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Menšíková K, Steele JC, Rosales R, Colosimo C, Spencer P, Lannuzel A, Ugawa Y, Sasaki R, Giménez-Roldán S, Matej R, Tuckova L, Hrabos D, Kolarikova K, Vodicka R, Vrtel R, Strnad M, Hlustik P, Otruba P, Prochazka M, Bares M, Boluda S, Buee L, Ransmayr G, Kaňovský P. Endemic parkinsonism: clusters, biology and clinical features. Nat Rev Neurol 2023; 19:599-616. [PMID: 37684518 DOI: 10.1038/s41582-023-00866-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2023] [Indexed: 09/10/2023]
Abstract
The term 'endemic parkinsonism' refers to diseases that manifest with a dominant parkinsonian syndrome, which can be typical or atypical, and are present only in a particular geographically defined location or population. Ten phenotypes of endemic parkinsonism are currently known: three in the Western Pacific region; two in the Asian-Oceanic region; one in the Caribbean islands of Guadeloupe and Martinique; and four in Europe. Some of these disease entities seem to be disappearing over time and therefore are probably triggered by unique environmental factors. By contrast, other types persist because they are exclusively genetically determined. Given the geographical clustering and potential overlap in biological and clinical features of these exceptionally interesting diseases, this Review provides a historical reference text and offers current perspectives on each of the 10 phenotypes of endemic parkinsonism. Knowledge obtained from the study of these disease entities supports the hypothesis that both genetic and environmental factors contribute to the development of neurodegenerative diseases, not only in endemic parkinsonism but also in general. At the same time, this understanding suggests useful directions for further research in this area.
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Affiliation(s)
- Katerina Menšíková
- Department of Neurology and Clinical Neuroscience Center, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
- University Hospital, Olomouc, Czech Republic
| | | | - Raymond Rosales
- Research Center for Health Sciences, Faculty of Medicine and Surgery, University of Santo Tomás, Manila, The Philippines
- St Luke's Institute of Neuroscience, Metro, Manila, The Philippines
| | - Carlo Colosimo
- Department of Neurology, Santa Maria University Hospital, Terni, Italy
| | - Peter Spencer
- Department of Neurology, School of Medicine, Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
| | - Annie Lannuzel
- Départment de Neurologie, Centre Hospitalier Universitaire de la Guadeloupe, Pointe-á-Pitre, France
| | - Yoshikazu Ugawa
- Department of Human Neurophysiology, Fukushima Medical University, Fukushima, Japan
| | - Ryogen Sasaki
- Department of Neurology, Kuwana City Medical Center, Kuwana, Japan
| | | | - Radoslav Matej
- Department of Pathology, 3rd Medical Faculty, Charles University and University Hospital Kralovske Vinohrady, Prague, Czech Republic
- Department of Pathology and Molecular Medicine, 3rd Medical Faculty, Charles University and Thomayer University Hospital, Prague, Czech Republic
| | - Lucie Tuckova
- University Hospital, Olomouc, Czech Republic
- Department of Clinical and Molecular Pathology, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Dominik Hrabos
- University Hospital, Olomouc, Czech Republic
- Department of Clinical and Molecular Pathology, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Kristyna Kolarikova
- University Hospital, Olomouc, Czech Republic
- Department of Clinical and Molecular Genetics, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Radek Vodicka
- University Hospital, Olomouc, Czech Republic
- Department of Clinical and Molecular Genetics, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Radek Vrtel
- University Hospital, Olomouc, Czech Republic
- Department of Clinical and Molecular Genetics, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Miroslav Strnad
- Department of Neurology and Clinical Neuroscience Center, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
- University Hospital, Olomouc, Czech Republic
- Laboratory of Growth Regulators, Faculty of Science, Palacky University, Olomouc, Czech Republic
| | - Petr Hlustik
- Department of Neurology and Clinical Neuroscience Center, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
- University Hospital, Olomouc, Czech Republic
| | - Pavel Otruba
- Department of Neurology and Clinical Neuroscience Center, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
- University Hospital, Olomouc, Czech Republic
| | - Martin Prochazka
- University Hospital, Olomouc, Czech Republic
- Department of Clinical and Molecular Genetics, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Martin Bares
- First Department of Neurology, Masaryk University Medical School, Brno, Czech Republic
- St Anne University Hospital, Brno, Czech Republic
| | - Susana Boluda
- Département de Neuropathologie, Hôpital La Pitié - Salpêtrière, Paris, France
| | - Luc Buee
- Lille Neuroscience & Cognition Research Centre, INSERM U1172, Lille, France
| | - Gerhard Ransmayr
- Department of Neurology, Faculty of Medicine, Johannes Kepler University, Linz, Austria
| | - Petr Kaňovský
- Department of Neurology and Clinical Neuroscience Center, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic.
- University Hospital, Olomouc, Czech Republic.
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Bellamri M, Brandt K, Cammerrer K, Syeda T, Turesky RJ, Cannon JR. Nuclear DNA and Mitochondrial Damage of the Cooked Meat Carcinogen 2-Amino-1-methyl-6-phenylimidazo[4,5- b]pyridine in Human Neuroblastoma Cells. Chem Res Toxicol 2023; 36:1361-1373. [PMID: 37421305 PMCID: PMC10626466 DOI: 10.1021/acs.chemrestox.3c00109] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2023]
Abstract
Animal fat and iron-rich diets are risk factors for Parkinson's disease (PD). The heterocyclic aromatic amines (HAAs) harman and norharman are neurotoxicants formed in many foods and beverages, including cooked meats, suggesting a role for red meat in PD. The structurally related carcinogenic HAAs 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-amino-3,8-dimethylmidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-9H-pyrido[2,3-b]indole (AαC) also form in cooked meats. We investigated the cytotoxicity, DNA-damaging potential, and mitochondrial damage of HAAs and their genotoxic HONH-HAA metabolites in galactose-dependent SH-SY5Y cells, a human neuroblastoma cell line relevant for PD-related neurotoxicity. All HAAs and HONH-HAAs induced weak toxicity except HONH-PhIP, which was 1000-fold more potent than the other chemicals. HONH-PhIP DNA adduct formation occurred at 300-fold higher levels than adducts formed with HONH-MeIQx and HONH-AαC, assuming similar cellular uptake rates. PhIP-DNA adduct levels occurred at concentrations as low as 1 nM and were threefold or higher and more persistent in mitochondrial DNA than nuclear DNA. N-Acetyltransferases (NATs), sulfotransferases, and kinases catalyzed PhIP-DNA binding and converted HONH-PhIP to highly reactive ester intermediates. DNA binding assays with cytosolic, mitochondrial, and nuclear fractions of SH-SY5Y fortified with cofactors revealed that cytosolic AcCoA-dependent enzymes, including NAT1, mainly carried out HONH-PhIP bioactivation to form N-acetoxy-PhIP, which binds to DNA. Furthermore, HONH-PHIP and N-acetoxy-PhIP inhibited mitochondrial complex-I, -II, and -III activities in isolated SH-SY5Y mitochondria. Mitochondrial respiratory chain complex dysfunction and DNA damage are major mechanisms in PD pathogenesis. Our data support the possible role of PhIP in PD etiology.
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Affiliation(s)
- Medjda Bellamri
- Masonic Cancer Center and Department of Medicinal Chemistry, Cancer and Cardiovascular Research Building, University of Minnesota, 2231 6th Street, Minneapolis, Minnesota 55455, United States
| | - Kyle Brandt
- Masonic Cancer Center and Department of Medicinal Chemistry, Cancer and Cardiovascular Research Building, University of Minnesota, 2231 6th Street, Minneapolis, Minnesota 55455, United States
| | - Kari Cammerrer
- Masonic Cancer Center and Department of Medicinal Chemistry, Cancer and Cardiovascular Research Building, University of Minnesota, 2231 6th Street, Minneapolis, Minnesota 55455, United States
| | - Tauqeerunnisa Syeda
- School of Health Sciences, Purdue Institute for Integrative Neurosciences, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, Indiana 47907, United States
| | - Robert J Turesky
- Masonic Cancer Center and Department of Medicinal Chemistry, Cancer and Cardiovascular Research Building, University of Minnesota, 2231 6th Street, Minneapolis, Minnesota 55455, United States
| | - Jason R Cannon
- School of Health Sciences, Purdue Institute for Integrative Neurosciences, Purdue University, West Lafayette, Indiana 47907, United States
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, Indiana 47907, United States
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Kobets T, Smith BPC, Williams GM. Food-Borne Chemical Carcinogens and the Evidence for Human Cancer Risk. Foods 2022; 11:foods11182828. [PMID: 36140952 PMCID: PMC9497933 DOI: 10.3390/foods11182828] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 09/07/2022] [Accepted: 09/08/2022] [Indexed: 11/16/2022] Open
Abstract
Commonly consumed foods and beverages can contain chemicals with reported carcinogenic activity in rodent models. Moreover, exposures to some of these substances have been associated with increased cancer risks in humans. Food-borne carcinogens span a range of chemical classes and can arise from natural or anthropogenic sources, as well as form endogenously. Important considerations include the mechanism(s) of action (MoA), their relevance to human biology, and the level of exposure in diet. The MoAs of carcinogens have been classified as either DNA-reactive (genotoxic), involving covalent reaction with nuclear DNA, or epigenetic, involving molecular and cellular effects other than DNA reactivity. Carcinogens are generally present in food at low levels, resulting in low daily intakes, although there are some exceptions. Carcinogens of the DNA-reactive type produce effects at lower dosages than epigenetic carcinogens. Several food-related DNA-reactive carcinogens, including aflatoxins, aristolochic acid, benzene, benzo[a]pyrene and ethylene oxide, are recognized by the International Agency for Research on Cancer (IARC) as causes of human cancer. Of the epigenetic type, the only carcinogen considered to be associated with increased cancer in humans, although not from low-level food exposure, is dioxin (TCDD). Thus, DNA-reactive carcinogens in food represent a much greater risk than epigenetic carcinogens.
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Affiliation(s)
- Tetyana Kobets
- Department of Pathology, Microbiology and Immunology, New York Medical College, Valhalla, NY 10595, USA
- Correspondence: ; Tel.: +1-914-594-3105; Fax: +1-914-594-4163
| | - Benjamin P. C. Smith
- Future Ready Food Safety Hub, Nanyang Technological University, Singapore 639798, Singapore
| | - Gary M. Williams
- Department of Pathology, Microbiology and Immunology, New York Medical College, Valhalla, NY 10595, USA
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Li X, Cao G, Liu X, Tang TS, Guo C, Liu H. Polymerases and DNA Repair in Neurons: Implications in Neuronal Survival and Neurodegenerative Diseases. Front Cell Neurosci 2022; 16:852002. [PMID: 35846567 PMCID: PMC9279898 DOI: 10.3389/fncel.2022.852002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 05/23/2022] [Indexed: 12/22/2022] Open
Abstract
Most of the neurodegenerative diseases and aging are associated with reactive oxygen species (ROS) or other intracellular damaging agents that challenge the genome integrity of the neurons. As most of the mature neurons stay in G0/G1 phase, replication-uncoupled DNA repair pathways including BER, NER, SSBR, and NHEJ, are pivotal, efficient, and economic mechanisms to maintain genomic stability without reactivating cell cycle. In these progresses, polymerases are prominent, not only because they are responsible for both sensing and repairing damages, but also for their more diversified roles depending on the cell cycle phase and damage types. In this review, we summarized recent knowledge on the structural and biochemical properties of distinct polymerases, including DNA and RNA polymerases, which are known to be expressed and active in nervous system; the biological relevance of these polymerases and their interactors with neuronal degeneration would be most graphically illustrated by the neurological abnormalities observed in patients with hereditary diseases associated with defects in DNA repair; furthermore, the vicious cycle of the trinucleotide repeat (TNR) and impaired DNA repair pathway is also discussed. Unraveling the mechanisms and contextual basis of the role of the polymerases in DNA damage response and repair will promote our understanding about how long-lived postmitotic cells cope with DNA lesions, and why disrupted DNA repair contributes to disease origin, despite the diversity of mutations in genes. This knowledge may lead to new insight into the development of targeted intervention for neurodegenerative diseases.
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Affiliation(s)
- Xiaoling Li
- Nano-Biotechnology Key Lab of Hebei Province, Yanshan University, Qinhuangdao, China
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
- Xiaoling Li
| | - Guanghui Cao
- Nano-Biotechnology Key Lab of Hebei Province, Yanshan University, Qinhuangdao, China
| | - Xiaokang Liu
- Nano-Biotechnology Key Lab of Hebei Province, Yanshan University, Qinhuangdao, China
| | - Tie-Shan Tang
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Caixia Guo
- Beijing Institute of Genomics, University of Chinese Academy of Sciences, Chinese Academy of Sciences/China National Center for Bioinformation, Beijing, China
- *Correspondence: Caixia Guo
| | - Hongmei Liu
- State Key Laboratory of Membrane Biology, Institute of Zoology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
- Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
- Hongmei Liu
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Spencer P, Okot C, Palmer V, Valdes Angues R, Mazumder R. Nodding syndrome: A key role for sources of nutrition? eNeurologicalSci 2022; 27:100401. [PMID: 35480298 PMCID: PMC9035392 DOI: 10.1016/j.ensci.2022.100401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 04/01/2022] [Accepted: 04/07/2022] [Indexed: 12/16/2022] Open
Abstract
Nodding Syndrome (NS) has occurred among severely food-stressed communities in northern Uganda and several other East African populations that, with their forced physical displacement, have resorted to nutritional support from available wild plants and fungi, some of which have neurotoxic potential. Among the latter is an agaric mushroom with an unknown content of hydrazine-generating agaritine, namely Agaricus bingensis, the unusually wide consumption of which may relate to the low serum levels of vitamin B6 in Ugandan NS subjects relative to controls. Hydrazine-related compounds induce patterns of DNA damage that promote neuropathological changes (tauopathy) reminiscent of those associated with established NS. While the cause of this childhood brain disease is unknown, we encourage increased attention to the role of malnutrition and B6 hypovitaminosis in the etiology of this devastating brain disease. Idiopathic epileptic encephalopathy with tauopathy (Nodding syndrome) impacts East African children Associated factors include nematode infection, food insecurity, and food use of wild plants and fungi Food use of hydrazinic fungi induces B6 hypovitaminosis, which may be marked in Nodding syndrome Vitamin B6 deficiency promotes tau phosphorylation in mouse models of human tauopathy Hydrazine generates carbon free radicals associated with DNA-damage and neurodegenerative disease Increased research attention to nutritional practices associated with Nodding syndrome is merited.
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Affiliation(s)
- P.S. Spencer
- Department of Neurology, School of Medicine, Oregon Health & Science University, Portland, OR, USA
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, OR, USA
- Corresponding author at: Oregon Health & Science University (Neurology), S.W. Sam Jackson Park Road, Portland, OR 97239, USA.
| | | | - V.S. Palmer
- Department of Neurology, School of Medicine, Oregon Health & Science University, Portland, OR, USA
| | - R. Valdes Angues
- Department of Neurology, School of Medicine, Oregon Health & Science University, Portland, OR, USA
| | - R. Mazumder
- Department of Neurology, David Geffen School of Medicine, University of California Los Angeles, USA
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Kokubo Y, Morimoto S, Sasaki R, Hasegawa M, Ishiura H, Tsuji S, Yoshida M, Yamazoe N, Miyazaki M, Kuzuhara S. An immigrant family with Kii amyotrophic lateral sclerosis/parkinsonism-dementia complex. Neurol Sci 2021; 43:1423-1425. [PMID: 34779964 DOI: 10.1007/s10072-021-05737-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 11/06/2021] [Indexed: 10/19/2022]
Abstract
OBJECTIVES Amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) is a unique endemic on Guam island of the USA, the Kii Peninsula of Japan, and Papua state of Indonesia. The pathomechanism of ALS/PDC remains to be solved, although interaction between some environmental factors and genetic background is plausible. This is the first autopsy-proven immigrant family of ALS/PDC of the Kii Peninsula. METHODS A daughter and her father immigrated to the high incident area from outside the Kii Peninsula. The father developed ALS 18 years later after immigration, and his daughter also developed ALS 65 years after immigration. They showed pure ALS phenotype without parkinsonism and dementia. RESULTS The daughter was diagnosed neuropathologically with Kii ALS/PDC with multiple proteinopathies: tauopathy, α-synucleinopathy, and TDP-43 proteinopathy. Gene analysis of familial ALS-related genes, including C9orf72, showed no mutation. DISCUSSION The findings in an immigrant family established that certain environmental factors play a critical role in the pathogenesis of Kii ALS/PDC.
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Affiliation(s)
- Yasumasa Kokubo
- Kii ALS/PDC Research Center, Graduate School of Regional Innovation Studies, Mie University, 1577, Kurima-machiyamachiMie prefecture, Tsu, 514-8507, Japan.
| | - Satoru Morimoto
- Department of Oncologic Pathology, Mie University School of Medicine, Tsu, 514-8507, Japan
| | - Ryogen Sasaki
- Department of Neurology, Kuwana City Medical Center, Kuwana, 511-0061, Japan
| | - Masato Hasegawa
- Department of Dementia and Higher Brain Function, Tokyo Metropolitan Institute of Medical Science, Tokyo, 156-8506, Japan
| | - Hiroyuki Ishiura
- Department of Neurology, Graduate School of Medicine, University of Tokyo, Tokyo, 113-8655, Japan
| | - Shoji Tsuji
- Department of Neurology, Graduate School of Medicine, University of Tokyo, Tokyo, 113-8655, Japan
| | - Mari Yoshida
- Institute for Medical Science of Aging, Aichi Medical University, Nagakute, 480-1195, Japan
| | - Naohisa Yamazoe
- Department of Internal Medicine, Minami-Ise Hospital, Minamiise, 516-0101, Japan
| | - Mitsukazu Miyazaki
- Department of Internal Medicine, Minami-Ise Hospital, Minamiise, 516-0101, Japan
| | - Shigeki Kuzuhara
- Department of Neurology and Medicine, School of Nursing, Suzuka University of Medical Science, Suzuka, 510-0293, Japan
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Spencer PS. Parkinsonism and motor neuron disorders: Lessons from Western Pacific ALS/PDC. J Neurol Sci 2021; 433:120021. [PMID: 34635325 DOI: 10.1016/j.jns.2021.120021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 08/06/2021] [Accepted: 09/01/2021] [Indexed: 01/16/2023]
Abstract
Recognized worldwide as an unusual "overlap" syndrome, Parkinsonism and motor neuron disease, with or without dementia, is best exemplified by the former high-incidence clusters of Amyotrophic Lateral Sclerosis and Parkinsonism-Dementia Complex (ALS/PDC) in Guam, USA, in the Kii Peninsula of Honshu Island, Japan, and in Papua, Indonesia, on the western side of New Guinea. Western Pacific ALS/PDC is a disappearing neurodegenerative disorder with multiple and sometime overlapping phenotypes (ALS, atypical parkinsonism, dementia) that appear to constitute a single disease of environmental origin, in particular from exposure to genotoxins/neurotoxins in seed of cycad plants (Cycas spp.) formerly used as a traditional source of food (Guam) and/or medicine (Guam, Kii-Japan, Papua-Indonesia). Seed compounds include the principal cycad toxin cycasin, its active metabolite methylazoxymethanol (MAM) and a non-protein amino acid β-N-methylamino-L-alanine (L-BMAA); each reproduces components of ALS/PDC neuropathology when individually administered to laboratory species in single doses perinatally (MAM, L-BMAA) or repeatedly for prolonged periods to young adult animals (L-BMAA). Human exposure to MAM, a potent DNA-alkylating mutagen, also has potential relevance to the high incidence of diverse mutations found among Guamanians with/without ALS/PDC. In sum, seven decades of intensive study of ALS/PDC has revealed field and laboratory approaches leading to discovery of disease etiology that are now being applied to sporadic neurodegenerative disorders such as ALS beyond the Western Pacific region. This article is part of the Special Issue "Parkinsonism across the spectrum of movement disorders and beyond" edited by Joseph Jankovic, Daniel D. Truong and Matteo Bologna.
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Affiliation(s)
- Peter S Spencer
- Department of Neurology, School of Medicine, Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon, USA.
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Spencer PS, Kisby GE. Role of Hydrazine-Related Chemicals in Cancer and Neurodegenerative Disease. Chem Res Toxicol 2021; 34:1953-1969. [PMID: 34379394 DOI: 10.1021/acs.chemrestox.1c00150] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hydrazine-related chemicals (HRCs) with carcinogenic and neurotoxic potential are found in certain mushrooms and plants used for food and in products employed in various industries, including aerospace. Their propensity to induce DNA damage (mostly O6-, N7- and 8-oxo-guanine lesions) resulting in multiple downstream effects is linked with both cancer and neurological disease. For cycling cells, unrepaired DNA damage leads to mutation and uncontrolled mitosis. By contrast, postmitotic neurons attempt to re-enter the cell cycle but undergo apoptosis or nonapoptotic cell death. Biomarkers of exposure to HRCs can be used to explore whether these substances are risk factors for sporadic amyotrophic laterals sclerosis and other noninherited neurodegenerative diseases, which is the focus of this paper.
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Affiliation(s)
- Peter S Spencer
- Oregon Health and Science University, Portland, Oregon 97239, United States
| | - Glen E Kisby
- College of Osteopathic Medicine of the Pacific Northwest, Western University of Health Sciences, Lebanon, Oregon 97355, United States
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Kok JR, Palminha NM, Dos Santos Souza C, El-Khamisy SF, Ferraiuolo L. DNA damage as a mechanism of neurodegeneration in ALS and a contributor to astrocyte toxicity. Cell Mol Life Sci 2021; 78:5707-5729. [PMID: 34173837 PMCID: PMC8316199 DOI: 10.1007/s00018-021-03872-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 04/27/2021] [Accepted: 06/05/2021] [Indexed: 12/11/2022]
Abstract
Increasing evidence supports the involvement of DNA damage in several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). Elevated levels of DNA damage are consistently observed in both sporadic and familial forms of ALS and may also play a role in Western Pacific ALS, which is thought to have an environmental cause. The cause of DNA damage in ALS remains unclear but likely differs between genetic subgroups. Repeat expansion in the C9ORF72 gene is the most common genetic cause of familial ALS and responsible for about 10% of sporadic cases. These genetic mutations are known to cause R-loops, thus increasing genomic instability and DNA damage, and generate dipeptide repeat proteins, which have been shown to lead to DNA damage and impairment of the DNA damage response. Similarly, several genes associated with ALS including TARDBP, FUS, NEK1, SQSTM1 and SETX are known to play a role in DNA repair and the DNA damage response, and thus may contribute to neuronal death via these pathways. Another consistent feature present in both sporadic and familial ALS is the ability of astrocytes to induce motor neuron death, although the factors causing this toxicity remain largely unknown. In this review, we summarise the evidence for DNA damage playing a causative or secondary role in the pathogenesis of ALS as well as discuss the possible mechanisms involved in different genetic subtypes with particular focus on the role of astrocytes initiating or perpetuating DNA damage in neurons.
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Affiliation(s)
- Jannigje Rachel Kok
- University of Sheffield, Sheffield Institute for Translational Neuroscience (SITraN), Sheffield, UK
| | - Nelma M Palminha
- Department of Molecular Biology and Biotechnology, The Healthy Lifespan Institute, Sheffield, UK
- The Institute of Neuroscience, University of Sheffield, Sheffield, UK
| | - Cleide Dos Santos Souza
- University of Sheffield, Sheffield Institute for Translational Neuroscience (SITraN), Sheffield, UK
| | - Sherif F El-Khamisy
- Department of Molecular Biology and Biotechnology, The Healthy Lifespan Institute, Sheffield, UK.
- The Institute of Neuroscience, University of Sheffield, Sheffield, UK.
- The Institute of Cancer Therapeutics, West Yorkshire, UK.
| | - Laura Ferraiuolo
- University of Sheffield, Sheffield Institute for Translational Neuroscience (SITraN), Sheffield, UK.
- The Institute of Neuroscience, University of Sheffield, Sheffield, UK.
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Kisby GE, Eriksen JL, Chlebowski AC, Spencer PS. Cycad Genotoxin Methylazoxymethanol Disrupts the Brain Ubiquitin-Proteasome Pathway, Tau and α-Synuclein, as Reported in ALS-PDC. J Neuropathol Exp Neurol 2021; 80:286-288. [PMID: 33550390 PMCID: PMC8786491 DOI: 10.1093/jnen/nlab006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Affiliation(s)
- Glen E Kisby
- Pharmacology, Western University for Health Sciences, Lebanon, Oregon, USA
| | | | - Anna C Chlebowski
- Pharmacology, Western University for Health Sciences, Lebanon, Oregon, USA
| | - Peter S Spencer
- Neurology, School of Medicine and Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon, USA
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11
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Western Pacific ALS-PDC: Evidence implicating cycad genotoxins. J Neurol Sci 2020; 419:117185. [PMID: 33190068 DOI: 10.1016/j.jns.2020.117185] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 09/20/2020] [Accepted: 09/29/2020] [Indexed: 12/12/2022]
Abstract
Amyotrophic Lateral Sclerosis and Parkinsonism-Dementia Complex (ALS-PDC) is a disappearing neurodegenerative disorder of apparent environmental origin formerly hyperendemic among Chamorros of Guam-USA, Japanese residents of the Kii Peninsula, Honshu Island, Japan and Auyu-Jakai linguistic groups of Papua-Indonesia on the island of New Guinea. The most plausible etiology is exposure to genotoxins in seed of neurotoxic cycad plants formerly used for food and/or medicine. Primary suspicion falls on methylazoxymethanol (MAM), the aglycone of cycasin and on the non-protein amino acid β-N-methylamino-L-alanine, both of which are metabolized to formaldehyde. Human and animal studies suggest: (a) exposures occurred early in life and sometimes during late fetal brain development, (b) clinical expression of neurodegenerative disease appeared years or decades later, and (c) pathological changes in various tissues indicate the disease was not confined to the CNS. Experimental evidence points to toxic molecular mechanisms involving DNA damage, epigenetic changes, transcriptional mutagenesis, neuronal cell-cycle reactivation and perturbation of the ubiquitin-proteasome system that led to polyproteinopathy and culminated in neuronal degeneration. Lessons learned from research on ALS-PDC include: (a) familial disease may reflect common toxic exposures across generations, (b) primary disease prevention follows cessation of exposure to culpable environmental triggers; and (c) disease latency provides a prolonged period during which to intervene therapeutically. Exposure to genotoxic chemicals ("slow toxins") in the early stages of life should be considered in the search for the etiology of ALS-PDC-related neurodegenerative disorders, including sporadic forms of ALS, progressive supranuclear palsy and Alzheimer's disease.
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12
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Armon C. From Snow to Hill to ALS: An epidemiological odyssey in search of ALS causation. J Neurol Sci 2018; 391:134-140. [DOI: 10.1016/j.jns.2018.05.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 04/19/2018] [Accepted: 05/19/2018] [Indexed: 12/11/2022]
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Kokubo Y, Banack SA, Morimoto S, Murayama S, Togashi T, Metcalf JS, Cox PA, Kuzuhara S. β-N-methylamino-l-alanine analysis in the brains of patients with Kii ALS/PDC. Neurology 2017; 89:1091-1092. [PMID: 28794246 DOI: 10.1212/wnl.0000000000004310] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Accepted: 05/30/2017] [Indexed: 11/15/2022] Open
Affiliation(s)
- Yasumasa Kokubo
- From the Kii ALS/PDC Research Center (Y.K.), Graduate School of Regional Innovation Studies and Department of Oncologic Pathology (S.M.), Mie University, Tsu, Japan; Brain Chemistry Labs (S.A.B., J.S.M., P.A.C.), Institute for Ethnomedicine, Jackson, WY; Tokyo Metropolitan Geriatric Hospital (S.M.); Marine Biosystems Research Center (T.T.), Chiba University; and Suzuka University of Medical Science (S.K.), Japan.
| | - Sandra Anne Banack
- From the Kii ALS/PDC Research Center (Y.K.), Graduate School of Regional Innovation Studies and Department of Oncologic Pathology (S.M.), Mie University, Tsu, Japan; Brain Chemistry Labs (S.A.B., J.S.M., P.A.C.), Institute for Ethnomedicine, Jackson, WY; Tokyo Metropolitan Geriatric Hospital (S.M.); Marine Biosystems Research Center (T.T.), Chiba University; and Suzuka University of Medical Science (S.K.), Japan
| | - Satoru Morimoto
- From the Kii ALS/PDC Research Center (Y.K.), Graduate School of Regional Innovation Studies and Department of Oncologic Pathology (S.M.), Mie University, Tsu, Japan; Brain Chemistry Labs (S.A.B., J.S.M., P.A.C.), Institute for Ethnomedicine, Jackson, WY; Tokyo Metropolitan Geriatric Hospital (S.M.); Marine Biosystems Research Center (T.T.), Chiba University; and Suzuka University of Medical Science (S.K.), Japan
| | - Shigeo Murayama
- From the Kii ALS/PDC Research Center (Y.K.), Graduate School of Regional Innovation Studies and Department of Oncologic Pathology (S.M.), Mie University, Tsu, Japan; Brain Chemistry Labs (S.A.B., J.S.M., P.A.C.), Institute for Ethnomedicine, Jackson, WY; Tokyo Metropolitan Geriatric Hospital (S.M.); Marine Biosystems Research Center (T.T.), Chiba University; and Suzuka University of Medical Science (S.K.), Japan
| | - Tatsuya Togashi
- From the Kii ALS/PDC Research Center (Y.K.), Graduate School of Regional Innovation Studies and Department of Oncologic Pathology (S.M.), Mie University, Tsu, Japan; Brain Chemistry Labs (S.A.B., J.S.M., P.A.C.), Institute for Ethnomedicine, Jackson, WY; Tokyo Metropolitan Geriatric Hospital (S.M.); Marine Biosystems Research Center (T.T.), Chiba University; and Suzuka University of Medical Science (S.K.), Japan
| | - James S Metcalf
- From the Kii ALS/PDC Research Center (Y.K.), Graduate School of Regional Innovation Studies and Department of Oncologic Pathology (S.M.), Mie University, Tsu, Japan; Brain Chemistry Labs (S.A.B., J.S.M., P.A.C.), Institute for Ethnomedicine, Jackson, WY; Tokyo Metropolitan Geriatric Hospital (S.M.); Marine Biosystems Research Center (T.T.), Chiba University; and Suzuka University of Medical Science (S.K.), Japan
| | - Paul Alan Cox
- From the Kii ALS/PDC Research Center (Y.K.), Graduate School of Regional Innovation Studies and Department of Oncologic Pathology (S.M.), Mie University, Tsu, Japan; Brain Chemistry Labs (S.A.B., J.S.M., P.A.C.), Institute for Ethnomedicine, Jackson, WY; Tokyo Metropolitan Geriatric Hospital (S.M.); Marine Biosystems Research Center (T.T.), Chiba University; and Suzuka University of Medical Science (S.K.), Japan
| | - Shigeki Kuzuhara
- From the Kii ALS/PDC Research Center (Y.K.), Graduate School of Regional Innovation Studies and Department of Oncologic Pathology (S.M.), Mie University, Tsu, Japan; Brain Chemistry Labs (S.A.B., J.S.M., P.A.C.), Institute for Ethnomedicine, Jackson, WY; Tokyo Metropolitan Geriatric Hospital (S.M.); Marine Biosystems Research Center (T.T.), Chiba University; and Suzuka University of Medical Science (S.K.), Japan
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Potjewyd G, Day PJ, Shangula S, Margison GP, Povey AC. L-β-N-methylamino-l-alanine (BMAA) nitrosation generates a cytotoxic DNA damaging alkylating agent: An unexplored mechanism for neurodegenerative disease. Neurotoxicology 2017; 59:105-109. [PMID: 28163087 DOI: 10.1016/j.neuro.2017.01.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 01/26/2017] [Accepted: 01/26/2017] [Indexed: 10/20/2022]
Abstract
BACKGROUND L-β-N-methylamino-l-alanine (BMAA) is a non-proteinic amino acid, that is neurotoxic in vitro and in animals, and is implicated in the causation of amyotrophic lateral sclerosis and parkinsonism-dementia complex (ALS-PDC) on Guam. Given that natural amino acids can be N-nitrosated to form toxic alkylating agents and the structural similarity of BMAA to other amino acids, our hypothesis was that N-nitrosation of BMAA might result in a toxic alkylating agent, providing a novel mechanistic hypothesis for BMAA action. FINDINGS We have chemically nitrosated BMAA with sodium nitrite to produce nitrosated BMAA (N-BMAA) which was shown to react with the alkyl-trapping agent, 4-(p-nitrobenzyl)pyridine, cause DNA strand breaks in vitro and was toxic to the human neuroblastoma cell line SH-SY5Y under conditions in which BMAA itself was minimally toxic. CONCLUSIONS Our results indicate that N-BMAA is an alkylating agent and toxin suggesting a plausible and previously unrecognised mechanism for the neurotoxic effects of BMAA.
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Affiliation(s)
- G Potjewyd
- Centre for Epidemiology, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - P J Day
- Centre for Epidemiology, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK; Manchester Institute for Biotechnology, University of Manchester, Manchester, UK
| | - S Shangula
- Centre for Epidemiology, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - G P Margison
- Centre for Epidemiology, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - A C Povey
- Centre for Epidemiology, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
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15
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Seeking environmental causes of neurodegenerative disease and envisioning primary prevention. Neurotoxicology 2016; 56:269-283. [DOI: 10.1016/j.neuro.2016.03.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 03/23/2016] [Indexed: 12/12/2022]
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16
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Hemeryck LY, Vanhaecke L. Diet-related DNA adduct formation in relation to carcinogenesis. Nutr Rev 2016; 74:475-89. [PMID: 27330144 DOI: 10.1093/nutrit/nuw017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The human diet contributes significantly to the initiation and promotion of carcinogenesis. It has become clear that the human diet contains several groups of natural foodborne chemicals that are at least in part responsible for the genotoxic, mutagenic, and carcinogenic potential of certain foodstuffs. Electrophilic chemicals are prone to attack nucleophilic sites in DNA, resulting in the formation of altered nucleobases, also known as DNA adducts. Since DNA adduct formation is believed to signal the onset of chemically induced carcinogenesis, the DNA adduct-inducing potential of certain foodstuffs has been investigated to gain more insight into diet-related pathways of carcinogenesis. Many studies have investigated diet-related DNA adduct formation. This review summarizes work on known or suspected dietary carcinogens and the role of DNA adduct formation in hypothesized carcinogenesis pathways.
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Affiliation(s)
- Lieselot Y Hemeryck
- L.Y. Hemeryck and L. Vanhaecke are with the Laboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Lynn Vanhaecke
- L.Y. Hemeryck and L. Vanhaecke are with the Laboratory of Chemical Analysis, Department of Veterinary Public Health and Food Safety, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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17
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Armon C. Accrued somatic mutations (nucleic acid changes) trigger ALS: 2005-2015 update. Muscle Nerve 2016; 53:842-9. [PMID: 26799358 DOI: 10.1002/mus.25049] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2016] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a multilevel disease of the motor neuron system. The mechanisms triggering disease onset should be considered separately from those facilitating its spread and motor neuron death. In 2005, I brought together clinical and epidemiological evidence to support the hypothesis that acquired nucleic acid changes may trigger sporadic ALS. Since 2005, the conceptual foundations for this hypothesis have been strengthened. The journal Amyotrophic Lateral Sclerosis was renamed Amyotrophic Lateral Sclerosis & Frontotemporal Degeneration. The focal onset, with simultaneous initial maximal upper and lower motor neuron involvement in the region of onset, and patterns of spread, were characterized further. Clues from the epidemiology of sporadic ALS were affirmed by quantitative analysis, including the increase in disease incidence with age, suggesting accrual of time-dependent changes, and the confirmation of smoking as an established risk factor. Additional observations support the conclusion that accrued somatic mutations trigger onset of ALS. Muscle Nerve 53: 842-849, 2016.
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Affiliation(s)
- Carmel Armon
- Tel Aviv University Sackler Faculty of Medicine and Assaf Harofeh Medical Center, Israel
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18
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Brown PL, Shepard PD, Elmer GI, Stockman S, McFarland R, Mayo CL, Cadet JL, Krasnova IN, Greenwald M, Schoonover C, Vogel MW. Altered spatial learning, cortical plasticity and hippocampal anatomy in a neurodevelopmental model of schizophrenia-related endophenotypes. Eur J Neurosci 2012; 36:2773-81. [PMID: 22762562 DOI: 10.1111/j.1460-9568.2012.08204.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Adult rats exposed to the DNA-methylating agent methylazoxymethanol on embryonic day 17 show a pattern of neurobiological deficits that model some of the neuropathological and behavioral changes observed in schizophrenia. Although it is generally assumed that these changes reflect targeted disruption of embryonic neurogenesis, it is unknown whether these effects generalise to other antimitotic agents administered at different stages of development. In the present study, neurochemical, behavioral and electrophysiological techniques were used to determine whether exposure to the antimitotic agent Ara-C later in development recapitulates some of the changes observed in methylazoxymethanol (MAM)-treated animals and in patients with schizophrenia. Male rats exposed to Ara-C (30 mg/kg/day) at embryonic days 19.5 and 20.5 show reduced cell numbers and heterotopias in hippocampal CA1 and CA2/3 regions, respectively, as well as cell loss in the superficial layers of the pre- and infralimbic cortex. Birth date labeling with bromodeoxyuridine reveals that the cytoarchitectural changes in CA2/3 are a consequence rather that a direct result of disrupted cortical neurogenesis. Ara-C-treated rats possess elevated levels of cortical dopamine and DOPAC (3,4-didyhydroxypheylacetic acid) but no change in norepinephrine or serotonin. Ara-C-treated rats are impaired in their ability to learn the Morris water maze task and showed diminished synaptic plasticity in the hippocampocortical pathway. These data indicate that disruption of neurogenesis at embryonic days 19.5 and 20.5 constitutes a useful model for the comparative study of deficits observed in other gestational models and their relationship to cognitive changes observed in schizophrenia.
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Affiliation(s)
- P Leon Brown
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, USA
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Ferguson D, Crowe M, McLaughlin L, Gaschen F. Survival and prognostic indicators for cycad intoxication in dogs. J Vet Intern Med 2011; 25:831-7. [PMID: 21777288 DOI: 10.1111/j.1939-1676.2011.00755.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Cycad palms are commonly used in landscaping and ingestion by dogs can cause disease or death. OBJECTIVES Determine the morbidity and case fatality of cycad palm toxicosis in dogs from Louisiana, and examine putative prognostic factors. ANIMALS Thirty-four client-owned dogs with confirmed cycad palm toxicosis between 2003 and 2010. METHODS Retrospective cohort study. Search of all medical records for animals with cycad palm toxicosis. RESULTS Seventeen of 34 (50%) dogs died or were euthanized as a direct consequence of cycad intoxication. There were no differences in presenting signs and physical examination findings between survivors and nonsurvivors. Nonsurvivors had higher serum alanine transaminase activity (median 196 U/L; range 16-4,123 versus 113.5; 48-1,530) and total bilirubin concentration (0.5 mg/dL; 0.1-6.2 versus 0.25; 0-1.7) upon presentation, and their initial serum concentrations of albumin (2.9 g/dL; 1.4-4.1 versus 3.3; 2.2-3.9) were lower than those of survivors. Nadir serum albumin concentration was also lower in nonsurvivors (1.9; 1.4-3.7 versus 3.2; 1.8-3.5). A higher proportion of nonsurvivors had prolonged coagulation times, prothrombin time. and partial thromboplastin time. In a multivariate model, administration of charcoal at initial presentation was associated with longer survival (heart rate [HR] 0.019, 95% CI 0.001-0.644), while high serum aspartate aminotransferase activity was a negative prognostic factor (HR 118.2, 95% CI 2.89-4,826). CONCLUSIONS AND CLINICAL IMPORTANCE Cycad intoxication is associated with a higher case fatality than previously published. Several laboratory parameters might help differentiating potential nonsurvivors from survivors. Administration of charcoal as part of the emergency treatment appears to have a protective effect.
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Affiliation(s)
- D Ferguson
- Department of Veterinary Clinical Sciences, Louisiana State University School of Veterinary Medicine, Baton Rouge, LA 70803, USA
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20
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Is neurodegenerative disease a long-latency response to early-life genotoxin exposure? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2011; 8:3889-921. [PMID: 22073019 PMCID: PMC3210588 DOI: 10.3390/ijerph8103889] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 09/09/2011] [Accepted: 09/15/2011] [Indexed: 01/03/2023]
Abstract
Western Pacific amyotrophic lateral sclerosis and parkinsonism-dementia complex, a disappearing neurodegenerative disease linked to use of the neurotoxic cycad plant for food and/or medicine, is intensively studied because the neuropathology (tauopathy) is similar to that of Alzheimer's disease. Cycads contain neurotoxic and genotoxic principles, notably cycasin and methylazoxymethanol, the latter sharing chemical relations with nitrosamines, which are derived from nitrates and nitrites in preserved meats and fertilizers, and also used in the rubber and leather industries. This review includes new data that influence understanding of the neurobiological actions of cycad and related genotoxins and the putative mechanisms by which they might trigger neurodegenerative disease.
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The cycad genotoxin MAM modulates brain cellular pathways involved in neurodegenerative disease and cancer in a DNA damage-linked manner. PLoS One 2011; 6:e20911. [PMID: 21731631 PMCID: PMC3121718 DOI: 10.1371/journal.pone.0020911] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Accepted: 05/16/2011] [Indexed: 02/02/2023] Open
Abstract
Methylazoxymethanol (MAM), the genotoxic metabolite of the cycad azoxyglucoside cycasin, induces genetic alterations in bacteria, yeast, plants, insects and mammalian cells, but adult nerve cells are thought to be unaffected. We show that the brains of adult C57BL6 wild-type mice treated with a single systemic dose of MAM acetate display DNA damage (O6-methyldeoxyguanosine lesions, O6-mG) that remains constant up to 7 days post-treatment. By contrast, MAM-treated mice lacking a functional gene encoding the DNA repair enzyme O6-mG DNA methyltransferase (MGMT) showed elevated O6-mG DNA damage starting at 48 hours post-treatment. The DNA damage was linked to changes in the expression of genes in cell-signaling pathways associated with cancer, human neurodegenerative disease, and neurodevelopmental disorders. These data are consistent with the established developmental neurotoxic and carcinogenic properties of MAM in rodents. They also support the hypothesis that early-life exposure to MAM-glucoside (cycasin) has an etiological association with a declining, prototypical neurodegenerative disease seen in Guam, Japan, and New Guinea populations that formerly used the neurotoxic cycad plant for food or medicine, or both. These findings suggest environmental genotoxins, specifically MAM, target common pathways involved in neurodegeneration and cancer, the outcome depending on whether the cell can divide (cancer) or not (neurodegeneration). Exposure to MAM-related environmental genotoxins may have relevance to the etiology of related tauopathies, notably, Alzheimer's disease.
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22
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Parkinson-dementia complex and development of a new stable isotope dilution assay for BMAA detection in tissue. Toxicol Appl Pharmacol 2009; 240:180-8. [PMID: 19716838 DOI: 10.1016/j.taap.2009.06.025] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 06/17/2009] [Accepted: 06/18/2009] [Indexed: 01/19/2023]
Abstract
Beta-methylamino-L-alanine (BMAA) has been proposed as a global contributor to neurodegenerative diseases, including Parkinson-dementia complex (PDC) of Guam and Alzheimer's disease (AD). The literature on the effects of BMAA is conflicting with some but not all in vitro data supporting a neurotoxic action, and experimental animal data failing to replicate the pattern of neurodegeneration of these human diseases, even at very high exposures. Recently, BMAA has been reported in human brain from individuals afflicted with PDC or AD. Some of the BMAA in human tissue reportedly is freely extractable (free) while some is protein-associated and liberated by techniques that hydrolyze the peptide bond. The latter is especially intriguing since BMAA is a non-proteinogenic amino acid that has no known tRNA. We attempted to replicate these findings with techniques similar to those used by others; despite more than adequate sensitivity, we were unable to detect free BMAA. Recently, using a novel stable isotope dilution assay, we again were unable to detect free or protein-associated BMAA in human cerebrum. Here we review the development of our new assay for tissue detection of BMAA and show that we are able to detect free BMAA in liver but not cerebrum, nor do we detect any protein-associated BMAA in mice fed this amino acid. These studies demonstrate the importance of a sensitive and specific assay for tissue BMAA and seriously challenge the proposal that BMAA is accumulating in human brain.
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23
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Praline J, Corcia P. Genetica della sclerosi laterale amiotrofica. Neurologia 2008. [DOI: 10.1016/s1634-7072(08)70528-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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24
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Yang W, Woltjer RL, Sokal I, Pan C, Wang Y, Brodey M, Peskind ER, Leverenz JB, Zhang J, Perl DP, Galasko DR, Montine TJ. Quantitative proteomics identifies surfactant-resistant alpha-synuclein in cerebral cortex of Parkinsonism-dementia complex of Guam but not Alzheimer's disease or progressive supranuclear palsy. THE AMERICAN JOURNAL OF PATHOLOGY 2007; 171:993-1002. [PMID: 17675576 PMCID: PMC1959487 DOI: 10.2353/ajpath.2007.070015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Parkinsonism-dementia complex (PDC) remains a significant health burden to the Chamorro population. We tested the hypothesis that quantitative proteomics might provide fresh insight into this enigmatic illness by analyzing proteins resistant to surfactant extraction from patients with Alzheimer's disease (AD) or PDC and their matched controls using isobaric tags for relative and absolute quantification. In addition to the expected increase in abnormal frontal cortical Abeta peptides, tau, ubiquitin, and apolipoprotein E in AD, and tau in PDC, we identified alpha-synuclein (SNCA) as a major abnormal protein in PDC but not AD. We confirmed our isobaric tags for relative and absolute quantification findings by enzyme-linked immunosorbent assay in frontal and temporal cortices. We extended our assays to include a limited number of cases of progressive supranuclear palsy (PSP) and dementia with Lewy bodies; we observed increased abnormal tau but not SNCA in PSP, and abnormal SNCA in dementia with Lewy bodies that was quantitatively similar to PDC. Finally, soluble Abeta oligomers were selectively increased in AD but not PDC or PSP. These results show that frontal and temporal cortex in PDC is distinguished from AD and PSP by its accumulation of abnormal SNCA and suggest that PDC be considered a synucleinopathy as well as a tauopathy.
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Affiliation(s)
- Wan Yang
- Department of Pathology, University of Washington, Harborview Medical Center, Box 359791, Seattle, WA 98104, USA
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Abstract
An evidence-based review was undertaken of the literature published between 2002 and 2006 about sports, trauma and ALS in order to see if there were new data to modify the conclusions of a previous review (2003). The new data support the previous conclusions that physical activity and trauma are probably ("more likely than not") not risk factors for ALS (Level II conclusions). This review concludes also that the reports of an apparent excess of ALS in Italian soccer players likely reflect incorrect analysis of the data. The appearance of excess relies on accepting as valid estimation methods resulting in improbably low numbers of expected cases. A different method is proposed: it generates more plausible numbers of expected cases, compared to which there is no excess of total cases (Level C conclusion). A theoretical framework is developed to analyze the possible influence of a "healthy worker effect" on incidence of neurodegenerative diseases in cohorts of employed or formerly employed individuals. In lieu of theoretical speculations, data are needed to measure this effect, while controlling for known lifestyle factors and accounting for the effect of loss of competing causes of mortality.
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Affiliation(s)
- Carmel Armon
- Tufts University School of Medicine, Boston, MA, USA
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26
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Bassanini S, Hallene K, Battaglia G, Finardi A, Santaguida S, Cipolla M, Janigro D. Early cerebrovascular and parenchymal events following prenatal exposure to the putative neurotoxin methylazoxymethanol. Neurobiol Dis 2007; 26:481-95. [PMID: 17398107 PMCID: PMC3041024 DOI: 10.1016/j.nbd.2007.02.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2006] [Revised: 01/31/2007] [Accepted: 02/21/2007] [Indexed: 01/19/2023] Open
Abstract
One of the most common causes of neurological disabilities are malformations of cortical development (MCD). A useful animal model of MCD consists of prenatal exposure to methylazoxymethanol (MAM), resulting in a postnatal phenotype characterized by cytological aberrations reminiscent of human MCD. Although postnatal effects of MAM are likely a consequence of prenatal events, little is known on how the developing brain reacts to MAM. General assumption is the effects of prenatally administered MAM are short lived (24 h) and neuroblast-specific. MAM persisted for several days after exposure in utero in both maternal serum and fetal brain, but at levels lower than predicted by a neurotoxic action. MAM levels and time course were consistent with a different mechanism of indirect neuronal toxicity. The most prominent acute effects of MAM were cortical swelling associated with mild cortical disorganization and neurodegeneration occurring in absence of massive neuronal cell death. Delayed or aborted vasculogenesis was demonstrated by MAM's ability to hinder vessel formation. In vitro, MAM reduced synthesis and release of VEGF by endothelial cells. Decreased expression of VEGF, AQP1, and lectin-B was consistent with a vascular target in prenatal brain. The effects of MAM on cerebral blood vessels persisted postnatally, as indicated by capillary hypodensity in heterotopic areas of adult rat brain. In conclusion, these results show that MAM does not act only as a neurotoxin per se, but may additionally cause a short-lived toxic effect secondary to cerebrovascular dysfunction, possibly due to a direct anti-angiogenic effect of MAM itself.
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Affiliation(s)
- Stefania Bassanini
- Department of Cerebrovascular Research, Cleveland, OH, USA
- Department of Experimental Neurophysiology, Lab of Molecular Neuroanatomy, Neurological Institute “C. Besta”, Milano, Italy
| | - Kerri Hallene
- Department of Cerebrovascular Research, Cleveland, OH, USA
| | - Giorgio Battaglia
- Department of Experimental Neurophysiology, Lab of Molecular Neuroanatomy, Neurological Institute “C. Besta”, Milano, Italy
| | - Adele Finardi
- Department of Experimental Neurophysiology, Lab of Molecular Neuroanatomy, Neurological Institute “C. Besta”, Milano, Italy
| | | | - Marilyn Cipolla
- The University of Vermont College of Medicine, Burlington, VT, USA
| | - Damir Janigro
- Department of Cerebrovascular Research, Cleveland, OH, USA
- Department of Cell Biology, The Cleveland Clinic Foundation, Cleveland, OH, USA
- Department of Molecular Medicine, Cleveland, OH, USA
- Corresponding author. Molecular Medicine, Cleveland Clinic Foundation, NB-20 LRI, 9500 Euclid Ave, Cleveland, OH 44195, USA. Fax: +1 216 445 1466. (D. Janigro)
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27
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Mehl A, Schanke TM, Torvik A, Fonnum F. The effect of trichlorfon and methylazoxymethanol on the development of guinea pig cerebellum. Toxicol Appl Pharmacol 2007; 219:128-35. [PMID: 17150236 DOI: 10.1016/j.taap.2006.10.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Revised: 10/27/2006] [Accepted: 10/27/2006] [Indexed: 10/24/2022]
Abstract
The pesticide trichlorfon (125 mg/kg on days 42-44 in gestation) gives hypoplasia of the brain of the offspring without any significant reduction in their body weights. The hypoplasia may be caused by trichlorfon itself or by its metabolite dichlorvos. This period of development coincides with the growth spurt period of guinea pig brain. The largest changes occurred in the cerebellum. Electron microscopic examination of the cerebellar cortex showed increased apoptotic death of cells in the granule cell layer after trichlorfon treatment. A reduction in thickness of the external germinal layer of the cerebellar cortex and an elevated amount of pyknotic and karyorrhexic cells in the granule cell layer was found. There was a significant reduction in choline esterase, choline acetyltransferase and glutamate decarboxylase activities in the cerebellum. Methylazoxymethanol (15 mg/kg body weight, day 43) was examined for comparison and caused similar hypoplasia of the guinea pig cerebellum, but did also induce a reduction in body weight. Trichloroethanol, the main metabolite of trichlorfon, did not give brain hypoplasia.
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Affiliation(s)
- Anna Mehl
- Norwegian Defense Research Establishment, Division for Protection and Material, Kjeller, Norway
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Kisby GE, Olivas A, Standley M, Lu X, Pattee P, O’Malley J, Li X, Muniz J, Nagalla SR. Genotoxicants target distinct molecular networks in neonatal neurons. ENVIRONMENTAL HEALTH PERSPECTIVES 2006; 114:1703-12. [PMID: 17107856 PMCID: PMC1665395 DOI: 10.1289/ehp.9073] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
BACKGROUND Exposure of the brain to environmental agents during critical periods of neuronal development is considered a key factor underlying many neurologic disorders. OBJECTIVES In this study we examined the influence of genotoxicants on cerebellar function during early development by measuring global gene expression changes. METHODS We measured global gene expression in immature cerebellar neurons (i.e., granule cells) after treatment with two distinct alkylating agents, methylazoxymethanol (MAM) and nitrogen mustard (HN2). Granule cell cultures were treated for 24 hr with MAM (10-1,000 microM) or HN2 (0.1-20 microM) and examined for cell viability, DNA damage, and markers of apoptosis. RESULTS Neuronal viability was significantly reduced (p < 0.01) at concentrations > 500 microM for MAM and > 1.0 microM for HN2; this correlated with an increase in both DNA damage and markers of apoptosis. Neuronal cultures treated with sublethal concentrations of MAM (100 microM) or HN2 (1.0 microM) were then examined for gene expression using large-scale mouse cDNA microarrays (27,648). Gene expression results revealed that a) global gene expression was predominantly up-regulated by both genotoxicants; b) the number of down-regulated genes was approximately 3-fold greater for HN2 than for MAM; and c) distinct classes of molecules were influenced by MAM (i.e, neuronal differentiation, the stress and immune response, and signal transduction) and HN2 (i.e, protein synthesis and apoptosis). CONCLUSIONS These studies demonstrate that individual genotoxicants induce distinct gene expression signatures. Further study of these molecular networks may explain the variable response of the developing brain to different types of environmental genotoxicants.
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Affiliation(s)
- Glen E. Kisby
- Center for Research on Occupational and Environmental Toxicology (CROET), Oregon Health & Science University, Portland, Oregon
| | - Antoinette Olivas
- Center for Research on Occupational and Environmental Toxicology (CROET), Oregon Health & Science University, Portland, Oregon
| | - Melissa Standley
- Department of Pediatrics, School of Medicine, Oregon Health & Science University, Portland, Oregon
| | - Xinfang Lu
- Department of Pediatrics, School of Medicine, Oregon Health & Science University, Portland, Oregon
| | - Patrick Pattee
- Department of Pediatrics, School of Medicine, Oregon Health & Science University, Portland, Oregon
| | - Jean O’Malley
- Department of Pediatrics, School of Medicine, Oregon Health & Science University, Portland, Oregon
| | - Xiaorong Li
- Center for Research on Occupational and Environmental Toxicology (CROET), Oregon Health & Science University, Portland, Oregon
| | - Juan Muniz
- Center for Research on Occupational and Environmental Toxicology (CROET), Oregon Health & Science University, Portland, Oregon
| | - Srinavasa R. Nagalla
- Department of Pediatrics, School of Medicine, Oregon Health & Science University, Portland, Oregon
- Address correspondence to S. Nagalla, Department of Pediatrics, School of Medicine, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd., Portland, OR 97239 USA. Telephone: (503) 494-1928. Fax: (503) 494-4821. E-mail:
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Winton MJ, Joyce S, Zhukareva V, Practico D, Perl DP, Galasko D, Craig U, Trojanowski JQ, Lee VMY. Characterization of tau pathologies in gray and white matter of Guam parkinsonism-dementia complex. Acta Neuropathol 2006; 111:401-12. [PMID: 16609851 DOI: 10.1007/s00401-006-0053-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Revised: 02/05/2006] [Accepted: 02/05/2006] [Indexed: 10/24/2022]
Abstract
Guam parkinsonism-dementia complex (PDC) is a neurodegenerative tauopathy in ethnic Chamorro residents of the Mariana Islands that manifests clinically with parkinsonism as well as dementia and is characterized neuropathologically by prominent cortical neuron loss in association with extensive telencephalic neurofibrillary tau pathology. To further characterize cortical gray and white matter tau, alpha-synuclein and lipid peroxidation pathologies in Guam PDC, we examined the brains of 17 Chamorro PDC and control subjects using biochemical and immunohistological techniques. We observed insoluble tau pathology in both gray and white matter of PDC and Guam control cases, with frontal and temporal lobes being most severely affected. Using phosphorylation dependent anti-tau antibodies, abundant tau inclusions were detected by immunohistochemistry in both neuronal and glial cells of the neocortex, while less alpha-synuclein pathology was observed in more limited brain regions. Further, in sharp contrast to Alzheimer's disease (AD), levels of the lipid peroxidation product 8, 12-iso-iPF(2alpha)-VI isoprostane were not elevated in Guam PDC brains relative to controls. Thus, although the tau pathologies of Guam PDC share similarities with AD, the composite Guam PDC neuropathology profile of tau, alpha-synuclein and 8, 12-iso-iPF(2alpha)-VI isoprostane reported here more closely resembles that seen in other tauopathies including frontotemporal dementias (FTDs), which may imply that Guam PDC and FTD tauopathies share underlying mechanisms of neurodegeneration.
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Affiliation(s)
- Matthew J Winton
- The Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-4283, USA
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Gros-Louis F, Gaspar C, Rouleau GA. Genetics of familial and sporadic amyotrophic lateral sclerosis. Biochim Biophys Acta Mol Basis Dis 2006; 1762:956-72. [PMID: 16503123 DOI: 10.1016/j.bbadis.2006.01.004] [Citation(s) in RCA: 177] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Revised: 01/12/2006] [Accepted: 01/17/2006] [Indexed: 12/11/2022]
Abstract
Diseases affecting motor neurons, such as amyotrophic lateral sclerosis (Lou Gerhig's disease), hereditary spastic paraplegia and spinal bulbar muscular atrophy (Kennedy's disease) are a heterogeneous group of chronic progressive diseases and are among the most puzzling yet untreatable illnesses. Over the last decade, identification of mutations in genes predisposing to these disorders has provided the means to better understand their pathogenesis. The discovery 13 years ago of SOD1 mutations linked to ALS, which account for less than 2% of total cases, had a major impact in the field. However, despite intensive research effort, the pathways leading to the specific motor neurons degeneration in the presence of SOD1 mutations have not been fully identified. This review provides an overview of the genetics of both familial and sporadic forms of ALS.
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Affiliation(s)
- Francois Gros-Louis
- Center for the Study of Brain Diseases, CHUM Research Center, Notre Dame Hospital, J.A. de Sève Pavillion, Room Y-3633, 1560, Sherbrooke Street East, Montreal, QC, Canada H2L 4M1
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Stipa G, Taiuti R, de Scisciolo G, Arnetoli G, Tredici MR, Biondi N, Barsanti L, Lolli F. Sporadic amyotrophic lateral sclerosis as an infectious disease: A possible role of cyanobacteria? Med Hypotheses 2006; 67:1363-71. [PMID: 16890380 DOI: 10.1016/j.mehy.2006.04.070] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Accepted: 04/06/2006] [Indexed: 12/14/2022]
Abstract
The available epidemiological data for amyotrophic lateral sclerosis (ALS) support an infectious etiology and lead us to propose a new hypothesis. We examined older epidemiological data concerning categories of the population with increased incidence (aged people, people living in rural areas, farmers, breeders), more recent epidemiological reports regarding Italian soccer players, AIDS patients, people living in highly polluted areas, and reports of cases of conjugal and pregnancy-associated ALS. The toxic and infectious hypotheses lead us to suggest a role for cyanobacteria in the production of endogenous beta-N-methylamino-L-alanine. Infection from a cyanobacterium, or another ubiquitous bacterium having similar characteristics, may be the missing clue to the etiology of ALS. We speculate that ubiquitous bacteria secreting toxic amino acids and "colonizing" tissues and organs in the human body might be the common element linking motor neuron diseases in Guam to sporadic ALS in the rest of the world.
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Affiliation(s)
- Giuseppe Stipa
- Dipartimento di Scienze Neurologiche e Psichiatriche, Università degli Studi di Firenze, and Neurofisiopatologia-Unità Spinale, Azienda Ospedaliero Universitaria Careggi, Italy
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Abstract
This article brings together evidence to support the hypothesis that acquired nucleic acid changes are the proximate causes, "triggers," or "initiators" of sporadic amyotrophic lateral sclerosis (ALS). Clinical features that support this hypothesis include focal onset and spread, and the individualized rate of progression. Clues from the epidemiology of sporadic ALS include the increase in its incidence with age, suggesting accrual of time-dependent changes, and the emergence of smoking, a known carcinogen, as its first "more likely than not" exogenous risk factor. The identification of any exogenous risk factor suggests that a large proportion of sporadic cases have a triggering mechanism susceptible to that factor. Ingestion of the products of cycad circinalis has been hypothesized to be implicated in causing Western Pacific ALS. Cycad contains both neurotoxic factors and carcinogens. The dissimilarity of Western Pacific ALS from neurotoxic diseases suggests a greater likelihood that the effects of DNA alkylation are its proximate cause.
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Affiliation(s)
- Carmel Armon
- Division of Neurology, Baystate Medical Center, Springfield, Massachusetts 01199, USA.
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Ince PG, Codd GA. Return of the cycad hypothesis - does the amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC) of Guam have new implications for global health? Neuropathol Appl Neurobiol 2005; 31:345-53. [PMID: 16008818 DOI: 10.1111/j.1365-2990.2005.00686.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recently published work provides evidence in support of the cycad hypothesis for Lytico--Bodig, the Guamanian amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC), based on a new understanding of Chamorro food practices, a cyanobacterial origin of beta-methylaminoalanine (BMAA) in cycad tissue, and a possible mechanism of biomagnification of this neurotoxic amino acid in the food chain. BMAA is one of two cycad chemicals with known neurotoxic properties (the other is cycasin, a proven developmental neurotoxin) among the many substances that exist in these highly poisonous plants, the seeds of which are used by Chamorros for food and medicine. The traditional diet includes the fruit bat, a species that feeds on cycad seed components and reportedly bioaccumulates BMAA. Plant and animal proteins provide a previously unrecognized reservoir for the slow release of this toxin. BMAA is reported in the brain tissue of Guam patients and early data suggest that some Northern American patients dying of Alzheimer's disease (AD) have detectable brain levels of BMAA. The possible role of cyanobacterial toxicity in sporadic neurodegenerative disease is therefore worthy of consideration. Recent neuropathology studies of ALS/PDC confirm understanding of this disorder as a 'tangle' disease, based on variable anatomical burden, and showing biochemical characteristics of 'AD-like' combined 3R and 4R tau species. This model mirrors the emerging view that other neurodegenerative disease spectra comprise clusters of related syndromes, owing to common molecular pathology, with variable anatomical distribution in the nervous system giving rise to different clinical phenotypes. Evidence for 'ubiquitin-only' inclusions in ALS/PDC is weak. Similarly, although there is evidence for alpha-synucleinopathy in ALS/PDC, the parkinsonian component of the disease is not caused by Lewy body disease. The spectrum of sporadic AD includes involvement of the substantia nigra and a high prevalence of 'incidental'alpha-synucleinopathy in sporadic AD is reported. Therefore the pathogenesis of Lytico-Bodig appears still to have most pertinence to the ongoing investigation of the pathogenesis of AD and other tauopathies.
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Affiliation(s)
- P G Ince
- Academic Unit of Pathology, Division of Genomic Medicine, University of Sheffield, Sheffield, UK.
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Kisby GE, Standley M, Lu X, O'Malley J, Lin B, Muniz J, Luo NL, Pattee P, Back SA, Nagalla SR. Molecular networks perturbed in a developmental animal model of brain injury. Neurobiol Dis 2005; 19:108-18. [PMID: 15837566 DOI: 10.1016/j.nbd.2004.11.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2004] [Revised: 11/16/2004] [Accepted: 11/23/2004] [Indexed: 11/29/2022] Open
Abstract
Methylazoxymethanol (MAM) is widely used as a developmental neurotoxin and exposure to its glucoside (i.e., cycasin) is associated with the prototypical neurological disorder western Pacific ALS/PDC. However, the specific molecular targets that play a key role in MAM-induced brain injury remain unclear. To reveal potential molecular networks targeted by MAM in the developing nervous system, we examined characteristic phenotypic changes (DNA damage, cytoarchitecture) induced by MAM and their correlation with gene expression differences using microarray assays (27,648 genes). Three day-old postnatal C57BL/6 mice (PND3) received a single injection of MAM and the cerebellum and cerebral cortex of PND4, 8, 15, and 22 mice were analyzed. DNA damage was detected in both the cerebellum (N7-mGua, TUNEL labeling) and cerebral cortex (N7-mGua) of PND4 mice, but progressive disruption of the cytoarchitecture was restricted to the cerebellum. A majority (>75%) of the genes affected (cerebellum 636 genes, cortex 1080 genes) by MAM were developmentally regulated, with a predominant response early (PND4) in the cerebellum and delayed (PND8 and 15) in the cerebral cortex. The genes and pathways (e.g., proteasome) affected by MAM in the cerebellum are distinct from cortex. The genes perturbed in the cerebellum reflect critical cellular processes such as development (17%), cell cycle (7%), protein metabolism (12%), and transcriptional regulation (9%) that could contribute to the observed cytoarchitectural disruption of the cerebellum. This study demonstrates for the first time that specific genes and molecular networks are affected by MAM during CNS development. Further investigation of these targets will help to understand how disruption of these developmental programs could contribute to chronic brain injury or neurodegenerative disease.
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Affiliation(s)
- G E Kisby
- Center for Research on Occupational and Environmental Toxicology (CROET), Portland, OR 97239, USA
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Kleven GA, Queral L, Robinson SR. Prenatal methylazoxymethanol exposure alters evoked responses in fetal rats. Neurotoxicol Teratol 2004; 26:663-71. [PMID: 15315815 DOI: 10.1016/j.ntt.2004.06.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2004] [Revised: 06/07/2004] [Accepted: 06/10/2004] [Indexed: 11/28/2022]
Abstract
Although there is considerable interest in identifying methods to detect central nervous system impairment early in development, few behavioral assessment tools are available for detecting CNS deficits in the fetus. In the present study, methylazoxymethanol [MAM; Midwest Research Institute, (MRI)] was used to induce deficits in CNS development in fetal rats to assess effects on coordinated fetal behavior. Fetuses were exposed by administering MAM to pregnant rats on E17 of gestation via intraperitoneal injection and then were prepared for behavioral testing 3 days later on E20. After externalization from the uterus into a warm saline bath, fetal subjects received either an intraoral infusion of lemon extract to evoke a facial wiping response or were presented with an artificial nipple to evoke an oral grasping response. Interlimb coordination and paw-face contact during facial wiping were disrupted in MAM-exposed fetuses. Similarly, MAM exposure diminished the ability of fetuses to grasp or maintain oral contact with the artificial nipple. Although clear disruptions of movement coordination were seen in the MAM-treated subjects, there were no significant differences from saline controls in weight or anatomical measures. Together, these findings suggest that behavioral assessments of fetal motor coordination may be useful in identifying neural insult during prenatal development.
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Affiliation(s)
- Gale A Kleven
- Department of Psychology, University of Iowa, E11 Seashore Hall, Iowa City, IA 52242, USA.
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Jongen-Rêlo AL, Leng A, Lüber M, Pothuizen HHJ, Weber L, Feldon J. The prenatal methylazoxymethanol acetate treatment: a neurodevelopmental animal model for schizophrenia? Behav Brain Res 2004; 149:159-81. [PMID: 15129780 DOI: 10.1016/s0166-4328(03)00228-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The prenatal methylazoxymethanol acetate (MAM) treatment has been proposed as a suitable model for the neurodevelopmental aspects of schizophrenia since the morphological abnormalities it induces in the brain are subtle and in line with most reports of neuropathology in schizophrenic brains. However, the functional aspects of this treatment have not been investigated with behavioural paradigms that are relevant for the psychopathology of the symptoms of schizophrenia. In the present study, we investigated the validity of the prenatal MAM treatment as a developmental model for schizophrenia with a prepulse inhibition of the acoustic startle reflex, latent inhibition, locomotor activity, and cognition and emotionality with freezing in fear conditioning paradigms. We have conducted two studies: in Study I, MAM was injected from E09 to E12, and in Study II MAM was administered at later stages in the embryonic development, from E12 to E15. Morphologically, the prenatal MAM treatment induced mild to severe reduction in brain weights and in the entorhinal cortex, prefrontal cortex and striatum volumes, the severity of the effects depending on the timing of administration. However, despite the morphological abnormalities induced by the MAM treatments, no behavioural deficits were observed in the MAM-treated animals when compared to Controls in prepulse inhibition, latent inhibition with the two-way active avoidance, and in the freezing paradigms. Therefore, due to the consistent lack of treatment effect observed in the present investigation, we conclude that the prenatal MAM treatment has no validity as a behavioural model for schizophrenia.
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Affiliation(s)
- Ana L Jongen-Rêlo
- Behavioural Neurobiology Laboratory, Swiss Federal Institute of Technology, Zurich, Schorenstrasse 16, CH-8603 Schwerzenbach, Switzerland
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Fonnum F, Lock EA. The contributions of excitotoxicity, glutathione depletion and DNA repair in chemically induced injury to neurones: exemplified with toxic effects on cerebellar granule cells. J Neurochem 2004; 88:513-31. [PMID: 14720201 DOI: 10.1046/j.1471-4159.2003.02211.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Six chemicals, 2-halopropionic acids, thiophene, methylhalides, methylmercury, methylazoxymethanol (MAM) and trichlorfon (Fig. 1), that cause selective necrosis to the cerebellum, in particular to cerebellar granule cells, have been reviewed. The basis for the selective toxicity to these neurones is not fully understood, but mechanisms known to contribute to the neuronal cell death are discussed. All six compounds decrease cerebral glutathione (GSH), due to conjugation with the xenobiotic, thereby reducing cellular antioxidant status and making the cells more vulnerable to reactive oxygen species. 2-Halopropionic acids and methylmercury appear to also act via an excitotoxic mechanism leading to elevated intracellular Ca2+, increased reactive oxygen species and ultimately impaired mitochondrial function. In contrast, the methylhalides, trichlorfon and MAM all methylate DNA and inhibit O6-guanine-DNA methyltransferase (OGMT), an important DNA repair enzyme. We propose that a combination of reduced antioxidant status plus excitotoxicity or DNA damage is required to cause cerebellar neuronal cell death with these chemicals. The small size of cerebellar granule cells, the unique subunit composition of their N-methyl-d-aspartate (NMDA) receptors, their low DNA repair ability, low levels of calcium-binding proteins and vulnerability during postnatal brain development and distribution of glutathione and its conjugating and metabolizing enzymes are all important factors in determining the sensitivity of cerebellar granule cells to toxic compounds.
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Affiliation(s)
- F Fonnum
- Norwegian Defence Research Establishment, Division for Protection and Material, Kjeller, Norway.
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Abstract
Abstract
This chapter focuses on amyotrophic lateral sclerosis (ALS), the most common motor neuron disease. It discusses the three major forms of ALS: sporadic ALS, the familial or hereditary form of ALS, and the western Pacific (Mariana Islands) form. Considerable progress has been made in recent years on identifying genetic loci responsible for Mendelian forms of ALS; this evidence is summarized. The potential importance of geographic clusters is discussed, with particular emphasis on the western Pacific form of ALS because it often occurs in association with a parkinsonism and/or dementia complex (PDC). The incidence of Western Pacific ALS peaked and then declined in the mid-20th century, which strongly implicated an environmental cause. The chapter also presents detailed information regarding putative risk factors for sporadic ALS, which includes environmental toxicants, skeletal trauma, cigarette smoking, diet, and vigorous physical activity.
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Shaw CA, Wilson JMB. Analysis of neurological disease in four dimensions: insight from ALS-PDC epidemiology and animal models. Neurosci Biobehav Rev 2003; 27:493-505. [PMID: 14599431 DOI: 10.1016/j.neubiorev.2003.08.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The causal factor(s) responsible for sporadic neurological diseases are unknown and the stages of disease progression remain undefined and poorly understood. We have developed an animal model of amyotrophic lateral sclerosis-parkinsonism dementia complex which mimics all the essential features of the disease with the initial neurological insult arising from neurotoxins contained in washed cycad seeds. Animals fed washed cycad develop deficits in motor, cognitive, and sensory behaviors that correlate with the loss of neurons in specific regions of the central nervous system. The ability to recreate the disease by exposure to cycad allows us to extend the model in multiple dimensions by analyzing behavioral, cellular, and biochemical changes over time. In addition, the ability to induce toxin-based neurodegeneration allows us to probe the interactions between genetic and epigenetic factors. Our results show that the impact of both genetic causal and susceptibility factors with the cycad neurotoxins are complex. The article describes the features of the model and suggests ways that our understanding of cycad-induced neurodegeneration can be used to decipher and identify the early events in various human neurological diseases.
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Affiliation(s)
- C A Shaw
- Program in Neuroscience, University of British Columbia, Vancouver, BC, Canada.
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Abstract
Once thought to be a single pathological disease state, amyotrophic lateral sclerosis (ALS) is now recognized to be the limited phenotypic expression of a complex, heterogeneous group of biological processes, resulting in an unrelenting loss of motor neurons. On average, individuals affected with the disease live <5 years. In this article, the complex nature of the pathogenesis of ALS, including features of age dependency, environmental associations, and genetics, is reviewed. Once held to be uncommon, it is now clear that ALS is associated with a frontotemporal dementia and that this process may reflect disturbances in the microtubule-associated tau protein metabolism. The motor neuron ultimately succumbs in a state where significant disruptions in neurofilament metabolism, mitochondrial function, and management of oxidative stress exist. The microenvironment of the neuron becomes a complex milieu in which high levels of glutamate provide a source of chronic excitatory neurotoxicity, and the contributions of activated microglial cells lead to further cascades of motor neuron death, perhaps serving to propagate the disease once established. The final process of motor neuron death encompasses many features of apoptosis, but it is clear that this alone cannot account for all features of motor neuron loss and that aspects of a necrosis-apoptosis continuum are at play. Designing pharmacological strategies to mitigate against this process thus becomes an increasingly complex issue, which is reviewed in this article.
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Affiliation(s)
- Michael J Strong
- Department of Clinical Neurological Sciences, Robarts Research Institute, Room 7OF 10, University Campus, London Health Sciences Centre, University of Western Ontario, 339 Windermere Road, London, Ontario, Canada N6A 5A5.
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Abstract
Amyotrophic lateral sclerosis (ALS) is a late onset, rapidly progressive and ultimately fatal neurological disorder, caused by the loss of motor neurons in the brain and spinal cord. Familial aggregation of ALS, with an age-dependent but high penetrance, is a major risk factor for ALS. Familial ALS (FALS) is clinically and genetically heterogeneous. Three genes and linkage to four additional gene loci have been identified so far and may either predominantly lead to ALS (ALSI-ALS6) or cause multisystem neurodegeneration with ALS as an occasional symptom (tauopathies, ALS-dementia complex). This review presents a tentative classification of the "major" ALS genes and ALS "susceptibility" genes, that may act as susceptibility factors for neurodegeneration in interaction with other genetic or environmental risk factors. Considering that mutations in ALS genes explain approximately 10% of familial as well as sporadic ALS, and most remaining cases of the discase are thought to result form the interaction of several genes and environmental factors, ALS is a paradigm for multifactorial discases.
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Affiliation(s)
- D Majoor-Krakauer
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, the Netherlands.
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Chapter 7 Epidemiology of Amyotrophic Lateral Sclerosis/Motor Neuron Disease. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1877-3419(09)70108-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Trojanowski JQ, Ishihara T, Higuchi M, Yoshiyama Y, Hong M, Zhang B, Forman MS, Zhukareva V, Lee VMY. Amyotrophic lateral sclerosis/parkinsonism dementia complex: transgenic mice provide insights into mechanisms underlying a common tauopathy in an ethnic minority on Guam. Exp Neurol 2002; 176:1-11. [PMID: 12093078 DOI: 10.1006/exnr.2002.7940] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Intracytoplasmic filamentous tau inclusions are neuropathological hallmarks of amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) of Guam and the defining lesions of other neurodegenerative disorders known as tauopathies. Here we review current insights into the cell and molecular neuropathology of ALS/PDC, a common tauopathy in the Chamorro population on Guam. We also summarize recent advances in understanding this disorder through studies of transgenic (Tg) mouse models of this tauopathy. Briefly, overexpression of human tau isoforms in the central nervous system of Tg mice resulted in a neurodegenerative tauopathy with a phenotype similar to ALS/PDC. Specifically, argyrophilic, congophilic, and tau immunoreactive inclusions accumulated with age in cortical and brainstem neurons of these mice, but they were most abundant in spinal cord neurons, and the inclusions contained 10- to 20-nm tau-positive straight filaments. There also was extensive gliosis in spinal cord associated with axonal degeneration in the ventral roots, while remaining axons in spinal nerves showed a loss of microtubules and reduced fast axonal transport. With advancing age, these Tg mice showed increasing motor weakness, and this was accompanied by a progressive increase in the phosphorylation and insolubility of brain and spinal cord tau proteins. Thus, tau Tg mice recapitulate key phenotypic features of ALS/PDC neuropathology in an ethnic minority on Guam, and these animal models provide new opportunities to discover novel therapies for this and related tauopathies.
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Affiliation(s)
- John Q Trojanowski
- The Center for Neurodegenerative Disease Research, The University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA
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Battu S, Elyaman W, Hugon J, Cardot PJ. Cortical cell elution by sedimentation field-flow fractionation. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1528:89-96. [PMID: 11687294 DOI: 10.1016/s0304-4165(01)00174-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
As a cell sorter, Sedimentation field-flow fractionation (SdFFF) can be defined as an effective tool for cell separation and purification, respecting integrity and viability as well as providing enhanced recovery and purified sterile fraction collection. The complex cell suspension containing both neurons and glial cells of all types, obtained from cerebral cortices of 17-day-old rat fetuses, is routinely used as a model of primary neuronal culture. Using SdFFF, this complex cell mixture was eluted in sterile fractions which were collected and cultured. SdFFF cell elution was conducted under strictly defined conditions: rapid cell elution, high recovery (negligible cell trapping), short- and long-term cell viability, sterile collection. After immunological cellular type characterization (neurons and glial cells) of cultured cells, our results demonstrated the effectiveness of SdFFF to provide, in less than 6 min, viable and enriched neurons which can be cultured for further investigations.
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Affiliation(s)
- S Battu
- Laboratoire de Chimie Analytique et Bromatologie, Faculté de Pharmacie, Université de Limoges, France.
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Hugon J, Esclaire F, Lesort M, Kisby G, Spencer P. Toxic neuronal apoptosis and modifications of tau and APP gene and protein expressions. Drug Metab Rev 1999; 31:635-47. [PMID: 10461544 DOI: 10.1081/dmr-100101939] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The causes and the mechanisms of neuronal death in Alzheimer's disease are not elucidated, although some new insights have been proposed over the past years, including free-radical toxicity, beta-amyloid toxicity, excitotoxicity, and disturbed cellular calcium metabolism. Some authors have also pointed out that apoptosis could play a role in neuronal degeneration, but it is still largely debated. Here, we review some recent data linking the induction of experimental neuronal apoptosis in vitro and the molecular pathology of the tau protein and amyloid precursor protein (APP). In cultures exposed to mild glutamate toxicity, tau mRNA expression, not beta-actin, is enhanced in stressed neurons. The Guam cycad toxin metabolite methylazoxymethanol also produces an increase of tau gene transcription that exacerbates changes induced by glutamate. In serum-deprived cultures or glutamate-exposed cultures, neurons committed to apoptosis have a reduced tau gene expression, whereas resistant neurons display a stable or even augmented tau mRNA expression accompanied by a persistent tau phosphorylation near serine 202. In the same conditions, stressed neurons produce membrane blebbings strongly immunopositive for APP and putative amyloidogenic fragments that are subsequently released in the extracellular space. Experimental apoptosis in neurons can recapitulate tau and APP modifications that could be associated with a selective vulnerability and a progression of cellular degeneration along the neuronal network.
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Affiliation(s)
- J Hugon
- Department of Histology and Cell Biology, Faculty of Medicine, University of Limoges, France.
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Abstract
It is generally agreed that ALS/PDC is triggered by a disappearing environmental factor peculiar to the lifestyle of people of the western Pacific (i.e., Guam, Irian Jaya, Indonesia, and the Kii Peninsula of Japan). A strong candidate is the cycad plant genotoxin cycasin, the beta-D-glucoside of methylazoxymethanol (MAM). We propose that prenatal or postnatal exposure to low levels of cycasin/MAM may damage neuronal DNA, compromise DNA repair, perturb neuronal gene expression, and irreversibly alter cell function to precipitate a slowly evolving disease ("slow-toxin" hypothesis). In support of our hypothesis, we have demonstrated the following: 1. DNA from postmitotic rodent central nervous system neurons is particularly sensitive to damage by MAM. 2. MAM reduces DNA repair in human and rodent neurons, whereas DNA-repair inhibitors potentiate MAM-induced DNA damage and toxicity in mature rodent nervous tissue. 3. Human neurons (SY5Y neuroblastoma) that are deficient in DNA repair are susceptible to MAM-induced cytotoxicity and DNA damage, whereas overexpression of DNA repair in similar cells is protective. 4. MAM alters gene expression in SY5Y human neuroblastoma cells and, in the presence of DNA damage and reduced DNA repair, enhances glutamate-modulated expression of tau mRNA in rat primary neurons; the corresponding protein (TAU) is elevated in ALS/PDC and Alzheimer's disease. These findings support a direct relationship between MAM-induced DNA damage and neurotoxicity and suggest the genotoxin may operate in a similar manner in vivo. More broadly, a combination of genotoxin-induced DNA damage (via exogenous and/or endogenous agents) and disturbed DNA repair may be important contributing factors in the slow and progressive degeneration of neurons that is characteristic of sporadic neurodegenerative disease. Preliminary studies demonstrate that DNA repair is reduced in the brain of subjects with western Pacific ALS/PDC, ALS, and Alzheimer's disease, which would increase the susceptibility of brain tissue to DNA damage by endogenous/exogenous genotoxins. Interindividual differences in the extent of prior exposure to DNA-damaging agents and/or the efficiency of its repair might produce population variety in the rate of damage accumulation and explain the susceptibility of certain individuals to sporadic neurodegenerative disease. Studies are underway using DNA-repair proficient and deficient neuronal cell cultures and mutant mice to explore gene-environment interplay with respect to MAM treatment, DNA damage, and DNA repair, and the age-related appearance of neurobehavioral and neuropathological compromise.
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Affiliation(s)
- G E Kisby
- Center for Research on Occupational and Environmental Toxicology, School of Medicine, Oregon Health Sciences University, Portland 97201, USA.
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Tor-Agbidye J, Palmer VS, Spencer PS, Craig AM, Blythe LL, Sabri MI. Sodium cyanate alters glutathione homeostasis in rodent brain: relationship to neurodegenerative diseases in protein-deficient malnourished populations in Africa. Brain Res 1999; 820:12-9. [PMID: 10023026 DOI: 10.1016/s0006-8993(98)01343-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Sodium cyanate, a neurotoxic chemical in rodents, primates and humans, is implicated in neurodegenerative disorders in protein-deficient populations subsisting in parts of Africa on the cyanogenic plant cassava. The molecular and cellular mechanisms of cyanate neurotoxicity are not understood. This study investigates the effect of sodium cyanate on glutathione (GSH) homeostasis in rodent brain and liver in vitro and in vivo. GSH levels in mouse brain were rapidly, time- and dose-dependently decreased following intraperitoneal administration of 100, 200 or 300 mg/kg sodium cyanate. By contrast, GSH disulfide (GSSG) levels were increased and GSH/GSSG ratios were decreased in a dose-dependent manner in rat brain. Sodium cyanate depleted GSH levels in all regions of mouse brain. Brain glutathione reductase activity was dose-dependently inhibited, while glutathione peroxidase activity was not affected by sodium cyanate. The disruption of GSH homeotasis, as evidenced by reduced tissue GSH/GSSG ratios, likely results from cyanate-induced inhibition of glutathione reductase activity. The results of this study suggest that cyanate neurotoxicity, and perhaps cassava-associated neurodegenerative diseases, are mediated in part by disruption of glutathione homeostasis in neural tissue.
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Affiliation(s)
- J Tor-Agbidye
- Center for Research on Occupational and Environmental Toxicology, L606, Oregon Health Sciences University, 3181 S.W. Sam Jackson Park Road, Portland, 97201-3098 OR, USA
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