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Sarawi WS, Attia HA, Alomar HA, Alhaidar R, Rihan E, Aldurgham N, Ali RA. The protective role of sesame oil against Parkinson's-like disease induced by manganese in rats. Behav Brain Res 2024; 465:114969. [PMID: 38548024 DOI: 10.1016/j.bbr.2024.114969] [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: 12/07/2023] [Revised: 03/21/2024] [Accepted: 03/23/2024] [Indexed: 04/14/2024]
Abstract
Chronic exposure to manganese (Mn) results in motor dysfunction, biochemical and pathological alterations in the brain. Oxidative stress, inflammation, and dysfunction of dopaminergic and GABAergic systems stimulate activating transcription factor-6 (ATF-6) and protein kinase RNA-like ER kinase (PERK) leading to apoptosis. This study aimed to investigate the protective effect of sesame oil (SO) against Mn-induced neurotoxicity. Rats received 25 mg/kg MnCl2 and were concomitantly treated with 2.5, 5, or 8 ml/kg of SO for 5 weeks. Mn-induced motor dysfunction was indicated by significant decreases in the time taken by rats to fall during the rotarod test and in the number of movements observed during the open field test. Also, Mn resulted in neuronal degeneration as observed by histological staining. The striatal levels of lipid peroxides and reduced glutathione (oxidative stress markers), interleukin-6 and tumor necrosis factor-α (inflammatory markers) were significantly elevated. Mn significantly reduced the levels of dopamine and Bcl-2, while GABA, PERK, ATF-6, Bax, and caspase-3 were increased. Interestingly, all SO doses, especially at 8 ml/kg, significantly improved locomotor activity, biochemical deviations and reduced neuronal degeneration. In conclusion, SO may provide potential therapeutic benefits in enhancing motor performance and promoting neuronal survival in individuals highly exposed to Mn.
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Affiliation(s)
- Wedad S Sarawi
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia.
| | - Hala A Attia
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia
| | - Hatun A Alomar
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia
| | - Rawan Alhaidar
- College of Pharmacy, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia
| | - Esraa Rihan
- College of Pharmacy, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia
| | - Nora Aldurgham
- College of Pharmacy, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia
| | - Rehab A Ali
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia
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Huang M, Bargues-Carot A, Riaz Z, Wickham H, Zenitsky G, Jin H, Anantharam V, Kanthasamy A, Kanthasamy AG. Impact of Environmental Risk Factors on Mitochondrial Dysfunction, Neuroinflammation, Protein Misfolding, and Oxidative Stress in the Etiopathogenesis of Parkinson's Disease. Int J Mol Sci 2022; 23:ijms231810808. [PMID: 36142718 PMCID: PMC9505762 DOI: 10.3390/ijms231810808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/25/2022] [Accepted: 09/01/2022] [Indexed: 11/16/2022] Open
Abstract
As a prevalent progressive neurodegenerative disorder, Parkinson's disease (PD) is characterized by the neuropathological hallmark of the loss of nigrostriatal dopaminergic (DAergic) innervation and the appearance of Lewy bodies with aggregated α-synuclein. Although several familial forms of PD have been reported to be associated with several gene variants, most cases in nature are sporadic, triggered by a complex interplay of genetic and environmental risk factors. Numerous epidemiological studies during the past two decades have shown positive associations between PD and several environmental factors, including exposure to neurotoxic pesticides/herbicides and heavy metals as well as traumatic brain injury. Other environmental factors that have been implicated as potential risk factors for PD include industrial chemicals, wood pulp mills, farming, well-water consumption, and rural residence. In this review, we summarize the environmental toxicology of PD with the focus on the elaboration of chemical toxicity and the underlying pathogenic mechanisms associated with exposure to several neurotoxic chemicals, specifically 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), rotenone, paraquat (PQ), dichloro-diphenyl-trichloroethane (DDT), dieldrin, manganese (Mn), and vanadium (V). Our overview of the current findings from cellular, animal, and human studies of PD provides information for possible intervention strategies aimed at halting the initiation and exacerbation of environmentally linked PD.
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Affiliation(s)
- Minhong Huang
- Department of Biomedical Sciences, Iowa State University, 2062 Veterinary Medicine Building, Ames, IA 50011, USA
| | - Alejandra Bargues-Carot
- Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, 325 Riverbend Road, Athens, GA 30602, USA
| | - Zainab Riaz
- Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, 325 Riverbend Road, Athens, GA 30602, USA
| | - Hannah Wickham
- Department of Biomedical Sciences, Iowa State University, 2062 Veterinary Medicine Building, Ames, IA 50011, USA
| | - Gary Zenitsky
- Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, 325 Riverbend Road, Athens, GA 30602, USA
| | - Huajun Jin
- Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, 325 Riverbend Road, Athens, GA 30602, USA
| | - Vellareddy Anantharam
- Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, 325 Riverbend Road, Athens, GA 30602, USA
| | - Arthi Kanthasamy
- Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, 325 Riverbend Road, Athens, GA 30602, USA
| | - Anumantha G. Kanthasamy
- Department of Biomedical Sciences, Iowa State University, 2062 Veterinary Medicine Building, Ames, IA 50011, USA
- Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, 325 Riverbend Road, Athens, GA 30602, USA
- Correspondence: ; Tel.: +1-706-542-2380; Fax: +1-706-542-4412
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3
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Tuschl K, White RJ, Trivedi C, Valdivia LE, Niklaus S, Bianco IH, Dadswell C, González-Méndez R, Sealy IM, Neuhauss SCF, Houart C, Rihel J, Wilson SW, Busch-Nentwich EM. Loss of slc39a14 causes simultaneous manganese hypersensitivity and deficiency in zebrafish. Dis Model Mech 2022; 15:dmm044594. [PMID: 35514229 PMCID: PMC9227717 DOI: 10.1242/dmm.044594] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Accepted: 04/25/2022] [Indexed: 12/15/2022] Open
Abstract
Manganese neurotoxicity is a hallmark of hypermanganesemia with dystonia 2, an inherited manganese transporter defect caused by mutations in SLC39A14. To identify novel potential targets of manganese neurotoxicity, we performed transcriptome analysis of slc39a14-/- mutant zebrafish that were exposed to MnCl2. Differentially expressed genes mapped to the central nervous system and eye, and pathway analysis suggested that Ca2+ dyshomeostasis and activation of the unfolded protein response are key features of manganese neurotoxicity. Consistent with this interpretation, MnCl2 exposure led to decreased whole-animal Ca2+ levels, locomotor defects and changes in neuronal activity within the telencephalon and optic tectum. In accordance with reduced tectal activity, slc39a14-/- zebrafish showed changes in visual phototransduction gene expression, absence of visual background adaptation and a diminished optokinetic reflex. Finally, numerous differentially expressed genes in mutant larvae normalised upon MnCl2 treatment indicating that, in addition to neurotoxicity, manganese deficiency is present either subcellularly or in specific cells or tissues. Overall, we assembled a comprehensive set of genes that mediate manganese-systemic responses and found a highly correlated and modulated network associated with Ca2+ dyshomeostasis and cellular stress. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Karin Tuschl
- UCL GOS Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
- Department of Developmental Neurobiology and MRC Centre for Neurodevelopmental Disorders, IoPPN, Kings College London, New Hunt's House, Guy's Campus, London SE1 1UL, UK
| | - Richard J. White
- School of Biological and Behavioural Sciences, Faculty of Science and Engineering, Queen Mary University of London, London E1 4NS, UK
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Jeffrey Cheah Biomedical Centre, University of Cambridge, Puddicombe Way, Cambridge CB2 0AW, UK
| | - Chintan Trivedi
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Leonardo E. Valdivia
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
- Center for Integrative Biology, Facultad de Ciencias, Universidad Mayor, Camino La Pirámide 5750, Huechuraba 8580745, Chile
- Escuela de Biotecnología, Facultad de Ciencias, Universidad Mayor, Camino La Pirámide 5750, Huechuraba 8580745, Chile
| | - Stephanie Niklaus
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Isaac H. Bianco
- Department of Neuroscience, Physiology & Pharmacology, University College London, Gower Street, London WC1E 6BT, UK
| | - Chris Dadswell
- School of Life Sciences, University of Sussex, Brighton BN1 9QJ, UK
| | | | - Ian M. Sealy
- School of Biological and Behavioural Sciences, Faculty of Science and Engineering, Queen Mary University of London, London E1 4NS, UK
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Jeffrey Cheah Biomedical Centre, University of Cambridge, Puddicombe Way, Cambridge CB2 0AW, UK
| | - Stephan C. F. Neuhauss
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Corinne Houart
- Department of Developmental Neurobiology and MRC Centre for Neurodevelopmental Disorders, IoPPN, Kings College London, New Hunt's House, Guy's Campus, London SE1 1UL, UK
| | - Jason Rihel
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Stephen W. Wilson
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Elisabeth M. Busch-Nentwich
- School of Biological and Behavioural Sciences, Faculty of Science and Engineering, Queen Mary University of London, London E1 4NS, UK
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Jeffrey Cheah Biomedical Centre, University of Cambridge, Puddicombe Way, Cambridge CB2 0AW, UK
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4
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Scholefield M, Church SJ, Xu J, Patassini S, Roncaroli F, Hooper NM, Unwin RD, Cooper GJS. Widespread Decreases in Cerebral Copper Are Common to Parkinson's Disease Dementia and Alzheimer's Disease Dementia. Front Aging Neurosci 2021; 13:641222. [PMID: 33746735 PMCID: PMC7966713 DOI: 10.3389/fnagi.2021.641222] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 02/05/2021] [Indexed: 01/24/2023] Open
Abstract
Several studies of Parkinson's disease (PD) have reported dysregulation of cerebral metals, particularly decreases in copper and increases in iron in substantia nigra (SN). However, few studies have investigated regions outside the SN, fewer have measured levels of multiple metals across different regions within the same brains, and there are no currently-available reports of metal levels in Parkinson's disease dementia (PDD). This study aimed to compare concentrations of nine essential metals across nine different brain regions in cases of PDD and controls. Investigated were: primary motor cortex (MCX); cingulate gyrus (CG); primary visual cortex (PVC); hippocampus (HP); cerebellar cortex (CB); SN; locus coeruleus (LC); medulla oblongata (MED); and middle temporal gyrus (MTG), thus covering regions with severe, moderate, or low levels of neuronal loss in PDD. Levels of eight essential metals and selenium were determined using an analytical methodology involving the use of inductively-coupled plasma mass spectrometry (ICP-MS), and compared between cases and controls, to better understand the extent and severity of metal perturbations. Findings were also compared with those from our previous study of sporadic Alzheimer's disease dementia (ADD), which employed equivalent methods, to identify differences and similarities between these conditions. Widespread copper decreases occurred in PDD in seven of nine regions (exceptions being LC and CB). Four PDD-affected regions showed similar decreases in ADD: CG, HP, MTG, and MCX. Decreases in potassium and manganese were present in HP, MTG and MCX; decreased manganese was also found in SN and MED. Decreased selenium and magnesium were present in MCX, and decreased zinc in HP. There was no evidence for increased iron in SN or any other region. These results identify alterations in levels of several metals across multiple regions of PDD brain, the commonest being widespread decreases in copper that closely resemble those in ADD, pointing to similar disease mechanisms in both dementias.
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Affiliation(s)
- Melissa Scholefield
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, Centre for Advanced Discovery & Experimental Therapeutics, School of Medical Sciences, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Stephanie J. Church
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, Centre for Advanced Discovery & Experimental Therapeutics, School of Medical Sciences, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Jingshu Xu
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, Centre for Advanced Discovery & Experimental Therapeutics, School of Medical Sciences, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Stefano Patassini
- Faculty of Science, School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Federico Roncaroli
- Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Manchester, United Kingdom
- Division of Neuroscience and Experimental Psychology, Faculty of Brain and Mental Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Nigel M. Hooper
- Division of Neuroscience & Experimental Psychology, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, School of Biological Sciences, The University of Manchester, Manchester, United Kingdom
| | - Richard D. Unwin
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, Centre for Advanced Discovery & Experimental Therapeutics, School of Medical Sciences, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
- Stoller Biomarker Discovery Centre & Division of Cancer Sciences, Faculty of Biology, Medicine and Health, School of Medical Sciences, The University of Manchester, Manchester, United Kingdom
| | - Garth J. S. Cooper
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, Centre for Advanced Discovery & Experimental Therapeutics, School of Medical Sciences, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
- Faculty of Science, School of Biological Sciences, University of Auckland, Auckland, New Zealand
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5
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Neumann C, Baesler J, Steffen G, Nicolai MM, Zubel T, Aschner M, Bürkle A, Mangerich A, Schwerdtle T, Bornhorst J. The role of poly(ADP-ribose) polymerases in manganese exposed Caenorhabditis elegans. J Trace Elem Med Biol 2020; 57:21-27. [PMID: 31546209 PMCID: PMC6878993 DOI: 10.1016/j.jtemb.2019.09.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 09/05/2019] [Accepted: 09/06/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND AND AIM When exceeding the homeostatic range, manganese (Mn) might cause neurotoxicity, characteristic of the pathophysiology of several neurological diseases. Although the underlying mechanism of its neurotoxicity remains unclear, Mn-induced oxidative stress contributes to disease etiology. DNA damage caused by oxidative stress may further trigger dysregulation of DNA-damage-induced poly(ADP-ribosyl)ation (PARylation), which is of central importance especially for neuronal homeostasis. Accordingly, this study was designed to assess in the genetically traceable in vivo model Caenorhabditis elegans the role of PARylation as well as the consequences of loss of pme-1 or pme-2 (orthologues of PARP1 and PARP2) in Mn-induced toxicity. METHODS A specific and sensitive isotope-dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to quantify PARylation in worms. Next to monitoring the PAR level, pme-1 and pme-2 gene expression as well as Mn-induced oxidative stress was studied in wildtype worms and the pme deletion mutants. RESULTS AND CONCLUSION While Mn failed to induce PARylation in wildtype worms, toxic doses of Mn led to PAR-induction in pme-1-deficient worms, due to an increased gene expression of pme-2 in the pme-1 deletion mutants. However, this effect could not be observed at sub-toxic Mn doses as well as upon longer incubation times. Regarding Mn-induced oxidative stress, the deletion mutants did not show hypersensitivity. Taken together, this study characterizes worms to model PAR inhibition and addresses the consequences for Mn-induced oxidative stress in genetically manipulated worms.
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Affiliation(s)
- Catherine Neumann
- Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany
| | - Jessica Baesler
- Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany; TraceAge - DFG Research Unit FOR 2558, Berlin-Potsdam, Jena, Germany
| | - Gereon Steffen
- Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany
| | - Merle Marie Nicolai
- Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany; Food Chemistry, Faculty of Mathematics and Natural Sciences, University of Wuppertal, Gaußstraße 20, 42119 Wuppertal, Germany
| | - Tabea Zubel
- Department of Biology, University of Konstanz, Universitaetsstraße 10, 78464 Konstanz, Germany
| | - Michael Aschner
- Department of Molecular Pharmacology, Neuroscience, and Pediatrics, Albert Einstein College of Medicine, 1300 Morris Park Avenue, 10461 Bronx, NY, USA
| | - Alexander Bürkle
- Department of Biology, University of Konstanz, Universitaetsstraße 10, 78464 Konstanz, Germany
| | - Aswin Mangerich
- Department of Biology, University of Konstanz, Universitaetsstraße 10, 78464 Konstanz, Germany
| | - Tanja Schwerdtle
- Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany; TraceAge - DFG Research Unit FOR 2558, Berlin-Potsdam, Jena, Germany
| | - Julia Bornhorst
- Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany; TraceAge - DFG Research Unit FOR 2558, Berlin-Potsdam, Jena, Germany; Food Chemistry, Faculty of Mathematics and Natural Sciences, University of Wuppertal, Gaußstraße 20, 42119 Wuppertal, Germany.
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6
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Martins AC, Morcillo P, Ijomone OM, Venkataramani V, Harrison FE, Lee E, Bowman AB, Aschner M. New Insights on the Role of Manganese in Alzheimer's Disease and Parkinson's Disease. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:E3546. [PMID: 31546716 PMCID: PMC6801377 DOI: 10.3390/ijerph16193546] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 12/11/2022]
Abstract
Manganese (Mn) is an essential trace element that is naturally found in the environment and is necessary as a cofactor for many enzymes and is important in several physiological processes that support development, growth, and neuronal function. However, overexposure to Mn may induce neurotoxicity and may contribute to the development of Alzheimer's disease (AD) and Parkinson's disease (PD). The present review aims to provide new insights into the involvement of Mn in the etiology of AD and PD. Here, we discuss the critical role of Mn in the etiology of these disorders and provide a summary of the proposed mechanisms underlying Mn-induced neurodegeneration. In addition, we review some new therapy options for AD and PD related to Mn overload.
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Affiliation(s)
- Airton Cunha Martins
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA (P.M.)
| | - Patricia Morcillo
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA (P.M.)
| | - Omamuyovwi Meashack Ijomone
- Department of Human Anatomy, School of Health and Health Technology, Federal University of Technology Akure, Akure 340252, Nigeria;
| | - Vivek Venkataramani
- Department of Hematology and Medical Oncology and Institute of Pathology, University Medical Center Göttingen (UMG), 37075 Göttingen, Germany;
| | - Fiona Edith Harrison
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA;
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32301, USA;
| | - Aaron Blaine Bowman
- School of Health Sciences, Purdue University, West Lafayette, IN 47907-2051, USA;
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA (P.M.)
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Harischandra DS, Rokad D, Neal ML, Ghaisas S, Manne S, Sarkar S, Panicker N, Zenitsky G, Jin H, Lewis M, Huang X, Anantharam V, Kanthasamy A, Kanthasamy AG. Manganese promotes the aggregation and prion-like cell-to-cell exosomal transmission of α-synuclein. Sci Signal 2019; 12:12/572/eaau4543. [PMID: 30862700 DOI: 10.1126/scisignal.aau4543] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The aggregation of α-synuclein (αSyn) is considered a key pathophysiological feature of certain neurodegenerative disorders, collectively termed synucleinopathies. Given that a prion-like, cell-to-cell transfer of misfolded αSyn has been recognized in the spreading of αSyn pathology in synucleinopathies, we investigated the biological mechanisms underlying the propagation of the disease with respect to environmental neurotoxic stress. Considering the potential role of the divalent metal manganese (Mn2+) in protein aggregation, we characterized its effect on αSyn misfolding and transmission in experimental models of Parkinson's disease. In cultured dopaminergic neuronal cells stably expressing wild-type human αSyn, misfolded αSyn was secreted through exosomes into the extracellular medium upon Mn2+ exposure. These exosomes were endocytosed through caveolae into primary microglial cells, thereby mounting neuroinflammatory responses. Furthermore, Mn2+-elicited exosomes exerted a neurotoxic effect in a human dopaminergic neuronal model (LUHMES cells). Moreover, bimolecular fluorescence complementation (BiFC) analysis revealed that Mn2+ accelerated the cell-to-cell transmission of αSyn, resulting in dopaminergic neurotoxicity in a mouse model of Mn2+ exposure. Welders exposed to Mn2+ had increased misfolded αSyn content in their serum exosomes. Stereotaxically delivering αSyn-containing exosomes, isolated from Mn2+-treated αSyn-expressing cells, into the striatum initiated Parkinsonian-like pathological features in mice. Together, these results indicate that Mn2+ exposure promotes αSyn secretion in exosomal vesicles, which subsequently evokes proinflammatory and neurodegenerative responses in both cell culture and animal models.
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Affiliation(s)
- Dilshan S Harischandra
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Dharmin Rokad
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Matthew L Neal
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Shivani Ghaisas
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Sireesha Manne
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Souvarish Sarkar
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Nikhil Panicker
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Gary Zenitsky
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Huajun Jin
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Mechelle Lewis
- Departments of Neurology and Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA
| | - Xuemei Huang
- Departments of Neurology and Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA
| | - Vellareddy Anantharam
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Arthi Kanthasamy
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA
| | - Anumantha G Kanthasamy
- Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA 50011, USA.
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8
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Chen P, Totten M, Zhang Z, Bucinca H, Erikson K, Santamaría A, Bowma AB, Aschner M. Iron and manganese-related CNS toxicity: mechanisms, diagnosis and treatment. Expert Rev Neurother 2019; 19:243-260. [PMID: 30759034 PMCID: PMC6422746 DOI: 10.1080/14737175.2019.1581608] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 02/08/2019] [Indexed: 12/14/2022]
Abstract
INTRODUCTION Iron (Fe) and manganese (Mn) are essential nutrients for humans. They act as cofactors for a variety of enzymes. In the central nervous system (CNS), these two metals are involved in diverse neurological activities. Dyshomeostasis may interfere with the critical enzymatic activities, hence altering the neurophysiological status and resulting in neurological diseases. Areas covered: In this review, the authors cover the molecular mechanisms of Fe/Mn-induced toxicity and neurological diseases, as well as the diagnosis and potential treatment. Given that both Fe and Mn are abundant in the earth crust, nutritional deficiency is rare. In this review the authors focus on the neurological disorders associated with Mn and Fe overload. Expert commentary: Oxidative stress and mitochondrial dysfunction are the primary molecular mechanism that mediates Fe/Mn-induced neurotoxicity. Although increased Fe or Mn concentrations have been found in brain of patients, it remains controversial whether the elevated metal amounts are the primary cause or secondary consequence of neurological diseases. Currently, treatments are far from satisfactory, although chelation therapy can significantly decrease brain Fe and Mn levels. Studies to determine the primary cause and establish the molecular mechanism of toxicity may help to adapt more comprehensive and satisfactory treatments in the future.
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Affiliation(s)
- Pan Chen
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Melissa Totten
- Department of Nutrition, University of North Carolina Greensboro, Greensboro, NC, USA
| | - Ziyan Zhang
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Hana Bucinca
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Keith Erikson
- Department of Nutrition, University of North Carolina Greensboro, Greensboro, NC, USA
| | - Abel Santamaría
- Laboratory of Excitatory Amino Acids, National Institute of Neurology and Neurosurgery, Mexico, Mexico City, Mexico
| | - Aaron B. Bowma
- School of Health Sciences, Purdue University, West Lafayette, IN, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
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Peres TV, Horning KJ, Bornhorst J, Schwerdtle T, Bowman AB, Aschner M. Small Molecule Modifiers of In Vitro Manganese Transport Alter Toxicity In Vivo. Biol Trace Elem Res 2019; 188:127-134. [PMID: 30267310 PMCID: PMC6438193 DOI: 10.1007/s12011-018-1531-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 09/19/2018] [Indexed: 11/25/2022]
Abstract
Manganese (Mn) is essential for several species and daily requirements are commonly met by an adequate diet. Mn overload may cause motor and psychiatric disturbances and may arise from an impaired or not fully developed excretion system, transporter malfunction and/or exposure to excessive levels of Mn. Therefore, deciphering processes regulating neuronal Mn homeostasis is essential to understand the mechanisms of Mn neurotoxicity. In the present study, we selected two small molecules (with opposing effects on Mn transport) from a previous high throughput screen of 40,167 to test their effects on Mn toxicity parameters in vivo using Caenorhabditis elegans. We pre-exposed worms to VU0063088 and VU0026921 for 30 min followed by co-exposure for 1 h with Mn and evaluated Mn accumulation, dopaminergic (DAergic) degeneration and worm survival. Control worms were exposed to vehicle (DMSO) and saline only. In pdat-1::GFP worms, with GFP labeled DAergic neurons, we observed a decrease of Mn-induced DAergic degeneration in the presence of both small molecules. This effect was also observed in an smf-2 knockout strain. SMF-2 is a regulator of Mn transport in the worms and this strain accumulates higher Mn levels. We did not observe improved survival in the presence of small molecules. Our results suggest that both VU0063088 and VU0026921 may modulate Mn levels in the worms through a mechanism that does not require SMF-2 and induce protection against Mn neurotoxicity.
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Affiliation(s)
- Tanara V Peres
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Kyle J Horning
- Department of Pediatrics, Neurology and Biochemistry, Vanderbilt University Medical Center and Vanderbilt University, Nashville, TN, USA
| | - Julia Bornhorst
- University of Potsdam, Institute of Nutritional Science, Nuthetal, Germany
| | - Tanja Schwerdtle
- University of Potsdam, Institute of Nutritional Science, Nuthetal, Germany
| | - Aaron B Bowman
- Department of Pediatrics, Neurology and Biochemistry, Vanderbilt University Medical Center and Vanderbilt University, Nashville, TN, USA
- School of Health Science, Purdue University, West Lafayette, IN, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA.
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10
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Kornblith ES, Casey SL, Lobdell DT, Colledge MA, Bowler RM. Environmental exposure to manganese in air: Tremor, motor and cognitive symptom profiles. Neurotoxicology 2018; 64:152-158. [PMID: 28965701 PMCID: PMC6260785 DOI: 10.1016/j.neuro.2017.09.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 09/27/2017] [Accepted: 09/27/2017] [Indexed: 01/09/2023]
Abstract
BACKGROUND Excessive exposure to manganese (Mn) may cause parkinsonian-like motor and tremor symptoms and adverse cognitive effects, including problems with executive functioning (EF), resembling those found in later-stage Parkinson's disease (PD). Studies seeking to differentiate PD patients into subgroups with associated cognitive and functional outcomes using motor and tremor symptoms identified tremor-dominant (TD) and non-tremor dominant (NTD) subtypes. It is unclear whether differing patterns of pathophysiology and symptoms exist in Mn neurotoxicity, as they do in PD. METHODS Residents of East Liverpool (n=83) and Marietta, OH (n=99) exposed to chronic (>10years) environmental Mn through industrial pollution were administered neuropsychological measures and a physician-rated scale of movement-disorder symptoms. Two-step cluster analysis was used to group residents based on tremor symptoms, bradykinesia/rigidity symptoms, gait disturbance, and executive function. Cluster membership was validated using modeled air-Mn exposure and a computerized tremor measure. RESULTS Elevated tremor and motor symptoms and executive dysfunction were observed, and TD and NTD symptom clusters were identified. Two additional clusters were also identified: Executive Dysfunction and Normal Functioning. The NTD residents, with elevated levels of gait disturbance and other movement disorder symptoms, did not evidence EF impairment, as predicted. Instead, residents with EF impairment formed their own cluster, and were relatively free of movement disorder symptoms. CONCLUSIONS Results resemble reports in the PD literature with TD and NTD clusters identified, but executive dysfunction did not cluster with NTD symptoms. PD and Mn exposure likely have differing pathophysiology and developmental courses, and therefore different symptom patterns, even when similar symptoms are present.
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Affiliation(s)
- E S Kornblith
- San Francisco VA Medical Center, 4150 Clement Street, San Francisco, CA 94121, United States.
| | - S L Casey
- Alliant International University, San Francisco, CA, United States
| | - D T Lobdell
- US EPA, Research Triangle Park, NC, United States
| | - M A Colledge
- Agency for Toxic Substances and Disease Registry, Chicago, Il, United States
| | - R M Bowler
- San Francisco State University, San Francisco, CA, United States
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11
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Li SJ, Luo YN, Li Y, Chen JW, Mo YH, Yuan ZX, Ou SY, Ou CY, Jiang YM, Deng XF. Sodium para-aminosalicylate protected cultured basal ganglia astrocytes from manganese-induced DNA damages and alteration of amino acid neurotransmitter levels. J Toxicol Sci 2017; 41:573-81. [PMID: 27665767 DOI: 10.2131/jts.41.573] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Sodium para-aminosalicylate (PAS-Na) was first applied successfully in clinical treatment of two manganism patients with good prognosis. However, the mechanism of how PAS-Na protects against Mn-induced neurotoxicity is still elusive. The current study was conducted to explore the effects of PAS-Na on Mn-induced basal ganglia astrocyte injury, and the involvement of amino acid neurotransmitter in vitro. Basal ganglia astrocytes were exposed to 500 μM manganese chloride (MnCl2) for 24 hr, following by 50, 150, or 450 μM PAS-Na treatment for another 24 hr. MnCl2 significantly decreased viability of astrocytes and induced DNA damages via increasing the percentage of tail DNA and Olive tail moment of DNA. Moreover, Mn interrupted amino acid neurotransmitters by decreasing Gln levels and increasing Glu, Gly levels. In contrast, PAS-Na treatment reversed the aforementioned Mn-induced toxic effects on basal ganglia astrocytes. Taken together, our results demonstrated that excessive Mn exposure may induce toxic effects on basal ganglia astrocytes, while PAS-Na could protect basal ganglia astrocytes from Mn-induced neurotoxicity.
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Affiliation(s)
- Shao-Jun Li
- Department of Toxicology, School of Public Health, Guangxi Medical University, China
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12
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Li SJ, Ou CY, He SN, Huang XW, Luo HL, Meng HY, Lu GD, Jiang YM, Vieira Peres T, Luo YN, Deng XF. Sodium p-Aminosalicylic Acid Reverses Sub-Chronic Manganese-Induced Impairments of Spatial Learning and Memory Abilities in Rats, but Fails to Restore γ-Aminobutyric Acid Levels. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2017; 14:ijerph14040400. [PMID: 28394286 PMCID: PMC5409601 DOI: 10.3390/ijerph14040400] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 03/22/2017] [Accepted: 03/23/2017] [Indexed: 02/06/2023]
Abstract
Excessive manganese (Mn) exposure is not only a health risk for occupational workers, but also for the general population. Sodium para-aminosalicylic acid (PAS-Na) has been successfully used in the treatment of manganism, but the involved molecular mechanisms have yet to be determined. The present study aimed to investigate the effects of PAS-Na on sub-chronic Mn exposure-induced impairments of spatial learning and memory, and determine the possible involvements of γ-aminobutyric acid (GABA) metabolism in vivo. Sprague-Dawley male rats received daily intraperitoneal injections MnCl2 (as 6.55 mg/kg Mn body weight, five days per week for 12 weeks), followed by daily subcutaneous injections of 100, 200, or 300 mg/kg PAS-Na for an additional six weeks. Mn exposure significantly impaired spatial learning and memory ability, as noted in the Morris water maze test, and the following PAS-Na treatment successfully restored these adverse effects to levels indistinguishable from controls. Unexpectedly, PAS-Na failed to recover the Mn-induced decrease in the overall GABA levels, although PAS-Na treatment reversed Mn-induced alterations in the enzyme activities directly responsible for the synthesis and degradation of GABA (glutamate decarboxylase and GABA-transaminase, respectively). Moreover, Mn exposure caused an increase of GABA transporter 1 (GAT-1) and decrease of GABA A receptor (GABAA) in transcriptional levels, which could be reverted by the highest dose of 300 mg/kg PAS-Na treatment. In conclusion, the GABA metabolism was interrupted by sub-chronic Mn exposure. However, the PAS-Na treatment mediated protection from sub-chronic Mn exposure-induced neurotoxicity, which may not be dependent on the GABA metabolism.
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Affiliation(s)
- Shao-Jun Li
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China.
| | - Chao-Yan Ou
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China.
- Department of Toxicology, School of Public Health, Guilin Medical University, Guilin 541004, China.
| | - Sheng-Nan He
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China.
| | - Xiao-Wei Huang
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China.
| | - Hai-Lan Luo
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China.
| | - Hao-Yang Meng
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China.
| | - Guo-Dong Lu
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China.
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning 530021, China.
- Key Laboratory of Early Prevention and Treatment for Regional High Frequency Tumor, Ministry of Education, Nanning 530021, China.
| | - Yue-Ming Jiang
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China.
| | - Tanara Vieira Peres
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Forchheimer, 209, 1300 Morris Park Ave, Bronx, NY 10461, USA.
| | - Yi-Ni Luo
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China.
| | - Xiang-Fa Deng
- Department of Anatomy, School of Pre-Clinical Medicine, Guangxi Medical University, Nanning 530021, China.
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13
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"Manganese-induced neurotoxicity: a review of its behavioral consequences and neuroprotective strategies". BMC Pharmacol Toxicol 2016; 17:57. [PMID: 27814772 PMCID: PMC5097420 DOI: 10.1186/s40360-016-0099-0] [Citation(s) in RCA: 198] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 10/19/2016] [Indexed: 01/20/2023] Open
Abstract
Manganese (Mn) is an essential heavy metal. However, Mn’s nutritional aspects are paralleled by its role as a neurotoxicant upon excessive exposure. In this review, we covered recent advances in identifying mechanisms of Mn uptake and its molecular actions in the brain as well as promising neuroprotective strategies. The authors focused on reporting findings regarding Mn transport mechanisms, Mn effects on cholinergic system, behavioral alterations induced by Mn exposure and studies of neuroprotective strategies against Mn intoxication. We report that exposure to Mn may arise from environmental sources, occupational settings, food, total parenteral nutrition (TPN), methcathinone drug abuse or even genetic factors, such as mutation in the transporter SLC30A10. Accumulation of Mn occurs mainly in the basal ganglia and leads to a syndrome called manganism, whose symptoms of cognitive dysfunction and motor impairment resemble Parkinson’s disease (PD). Various neurotransmitter systems may be impaired due to Mn, especially dopaminergic, but also cholinergic and GABAergic. Several proteins have been identified to transport Mn, including divalent metal tranporter-1 (DMT-1), SLC30A10, transferrin and ferroportin and allow its accumulation in the central nervous system. Parallel to identification of Mn neurotoxic properties, neuroprotective strategies have been reported, and these include endogenous antioxidants (for instance, vitamin E), plant extracts (complex mixtures containing polyphenols and non-characterized components), iron chelating agents, precursors of glutathione (GSH), and synthetic compounds that can experimentally afford protection against Mn-induced neurotoxicity.
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14
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Nandipati S, Litvan I. Environmental Exposures and Parkinson's Disease. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:ijerph13090881. [PMID: 27598189 PMCID: PMC5036714 DOI: 10.3390/ijerph13090881] [Citation(s) in RCA: 122] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 08/29/2016] [Accepted: 08/30/2016] [Indexed: 12/21/2022]
Abstract
Parkinson’s disease (PD) affects millions around the world. The Braak hypothesis proposes that in PD a pathologic agent may penetrate the nervous system via the olfactory bulb, gut, or both and spreads throughout the nervous system. The agent is unknown, but several environmental exposures have been associated with PD. Here, we summarize and examine the evidence for such environmental exposures. We completed a comprehensive review of human epidemiologic studies of pesticides, selected industrial compounds, and metals and their association with PD in PubMed and Google Scholar until April 2016. Most studies show that rotenone and paraquat are linked to increased PD risk and PD-like neuropathology. Organochlorines have also been linked to PD in human and laboratory studies. Organophosphates and pyrethroids have limited but suggestive human and animal data linked to PD. Iron has been found to be elevated in PD brain tissue but the pathophysiological link is unclear. PD due to manganese has not been demonstrated, though a parkinsonian syndrome associated with manganese is well-documented. Overall, the evidence linking paraquat, rotenone, and organochlorines with PD appears strong; however, organophosphates, pyrethroids, and polychlorinated biphenyls require further study. The studies related to metals do not support an association with PD.
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Affiliation(s)
- Sirisha Nandipati
- Department of Neurosciences Movement Disorders Center, University of California, San Diego, CA 92093, USA.
| | - Irene Litvan
- Department of Neurosciences Movement Disorders Center, University of California, San Diego, CA 92093, USA.
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15
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Potential Role of Epigenetic Mechanism in Manganese Induced Neurotoxicity. BIOMED RESEARCH INTERNATIONAL 2016; 2016:2548792. [PMID: 27314012 PMCID: PMC4899583 DOI: 10.1155/2016/2548792] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 05/08/2016] [Indexed: 02/07/2023]
Abstract
Manganese is a vital nutrient and is maintained at an optimal level (2.5–5 mg/day) in human body. Chronic exposure to manganese is associated with neurotoxicity and correlated with the development of various neurological disorders such as Parkinson's disease. Oxidative stress mediated apoptotic cell death has been well established mechanism in manganese induced toxicity. Oxidative stress has a potential to alter the epigenetic mechanism of gene regulation. Epigenetic insight of manganese neurotoxicity in context of its correlation with the development of parkinsonism is poorly understood. Parkinson's disease is characterized by the α-synuclein aggregation in the form of Lewy bodies in neuronal cells. Recent findings illustrate that manganese can cause overexpression of α-synuclein. α-Synuclein acts epigenetically via interaction with histone proteins in regulating apoptosis. α-Synuclein also causes global DNA hypomethylation through sequestration of DNA methyltransferase in cytoplasm. An individual genetic difference may also have an influence on epigenetic susceptibility to manganese neurotoxicity and the development of Parkinson's disease. This review presents the current state of findings in relation to role of epigenetic mechanism in manganese induced neurotoxicity, with a special emphasis on the development of Parkinson's disease.
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16
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Manganese-Induced Parkinsonism and Parkinson's Disease: Shared and Distinguishable Features. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:7519-40. [PMID: 26154659 PMCID: PMC4515672 DOI: 10.3390/ijerph120707519] [Citation(s) in RCA: 216] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 12/12/2014] [Accepted: 01/06/2015] [Indexed: 11/30/2022]
Abstract
Manganese (Mn) is an essential trace element necessary for physiological processes that support development, growth and neuronal function. Secondary to elevated exposure or decreased excretion, Mn accumulates in the basal ganglia region of the brain and may cause a parkinsonian-like syndrome, referred to as manganism. The present review discusses the advances made in understanding the essentiality and neurotoxicity of Mn. We review occupational Mn-induced parkinsonism and the dynamic modes of Mn transport in biological systems, as well as the detection and pharmacokinetic modeling of Mn trafficking. In addition, we review some of the shared similarities, pathologic and clinical distinctions between Mn-induced parkinsonism and Parkinson’s disease. Where possible, we review the influence of Mn toxicity on dopamine, gamma aminobutyric acid (GABA), and glutamate neurotransmitter levels and function. We conclude with a survey of the preventive and treatment strategies for manganism and idiopathic Parkinson’s disease (PD).
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17
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Chen P, Chakraborty S, Mukhopadhyay S, Lee E, Paoliello MMB, Bowman AB, Aschner M. Manganese homeostasis in the nervous system. J Neurochem 2015; 134:601-10. [PMID: 25982296 DOI: 10.1111/jnc.13170] [Citation(s) in RCA: 182] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 04/30/2015] [Accepted: 05/04/2015] [Indexed: 12/31/2022]
Abstract
Manganese (Mn) is an essential heavy metal that is naturally found in the environment. Daily intake through dietary sources provides the necessary amount required for several key physiological processes, including antioxidant defense, energy metabolism, immune function and others. However, overexposure from environmental sources can result in a condition known as manganism that features symptomatology similar to Parkinson's disease (PD). This disorder presents with debilitating motor and cognitive deficits that arise from a neurodegenerative process. In order to maintain a balance between its essentiality and neurotoxicity, several mechanisms exist to properly buffer cellular Mn levels. These include transporters involved in Mn uptake, and newly discovered Mn efflux mechanisms. This review will focus on current studies related to mechanisms underlying Mn import and export, primarily the Mn transporters, and their function and roles in Mn-induced neurotoxicity. Though and essential metal, overexposure to manganese may result in neurodegenerative disease analogous to Parkinson's disease. Manganese homeostasis is tightly regulated by transporters, including transmembrane importers (divalent metal transporter 1, transferrin and its receptor, zinc transporters ZIP8 and Zip14, dopamine transporter, calcium channels, choline transporters and citrate transporters) and exporters (ferroportin and SLC30A10), as well as the intracellular trafficking proteins (SPCA1 and ATP12A2). A manganese-specific sensor, GPP130, has been identified, which affords means for monitoring intracellular levels of this metal.
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Affiliation(s)
- Pan Chen
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Sudipta Chakraborty
- Neuroscience Graduate Program, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Somshuvra Mukhopadhyay
- Division of Pharmacology & Toxicology, College of Pharmacy; Institute for Cellular & Molecular Biology; and Institute for Neuroscience, The University of Texas at Austin, Austin, Texas, USA
| | - Eunsook Lee
- Department of Physiology, Meharry Medical College, Nashville, Tennessee, USA
| | - Monica M B Paoliello
- Graduate Program in Public Health, Department of Pathology, Clinical and Toxicological Analysis, Center of Health Science, State University of Londrina, Parana, Brazil
| | - Aaron B Bowman
- Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York, USA.,Neuroscience Graduate Program, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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18
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Neth K, Lucio M, Walker A, Kanawati B, Zorn J, Schmitt-Kopplin P, Michalke B. Diverse Serum Manganese Species Affect Brain Metabolites Depending on Exposure Conditions. Chem Res Toxicol 2015; 28:1434-42. [PMID: 26024413 DOI: 10.1021/acs.chemrestox.5b00104] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Occupational and environmental exposure to increased concentrations of manganese (Mn) can lead to an accumulation of this element in the brain. The consequence is an irreversible damage of dopaminergic neurons leading to a disease called manganism with a clinical presentation similar to the one observed in Parkinson's disease. Human as well as animal studies indicate that Mn is mainly bound to low molecular mass (LMM) compounds such as Mn-citrate when crossing neural barriers. The shift toward LMM compounds might already take place in serum due to elevated Mn concentrations in the body. In this study, we investigated Mn-species pattern in serum in two different animal models by size exclusion chromatography-inductively coupled plasma mass spectrometry (SEC-ICP-MS). A subchronic feeding of rats with elevated levels of Mn led to an increase in LMM compounds, mainly Mn-citrate and Mn bound to amino acids. In addition, a single i.v. injection of Mn showed an increase in Mn-transferrin and Mn bound to amino acids 1 h after injection, while species values were more or less rebalanced 4 days after the injection. Results from Mn-speciation were correlated to the brain metabolome determined by means of electrospray ionization ion cyclotron resonance Fourier transform mass spectrometry (ESI-ICR/FT-MS). The powerful combination of Mn-speciation in serum with metabolomics of the brain underlined the need for Mn-speciation in exposure scenarios instead of the determination of whole Mn concentrations in blood. The progress of Mn-induced neuronal injury might therefore be assessed on the basis of known serum Mn-species.
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Affiliation(s)
| | | | | | | | | | - Philippe Schmitt-Kopplin
- §Technische Universität München, Chair of Analytical Food Chemistry, Alte Akademie 10, D-85354 Freising, Germany
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19
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Lee SJ, Wolff D, Kitko C, Koreth J, Inamoto Y, Jagasia M, Pidala J, Olivieri A, Martin PJ, Przepiorka D, Pusic I, Dignan F, Mitchell SA, Lawitschka A, Jacobsohn D, Hall AM, Flowers MED, Schultz KR, Vogelsang G, Pavletic S. Measuring therapeutic response in chronic graft-versus-host disease. National Institutes of Health consensus development project on criteria for clinical trials in chronic graft-versus-host disease: IV. The 2014 Response Criteria Working Group report. Biol Blood Marrow Transplant 2015; 21:984-99. [PMID: 25796139 PMCID: PMC4744804 DOI: 10.1016/j.bbmt.2015.02.025] [Citation(s) in RCA: 258] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 02/26/2015] [Indexed: 12/17/2022]
Abstract
In 2005, the National Institutes of Health (NIH) Chronic Graft-versus-Host Disease (GVHD) Consensus Response Criteria Working Group recommended several measures to document serial evaluations of chronic GVHD organ involvement. Provisional definitions of complete response, partial response, and progression were proposed for each organ and for overall outcome. Based on publications over the last 9 years, the 2014 Working Group has updated its recommendations for measures and interpretation of organ and overall responses. Major changes include elimination of several clinical parameters from the determination of response, updates to or addition of new organ scales to assess response, and the recognition that progression excludes minimal, clinically insignificant worsening that does not usually warrant a change in therapy. The response definitions have been revised to reflect these changes and are expected to enhance reliability and practical utility of these measures in clinical trials. Clarification is provided about response assessment after the addition of topical or organ-targeted treatment. Ancillary measures are strongly encouraged in clinical trials. Areas suggested for additional research include criteria to identify irreversible organ damage and validation of the modified response criteria, including in the pediatric population.
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Affiliation(s)
- Stephanie J Lee
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Daniel Wolff
- Department of Internal Medicine III, University of Regensburg, Regensburg, Germany
| | - Carrie Kitko
- Department of Pediatrics, University of Michigan, Ann Arbor, Michigan
| | - John Koreth
- Division of Hematologic Malignancies, Dana Farber Cancer Institute, Boston, Massachusetts
| | - Yoshihiro Inamoto
- Division of Hematopoietic Stem Cell Transplantation, National Cancer Center Hospital, Tokyo, Japan
| | - Madan Jagasia
- Division of Hematology-Oncology, Vanderbilt University, Nashville, Tennessee
| | - Joseph Pidala
- Blood and Marrow Transplantation, H. Lee Moffitt Cancer Center, Tampa, Florida
| | - Attilio Olivieri
- Department of Clinical and Molecular Sciences, University of Ancona, Ancona, Italy
| | - Paul J Martin
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Donna Przepiorka
- US Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland
| | - Iskra Pusic
- Department of Medicine, Washington University, St. Louis, Missouri
| | - Fiona Dignan
- Department of Clinical Haematology, University of Manchester, Manchester, United Kingdom
| | - Sandra A Mitchell
- Outcomes Research Branch, National Cancer Institute, Bethesda, Maryland
| | - Anita Lawitschka
- Stem Cell Transplant Unit, St. Anna Children's Hospital, Medical University Vienna, Vienna, Austria
| | - David Jacobsohn
- Division of Blood and Marrow Transplantation, Children's National Health System, Washington, District of Columbia
| | - Anne M Hall
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Mary E D Flowers
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Kirk R Schultz
- BC Children's Hospital, University of British Columbia, Vancouver, Canada
| | | | - Steven Pavletic
- Outcomes Research Branch, National Cancer Institute, Bethesda, Maryland.
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20
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Chen P, Bowman AB, Mukhopadhyay S, Aschner M. SLC30A10: A novel manganese transporter. WORM 2015; 4:e1042648. [PMID: 26430566 DOI: 10.1080/21624054.2015.1042648] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 03/31/2015] [Accepted: 04/10/2015] [Indexed: 10/23/2022]
Abstract
Homozygous mutations in SLC30A10 cause familial parkinsonism associated with manganese (Mn) retention. We recently identified SLC30A10 to be a cell surface-localized Mn efflux transporter and demonstrated that parkinsonism-causing mutations block its intracellular trafficking and efflux function. In C. elegans, SLC30A10 over-expression protected against Mn-induced lethality and dopaminergic neurotoxicity, consistent with results in mammalian systems. Here, we present new data about SLC30A10 function in C. elegans. SLC30A10 expression did not protect worms against ZnSO4toxicity, suggesting that SLC30A10 does not mediate Zn export in C. elegans. Furthermore, while a blast search identified 5 potential SLC30A10 homologs in worms (cdf-1, cdf-2, ttm-1 and toc-1; sequence identity <35%), knock-down of these genes showed a tendency of increased survival after Mn exposure (although only ttm-1 was statistically significant), suggesting that the worm homologs may function differently.
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Affiliation(s)
- Pan Chen
- Department of Molecular Pharmacology; Albert Einstein College of Medicine ; Bronx, NY USA
| | - Aaron B Bowman
- Department of Neurology; Vanderbilt University Medical Center ; Nashville, TN USA
| | - Somshuvra Mukhopadhyay
- Division of Pharmacology & Toxicology; Institute for Cellular and Molecular Biology and Institute for Neuroscience; College of Pharmacy; The University of Texas at Austin ; Austin, TX USA
| | - Michael Aschner
- Department of Molecular Pharmacology; Albert Einstein College of Medicine ; Bronx, NY USA
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21
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Dusek P, Roos PM, Litwin T, Schneider SA, Flaten TP, Aaseth J. The neurotoxicity of iron, copper and manganese in Parkinson's and Wilson's diseases. J Trace Elem Med Biol 2015; 31:193-203. [PMID: 24954801 DOI: 10.1016/j.jtemb.2014.05.007] [Citation(s) in RCA: 155] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 05/05/2014] [Accepted: 05/22/2014] [Indexed: 12/14/2022]
Abstract
Impaired cellular homeostasis of metals, particularly of Cu, Fe and Mn may trigger neurodegeneration through various mechanisms, notably induction of oxidative stress, promotion of α-synuclein aggregation and fibril formation, activation of microglial cells leading to inflammation and impaired production of metalloproteins. In this article we review available studies concerning Fe, Cu and Mn in Parkinson's disease and Wilson's disease. In Parkinson's disease local dysregulation of iron metabolism in the substantia nigra (SN) seems to be related to neurodegeneration with an increase in SN iron concentration, accompanied by decreased SN Cu and ceruloplasmin concentrations and increased free Cu concentrations and decreased ferroxidase activity in the cerebrospinal fluid. Available data in Wilson's disease suggest that substantial increases in CNS Cu concentrations persist for a long time during chelating treatment and that local accumulation of Fe in certain brain nuclei may occur during the course of the disease. Consequences for chelating treatment strategies are discussed.
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Affiliation(s)
- Petr Dusek
- Department of Neurology and Center of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital in Prague, Czech Republic; Institute of Neuroradiology, University Medicine Göttingen, Göttingen, Germany.
| | - Per M Roos
- Department of Neurology, Division of Clinical Neurophysiology, Oslo University Hospital, Oslo, Norway; Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Tomasz Litwin
- 2nd Department of Neurology, Institute of Psychiatry and Neurology, Warsaw, Poland
| | | | - Trond Peder Flaten
- Department of Chemistry, Norwegian University of Science and Technology, Trondheim, Norway
| | - Jan Aaseth
- Department of Medicine, Innlandet Hospital Trust, Kongsvinger Hospital Division, Kongsvinger, Norway
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22
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Bowler RM, Lezak MD. Neuropsychologic evaluation and exposure to neurotoxicants. HANDBOOK OF CLINICAL NEUROLOGY 2015; 131:23-45. [PMID: 26563781 DOI: 10.1016/b978-0-444-62627-1.00003-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The history of neuropsychologic assessment describes the development of a psychometric approach to neuropsychologic measurement, based on the initial clinical/theoretical approach exemplified by pioneers, who also discussed different brain functions and hypotheses for clinical exploration and treatment. Early neuropsychologic assessment practices in the USA arose out of the need to screen, diagnose, and treat World War II veterans who returned with brain injuries. Clinical testing was used to determine treatment and rehabilitation potential. Clinical psychologists had previously developed educational tests to investigate students' abilities and disabilities. Using population studies, primarily in the USA, Canada and Europe, neuropsychologists developed standardized test scores, permitting comparisons of scores based on the normal curve and evolving knowledge of brain/behavior relationships. In clinical interpretations, neuropsychologists use extensive normative data based on cognitive, mood, executive, neurologic, and motor brain functions of groups with different cultural and educational backgrounds and psychiatric illnesses. Large groups of workers can be screened with a brief neuropsychologic screening test battery to assess the psychologic status of personnel. Commonly used tests by domain are described, as well as patterns of acute and chronic neurotoxicant exposures, treatment, and rehabilitation. Future developments will relate imaging studies to neuropsychologic performance.
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Affiliation(s)
- Rosemarie M Bowler
- Department of Psychology, San Francisco State University, San Francisco, CA, USA.
| | - Muriel D Lezak
- Department of Neurology, Oregon Health and Sciences University, Portland, OR, USA
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23
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Younger age at onset of sporadic Parkinson's disease among subjects occupationally exposed to metals and pesticides. Interdiscip Toxicol 2014; 7:123-33. [PMID: 26109889 PMCID: PMC4434105 DOI: 10.2478/intox-2014-0017] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 09/13/2014] [Accepted: 09/14/2014] [Indexed: 12/31/2022] Open
Abstract
An earlier age at onset of Parkinson's disease (PD) has been reported to be associated with occupational exposures to manganese and hydrocarbon solvents suggesting that exposure to neurotoxic chemicals may hasten the progression of idiopathic PD. In this study the role of occupational exposure to metals and pesticides in the progression of idiopathic PD was assessed by looking at age at disease onset. The effects of heritable genetic risk factors, which may also influence age at onset, was minimized by including only sporadic cases of PD with no family history of the disease (n=58). Independent samples Student t-test revealed that subjects with occupational exposure to metals and/or pesticides (n=36) were significantly (p=0.013) younger than unexposed controls (n=22). These subjects were then divided into three groups [high (n=18), low (n=18), and unexposed (n=22)] to ascertain if duration of exposure further influenced age at onset of PD. One-way ANOVA revealed that subjects in the high exposure group were significantly (p=0.0121) younger (mean age: 50.33 years) than unexposed subjects (mean age: 60.45 years). Subjects were also stratified by exposure type (metals vs. pesticides). These results suggest that chronic exposure to metals and pesticides is associated with a younger age at onset of PD among patients with no family history of the disease and that duration of exposure is a factor in the magnitude of this effect.
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24
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Racette BA. Manganism in the 21st century: the Hanninen lecture. Neurotoxicology 2014; 45:201-7. [PMID: 24148923 PMCID: PMC3992192 DOI: 10.1016/j.neuro.2013.09.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 08/27/2013] [Accepted: 09/22/2013] [Indexed: 11/24/2022]
Abstract
Since the original description of the health effects of inhaled occupational manganese (Mn) by Couper in 1837, an extensive literature details the clinical syndrome and pathophysiology of what was thought to be a rare condition. In the last decade, conventional wisdom regarding the clinicopathological effects of Mn has been challenged. Past exposures to Mn were an order of magnitude higher than modern exposures in developed countries; therefore, the clinical syndrome seen in the time of Couper is no longer typical of modern Mn exposed workers. Parkinsonism (rigidity, bradykinesia, rest tremor, and postural instability) is present in 15% of Mn-exposed workers in welding industries, and these parkinsonian signs are associated with reduced health status and quality of life. These parkinsonian signs also overlap considerably with the clinical findings seen in early stages of Parkinson's disease (PD); although, molecular imaging suggests that Mn-exposed workers have dopaminergic dysfunction in a pattern unique from PD. Furthermore, geographic information system studies demonstrate that regions of the US with high industrial Mn emissions have an increased incidence of PD and increased PD associated mortality. This review will contrast historical, descriptive human studies in Mn-exposed subjects with more recent data and will suggest a research agenda for the 21st century.
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Affiliation(s)
- Brad A Racette
- Department of Neurology, Washington University School of Medicine, 660 S. Euclid Avenue, Box 8111, St. Louis, MO 63110, USA; University of the Witwatersrand, School of Public Health, Faculty of Health Sciences, Johannesburg, South Africa.
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25
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Chen P, Parmalee N, Aschner M. Genetic factors and manganese-induced neurotoxicity. Front Genet 2014; 5:265. [PMID: 25136353 PMCID: PMC4120679 DOI: 10.3389/fgene.2014.00265] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 07/18/2014] [Indexed: 11/13/2022] Open
Abstract
Manganese (Mn), is a trace metal required for normal physiological processes in humans. Mn levels are tightly regulated, as high levels of Mn result in accumulation in the brain and cause a neurological disease known as manganism. Manganism shares many similarities with Parkinson’s disease (PD), both at the physiological level and the cellular level. Exposure to high Mn-containing environments increases the risk of developing manganism. Mn is absorbed primarily through the intestine and then released in the blood. Excessive Mn is secreted in the bile and excreted in feces. Mn enters and exits cells through a number of non-specific importers localized on the cell membrane. Mutations in one of the Mn exporters, SLC30A10 (solute carrier family 30, member 10), result in Mn induced toxicity with liver impairments and neurological dysfunction. Four PD genes have been identified in connection to regulation of Mn toxicity, shedding new light on potential links between manganism and PD.
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Affiliation(s)
- Pan Chen
- Department of Molecular Pharmacology, Albert Einstein College of Medicine Bronx, NY, USA
| | - Nancy Parmalee
- Department of Molecular Pharmacology, Albert Einstein College of Medicine Bronx, NY, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine Bronx, NY, USA
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26
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Lu CL, Tang S, Meng ZJ, He YY, Song LY, Liu YP, Ma N, Li XY, Guo SC. Taurine improves the spatial learning and memory ability impaired by sub-chronic manganese exposure. J Biomed Sci 2014; 21:51. [PMID: 24885898 PMCID: PMC4045917 DOI: 10.1186/1423-0127-21-51] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Accepted: 05/18/2014] [Indexed: 11/29/2022] Open
Abstract
Background Excessive manganese exposure induced cognitive deficit. Several lines of evidence have demonstrated that taurine improves cognitive impairment induced by numerous neurotoxins. However, the role of taurine on manganese-induced damages in learning and memory is still elusive. This goal of this study was to investigate the beneficial effect of taurine on learning and memory capacity impairment by manganese exposure in an animal model. Results The escape latency in the Morris Water Maze test was significantly longer in the rats injected with manganese than that in the rats received both taurine and manganese. Similarly, the probe trial showed that the annulus crossings were significantly greater in the taurine plus manganese treated rats than those in the manganese-treated rats. However, the blood level of manganese was not altered by the taurine treatment. Interestingly, the exposure of manganese led to a significant increase in the acetylcholinesterase activity and an evidently decrease in the choline acetyltransferase activity, which were partially restored by the addition of taurine. Additionally, we identified 9 differentially expressed proteins between the rat hippocampus treated by manganese and the control or the manganese plus taurine in the proteomic analysis using the 2-dimensional gel electrophoresis followed by the tandem mass spectrometry (MS/MS). Most of these proteins play a role in energy metabolism, oxidative stress, inflammation, and neuron synapse. Conclusions In summary, taurine restores the activity of AChE and ChAT, which are critical for the regulation of acetylcholine. We have identified seven differentially expressed proteins specifically induced by manganese and two proteins induced by taurine from the rat hippocampus. Our results support that taurine improves the impaired learning and memory ability caused by excessive exposure of manganese.
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Affiliation(s)
| | | | | | | | | | | | | | - Xi-Yi Li
- Department of Food and Nutrition, School of Public Health, Guangxi Medical University, 22 Shuangyong Road, 530021 Nanning, Guangxi, P,R, China.
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27
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Silver DE. Clinical experience with the novel levodopa formulation entacapone + levodopa + carbidopa (Stalevo®). Expert Rev Neurother 2014; 4:589-99. [PMID: 15853578 DOI: 10.1586/14737175.4.4.589] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Levodopa is the main pharmacologic treatment for Parkinson's disease. However, the long-term administration of levodopa is associated with the development of motor complications which can seriously compromise patient function. Increasing evidence indicates that such problems are related to abnormal pulsatile stimulation of striatal dopamine receptors and that treatments providing more continuous stimulation reduce the risk of motor complications. It is possible that administering levodopa with a reversible catechol-O-methyl transferase inhibitor at frequent intervals might reduce the risk of these complications. Stalevo (Orion) combines levodopa, the dopa-decarboxylase inhibitor carbidopa and the catechol-O-methyl transferase inhibitor entacapone in a single tablet. This review provides an overview of the initial clinical experience gained with Stalevo during clinical trials, including several case studies.
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Affiliation(s)
- Dee E Silver
- Coastal Neurological Medical Group, 9850 Genesee Avenue, Suite 740, La Jolla, CA 92037, USA.
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28
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Robison G, Zakharova T, Fu S, Jiang W, Fulper R, Barrea R, Zheng W, Pushkar Y. X-ray fluorescence imaging of the hippocampal formation after manganese exposure. Metallomics 2013; 5:1554-65. [PMID: 23999853 PMCID: PMC3892963 DOI: 10.1039/c3mt00133d] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Manganese (Mn) intoxication results in neurological conditions similar, but not identical, to idiopathic Parkinson's disease. While the mechanism(s) by which Mn exposure leads to neurotoxic effects remains unclear, studies by magnetic resonance imaging demonstrate a high Mn accumulation in the hippocampal formation (HPCf) of the brain. Metal quantification using this method is not possible. Using X-ray fluorescence imaging, we measured the distribution of Mn in the HPCf for a rodent model of chronic Mn exposure and quantitatively compared it with distributions of other biologically relevant metals. We found considerable increases in average Mn concentrations in all analyzed areas and we identified the dentate gyrus (DG) and the cornus ammonis 3 (CA3) layer as areas accumulating the highest Mn content (∼1.2 μg Mn per g tissue). The DG is significantly enriched with iron (Fe), while the CA3 layer has high zinc (Zn) content. Additionally, significant spatial correlations were found for Mn-Zn concentrations across the HPCf substructures and for Mn-Fe concentrations in the DG. Combined results support that at least two mechanisms may be responsible for Mn transport and/or storage in the brain, associated with either Fe or Zn. Subcellular resolution images of metal distribution in cells of the CA3 show diffuse Mn distributions consistent with Mn localization in both the cytoplasm and nucleus. Mn was not increased in localized intracellular Fe or copper accumulations. A consistent Mn-Zn correlation both at the tissue (40 μm × 40 μm) and cellular (0.3 μm × 0.3 μm) levels suggests that a Zn transport/storage mechanism in the HPCf is likely associated with Mn accumulation.
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Affiliation(s)
- Gregory Robison
- Purdue University, Department of Physics, 525 Northwestern Avenue, West Lafayette, IN 47907, USA.
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29
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Park RM. Neurobehavioral deficits and parkinsonism in occupations with manganese exposure: a review of methodological issues in the epidemiological literature. Saf Health Work 2013; 4:123-35. [PMID: 24106642 PMCID: PMC3791085 DOI: 10.1016/j.shaw.2013.07.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 06/19/2013] [Accepted: 07/24/2013] [Indexed: 11/15/2022] Open
Abstract
Exposure to manganese (Mn) is associated with neurobehavioral effects. There is disagreement on whether commonly occurring exposures in welding, ferroalloy, and other industrial processes produce neurologically significant neurobehavioral changes representing parkinsonism. A review of methodological issues in the human epidemiological literature on Mn identified: (1) studies focused on idiopathic Parkinson disease without considering manganism, a parkinsonian syndrome; (2) studies with healthy worker effect bias; (3) studies with problematic statistical modeling; and (4) studies arising from case series derived from litigation. Investigations with adequate study design and exposure assessment revealed consistent neurobehavioral effects and attributable subclinical and clinical signs and symptoms of impairment. Twenty-eight studies show an exposure-response relationship between Mn and neurobehavioral effects, including 11 with continuous exposure metrics and six with three or four levels of contrasted exposure. The effects of sustained low-concentration exposures to Mn are consistent with the manifestations of early manganism, i.e., consistent with parkinsonism. This is compelling evidence that Mn is a neurotoxic chemical and there is good evidence that Mn exposures far below the current US standard of 5.0 mg/m3 are causing impairment.
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Affiliation(s)
- Robert M Park
- National Institute for Occupational Safety and Health, Education and Information Division, Cincinnati, OH, USA
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30
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Stepens A, Groma V, Skuja S, Platkājis A, Aldiņš P, Ekšteina I, Mārtiņsone I, Bricis R, Donaghy M. The outcome of the movement disorder in methcathinone abusers: clinical, MRI and manganesemia changes, and neuropathology. Eur J Neurol 2013; 21:199-205. [PMID: 23678867 DOI: 10.1111/ene.12185] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 03/25/2013] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND PURPOSE There is limited knowledge regarding the long-term outcome of the methcathinone/manganese-induced movement disorder. Our purpose was to define prognosis in intravenous methcathinone abusers affected by this distinctive disorder attributed to manganese (Mn) toxicity. Also, neuropathology from a globus pallidus region biopsy from a former user is reported. METHODS Eighteen methcathinone abusers were categorized as active (five), discontinued (four) or former (nine) users. They were reassessed after a median of 32.5 months (range 3.4-59.6) clinically, on rating scales, and with MRI and blood Mn levels. The biopsy was examined ultrastructurally. RESULTS Overall the group showed a slight tendency to deterioration at follow-up on clinical assessment of motor functioning, especially the active users. No significant change occurred on parkinsonian rating scale reassessment. Significant reduction in Mn levels occurred in former users, and decreased T1-weighted hyperintensity on basal ganglia MRI occurred in 3 of 4 former and 2 of 3 discontinued users, despite lack of clinical improvement. The biopsy consisted of white matter showing decompacted myelin sheaths and frequent abnormalities of mitochondria. CONCLUSIONS No improvement in this Mn-induced movement disorder occurs after cessation of methcathinone abuse despite improvement of Mn blood levels and/or MRI abnormalities. Ultrastructural abnormalities in a former user confirm structural damage to white matter is associated with the disorder. Methcathinone/Mn toxicity is an important, disabling and permanent medical sequel of intravenous drug abuse in the former Soviet Union.
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Affiliation(s)
- A Stepens
- Laboratory for Research in Rehabilitation, Riga Stradins University, Riga, Latvia
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31
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How does an occupational neurologist assess welders and steelworkers for a manganese-induced movement disorder? An international team's experiences in Guanxi, China, part I. J Occup Environ Med 2013; 54:1432-4. [PMID: 23135302 DOI: 10.1097/jom.0b013e318216d0df] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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32
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Santos D, Batoreu MC, Aschner M, Marreilha dos Santos A. Comparison between 5-aminosalicylic acid (5-ASA) and para-aminosalicylic acid (4-PAS) as potential protectors against Mn-induced neurotoxicity. Biol Trace Elem Res 2013; 152:113-6. [PMID: 23315311 PMCID: PMC3594465 DOI: 10.1007/s12011-012-9597-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Accepted: 12/29/2012] [Indexed: 01/12/2023]
Abstract
Manganese (Mn) is an essential metal for biological systems; however, occupational or clinical exposure to high levels of Mn can produce a neurological disorder called manganism. Oxidative stress and neuroinflammation play major roles in the Mn-induced neurodegeneration leading to dysfunction of the basal ganglia. We investigated the toxic effects of MnCl2 in an immortalized rat brain endothelial cell line (RBE4) and the protective effects of the radical scavenging aminosalicylic acids, 5-aminosalicylic acid (5-ASA) and 4-aminosalicylic acid (4-PAS). Mn cytotoxicity was determined with 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) reduction and lactate dehydrogenase (LDH) activity. A significant decrease in MTT reduction concomitant with increased LDH release was noted in RBE4 cells exposed for 24 h to MnCl2 (600 and 800 μM; p < 0.0001). Our results establish that compared to 4-PAS, 5-ASA has greater efficacy in protecting RBE4 cells from Mn-induced neurotoxicity after preexposure to MnCl2 800 μM (p < 0.0001).
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Affiliation(s)
- Dinamene Santos
- I-Med. UL, Department of Toxicology and Food Sciences, Faculty of Pharmacy, University of Lisbon, Lisbon. Portugal
| | - M Camila Batoreu
- I-Med. UL, Department of Toxicology and Food Sciences, Faculty of Pharmacy, University of Lisbon, Lisbon. Portugal
| | - Michael Aschner
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN37232, USA
| | - A.P. Marreilha dos Santos
- I-Med. UL, Department of Toxicology and Food Sciences, Faculty of Pharmacy, University of Lisbon, Lisbon. Portugal
- Corresponding author: , Phone- 351217946400, Fax- 351217946470
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Abstract
Human exposure to neurotoxic metals is a global public health problem. Metals which cause neurological toxicity, such as lead (Pb) and manganese (Mn), are of particular concern due to the long-lasting and possibly irreversible nature of their effects. Pb exposure in childhood can result in cognitive and behavioural deficits in children. These effects are long-lasting and persist into adulthood even after Pb exposure has been reduced or eliminated. While Mn is an essential element of the human diet and serves many cellular functions in the human body, elevated Mn levels can result in a Parkinson's disease (PD)-like syndrome and developmental Mn exposure can adversely affect childhood neurological development. Due to the ubiquitous presence of both metals, reducing human exposure to toxic levels of Mn and Pb remains a world-wide public health challenge. In this review we summarize the toxicokinetics of Pb and Mn, describe their neurotoxic mechanisms, and discuss common themes in their neurotoxicity.
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Affiliation(s)
| | - Tomas R Guilarte
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY 10032, USA.
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34
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Abstract
Manganese (Mn) is an essential trace metal that is pivotal for normal cell function and metabolism. Its homeostasis is tightly regulated; however, the mechanisms of Mn homeostasis are poorly characterized. While a number of proteins such as the divalent metal transporter 1, the transferrin/transferrin receptor complex, the ZIP family metal transporters ZIP-8 and ZIP-14, the secretory pathway calcium ATPases SPCA1 and SPCA2, ATP13A2, and ferroportin have been suggested to play a role in Mn transport, the degree that each of them contributes to Mn homeostasis has still to be determined. The recent discovery of SLC30A10 as a crucial Mn transporter in humans has shed further light on our understanding of Mn transport across the cell. Although essential, Mn is toxic at high concentrations. Mn neurotoxicity has been attributed to impaired dopaminergic (DAergic), glutamatergic and GABAergic transmission, mitochondrial dysfunction, oxidative stress, and neuroinflammation. As a result of preferential accumulation of Mn in the DAergic cells of the basal ganglia, particularly the globus pallidus, Mn toxicity causes extrapyramidal motor dysfunction. Firstly described as "manganism" in miners during the nineteenth century, this movement disorder resembles Parkinson's disease characterized by hypokinesia and postural instability. To date, a variety of acquired causes of brain Mn accumulation can be distinguished from an autosomal recessively inherited disorder of Mn metabolism caused by mutations in the SLC30A10 gene. Both, acquired and inherited hypermanganesemia, lead to Mn deposition in the basal ganglia associated with pathognomonic magnetic resonance imaging appearances of hyperintense basal ganglia on T1-weighted images. Current treatment strategies for Mn toxicity combine chelation therapy to reduce the body Mn load and iron (Fe) supplementation to reduce Mn binding to proteins that interact with both Mn and Fe. This chapter summarizes our current understanding of Mn homeostasis and the mechanisms of Mn toxicity and highlights the clinical disorders associated with Mn neurotoxicity.
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Affiliation(s)
- Karin Tuschl
- Clinical and Molecular Genetics Unit, UCL Institute of Child Health, London, United Kingdom.
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35
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Kim Y, Bowler RM, Abdelouahab N, Harris M, Gocheva V, Roels HA. Motor function in adults of an Ohio community with environmental manganese exposure. Neurotoxicology 2011; 32:606-14. [PMID: 21840336 DOI: 10.1016/j.neuro.2011.07.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 07/27/2011] [Accepted: 07/28/2011] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The objective of the present study was to evaluate motor function in order to assess the effects of long-term, low-level environmental manganese (Mn) exposure in residents of an Ohio community where a large ferro- and silico-Mn smelter has been active for more than 50 years. METHODS One hundred residents from the Mn-exposed Ohio community were evaluated using the Unified Parkinson's Disease Rating Scale (UPDRS), a postural sway test, and a comprehensive questionnaire exploring demographics and general health. The results were compared to those of 90 residents from a demographically similar comparison town in Ohio. Mn exposure was assessed using modeled airborne Mn and blood Mn (Mn-B). The UPDRS was employed to evaluate parkinsonian motor features. Postural sway was measured using a CATSYS 2000 (Danish Product Development). RESULTS No significant difference between the exposed and comparison groups was evident as to Mn-B, demographics or major health outcomes. The risk of abnormal UPDRS performance using "Motor and Bradykinesia" criteria was increased in the Mn-exposed group after adjustment for potential confounders such as the presence of other neurotoxic metals, factors affecting susceptibility to Mn, potential factors influencing motor performance, and other possible demographic confounders. No participant was diagnosed with clinical manganism by neurological examination. After adjustment for various potential confounders, the Mn-exposed group showed significantly higher postural sway scores under eyes-open conditions than the comparison group. CONCLUSIONS Subclinical findings on the UPDRS and postural sway in the Mn-exposed group may possibly reflect early subtle effects of chronic low-level Mn exposure. However, the cross-sectional study design, the small to medium effect sizes, and the little biological plausibility are limiting the possibility of a causal relationship between the environmental Mn-air exposure and the early subclinical neurotoxic effects observed.
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Affiliation(s)
- Yangho Kim
- Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Dong-Gu, Ulsan, South Korea.
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Brna P, Gordon K, Dooley JM, Price V. Manganese toxicity in a child with iron deficiency and polycythemia. J Child Neurol 2011; 26:891-4. [PMID: 21596707 DOI: 10.1177/0883073810393962] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A previously healthy 5-year-old girl presented with pica, emotional lability, and marked gait abnormalities. She had concurrent severe iron deficiency and polycythemia. Her magnetic resonance imaging (MRI) scan showed increased signal in the basal ganglia on T1-weighted images consistent with manganese neurotoxicity. Manganism was subsequently confirmed as her blood manganese levels were extremely elevated. Chelation therapy resulted in improvement in her mobility but she continues to have significant gait impairment. An epidemiological investigation identified well water as the potential source of manganese exposure for our patient, but to date, we have been unable to identify the nature of her neurotoxic susceptibility.
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Affiliation(s)
- Paula Brna
- Division of Neurology, Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada.
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37
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Verhoeven WM, Egger JI, Kuijpers HJ. Manganese and acute paranoid psychosis: a case report. J Med Case Rep 2011; 5:146. [PMID: 21486469 PMCID: PMC3090741 DOI: 10.1186/1752-1947-5-146] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Accepted: 04/12/2011] [Indexed: 11/18/2022] Open
Abstract
Introduction Manganese regulates many enzymes and is essential for normal development and body function. Chronic manganese intoxication has an insidious and progressive course and usually starts with complaints of headache, fatigue, sleep disturbances, irritability and emotional instability. Later, several organ systems may be affected and, due to neurotoxicity, an atypical parkinsonian syndrome may emerge. With regard to neuropsychiatry, an array of symptoms may develop up to 30 years after intoxication, of which gait and speech abnormalities, cognitive and motor slowing, mood changes and hallucinations are the most common. Psychotic phenomena are rarely reported. Case presentation We describe the case of a 49-year-old Caucasian man working as a welder who was referred to our facility for evaluation of acute paranoid psychotic behavior. Our patient's medical history made no mention of any somatic complaints or psychiatric symptoms, and he had been involved in a professional career as a metalworker. On magnetic resonance imaging scanning of his brain, a bilateral hyperdensity of the globus pallidus, suggestive for manganese intoxication, was found. His manganese serum level was 52 to 97 nmol/L (range: 7 to 20 nmol/L). A diagnosis of organic psychotic disorder due to manganese overexposure was made. His psychotic symptoms disappeared within two weeks of treatment with low-dose risperidone. At three months later, serum manganese was decreased to slightly elevated levels and the magnetic resonance imaging T1 signal intensity was reduced. No signs of Parkinsonism were found and a definite diagnosis of manganese-induced apathy syndrome was made. Conclusion Although neuropsychiatric and neurological symptoms caused by (chronic) manganese exposure have been reported frequently in the past, in the present day the disorder is rarely diagnosed. In this report we stress that manganese intoxication can still occur, in our case in a confined-space welder, and may present clinically with a paranoid psychotic state that necessitates a rapid diagnostic procedure in order to avoid the permanent structural brain damage that may occur with chronic exposure.
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Affiliation(s)
- Willem M Verhoeven
- Vincent van Gogh Institute for Psychiatry, Centre of Excellence for Neuropsychiatry, Venray, The Netherlands.
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Verina T, Kiihl SF, Schneider JS, Guilarte TR. Manganese exposure induces microglia activation and dystrophy in the substantia nigra of non-human primates. Neurotoxicology 2011; 32:215-26. [PMID: 21112353 PMCID: PMC3057349 DOI: 10.1016/j.neuro.2010.11.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Revised: 11/18/2010] [Accepted: 11/19/2010] [Indexed: 11/19/2022]
Abstract
Chronic manganese (Mn) exposure produces neurological deficits including a form of parkinsonism that is different from Parkinson's disease (PD). In chronic Mn exposure, dopamine neurons in the substantia nigra (SN) do not degenerate but they appear to be dysfunctional. Further, previous studies have suggested that the substantia nigra pars reticulata (SNr) is affected by Mn. In the present study, we investigated whether chronic Mn exposure induces microglia activation in the substantia nigra pars compacta (SNc) and SNr in Cynomolgus macaques. Animals were exposed to different weekly doses of Mn (3.3-5.0, 5.0-6.7, 8.3-10 mg Mn/kg body weight) and microglia were examined in the substantia nigra using LN3 immunohistochemistry. We observed that in control animals, LN3 labeled microglia were characterized by a resting phenotype. However, in Mn-treated animals, microglia increased in number and displayed reactive changes with increasing Mn exposure. This effect was more prominent in the SNr than in the SNc. In the SNr of animals administered the highest Mn dose, microglia activation was the most advanced and included dystrophic changes. Reactive microglia expressed increased iNOS, L-ferritin, and intracellular ferric iron which were particularly prominent in dystrophic compartments. Our observations indicate that moderate Mn exposure produces structural changes on microglia, which may have significant consequences on their function.
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Affiliation(s)
- Tatyana Verina
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD
| | - Samara F Kiihl
- Department of Biostatistics, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD
| | - Jay S Schneider
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA
| | - Tomás R Guilarte
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD
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Millimolar Mn2+ influences agonist binding to 5-HT1A receptors by inhibiting guanosine nucleotide binding to receptor-coupled G-proteins. Neurotoxicology 2010; 32:25-30. [PMID: 21126535 DOI: 10.1016/j.neuro.2010.11.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Revised: 11/12/2010] [Accepted: 11/23/2010] [Indexed: 12/16/2022]
Abstract
Manganese is an essential trace element but its overexposure causes poisoning (called manganism) that shares several symptoms with Parkinson's disease, but with a mechanism that is still not well understood: in addition to involvement of the dopaminergic system, both serotonergic and peptiergic systems have been implicated. In the present report we have studied the influence of Mn(2+) on 5-HT(1A) receptor signaling complexes in rat brain and found that Mn(2+) in millimolar concentration caused an increase of high-affinity agonist binding to rat hippocampal membranes in comparison with experiments in the presence of Mg(2+), but not in rat cortical membranes and in Sf9 cell membranes expressing 5-HT(1A) receptors and G(i1) heterotrimers. Activation of G proteins with 30μM GTPγS turned all 5-HT(1A) receptors in these preparations into a low-affinity state for agonist binding in the presence of 1mM Mg(2+), but not in the presence of 1mM Mn(2+) in rat hippocampal membranes. However, if 1μM GTPγS was used for G protein activation, a substantial amount of high affinity agonist binding was detected in the presence of Mn(2+) also in cortical membranes and Sf9 cells, but not with Mg(2+) or EDTA. Comparison of the abilities of GDP and GTPγS to modulate high affinity agonist binding to 5-HT(1A) receptors indicated that both nucleotides were almost 10-fold less potent in the presence of MnCl(2) compared to MgCl(2). This means that by inhibiting guanosine nucleotide binding to G proteins in complex with 5-HT(1A) receptors, Mn(2+) acts as an enhancer for agonist binding and signal transduction. As the influence of Mn(2+) resembles the hypersensitivity of dopaminergic system in Parkinsonial models, it can be proposed that at least some symptoms of manganism are connected with a change of signal transduction complex caused by manganese-nucleotide complexes.
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Sikk K, Taba P, Haldre S, Bergquist J, Nyholm D, Askmark H, Danfors T, Sörensen J, Thurfjell L, Raininko R, Eriksson R, Flink R, Färnstrand C, Aquilonius SM. Clinical, neuroimaging and neurophysiological features in addicts with manganese-ephedrone exposure. Acta Neurol Scand 2010; 121:237-43. [PMID: 20028341 DOI: 10.1111/j.1600-0404.2009.01189.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To identify biomarkers supporting the clinical diagnosis of manganism in patients several years after exposure to manganese (Mn). METHODS Neurophysiological examinations, magnetic resonance imaging (MRI), single-photon emission computed tomography and fluorodeoxyglycose (FDG) positron emission tomography were performed in four former ephedrone addicts with extrapyramidal symptoms. RESULTS Peripheral nervous system was not affected. No patients had reduced uptake of (123)I Ioflupane in the striatum. MRI signal intensities were slightly changed in the basal ganglia. All patients showed a widespread, but not uniform, pathological pattern of FDG uptake with changes mainly located to the central part of the brain including the basal ganglia and the surrounding white matter. CONCLUSIONS Presynaptic neurons in the nigrostriatal pathway are intact in Mn-induced parkinsonism after prolonged abstinence from ephedrone. The diagnosis is principally based on clinical signs and the history of drug abuse.
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Dopaminergic neurotoxicity following pulmonary exposure to manganese-containing welding fumes. Arch Toxicol 2010; 84:521-40. [PMID: 20224926 DOI: 10.1007/s00204-010-0525-9] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 02/09/2010] [Indexed: 10/19/2022]
Abstract
The potential for development of Parkinson's disease (PD)-like neurological dysfunction following occupational exposure to aerosolized welding fumes (WF) is an area of emerging concern. Welding consumables contain a complex mixture of metals, including iron (Fe) and manganese (Mn), which are known to be neurotoxic. To determine whether WF exposure poses a neurological risk particularly to the dopaminergic system, we treated Sprague-Dawley rats with WF particulates generated from two different welding processes, gas metal arc-mild steel (GMA-MS; low Mn, less water-soluble) and manual metal arc-hard surfacing (MMA-HS; high Mn, more water-soluble) welding. Following repeated intratracheal instillations (0.5 mg/rat, 1/week x 7 weeks) of GMA-MS or MMA-HS, elemental analysis and various molecular indices of neurotoxicity were measured at 1, 4, 35 or 105 days after last exposure. MMA-HS exposure, in particular, led to increased deposition of Mn in striatum and midbrain. Both fumes also caused loss of tyrosine hydroxylase (TH) protein in the striatum (~20%) and midbrain (~30%) by 1 day post-exposure. While the loss of TH following GMA-MS was transient, a sustained loss (34%) was observed in the midbrain 105 days after cessation of MMA-HS exposure. In addition, both fumes caused persistent down-regulation of dopamine D2 receptor (Drd2; 30-40%) and vesicular monoamine transporter 2 (Vmat2; 30-55%) mRNAs in the midbrain. WF exposure also modulated factors associated with synaptic transmission, oxidative stress, neuroinflammation and gliosis. Collectively, our findings demonstrate that repeated exposure to Mn-containing WF can cause persistent molecular alterations in dopaminergic targets. Whether such perturbations will lead to PD-like neuropathological manifestations remains to be elucidated.
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Nelson M, Huggins T, Licorish R, Carroll MA, Catapane EJ. Effects of p-Aminosalicylic acid on the neurotoxicity of manganese on the dopaminergic innervation of the cilia of the lateral cells of the gill of the bivalve mollusc, Crassostrea virginica. Comp Biochem Physiol C Toxicol Pharmacol 2010; 151:264-70. [PMID: 19944778 PMCID: PMC2794987 DOI: 10.1016/j.cbpc.2009.11.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2009] [Revised: 11/16/2009] [Accepted: 11/17/2009] [Indexed: 11/15/2022]
Abstract
The lateral cilia of the gill of Crassostrea virginica are controlled by a dopaminergic-serotonergic innervation. Dopamine is the neurotransmitter causing cilio-inhibition. High levels of manganese are neurotoxic to people, causing Manganism, a Parkinson-like disease. Clinical interventions for Manganism have not been very successful. Recently, p-Aminosalicylic acid (PAS) was reported as an effective treatment of severe Manganism in humans; however, its mechanism of action is unknown. Previously, we reported that manganese treatments caused disruption of the dopaminergic innervation of gill of C. virginica. Here we compared the effects of manganese on gill innervation in the presence of PAS, EDTA or Acetylsalicylic acid (ASA), and examined whether co-treating animals with PAS could block the deleterious effects of manganese on the oyster's dopaminergic innervation of the gill. Beating rates of the lateral cilia of the gill were measured by stroboscopic microscopy. Pre-treating gill preparations with PAS or EDTA blocked the neurotoxic effects of manganese, while ASA did not. In other experiments, animals exposed to three day treatments with manganese produced a dose dependent impairment of the dopaminergic, cilio-inhibitory system, which was decreased by co-treatment with PAS. The study shows that PAS protects the animal against neurotoxic effects of manganese and the mechanism of action of PAS in alleviating Manganism is more likely related to its chelating abilities than its anti-inflammatory actions.
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Affiliation(s)
- Michael Nelson
- Department of Biology, Medgar Evers College, 1150 Carroll Street, Brooklyn, NY 11225, USA
| | - Turkesha Huggins
- Department of Biology, Medgar Evers College, 1150 Carroll Street, Brooklyn, NY 11225, USA
| | - Roshney Licorish
- Department of Biology, Kingsborough Community College, 2001 Oriental Blvd., Brooklyn, NY 11235, USA
| | - Margaret A. Carroll
- Department of Biology, Medgar Evers College, 1150 Carroll Street, Brooklyn, NY 11225, USA
| | - Edward J. Catapane
- Department of Biology, Medgar Evers College, 1150 Carroll Street, Brooklyn, NY 11225, USA
- Corresponding author. Tel.: +1 718 270 6203. (E.J. Catapane)
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Are there common biochemical and molecular mechanisms controlling manganism and parkisonism. Neuromolecular Med 2009; 11:281-96. [PMID: 19757210 DOI: 10.1007/s12017-009-8088-8] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Accepted: 08/25/2009] [Indexed: 02/08/2023]
Abstract
Over the past several decades there has been considerable progress in our basic knowledge as to the mechanisms and factors regulating Mn toxicity. The disorder known as manganism is associated with the preferential accumulation of Mn in the globus pallidus of the basal ganglia which is generally considered to be the major and initial site of injury. Because the area of the CNS comprising the basal ganglia is very complex and dependent on the precise function and balance of several neurotransmitters, it is not surprising that symptoms of manganism often overlap with that of Parkinson's disease. The fact that neurological symptoms and onset of Mn toxicity are quite broad and can vary unpredictably probably reflects specific genetic variance of the physiological and biochemical makeup within the basal ganglia in any individual. Differences in response to Mn overexposure are, thus, likely due to underlying genetic variability which ultimately presents in deviations in both susceptibility as well as the characteristics of the neurological lesions and symptoms expressed. Although chronic exposure to Mn is not the initial causative agent provoking Parkinsonism, there is evidence suggesting that persistent exposure can predispose an individual to acquire dystonic movements associated with Parkinson's disease. As noted in this review, there appears to be common threads between the two disorders, as mutations in the genes, parkin and ATP13A2, associated with early onset of Parkinsonism, may also predispose an individual to develop Mn toxicity. Mutations in both genes appear to effect transport of Mn into the cell. These genetic difference coupled with additional environmental or nutritional factors must also be considered as contributing to the severity and onset of manganism.
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Curran CP, Park RM, Ho SM, Haynes EN. Incorporating genetics and genomics in risk assessment for inhaled manganese: from data to policy. Neurotoxicology 2009; 30:754-60. [PMID: 19646473 DOI: 10.1016/j.neuro.2009.07.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Revised: 07/10/2009] [Accepted: 07/10/2009] [Indexed: 12/27/2022]
Abstract
Manganese is an essential nutrient, and a healthy human with good liver and kidney function can easily excrete excess dietary manganese. Inhaled manganese is a greater concern, because it bypasses the body's normal homeostatic mechanisms and can accumulate in the brain. Prolonged exposure to high manganese concentrations (>1mg/m(3)) in air leads to a Parkinsonian syndrome known as "manganism." Of greatest concern are recent studies which indicate that neurological and neurobehavioral deficits can occur when workers are exposed to much lower levels (<0.2mg/m(3)) of inhaled manganese in welding fumes. Consequently, researchers at NIOSH are conducting a risk assessment for inhaled manganese. Novel components of this risk assessment include an attempt to quantify the range of inter-individual differences using data generated by the Human Genome Project and experimental work to identify genetically based biomarkers of exposure, disease and susceptibility. The difficulties involved in moving from epidemiological and in vivo data to health-based quantitative risk assessment and ultimately enforceable government standards are discussed.
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Affiliation(s)
- Christine P Curran
- Department of Biological Sciences, Northern Kentucky University, SC342 Nunn Drive, Highland Heights, KY 41099, United States.
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Flynn MR, Susi P. Neurological risks associated with manganese exposure from welding operations--a literature review. Int J Hyg Environ Health 2009; 212:459-69. [PMID: 19181573 DOI: 10.1016/j.ijheh.2008.12.003] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Revised: 12/16/2008] [Accepted: 12/23/2008] [Indexed: 01/09/2023]
Abstract
Exposure to manganese dusts and fumes may cause a clinical neurological syndrome called manganism. Welders are frequently exposed to manganese-containing fumes generated by electric arcs and thermal torches. This paper reviews studies on the association between exposure to such welding fumes and neurological disease. Using the IRSST expert panel criteria, 78 cases of probable/possible, and 19 additional cases of possible occupational manganism were identified in the literature among manganese-exposed workers involved in welding processes. Epidemiological evidence linking welding exposures to Parkinson's disease is still controversial. Although more research is needed to clarify the risks of neurological impairment from welding, control measures including ventilation and adequate respiratory protection, should be implemented to minimize welding fume exposures. The significance of fume transport into the central nervous system via the olfactory nerve, which by-passes the blood-brain barrier, also needs to be assessed.
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Affiliation(s)
- Michael R Flynn
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599-7431, USA.
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Aschner M, Erikson KM, Herrero Hernández E, Hernández EH, Tjalkens R. Manganese and its role in Parkinson's disease: from transport to neuropathology. Neuromolecular Med 2009; 11:252-66. [PMID: 19657747 PMCID: PMC4613768 DOI: 10.1007/s12017-009-8083-0] [Citation(s) in RCA: 216] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Accepted: 07/24/2009] [Indexed: 01/03/2023]
Abstract
The purpose of this review is to highlight recent advances in the neuropathology associated with Mn exposures. We commence with a discussion on occupational manganism and clinical aspects of the disorder. This is followed by novel considerations on Mn transport (see also chapter by Yokel, this volume), advancing new hypotheses on the involvement of several transporters in Mn entry into the brain. This is followed by a brief description of the effects of Mn on neurotransmitter systems that are putative modulators of dopamine (DA) biology (the primary target of Mn neurotoxicity), as well as its effects on mitochondrial dysfunction and disruption of cellular energy metabolism. Next, we discuss inflammatory activation of glia in neuronal injury and how disruption of synaptic transmission and glial-neuronal communication may serve as underlying mechanisms of Mn-induced neurodegeneration commensurate with the cross-talk between glia and neurons. We conclude with a discussion on therapeutic aspects of Mn exposure. Emphasis is directed at treatment modalities and the utility of chelators in attenuating the neurodegenerative sequelae of exposure to Mn. For additional reading on several topics inherent to this review as well as others, the reader may wish to consult Aschner and Dorman (Toxicological Review 25:147-154, 2007) and Bowman et al. (Metals and neurodegeneration, 2009).
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Affiliation(s)
- Michael Aschner
- Departments of Pediatrics and Pharmacology and the Kennedy Center for Research on Human Development, Vanderbilt University Medical Center, 2215-B Garland Avenue, 11425 MRB IV, Nashville, TN, 37232-0414, USA.
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Zheng W, Jiang YM, Zhang Y, Jiang W, Wang X, Cowan DM. Chelation therapy of manganese intoxication with para-aminosalicylic acid (PAS) in Sprague-Dawley rats. Neurotoxicology 2008; 30:240-8. [PMID: 19150464 DOI: 10.1016/j.neuro.2008.12.007] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Revised: 11/19/2008] [Accepted: 12/17/2008] [Indexed: 10/21/2022]
Abstract
Para-aminosalicylic acid (PAS), an FDA-approved anti-tuberculosis drug, has been used successfully in the treatment of severe manganese (Mn)-induced Parkinsonism in humans [Jiang Y-M, Mo X-A, Du FQ, Fu X, Zhu X-Y, Gao H-Y, et al. Effective treatment of manganese-induced occupational Parkinsonism with p-aminosalicylic acid: a case of 17-year follow-up study. J Occup Environ Med 2006;48:644-9]. This study was conducted to explore the capability of PAS in reducing Mn concentrations in body fluids and tissues of Mn-exposed animals. Sprague-Dawley rats received daily intraperitoneally (i.p.) injections of 6mg Mn/kg, 5 days/week for 4 weeks, followed by a daily subcutaneously (s.c.) dose of PAS (100 and 200mg/kg as the PAS-L and PAS-H group, respectively) for another 2, 3 or 6 weeks. Mn exposure significantly increased the concentrations of Mn in plasma, red blood cells (RBC), cerebrospinal fluid (CSF), brain and soft tissues. Following PAS-H treatment for 3 weeks, Mn levels in liver, heart, spleen and pancreas were significantly reduced by 25-33%, while 3 weeks of PAS-L treatment did not show any effect. Further therapy with PAS-H for 6 weeks reduced Mn levels in striatum, thalamus, choroid plexus, hippocampus and frontal cortex by 16-29% (p<0.05). Mn exposure greatly increased iron (Fe) and copper (Cu) concentrations in CSF, brain and liver. Treatment with PAS-H restored Fe and Cu levels comparable with control. These data suggest that PAS likely acts as a chelating agent to mobilize and remove tissue Mn. A high-dose and prolonged PAS treatment appears necessary for its therapeutic effectiveness.
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Affiliation(s)
- Wei Zheng
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA.
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Martin K, Huggins T, King C, Carroll MA, Catapane EJ. The neurotoxic effects of manganese on the dopaminergic innervation of the gill of the bivalve mollusc, Crassostrea virginica. Comp Biochem Physiol C Toxicol Pharmacol 2008; 148:152-9. [PMID: 18547869 PMCID: PMC2533860 DOI: 10.1016/j.cbpc.2008.05.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2008] [Revised: 04/28/2008] [Accepted: 05/02/2008] [Indexed: 10/22/2022]
Abstract
We examined effects of manganese on the nervous system and innervation of lateral cilia of Crassostrea virginica. While essential in trace amounts, tissue manganese accumulation is neurotoxic, inducing Manganism, a Parkinson's-like disease in humans. Lateral cilia of the gill of C. virginica are controlled by a reciprocal serotonergic-dopaminergic innervation from their ganglia. Oysters were incubated 3 days in the presence of up to 1 mM manganese, followed by superfusion of the cerebral ganglia, visceral ganglia or gill with dopamine or serotonin. Beating rates of cilia were measured by stroboscopic microscopy of isolated gill preparations or gill preparations with the ipsilateral cerebral and/or visceral ganglia attached. Acute manganese treatments impaired the dopaminergic, cilio-inhibitory system, while having no effect on the serotonergic, cilio-excitatory system, which is in agreement with the proposed mechanism of manganese toxicity in humans. Manganese treatments also decreased endogenous dopamine levels in the cerebral and visceral ganglia, and gills, but not serotonin levels. We demonstrated that manganese disrupts the animal's dopaminergic system, and also that this preparation can be used to investigate mechanisms that underlie manganese neurotoxicity. It also may serve as a model in pharmacological studies of drugs to treat or prevent Manganism and other dopaminergic cell disorders.
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Affiliation(s)
| | | | | | | | - Edward J. Catapane
- Corresponding author: Department of Biology, Medgar Evers College, 1150 Carroll Street, Brooklyn, NY 11225, USA, Tel: 718.270.6203, fax 718.270.6196, email
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Stepens A, Logina I, Liguts V, Aldins P, Eksteina I, Platkājis A, Mārtinsone I, Tērauds E, Rozentāle B, Donaghy M. A Parkinsonian syndrome in methcathinone users and the role of manganese. N Engl J Med 2008; 358:1009-17. [PMID: 18322282 DOI: 10.1056/nejmoa072488] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND A distinctive extrapyramidal syndrome has been observed in intravenous methcathinone (ephedrone) users in Eastern Europe and Russia. METHODS We studied 23 adults in Latvia who had extrapyramidal symptoms and who had injected methcathinone for a mean (+/-SD) of 6.7+/-5.1 years. The methcathinone was manufactured under home conditions by potassium permanganate oxidation of ephedrine or pseudoephedrine. All patients were positive for hepatitis C virus, and 20 were also positive for the human immunodeficiency virus (HIV). RESULTS The patients reported that the onset of their first neurologic symptoms (gait disturbance in 20 and hypophonia in 3) occurred after a mean of 5.8+/-4.5 years of methcathinone use. At the time of neurologic evaluation, all 23 patients had gait disturbance and difficulty walking backward; 11 patients were falling daily, and 1 of these patients used a wheelchair. Twenty-one patients had hypophonic speech in addition to gait disturbance, and one of these patients was mute. No patient reported decline in cognitive function. T(1)-weighted magnetic resonance imaging (MRI) showed symmetric hyperintensity in the globus pallidus and in the substantia nigra and innominata in all 10 active methcathinone users. Among the 13 former users (2 to 6 years had passed since the last use), lesser degrees of change in the MRI signal were noted. Whole-blood manganese levels (normal level, <209 nmol per liter) averaged 831 nmol per liter (range, 201 to 2102) in the active methcathinone users and 346 nmol per liter (range, 114 to 727) in former users. The neurologic deficits did not resolve after patients discontinued methcathinone use. CONCLUSIONS Our observation of a distinctive extrapyramidal syndrome, changes in the MRI signal in the basal ganglia, and elevated blood manganese levels in methcathinone users suggests that manganese in the methcathinone solution causes a persistent neurologic disorder.
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Affiliation(s)
- Ainārs Stepens
- Department of Neurology, Riga Stradins University, Riga, Latvia
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Meeker JD, Susi P, Flynn MR. Manganese and welding fume exposure and control in construction. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2007; 4:943-951. [PMID: 17963139 DOI: 10.1080/15459620701718867] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Overexposure to welding fume constituents, particularly manganese, is of concern in the construction industry due to the prevalence of welding and the scarcity of engineering controls. The control effectiveness of a commercially available portable local exhaust ventilation (LEV) unit was assessed. It consisted of a portable vacuum and a small bell-shaped hood connected by a flexible 2 inch (50.8 mm) diameter hose, in both experimental and field settings. The experimental testing was done in a semienclosed booth at a pipefitter training facility. Five paired trials of LEV control vs. no control, each approximately 1 hr in duration and conducted during two successive welds of 6 inch (152.4 mm) diameter carbon steel pipe were run in random order. Breathing zone samples were collected outside the welding hood during each trial. In the field scenario, full-shift breathing zone samples were collected from two pipefitters welding carbon steel pipe for a chiller installation on a commercial construction project. Eight days of full-shift sampling were conducted on both workers (n = 16), and the LEV was used by one of the two workers on an alternating basis for 7 of the days. All samples were collected with personal sample pumps calibrated at 2 L/min. Filter cassettes were analyzed for total particulate and manganese concentration by a certified laboratory. In the experimental setting, use of the portable LEV resulted in a 75% reduction in manganese exposure (mean 13 microg/m(3) vs. 51 microg/m(3); p < 0.05) and a 60% reduction in total particulate (mean 0.74 mg/m(3) vs. 1.83 mg/m(3); p < 0.05). In the field setting, LEV use resulted in a 53% reduction in manganese exposure (geometric mean 46 microg/m(3) vs. 97 microg/m(3); p < 0.05) but only a 10% reduction in total particulate (geometric mean 4.5 mg/m(3) vs. 5.0 mg/m(3); p > 0.05). These results demonstrate that LEV use can reduce manganese exposure associated with welding tasks in construction.
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Affiliation(s)
- John D Meeker
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI, USA
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