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Emerick GL, da Silva Lima V, Costa BF, Nakamura VHDS, Lentz DV, Bonache JS, Ehrich M. Human blood markers of cholinergic neurotoxicity and neuropathy: A useful guide for laboratory applications. Neurotoxicology 2024; 101:16-25. [PMID: 38224782 DOI: 10.1016/j.neuro.2024.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 01/01/2024] [Accepted: 01/09/2024] [Indexed: 01/17/2024]
Abstract
Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are useful markers to assess the effects of exposure to anticholinesterase insecticides (Anti-AChE). In addition, lymphocyte neuropathy target esterase (LNTE) has been used as biomarker of neuropathic organophosphate compounds (OPs). Thus, this study evaluates the main types of circulating biomarkers related to the cholinergic system and to the neuropathy induced by OPs in standardized human samples. To achieve this objective, total protein of human plasma, erythrocytes and lymphocytes were first standardized, and then AChE, BChE and LNTE activities in human blood were evaluated in the presence of inhibitors. The acceptance criteria of the regulatory agency were respected with coefficients of regression of curves of 0.9972 for cholinesterase and 0.9956 for LNTE analyses. The wavelength established to perform cholinesterase assay was 450 nm and the time of incubation of the enzymes with inhibitors was 30 min. Differences were observed among the IC50 values regarding the in vitro inhibition of AChE, BChE and LNTE in the presence of OPs. In conclusion, the procedures demonstrated by the present work were simple, fast, inexpensive, sensitive, easy to be replicated and suitable to make conclusions about the neurotoxicity induced by Anti-AChE and neuropathic OPs.
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Affiliation(s)
- Guilherme Luz Emerick
- Instituto de Ciências da Saúde, Universidade Federal de Mato Grosso - ICS/CUS/UFMT - Sinop, MT, Brazil.
| | - Valfran da Silva Lima
- Instituto de Ciências da Saúde, Universidade Federal de Mato Grosso - ICS/CUS/UFMT - Sinop, MT, Brazil
| | - Bruna Francisquete Costa
- Instituto de Ciências da Saúde, Universidade Federal de Mato Grosso - ICS/CUS/UFMT - Sinop, MT, Brazil
| | | | - Dayana Veruska Lentz
- Instituto de Ciências da Saúde, Universidade Federal de Mato Grosso - ICS/CUS/UFMT - Sinop, MT, Brazil
| | - Juliandra Spagnol Bonache
- Instituto de Ciências da Saúde, Universidade Federal de Mato Grosso - ICS/CUS/UFMT - Sinop, MT, Brazil
| | - Marion Ehrich
- Department of Biomedical Science and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Blacksburg, VA, USA
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Torres-Sánchez ED, Ortiz GG, Reyes-Uribe E, Torres-Jasso JH, Salazar-Flores J. Effect of pesticides on phosphorylation of tau protein, and its influence on Alzheimer's disease. World J Clin Cases 2023; 11:5628-5642. [PMID: 37727721 PMCID: PMC10506003 DOI: 10.12998/wjcc.v11.i24.5628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 07/17/2023] [Accepted: 08/08/2023] [Indexed: 08/24/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive and neurodegenerative illness which results in alterations in cognitive development. It is characterized by loss/dysfunction of cholinergic neurons, and formation of amyloid plaques, and formation of neurofibrillary tangles, among other changes, due to hyperphosphorylation of tau-protein. Exposure to pesticides in humans occurs frequently due to contact with contaminated food, water, or particles. Organochlorines, organophosphates, carbamates, pyrethroids and neonicotinoids are associated with the most diagnosed incidents of severe cognitive impairment. The aim of this study was to determine the effects of these pesticides on the phosphorylation of tau protein, and its cognitive implications in the development of AD. It was found that exposure to pesticides increased the phosphorylation of tau protein at sites Ser198, Ser199, Ser202, Thr205, Ser396 and Ser404. Contact with these chemicals altered the enzymatic activities of cyclin-dependent kinase 5 and glycogen synthase kinase 3 beta, and protein phosphatase-2A. Moreover, it altered the expression of the microtubule associated protein tau gene, and changed levels of intracellular calcium. These changes affected tau protein phosphorylation and neuroinflammation, and also increased oxidative stress. In addition, the exposed subjects had poor level of performance in tests that involved evaluation of novelty, as test on verbal, non-verbal, spatial memory, attention, and problem-solving skills.
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Affiliation(s)
- Erandis D Torres-Sánchez
- Department of Medical and Life Sciences, University Center of la Cienega, University of Guadalajara, Ocotlan 47820, Jalisco, Mexico
| | - Genaro G Ortiz
- Department of Philosophical and Methodological Disciplines and Service of Molecular Biology in Medicine Hospital Civil, University of Guadalajara, Guadalajara 44340, Jalisco, Mexico
| | - Emmanuel Reyes-Uribe
- Department of Medical and Life Sciences, University Center of la Cienega, University of Guadalajara, Ocotlan 47820, Jalisco, Mexico
| | - Juan H Torres-Jasso
- Department of Biological Sciences, CUCOSTA, University of Guadalajara, Puerto Vallarta 48280, Jalisco, Mexico
| | - Joel Salazar-Flores
- Department of Medical and Life Sciences, University Center of la Cienega, University of Guadalajara, Ocotlan 47820, Jalisco, Mexico
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3
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The phospholipase A 2 superfamily as a central hub of bioactive lipids and beyond. Pharmacol Ther 2023; 244:108382. [PMID: 36918102 DOI: 10.1016/j.pharmthera.2023.108382] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 03/13/2023]
Abstract
In essence, "phospholipase A2" (PLA2) means a group of enzymes that release fatty acids and lysophospholipids by hydrolyzing the sn-2 position of glycerophospholipids. To date, more than 50 enzymes possessing PLA2 or related lipid-metabolizing activities have been identified in mammals, and these are subdivided into several families in terms of their structures, catalytic mechanisms, tissue/cellular localizations, and evolutionary relationships. From a general viewpoint, the PLA2 superfamily has mainly been implicated in signal transduction, driving the production of a wide variety of bioactive lipid mediators. However, a growing body of evidence indicates that PLA2s also contribute to phospholipid remodeling or recycling for membrane homeostasis, fatty acid β-oxidation for energy production, and barrier lipid formation on the body surface. Accordingly, PLA2 enzymes are considered one of the key regulators of a broad range of lipid metabolism, and perturbation of specific PLA2-driven lipid pathways often disrupts tissue and cellular homeostasis and may be associated with a variety of diseases. This review covers current understanding of the physiological functions of the PLA2 superfamily, focusing particularly on the two major intracellular PLA2 families (Ca2+-dependent cytosolic PLA2s and Ca2+-independent patatin-like PLA2s) as well as other PLA2 families, based on studies using gene-manipulated mice and human diseases in combination with comprehensive lipidomics.
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4
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Countermeasures in organophosphorus intoxication: pitfalls and prospects. Trends Pharmacol Sci 2022; 43:593-606. [DOI: 10.1016/j.tips.2022.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 04/14/2022] [Accepted: 04/17/2022] [Indexed: 11/24/2022]
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PNPLA6/NTE, an Evolutionary Conserved Phospholipase Linked to a Group of Complex Human Diseases. Metabolites 2022; 12:metabo12040284. [PMID: 35448471 PMCID: PMC9025805 DOI: 10.3390/metabo12040284] [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: 02/24/2022] [Revised: 03/18/2022] [Accepted: 03/22/2022] [Indexed: 12/27/2022] Open
Abstract
Patatin-like phospholipase domain-containing protein 6 (PNPLA6), originally called Neuropathy Target Esterase (NTE), belongs to a family of hydrolases with at least eight members in mammals. PNPLA6/NTE was first identified as a key factor in Organophosphate-induced delayed neuropathy, a degenerative syndrome that occurs after exposure to organophosphates found in pesticides and nerve agents. More recently, mutations in PNPLA6/NTE have been linked with a number of inherited diseases with diverse clinical symptoms that include spastic paraplegia, ataxia, and chorioretinal dystrophy. A conditional knockout of PNPLA6/NTE in the mouse brain results in age-related neurodegeneration, whereas a complete knockout causes lethality during embryogenesis due to defects in the development of the placenta. PNPLA6/NTE is an evolutionarily conserved protein that in Drosophila is called Swiss-Cheese (SWS). Loss of SWS in the fly also leads to locomotory defects and neuronal degeneration that progressively worsen with age. This review will describe the identification of PNPLA6/NTE, its expression pattern, and normal role in lipid homeostasis, as well as the consequences of altered NPLA6/NTE function in both model systems and patients.
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Knoll-Gellida A, Dubrana LE, Bourcier LM, Mercé T, Gruel G, Soares M, Babin PJ. Hyperactivity and Seizure Induced by Tricresyl Phosphate Are Isomer Specific and Not Linked to Phenyl Valerate-Neuropathy Target Esterase Activity Inhibition in Zebrafish. Toxicol Sci 2021; 180:160-174. [DOI: 10.1093/toxsci/kfab006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Abstract
Environmental exposure to tricresyl phosphate (TCP) may lead to severe neurotoxic effects, including organophosphate (OP)-induced delayed neuropathy. TCP has three symmetric isomers, distinguished by the methyl group position on the aromatic ring system. One of these isomers, tri-ortho-cresyl phosphate (ToCP), has been reported for years as a neuropathic OP, targeting neuropathic target esterase (NTE/PNPLA6), but its mode of toxic action had not been fully elucidated. Zebrafish eleuthero-embryo and larva were used to characterize the differential action of the TCP isomers. The symmetric isomers inhibited phenyl valerate (PV)-NTE enzymatic activity in vivo with different IC50, while no effect was observed on acetylcholinesterase activity. Moreover, the locomotor behavior was also affected by tri-para-cresyl phosphate and tri-meta-cresyl phosphate, only ToCP exposure led to locomotor hyperactivity lasting several hours, associated with defects in the postural control system and an impaired phototactic response, as revealed by the visual motor response test. The electric field pulse motor response test demonstrated that a seizure-like, multiple C-bend-spaghetti phenotype may be significantly induced by ToCP only, independently of any inhibition of PV-NTE activity. Eleuthero-embryos exposed to picrotoxin, a known gamma-aminobutyric acid type-A receptor inhibitor, exhibited similar adverse outcomes to ToCP exposure. Thus, our results demonstrated that the TCP mode of toxic action was isomer specific and not initially related to modulation of PV-NTE activity. Furthermore, it was suggested that the molecular events involved were linked to an impairment of the balance between excitation and inhibition in neuronal circuits.
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Affiliation(s)
- Anja Knoll-Gellida
- Department of Life and Health Sciences, INSERM, Maladies Rares: Génétique et Métabolisme (MRGM), U1211, Université de Bordeaux, F-33615 Pessac, France
| | - Leslie E Dubrana
- Department of Life and Health Sciences, INSERM, Maladies Rares: Génétique et Métabolisme (MRGM), U1211, Université de Bordeaux, F-33615 Pessac, France
| | - Laure M Bourcier
- Department of Life and Health Sciences, INSERM, Maladies Rares: Génétique et Métabolisme (MRGM), U1211, Université de Bordeaux, F-33615 Pessac, France
| | - Théo Mercé
- Department of Life and Health Sciences, INSERM, Maladies Rares: Génétique et Métabolisme (MRGM), U1211, Université de Bordeaux, F-33615 Pessac, France
| | - Gaëlle Gruel
- Department of Life and Health Sciences, INSERM, Maladies Rares: Génétique et Métabolisme (MRGM), U1211, Université de Bordeaux, F-33615 Pessac, France
| | - Magalie Soares
- Department of Life and Health Sciences, INSERM, Maladies Rares: Génétique et Métabolisme (MRGM), U1211, Université de Bordeaux, F-33615 Pessac, France
| | - Patrick J Babin
- Department of Life and Health Sciences, INSERM, Maladies Rares: Génétique et Métabolisme (MRGM), U1211, Université de Bordeaux, F-33615 Pessac, France
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Luo F, Sandhu AF, Rungratanawanich W, Williams GE, Akbar M, Zhou S, Song BJ, Wang X. Melatonin and Autophagy in Aging-Related Neurodegenerative Diseases. Int J Mol Sci 2020; 21:ijms21197174. [PMID: 32998479 PMCID: PMC7584015 DOI: 10.3390/ijms21197174] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 09/21/2020] [Accepted: 09/22/2020] [Indexed: 02/06/2023] Open
Abstract
With aging, the nervous system gradually undergoes degeneration. Increased oxidative stress, endoplasmic reticulum stress, mitochondrial dysfunction, and cell death are considered to be common pathophysiological mechanisms of various neurodegenerative diseases (NDDs) such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), organophosphate-induced delayed neuropathy (OPIDN), and amyotrophic lateral sclerosis (ALS). Autophagy is a cellular basic metabolic process that degrades the aggregated or misfolded proteins and abnormal organelles in cells. The abnormal regulation of neuronal autophagy is accompanied by the accumulation and deposition of irregular proteins, leading to changes in neuron homeostasis and neurodegeneration. Autophagy exhibits both a protective mechanism and a damage pathway related to programmed cell death. Because of its "double-edged sword", autophagy plays an important role in neurological damage and NDDs including AD, PD, HD, OPIDN, and ALS. Melatonin is a neuroendocrine hormone mainly synthesized in the pineal gland and exhibits a wide range of biological functions, such as sleep control, regulating circadian rhythm, immune enhancement, metabolism regulation, antioxidant, anti-aging, and anti-tumor effects. It can prevent cell death, reduce inflammation, block calcium channels, etc. In this review, we briefly discuss the neuroprotective role of melatonin against various NDDs via regulating autophagy, which could be a new field for future translational research and clinical studies to discover preventive or therapeutic agents for many NDDs.
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Affiliation(s)
- Fang Luo
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (F.L.); (A.F.S.); (G.E.W.)
| | - Aaron F. Sandhu
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (F.L.); (A.F.S.); (G.E.W.)
| | - Wiramon Rungratanawanich
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA; (W.R.); (B.-J.S.)
| | - George E. Williams
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (F.L.); (A.F.S.); (G.E.W.)
| | - Mohammed Akbar
- Division of Neuroscience & Behavior, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA;
| | - Shuanhu Zhou
- Departments of Orthopedic Surgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA;
| | - Byoung-Joon Song
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA; (W.R.); (B.-J.S.)
| | - Xin Wang
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (F.L.); (A.F.S.); (G.E.W.)
- Correspondence:
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Liu C, Zhou W, Li Z, Ren J, Li X, Li S, Liu Q, Song F, Hao A, Wang F. Melatonin Protects Neural Stem Cells Against Tri-Ortho-Cresyl Phosphate-Induced Autophagy. Front Mol Neurosci 2020; 13:25. [PMID: 32210763 PMCID: PMC7069477 DOI: 10.3389/fnmol.2020.00025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 02/03/2020] [Indexed: 01/04/2023] Open
Abstract
Tri-ortho-cresyl phosphate (TOCP) is an extensively used organophosphate in industry. It has been proven to lead to toxicity in different organ systems, especially in the nervous system. Neural stem cells (NSCs) play important roles in both embryonic and adult nervous systems. However, whether TOCP induces cytotoxicity in embryonic NSCs remains unclear. In this study, mouse NSCs were exposed to different concentrations of TOCP for 24 h. The results showed that TOCP led to impaired proliferation of NSCs and induced the autophagy of NSCs by increasing the generation of intracellular reactive oxygen species (ROS) and decreasing the phosphorylation of extracellular regulated protein kinase (ERK1/2). Melatonin has been reported to exert neuroprotective effects via various mechanisms. Therefore, we further investigate whether melatonin has potential protective effects against TOCP-induced cytotoxicity on NSCs. Our data showed that melatonin pretreatment attenuated TOCP-induced autophagy by suppressing oxidative stress and restoring ERK1/2 phosphorylation consistently. Taken together, the results indicated that TOCP induced the autophagy in mouse NSCs, and melatonin may effectively protect NSCs against TOCP-induced autophagy.
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Affiliation(s)
- Chang Liu
- Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Key Laboratory of Mental Disorders, Department of Anatomy and Histoembryology, School of Basic Medical Sciences, Shandong University, Jinan, China
| | - Wenjuan Zhou
- Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Key Laboratory of Mental Disorders, Department of Anatomy and Histoembryology, School of Basic Medical Sciences, Shandong University, Jinan, China
| | - Zhaopei Li
- Department of Oncology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, China
| | - Jun Ren
- Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Key Laboratory of Mental Disorders, Department of Anatomy and Histoembryology, School of Basic Medical Sciences, Shandong University, Jinan, China
| | - Xian Li
- Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Key Laboratory of Mental Disorders, Department of Anatomy and Histoembryology, School of Basic Medical Sciences, Shandong University, Jinan, China
| | - Shan Li
- Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Key Laboratory of Mental Disorders, Department of Anatomy and Histoembryology, School of Basic Medical Sciences, Shandong University, Jinan, China
| | - Qian Liu
- Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Key Laboratory of Mental Disorders, Department of Anatomy and Histoembryology, School of Basic Medical Sciences, Shandong University, Jinan, China
| | - Fuyong Song
- Institute of Toxicology, School of Public Health, Shandong University, Jinan, China
| | - Aijun Hao
- Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Key Laboratory of Mental Disorders, Department of Anatomy and Histoembryology, School of Basic Medical Sciences, Shandong University, Jinan, China
| | - Fuwu Wang
- Key Laboratory for Experimental Teratology of Ministry of Education, Shandong Key Laboratory of Mental Disorders, Department of Anatomy and Histoembryology, School of Basic Medical Sciences, Shandong University, Jinan, China
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Tacroximes: novel unique compounds for the recovery of organophosphorus-inhibited acetylcholinesterase. Future Med Chem 2019; 11:2625-2634. [DOI: 10.4155/fmc-2019-0027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Aim: Organophosphorus compounds are irreversible inhibitors of AChE. Without immediate countermeasure, intoxication leads quickly to death. None of the clinically-used causal antidotes can ensure a good prognosis for any poisoned patient. When fallen into the wrong hands, organophosphates represent a serious threat to mankind. Results & methodology: Herein, we describe two novel compounds as unique merged molecules built on a tacrine scaffold against organophosphorus intoxication. These reactivators of AChE have balanced physicochemical properties, and should be able to cross the blood–brain barrier with a slightly lowered cytotoxicity profile compared to reference tacrine. Conclusion: Their efficiency compared with pralidoxime and obidoxime was proved against dichlorvos.
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Su H, Lin YP, Yang SC, Kuo CH, Wu DC, Shiea J, Lee CW. Rapid detection of non-volatile household pesticides in drained gastric juice by ambient mass spectrometry for emergency management. Anal Chim Acta 2019; 1066:69-78. [DOI: 10.1016/j.aca.2019.03.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/06/2019] [Accepted: 03/07/2019] [Indexed: 01/13/2023]
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Wang P, Yang M, Jiang L, Wu YJ. A fungicide miconazole ameliorates tri-o-cresyl phosphate-induced demyelination through inhibition of ErbB/Akt pathway. Neuropharmacology 2018; 148:31-39. [PMID: 30553827 DOI: 10.1016/j.neuropharm.2018.12.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 11/21/2018] [Accepted: 12/12/2018] [Indexed: 12/21/2022]
Abstract
Organophosphorus compound (OP)-induced delayed neuropathy (OPIDN) is characterized by distal axonal degeneration and demyelination of the central and peripheral axons, which leads to progressive muscle weakness, ataxia and paralysis in several days after OP intoxication. This study aimed to investigate the possible use of an imidazole fungicide miconazole as a novel therapy for OPIDN. Adult hens, the most commonly used animal models in OPIDN studies, were orally given tri-o-cresyl phosphate (TOCP). We showed that miconazole, which was administered daily to hens beginning on the 7th day after TOCP exposure, drastically ameliorated the neurotoxic symptoms and histopathological damages in spinal cord and sciatic nerves. Mechanistically, miconazole inhibited the TOCP-induced activation of ErbB/Akt signaling, and enhanced the myelin basic protein (MBP) expression. In a glial cell model sNF96.2 cells, miconazole restored the TOCP-inhibited MBP expression, and promoted cell differentiation as well as cell migration by inhibiting the activation of ErbB/Akt signaling pathway. In sum, miconazole, a synthetic imidazole fungicide, could ameliorate the symptoms and histopathological changes of OPIDN, probably by promoting glial cell differentiation and migration to enhance myelination via inhibiting the activation of ErbB/Akt. Thus, miconazole is a promising candidate therapy for the clinical treatment of OPIDN.
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Affiliation(s)
- Pan Wang
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1-5 Beichenxilu Road, Beijing, 100101, China
| | - Min Yang
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1-5 Beichenxilu Road, Beijing, 100101, China
| | - Lu Jiang
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1-5 Beichenxilu Road, Beijing, 100101, China
| | - Yi-Jun Wu
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1-5 Beichenxilu Road, Beijing, 100101, China.
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12
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The Antidiabetic Drug Liraglutide Minimizes the Non-Cholinergic Neurotoxicity of the Pesticide Mipafox in SH-SY5Y Cells. Neurotox Res 2018; 35:150-159. [PMID: 30088187 DOI: 10.1007/s12640-018-9941-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 07/24/2018] [Accepted: 07/31/2018] [Indexed: 12/14/2022]
Abstract
Organophosphorus (OPs) compounds have been widely used in agriculture, industry, and household, and the neurotoxicity induced by them is still a cause of concern. The main toxic mechanism of OPs is the inhibition of acetylcholinesterase (AChE); however, the delayed neuropathy induced by OPs (OPIDN) is mediated by other mechanisms such as the irreversible inhibition of 70% of NTE activity (neuropathy target esterase) that leads to axonal degeneration. Liraglutide is a long-lasting GLP-1 analog clinically used as antidiabetic. Its neurotrophic and neuroprotective effects have been demonstrated in vitro and in experimental models of neurodegenerative diseases. As in OPIDN, axonal degeneration also plays a role in neurodegenerative diseases. Therefore, this study investigated the protective potential of liraglutide against the neurotoxicity of OPs by using mipafox as a neuropathic agent (at a concentration able to inhibit and age 70% of NTE activity) and a neuronal model with SH-SY5Y neuroblastoma cells, which express both esterases. Liraglutide protected cells against the neurotoxicity of mipafox by increasing neuritogenesis, the uptake of glucose, the levels of cytoskeleton proteins, and synaptic-plasticity modulators, besides decreasing the pro-inflammatory cytokine interleukin 1β and caspase-3 activity. This is the first study to suggest that liraglutide might induce beneficial effects against the delayed, non-cholinergic neurotoxicity of OPs.
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13
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Xu HY, Wang P, Sun YJ, Xu MY, Zhu L, Wu YJ. Activation of Neuregulin 1/ErbB Signaling Is Involved in the Development of TOCP-Induced Delayed Neuropathy. Front Mol Neurosci 2018; 11:129. [PMID: 29740279 PMCID: PMC5925568 DOI: 10.3389/fnmol.2018.00129] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 03/29/2018] [Indexed: 01/03/2023] Open
Abstract
Organophosphate-induced delayed neuropathy (OPIDN) is characterized by progressive axonal degeneration and demyelination of the spinal cord and sciatic nerves. The neuregulin 1/epidermal growth factor receptor (ErbB) signaling pathway is crucial for axonal myelination. In this study, we investigated whether the neuregulin 1/ErbB signaling pathway mediated the progression of OPIDN. Adult hens were given tri-o-cresyl phosphate (TOCP), a typical neuropathic organophosphorus compound, to induce OPIDN. The ErbB inhibitor lapatinib was administered to hens 4 h prior to and 4 days after TOCP exposure. The neuregulin 1/ErbB signaling pathway was examined for their role in maintaining spinal cord and sciatic nerve fiber integrity. Schwann cell line sNF96.2 was used as the in vitro cell model. The in vivo results showed that TOCP (750 mg/kg body weight, p.o.) induced prominent ataxia and significant axon degeneration in the spinal cord and sciatic nerves. Lapatinib (25 mg/kg body weight, p.o.) treatment attenuated OPIDN clinically and histopathlogically and partially prevented the TOCP-induced activation of neuregulin 1/ErbB signaling pathway. Lapatinib also prevented the TOCP-induced inhibition of neuropathy target esterase (NTE), a key enzyme during the development of OPIDN, and the disturbed metabolism of phosphatidylcholine in sciatic nerves. In addition, lapatinib was shown, in vitro, to protect sNF96.2 cells from TOCP-induced dedifferentiation through neuregulin 1/ErbB signaling. Our results suggest that neuregulin 1/ErbB, through regulation of NTE activity in the peripheral nervous system, mediates the progression of OPIDN. Thus, this signal may serve as a potential target for the treatment of OPIDN.
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Affiliation(s)
- Hai-Yang Xu
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Pan Wang
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Ying-Jian Sun
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Department of Veterinary Medicine and Animal Science, Beijing University of Agriculture, Beijing, China
| | - Ming-Yuan Xu
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Li Zhu
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Yi-Jun Wu
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
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14
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Faria M, Fuertes I, Prats E, Abad JL, Padrós F, Gomez-Canela C, Casas J, Estevez J, Vilanova E, Piña B, Raldúa D. Analysis of the neurotoxic effects of neuropathic organophosphorus compounds in adult zebrafish. Sci Rep 2018; 8:4844. [PMID: 29555973 PMCID: PMC5859099 DOI: 10.1038/s41598-018-22977-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 03/05/2018] [Indexed: 12/13/2022] Open
Abstract
Inhibition and aging of neuropathy target esterase (NTE) by exposure to neuropathic organophosphorus compounds (OPs) can result in OP-induced delayed neuropathy (OPIDN). In the present study we aimed to build a model of OPIDN in adult zebrafish. First, inhibition and aging of zebrafish NTE activity were characterized in the brain by using the prototypic neuropathic compounds cresyl saligenin phosphate (CBDP) and diisopropylphosphorofluoridate (DFP). Our results show that, as in other animal models, zebrafish NTE is inhibited and aged by both neuropathic OPs. Then, a neuropathic concentration inhibiting NTE activity by at least 70% for at least 24 h was selected for each compound to analyze changes in phosphatidylcholines (PCs), lysophosphatidylcholines (LPCs) and glycerolphosphocholine (GPC) profiles. In spite to the strong inhibition of the NTE activity found for both compounds, only a mild increase in the LPCs level was found after 48 h of the exposure to DFP, and no effect were observed by CBDP. Moreover, histopathological evaluation and motor function outcome analyses failed to find any neurological abnormalities in the exposed fish. Thus, our results strongly suggest that zebrafish is not a suitable species for the development of an experimental model of human OPIDN.
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Affiliation(s)
- Melissa Faria
- Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, E-08034, Barcelona, Spain
| | - Inmaculada Fuertes
- Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, E-08034, Barcelona, Spain
| | - Eva Prats
- CID-CSIC, Jordi Girona 18, E-08034, Barcelona, Spain
| | - Jose Luis Abad
- Department of Biomedicinal Chemistry, Institute for Advanced Chemistry of Catalonia, (IQAC-CSIC), Jordi Girona 18, E-08034, Barcelona, Spain
| | - Francesc Padrós
- Fish Diseases Diagnostic Service, Facultat de Veterinaria Universitat Autònoma de Barcelona, 08190, Bellaterra (Cerdanyola del Vallès), Spain
| | - Cristian Gomez-Canela
- Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, E-08034, Barcelona, Spain
| | - Josefina Casas
- Department of Biomedicinal Chemistry, Institute for Advanced Chemistry of Catalonia, (IQAC-CSIC), Jordi Girona 18, E-08034, Barcelona, Spain
| | - Jorge Estevez
- Institute of Bioengineering, University "Miguel Hernandez" of Elche, Alicante, Spain
| | - Eugenio Vilanova
- Institute of Bioengineering, University "Miguel Hernandez" of Elche, Alicante, Spain
| | - Benjamin Piña
- Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, E-08034, Barcelona, Spain
| | - Demetrio Raldúa
- Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, E-08034, Barcelona, Spain.
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15
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Fernandes LS, Dos Santos NAG, Emerick GL, Santos ACD. L- and T-type calcium channel blockers protect against the inhibitory effects of mipafox on neurite outgrowth and plasticity-related proteins in SH-SY5Y cells. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2017; 80:1086-1097. [PMID: 28862523 DOI: 10.1080/15287394.2017.1357359] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Some organophosphorus compounds (OP), including the pesticide mipafox, produce late onset distal axonal degeneration, known as organophosphorus-induced delayed neuropathy (OPIDN). The underlying mechanism involves irreversible inhibition of neuropathy target esterase (NTE) activity, elevated intracellular calcium levels, increased activity of calcium-activated proteases and impaired neuritogenesis. Voltage-gated calcium channels (VGCC) appear to play a role in several neurologic disorders, including OPIDN. Therefore, this study aimed to examine and compare the neuroprotective effects of T-type (amiloride) and L-type (nimodipine) VGCC blockers induced by the inhibitory actions of mipafox on neurite outgrowth and axonal proteins of retinoic-acid-stimulated SH-SY5Y human neuroblastoma cells, a neuronal model widely employed to determine the neurotoxicity attributed to OP. Both nimodipine and amiloride significantly blocked augmentation of intracellular calcium levels and activity of calpains, as well as decreased neurite length, number of differentiated cells, and lowered concentrations of growth-associated protein 43 (GAP-43) and synapsin induced by mipafox. Only nimodipine inhibited reduction of synaptophysin levels produced by mipafox. These findings demonstrate a role for calcium and VGCC in the impairment of neuronal plasticity mediated by mipafox. Data also demonstrated the neuroprotective potential of T-type and L-type VGCC blockers to inhibit OP-mediated actions, which may be beneficial to counteract cases of pesticide poisoning.
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Affiliation(s)
- Laís Silva Fernandes
- a Departamento de Análises Clínicas , Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto - FCFRP - USP , Ribeirão Preto , SP , Brazil
| | - Neife Aparecida G Dos Santos
- a Departamento de Análises Clínicas , Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto - FCFRP - USP , Ribeirão Preto , SP , Brazil
| | - Guilherme Luz Emerick
- b Instituto de Ciências da Saúde, Universidade Federal de Mato Grosso - ICS/UFMT/CUS , Sinop , MT , Brazil
| | - Antonio Cardozo Dos Santos
- a Departamento de Análises Clínicas , Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto - FCFRP - USP , Ribeirão Preto , SP , Brazil
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16
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Merwin SJ, Obis T, Nunez Y, Re DB. Reply to the Commentary by Lotti M. and Moretto A. "Organophosphate neurotoxicity to the voluntary motor system on the trail of environment-caused amyotrophic lateral sclerosis: the known, the misknown and the unknown. Arch Toxicol 2017; 91:3191-3193. [PMID: 28702692 DOI: 10.1007/s00204-017-2025-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 06/28/2017] [Indexed: 10/19/2022]
Affiliation(s)
- Samantha J Merwin
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, 722 W 168th Street Suite 1107B, New York, NY, 10032, USA.,NIEHS Center for Environmental Health Sciences in Northern Manhattan, Columbia University, New York, NY, 10032, USA.,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA
| | - Teresa Obis
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, 722 W 168th Street Suite 1107B, New York, NY, 10032, USA.,NIEHS Center for Environmental Health Sciences in Northern Manhattan, Columbia University, New York, NY, 10032, USA.,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA
| | - Yanelli Nunez
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, 722 W 168th Street Suite 1107B, New York, NY, 10032, USA.,NIEHS Center for Environmental Health Sciences in Northern Manhattan, Columbia University, New York, NY, 10032, USA.,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA.,Toxicology Ph.D. Program, Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, 10032, USA
| | - Diane B Re
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, 722 W 168th Street Suite 1107B, New York, NY, 10032, USA. .,NIEHS Center for Environmental Health Sciences in Northern Manhattan, Columbia University, New York, NY, 10032, USA. .,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA.
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17
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High concentration of trichlorfon (1 mM) disrupts axonal cytoskeleton and decreases the expression of plasticity-related proteins in SH-SY5Y cells. Toxicol In Vitro 2017; 39:84-92. [DOI: 10.1016/j.tiv.2016.12.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 11/08/2016] [Accepted: 12/02/2016] [Indexed: 11/18/2022]
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18
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McFerrin J, Patton BL, Sunderhaus ER, Kretzschmar D. NTE/PNPLA6 is expressed in mature Schwann cells and is required for glial ensheathment of Remak fibers. Glia 2017; 65:804-816. [PMID: 28206686 PMCID: PMC5357176 DOI: 10.1002/glia.23127] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 01/26/2017] [Accepted: 01/26/2017] [Indexed: 11/08/2022]
Abstract
Neuropathy target esterase (NTE) or patatin-like phospholipase domain containing 6 (PNPLA6) was first linked with a neuropathy occurring after organophosphate poisoning and was later also found to cause complex syndromes when mutated, which can include mental retardation, spastic paraplegia, ataxia, and blindness. NTE/PNPLA6 is widely expressed in neurons but experiments with its Drosophila orthologue Swiss-cheese (SWS) suggested that it may also have glial functions. Investigating whether NTE/PNPLA6 is expressed in glia, we found that NTE/PNPLA6 is expressed by Schwann cells in the sciatic nerve of adult mice with the most prominent expression in nonmyelinating Schwann cells. Within Schwann cells, NTE/PNPLA6 is enriched at the Schmidt-Lanterman incisures and around the nucleus. When analyzing postnatal expression patterns, we did not detect NTE/PNPLA6 in promyelinating Schwann cells, while weak expression was detectable at postnatal day 5 in Schwann cells and increased with their maturation. Interestingly, NTE/PNPLA6 levels were upregulated after nerve crush and localized to ovoids forming along the nerve fibers. Using a GFAP-based knock-out of NTE/PNPLA6, we detected an incomplete ensheathment of Remak fibers whereas myelination did not appear to be affected. These results suggest that NTE/PNPLA6 is involved in the maturation of nonmyelinating Schwann cells during development and de-/remyelination after neuronal injury. Since Schwann cells play an important role in maintaining axonal viability and function, it is therefore likely that changes in Schwann cells contribute to the locomotory deficits and neuropathy observed in patients carrying mutations in NTE.
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Affiliation(s)
- Janis McFerrin
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239
| | - Bruce L Patton
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239
| | - Elizabeth R Sunderhaus
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239.,Molecular and Medical Genetics, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239
| | - Doris Kretzschmar
- Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239.,Molecular and Medical Genetics, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon, 97239
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19
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He X, Gao J, Dong T, Chen M, Zhou K, Chang C, Luo J, Wang C, Wang S, Chen D, Zhou Z, Tian Y, Xia Y, Wang X. Developmental Neurotoxicity of Methamidophos in the Embryo-Larval Stages of Zebrafish. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 14:ijerph14010023. [PMID: 28036051 PMCID: PMC5295274 DOI: 10.3390/ijerph14010023] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 12/20/2016] [Accepted: 12/26/2016] [Indexed: 12/02/2022]
Abstract
Methamidophos is a representative organophosphate insecticide. The knowledge of its developmental neurotoxicity is limited, especially for zebrafish in the early stages of their life. Four hour post-fertilization (hpf) zebrafish embryos were exposed to several environmentally relevant concentrations of methamidophos (0, 25, and 500 μg/L) for up to 72 hpf. Locomotor behavior was then studied in the zebrafish larvae at this timepoint. Acridine orange (AO) staining was carried out in the zebrafish larvae, and the mRNA levels of genes associated with neural development (mbp and syn2a) were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). The number of escape responders for mechanical stimulation was significantly decreased in exposed groups. AO staining showed noticeable signs of apoptosis mainly in the brain. In addition, the mRNA levels of mbp and syn2a were both significantly down-regulated in exposed groups. Our study provides the first evidence that methamidophos exposure can cause developmental neurotoxicity in the early stages of zebrafish life, which may be caused by the effect of methamidophos on neurodevelopmental genes and the activation of cell apoptosis in the brain.
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Affiliation(s)
- Xiaowei He
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
| | - Jiawei Gao
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
| | - Tianyu Dong
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
| | - Minjian Chen
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Wuxi Maternal and Child Health Hospital, Nanjing Medical University, Wuxi 214002, China.
| | - Kun Zhou
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
| | - Chunxin Chang
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
| | - Jia Luo
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
| | - Chao Wang
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
| | - Shoulin Wang
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
| | - Daozhen Chen
- Wuxi Maternal and Child Health Hospital, Nanjing Medical University, Wuxi 214002, China.
| | - Zuomin Zhou
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China.
| | - Ying Tian
- MOE and Shanghai Key Laboratory of Children's Environmental Health, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China.
- Department of Environmental Health, School of Public Health, Shanghai Jiao Tong University, Shanghai 200025, China.
| | - Yankai Xia
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
| | - Xinru Wang
- State Key Laboratory of Reproductive Medicine, Institute of Toxicology, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 211166, China.
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20
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Flunker LK, Nutter TJ, Johnson RD, Cooper BY. DEET potentiates the development and persistence of anticholinesterase dependent chronic pain signs in a rat model of Gulf War Illness pain. Toxicol Appl Pharmacol 2016; 316:48-62. [PMID: 28025109 DOI: 10.1016/j.taap.2016.12.014] [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] [Received: 10/13/2016] [Revised: 12/16/2016] [Accepted: 12/20/2016] [Indexed: 12/18/2022]
Abstract
Exposure to DEET (N,N-diethyl-meta-toluamide) may have influenced the pattern of symptoms observed in soldiers with GWI (Gulf War Illness; Haley and Kurt, 1997). We examined how the addition of DEET (400mg/kg; 50% topical) to an exposure protocol of permethrin (2.6mg/kg; topical), chlorpyrifos (CP; 120mg/kg), and pyridostigmine bromide (PB;13mg/kg) altered the emergence and pattern of pain signs in an animal model of GWI pain (Nutter et al., 2015). Rats underwent behavioral testing before, during and after a 4week exposure: 1) hindlimb pressure withdrawal threshold; 2) ambulation (movement distance and rate); and 3) resting duration. Additional studies were conducted to assess the influence of acute DEET (10-100μM) on muscle and vascular nociceptor Kv7, KDR, Nav1.8 and Nav1.9. We report that a 50% concentration of DEET enhanced the development and persistence of pain-signs. Rats exposed to all 4 compounds exhibited ambulation deficits that appeared 5-12weeks post-exposure and persisted through weeks 21-24. Rats exposed to only three agents (CP or PB excluded), did not fully develop ambulation deficits. When PB was excluded, rats also developed rest duration pain signs, in addition to ambulation deficits. There was no evidence that physiological doses of DEET acutely modified nociceptor Kv7, KDR, Nav1.8 or Nav1.9 activities. Nevertheless, DEET augmented protocols decreased the conductance of Kv7 expressed in vascular nociceptors harvested from chronically exposed rats. We concluded that DEET enhanced the development and persistence of pain behaviors, but the anticholinesterases CP and PB played a determinant role.
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Affiliation(s)
- L K Flunker
- Division of Neuroscience, Dept. of Oral and Maxillofacial Surgery, Box 100416, JHMHC, University of Florida College of Dentistry, Gainesville, FL 32610, USA.
| | - T J Nutter
- Division of Neuroscience, Dept. of Oral and Maxillofacial Surgery, Box 100416, JHMHC, University of Florida College of Dentistry, Gainesville, FL 32610, USA.
| | - R D Johnson
- Dept. of Physiological Sciences, University of Florida College of Veterinary Science, Gainesville, FL 32610, USA.
| | - B Y Cooper
- Division of Neuroscience, Dept. of Oral and Maxillofacial Surgery, Box 100416, JHMHC, University of Florida College of Dentistry, Gainesville, FL 32610, USA.
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21
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Zhu L, Wang P, Sun YJ, Xu MY, Wu YJ. Disturbed phospholipid homeostasis in endoplasmic reticulum initiates tri-o-cresyl phosphate-induced delayed neurotoxicity. Sci Rep 2016; 6:37574. [PMID: 27883027 PMCID: PMC5121615 DOI: 10.1038/srep37574] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 11/01/2016] [Indexed: 11/30/2022] Open
Abstract
Tri-o-cresyl phosphate (TOCP) is a widely used organophosphorus compound, which can cause a neurodegenerative disorder, i.e., organophosphate-induced delayed neurotoxicity (OPIDN). The biochemical events in the initiation of OPIDN were not fully understood except for the essential inhibition of neuropathy target esterase (NTE). NTE, located in endoplasmic reticulum (ER), catalyzes the deacylation of phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) to glycerophosphocholine (GPC). The present study aims to study the changes of ER phospholipids profile as well as levels of important intermediates of phospholipid synthesis such as diacylglycerol (DAG) and phosphatidic acid (PA) at the initiation stage of OPIDN. Hens are the most commonly used animal models of OPIDN. The spinal cord phospholipidomic profiles of hens treated by TOCP were studied by using HPLC-MS-MS. The results revealed that TOCP induced an increase of PC, LPC, and sphingomyelin (SM) levels and a decrease of GPC, phosphatidylethanolamine (PE), lysophosphatidylethanolamine (LPE), lysophosphatidylserine (LPS), phosphatidylglycerol (PG), and phosphatidylinositol (PI) levels., Levels of DAG and PA were also decreased. Pretreatment with phenylmethylsulfonyl fluoride (PMSF) 24 h before TOCP administration prevented OPIDN and restored the TOCP-induced changes of phospholipids except GPC. Thus, the disruption of ER phospholipid homeostasis may contribute to the initiation of organophosphate-induced delayed neurotoxicity.
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Affiliation(s)
- Li Zhu
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100049, China.,Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Pan Wang
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.,Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Ying-Jian Sun
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.,Department of Veterinary Medicine and Animal Science, Beijing Agriculture College, Beijing 102206, China.,Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Ming-Yuan Xu
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.,Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yi-Jun Wu
- Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.,Laboratory of Molecular Toxicology, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
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22
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Abou-Donia MB, Siracuse B, Gupta N, Sobel Sokol A. Sarin (GB, O-isopropyl methylphosphonofluoridate) neurotoxicity: critical review. Crit Rev Toxicol 2016; 46:845-875. [PMID: 27705071 PMCID: PMC5764759 DOI: 10.1080/10408444.2016.1220916] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Sarin (GB, O-isopropyl methylphosphonofluoridate) is a potent organophosphorus (OP) nerve agent that inhibits acetylcholinesterase (AChE) irreversibly. The subsequent build-up of acetylcholine (ACh) in the central nervous system (CNS) provokes seizures and, at sufficient doses, centrally-mediated respiratory arrest. Accumulation of ACh at peripheral autonomic synapses leads to peripheral signs of intoxication and overstimulation of the muscarinic and nicotinic receptors, which is described as "cholinergic crisis" (i.e. diarrhea, sweating, salivation, miosis, bronchoconstriction). Exposure to high doses of sarin can result in tremors, seizures, and hypothermia. More seriously, build-up of ACh at neuromuscular junctions also can cause paralysis and ultimately peripherally-mediated respiratory arrest which can lead to death via respiratory failure. In addition to its primary action on the cholinergic system, sarin possesses other indirect effects. These involve the activation of several neurotransmitters including gamma-amino-butyric acid (GABA) and the alteration of other signaling systems such as ion channels, cell adhesion molecules, and inflammatory regulators. Sarin exposure is associated with symptoms of organophosphate-induced delayed neurotoxicity (OPIDN) and organophosphate-induced chronic neurotoxicity (OPICN). Moreover, sarin has been involved in toxic and immunotoxic effects as well as organophosphate-induced endocrine disruption (OPIED). The standard treatment for sarin-like nerve agent exposure is post-exposure injection of atropine, a muscarinic receptor antagonist, accompanied by an oxime, an AChE reactivator, and diazepam.
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Affiliation(s)
- Mohamed B Abou-Donia
- a Department of Pharmacology and Cancer Biology , Duke University , Durham , NC , USA
| | - Briana Siracuse
- a Department of Pharmacology and Cancer Biology , Duke University , Durham , NC , USA
| | - Natasha Gupta
- a Department of Pharmacology and Cancer Biology , Duke University , Durham , NC , USA
| | - Ashly Sobel Sokol
- a Department of Pharmacology and Cancer Biology , Duke University , Durham , NC , USA
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23
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Emerick GL, Fernandes LS, de Paula ES, Barbosa F, dos Santos NAG, dos Santos AC. In vitro study of the neuropathic potential of the organophosphorus compounds fenamiphos and profenofos: Comparison with mipafox and paraoxon. Toxicol In Vitro 2015; 29:1079-87. [PMID: 25910916 DOI: 10.1016/j.tiv.2015.04.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 03/24/2015] [Accepted: 04/11/2015] [Indexed: 10/23/2022]
Abstract
Organophosphorus-induced delayed neuropathy (OPIDN) is a central-peripheral distal axonopathy that develops 8-14 days after poisoning by a neuropathic organophosphorus compound (OP). Several OPs that caused OPIDN were withdrawn from the agricultural market due to induction of serious delayed effects. Therefore, the development of in vitro screenings able to differentiate neuropathic from non-neuropathic OPs is of crucial importance. Thus, the aim of this study was to evaluate the differences in the neurotoxic effects of mipafox (neuropathic OP) and paraoxon (non-neuropathic OP) in SH-SY5Y human neuroblastoma cells, using the inhibition and aging of neuropathy target esterase (NTE), inhibition of acetylcholinesterase (AChE), activation of calpain, neurite outgrowth, cytotoxicity and intracellular calcium as indicators. Additionally, the potential of fenamiphos and profenofos to cause acute and/or delayed effects was also evaluated. Mipafox had the lowest IC50 and induced the highest percentage of aging of NTE among the OPs evaluated. Only mipafox was able to cause calpain activation after 24 h of incubation. Concentrations of mipafox and fenamiphos which inhibited at least 70% of NTE were also able to reduce neurite outgrowth. Cytotoxicity was higher in non-neuropathic than in neuropathic OPs while the intracellular calcium levels were higher in neuropathic than in non-neuropathic OPs. In conclusion, the SH-SY5Y cellular model was selective to differentiate neuropathic from non-neuropathic OPs; fenamiphos, but not profenofos presented results compatible with the induction of OPIDN.
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Affiliation(s)
- Guilherme L Emerick
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto - FCFRP, USP, Avenida do Café s/n, Monte Alegre, 14040-903 Ribeirão Preto, SP, Brazil; Departamento de Farmácia, Instituto de Ciências da Saúde, Universidade Federal de Mato Grosso - ICS/UFMT/CUS, Sinop, MT, Brazil.
| | - Laís S Fernandes
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto - FCFRP, USP, Avenida do Café s/n, Monte Alegre, 14040-903 Ribeirão Preto, SP, Brazil
| | - Eloísa Silva de Paula
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto - FCFRP, USP, Avenida do Café s/n, Monte Alegre, 14040-903 Ribeirão Preto, SP, Brazil
| | - Fernando Barbosa
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto - FCFRP, USP, Avenida do Café s/n, Monte Alegre, 14040-903 Ribeirão Preto, SP, Brazil
| | - Neife Aparecida Guinaim dos Santos
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto - FCFRP, USP, Avenida do Café s/n, Monte Alegre, 14040-903 Ribeirão Preto, SP, Brazil
| | - Antonio Cardozo dos Santos
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto - FCFRP, USP, Avenida do Café s/n, Monte Alegre, 14040-903 Ribeirão Preto, SP, Brazil
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Fernandes LS, Emerick GL, Santos NAGD, de Paula ES, Barbosa F, Santos ACD. In vitro study of the neuropathic potential of the organophosphorus compounds trichlorfon and acephate. Toxicol In Vitro 2015; 29:522-8. [DOI: 10.1016/j.tiv.2015.01.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 11/13/2014] [Accepted: 01/02/2015] [Indexed: 11/30/2022]
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Abstract
Toxic neuropathy, although rare, is an important consideration in the setting of a known or suspected toxic exposure in the workplace or other environment. This chapter discusses the clinical and electrodiagnostic evaluation of peripheral neuropathies, highlighting findings that direct further workup and may point to specific toxins as etiology. The difficulty of establishing causality of a toxin in relation to peripheral neuropathy is discussed; guidelines for establishing causality are presented. Examples of common industrial toxins are listed, including their typical industrial uses and their mechanisms of action in producing neuropathy. Characteristic clinical presentations of specific toxic neuropathies are highlighted with selected case studies.
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Affiliation(s)
- Ann A Little
- Department of Neurology, University of Michigan Health System, Ann Arbor, MI, USA
| | - James W Albers
- Department of Neurology, University of Michigan Health System, Ann Arbor, MI, USA.
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Pope HM, Voigt MM. Peripheral glia have a pivotal role in the initial response to axon degeneration of peripheral sensory neurons in zebrafish. PLoS One 2014; 9:e103283. [PMID: 25058656 PMCID: PMC4109997 DOI: 10.1371/journal.pone.0103283] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 06/30/2014] [Indexed: 02/07/2023] Open
Abstract
Axon degeneration is a feature of many peripheral neuropathies. Understanding the organismal response to this degeneration may aid in identifying new therapeutic targets for treatment. Using a transgenic zebrafish line expressing a bacterial nitroreductase (Ntr)/mCherry fusion protein in the peripheral sensory neurons of the V, VII, IX, and X cranial nerves, we were able to induce and visualize the pathology of axon degeneration in vivo. Exposure of 4 days post fertilization Ntr larvae to the prodrug metronidazole (Met), which Ntr metabolizes into cytotoxic metabolites, resulted in dose-dependent cell death and axon degeneration. This was limited to the Ntr-expressing sensory neurons, as neighboring glia and motor axons were unaffected. Cell death was rapid, becoming apparent 3-4 hours after Met treatment, and was followed by phagocytosis of soma and axon debris by cells within the nerves and ganglia beginning at 4-5 hours of exposure. Although neutrophils appear to be activated in response to the degenerating neurons, they did not accumulate at the sites of degeneration. In contrast, macrophages were found to be attracted to the sites of the degenerating axons, where they phagocytosed debris. We demonstrated that peripheral glia are critical for both the phagocytosis and inflammatory response to degenerating neurons: mutants that lack all peripheral glia (foxD3-/-; Ntr) exhibit a much reduced reaction to axonal degeneration, resulting in a dramatic decrease in the clearance of debris, and impaired macrophage recruitment. Overall, these results show that this zebrafish model of peripheral sensory axon degeneration exhibits many aspects common to peripheral neuropathies and that peripheral glia play an important role in the initial response to this process.
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Affiliation(s)
- Holly M. Pope
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
| | - Mark M. Voigt
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, St. Louis, Missouri, United States of America
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Jiang Y, Liu X, Li S, Zhang Y, Piao F, Sun X. Identification of differentially expressed proteins related to organophosphorus-induced delayed neuropathy in the brains of hens. J Appl Toxicol 2013; 34:1352-60. [PMID: 24338829 DOI: 10.1002/jat.2965] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2013] [Revised: 10/17/2013] [Accepted: 10/22/2013] [Indexed: 12/17/2022]
Abstract
Some organophosphorus compounds can cause organophosphate-induced delayed neuropathy (OPIDN). Incidents have been documented for decades, however, little is known about which proteins contribute to the initiation, progression and development of OPIDN. In this study, 51 hens were divided into three groups. The tri-ortho-cresyl-phosphate (TOCP) group was treated with 1000 mg kg(-1) TOCP whereas the control group was treated with an equivalent volume of vehicle. The PMSF + TOCP group was treated subcutaneously with 40 mg kg(-1) phenylmethylsulfonyl fluoride (PMSF), followed by 1000 mg kg(-1) TOCP 24 h later. Proteins in the brains of hens were separated by two-dimensional polyacrylamide gel electrophoresis on day 5 after TOCP administration. Mass spectrometry identified eight differentially expressed proteins. Among these proteins, downregulated expression of glutamine synthetase (GS) in the brains of hens after TOCP treatment was further confirmed by real time RT-PCR and ELISA. Moreover, the brains of hens exposed to TOCP exhibited increased levels of glutamate (Glu) and cytosolic calcium concentration ([Ca(2+)](i)), and a decreased level of glutamine (Gln). However, there were no significant differences in GS expression or levels of Glu, Gln, and [Ca(2+)](i) in the brains of hens among the groups on day 21 after TOCP administration. These results indicate that TOCP exposure downregulates GS expression in the brains of hens, and that downregulation of GS is accompanied by increased levels of Glu and [Ca(2+)](i) in the early stage after TOCP administration. It is also suggested that the downregulated expression of GS might be associated with OPIDN through the disruption of homeostasis of the Glu-Gln cycle and [Ca(2+) ](i).
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Affiliation(s)
- Ying Jiang
- Department of Occupational and Environmental of Health, Dalian Medical University, No. 9 Western Section of Lushun South Road, Dalian, Liaoning, 116044, China
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Krause KH, van Thriel C, De Sousa PA, Leist M, Hengstler JG. Monocrotophos in Gandaman village: India school lunch deaths and need for improved toxicity testing. Arch Toxicol 2013; 87:1877-81. [PMID: 23943209 DOI: 10.1007/s00204-013-1113-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 08/01/2013] [Indexed: 12/22/2022]
Affiliation(s)
- Karl-Heinz Krause
- Department of Pathology and Immunology, Geneva Medical Faculty, Centre Medical Universitaire, University of Geneva (UNIGE), 1, rue Michel-Servet, 1211, Geneva 4, Switzerland,
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Emerick GL, Ehrich M, Jortner BS, Oliveira RV, Deoliveira GH. Biochemical, histopathological and clinical evaluation of delayed effects caused by methamidophos isoforms and TOCP in hens: ameliorative effects using control of calcium homeostasis. Toxicology 2012; 302:88-95. [PMID: 22974967 DOI: 10.1016/j.tox.2012.08.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Revised: 07/23/2012] [Accepted: 08/01/2012] [Indexed: 10/28/2022]
Abstract
This work evaluated the potential of the isoforms of methamidophos to cause organophosphorus-induced delayed neuropathy (OPIDN) in hens. In addition to inhibition of neuropathy target esterase (NTE) and acetylcholinesterase (AChE), calpain activation, spinal cord lesions and clinical signs were assessed. The isoforms (+)-, (±)- and (-)-methamidophos were administered at 50mg/kg orally; tri-ortho-cresyl phosphate (TOCP) was administered (500mg/kg, po) as positive control for delayed neuropathy. The TOCP hens showed greater than 80% and approximately 20% inhibition of NTE and AChE in hen brain, respectively. Among the isoforms of methamidophos, only the (+)-methamidophos was capable of inhibiting NTE activity (approximately 60%) with statistically significant difference compared to the control group. Calpain activity in brain increased by 40% in TOCP hens compared to the control group when measured 24h after dosing and remained high (18% over control) 21 days after dosing. Hens that received (+)-methamidophos had calpain activity 12% greater than controls. The histopathological findings and clinical signs corroborated the biochemical results that indicated the potential of the (+)-methamidophos to be the isoform responsible for OPIDN induction. Protection against OPIDN was examined using a treatment of 2 doses of nimodipine (1mg/kg, i.m.) and one dose of calcium gluconate (5mg/kg, i.v.). The treatment decreased the effect of OPIDN-inducing TOCP and (+)-methamidophos on calpain activity, spinal cord lesions and clinical signs.
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Affiliation(s)
- Guilherme L Emerick
- Department of Natural Active Principles and Toxicology, School of Pharmaceutical Science, Univ Estadual Paulista - UNESP, Araraquara, SP, Brazil.
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