi C, Denti MA, Abeti R, Breit SN, Malchiodi-Albedi F, Mazzanti M. Blockade of chloride intracellular ion channel 1 stimulates Abeta phagocytosis. J Neurosci Res 2008; 86:2488-98. [PMID: 18438938 DOI: 10.1002/jnr.21693] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
In amyloid-beta (Abeta)-stimulated microglial cells, blockade of chloride intracellular ion channel 1 (CLIC1) reverts the increase in tumor necrosis factor-alpha and nitric oxide (NO) production and results in neuroprotection of cocultured neurons. This effect could be of therapeutic efficacy in Alzheimer's disease (AD), where microglial activation may contribute to neurodegeneration, but it could reduce Abeta phagocytosis, which could facilitate amyloid plaque removal. Here, we analyzed the CLIC1 blockade effect on Abeta-stimulated mononuclear phagocytosis. In the microglial cell line BV-2, Abeta25-35 treatment enhanced fluorescent bead phagocytosis, which persisted also in the presence of IAA-94, a CLIC1 channel blocker. The same result was obtained in rat primary microglia and in BV2 cells, where CLIC1 expression had been knocked down with a plasmid producing small interfering RNAs. To address specifically the issue of Abeta phagocytosis, we treated BV-2 cells with biotinylated Abeta1-42 and measured intracellular amyloid by morphometric analysis. IAA-94-treated cells showed an increased Abeta phagocytosis after 24 hr and efficient degradation of ingested material after 72 hr. In addition, we tested Abeta1-42 phagocytosis in adult rat peritoneal macrophages. Also, these cells actively phagocytosed Abeta1-42 in the presence of IAA-94. However, the increased expression of inducible NO synthase (iNOS), stimulated by Abeta, was reverted by IAA-94. In parallel, a decrease in NO release was detected. These results suggest that blockade of CLIC1 stimulates Abeta phagocytosis in mononuclear phagocytes while inhibiting the induction of iNOS and further point to CLIC1 as a possible therapeutic target in AD.
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Affiliation(s)
- Silvia Paradisi
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Rome, Italy
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Marchionni I, Paffi A, Pellegrino M, Liberti M, Apollonio F, Abeti R, Fontana F, D'Inzeo G, Mazzanti M. Comparison between low-level 50 Hz and 900 MHz electromagnetic stimulation on single channel ionic currents and on firing frequency in dorsal root ganglion isolated neurons. Biochimica et Biophysica Acta (BBA) - Biomembranes 2006; 1758:597-605. [PMID: 16713990 DOI: 10.1016/j.bbamem.2006.03.014] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2005] [Revised: 03/13/2006] [Accepted: 03/14/2006] [Indexed: 11/23/2022]
Abstract
Alteration of membrane surface charges represents one of the most interesting effects of the electromagnetic exposure on biological structures. Some evidence exists in the case of extremely low frequency whereas the same effect in the radiofrequency range has not been detected. Changes in transmembrane voltages are probably responsible for the mobilization of intracellular calcium described in some previous studies but not confirmed in others. These controversial results may be due to the cell type under examination and/or to the permeability properties of the membranes. According to such a hypothesis, calcium oscillations would be a secondary effect due to the induced change in the membrane voltage and thus dependent on the characteristics of ionic channels present in a particular preparation. Calcium increases could suggest more than one mechanism to explain the biological effects of exposure due to the fact that all the cellular pathways using calcium ions as a second messenger could be, in theory, disturbed by the electromagnetic field exposure. In the present work, we investigate the early phase of the signal transmission in the peripheral nervous system. We present evidence that the firing rate of rat sensory neurons can be modified by 50/60 Hz magnetic field but not by low level 900 MHz fields. The action of the 50/60 Hz magnetic field is biphasic. At first, the number of action potentials increases in time. Following this early phase, the firing rate decreases more rapidly than in control conditions. The explanation can be found at the single-channel level. Dynamic action current recordings in dorsal root ganglion neurons acutely exposed to the electromagnetic field show increased functionality of calcium channels. In parallel, a calcium-activated potassium channel is able to increase its mean open time.
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Affiliation(s)
- I Marchionni
- Dipartimento di Biologia Cellulare e dello Sviluppo Università La Sapienza, P.le Aldo Moro 5, I-00185 Roma, Italy
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