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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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Baker MG, Lin YS, Simpson CD, Shireman LM, Searles Nielsen S, Racette BA, Seixas N. The reproducibility of urinary ions in manganese exposed workers. J Trace Elem Med Biol 2019; 51:204-211. [PMID: 30466932 PMCID: PMC6291012 DOI: 10.1016/j.jtemb.2018.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 10/30/2018] [Accepted: 11/01/2018] [Indexed: 12/27/2022]
Abstract
PURPOSE Manganese (Mn) is found in environmental and occupational settings, and can cause cognitive and motor impairment. Existing Mn exposure studies have not reached consensus on a valid and reproducible biomarker for Mn exposure. METHODS Previously, global metabolomics data was generated from urine collected in October 2014 using mass spectrometry (MS). Nine ions were found to be different between persons exposed and unexposed to Mn occupationally, though their identity was not able to be determined. Here, we investigated these nine ions in a follow-up set of urine samples taken from the same cohort in January 2015, and in urine samples from a separate Mn-exposed cohort from Wisconsin. We fit an elastic net model fit using the nine ions found in the October 2014 data. RESULTS The elastic net correctly predicted exposure status in 72% of the follow-up samples collected in January 2015, and the area under the curve of the receiver operating characteristic (ROC) curve was 0.8. In the Wisconsin samples, the elastic net performed no better than chance in predicting exposure, possibly due to differences in Mn exposure levels, or unmeasured occupational or environmental co-exposures. CONCLUSIONS This work underscores the importance of taking repeat samples for replication studies when investigating the human urine metabolome, as both within- and between-person variances were observed. Validating and identifying promising results remains a challenge in harnessing global metabolomics for biomarker discovery in occupational cohorts.
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Affiliation(s)
- Marissa G Baker
- Department of Environmental and Occupational Health Sciences, 4225 Roosevelt Way NE Suite 100, University of Washington, Seattle, WA, 98105, USA.
| | - Yvonne S Lin
- Department of Pharmaceutics, 1959 NE Pacific St H-272, University of Washington, Seattle, WA, 98195, USA
| | - Christopher D Simpson
- Department of Environmental and Occupational Health Sciences, 4225 Roosevelt Way NE Suite 100, University of Washington, Seattle, WA, 98105, USA
| | - Laura M Shireman
- Department of Pharmaceutics, 1959 NE Pacific St H-272, University of Washington, Seattle, WA, 98195, USA
| | - Susan Searles Nielsen
- Department of Neurology, 660 S Euclid, Washington University, St. Louis, MO, 63110, USA
| | - Brad A Racette
- Department of Neurology, 660 S Euclid, Washington University, St. Louis, MO, 63110, USA
| | - Noah Seixas
- Department of Environmental and Occupational Health Sciences, 4225 Roosevelt Way NE Suite 100, University of Washington, Seattle, WA, 98105, USA
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Willkommen D, Lucio M, Schmitt-Kopplin P, Gazzaz M, Schroeter M, Sigaroudi A, Michalke B. Species fractionation in a case-control study concerning Parkinson's disease: Cu-amino acids discriminate CSF of PD from controls. J Trace Elem Med Biol 2018; 49:164-170. [PMID: 29472131 DOI: 10.1016/j.jtemb.2018.01.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/02/2018] [Accepted: 01/17/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Parkinson's disease is affecting about 1% of the population above 65 years. Improvements in medicine support prolonged lifetime which increases the total concentration of humans affected by the disease. It is suggested that occupational and environmental exposure to metals like iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn) can influence the risk for Parkinson's disease. These metals play a key role as cofactors in many enzymes and proteins. METHODS In this case-control study, we investigated the Mn-, Fe-, Cu- and Zn-species in cerebrospinal fluid (CSF) by size-exclusion chromatography hyphenated to inductively coupled plasma mass spectrometry (SEC-ICP-MS) and the total concentration of these metals by inductively coupled plasma sector field mass spectrometry (ICP-sf-MS). RESULTS The investigation of total metal concentration and speciation provided only minor changes, but it produced strong significance for a number of ratios. The analysis revealed a strong change in the ratio between total concentration of Fe and the amino acid-fraction of Cu. This could be observed when analyzing both the respective element concentrations of the fraction (which also depends on individual variation of the total element concentration) as well as when being expressed as percentage of total concentration (normalization) which more clearly shows changes of distribution pattern independent of individual variation of total element concentrations. CONCLUSION Speciation analysis, therefore, is a powerful technique to investigate changes in a case-control study where ratios of different species play an important role.
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Affiliation(s)
- Desiree Willkommen
- Helmholtz Zentrum München, Analytical Biogeochemistry, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany.
| | - Marianna Lucio
- Helmholtz Zentrum München, Analytical Biogeochemistry, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Philippe Schmitt-Kopplin
- Helmholtz Zentrum München, Analytical Biogeochemistry, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany; TU München, Lehrstuhl für Analytische Lebensmittelchemie, Wissenschaftszentrum Weihenstephan, Alte Akademie 10, 85354 Freising, Germany
| | - Malaz Gazzaz
- Uniklinik Köln, Institut I für Pharmakologie, Zentrum für Pharmakologie, Gleueler Straße 24, 50931 Köln, Germany
| | - Michael Schroeter
- Uniklinik Köln, Klinik und Poliklinik für Neurologie und Psychiatrie, Kerpener Str. 62, 50924 Köln, Germany
| | - Ali Sigaroudi
- Uniklinik Köln, Institut I für Pharmakologie, Zentrum für Pharmakologie, Gleueler Straße 24, 50931 Köln, Germany; Universitätsspital Zürich, Klinik für Klinische Pharmakologie und Toxikologie, Rämistraße 100, 8091 Zürich, Switzerland
| | - Bernhard Michalke
- Helmholtz Zentrum München, Analytical Biogeochemistry, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
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Follow-up of the manganese-exposed workers healthy cohort (MEWHC) and biobank management from 2011 to 2017 in China. BMC Public Health 2018; 18:944. [PMID: 30068329 PMCID: PMC6090756 DOI: 10.1186/s12889-018-5880-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/24/2018] [Indexed: 12/31/2022] Open
Abstract
Background Long-term excess exposure to environmental manganese (Mn) can lead to multi-system damage, especially in occupational populations. Therefore, we established a manganese-exposed workers healthy cohort (MEWHC), focusing on the systemic health effects related to Mn exposure. Here, we aimed to describe the follow-up activity for the MEWHC study and establish a standardized biological sample bank for the scientific management of high-quality biospecimens and the attached data from 2011 to 2017. Methods Baseline examinations for onsite workers were conducted, and the biobank for the MEWHC was first established in 2011; follow-up examinations occurred four times between July 2012 and November 2017. All questionnaires, clinical data and biological samples were routinely collected during each follow-up activity. Additional workers were recruited in 2016, which further enriched the resources of the biobank. Results A total of 2359 onsite workers and 612 retired workers at a ferromanganese refinery were enrolled in the prospective cohort, and their biological samples were obtained in the preliminary baseline survey and the follow-up investigation, including 2971 blood and urine samples from the cohort. In addition, 1524 hair samples, 1404 nail (toe and finger nails) and 1226 fecal samples were also collected. All specimens were preserved in the biobank, and the data were scientifically managed using a computer system. Conclusions The MEWHC study in China provides an effective way to obtain biological samples such as plasma, DNA, hair and urine for storage in a biobank for further study. The standardized management of various samples is crucial for accessing high-quality biospecimens. Electronic supplementary material The online version of this article (10.1186/s12889-018-5880-0) contains supplementary material, which is available to authorized users.
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Ohgami N, Li X, Yajima I, Oshino R, Ohgami K, Kato Y, Ahsan N, Akhand AA, Kato M. Manganese in toenails is associated with hearing loss at high frequencies in humans. Biomarkers 2018; 23:533-539. [PMID: 29619852 DOI: 10.1080/1354750x.2018.1458153] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE Elevated hearing thresholds from high frequencies are known to be one of the hallmarks of age-related hearing loss. Our recent study showed accumulation of manganese (Mn) in inner ears resulting in acceleration of age-related hearing loss in mice orally exposed to Mn. However, there is no evidence showing an association between Mn in non-invasive biological samples and hearing loss in humans evaluated by pure tone audiometry (PTA). In this study, we evaluated Mn in non-invasive biological samples as a possible biomarker for hearing loss in humans. MATERIALS AND METHODS We determined hearing levels by PTA and Mn levels in toenails, hair and urine with an inductively coupled plasma mass spectrometer (ICP-MS) in 145 healthy subjects in Bangladesh. RESULTS Multivariable analyses showed that Mn levels in toenails, but not in hair and urine samples, were significantly associated with hearing loss at 8 kHz and 12 kHz. Moreover, our experimental study showed a significant correlation between Mn levels in inner ears and nails, but not hair, in mice orally exposed to Mn. CONCLUSIONS The results provide novel evidence that Mn in toenails is a possible biomarker for hearing loss at high frequencies in humans.
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Affiliation(s)
- Nobutaka Ohgami
- a Department of Occupational and Environmental Health , Nagoya University Graduate School of Medicine , Nagoya , Japan.,b Voluntary Body for International Health Care in Universities , Nagoya , Japan
| | - Xiang Li
- a Department of Occupational and Environmental Health , Nagoya University Graduate School of Medicine , Nagoya , Japan
| | - Ichiro Yajima
- a Department of Occupational and Environmental Health , Nagoya University Graduate School of Medicine , Nagoya , Japan.,b Voluntary Body for International Health Care in Universities , Nagoya , Japan
| | - Reina Oshino
- a Department of Occupational and Environmental Health , Nagoya University Graduate School of Medicine , Nagoya , Japan.,b Voluntary Body for International Health Care in Universities , Nagoya , Japan
| | - Kyoko Ohgami
- a Department of Occupational and Environmental Health , Nagoya University Graduate School of Medicine , Nagoya , Japan.,b Voluntary Body for International Health Care in Universities , Nagoya , Japan
| | - Yoko Kato
- a Department of Occupational and Environmental Health , Nagoya University Graduate School of Medicine , Nagoya , Japan.,b Voluntary Body for International Health Care in Universities , Nagoya , Japan
| | - Nazmul Ahsan
- b Voluntary Body for International Health Care in Universities , Nagoya , Japan.,c Department of Genetic Engineering and Biotechnology , University of Dhaka , Dhaka , Bangladesh
| | - Anwarul Azim Akhand
- b Voluntary Body for International Health Care in Universities , Nagoya , Japan.,c Department of Genetic Engineering and Biotechnology , University of Dhaka , Dhaka , Bangladesh
| | - Masashi Kato
- a Department of Occupational and Environmental Health , Nagoya University Graduate School of Medicine , Nagoya , Japan.,b Voluntary Body for International Health Care in Universities , Nagoya , Japan
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Ma RE, Ward EJ, Yeh CL, Snyder S, Long Z, Gokalp Yavuz F, Zauber SE, Dydak U. Thalamic GABA levels and occupational manganese neurotoxicity: Association with exposure levels and brain MRI. Neurotoxicology 2018; 64:30-42. [PMID: 28873337 PMCID: PMC5891096 DOI: 10.1016/j.neuro.2017.08.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 08/30/2017] [Accepted: 08/30/2017] [Indexed: 01/08/2023]
Abstract
Excessive occupational exposure to Manganese (Mn) has been associated with clinical symptoms resembling idiopathic Parkinson's disease (IPD), impairing cognitive and motor functions. Several studies point towards an involvement of the brain neurotransmitter system in Mn intoxication, which is hypothesized to be disturbed prior to onset of symptoms. Edited Magnetic Resonance Spectroscopy (MRS) offers the unique possibility to measure γ-amminobutyric acid (GABA) and other neurometabolites in vivo non-invasively in workers exposed to Mn. In addition, the property of Mn as Magnetic Resonance Imaging (MRI) contrast agent may be used to study Mn deposition in the human brain. In this study, using MRI, MRS, personal air sampling at the working place, work history questionnaires, and neurological assessment (UPDRS-III), the effects of chronic Mn exposure on the thalamic GABAergic system was studied in a group of welders (N=39) with exposure to Mn fumes in a typical occupational setting. Two subgroups of welders with different exposure levels (Low: N=26; mean air Mn=0.13±0.1mg/m3; High: N=13; mean air Mn=0.23±0.18mg/m3), as well as unexposed control workers (N=22, mean air Mn=0.002±0.001mg/m3) were recruited. The group of welders with higher exposure showed a significant increase of thalamic GABA levels by 45% (p<0.01, F(1,33)=9.55), as well as significantly worse performance in general motor function (p<0.01, F(1,33)=11.35). However, welders with lower exposure did not differ from the controls in GABA levels or motor performance. Further, in welders the thalamic GABA levels were best predicted by past-12-months exposure levels and were influenced by the Mn deposition in the substantia nigra and globus pallidus. Importantly, both thalamic GABA levels and motor function displayed a non-linear pattern of response to Mn exposure, suggesting a threshold effect.
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Affiliation(s)
- Ruoyun E Ma
- School of Health Sciences, Purdue University, West Lafayette, IN, USA; Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Eric J Ward
- School of Health Sciences, Purdue University, West Lafayette, IN, USA
| | - Chien-Lin Yeh
- School of Health Sciences, Purdue University, West Lafayette, IN, USA; Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Sandy Snyder
- School of Health Sciences, Purdue University, West Lafayette, IN, USA; Department of Speech, Language and Hearing Sciences, Purdue University, West Lafayette, IN, USA
| | - Zaiyang Long
- School of Health Sciences, Purdue University, West Lafayette, IN, USA; Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - Fulya Gokalp Yavuz
- Department of Statistics, Purdue University, IN, USA; Yildiz Technical University, Istanbul, Turkey
| | - S Elizabeth Zauber
- Department of Neurology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Ulrike Dydak
- School of Health Sciences, Purdue University, West Lafayette, IN, USA; Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN, USA; Department of Speech, Language and Hearing Sciences, Purdue University, West Lafayette, IN, USA.
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Landolfi A, Troisi J, Savanelli MC, Vitale C, Barone P, Amboni M. Bisphenol A glucuronidation in patients with Parkinson’s disease. Neurotoxicology 2017; 63:90-96. [DOI: 10.1016/j.neuro.2017.09.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 09/17/2017] [Accepted: 09/18/2017] [Indexed: 10/18/2022]
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Tarale P, Daiwile AP, Sivanesan S, Stöger R, Bafana A, Naoghare PK, Parmar D, Chakrabarti T, Krishnamurthi K. Manganese exposure: Linking down-regulation of miRNA-7 and miRNA-433 with α-synuclein overexpression and risk of idiopathic Parkinson's disease. Toxicol In Vitro 2017; 46:94-101. [PMID: 28986288 DOI: 10.1016/j.tiv.2017.10.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 08/18/2017] [Accepted: 10/02/2017] [Indexed: 12/16/2022]
Abstract
Manganese is an essential trace element however elevated environmental and occupational exposure to this element has been correlated with neurotoxicity symptoms clinically identical to idiopathic Parkinson's disease. In the present study we chronically exposed human neuroblastoma SH-SY5Y cells to manganese (100μM) and carried out expression profiling of miRNAs known to modulate neuronal differentiation and neurodegeneration. The miRNA PCR array results reveal alterations in expression levels of miRNAs, which have previously been associated with the regulation of synaptic transmission and apoptosis. The expressions of miR-7 and miR-433 significantly reduced upon manganese exposure. By in silico homology analysis we identified SNCA and FGF-20as targets of miR-7 and miR-433. We demonstrate an inverse correlation in expression levels where reduction in these two miRNAs causes increases in SNCA and FGF-20. Transient transfection of SH-SY5Y cells with miR-7 and miR-433 mimics resulted in down regulation of SNCA and FGF-20 mRNA levels. Our study is the first to uncover the potential link between manganese exposure, altered miRNA expression and parkinsonism: manganese exposure causes overexpression of SNCA and FGF-20 by diminishing miR-7 and miR-433 levels. These miRNAs may be considered critical for protection from manganese induced neurotoxic mechanism and hence as potential therapeutic targets.
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Affiliation(s)
- Prashant Tarale
- Environmental Impact and Sustainability Division, CSIR-National Environmental Engineering Research Institute, Nagpur 440020, India; Schools of Biosciences, University of Nottingham, Sutton Bonington Campus, Leicestershire LE12 5RD, UK
| | - Atul P Daiwile
- Environmental Impact and Sustainability Division, CSIR-National Environmental Engineering Research Institute, Nagpur 440020, India
| | - Saravanadevi Sivanesan
- Environmental Impact and Sustainability Division, CSIR-National Environmental Engineering Research Institute, Nagpur 440020, India.
| | - Reinhard Stöger
- Schools of Biosciences, University of Nottingham, Sutton Bonington Campus, Leicestershire LE12 5RD, UK
| | - Amit Bafana
- Environmental Impact and Sustainability Division, CSIR-National Environmental Engineering Research Institute, Nagpur 440020, India
| | - Pravin K Naoghare
- Environmental Impact and Sustainability Division, CSIR-National Environmental Engineering Research Institute, Nagpur 440020, India
| | - Devendra Parmar
- Developmental Toxicology Division, CSIR-Indian Institute of Toxicology Research (IITR), Lucknow-226001, India
| | - Tapan Chakrabarti
- Visvesvaraya National Institute of Technology [VNIT], Nagpur 440010, India
| | - Kannan Krishnamurthi
- Environmental Impact and Sustainability Division, CSIR-National Environmental Engineering Research Institute, Nagpur 440020, India
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Neely MD, Davison CA, Aschner M, Bowman AB. From the Cover: Manganese and Rotenone-Induced Oxidative Stress Signatures Differ in iPSC-Derived Human Dopamine Neurons. Toxicol Sci 2017; 159:366-379. [PMID: 28962525 PMCID: PMC5837701 DOI: 10.1093/toxsci/kfx145] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Parkinson's disease (PD) is the result of complex interactions between genetic and environmental factors. Two chemically distinct environmental stressors relevant to PD are the metal manganese and the pesticide rotenone. Both are thought to exert neurotoxicity at least in part via oxidative stress resulting from impaired mitochondrial activity. Identifying shared mechanism of action may reveal clues towards an understanding of the mechanisms underlying PD pathogenesis. Here we compare the effects of manganese and rotenone in human-induced pluripotent stem cells-derived postmitotic mesencephalic dopamine neurons by assessing several different oxidative stress endpoints. Manganese, but not rotenone caused a concentration and time-dependent increase in intracellular reactive oxygen/nitrogen species measured by quantifying the fluorescence of oxidized chloromethyl 2',7'-dichlorodihydrofluorescein diacetate (DCF) assay. In contrast, rotenone but not manganese caused an increase in cellular isoprostane levels, an indicator of lipid peroxidation. Manganese and rotenone both caused an initial decrease in cellular reduced glutathione; however, glutathione levels remained low in neurons treated with rotenone for 24 h but recovered in manganese-exposed cells. Neurite length, a sensitive indicator of overall neuronal health was adversely affected by rotenone, but not manganese. Thus, our observations suggest that the cellular oxidative stress evoked by these 2 agents is distinct yielding unique oxidative stress signatures across outcome measures. The protective effect of rasagiline, a compound used in the clinic for PD, had negligible impact on any of oxidative stress outcome measures except a subtle significant decrease in manganese-dependent production of reactive oxygen/nitrogen species detected by the DCF assay.
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Affiliation(s)
- M. Diana Neely
- Department of Pediatrics
- Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - Carrie Ann Davison
- Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Aaron B. Bowman
- Department of Pediatrics
- Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee 37232
- Department of Biochemistry, Vanderbilt University, Nashville, Tennessee 37232
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Lee EY, Lewis MM, Mailman RB, Huang X. Distinct neuroimaging features define Parkinson's disease and welding-related neurotoxicity. THE NEUROLOGIST (HYDERABAD, INDIA) 2017; 1:e102. [PMID: 30151503 PMCID: PMC6108171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Affiliation(s)
- Eun-Young Lee
- Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
| | - Mechelle M Lewis
- Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
| | - Richard B Mailman
- Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
| | - Xuemei Huang
- Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Radiology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Neurosurgery, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
- Department of Department of Kinesiology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey PA 17033, USA
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Haynes EN, Sucharew H, Hilbert TJ, Kuhnell P, Spencer A, Newman NC, Burns R, Wright R, Parsons PJ, Dietrich KN. Impact of air manganese on child neurodevelopment in East Liverpool, Ohio. Neurotoxicology 2017; 64:94-102. [PMID: 28888663 DOI: 10.1016/j.neuro.2017.09.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 08/01/2017] [Accepted: 09/01/2017] [Indexed: 01/18/2023]
Abstract
BACKGROUND East Liverpool, Ohio, the site of a hazardous waste incinerator and a manganese (Mn) processor, has had air Mn concentrations exceeding United States Environmental Protection Agency reference levels for over a decade. Save Our County, Inc., a community organization, was formed to address community environmental health concerns related to local industry. Researchers from the University of Cincinnati partnered with Save Our County to determine if air Mn had an impact on the neurocognitive function of children in the community. METHODS Children 7-9 years of age from East Liverpool and its surrounding communities, were enrolled (N=106) in the Communities Actively Researching Exposure Study from between March 2013-June 2014. Blood and hair were analyzed for Mn and lead, and serum was analyzed for cotinine. We used linear regression to assess associations between biological measures and IQ subscale scores. RESULTS Geometric mean blood lead (n=67), blood Mn (n=66), hair Mn (n=98), and serum cotinine (n=69) concentrations were 1.13±1.96μg/dL, 10.06±1.30μg/L, and 360.22±2.17ng/g, 0.76±6.12μg/L respectively. After adjusting for potential confounders, hair Mn was negatively associated with Full Scale IQ. CONCLUSIONS Hair Mn was negatively associated with child IQ scores. Community partners were instrumental in the conception and implementation of this study.
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Affiliation(s)
- Erin N Haynes
- University of Cincinnati, College of Medicine, Department of Environmental Health, 160 Panzeca Way, Cincinnati, OH, 45267, USA.
| | - Heidi Sucharew
- Cincinnati Children's Hospital Medical Center, Division of Biostatistics and Epidemiology, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA.
| | - Timothy J Hilbert
- University of Cincinnati, College of Medicine, Department of Environmental Health, 160 Panzeca Way, Cincinnati, OH, 45267, USA.
| | - Pierce Kuhnell
- Cincinnati Children's Hospital Medical Center, Division of Biostatistics and Epidemiology, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA.
| | | | - Nicholas C Newman
- University of Cincinnati, College of Medicine, Department of Environmental Health, 160 Panzeca Way, Cincinnati, OH, 45267, USA; Cincinnati Children's Hospital Medical Center, Division of General and Community Pediatrics, 3333 Burnet Ave, Cincinnati, OH, 45229, USA.
| | - Roxanne Burns
- Kent State University East Liverpool Campus, 400 E 4th St, East Liverpool, OH, 43920, USA
| | - Robert Wright
- Icahn School of Medicine at Mount Sinai, 1468 Madison Ave, New York, NY, 10029, USA.
| | - Patrick J Parsons
- Wadsworth Center, New York State Department of Health, Albany, NY, 12201-0509, USA; University of Albany, School of Public Health, Department of Environmental Health Sciences, 1400 Washington Ave, Albany, NY, 12222, USA.
| | - Kim N Dietrich
- University of Cincinnati, College of Medicine, Department of Environmental Health, 160 Panzeca Way, Cincinnati, OH, 45267, USA.
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Caggiu E, Paulus K, Galleri G, Arru G, Manetti R, Sechi G, Sechi L. Homologous HSV1 and alpha-synuclein peptides stimulate a T cell response in Parkinson's disease. J Neuroimmunol 2017; 310:26-31. [DOI: 10.1016/j.jneuroim.2017.06.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 06/13/2017] [Indexed: 11/17/2022]
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Zebrafish slc30a10 deficiency revealed a novel compensatory mechanism of Atp2c1 in maintaining manganese homeostasis. PLoS Genet 2017; 13:e1006892. [PMID: 28692648 PMCID: PMC5524415 DOI: 10.1371/journal.pgen.1006892] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 07/24/2017] [Accepted: 06/23/2017] [Indexed: 12/28/2022] Open
Abstract
Recent studies found that mutations in the human SLC30A10 gene, which encodes a manganese (Mn) efflux transporter, are associated with hypermanganesemia with dystonia, polycythemia, and cirrhosis (HMDPC). However, the relationship between Mn metabolism and HMDPC is poorly understood, and no specific treatments are available for this disorder. Here, we generated two zebrafish slc30a10 mutant lines using the CRISPR/Cas9 system. Compared to wild-type animals, mutant adult animals developed significantly higher systemic Mn levels, and Mn accumulated in the brain and liver of mutant embryos in response to exogenous Mn. Interestingly, slc30a10 mutants developed neurological deficits in adulthood, as well as environmental Mn-induced manganism in the embryonic stage; moreover, mutant animals had impaired dopaminergic and GABAergic signaling. Finally, mutant animals developed steatosis, liver fibrosis, and polycythemia accompanied by increased epo expression. This phenotype was rescued partially by EDTA- CaNa2 chelation therapy and iron supplementation. Interestingly, prior to the onset of slc30a10 expression, expressing ATP2C1 (ATPase secretory pathway Ca2+ transporting 1) protected mutant embryos from Mn exposure, suggesting a compensatory role for Atp2c1 in the absence of Slc30a10. Notably, expressing either wild-type or mutant forms of SLC30A10 was sufficient to inhibit the effect of ATP2C1 in response to Mn challenge in both zebrafish embryos and HeLa cells. These findings suggest that either activating ATP2C1 or restoring the Mn-induced trafficking of ATP2C1 can reduce Mn accumulation, providing a possible target for treating HMDPC. Impaired function of the manganese transporter SLC30A10 has been implicated in HMDPC (hypermanganesemia with dystonia, polycythemia, and cirrhosis), an early-onset metabolic disorder clinically characterized by increased systemic Mn levels, neurological impairment, polycythemia, and hepatic injury. No specific treatment is currently available for HMDPC. Moreover, the mechanisms that underlie Mn metabolism are poorly understood, thereby hindering the development of effective treatments. To investigate the physiological processes underlying Mn metabolism and to develop new disease models of HMDPC, we generated two zebrafish slc30a10 mutant lines using the CRISPR/Cas9 system and found that these mutants develop clinical deficits typically associated with HMDPC. Furthermore, we identified a putative compensatory role for ATP2C1 in the absence of SLC30A10 with respect to modulating Mn metabolism. These findings provide a valuable tool for investigating the role of manganese dysregulation in neurological degenerative diseases and which can be used to develop new pharmacological approaches for managing Mn accumulation.
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Criswell SR, Nielsen SS, Warden M, Perlmutter JS, Moerlein SM, Flores HP, Huang J, Sheppard L, Seixas N, Checkoway H, Racette BA. [ 18F]FDOPA positron emission tomography in manganese-exposed workers. Neurotoxicology 2017; 64:43-49. [PMID: 28694016 DOI: 10.1016/j.neuro.2017.07.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 06/20/2017] [Accepted: 07/06/2017] [Indexed: 01/11/2023]
Abstract
Occupational manganese (Mn) exposure is associated with the development of parkinsonism; however, the mechanism of neurotoxicity is unknown. Brain positron emission tomography (PET) imaging provides a non-invasive method of assessing dopamineric neuronal function. 6-[18F]fluoro-L-DOPA (FDOPA) PET reflects in-vivo nigrostriatal function, but results in Mn exposure are conflicting. The objective of this study was to investigate the association between Mn exposure secondary to occupational welding, FDOPA striatal uptake, and clinical parkinsonism as measured by Unified Parkinson Disease Rating Scale motor subscore 3 (UPDRS3) scores. FDOPA PET scans were acquired on 72 subjects (27 Mn-exposed welders, 14 other Mn-exposed workers, and 31 non-exposed subjects). We estimated cumulative welding exposure from detailed work histories, and a movement disorders specialist examined all subjects. Striatal volumes of interest were identified on aligned magnetic resonance imaging (MRI) for each subject. Specific striatal FDOPA uptake was calculated with a graphical analysis method. We used linear regression while adjusting for age to assess the association between welding exposure and FDOPA uptake in the caudate, anterior putamen, and posterior putamen. Compared to the non-exposed subjects, mean caudate FDOPA uptake was 0.0014min-1 (95% confidence interval [CI] 0.0008, 0.0020) lower in Mn-exposed welders and 0.0012min-1 (95% CI 0.0005, 0.0019) lower in other Mn-exposed workers (both p≤0.001). There was no clear dose-response association between caudate FDOPA uptake and Mn exposure or UPDRS3 scores. Mn-exposed welders and workers demonstrated lower caudate FDOPA uptake, indicating pre-synaptic dopaminergic dysfunction in Mn-exposed subjects that was not associated with clinical parkinsonism.
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Affiliation(s)
- Susan R Criswell
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA.
| | - Susan Searles Nielsen
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Mark Warden
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Joel S Perlmutter
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA; Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA; Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA; Program in Physical Therapy, Washington University School of Medicine, St. Louis, MO, USA; Program in Occupational Therapy, Washington University School of Medicine, St. Louis, MO, USA
| | - Stephen M Moerlein
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA; Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
| | - Hubert P Flores
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - John Huang
- Program in Physical Therapy, Washington University School of Medicine, St. Louis, MO, USA
| | - Lianne Sheppard
- Department of Environmental and Occupational Health Sciences, University of Washington, School of Public Health, Seattle, WA, USA; Department of Biostatistics, University of Washington, School of Public Health, Seattle, WA, USA
| | - Noah Seixas
- Department of Environmental and Occupational Health Sciences, University of Washington, School of Public Health, Seattle, WA, USA
| | - Harvey Checkoway
- Department of Family Medicine and Public Health, UC San Diego School of Medicine, La Jolla, CA, USA
| | - Brad A Racette
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA; School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Parktown, South Africa
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Abstract
Although an essential nutrient, manganese (Mn) can be toxic at high doses. There is, however, uncertainty regarding the effects of chronic low-level Mn-exposure. This review provides an overview of Mn-related brain and functional changes based on studies of a cohort of asymptomatic welders who had lower Mn-exposure than in most previous work. In welders with low-level Mn-exposure, we found: 1) Mn may accumulate in the brain in a non-linear fashion: MRI R1 (1/T1) signals significantly increased only after a critical level of exposure was reached (e.g., ≥300 welding hours in the past 90days prior to MRI). Moreover, R1 may be a more sensitive marker to capture short-term dynamic changes in Mn accumulation than the pallidal index [T1-weighted intensity ratio of the globus pallidus vs. frontal white matter], a traditional marker for Mn accumulation; 2) Chronic Mn-exposure may lead to microstructural changes as indicated by lower diffusion tensor fractional anisotropy values in the basal ganglia (BG), especially when welding years exceeded more than 30 years; 3) Mn-related subtle motor dysfunctions can be captured sensitively by synergy metrics (indices for movement stability), whereas traditional fine motor tasks failed to detect any significant differences; and 4) Iron (Fe) also may play a role in welding-related neurotoxicity, especially at low-level Mn-exposure, evidenced by higher R2* values (an estimate for brain Fe accumulation) in the BG. Moreover, higher R2* values were associated with lower phonemic fluency performance. These findings may guide future studies and the development of occupation- and public health-related polices involving Mn-exposure.
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Environmental neurotoxicant manganese regulates exosome-mediated extracellular miRNAs in cell culture model of Parkinson's disease: Relevance to α-synuclein misfolding in metal neurotoxicity. Neurotoxicology 2017; 64:267-277. [PMID: 28450057 DOI: 10.1016/j.neuro.2017.04.007] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/05/2017] [Accepted: 04/18/2017] [Indexed: 12/20/2022]
Abstract
Many chronic neurodegenerative disorders share a common pathogenic mechanism involving the aggregation and deposition of misfolded proteins. Recently, it was shown that these aggregated proteins could be transferred from one cell to another via extracellular nanovesicles called exosomes. Initially thought to be a means of cellular waste removal, exosomes have since been discovered to actively participate in cell-to-cell communication. Importantly, various inflammatory and signaling molecules, as well as small RNAs are selectively packaged in these vesicles. Considering the important role of environmental manganese (Mn) in Parkinson's disease (PD)-like neurological disorders, we characterized the effect of Mn on exosome content and release using an MN9D dopaminergic cell model of PD, which was generated to stably express wild-type human α-synuclein (αSyn). Mn exposure (300μM MnCl2) for 24h induced the release of exosomes into the extracellular media prior to cytotoxicity, as determined by NanoSight particle analysis and electron microscopy. Strikingly, Western blot analysis revealed that Mn treatment in αSyn-expressing cells increases the protein Rab27a, which regulates the release of exosomes from cells. Moreover, next-generation sequencing showed more small RNAs in exosomes isolated from Mn-exposed cells than from control exosomes. Our miRNA profiling analysis led to the discovery of increased expression of certain miRNAs previously shown to regulate key biological pathways, including protein aggregation, autophagy, inflammation and hypoxia. Collectively, our results provide a glimpse of Mn's role in modulating extracellular miRNA content through exosomal release from dopaminergic neuronal cells and thus potentially contributing to progressive neurodegeneration. Further characterization of extracellular miRNAs and their targets will have major impacts on biomarker discovery and translational strategies for environmentally linked neurodegenerative diseases including PD.
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A screening tool to detect clinical manganese neurotoxicity. Neurotoxicology 2017; 64:12-18. [PMID: 28274800 DOI: 10.1016/j.neuro.2017.02.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 02/20/2017] [Indexed: 11/23/2022]
Abstract
Manganese (Mn) over-exposure in occupational settings is associated with basal ganglia toxicity and a movement disorder characterized by parkinsonism (i.e., the signs and symptoms of Parkinson disease). A simple test to help non-neurologists identify workers with clinical Mn neurotoxicity represents an unmet need. In a cohort of Mn-exposed workers from welding worksites, with extensive clinical data, we developed a linear regression model to predict the Unified Parkinson Disease Rating Scale motor subsection part 3 (UPDRS3) score. We primarily considered factors easily obtained in a primary care or occupational medicine clinic, specifically easily assessed signs of parkinsonism and factors likely to be associated with UPDRS3 such as age, timed motor task results, and selected symptoms/conditions. Secondarily we considered other demographic variables and welding exposure. We based the model on 596 examined workers age≤65years and with timed motor task data. We selected the model based on simplicity for clinical application, biologic plausibility, and statistical significance and magnitude of regression coefficients. The model contained age, timed motor task scores for each hand, and indicators of action tremor, speech difficulty, anxiety, depression, loneliness, pain and current cigarette smoking. When we examined how well the model identified workers with clinically significant parkinsonism (UPDRS3≥15) the receiver operating characteristic area under the curve (AUC) was 0.72 (95% confidence interval [CI] 0.67, 0.77). With a cut point that provided 80% sensitivity, specificity was 52%, the positive predictive value in our cohort was 29%, and the negative predictive value was 92%. Using the same cut point for predicted UPDRS3, the AUC was nearly identical for UPDRS3≥10, and was 0.83 (95% CI 0.76, 0.90) for UPDRS3≥20. Since welding exposure data was not required after including its putative effects, this model may help identify workers with clinically significant Mn neurotoxicity in a variety of settings, as a first step in a tiered occupational screening program.
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Wang C, Xu B, Song QF, Deng Y, Liu W, Xu ZF. Manganese exposure disrupts SNARE protein complex-mediated vesicle fusion in primary cultured neurons. ENVIRONMENTAL TOXICOLOGY 2017; 32:705-716. [PMID: 27125645 DOI: 10.1002/tox.22272] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Revised: 03/30/2016] [Accepted: 04/01/2016] [Indexed: 06/05/2023]
Abstract
Overexposure to manganese (Mn) has been known to disrupt neurotransmitter release in the brain. However, the underlying mechanisms of Mn exposure on neurotransmitter vesicle release are still unclear. The current study investigated whether the protein expression and their interaction of SNARE complex associated proteins were the media between Mn exposure and neurotransmitter vesicle fusion disorders. After the neurons were respectively exposed to Mn (0-200 μM) for 0, 6, 12, 18, 24 h, there were different degrees of cell injury in neurons. According to the results, Mn exposures in subsequent experiments were restricted to concentrations of 100 μM for 0, 6, 12, 18, 24 h. Mn was found to down-regulate the expression of SNAP-25 and up-regulate the expression of VAMP-2 in cultured neurons. Moreover, the interaction of Munc 18 and Syntaxin increased significantly in response to Mn treatment for 18-24h, and the interaction of VAMP-2 and Synaptophysin increased first and then decreased. FM1-43-labeled synaptic vesicles also provided evidence that the treatment with Mn resulted in neurotransmitter vesicle fusion increasing first and then decreasing, which was consistent with the 80 kDa protein levels of SNARE complexes. The findings clearly demonstrated that Mn induced the disorders of neurotransmitter vesicle release via disturbing the protein expression and their interaction of SNARE complex associated proteins. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 705-716, 2017.
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Affiliation(s)
- Can Wang
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122, People's Republic of China
| | - Bin Xu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122, People's Republic of China
| | - Qi-Fan Song
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122, People's Republic of China
| | - Yu Deng
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122, People's Republic of China
| | - Wei Liu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122, People's Republic of China
| | - Zhao-Fa Xu
- Department of Environmental Health, School of Public Health, China Medical University, Shenyang, 110122, People's Republic of China
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Al-Lozi A, Nielsen SS, Hershey T, Birke A, Checkoway H, Criswell SR, Racette BA. Cognitive control dysfunction in workers exposed to manganese-containing welding fume. Am J Ind Med 2017; 60:181-188. [PMID: 27862095 DOI: 10.1002/ajim.22675] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2016] [Indexed: 01/31/2023]
Abstract
BACKGROUND Chronic exposure to manganese (Mn) is a health concern in occupations such as welding because of well-established motor effects due to basal ganglia dysfunction. We hypothesized that cognitive control (the ability to monitor, manipulate, and regulate ongoing cognitive demands) would also be affected by chronic Mn exposure. METHODS We examined the relationship between Mn exposure and cognitive control performance in 95 workers with varying intensity and duration (median 15.5 years) of exposure to welding fume. We performed linear regression to assess the association between exposure to Mn-containing welding fume and cognitive control tasks. RESULTS Overall performance was inversely related to intensity of welding exposure (P = 0.009) and was driven by the Two-Back and Letter Number Sequencing tests that assess working memory (both P = 0.02). CONCLUSIONS Occupational exposure to Mn-containing welding fume may be associated with poorer working memory performance, and workers may benefit from practices that reduce exposure intensity. Am. J. Ind. Med. 60:181-188, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Amal Al-Lozi
- Department of Neurology; Washington University in St. Louis School of Medicine; St. Louis Missouri
| | - Susan Searles Nielsen
- Department of Neurology; Washington University in St. Louis School of Medicine; St. Louis Missouri
| | - Tamara Hershey
- Department of Neurology; Washington University in St. Louis School of Medicine; St. Louis Missouri
- Department of Psychiatry; Washington University in St. Louis School of Medicine; St. Louis Missouri
- Department of Radiology; Washington University in St. Louis School of Medicine; St. Louis Missouri
| | - Angela Birke
- Department of Neurology; Washington University in St. Louis School of Medicine; St. Louis Missouri
| | - Harvey Checkoway
- Department of Family Medicine and Public Health; University of California; San Diego California
| | - Susan R. Criswell
- Department of Neurology; Washington University in St. Louis School of Medicine; St. Louis Missouri
| | - Brad A. Racette
- Department of Neurology; Washington University in St. Louis School of Medicine; St. Louis Missouri
- School of Public Health; Faculty of Health Sciences; University of the Witwatersrand; Parktown South Africa
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70
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Nielsen SS, Hu SC, Checkoway H, Negrete M, Palmández P, Bordianu T, Racette BA, Simpson CD. Parkinsonism Signs and Symptoms in Agricultural Pesticide Handlers in Washington State. J Agromedicine 2017; 22:215-221. [PMID: 28418778 PMCID: PMC5533575 DOI: 10.1080/1059924x.2017.1317684] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
OBJECTIVES Examine associations between pesticide exposure and signs or symptoms of parkinsonism. METHODS Prior to the 2014 pesticide spray season, the authors examined 38 active pesticide handlers aged 35 to 65 (median: 43.5) who participated in the State of Washington's cholinesterase monitoring program in the Yakima Valley, where cholinesterase-inhibiting insecticides are applied in fruit orchards. A movement disorder specialist assessed the workers using the Unified Parkinson's Disease Rating Scale (UPDRS) motor subscore 3 (UPDRS3). Participants also self-reported work and medical histories, including the UPDRS activities of daily living subscore 2 (UPDRS2). The authors explored the relation between these scores and lifetime occupational pesticide exposure while accounting for age. RESULTS All participants were Hispanic men born in Mexico who had worked in agriculture for 4 to 43 years (median: 21 years, including 11 years applying pesticides, mostly in the United States). Ten participants (26%) reported difficulty with one or more UPDRS2 activities of daily living (maximum = 2), and nine (24%) had a UPDRS3 >0 (maximum = 10). The most common symptom and sign, respectively, were excess saliva (n = 6) and action tremor (n = 5). UPDRS2 and UPDRS3 scores were unrelated to the number of years applying pesticides, but UPDRS3, especially action tremor, was positively associated with living on or by a farm. CONCLUSIONS Symptoms and signs of parkinsonism were absent to mild in this small sample of active workers who apply cholinesterase-inhibiting insecticides in Washington State, USA. Future studies should be larger and examine older, retired workers with greater cumulative exposure to agricultural pesticides at work and home, including other types of agricultural pesticides.
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Affiliation(s)
- Susan Searles Nielsen
- Washington University School of Medicine, Department of Neurology, St. Louis, MO, USA
| | - Shu-Ching Hu
- University of Washington, School of Medicine, Department of Neurology, Seattle, WA, USA
| | - Harvey Checkoway
- University of California San Diego, Department of Family Medicine and Public Health, La Jolla, California, USA
| | - Maria Negrete
- University of Washington, School of Public Health and Community Medicine, Department of Environmental and Occupational Health Sciences, Seattle, WA, USA
| | - Pablo Palmández
- University of Washington, School of Public Health and Community Medicine, Department of Environmental and Occupational Health Sciences, Seattle, WA, USA
| | - Theresa Bordianu
- University of Washington, School of Public Health and Community Medicine, Department of Environmental and Occupational Health Sciences, Seattle, WA, USA
| | - Brad A. Racette
- Washington University School of Medicine, Department of Neurology, St. Louis, MO, USA
- University of the Witwatersrand, School of Public Health, Parktown, South Africa
| | - Christopher D. Simpson
- University of Washington, School of Public Health and Community Medicine, Department of Environmental and Occupational Health Sciences, Seattle, WA, USA
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71
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Racette BA, Searles Nielsen S, Criswell SR, Sheppard L, Seixas N, Warden MN, Checkoway H. Dose-dependent progression of parkinsonism in manganese-exposed welders. Neurology 2016; 88:344-351. [PMID: 28031394 DOI: 10.1212/wnl.0000000000003533] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 09/12/2016] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To determine whether the parkinsonian phenotype prevalent in welders is progressive, and whether progression is related to degree of exposure to manganese (Mn)-containing welding fume. METHODS This was a trade union-based longitudinal cohort study of 886 American welding-exposed workers with 1,492 examinations by a movement disorders specialist, including 398 workers with 606 follow-up examinations up to 9.9 years after baseline. We performed linear mixed model regression with cumulative Mn exposure as the independent variable and annual change in Unified Parkinson Disease Rating Scale motor subsection part 3 (UPDRS3) as the primary outcome, and subcategories of the UPDRS3 as secondary outcomes. The primary exposure metric was cumulative Mn exposure in mg Mn/m3-year estimated from detailed work histories. RESULTS Progression of parkinsonism increased with cumulative Mn exposure. Specifically, we observed an annual change in UPDRS3 of 0.24 (95% confidence interval 0.10-0.38) for each mg Mn/m3-year of exposure. Exposure was most strongly associated with progression of upper limb bradykinesia, upper and lower limb rigidity, and impairment of speech and facial expression. The association between welding exposure and progression appeared particularly marked in welders who did flux core arc welding in a confined space or workers whose baseline examination was within 5 years of first welding exposure. CONCLUSIONS Exposure to Mn-containing welding fume may cause a dose-dependent progression of parkinsonism, especially upper limb bradykinesia, limb rigidity, and impairment of speech and facial expression.
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Affiliation(s)
- Brad A Racette
- From the Department of Neurology (B.A.R., S.S.N., S.R.C., M.N.W.), Washington University School of Medicine, St. Louis, MO; School of Public Health, Faculty of Health Sciences (B.A.R.), University of the Witwatersrand, Johannesburg, South Africa; Department of Environmental and Occupational Health Sciences (L.S., N.S.), University of Washington, Seattle; and Department of Family Medicine and Public Health (H.C.), University of California, San Diego.
| | - Susan Searles Nielsen
- From the Department of Neurology (B.A.R., S.S.N., S.R.C., M.N.W.), Washington University School of Medicine, St. Louis, MO; School of Public Health, Faculty of Health Sciences (B.A.R.), University of the Witwatersrand, Johannesburg, South Africa; Department of Environmental and Occupational Health Sciences (L.S., N.S.), University of Washington, Seattle; and Department of Family Medicine and Public Health (H.C.), University of California, San Diego
| | - Susan R Criswell
- From the Department of Neurology (B.A.R., S.S.N., S.R.C., M.N.W.), Washington University School of Medicine, St. Louis, MO; School of Public Health, Faculty of Health Sciences (B.A.R.), University of the Witwatersrand, Johannesburg, South Africa; Department of Environmental and Occupational Health Sciences (L.S., N.S.), University of Washington, Seattle; and Department of Family Medicine and Public Health (H.C.), University of California, San Diego
| | - Lianne Sheppard
- From the Department of Neurology (B.A.R., S.S.N., S.R.C., M.N.W.), Washington University School of Medicine, St. Louis, MO; School of Public Health, Faculty of Health Sciences (B.A.R.), University of the Witwatersrand, Johannesburg, South Africa; Department of Environmental and Occupational Health Sciences (L.S., N.S.), University of Washington, Seattle; and Department of Family Medicine and Public Health (H.C.), University of California, San Diego
| | - Noah Seixas
- From the Department of Neurology (B.A.R., S.S.N., S.R.C., M.N.W.), Washington University School of Medicine, St. Louis, MO; School of Public Health, Faculty of Health Sciences (B.A.R.), University of the Witwatersrand, Johannesburg, South Africa; Department of Environmental and Occupational Health Sciences (L.S., N.S.), University of Washington, Seattle; and Department of Family Medicine and Public Health (H.C.), University of California, San Diego
| | - Mark N Warden
- From the Department of Neurology (B.A.R., S.S.N., S.R.C., M.N.W.), Washington University School of Medicine, St. Louis, MO; School of Public Health, Faculty of Health Sciences (B.A.R.), University of the Witwatersrand, Johannesburg, South Africa; Department of Environmental and Occupational Health Sciences (L.S., N.S.), University of Washington, Seattle; and Department of Family Medicine and Public Health (H.C.), University of California, San Diego
| | - Harvey Checkoway
- From the Department of Neurology (B.A.R., S.S.N., S.R.C., M.N.W.), Washington University School of Medicine, St. Louis, MO; School of Public Health, Faculty of Health Sciences (B.A.R.), University of the Witwatersrand, Johannesburg, South Africa; Department of Environmental and Occupational Health Sciences (L.S., N.S.), University of Washington, Seattle; and Department of Family Medicine and Public Health (H.C.), University of California, San Diego
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Tarale P, Sivanesan S, Daiwile AP, Stöger R, Bafana A, Naoghare PK, Parmar D, Chakrabarti T, Kannan K. Global DNA methylation profiling of manganese-exposed human neuroblastoma SH-SY5Y cells reveals epigenetic alterations in Parkinson's disease-associated genes. Arch Toxicol 2016; 91:2629-2641. [PMID: 27913844 DOI: 10.1007/s00204-016-1899-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 11/24/2016] [Indexed: 01/28/2023]
Abstract
Manganese (Mn) is an essential trace element required for optimal functioning of cellular biochemical pathways in the central nervous system. Elevated exposure to Mn through environmental and occupational exposure can cause neurotoxic effects resulting in manganism, a condition with clinical symptoms identical to idiopathic Parkinson's disease. Epigenetics is now recognized as a biological mechanism involved in the etiology of various diseases. Here, we investigated the role of DNA methylation alterations induced by chronic Mn (100 µM) exposure in human neuroblastoma (SH-SY5Y) cells in relevance to Parkinson's disease. A combined analysis of DNA methylation and gene expression data for Parkinson's disease-associated genes was carried out. Whole-genome bisulfite conversion and sequencing indicate epigenetic perturbation of key genes involved in biological processes associated with neuronal cell health. Integration of DNA methylation data with gene expression reveals epigenetic alterations to PINK1, PARK2 and TH genes that play critical roles in the onset of Parkinsonism. The present study suggests that Mn-induced alteration of DNA methylation of PINK1-PARK2 may influence mitochondrial function and promote Parkinsonism. Our findings provide a basis to further explore and validate the epigenetic basis of Mn-induced neurotoxicity .
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Affiliation(s)
- Prashant Tarale
- Environmental Health Division, CSIR - National Environmental Engineering Research Institute (NEERI), Nagpur, 440020, India.,Schools of Biosciences, University of Nottingham, Sutton Bonington Campus, Leicestershire, LE12 5RD, UK
| | - Saravanadevi Sivanesan
- Environmental Health Division, CSIR - National Environmental Engineering Research Institute (NEERI), Nagpur, 440020, India.
| | - Atul P Daiwile
- Environmental Health Division, CSIR - National Environmental Engineering Research Institute (NEERI), Nagpur, 440020, India
| | - Reinhard Stöger
- Schools of Biosciences, University of Nottingham, Sutton Bonington Campus, Leicestershire, LE12 5RD, UK
| | - Amit Bafana
- Environmental Health Division, CSIR - National Environmental Engineering Research Institute (NEERI), Nagpur, 440020, India
| | - Pravin K Naoghare
- Environmental Health Division, CSIR - National Environmental Engineering Research Institute (NEERI), Nagpur, 440020, India
| | - Devendra Parmar
- Developmental Toxicology Division, CSIR-Indian Institute of Toxicology Research (IITR), Lucknow, 226001, India
| | - Tapan Chakrabarti
- Visvesvaraya National Institute of Technology (VNIT), Nagpur, 440010, India
| | - Krishnamurthi Kannan
- Environmental Health Division, CSIR - National Environmental Engineering Research Institute (NEERI), Nagpur, 440020, India
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Freeland-Graves JH, Mousa TY, Kim S. International variability in diet and requirements of manganese: Causes and consequences. J Trace Elem Med Biol 2016; 38:24-32. [PMID: 27264059 DOI: 10.1016/j.jtemb.2016.05.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 05/18/2016] [Accepted: 05/20/2016] [Indexed: 12/14/2022]
Abstract
Manganese (Mn) is an essential trace element that is critical for human health and development. At the turn of the century when diets were based on whole grains, cereals and other traditional foods, Mn intakes (8-9mg/d) were much greater than that prevalent today (2mg/d). As societies have developed, diets have shifted as part of a nutrition transition, to those that are high in processed foods, fat, and sugar. These foods are virtually devoid of Mn. Thus, dietary Mn has declined substantially throughout the world, as confirmed by several wide-scale, total diet studies. International variability in dietary Mn is considerable, due to tremendous diversity in food and culture. In countries where fruit and vegetable intake may be limited, i.e. the United Kingdom, populations may ingest much lower levels of Mn (1.4mg/d) as compared to Asian cultures (4mg/d) which have an abundance of plant foods in their food supply and cuisine. The bioavailability of Mn must be considered, including chemical form, oxidation state, mineral-mineral interactions, presence of dietary components and traditional food processing techniques (milling, germination, malting, fermentation). Manganese toxicity is a public health problem that results from exposure to a naturally high water source or contaminated environment of the soil and/or drinking water. In contrast, inadequate intake is associated with adverse health effects such as diabetes, metabolic syndrome, poor birth outcomes and possibly, cancer. Future studies are recommended to set dietary standards for this mineral in countries that lack recommendations to help achieve optimal health.
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Affiliation(s)
| | - Tamara Y Mousa
- Department of Nutritional Sciences, University of Texas at Austin, USA
| | - Sangyoung Kim
- Department of Nutritional Sciences, University of Texas at Austin, USA
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Ohgami N, Yajima I, Iida M, Li X, Oshino R, Kumasaka MY, Kato M. Manganese-mediated acceleration of age-related hearing loss in mice. Sci Rep 2016; 6:36306. [PMID: 27824154 PMCID: PMC5099889 DOI: 10.1038/srep36306] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 10/13/2016] [Indexed: 12/31/2022] Open
Abstract
Despite the fact that manganese (Mn) is known to be a neurotoxic element relevant to age-related disorders, the risk of oral exposure to Mn for age-related hearing loss remains unclear. In this study, we orally exposed wild-type young adult mice to Mn (Mn-exposed WT-mice) at 1.65 and 16.50 mg/L for 4 weeks. Mn-exposed WT-mice showed acceleration of age-related hearing loss. Mn-exposed WT-mice had neurodegeneration of spiral ganglion neurons (SGNs) with increased number of lipofuscin granules. Mn-exposed WT-mice also had increased hypoxia-inducible factor-1 alpha (Hif-1α) protein with less hydroxylation at proline 564 and decreased c-Ret protein in SGNs. Mn-mediated acceleration of age-related hearing loss involving neurodegeneration of SGNs was rescued in RET-transgenic mice carrying constitutively activated RET. Thus, oral exposure to Mn accelerates age-related hearing loss in mice with Ret-mediated neurodegeneration of SGNs.
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Affiliation(s)
- Nobutaka Ohgami
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Nutritional Health Science Research Center, Chubu University, 1200 Matsumoto, Kasugai, Aichi 487-8501, Japan.,Voluntary Body for International Health Care in Universities, Nagoya, Japan
| | - Ichiro Yajima
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Voluntary Body for International Health Care in Universities, Nagoya, Japan
| | - Machiko Iida
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Xiang Li
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Reina Oshino
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Voluntary Body for International Health Care in Universities, Nagoya, Japan
| | - Mayuko Y Kumasaka
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Masashi Kato
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Voluntary Body for International Health Care in Universities, Nagoya, Japan
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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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Longitudinal T1 relaxation rate (R1) captures changes in short-term Mn exposure in welders. Neurotoxicology 2016; 57:39-44. [PMID: 27567731 DOI: 10.1016/j.neuro.2016.08.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 08/14/2016] [Accepted: 08/22/2016] [Indexed: 11/20/2022]
Abstract
OBJECTIVES We demonstrated recently that the T1 relaxation rate (R1) captured short-term Mn exposure in welders with chronic, relatively low exposure levels in a cross-sectional study. In the current study, we used a longitudinal design to examine whether R1 values reflect the short-term dynamics of Mn exposure. METHODS Twenty-nine welders were evaluated at baseline and 12 months. Occupational questionnaires estimated short-term welding exposure using welding hours in the 90days prior to each study visit (HrsW90). In addition, blood Mn levels, the pallidal index (PI; globus pallidus T1-weighted intensity (T1WI)/frontal white matter T1WI), and R1 values in brain regions of interest (ROIs) were determined as Mn biomarkers at each visit. Associations between changes in estimated welding exposure and changes in purported Mn biomarkers were assessed by Spearman's correlations with adjustment for age and baseline R1, HrsW90, and blood Mn values. RESULTS Changes in welding hours (HrsW90: the short-term welding exposure estimate), was associated significantly with changes in R1 values in the putamen (r=0.541, p=0.005), caudate (R=0.453, p=0.023), globus pallidus (R=0.430, p=0.032), amygdala (R=0.461, p=0.020), and hippocampus (R=0.447, p=0.025), but not with changes in blood Mn levels or the PI. DISCUSSION Changes in R1 values correlated with changes in the short-term welding exposure estimate, but not with more traditional measures of Mn exposure (blood Mn levels or PI). These results suggest that R1 may serve as a useful marker to capture the short-term dynamics in Mn brain accumulation related to welding exposure.
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Ross JA, Shipp EM, Trueblood AB, Bhattacharya A. Ergonomics and Beyond: Understanding How Chemical and Heat Exposures and Physical Exertions at Work Affect Functional Ability, Injury, and Long-Term Health. HUMAN FACTORS 2016; 58:777-795. [PMID: 27125533 PMCID: PMC6894162 DOI: 10.1177/0018720816645457] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 03/12/2016] [Indexed: 06/05/2023]
Abstract
OBJECTIVE To honor Tom Waters's work on emerging occupational health issues, we review the literature on physical along with chemical exposures and their impact on functional outcomes. BACKGROUND Many occupations present the opportunity for exposure to multiple hazardous exposures, including both physical and chemical factors. However, little is known about how these different factors affect functional ability and injury. The goal of this review is to examine the relationships between these exposures, impairment of the neuromuscular and musculoskeletal systems, functional outcomes, and health problems with a focus on acute injury. METHOD Literature was identified using online databases, including PubMed, Ovid Medline, and Google Scholar. References from included articles were searched for additional relevant articles. RESULTS This review documented the limited existing literature that discussed cognitive impairment and functional disorders via neurotoxicity for physical exposures (heat and repetitive loading) and chemical exposures (pesticides, volatile organic compounds [VOCs], and heavy metals). CONCLUSION This review supports that workers are exposed to physical and chemical exposures that are associated with negative health effects, including functional impairment and injury. Innovation in exposure assessment with respect to quantifying the joint exposure to these different exposures is especially needed for developing risk assessment models and, ultimately, preventive measures. APPLICATION Along with physical exposures, chemical exposures need to be considered, alone and in combination, in assessing functional ability and occupationally related injuries.
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Affiliation(s)
- Jennifer A Ross
- Texas A&M University, College StationUniversity of Cincinnati, Ohio
| | - Eva M Shipp
- Texas A&M University, College StationUniversity of Cincinnati, Ohio
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Lee EY, Flynn MR, Du G, Lewis MM, Herring AH, Van Buren E, Van Buren S, Kong L, Mailman RB, Huang X. Editor's Highlight: Lower Fractional Anisotropy in the Globus Pallidus of Asymptomatic Welders, a Marker for Long-Term Welding Exposure. Toxicol Sci 2016; 153:165-73. [PMID: 27466214 DOI: 10.1093/toxsci/kfw116] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
INTRODUCTION Welding fumes contain several metals including manganese (Mn), iron (Fe), and copper (Cu) that at high exposure may co-influence welding-related neurotoxicity. The relationship between brain accumulation of these metals and neuropathology, especially in welders with subclinical exposure levels, is unclear. This study examined the microstructural integrity of basal ganglia (BG) regions in asymptomatic welders using diffusion tensor imaging (DTI). METHODS Subjects with (n = 43) and without (age- and gender-matched controls; n = 31) history of welding were studied. Occupational questionnaires estimated short-term (HrsW; welding hours and E90; cumulative exposure, past 90 days) and long-term (YrsW; total years welding and ELT; cumulative exposure, lifetime) exposure. Whole blood metal levels (Mn, Fe, and Cu) were obtained. Brain MRI pallidal index (PI), R1 (1/T1), and R2* (1/T2*) were measured to estimate Mn and Fe accumulation in BG [caudate, putamen, and globus pallidus (GP)]. DTI was used to assess BG microstructural differences, and related with exposure measurements. RESULTS When compared with controls, welders had significantly lower fractional anisotropy (FA) in the GP. In welders, GP FA values showed non-linear relationships to YrsW, blood Mn, and PI. GP FA decreased after a critical level of YrsW or Mn was reached, whereas it decreased with increasing PI values until plateauing at the highest PI values. GP FA, however, did not show any relationship with short-term exposure measurements (HrsW, E90), blood Cu and Fe, or R(2)* values. CONCLUSION GP FA captured microstructural changes associated with chronic low-level Mn exposure, and may serve as a biomarker for neurotoxicity in asymptomatic welders.
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Affiliation(s)
- Eun-Young Lee
- *Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033
| | - Michael R Flynn
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Guangwei Du
- *Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033
| | - Mechelle M Lewis
- *Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033; Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033
| | - Amy H Herring
- Department of Biostatistics, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Eric Van Buren
- Department of Biostatistics, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Scott Van Buren
- Department of Biostatistics, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Lan Kong
- Department of Public Health Sciences
| | - Richard B Mailman
- *Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033; Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033
| | - Xuemei Huang
- *Department of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033; Department of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033; Department of Radiology; Department of Neurosurgery; Department of Kinesiology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033
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Parmalee NL, Aschner M. Manganese and aging. Neurotoxicology 2016; 56:262-268. [PMID: 27293182 DOI: 10.1016/j.neuro.2016.06.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 06/04/2016] [Accepted: 06/05/2016] [Indexed: 12/11/2022]
Abstract
Manganese (Mn) is an essential metal that is required as a cofactor for many enzymes and is necessary for optimal biological function. Mn is abundant in the earth's crust and is present in soil and well water. Mn is also found in industrial settings, including mining, welding, and battery manufacture. Mn is also present in infant formula, parenteral nutrition, as well as pesticides and gasoline additives. A sufficient amount of Mn is obtained from most diets, and Mn deficiency is exceedingly rare. Excessive exposure to Mn in high doses can result in a condition known as manganism that results in psychological and emotional disturbances and motor symptoms that are reminiscent of Parkinson's disease, including gait disturbance, tremor, rigidity, and bradykinesia. Treatment for manganism is to remove the patient from Mn exposure, though symptoms are generally irreversible. The effects of exposure to Mn at lower doses are less clear. Little work has been done to evaluate the effects of chronic exposure to subclinical levels of Mn, especially in regard to lifelong exposures and the effects on the aging process. Mn is known to have effects on some of the same mechanistic processes that are altered in aging. This review will describe the general effects of Mn exposure and will focus on how Mn may be related to some of the mechanism of aging: neurogenesis, oxidative stress, and microglial activation and inflammation.
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Affiliation(s)
- Nancy L Parmalee
- Albert Einstein College of Medicine, Department of Molecular Pharmacology, 1300 Morris Park Avenue, Bronx, NY, United States.
| | - Michael Aschner
- Albert Einstein College of Medicine, Department of Molecular Pharmacology, 1300 Morris Park Avenue, Bronx, NY, United States.
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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: 35] [Impact Index Per Article: 4.4] [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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Jacobs ML, Dauvilliers Y, St. Louis EK, McCarter SJ, Romenets SR, Pelletier A, Cherif M, Gagnon JF, Postuma RB. Risk Factor Profile in Parkinson’s Disease Subtype with REM Sleep Behavior Disorder. JOURNAL OF PARKINSONS DISEASE 2016; 6:231-7. [DOI: 10.3233/jpd-150725] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Marie L. Jacobs
- Department of Neurology, McGill University, Montreal General Hospital, Montréal, Canada
| | - Yves Dauvilliers
- Reference Center for Narcolepsy, Sleep Unit, Department of Neurology, Hôpital Gui de Chauliac, INSERM U1061, Montpellier, F-34093 Cedex 5 France
| | - Erik K. St. Louis
- Mayo Center for Sleep Medicine, Departments of Medicine and Neurology, Mayo Clinic and Foundation, Rochester, MN, USA
| | - Stuart J. McCarter
- Mayo Center for Sleep Medicine, Departments of Medicine and Neurology, Mayo Clinic and Foundation, Rochester, MN, USA
| | - Silvia Rios Romenets
- Department of Neurology, McGill University, Montreal General Hospital, Montréal, Canada
| | - Amélie Pelletier
- Department of Neurology, McGill University, Montreal General Hospital, Montréal, Canada
- Centre d’Études Avancées en Médecine du Sommeil, Hôpital du Sacré-Coeur de Montréal, Montréal, Canada
| | - Mahmoud Cherif
- Department of Neurology, Hôpital Gui de Chauliac, INSERM U1061, Montpellier, F-34093 Cedex 5 France
| | - Jean-François Gagnon
- Centre d’Études Avancées en Médecine du Sommeil, Hôpital du Sacré-Coeur de Montréal, Montréal, Canada
- Département de psychologie, Université du Québec à Montréal, Montréal, QC, Canada
| | - Ronald B. Postuma
- Department of Neurology, McGill University, Montreal General Hospital, Montréal, Canada
- Centre d’Études Avancées en Médecine du Sommeil, Hôpital du Sacré-Coeur de Montréal, Montréal, Canada
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Omics for prediction of environmental health effects: Blood leukocyte-based cross-omic profiling reliably predicts diseases associated with tobacco smoking. Sci Rep 2016; 6:20544. [PMID: 26837704 PMCID: PMC4738297 DOI: 10.1038/srep20544] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 01/06/2016] [Indexed: 01/13/2023] Open
Abstract
The utility of blood-based omic profiles for linking environmental exposures to their potential health effects was evaluated in 649 individuals, drawn from the general population, in relation to tobacco smoking, an exposure with well-characterised health effects. Using disease connectivity analysis, we found that the combination of smoking-modified, genome-wide gene (including miRNA) expression and DNA methylation profiles predicts with remarkable reliability most diseases and conditions independently known to be causally associated with smoking (indicative estimates of sensitivity and positive predictive value 94% and 84%, respectively). Bioinformatics analysis reveals the importance of a small number of smoking-modified, master-regulatory genes and suggest a central role for altered ubiquitination. The smoking-induced gene expression profiles overlap significantly with profiles present in blood cells of patients with lung cancer or coronary heart disease, diseases strongly associated with tobacco smoking. These results provide proof-of-principle support to the suggestion that omic profiling in peripheral blood has the potential of identifying early, disease-related perturbations caused by toxic exposures and may be a useful tool in hazard and risk assessment.
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Wahlberg K, Kippler M, Alhamdow A, Rahman SM, Smith DR, Vahter M, Lucchini RG, Broberg K. Common Polymorphisms in the Solute Carrier SLC30A10 are Associated With Blood Manganese and Neurological Function. Toxicol Sci 2015; 149:473-83. [PMID: 26628504 PMCID: PMC4725612 DOI: 10.1093/toxsci/kfv252] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Manganese (Mn) is an essential nutrient in humans, but excessive exposure to Mn may cause neurotoxicity. Despite homeostatic regulation, Mn concentrations in blood vary considerably among individuals. We evaluated if common single-nucleotide polymorphisms (SNPs) in SLC30A10, which likely encodes an Mn transporter, influence blood Mn concentrations and neurological function. We measured blood Mn concentrations by ICP-MS or atomic absorption spectroscopy and genotyped 2 SLC30A10 non-coding SNPs (rs2275707 and rs12064812) by TaqMan PCR in cohorts from Bangladesh (N = 406), the Argentinean Andes (N = 198), and Italy (N = 238). We also measured SLC30A10 expression in whole blood by TaqMan PCR in a sub-group (N = 101) from the Andean cohort, and neurological parameters (sway velocity and finger-tapping speed) in the Italian cohort. The rs2275707 variant allele was associated with increased Mn concentrations in the Andes (8%, P = .027) and Italy (10.6%, P = .012), but not as clear in Bangladesh (3.4%, P = .21; linear regression analysis adjusted for age, gender, and plasma ferritin). This allele was also associated with increased sway velocity (15%, P = .033; adjusted for age and sex) and reduced SLC30A10 expression (−24.6%, P = .029). In contrast, the rs12064812 variant homozygous genotype was associated with reduced Mn concentrations, particularly in the Italian cohort (−18.4%, P = .04), and increased finger-tapping speed (8.7%, P = .025). We show that common SNPs in SLC30A10 are associated with blood Mn concentrations in 3 unrelated cohorts and that their influence may be mediated by altered SLC30A10 expression. Moreover, the SNPs appeared to influence neurological functions independent of blood Mn concentrations, suggesting that SLC30A10 could regulate brain Mn levels.
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Affiliation(s)
- Karin Wahlberg
- *Division of Occupational and Environmental Medicine, Lund University, 221 85 Lund, Sweden;
| | - Maria Kippler
- Institute of Environmental Medicine, Karolinska Institutet, 171 65 Solna, Sweden
| | - Ayman Alhamdow
- *Division of Occupational and Environmental Medicine, Lund University, 221 85 Lund, Sweden
| | - Syed Moshfiqur Rahman
- Institute of Environmental Medicine, Karolinska Institutet, 171 65 Solna, Sweden; International Centre for Diarrhoeal Disease Research, Bangladesh (icddr, b), Mohakhali, Dhaka 1000, Bangladesh
| | - Donald R Smith
- Microbiology and Environmental Toxicology, University of California, 1156 High Street, Santa Cruz, California 95064
| | - Marie Vahter
- *Division of Occupational and Environmental Medicine, Lund University, 221 85 Lund, Sweden
| | - Roberto G Lucchini
- Microbiology and Environmental Toxicology, University of California, 1156 High Street, Santa Cruz, California 95064; Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, New York 10029-5674; and Occupational Health Institute, University of Brescia, Viale Europa, 11, 25123 Brescia BS, Italy
| | - Karin Broberg
- *Division of Occupational and Environmental Medicine, Lund University, 221 85 Lund, Sweden; Institute of Environmental Medicine, Karolinska Institutet, 171 65 Solna, Sweden;
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Haynes EN, Sucharew H, Kuhnell P, Alden J, Barnas M, Wright RO, Parsons PJ, Aldous KM, Praamsma ML, Beidler C, Dietrich KN. Manganese Exposure and Neurocognitive Outcomes in Rural School-Age Children: The Communities Actively Researching Exposure Study (Ohio, USA). ENVIRONMENTAL HEALTH PERSPECTIVES 2015; 123:1066-71. [PMID: 25902278 PMCID: PMC4590758 DOI: 10.1289/ehp.1408993] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 04/20/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND Manganese (Mn) plays a vital role in brain growth and development, yet excessive exposure can result in neurotoxicity. Marietta, Ohio, is home to the nation's longest-operating ferromanganese refinery, and community concern about exposure led to the development of the research study. OBJECTIVES Our overall goal was to address the community's primary research question: "Does Mn affect cognitive development of children?" We evaluated the relationships between Mn exposure as measured by blood and hair Mn, along with other neurotoxicants including blood lead (Pb) and serum cotinine, and child cognition. METHODS Children 7-9 years of age were enrolled (n = 404) in the Communities Actively Researching Exposure Study (CARES) from Marietta and Cambridge, Ohio, and their surrounding communities from October 2008 through March 2013. Blood and hair were analyzed for Mn and Pb, and serum was analyzed for cotinine. We used penalized splines to assess potential nonlinear associations between biological measures and IQ subscale scores, followed by multivariable regression models with categorical variables based on quartiles of the distribution for biological measures with nonlinear associations and continuous variables for biological measures with linear associations. RESULTS Geometric mean blood (n = 327) and hair Mn (n = 370) concentrations were 9.67 ± 1.27 μg/L and 416.51 ± 2.44 ng/g, respectively. After adjusting for potential confounders, both low and high blood and hair Mn concentrations were associated with lower Full Scale IQ and subscale scores, with significant negative associations between the highest quartile and middle two quartiles of blood Mn (β -3.51; 95% CI: -6.64, -0.38) and hair Mn (β -3.66; 95% CI: -6.9, -0.43%) and Full Scale IQ. CONCLUSIONS Both low and high Mn concentrations in blood and hair were negatively associated with child IQ scores. Serum cotinine was negatively associated with child cognitive function.
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Affiliation(s)
- Erin N Haynes
- Department of Environmental Health, College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA
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Abstract
Exposure to manganese (Mn) causes clinical signs and symptoms resembling, but not identical to, Parkinson's disease. Since our last review on this subject in 2004, the past decade has been a thriving period in the history of Mn research. This report provides a comprehensive review on new knowledge gained in the Mn research field. Emerging data suggest that beyond traditionally recognized occupational manganism, Mn exposures and the ensuing toxicities occur in a variety of environmental settings, nutritional sources, contaminated foods, infant formulas, and water, soil, and air with natural or man-made contaminations. Upon fast absorption into the body via oral and inhalation exposures, Mn has a relatively short half-life in blood, yet fairly long half-lives in tissues. Recent data suggest Mn accumulates substantially in bone, with a half-life of about 8-9 years expected in human bones. Mn toxicity has been associated with dopaminergic dysfunction by recent neurochemical analyses and synchrotron X-ray fluorescent imaging studies. Evidence from humans indicates that individual factors such as age, gender, ethnicity, genetics, and pre-existing medical conditions can have profound impacts on Mn toxicities. In addition to body fluid-based biomarkers, new approaches in searching biomarkers of Mn exposure include Mn levels in toenails, non-invasive measurement of Mn in bone, and functional alteration assessments. Comments and recommendations are also provided with regard to the diagnosis of Mn intoxication and clinical intervention. Finally, several hot and promising research areas in the next decade are discussed.
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Affiliation(s)
- Stefanie L. O’Neal
- School of Health Sciences, Purdue University, 550 Stadium Mall Drive, Room 1173, West Lafayette, IN 47907, USA
| | - Wei Zheng
- School of Health Sciences, Purdue University, 550 Stadium Mall Drive, Room 1173, West Lafayette, IN 47907, USA
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Lee EY, Flynn MR, Du G, Lewis MM, Fry R, Herring AH, Van Buren E, Van Buren S, Smeester L, Kong L, Yang Q, Mailman RB, Huang X. T1 Relaxation Rate (R1) Indicates Nonlinear Mn Accumulation in Brain Tissue of Welders With Low-Level Exposure. Toxicol Sci 2015; 146:281-9. [PMID: 25953701 PMCID: PMC4607746 DOI: 10.1093/toxsci/kfv088] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Although the essential element manganese (Mn) is neurotoxic at high doses, the effects of lower exposure are unclear. MRI T1-weighted (TIW) imaging has been used to estimate brain Mn exposure via the pallidal index (PI), defined as the T1W intensity ratio in the globus pallidus (GP) versus frontal white matter (FWM). PI may not, however, be sensitive to Mn in GP because Mn also may accumulate in FWM. This study explored: (1) whether T1 relaxation rate (R1) could quantify brain Mn accumulation more sensitively; and (2) the dose-response relationship between estimated Mn exposure and T1 relaxation rate (R1). Thirty-five active welders and 30 controls were studied. Occupational questionnaires were used to estimate hours welding in the past 90 days (HrsW) and lifetime measures of Mn exposure. T1W imaging and T1-measurement were utilized to generate PI and R1 values in brain regions of interest (ROIs). PI did not show a significant association with any measure of Mn and/or welding-related exposure. Conversely, in several ROIs, R1 showed a nonlinear relationship to HrsW, with R1 signal increasing only after a critical exposure was reached. The GP had the greatest rate of Mn accumulation. Welders with higher exposure showed significantly higher R1 compared either with controls or with welders with lower exposure. Our data are additional evidence that Mn accumulation can be assessed more sensitively by R1 than by PI. Moreover, the nonlinear relationship between welding exposure and Mn brain accumulation should be considered in future studies and policies.
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Affiliation(s)
- Eun-Young Lee
- *Department of Neurology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Michael R Flynn
- Department of Environmental Sciences and Engineering, School of Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Guangwei Du
- *Department of Neurology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Mechelle M Lewis
- *Department of Neurology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Rebecca Fry
- Department of Environmental Sciences and Engineering, School of Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Amy H Herring
- Department of Biostatistics, School of Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Eric Van Buren
- Department of Biostatistics, School of Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Scott Van Buren
- Department of Biostatistics, School of Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Lisa Smeester
- Department of Environmental Sciences and Engineering, School of Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Lan Kong
- Department of Public Health Sciences, Pennsylvania State University, Hershey, Pennsylvania and
| | - Qing Yang
- Departments of Radiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Richard B Mailman
- *Department of Neurology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Xuemei Huang
- *Department of Neurology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, Departments of Radiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, Department of Kinesiology, Pennsylvania State University, University Park, Pennsylvania
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88
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Moshkin MP, Petrovski DV, Akulov AE, Romashchenko AV, Gerlinskaya LA, Ganimedov VL, Muchnaya MI, Sadovsky AS, Koptyug IV, Savelov AA, Troitsky SY, Moshkn YM, Bukhtiyarov VI, Kolchanov NA, Sagdeev RZ, Fomin VM. Nasal aerodynamics protects brain and lung from inhaled dust in subterranean diggers, Ellobius talpinus. Proc Biol Sci 2015; 281:rspb.2014.0919. [PMID: 25143031 DOI: 10.1098/rspb.2014.0919] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Inhalation of air-dispersed sub-micrometre and nano-sized particles presents a risk factor for animal and human health. Here, we show that nasal aerodynamics plays a pivotal role in the protection of the subterranean mole vole Ellobius talpinus from an increased exposure to nano-aerosols. Quantitative simulation of particle flow has shown that their deposition on the total surface of the nasal cavity is higher in the mole vole than in a terrestrial rodent Mus musculus (mouse), but lower on the olfactory epithelium. In agreement with simulation results, we found a reduced accumulation of manganese in olfactory bulbs of mole voles in comparison with mice after the inhalation of nano-sized MnCl2 aerosols. We ruled out the possibility that this reduction is owing to a lower transportation from epithelium to brain in the mole vole as intranasal instillations of MnCl2 solution and hydrated nanoparticles of manganese oxide MnO · (H2O)x revealed similar uptake rates for both species. Together, we conclude that nasal geometry contributes to the protection of brain and lung from accumulation of air-dispersed particles in mole voles.
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Affiliation(s)
- M P Moshkin
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk 630090, Russia Department of Physiology, Novosibirsk State University, Novosibirsk 630090, Russia Department of Zoology and Animal Ecology, Tomsk State University, Tomsk 634050, Russia
| | - D V Petrovski
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - A E Akulov
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - A V Romashchenko
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk 630090, Russia Design Technological Institute of Digital Techniques, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - L A Gerlinskaya
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - V L Ganimedov
- Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - M I Muchnaya
- Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - A S Sadovsky
- Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - I V Koptyug
- International Tomographic Center, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - A A Savelov
- International Tomographic Center, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - S Yu Troitsky
- Boreskov Institute of Catalysis, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - Y M Moshkn
- Department of Biochemistry, Erasmus Medical Center, Dr. Molewaterplein 50, Rotterdam 3015GE, The Netherlands
| | - V I Bukhtiyarov
- Boreskov Institute of Catalysis, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - N A Kolchanov
- Institute of Cytology and Genetics, Siberian Branch of RAS, Novosibirsk 630090, Russia Department of Physiology, Novosibirsk State University, Novosibirsk 630090, Russia
| | - R Z Sagdeev
- International Tomographic Center, Siberian Branch of RAS, Novosibirsk 630090, Russia
| | - V M Fomin
- Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch of RAS, Novosibirsk 630090, Russia
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89
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Abstract
The understanding of manganese (Mn) biology, in particular its cellular regulation and role in neurological disease, is an area of expanding interest. Mn is an essential micronutrient that is required for the activity of a diverse set of enzymatic proteins (e.g., arginase and glutamine synthase). Although necessary for life, Mn is toxic in excess. Thus, maintaining appropriate levels of intracellular Mn is critical. Unlike other essential metals, cell-level homeostatic mechanisms of Mn have not been identified. In this review, we discuss common forms of Mn exposure, absorption, and transport via regulated uptake/exchange at the gut and blood-brain barrier and via biliary excretion. We present the current understanding of cellular uptake and efflux as well as subcellular storage and transport of Mn. In addition, we highlight the Mn-dependent and Mn-responsive pathways implicated in the growing evidence of its role in Parkinson's disease and Huntington's disease. We conclude with suggestions for future focuses of Mn health-related research.
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Affiliation(s)
- Kyle J Horning
- Department of Neurology, Vanderbilt University, Nashville, Tennessee 37232; , ,
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90
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Ex vivo magnetic resonance imaging in South African manganese mine workers. Neurotoxicology 2015; 49:8-14. [PMID: 25912463 DOI: 10.1016/j.neuro.2015.04.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 03/14/2015] [Accepted: 04/13/2015] [Indexed: 11/22/2022]
Abstract
BACKGROUND Manganese (Mn) exposure is associated with increased T1-weighted magnetic resonance imaging (MRI) signal in the basal ganglia. T1 signal intensity has been correlated with occupational Mn exposure but not with clinical symptomatology or neuropathology. OBJECTIVES This study investigated predictors of ex vivo T1 MRI basal ganglia signal intensity in neuropathologic tissue obtained from deceased South African mine workers. METHODS A 3.0 T MRI was performed on ex vivo brain tissue obtained from 19 Mn mine workers and 10 race- and sex-matched mine workers of other commodities. Basal ganglia regions of interest were identified for each subject with T1-weighted intensity indices generated for each region. In a pathology subset, regional T1 indices were compared to neuronal and glial cell density and tissue metal concentrations. RESULTS Intensity indices were higher in Mn mine workers than non-Mn mine workers for the globus pallidus, caudate, anterior putamen, and posterior putamen with the highest values in subjects with the longest cumulative Mn exposure. Intensity indices were inversely correlated with the neuronal cell density in the caudate (p=0.040) and putamen (p=0.050). Tissue Mn concentrations were similar in Mn and non-Mn mine workers. Tissue iron (Fe) concentration trended lower across all regions in Mn mine workers. CONCLUSIONS Mn mine workers demonstrated elevated basal ganglia T1 indices when compared to non-Mn mine workers. Predictors of ex vivo T1 MRI signal intensity in Mn mine workers include duration of Mn exposure and neuronal density.
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91
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Abstract
Manganese is an essential trace element with neurotoxicant properties at high levels that were first described in the mid-nineteenth century. The largest sources of occupational and environmental exposures are mining, fossil fuel combustion, and iron and steel industries. Manganese neurotoxicity has been described in many workers with high levels of occupational manganese exposure and can cause a distinct neurologic phenotype known as manganism. Recently, our understanding of the clinical syndrome and pathophysiology of manganese toxicity has shifted. Modern day manganese exposures, which are an order of magnitude lower than previously described in cases of manganism, result in different clinical, imaging, and pathologic phenotypes. Here we will review three neurologic "myths" of manganism in the twenty-first century and will provide evidence that Mn is associated with a clinical syndrome of parkinsonism that resembles Parkinson disease, dopaminergic dysfunction on molecular imaging, and an inflammatory neuropathology in the striatum.
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Affiliation(s)
- Kristin M Andruska
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - And Brad A Racette
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA ; School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Parktown, South Africa
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92
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Chen P, DeWitt MR, Bornhorst J, Soares FA, Mukhopadhyay S, Bowman AB, Aschner M. Age- and manganese-dependent modulation of dopaminergic phenotypes in a C. elegans DJ-1 genetic model of Parkinson's disease. Metallomics 2015; 7:289-98. [PMID: 25531510 PMCID: PMC4479152 DOI: 10.1039/c4mt00292j] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease, yet its etiology and pathogenesis are poorly understood. PD is characterized by selective dopaminergic (DAergic) degeneration and progressive hypokinetic motor impairment. Mutations in dj-1 cause autosomal recessive early-onset PD. DJ-1 is thought to protect DAergic neurons via an antioxidant mechanism, but the precise basis of this protection has not yet been resolved. Aging and manganese (Mn) exposure are significant non-genetic risk factors for PD. Caenorhabditis elegans (C. elegans) is an optimal model for PD and aging studies because of its simple nervous system, conserved DAergic machinery, and short 20-day lifespan. Here we tested the hypothesis that C. elegans DJ-1 homologues were protective against Mn-induced DAergic toxicity in an age-dependent manner. We showed that the deletion of C. elegans DJ-1 related (djr) genes, djr-1.2, decreased survival after Mn exposure. djr-1.2, the DJ-1 homologue was expressed in DAergic neurons and its deletion decreased lifespan and dopamine (DA)-dependent dauer movement behavior after Mn exposure. We also tested the role of DAF-16 as a regulator of dj-1.2 interaction with Mn toxicity. Lifespan defects resulting from djr-1.2 deletion could be restored to normal by overexpression of either DJR-1.2 or DAF-16. Furthermore, dauer movement alterations after djr-1.2 deletion were abolished by constitutive activation of DAF-16 through mutation of its inhibitor, DAF-2 insulin receptor. Taken together, our results reveal PD-relevant interactions between aging, the PD environmental risk factor manganese, and homologues of the established PD genetic risk factor DJ-1. Our data demonstrate a novel role for the DJ-1 homologue, djr-1.2, in mitigating Mn-dependent lifespan reduction and DA signaling alterations, involving DAF-2/DAF-16 signaling.
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Affiliation(s)
- Pan Chen
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA.
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93
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Inducible nitric oxide synthase gene methylation and parkinsonism in manganese-exposed welders. Parkinsonism Relat Disord 2015; 21:355-60. [PMID: 25634431 DOI: 10.1016/j.parkreldis.2015.01.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 01/01/2015] [Accepted: 01/11/2015] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Neurologist-assessed parkinsonism signs are prevalent among workers exposed to manganese (Mn)-containing welding fume. Neuroinflammation may possibly play a role. Inducible nitric oxide synthase, coded by NOS2, is involved in inflammation, and particulate exposure increases the gene's expression through methylation of CpG sites in the 5' region. METHODS We assessed DNA methylation at three CpG sites in the NOS2 exon 1 from blood from 201 welders. All were non-Hispanic Caucasian men 25-65 years old who were examined by a neurologist specializing in movement disorders. We categorized the workers according to their Unified Parkinson Disease Rating Scale motor subsection 3 (UPDRS3) scores as parkinsonism cases (UPDRS3 ≥ 15; n = 49), controls (UPDRS3 < 6; n = 103), or intermediate (UPDRS3 ≥ 6 to < 15; n = 49). RESULTS While accounting for age, examiner and experimental plate, parkinsonism cases had lower mean NOS2 methylation than controls (p-value for trend = 0.04), specifically at CpG site 8329 located in an exonic splicing enhancer of NOS2 (p-value for trend = 0.07). These associations were not observed for the intermediate UPDRS3 group (both p-value for trend ≥ 0.59). CONCLUSIONS Inflammation mediated by inducible nitric oxide synthase may possibly contribute to the association between welding fume and parkinsonism, but requires verification in a longitudinal study.
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94
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Abstract
In recent years, the contribution of exposure to environmental toxicants has been recognized as a significant contributor to the etiopathogenesis of parkinsonism. Of these toxicants, exposure to pesticides, metals, solvents used in manufacturing processes, as well as flame-retardant chemicals used in consumer and commercial products, has received the greatest attention as possible risk factors. Related to this, individuals who are exposed to these compounds at high concentrations or for prolonged periods of time in an occupational setting appear to be one of the more vulnerable populations to these effects. Our understanding of which compounds are involved and the potential molecular pathways that are susceptible to these chemicals and may underlie the pathogenesis has greatly improved. However, there are still hundreds of chemicals that we are exposed to in the environment for which we do not have any information on their potential neurotoxicity on the nigrostriatal dopamine system. Thus, using our past accomplishments as a blueprint, future endeavors should focus on elaborating upon these initial findings in order to identify specific and relevant chemical toxicants in our environment that can impact the risk of parkinsonism and work towards a means to attenuate or abolish their effects on the human population.
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Affiliation(s)
- W Michael Caudle
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
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95
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Tutkun E, Abuşoğlu S, Yılmaz H, Gündüzöz M, Gıynas N, Bal CD, Ünlü A. Prolactin levels in manganese-exposed male welders. Pituitary 2014; 17:564-8. [PMID: 24337778 DOI: 10.1007/s11102-013-0545-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE Early studies on manganese (Mn) exposure have demonstrated that this transition metal affects dopamine neurotransmission. Dopamine serves as a tonic inhibitor of prolactin release in the anterior hypophysis. Our aim was to determine the relation between serum prolactin levels and manganese-exposure. METHODS Whole blood was collected from 95 non-exposed control subjects and 179 manganese-exposed male welders. Whole blood manganese was analyzed by Inductively Coupled Plasma--Mass Spectrometer on Agilent 7700 (Agilent Technologies, USA). Serum prolactin levels (PRL), aspartate transaminase (AST), alanine transaminase (ALT), urea, creatinine, soduim (Na), potassium (K) were analyzed by immunological and spectrophotometric methods on Roche E170 Modular System (Roche Diagnostics, Mannheim, Germany). RESULTS The mean ages for control and manganese-exposed group were 40.5 ± 7.8 and 39.5 ± 8.7, respectively (p = 0.258). The mean working period (years) for control and manganese-exposed group were 17.4 ± 9.8 and 18.2 ± 7.7 years, respectively (p = 0.581). Serum AST and potassium levels were significantly higher in control group than manganese-exposed group (p = 0.002 and p = 0.048, respectively) and body-mass index (BMI) was significantly lower in control group than manganese-exposed group (p = 0.033). There was a significantly positive correlation between whole blood manganese levels and serum prolactin (r = 0.860, p < 0.001). Serum ALT levels were positively correlated with serum AST, urea and sodium (r = 0.315, p < 0.001; r = 0.121, p = 0.046; r = 0.130, p = 0.031). CONCLUSIONS Serum prolactin level is a diagnostic marker for determining the effect of manganese-exposure.
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Affiliation(s)
- Engin Tutkun
- Department of Toxicology, Occupational Diseases Hospital, Ankara, Turkey
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96
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Persoons R, Arnoux D, Monssu T, Culié O, Roche G, Duffaud B, Chalaye D, Maitre A. Determinants of occupational exposure to metals by gas metal arc welding and risk management measures: A biomonitoring study. Toxicol Lett 2014; 231:135-41. [DOI: 10.1016/j.toxlet.2014.09.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 07/31/2014] [Accepted: 09/10/2014] [Indexed: 02/01/2023]
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97
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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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98
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Chen P, Chakraborty S, Peres TV, Bowman AB, Aschner M. Manganese-induced Neurotoxicity: From C. elegans to Humans. Toxicol Res (Camb) 2014; 4:191-202. [PMID: 25893090 DOI: 10.1039/c4tx00127c] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Manganese (Mn) is one of the most abundant metals on the earth. It is required for normal cellular activities, but overexposure leads to toxicity. Neurons are more susceptible to Mn-induced toxicity than other cells, and accumulation of Mn in the brain results in Manganism that presents with Parkinson's disease (PD)-like symptoms. In the last decade, a number of Mn transporters have been identified, which improves our understanding of Mn transport in and out of cells. However, the mechanism of Mn-induced neurotoxicity is only partially uncovered, with further research needed to explore the whole picture of Mn-induced toxicity. In this review, we will address recent progress in Mn-induced neurotoxicity from C. elegans to humans, and explore future directions that will help understand the mechanisms of its neurotoxicity.
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Affiliation(s)
- Pan Chen
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Sudipta Chakraborty
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Tanara V Peres
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA ; Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Aaron B Bowman
- Department of Neurology, Vanderbilt University Medical Center, Nashville TN, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
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99
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Bakthavatsalam S, Das Sharma S, Sonawane M, Thirumalai V, Datta A. A zebrafish model of manganism reveals reversible and treatable symptoms that are independent of neurotoxicity. Dis Model Mech 2014; 7:1239-51. [PMID: 25261567 PMCID: PMC4213728 DOI: 10.1242/dmm.016683] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Manganese (manganese ion; referred to as Mn) is essential for neuronal function, yet it is toxic at high concentrations. Environmental and occupational exposure to high concentrations of Mn causes manganism, a well-defined movement disorder in humans, with symptoms resembling Parkinson's disease (PD). However, manganism is distinct from PD and the neural basis of its pathology is poorly understood. To address this issue, we generated a zebrafish model of manganism by incubating larvae in rearing medium containing Mn. We find that Mn-treated zebrafish larvae exhibit specific postural and locomotor defects. Larvae begin to float on their sides, show a curved spine and swim in circles. We discovered that treatment with Mn causes postural defects by interfering with mechanotransduction at the neuromasts. Furthermore, we find that the circling locomotion could be caused by long-duration bursting in the motor neurons, which can lead to long-duration tail bends in the Mn-treated larvae. Mn-treated larvae also exhibited fewer startle movements. Additionally, we show that the intensity of tyrosine hydroxylase immunoreactivity is reversibly reduced after Mn-treatment. This led us to propose that reduced dopamine neuromodulation drives the changes in startle movements. To test this, when we supplied an external source of dopamine to Mn-treated larvae, the larvae exhibited a normal number of startle swims. Taken together, these results indicate that Mn interferes with neuronal function at the sensory, motor and modulatory levels, and open avenues for therapeutically targeted studies on the zebrafish model of manganism.
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Affiliation(s)
- Subha Bakthavatsalam
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Colaba, Mumbai-400005, India
| | - Shreya Das Sharma
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bellary Road, Bangalore-560065, India
| | - Mahendra Sonawane
- Department of Biological Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Colaba, Mumbai-400005, India
| | - Vatsala Thirumalai
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bellary Road, Bangalore-560065, India.
| | - Ankona Datta
- Department of Chemical Sciences, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Colaba, Mumbai-400005, India.
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100
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Liu Y, Byrne P, Wang H, Koltick D, Zheng W, Nie LH. A compact DD neutron generator-based NAA system to quantify manganese (Mn) in bone in vivo. Physiol Meas 2014; 35:1899-911. [PMID: 25154883 DOI: 10.1088/0967-3334/35/9/1899] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
A deuterium-deuterium (DD) neutron generator-based neutron activation analysis (NAA) system has been developed to quantify metals, including manganese (Mn), in bone in vivo. A DD neutron generator with a flux of up to 3*10(9) neutrons s(-1) was set up in our lab for this purpose. Optimized settings, including moderator, reflector, and shielding material and thickness, were selected based on Monte Carlo (MC) simulations conducted in our previous work. Hand phantoms doped with different Mn concentrations were irradiated using the optimized DD neutron generator irradiation system. The Mn characteristic γ-rays were collected by an HPGe detector system with 100% relative efficiency. The calibration line of the Mn/calcium (Ca) count ratio versus bone Mn concentration was obtained (R(2) = 0.99) using the hand phantoms. The detection limit (DL) was calculated to be about 1.05 μg g(-1) dry bone (ppm) with an equivalent dose of 85.4 mSv to the hand. The DL can be reduced to 0.74 ppm by using two 100% HPGe detectors. The whole body effective dose delivered to the irradiated subject was calculated to be about 17 μSv. Given the average normal bone Mn concentration of 1 ppm in the general population, this system is promising for in vivo bone Mn quantification in humans.
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Affiliation(s)
- Yingzi Liu
- School of Health Sciences, Purdue University, West Lafayette, IN, USA
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