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Zhang Y, Jiang Y, Yu Z, Li Y, Lin X, Weng Y, Guo Z, Hu H, Shao W, Yu G, Zheng F, Cai P, Li H, Wu S. VGluT2 neuron subtypes in the paraventricular thalamic nucleus regulate depression in paraquat-induced Parkinson's disease. JOURNAL OF HAZARDOUS MATERIALS 2024; 472:134559. [PMID: 38735189 DOI: 10.1016/j.jhazmat.2024.134559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 04/14/2024] [Accepted: 05/05/2024] [Indexed: 05/14/2024]
Abstract
Parkinson's disease (PD) is a prevalent neurodegenerative disease and approximately one third of patients with PD are estimated to experience depression. Paraquat (PQ) is the most widely used herbicide worldwide and PQ exposure is reported to induce PD with depression. However, the specific brain region and neural networks underlying the etiology of depression in PD, especially in the PQ-induced model, have not yet been elucidated. Here, we report that the VGluT2-positive glutamatergic neurons in the paraventricular thalamic nucleus (PVT) promote depression in the PQ-induced PD mouse model. Our results show that PVTVGluT2 neurons are activated by PQ and their activation increases the susceptibility to depression in PD mice. Conversely, inhibition of PVTVGluT2 neurons reversed the depressive-behavioral changes induced by PQ. Similar to the effects of intervention the soma of PVTVGluT2 neurons, stimulation of their projections into the central amygdaloid nucleus (CeA) also strongly influenced depression in PD mice. PQ induced malfunctioning of the glutamate system and changes in the dendritic and synaptic morphology in the CeA through its role on PVTVGluT2 neuronal activation. In summary, our results demonstrate that PVTVGluT2 neurons are key neuronal subtypes for depression in PQ-induced PD and promote depression processes through the PVTVGluT2-CeA pathway.
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Affiliation(s)
- Yu Zhang
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Yihua Jiang
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Zhen Yu
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Yinhan Li
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Xinpei Lin
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Yali Weng
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Zhenkun Guo
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Hong Hu
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Wenya Shao
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Guangxia Yu
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Fuli Zheng
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Ping Cai
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Huangyuan Li
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China; The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China.
| | - Siying Wu
- The Key Laboratory of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Provincial Key Laboratory of Environmental Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Department of Epidemiology and Health Statistics, School of Public Health, Fujian Medical University, Fuzhou 350122, China.
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Shi G, Zhang C, Bai X, Sun J, Wang K, Meng Q, Li Y, Hu G, Hu R, Cai Q, Huang M. A potential mechanism clue to the periodic storm from microglia activation and progressive neuron damage induced by paraquat exposure. ENVIRONMENTAL TOXICOLOGY 2024; 39:1874-1888. [PMID: 38189626 DOI: 10.1002/tox.24053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 07/24/2023] [Accepted: 11/10/2023] [Indexed: 01/09/2024]
Abstract
Paraquat (PQ), is characterized by neurotoxicity, which increases the potential risk of Parkinson's disease (PD) exposure in the long-term and low doses. Triggering microglia activation and neuroinflammation is deemed an early event resulting in PD. However, the underlying pathogenesis of PD by PQ is not clear yet. In this article, C57BL/6J mice treated with PQ could successfully act out Parkinson-like. In addition, we observed the fluorescence intensity enhancement of Iba-1 activated microglia with released pro-inflammatory, all ahead of both the damage of dopaminergic neurons in the substantia nigra and corpus striatum of the brain. Surprisingly, the injection of minocycline before PQ for many hours not only can effectively improve the neurobehavioral symptoms of mice but inhibit the activation of microglia and the release of pro-inflammatory substances, even controlling the gradual damage and loss of neurons. A further mechanism of minocycline hampered the expression levels of key signaling proteins PI3K, PDK1, p-AKT, and CD11b (the receptor of microglia membrane recognition), while a large number of inflammatory factors. Our results suggested that the CD11b/PI3K/NOX2 pathway may be a clue that microglia-mediated inflammatory responses and neuronal damage in a PQ-induced abnormal behavior Parkinson-like mouse.
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Affiliation(s)
- Ge Shi
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Chunhui Zhang
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Xinghua Bai
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Jian Sun
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
| | - KaiDong Wang
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Qi Meng
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Yang Li
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Guiling Hu
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Rong Hu
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Qian Cai
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Min Huang
- School of Public Health, Ningxia Medical University, Yinchuan, Ningxia, China
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health of Ningxia Medical University, Yinchuan, Ningxia, China
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Zuo Z, Li J, Zhang B, Hang A, Wang Q, Xiong G, Tang L, Zhou Z, Chang X. Early-Life Exposure to Paraquat Aggravates Sex-Specific and Progressive Abnormal Non-Motor Neurobehavior in Aged Mice. TOXICS 2023; 11:842. [PMID: 37888693 PMCID: PMC10611227 DOI: 10.3390/toxics11100842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 10/28/2023]
Abstract
Early-life exposure to environmental neurotoxicants is known to have lasting effects on organisms. In this study, we aim to investigate the impacts of PQ exposure during early developmental stages and adult re-challenge in aged mice on non-motor neurobehavior. Two mouse models, which were exposed once during early life stage and re-exposure at adulthood, were created to explore the long-term effects of PQ on non-motor neurobehavior. As the results showed, early-life exposure to PQ caused impairment in working memory and cognitive ability in aged male mice, but not in female mice, exhibiting a sex-specific impairment. Moreover, male mice that were re-challenged with PQ at adulthood following early-life exposure also exhibited non-motor neurobehavioral disorders. Notably, re-exposure to PQ exacerbated neurobehavioral disorders and anxiety levels compared to single exposure during different life stages. Collectively, early-life exposure to PQ can result in irreversible impairments in non-motor neurobehavior and increase susceptibility to subsequent insults in male mice, but not in female mice, suggesting greater sensitivity in male rodents to PQ-induced non-motor neurobehavioral deficits.
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Affiliation(s)
- Zhenzi Zuo
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Shanghai Medical College of Fudan University, Fudan University, Room 233, Building 8, 130 Dongan Road, Shanghai 200032, China; (Z.Z.); (J.L.); (B.Z.); (A.H.); (G.X.); (Z.Z.)
| | - Jiayi Li
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Shanghai Medical College of Fudan University, Fudan University, Room 233, Building 8, 130 Dongan Road, Shanghai 200032, China; (Z.Z.); (J.L.); (B.Z.); (A.H.); (G.X.); (Z.Z.)
| | - Bing Zhang
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Shanghai Medical College of Fudan University, Fudan University, Room 233, Building 8, 130 Dongan Road, Shanghai 200032, China; (Z.Z.); (J.L.); (B.Z.); (A.H.); (G.X.); (Z.Z.)
| | - Ai Hang
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Shanghai Medical College of Fudan University, Fudan University, Room 233, Building 8, 130 Dongan Road, Shanghai 200032, China; (Z.Z.); (J.L.); (B.Z.); (A.H.); (G.X.); (Z.Z.)
| | - Qiaoxu Wang
- Pharmacology and Toxicology Department, Shanghai Institute for Food and Drug Control, Shanghai 201203, China; (Q.W.); (L.T.)
| | - Guiya Xiong
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Shanghai Medical College of Fudan University, Fudan University, Room 233, Building 8, 130 Dongan Road, Shanghai 200032, China; (Z.Z.); (J.L.); (B.Z.); (A.H.); (G.X.); (Z.Z.)
| | - Liming Tang
- Pharmacology and Toxicology Department, Shanghai Institute for Food and Drug Control, Shanghai 201203, China; (Q.W.); (L.T.)
| | - Zhijun Zhou
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Shanghai Medical College of Fudan University, Fudan University, Room 233, Building 8, 130 Dongan Road, Shanghai 200032, China; (Z.Z.); (J.L.); (B.Z.); (A.H.); (G.X.); (Z.Z.)
| | - Xiuli Chang
- School of Public Health and Key Laboratory of Public Health Safety of the Ministry of Education, Shanghai Medical College of Fudan University, Fudan University, Room 233, Building 8, 130 Dongan Road, Shanghai 200032, China; (Z.Z.); (J.L.); (B.Z.); (A.H.); (G.X.); (Z.Z.)
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Atone J, Wagner K, Koike S, Yang J, Hwang SH, Hammock BD. Inhibition of soluble epoxide hydrolase reduces paraquat neurotoxicity in rodents. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2023; 98:104070. [PMID: 36682504 PMCID: PMC9992278 DOI: 10.1016/j.etap.2023.104070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 01/15/2023] [Accepted: 01/18/2023] [Indexed: 06/17/2023]
Abstract
Given the paucity of research surrounding the effect of chronic paraquat on striatal neurotoxicity, there is a need for further investigation into the neurotoxic effects of paraquat in mouse striatum. Furthermore, while previous studies have shown that inhibiting soluble epoxide hydrolase mitigates MPTP-mediated endoplasmic reticulum stress in mouse striatum, its effect on paraquat toxicity is still unknown. Thus, this study attempts to observe changes in inflammatory and endoplasmic reticulum stress markers in mouse striatum following chronic paraquat administration to determine whether inhibiting soluble epoxide hydrolase mitigates paraquat-induced neurotoxicity and whether it can reduce TLR4-mediated inflammation in primary astrocytes and microglia. Our results show that while the pro-inflammatory effect of chronic paraquat is small, there is a significant induction of inflammatory and cellular stress markers, such as COX2 and CHOP, that can be mitigated through a prophylactic administration of a soluble epoxide hydrolase inhibitor.
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Affiliation(s)
- Jogen Atone
- Department of Entomology and Nematology, and UC Davis Comprehensive Cancer Center, University of California Davis, Davis, CA 95616, USA
| | - Karen Wagner
- Department of Entomology and Nematology, and UC Davis Comprehensive Cancer Center, University of California Davis, Davis, CA 95616, USA
| | - Shinichiro Koike
- Department of Nutrition, University of California Davis, Davis, CA 95616, USA
| | - Jun Yang
- Department of Entomology and Nematology, and UC Davis Comprehensive Cancer Center, University of California Davis, Davis, CA 95616, USA
| | - Sung Hee Hwang
- Department of Entomology and Nematology, and UC Davis Comprehensive Cancer Center, University of California Davis, Davis, CA 95616, USA
| | - Bruce D Hammock
- Department of Entomology and Nematology, and UC Davis Comprehensive Cancer Center, University of California Davis, Davis, CA 95616, USA.
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Thirugnanam T, Santhakumar K. Chemically induced models of Parkinson's disease. Comp Biochem Physiol C Toxicol Pharmacol 2022; 252:109213. [PMID: 34673252 DOI: 10.1016/j.cbpc.2021.109213] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/30/2021] [Accepted: 10/14/2021] [Indexed: 12/12/2022]
Abstract
Environmental toxins are harmful substances detrimental to humans. Constant exposure to these fatal neurotoxins can cause various neurodegenerative disorders. Although poisonous, specific neurotoxins at optimal concentrations mimic the clinical features of neurodegenerative diseases in several animal models. Such chemically-induced model systems are beneficial in deciphering the molecular mechanisms of neurodegeneration and drug screening for these disorders. One such neurotoxin is 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), a widely used chemical that recapitulates Parkinsonian features in various animal models. Apart from MPTP, other neurotoxins like 6-hydroxydopamine (6-OHDA), paraquat, rotenone also induce specific clinical features of Parkinson's disease in animal models. These chemically-induced Parkinson's disease models are playing a crucial role in understanding Parkinson's disease onset, pathology, and novel therapeutics. In this review, we provide a concise overview of various neurotoxins that can recapitulate Parkinsonian features in different in vivo and in vitro model systems specifically focusing on the different treatment methodologies of neurotoxins.
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Affiliation(s)
- Thilaga Thirugnanam
- Zebrafish Genetics Laboratory, Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India
| | - Kirankumar Santhakumar
- Zebrafish Genetics Laboratory, Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India.
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Bacopaside-I Alleviates the Detrimental Effects of Acute Paraquat Intoxication in the Adult Zebrafish Brain. Neurochem Res 2021; 46:3059-3074. [PMID: 34357519 DOI: 10.1007/s11064-021-03416-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 07/26/2021] [Accepted: 08/02/2021] [Indexed: 02/07/2023]
Abstract
Paraquat (PQ), an environmental neurotoxicant, causes acute fatal poisoning upon accidental or intentional ingestion (suicidal cases) worldwide. To date, an effective remedy for PQ toxicity is not available. In this study, we have evaluated the therapeutic efficacy of Bacopaside-I (BS-I), an active compound found in the plant extract of Bacopa monnieri (Brahmi), against acute PQ intoxication using zebrafish as a model organism. Adult zebrafish were injected with a dose of either 30 mg/kg or 50 mg/kg PQ. PQ-intoxicated zebrafish showed an increased rate of mortality and oxidative imbalance in their brain. Also, the proliferation of neural cells in the adult zebrafish brain was inhibited. However, when BS-I pretreated zebrafish were intoxicated with PQ, the toxic effects of PQ were ameliorated. PQ treatment also affected the expression of particular genes concerned with the apoptosis and dopamine signaling, which was not altered by BS-I administration. Our results highlight the efficiency of BS-I as a novel therapeutic agent for PQ intoxication. It further compels us to search and evaluate the molecular mechanisms targeted by BS-I to develop a potent therapy for acute PQ intoxication.
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Stevens AJ, Campbell JL, Travis KZ, Clewell HJ, Hinderliter PM, Botham PA, Cook AR, Minnema DJ, Wolf DC. Paraquat pharmacokinetics in primates and extrapolation to humans. Toxicol Appl Pharmacol 2021; 417:115463. [PMID: 33631232 DOI: 10.1016/j.taap.2021.115463] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 02/12/2021] [Accepted: 02/14/2021] [Indexed: 11/28/2022]
Abstract
By extending our Paraquat (PQ) work to include primates we have implemented a modelling and simulation strategy that has enabled PQ pharmacokinetic data to be integrated into a single physiologically based pharmacokinetic (PBPK) model that enables more confident extrapolation to humans. Because available data suggested there might be differences in PQ kinetics between primates and non-primates, a radiolabelled study was conducted to characterize pharmacokinetics and excretion in Cynomolgus monkeys. Following single intravenous doses of 0.01 or 0.1 mg paraquat dichloride/kg bw, plasma PQ concentration-time profiles were dose-proportional. Excretion up to 48 h (predominantly urinary) was 82.9%, with ca. 10% remaining unexcreted. In vitro blood binding was similar across Cynomolgus monkeys, humans and rat. Our PBPK model for the rat, mouse and dog, employing a single set of PQ-specific parameters, was scaled to Cynomolgus monkeys and well represented the measured plasma concentration-time profiles over 14 days. Addition of a cartilage compartment to the model better captured the percent remaining in the monkeys at 48 h, whilst having negligible effect on model predictions for the other species. The PBPK model performed well for all four species, demonstrating there is little difference in PQ kinetics between non-primates and primates enabling a more confident extrapolation to humans. Scaling of the PBPK model to humans, with addition of a human-specific dermal submodel based on in vitro human dermal absorption data, provides a valuable tool that could be employed in defining internal dosimetry to complement human health risk assessments.
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Affiliation(s)
- Alexander J Stevens
- Syngenta Ltd, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK.
| | - Jerry L Campbell
- Ramboll Environment and Health Consulting, 3214 Charles B. Root Wynd Suite 130, Raleigh, NC 27612, USA.
| | - Kim Z Travis
- Syngenta Ltd, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK.
| | - Harvey J Clewell
- Ramboll Environment and Health Consulting, 3214 Charles B. Root Wynd Suite 130, Raleigh, NC 27612, USA.
| | | | - Philip A Botham
- Syngenta Ltd, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK.
| | - Andrew R Cook
- Syngenta Ltd, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK.
| | - Daniel J Minnema
- Syngenta Crop Protection LLC, P.O. Box 18300, Greensboro, NC, USA.
| | - Douglas C Wolf
- Syngenta Crop Protection LLC, Research Triangle Park, NC 27709, USA.
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Campbell JL, Travis KZ, Clewell HJ, Stevens AJ, Hinderliter PM, Andersen ME, Botham PA, Cook AR, Minnema DJ, Wolf DC. Integration of paraquat pharmacokinetic data across species using PBPK modelling. Toxicol Appl Pharmacol 2021; 417:115462. [PMID: 33631233 DOI: 10.1016/j.taap.2021.115462] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 02/12/2021] [Accepted: 02/14/2021] [Indexed: 11/15/2022]
Abstract
Paraquat dichloride (PQ) is a non-selective herbicide which has been the subject of numerous toxicology studies over more than 50 years. This paper describes the development of a physiologically-based pharmacokinetic (PBPK) model of PQ kinetics for the rat, mouse and dog, firstly to aid the interpretation of studies in which no kinetic measurements were made, and secondly to enable the future extension of the model to humans. Existing pharmacokinetic data were used to develop a model for the rat and mouse. Simulations with this preliminary model were then used to identify key data gaps and to design a new blood binding study to reduce uncertainty in critical aspects of the model. The new data provided evidence to support the model structure, and its predictive performance was then assessed against dog and rat datasets not used in model development. The PQ-specific model parameters are the same for all three species, with only the physiological parameters varying between species. This consistency across species provides a strong basis for extrapolation to other species, as demonstrated here for the dog. The model enables a wide range of PQ data to be linked together to provide a broad understanding of PQ pharmacokinetics in rodents and the dog, showing that the key aspects of PQ kinetics in these species are understood and adequately encapsulated within the model.
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Affiliation(s)
- Jerry L Campbell
- Ramboll Environment and Health Consulting, 3214 Charles B. Root Wynd Suite 130, Raleigh, NC 27612, USA.
| | - Kim Z Travis
- Syngenta Ltd, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK.
| | - Harvey J Clewell
- Ramboll Environment and Health Consulting, 3214 Charles B. Root Wynd Suite 130, Raleigh, NC 27612, USA.
| | - Alexander J Stevens
- Syngenta Ltd, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK.
| | | | - Melvin E Andersen
- Andersen ToxConsulting LLC, 424 Granite Lake CT, Denver, NC 28037, USA
| | - Philip A Botham
- Syngenta Ltd, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK.
| | - Andrew R Cook
- Syngenta Ltd, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK.
| | - Daniel J Minnema
- Syngenta Crop Protection LLC, P.O. Box 18300, Greensboro, NC, USA.
| | - Douglas C Wolf
- Syngenta Crop Protection LLC, Research Triangle Park, NC 27709, USA.
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Rai SN, Singh P. Advancement in the modelling and therapeutics of Parkinson's disease. J Chem Neuroanat 2020; 104:101752. [PMID: 31996329 DOI: 10.1016/j.jchemneu.2020.101752] [Citation(s) in RCA: 93] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 01/19/2020] [Accepted: 01/20/2020] [Indexed: 02/08/2023]
Abstract
Since the discovery of L-dopa in the middle of the 20th century (1960s), there is not any neuroprotective therapy available although significant development has been made in the treatment of symptomatic Parkinson's disease (PD). Neurological disorders like PD can be modelled in animals so as to recapitulates most of the symptoms seen in PD patients. In aging population, PD is the second most common neurodegenerative disease after Alzheimer's disease, even though significant outcomes have been achieved in PD research yet it still is a mystery to solve the treatments for PD. In the last two decades, PD models have provided enhanced precision into the understanding of the process of PD disease, its etiology, pathology, and molecular mechanisms behind it. Furthermore, at the same time as cellular models have helped to recognize specific events, animal models, both toxic and genetic, have replicated almost all of the hallmarks of PD and are very helpful for testing and finding new strategies for neuroprotection. Recently, in both classical and newer models, major advances have been done in the modelling of supplementary PD features have come into the light. In this review, we have try to provide an updated summary of the characteristics of these models related to in vitro and in vivo models, animal models for PD, stem cell model for PD, newer 3D model as well as the strengths and limitations of these most popular PD models.
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Affiliation(s)
- Sachchida Nand Rai
- Department of Zoology, Mahila Maha Vidhyalaya, Institute of Science, Banaras Hindu University, Varanasi, India.
| | - Payal Singh
- Department of Zoology, Mahila Maha Vidhyalaya, Institute of Science, Banaras Hindu University, Varanasi, India.
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Joseph TP, Jagadeesan N, Sai LY, Lin SL, Sahu S, Schachner M. Adhesion Molecule L1 Agonist Mimetics Protect Against the Pesticide Paraquat-Induced Locomotor Deficits and Biochemical Alterations in Zebrafish. Front Neurosci 2020; 14:458. [PMID: 32547358 DOI: 10.3389/fnins.2020.00458.ecollection2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 04/15/2020] [Indexed: 04/04/2023] Open
Abstract
Besides several endogenous elements, exogenous factors, including exposure to pesticides, have been recognized as putative factors contributing to the onset and development of neurodegenerative diseases, including Parkinson's disease (PD). Considering the availability, success rate, and limitations associated with the current arsenals to fight PD, there is an unmet need for novel therapeutic interventions. Therefore, based on the previously reported beneficial functions of the L1 cell adhesion molecule, we hypothesized that L1 mimetic compounds may serve to neutralize neurotoxicity triggered by the pesticide paraquat (PQ). In this study, we attempt to use PQ for inducing PD-like pathology and the L1 mimetic compounds phenelzine sulfate (PS) and tacrine (TC) as potential candidates for the amelioration of PD symptoms using zebrafish as a model system. Administration of PQ together with the L1 mimetic compounds PS or TC (250 nM) improved survival of zebrafish larvae, protected them from locomotor deficits, and increased their sensorimotor reflexes. Moreover, application of PQ together with PS (500 nM) or TC (1000 nM) in adult zebrafish counteracted PQ-induced toxicity, maintaining normal locomotor functions and spatial memory in an open field and T-maze task, respectively. Both L1 mimetic compounds prevented reduction in tyrosine hydroxylase and dopamine levels, reduced reactive oxygen species (ROS) generation, protected against impairment of mitochondrial viability, improved the antioxidant enzyme system, and prevented a decrease in ATP levels. Altogether, our findings highlight the beneficial functions of the agonistic L1 mimetics PS and TC by improving several vital cell functions against PQ-triggered neurotoxicity.
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Affiliation(s)
| | - Nataraj Jagadeesan
- Center of Neuroscience, Shantou University Medical College, Shantou, China
| | - Liu Yang Sai
- Center of Neuroscience, Shantou University Medical College, Shantou, China
| | - Stanley Li Lin
- Department of Cell Biology, Shantou University Medical College, Shantou, China
- Guangdong Provincial Key Laboratory for Breast Cancer Diagnosis and Treatment, Shantou University Medical College, Shantou, China
| | - Sudhanshu Sahu
- Center of Neuroscience, Shantou University Medical College, Shantou, China
| | - Melitta Schachner
- Center of Neuroscience, Shantou University Medical College, Shantou, China
- Keck Center for Collaborative Neuroscience, Department of Cell Biology and Neuroscience, School of Arts and Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, United States
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Joseph TP, Jagadeesan N, Sai LY, Lin SL, Sahu S, Schachner M. Adhesion Molecule L1 Agonist Mimetics Protect Against the Pesticide Paraquat-Induced Locomotor Deficits and Biochemical Alterations in Zebrafish. Front Neurosci 2020; 14:458. [PMID: 32547358 PMCID: PMC7270331 DOI: 10.3389/fnins.2020.00458] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 04/15/2020] [Indexed: 02/05/2023] Open
Abstract
Besides several endogenous elements, exogenous factors, including exposure to pesticides, have been recognized as putative factors contributing to the onset and development of neurodegenerative diseases, including Parkinson's disease (PD). Considering the availability, success rate, and limitations associated with the current arsenals to fight PD, there is an unmet need for novel therapeutic interventions. Therefore, based on the previously reported beneficial functions of the L1 cell adhesion molecule, we hypothesized that L1 mimetic compounds may serve to neutralize neurotoxicity triggered by the pesticide paraquat (PQ). In this study, we attempt to use PQ for inducing PD-like pathology and the L1 mimetic compounds phenelzine sulfate (PS) and tacrine (TC) as potential candidates for the amelioration of PD symptoms using zebrafish as a model system. Administration of PQ together with the L1 mimetic compounds PS or TC (250 nM) improved survival of zebrafish larvae, protected them from locomotor deficits, and increased their sensorimotor reflexes. Moreover, application of PQ together with PS (500 nM) or TC (1000 nM) in adult zebrafish counteracted PQ-induced toxicity, maintaining normal locomotor functions and spatial memory in an open field and T-maze task, respectively. Both L1 mimetic compounds prevented reduction in tyrosine hydroxylase and dopamine levels, reduced reactive oxygen species (ROS) generation, protected against impairment of mitochondrial viability, improved the antioxidant enzyme system, and prevented a decrease in ATP levels. Altogether, our findings highlight the beneficial functions of the agonistic L1 mimetics PS and TC by improving several vital cell functions against PQ-triggered neurotoxicity.
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Affiliation(s)
| | - Nataraj Jagadeesan
- Center of Neuroscience, Shantou University Medical College, Shantou, China
| | - Liu Yang Sai
- Center of Neuroscience, Shantou University Medical College, Shantou, China
| | - Stanley Li Lin
- Department of Cell Biology, Shantou University Medical College, Shantou, China
- Guangdong Provincial Key Laboratory for Breast Cancer Diagnosis and Treatment, Shantou University Medical College, Shantou, China
| | - Sudhanshu Sahu
- Center of Neuroscience, Shantou University Medical College, Shantou, China
| | - Melitta Schachner
- Center of Neuroscience, Shantou University Medical College, Shantou, China
- Keck Center for Collaborative Neuroscience, Department of Cell Biology and Neuroscience, School of Arts and Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ, United States
- *Correspondence: Melitta Schachner, ;
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13
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Cheng YH, Chou WC, Yang YF, Huang CW, How CM, Chen SC, Chen WY, Hsieh NH, Lin YJ, You SH, Liao CM. Response to "Letter to the editor re: Cheng YH, Chou WC, Yang YF, et al. Environ Sci Pollut Res (2018). https://doi.org/10.107/s11356-017-0875-4". ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:33836-33839. [PMID: 30215207 DOI: 10.1007/s11356-018-3178-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 09/06/2018] [Indexed: 06/08/2023]
Affiliation(s)
- Yi-Hsien Cheng
- Institute of Computational Comparative Medicine, Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Wei-Chun Chou
- Institute of Computational Comparative Medicine, Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Ying-Fei Yang
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, 10617, Taiwan, Republic of China
| | - Chi-Wei Huang
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, 10617, Taiwan, Republic of China
| | - Chun Ming How
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, 10617, Taiwan, Republic of China
| | - Szu-Chieh Chen
- Department of Public Health, Chung Shan Medical University, Taichung, 40201, Taiwan, Republic of China
- Department of Family and Community Medicine, Chung Shan Medical University Hospital, Taichung, 40201, Taiwan, Republic of China
| | - Wei-Yu Chen
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan, Republic of China
- Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan, Republic of China
| | - Nan-Hung Hsieh
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77845, USA
| | - Yi-Jun Lin
- Institute of Food Safety and Health Risk Assessment, National Yang-Ming University, Taipei, 11221, Taiwan, Republic of China
| | - Shu-Han You
- Institute of Food Safety and Risk Management, National Taiwan Ocean University, Keelung, 20224, Taiwan, Republic of China
| | - Chung-Min Liao
- Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, 10617, Taiwan, Republic of China.
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14
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Travis KZ, Clewell HJ, Campbell JL, Hinderliter PM. Letter to the editor re: Cheng, YH., Chou, WC., Yang, YF. et al. Environ Sci Pollut Res (2017). https://doi.org/10.1007/s11356-017-0875-4. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:33832-33835. [PMID: 30291613 PMCID: PMC6245011 DOI: 10.1007/s11356-018-3371-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 09/28/2018] [Indexed: 06/08/2023]
Affiliation(s)
- Kim Z Travis
- Syngenta Ltd, Jealott’s Hill International Research Centre, Bracknell, Berkshire RG42 6EY UK
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15
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Pramipexole and Fingolimod exert neuroprotection in a mouse model of Parkinson's disease by activation of sphingosine kinase 1 and Akt kinase. Neuropharmacology 2018; 135:139-150. [DOI: 10.1016/j.neuropharm.2018.02.023] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 02/14/2018] [Accepted: 02/22/2018] [Indexed: 12/14/2022]
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16
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Vaz RL, Outeiro TF, Ferreira JJ. Zebrafish as an Animal Model for Drug Discovery in Parkinson's Disease and Other Movement Disorders: A Systematic Review. Front Neurol 2018; 9:347. [PMID: 29910763 PMCID: PMC5992294 DOI: 10.3389/fneur.2018.00347] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 04/30/2018] [Indexed: 12/21/2022] Open
Abstract
Movement disorders can be primarily divided into hypokinetic and hyperkinetic. Most of the hypokinetic syndromes are associated with the neurodegenerative disorder Parkinson’s disease (PD). By contrast, hyperkinetic syndromes encompass a broader array of diseases, including dystonia, essential tremor, or Huntington’s disease. The discovery of effective therapies for these disorders has been challenging and has also involved the development and characterization of accurate animal models for the screening of new drugs. Zebrafish constitutes an alternative vertebrate model for the study of movement disorders. The neuronal circuitries involved in movement in zebrafish are well characterized, and most of the associated molecular mechanisms are highly conserved. Particularly, zebrafish models of PD have contributed to a better understanding of the role of several genes implicated in the disease. Furthermore, zebrafish is a vertebrate model particularly suited for large-scale drug screenings. The relatively small size of zebrafish, optical transparency, and lifecycle, are key characteristics that facilitate the study of multiple compounds at the same time. Several transgenic, knockdown, and mutant zebrafish lines have been generated and characterized. Therefore, it is central to critically analyze these zebrafish lines and understand their suitability as models of movement disorders. Here, we revise the pathogenic mechanisms, phenotypes, and responsiveness to pharmacotherapies of zebrafish lines of the most common movement disorders. A systematic review of the literature was conducted by including all studies reporting the characterization of zebrafish models of the movement disorders selected from five bibliographic databases. A total of 63 studies were analyzed, and the most relevant data within the scope of this review were gathered. The majority (62%) of the studies were focused in the characterization of zebrafish models of PD. Overall, the zebrafish models included display conserved biochemical and neurobehavioral features of the phenomenology in humans. Nevertheless, in light of what is known for all animal models available, the use of zebrafish as a model for drug discovery requires further optimization. Future technological developments alongside with a deeper understanding of the molecular bases of these disorders should enable the development of novel zebrafish lines that can prove useful for drug discovery for movement disorders.
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Affiliation(s)
- Rita L Vaz
- TechnoPhage, SA, Lisboa, Portugal.,Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Tiago F Outeiro
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany.,Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany.,CEDOC, Chronic Diseases Research Centre, Faculdade de Ciências Médicas, NOVA Medical School, Universidade NOVA de Lisboa, Lisboa, Portugal.,The Medical School, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Joaquim J Ferreira
- Faculdade de Medicina, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, Portugal.,Laboratory of Clinical Pharmacology and Therapeutics, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,CNS-Campus Neurológico Sénior, Torres Vedras, Portugal
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17
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Li Z, Zheng J, Zhang XF. Detrimental Effects of Paraquat on Astrocytes-Regulating Synaptic Functions. Dose Response 2018; 16:1559325818761681. [PMID: 29686592 PMCID: PMC5904721 DOI: 10.1177/1559325818761681] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 01/30/2018] [Accepted: 01/30/2018] [Indexed: 11/29/2022] Open
Abstract
Paraquat (PQ) exposure is known as a risk factor for developing neurodegenerative diseases. Astrocytes are implicated and affected in neurodegenerative diseases and brain injuries, so it is suspected that PQ may impose detrimental effects on astrocytes function. Here, we present a study of the effects of PQ on synaptic function of astrocytes. Human astrocytes (HA1800) were separately treated with PQ at 200, 400, and 800 µmol/L for 12, 24, and 48 hours, respectively. The concentrations of membrane cholesterol, intracellular glutamate, and adenosine triphosphate (ATP) were assessed by measuring changes with Kits after PQ treatment. Expression levels of glial fibrillary acidic protein (GFAP) and apolipoprotein E (ApoE) were detected using Western blot method. The results indicated that astrocytes were highly susceptible to PQ showing astrogliosis characterized by enhanced GFAP expression (P < .05). The decreased cholesterol level and ApoE expression were observed in PQ-treated astrocytes and so were the decreased levels of glutamates and ATP in PQ-treated astrocytes. These results suggested that PQ exerted the detrimental effects on synaptic function of astrocytes, which may be involved in the progressive process of neurodegenerative disorders.
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Affiliation(s)
- Zheng Li
- Department of Toxicology, Public Health School, Harbin Medical University, Harbin, People's Republic of China
| | - Jing Zheng
- Department of Public Health Monitoring, Heilongjiang Provincial Centre for Disease Control and Prevention, Harbin, People's Republic of China
| | - Xiao-Feng Zhang
- Department of Toxicology, Public Health School, Harbin Medical University, Harbin, People's Republic of China
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18
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Lu E, Sarkar S, Raymick J, Paule MG, Gu Q. Decreased Mcl-1 protein level in the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice. Brain Res 2018; 1678:432-439. [DOI: 10.1016/j.brainres.2017.11.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/14/2017] [Accepted: 11/15/2017] [Indexed: 12/15/2022]
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19
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Wang XH, Souders CL, Zhao YH, Martyniuk CJ. Paraquat affects mitochondrial bioenergetics, dopamine system expression, and locomotor activity in zebrafish (Danio rerio). CHEMOSPHERE 2018; 191:106-117. [PMID: 29031050 DOI: 10.1016/j.chemosphere.2017.10.032] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Revised: 10/01/2017] [Accepted: 10/05/2017] [Indexed: 06/07/2023]
Abstract
The dipyridyl herbicide paraquat induces oxidative stress in cells and is implicated in adult neurodegenerative diseases. However, less is known about paraquat toxicity in early stages of vertebrate development. To address this gap, zebrafish (Danio rerio) embryos were exposed to 1, 10 and 100 μM paraquat for 96 h. Paraquat did not induce significant mortality nor deformity in embryos and larvae, but it did accelerate time to hatch. To evaluate whether mitochondrial respiration was related to earlier hatch times, oxygen consumption rate was measured in whole embryos. Maximal respiration of embryos exposed to 100 μM paraquat for 24 h was reduced by more than 70%, suggesting that paraquat negatively impacts mitochondrial bioenergetics in early development. Based upon this evidence for mitochondrial dysfunction, transcriptional responses of oxidative stress- and apoptosis-related genes were measured. Fish exposed to 1 μM paraquat showed higher expression levels of superoxide dismutase 2, heat shock protein 70, Bcl-2-associated X protein, and B-cell CLL/lymphoma 2a compared to control fish. No differences among groups were detected in larvae exposed to 10 and 100 μM paraquat, suggesting a non-monotonic response. We also measured endpoints related to larval behavior and dopaminergic signaling as paraquat is associated with degeneration of dopamine neurons. Locomotor activity was stimulated with 100 μM paraquat and dopamine transporter and dopamine receptor 3 mRNA levels were increased in larvae exposed to 1 μM paraquat, interpreted to be a compensatory response at lower concentrations. This study improves mechanistic understanding into the toxic actions of paraquat on early developmental stages.
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Affiliation(s)
- Xiao H Wang
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun, Jilin 130117, PR China; Center for Environmental and Human Toxicology, Department of Physiological Sciences, College of Veterinary Medicine, UF Genetics Institute, Interdisciplinary Program in Biomedical Sciences Neuroscience, University of Florida, Gainesville, FL 32611, USA
| | - Christopher L Souders
- Center for Environmental and Human Toxicology, Department of Physiological Sciences, College of Veterinary Medicine, UF Genetics Institute, Interdisciplinary Program in Biomedical Sciences Neuroscience, University of Florida, Gainesville, FL 32611, USA
| | - Yuan H Zhao
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun, Jilin 130117, PR China.
| | - Christopher J Martyniuk
- Center for Environmental and Human Toxicology, Department of Physiological Sciences, College of Veterinary Medicine, UF Genetics Institute, Interdisciplinary Program in Biomedical Sciences Neuroscience, University of Florida, Gainesville, FL 32611, USA.
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20
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Helley MP, Pinnell J, Sportelli C, Tieu K. Mitochondria: A Common Target for Genetic Mutations and Environmental Toxicants in Parkinson's Disease. Front Genet 2017; 8:177. [PMID: 29204154 PMCID: PMC5698285 DOI: 10.3389/fgene.2017.00177] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 11/01/2017] [Indexed: 12/15/2022] Open
Abstract
Parkinson's disease (PD) is a devastating neurological movement disorder. Since its first discovery 200 years ago, genetic and environmental factors have been identified to play a role in PD development and progression. Although genetic studies have been the predominant driving force in PD research over the last few decades, currently only a small fraction of PD cases can be directly linked to monogenic mutations. The remaining cases have been attributed to other risk associated genes, environmental exposures and gene-environment interactions, making PD a multifactorial disorder with a complex etiology. However, enormous efforts from global research have yielded significant insights into pathogenic mechanisms and potential therapeutic targets for PD. This review will highlight mitochondrial dysfunction as a common pathway involved in both genetic mutations and environmental toxicants linked to PD.
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Affiliation(s)
- Martin P. Helley
- Department of Environmental Health Sciences, Florida International University, Miami, FL, United States
| | - Jennifer Pinnell
- Department of Environmental Health Sciences, Florida International University, Miami, FL, United States
- Peninsula Schools of Medicine and Dentistry, Plymouth University, Plymouth, United Kingdom
| | - Carolina Sportelli
- Department of Environmental Health Sciences, Florida International University, Miami, FL, United States
- Peninsula Schools of Medicine and Dentistry, Plymouth University, Plymouth, United Kingdom
| | - Kim Tieu
- Department of Environmental Health Sciences, Florida International University, Miami, FL, United States
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Li F, Tian X, Zhan X, Wang B, Ding M, Pang H. Clathrin-Dependent Uptake of Paraquat into SH-SY5Y Cells and Its Internalization into Different Subcellular Compartments. Neurotox Res 2017; 32:204-217. [PMID: 28303546 DOI: 10.1007/s12640-017-9722-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 02/19/2017] [Accepted: 03/07/2017] [Indexed: 01/09/2023]
Abstract
The herbicide paraquat (PQ) is an exogenous toxin that allows the selective activation of dopaminergic neurons in the mesencephalon to induce injury and also causes its apoptosis in vitro. However, uptake mechanisms between PQ and neurons remain elusive. To address this issue, we undertook a study of PQ endocytosis in a dopaminergic SH-SY5Y cell line as well as explored the subsequent subcellular location and potential functional analysis of PQ. The PQ was found to bind the SH-SY5Y cell membrane and then became internalized via a clathrin-dependent pathway. PQ was internalized by many subcellular organelles in a time- and dose-dependent manner. Interestingly, the taken up PQ and secretogranin III (SCG3), which became dysregulated with PQ treatment that induced SH-SY5Y apoptosis in our previous study, colocalized in cytoplasmic vesicles. Taken together, our findings indicate that PQ is endocytosed by SH-SY5Y cells and that its multiple, subcellular localizations indicate PQ may potentially be involved in subcellular-level functions. More importantly, PQ distributing preferentially into SCG3-positive vesicles demonstrates its selective targeting which may affect SCG3 and cargoes carried by SCG3-positive vesicles. Therefore, it is reasonable to infer that PQ toxic insults may potentially interfere with neurotransmitter storage and transport associated with secretory granules.
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Affiliation(s)
- Fengrui Li
- School of Forensic Medicine, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, 110122, People's Republic of China.,Department of Forensic Medicine, Baotou Medical University, Baotou, People's Republic of China
| | - Xiaofei Tian
- School of Forensic Medicine, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, 110122, People's Republic of China.,Department of Forensic Medicine, Hebei North University, Zhangjiakou, People's Republic of China
| | - Xiaoni Zhan
- School of Forensic Medicine, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, 110122, People's Republic of China
| | - Baojie Wang
- School of Forensic Medicine, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, 110122, People's Republic of China
| | - Mei Ding
- School of Forensic Medicine, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, 110122, People's Republic of China
| | - Hao Pang
- School of Forensic Medicine, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, 110122, People's Republic of China.
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22
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Ockleford C, Adriaanse P, Berny P, Brock T, Duquesne S, Grilli S, Hernandez-Jerez AF, Bennekou SH, Klein M, Kuhl T, Laskowski R, Machera K, Pelkonen O, Pieper S, Smith R, Stemmer M, Sundh I, Teodorovic I, Tiktak A, Topping CJ, Wolterink G, Angeli K, Fritsche E, Hernandez-Jerez AF, Leist M, Mantovani A, Menendez P, Pelkonen O, Price A, Viviani B, Chiusolo A, Ruffo F, Terron A, Bennekou SH. Investigation into experimental toxicological properties of plant protection products having a potential link to Parkinson's disease and childhood leukaemia. EFSA J 2017; 15:e04691. [PMID: 32625422 PMCID: PMC7233269 DOI: 10.2903/j.efsa.2017.4691] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In 2013, EFSA published a literature review on epidemiological studies linking exposure to pesticides and human health outcome. As a follow up, the EFSA Panel on Plant Protection Products and their residues (PPR Panel) was requested to investigate the plausible involvement of pesticide exposure as a risk factor for Parkinson's disease (PD) and childhood leukaemia (CHL). A systematic literature review on PD and CHL and mode of actions for pesticides was published by EFSA in 2016 and used as background documentation. The Panel used the Adverse Outcome Pathway (AOP) conceptual framework to define the biological plausibility in relation to epidemiological studies by means of identification of specific symptoms of the diseases as AO. The AOP combines multiple information and provides knowledge of biological pathways, highlights species differences and similarities, identifies research needs and supports regulatory decisions. In this context, the AOP approach could help in organising the available experimental knowledge to assess biological plausibility by describing the link between a molecular initiating event (MIE) and the AO through a series of biologically plausible and essential key events (KEs). As the AOP is chemically agnostic, tool chemical compounds were selected to empirically support the response and temporal concordance of the key event relationships (KERs). Three qualitative and one putative AOP were developed by the Panel using the results obtained. The Panel supports the use of the AOP framework to scientifically and transparently explore the biological plausibility of the association between pesticide exposure and human health outcomes, identify data gaps, define a tailored testing strategy and suggests an AOP's informed Integrated Approach for Testing and Assessment (IATA). This publication is linked to the following EFSA Supporting Publications article: http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2017.EN-1190/full
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23
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Herraiz T. N-methyltetrahydropyridines and pyridinium cations as toxins and comparison with naturally-occurring alkaloids. Food Chem Toxicol 2016; 97:23-39. [DOI: 10.1016/j.fct.2016.08.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 07/22/2016] [Accepted: 08/05/2016] [Indexed: 02/06/2023]
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24
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Smeyne RJ, Breckenridge CB, Beck M, Jiao Y, Butt MT, Wolf JC, Zadory D, Minnema DJ, Sturgess NC, Travis KZ, Cook AR, Smith LL, Botham PA. Assessment of the Effects of MPTP and Paraquat on Dopaminergic Neurons and Microglia in the Substantia Nigra Pars Compacta of C57BL/6 Mice. PLoS One 2016; 11:e0164094. [PMID: 27788145 PMCID: PMC5082881 DOI: 10.1371/journal.pone.0164094] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 09/20/2016] [Indexed: 12/21/2022] Open
Abstract
The neurotoxicity of paraquat dichloride (PQ) was assessed in two inbred strains of 9- or 16-week old male C57BL/6 mice housed in two different laboratories and compared to the effects of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). PQ was administered by intraperitoneal injections; either once (20 mg/kg) or twice (10 mg/kg) weekly for 3 weeks, while MPTP-HCl was injected 4 times on a single day (20 mg/kg/dose). Brains were collected 8, 16, 24, 48, 96 or 168 hours after the last PQ treatment, and 48 or 168 hours after MPTP treatment. Dopamine neurons in the substantia nigra pars compacta (SNpc) were identified by antibodies to tyrosine hydroxylase (TH+) and microglia were identified using Iba-1 immunoreactivity. The total number of TH+ neurons and the number of resting and activated microglia in the SNpc at 168 hours after the last dose were estimated using model- or design-based stereology, with investigators blinded to treatment. In a further analysis, a pathologist, also blinded to treatment, evaluated the SNpc and/or striatum for loss of TH+ neurons (SNpc) or terminals (striatum), cell death (as indicated by amino cupric silver uptake, TUNEL and/or caspase 3 staining) and neuroinflammation (as indicated by Iba-1 and/or GFAP staining). PQ, administered either once or twice weekly to 9- or 16-week old mice from two suppliers, had no effect on the number of TH+ neurons or microglia in the SNpc, as assessed by two groups, each blinded to treatment, using different stereological methods. PQ did not induce neuronal cell loss or degeneration in the SNpc or striatum. Additionally, there was no evidence of apoptosis, microgliosis or astrogliosis. In MPTP-treated mice, the number of TH+ neurons in the SNpc was significantly decreased and the number of activated microglia increased. Histopathological assessment found degenerating neurons/terminals in the SNpc and striatum but no evidence of apoptotic cell death. MPTP activated microglia in the SNpc and increased the number of astrocytes in the SNpc and striatum.
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Affiliation(s)
- Richard Jay Smeyne
- St. Jude Children’s Research Hospital, Dept. of Developmental Neurobiology, 262 Danny Thomas Place, Memphis, TN 38105, United States of America
- * E-mail:
| | - Charles B. Breckenridge
- Syngenta Crop Protection, LLC, P.O. Box 18300, Greensboro, NC 27419–8300, United States of America
| | - Melissa Beck
- WIL Research Laboratories, LLC., Ashland, OH 44805, United States of America
| | - Yun Jiao
- St. Jude Children’s Research Hospital, Dept. of Developmental Neurobiology, 262 Danny Thomas Place, Memphis, TN 38105, United States of America
| | - Mark T. Butt
- Tox Path Specialists, LLC, 8747 Chestnut Grove Road, Frederick, MD 21701–2607, United States of America
| | - Jeffrey C. Wolf
- Experimental Pathology Laboratories, Inc., 45600 Terminal Drive, Sterling, VA 20166, United States of America
| | - Dan Zadory
- Experimental Pathology Laboratories, Inc., 45600 Terminal Drive, Sterling, VA 20166, United States of America
| | - Daniel J. Minnema
- Syngenta Crop Protection, LLC, P.O. Box 18300, Greensboro, NC 27419–8300, United States of America
| | - Nicholas C. Sturgess
- Syngenta Limited, Jealott's Hill International Research Centre, Bracknell, Berkshire, RG42 6EY, United Kingdom
| | - Kim Z. Travis
- Syngenta Limited, Jealott's Hill International Research Centre, Bracknell, Berkshire, RG42 6EY, United Kingdom
| | - Andrew R. Cook
- Syngenta Limited, Jealott's Hill International Research Centre, Bracknell, Berkshire, RG42 6EY, United Kingdom
| | - Lewis L. Smith
- University of Leicester, University Road, Leicester LE1 7RH, United Kingdom
| | - Philip A. Botham
- Syngenta Limited, Jealott's Hill International Research Centre, Bracknell, Berkshire, RG42 6EY, United Kingdom
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Neurotoxicity of paraquat and paraquat-induced mechanisms of developing Parkinson's disease. J Transl Med 2016; 96:1028-9. [PMID: 27562308 DOI: 10.1038/labinvest.2016.80] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Li B, He X, Sun Y, Li B. Developmental exposure to paraquat and maneb can impair cognition, learning and memory in Sprague-Dawley rats. MOLECULAR BIOSYSTEMS 2016; 12:3088-97. [PMID: 27460631 DOI: 10.1039/c6mb00284f] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Paraquat and maneb are identified environmental pollutants. Combined exposure to paraquat and maneb is a latent risk factor for many diseases, particularly those of the central nervous system, including Parkinson's disease and Alzheimer's disease. Hippocampus is the key structure in memory formation and babies are more sensitive to environmental stimuli than adults, so we investigated the neurotoxicity of paraquat and maneb on the hippocampi of rat pups. Female and male Sprague-Dawley rats were mated (female : male = 2 : 1) every night for a week. The gravid rats were randomly divided into three groups (one control and two experimental groups). A mixed solution of paraquat-maneb was administered twice a week by lavage at a dose of 10 or 15 mg kg(-1) bodyweight (containing 30 or 45 mg kg(-1) bodyweight maneb, respectively) from day 6 after pregnancy till ablactation. Maternal weight gain and offspring bodyweights were not affected by the drugs. However, behavioral tests showed that reaction latency and mistake frequency increased after treatment. Intuitively, we found significant changes in the hippocampal neurons in the morphological observation. Taking into account the interaction of the related genes in the cAMP-PKA-CREB pathway, we used a variety of methods to detect the gene and protein levels. Reduced expression of cAMP and related genes and proteins in the hippocampus and serum was also observed. These results indicate that PQ-MB stimulates cAMP to reduce the production of PKA, thus reducing the phosphorylation of CREB and inhibiting the activation of other elements (BDNF, C-JUN, and C-FOS). These changes lead to hippocampal damage and impaired abilities (learning, cognition, and memory). Our results demonstrate that PQ-MB induces hippocampal toxicity in the early life of rats, and they thus provide a theoretical foundation for further investigation of the bathypelagic mechanism involved and measures that can be taken to avoid PQ-MB neurotoxicity.
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Affiliation(s)
- Bai Li
- Department of Toxicology, College of Public Health, Harbin Medical University, Harbin, Heilongjiang Province 150081, P. R. China.
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Jiao Y, Dou Y, Lockwood G, Pani A, Jay Smeyne R. Acute Effects of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or Paraquat on Core Temperature in C57BL/6J Mice. JOURNAL OF PARKINSONS DISEASE 2016; 5:389-401. [PMID: 25633843 PMCID: PMC4923733 DOI: 10.3233/jpd-140424] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Background: MPTP and paraquat are two compounds that have been used to model Parkinson’s disease in mice. Previous studies in two non-traditional strains of mice have shown that a single dose of MPTP can induce changes in body temperature, while the effects of paraquat have not been examined. Examination of body temperature is important since small fluctuations in an animal’s core temperature can significantly affect drug metabolism, and if significant enough can even culminate in an animal’s death. Objective: To determine how external heating can alter the survival of C57BL/6J mice following MPTP administration. Methods: In this study, we examine the effects of MPTP (4×20 mg/kg, 2 hours apart) and paraquat (2×10 mg/kg/week for 3 weeks) on core temperature of C57BL/6J mice. Correlations of purine and catecholamine levels were also done in mice treated with MPTP. Results: We find that MPTP induces a significant hypothermia in C57BL/6J mice that reduces their core temperature below the limit of fatal hypothermia. Unlike MPTP, paraquat did not induce a significant hypothermia. Placement of animals on heating pads significantly abrogates the loss of core temperature. In both heated and non-heated conditions, mice treated with MPTP showed a significant depletion of ATP within 2 hours of administration in both striatum and SN that started to recover 2 hours after MPTP administration was complete. Striatal DA and DOPAC are significantly reduced starting 4–6 hours after MPTP. Conclusions: The fatal hypothermic effects of MPTP can be abrogated through use of external heating.
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Affiliation(s)
- Yun Jiao
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Yuchen Dou
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Georgina Lockwood
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN, USA.,Department of Biochemistry, University of Bath, Bath, UK
| | - Amar Pani
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Richard Jay Smeyne
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN, USA
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Multifactorial theory applied to the neurotoxicity of paraquat and paraquat-induced mechanisms of developing Parkinson's disease. J Transl Med 2016; 96:496-507. [PMID: 26829122 DOI: 10.1038/labinvest.2015.161] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 10/07/2015] [Accepted: 10/12/2015] [Indexed: 11/08/2022] Open
Abstract
Laboratory studies involving repeated exposure to paraquat (PQ) in different animal models can induce many of the pathological features of Parkinson's disease (PD), such as the loss of dopaminergic neurons in the nigrostriatal dopamine system. Epidemiological studies identify an increased risk of developing PD in human populations living in areas where PQ exposure is likely to occur and among workers lacking appropriate protective equipment. The mechanisms involved in developing PD may not be due to any single cause, but rather a multifactorial situation may exist where PQ exposure may cause PD in some circumstances. Multifactorial theory is adopted into this review that includes a number of sub-cellular mechanisms to explain the pathogenesis of PD. The theory is placed into an environmental context of chronic low-dose exposure to PQ that consequently acts as an oxidative stress inducer. Oxidative stress and the metabolic processes of PQ-inducing excitotoxicity, α-synuclein aggregate formation, autophagy, alteration of dopamine catabolism, and inactivation of tyrosine hydroxylase are positioned as causes for the loss of dopaminergic cells. The environmental context and biochemistry of PQ in soils, water, and organisms is also reviewed to identify potential routes that can lead to chronic rates of low-dose exposure that would replicate the type of response that is observed in animal models, epidemiological studies, and other types of laboratory investigations involving PQ exposure. The purpose of this review is to synthesize key relations and summarize hypotheses linking PD to PQ exposure by using the multifactorial approach. Recommendations are given to integrate laboratory methods to the environmental context as a means to improve on experimental design. The multifactorial approach is necessary for conducting valid tests of causal relations, for understanding of potential relations between PD and PQ exposure, and may prevent further delay in solving what has proven to be an evasive etiological problem.
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Association between Parkinson's Disease and Cigarette Smoking, Rural Living, Well-Water Consumption, Farming and Pesticide Use: Systematic Review and Meta-Analysis. PLoS One 2016; 11:e0151841. [PMID: 27055126 PMCID: PMC4824443 DOI: 10.1371/journal.pone.0151841] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 03/05/2016] [Indexed: 12/19/2022] Open
Abstract
Objective Bradford Hill’s viewpoints were used to conduct a weight-of-the-evidence assessment of the association between Parkinson’s disease (PD) and rural living, farming and pesticide use. The results were compared with an assessment based upon meta-analysis. For comparison, we also evaluated the association between PD and cigarette smoking as a “positive control” because a strong inverse association has been described consistently in the literature. Methods PubMed was searched systematically to identify all published epidemiological studies that evaluated associations between Parkinson’s disease (PD) and cigarette smoking, rural living, well-water consumption, farming and the use of pesticides, herbicides, insecticides, fungicides or paraquat. Studies were categorized into two study quality groups (Tier 1 or Tier 2); data were abstracted and a forest plot of relative risks (RRs) was developed for each risk factor. In addition, when available, RRs were tabulated for more highly exposed individuals compared with the unexposed. Summary RRs for each risk factor were calculated by meta-analysis of Tier 1, Tier 2 and all studies combined, with sensitivity analyses stratified by other study characteristics. Indices of between-study heterogeneity and evidence of reporting bias were assessed. Bradford Hill’s viewpoints were used to determine if a causal relationship between PD and each risk factor was supported by the weight of the evidence. Findings There was a consistent inverse (negative) association between current cigarette smoking and PD risk. In contrast, associations between PD and rural living, well-water consumption, farming and the use of pesticides, herbicides, insecticides, fungicides or paraquat were less consistent when assessed quantitatively or qualitatively. Conclusion The weight of the evidence and meta-analysis support the conclusion that there is a causal relationship between PD risk and cigarette smoking, or some unknown factor correlated with cigarette smoking. There may be risk factors associated with rural living, farming, pesticide use or well-water consumption that are causally related to PD, but the studies to date have not identified such factors. To overcome the limitations of research in this area, future studies will have to better characterize the onset of PD and its relationship to rural living, farming and exposure to pesticides.
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Dietary administration of diquat for 13 weeks does not result in a loss of dopaminergic neurons in the substantia nigra of C57BL/6J mice. Regul Toxicol Pharmacol 2015; 75:81-8. [PMID: 26683030 DOI: 10.1016/j.yrtph.2015.12.001] [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: 08/21/2015] [Revised: 11/30/2015] [Accepted: 12/01/2015] [Indexed: 11/24/2022]
Abstract
Male and female C57BL/6J mice were administered diquat dibromide (DQ∙Br2) in their diets at concentrations of 0 (control), 12.5 and 62.5 ppm for 13 weeks to assess the potential effects of DQ on the nigrostriatal dopaminergic system. Achieved dose levels at 62.5 ppm were 6.4 and 7.6 mg DQ (ion)/kg bw/day for males and females, respectively. A separate group of mice was administered 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) ip as a positive control. The comparative effects of DQ and MPTP on the substantia nigra pars compacta (SNpc) and/or striatum were assessed using neurochemical, neuropathological and stereological endpoints. Morphological and stereological assessments were performed by investigators who were "blinded" to dose group. DQ had no effect on striatal dopamine concentration or dopamine turnover. There was no evidence of neuronal degeneration, astrocytic or microglial activation, or a reduction in the number of tyrosine hydroxylase positive (TH(+)) neurons in the SNpc or neuronal processes in the striatum of DQ-treated mice. These results are consistent with the rapid clearance of DQ from the brain following a single dose of radiolabeled DQ. In contrast, MPTP-treated mice exhibited decreased striatal dopamine concentration, reduced numbers of TH(+) neurons in the SNpc, and neuropathological changes, including neuronal necrosis, as well as astrocytic and microglial activation in the striatum and SNpc.
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Impairment of striatal mitochondrial function by acute paraquat poisoning. J Bioenerg Biomembr 2015; 47:395-408. [PMID: 26350412 DOI: 10.1007/s10863-015-9624-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 08/31/2015] [Indexed: 10/23/2022]
Abstract
Mitochondria are essential for survival. Their primary function is to support aerobic respiration and to provide energy for intracellular metabolic pathways. Paraquat is a redox cycling agent capable of generating reactive oxygen species. The aim of the present study was to evaluate changes in cortical and striatal mitochondrial function in an experimental model of acute paraquat toxicity and to compare if the brain areas and the molecular mechanisms involved were similar to those observed after chronic exposure. Sprague-Dawley rats received paraquat (25 mg/Kg i.p.) or saline and were sacrificed after 24 h. Paraquat treatment decreased complex I and IV activity by 37 and 21 % respectively in striatal mitochondria. Paraquat inhibited striatal state 4 and state 3 KCN-sensitive respiration by 80 % and 62 % respectively, indicating a direct effect on respiratory chain. An increase of 2.2 fold in state 4 and 2.3 fold in state 3 in KCN-insensitive respiration was observed in striatal mitochondria from paraquat animals, suggesting that paraquat redox cycling also consumed oxygen. Paraquat treatment increased hydrogen peroxide production (150 %), TBARS production (42 %) and cardiolipin oxidation/depletion (12 %) in striatal mitochondria. Also, changes in mitochondrial polarization was induced after paraquat treatment. However, no changes were observed in any of these parameters in cortical mitochondria from paraquat treated-animals. These results suggest that paraquat treatment induced a clear striatal mitochondrial dysfunction due to both paraquat redox cycling reactions and impairment of the mitochondrial electron transport, causing oxidative damage. As a consequence, mitochondrial dysfunction could probably lead to alterations in cellular bioenergetics.
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Cook A, Breckenridge C, Sturgess N, Minnema D, Travis K, Botham P. Letter to the editor. Re: The perplexing paradox of paraquat: the case for host-based susceptibility and postulated neurodegenerative effects. J Biochem Mol Toxicol 2015; 28:289-90. [PMID: 25044315 DOI: 10.1002/jbt.21591_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Abstract
The central nervous system's extrapyramidal system provides involuntary motor control to the muscles of the head, neck, and limbs. Toxicants that affect the extrapyramidal system are generally clinically characterized by impaired motor control, which is usually the result of basal ganglionic dysfunction. A variety of extrapyramidal syndromes are recognized in humans and include Parkinson's disease, secondary parkinsonism, other degenerative diseases of the basal ganglia, and clinical syndromes that result in dystonia, dyskinesia, essential tremor, and other forms of tremor and chorea. This chapter briefly reviews the anatomy of the extrapyramidal system and discusses several naturally occurring and experimental models that target the mammalian (nonhuman) extrapyramidal system. Topics discussed include extrapyramidal syndromes associated with antipsychotic drugs, carbon monoxide, reserpine, cyanide, rotenone, paraquat, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), and manganese. In most cases, animals are used as experimental models to improve our understanding of the toxicity and pathogenesis of these agents. Another agent discussed in this chapter, yellowstar thistle poisoning in horses, however, represents an important spontaneous cause of parkinsonism that naturally occurs in animals. The central focus of the chapter is on animal models, especially the concordance between clinical signs, neurochemical changes, and neuropathology between animals and people.
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Affiliation(s)
- David Dorman
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA.
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34
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Pesticides exposure as etiological factors of Parkinson's disease and other neurodegenerative diseases—A mechanistic approach. Toxicol Lett 2014; 230:85-103. [PMID: 24503016 DOI: 10.1016/j.toxlet.2014.01.039] [Citation(s) in RCA: 242] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 12/06/2013] [Accepted: 01/27/2014] [Indexed: 12/12/2022]
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35
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Berry SC. Reproducibility in experimentation – the implications for regulatory toxicology. Toxicol Res (Camb) 2014. [DOI: 10.1039/c4tx00069b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Jones BC, Huang X, Mailman RB, Lu L, Williams RW. The perplexing paradox of paraquat: the case for host-based susceptibility and postulated neurodegenerative effects. J Biochem Mol Toxicol 2014; 28:191-7. [PMID: 24599642 PMCID: PMC4677573 DOI: 10.1002/jbt.21552] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 01/20/2014] [Accepted: 02/01/2014] [Indexed: 12/13/2022]
Abstract
Paraquat is an herbicide used extensively in agriculture and has also been proposed to be a risk factor for Parkinson's disease. To date, experimental, clinical, and epidemiological data on paraquat neurotoxicity have been equivocal. In this short review, we discuss some technical and biological mechanisms that contribute to inconsistencies regarding paraquat neurotoxicity. We hypothesize that individual genetic variations in susceptibility generate major differences in neurotoxic risk and functional outcome. Identifying these heritable sources of variation in host susceptibility, and their role in complex gene-environment interactions, is crucial to identify risk biomarkers and to devise better prevention and treatment for those exposed to paraquat and other potential neurotoxicants.
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Affiliation(s)
- Byron C Jones
- Department of Biobehavioral Health, The Pennsylvania State University, University Park, PA, USA; Department of Pharmacology, The Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA, USA.
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Effects of syringic acid on chronic MPTP/probenecid induced motor dysfunction, dopaminergic markers expression and neuroinflammation in C57BL/6 mice. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.biomag.2014.02.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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38
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Bortolotto JW, Cognato GP, Christoff RR, Roesler LN, Leite CE, Kist LW, Bogo MR, Vianna MR, Bonan CD. Long-term exposure to paraquat alters behavioral parameters and dopamine levels in adult zebrafish (Danio rerio). Zebrafish 2014; 11:142-53. [PMID: 24568596 DOI: 10.1089/zeb.2013.0923] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Chronic exposure to paraquat (Pq), a toxic herbicide, can result in Parkinsonian symptoms. This study evaluated the effect of the systemic administration of Pq on locomotion, learning and memory, social interaction, tyrosine hydroxylase (TH) expression, dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) levels, and dopamine transporter (DAT) gene expression in zebrafish. Adult zebrafish received an i.p. injection of either 10 mg/kg (Pq10) or 20 mg/kg (Pq20) of Pq every 3 days for a total of six injections. Locomotion and distance traveled decreased at 24 h after each injection in both treatment doses. In addition, both Pq10- and Pq20-treated animals exhibited differential effects on the absolute turn angle. Nonmotor behaviors were also evaluated, and no changes were observed in anxiety-related behaviors or social interactions in Pq-treated zebrafish. However, Pq-treated animals demonstrated impaired acquisition and consolidation of spatial memory in the Y-maze task. Interestingly, dopamine levels increased while DOPAC levels decreased in the zebrafish brain after both treatments. However, DAT expression decreased in the Pq10-treated group, and there was no change in the Pq20-treated group. The amount of TH protein showed no significant difference in the treated group. Our study establishes a new model to study Parkinson-associated symptoms in zebrafish that have been chronically treated with Pq.
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Affiliation(s)
- Josiane W Bortolotto
- 1 Programa de Pós-Graduação em Biologia Celular e Molecular, Laboratório de Neuroquímica e Psicofarmacologia, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul , Porto Alegre, Brazil
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Lacher SE, Gremaud JN, Skagen K, Steed E, Dalton R, Sugden KD, Cardozo-Pelaez F, Sherwin CMT, Woodahl EL. Absence of P-glycoprotein transport in the pharmacokinetics and toxicity of the herbicide paraquat. J Pharmacol Exp Ther 2014; 348:336-45. [PMID: 24297779 PMCID: PMC3912546 DOI: 10.1124/jpet.113.209791] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 11/26/2013] [Indexed: 01/25/2023] Open
Abstract
Genetic variation in the multidrug resistance gene ABCB1, which encodes the efflux transporter P-glycoprotein (P-gp), has been associated with Parkinson disease. Our goal was to investigate P-gp transport of paraquat, a Parkinson-associated neurotoxicant. We used in vitro transport models of ATPase activity, xenobiotic-induced cytotoxicity, transepithelial permeability, and rhodamine-123 inhibition. We also measured paraquat pharmacokinetics and brain distribution in Friend leukemia virus B-type (FVB) wild-type and P-gp-deficient (mdr1a(-/-)/mdr1b(-/-)) mice following 10, 25, 50, and 100 mg/kg oral doses. In vitro data showed that: 1) paraquat failed to stimulate ATPase activity; 2) resistance to paraquat-induced cytotoxicity was unchanged in P-gp-expressing cells in the absence or presence of P-gp inhibitors GF120918 [N-(4-[2-(1,2,3,4-tetrahydro-6,7-dimethoxy-2-isoquinolinyl)ethyl]-phenyl)-9,10-dihydro-5-methoxy-9-oxo-4-acridine carboxamide] and verapamil-37.0 [95% confidence interval (CI): 33.2-41.4], 46.2 (42.5-50.2), and 34.1 µM (31.2-37.2)-respectively; 3) transepithelial permeability ratios of paraquat were the same in P-gp-expressing and nonexpressing cells (1.55 ± 0.39 and 1.39 ± 0.43, respectively); and 4) paraquat did not inhibit rhodamine-123 transport. Population pharmacokinetic modeling revealed minor differences between FVB wild-type and mdr1a(-/-)/mdr1b(-/-) mice: clearances of 0.47 [95% confidence interval (CI): 0.42-0.52] and 0.78 l/h (0.58-0.98), respectively, and volume of distributions of 1.77 (95% CI: 1.50-2.04) and 3.36 liters (2.39-4.33), respectively; however, the change in clearance was in the opposite direction of what would be expected. It is noteworthy that paraquat brain-to-plasma partitioning ratios and total brain accumulation were the same across doses between FVB wild-type and mdr1a(-/-)/mdr1b(-/-) mice. These studies indicate that paraquat is not a P-gp substrate. Therefore, the association between ABCB1 pharmacogenomics and Parkinson disease is not attributed to alterations in paraquat transport.
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Affiliation(s)
- Sarah E Lacher
- Department of Biomedical and Pharmaceutical Sciences (S.E.L, K.S., E.S., R.D., F.C.-P, E.L.W.), Center for Environmental Health Sciences (S.E.L., F.C.-P.), Center for Biomolecular Structure and Dynamics (E.L.W.), Department of Chemistry (J.N.G., K.D.S.), University of Montana, Missoula, Montana; and Department of Pediatrics, University of Utah, Salt Lake City, Utah (C.M.T.S.)
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Allen JL, Liu X, Weston D, Conrad K, Oberdörster G, Cory-Slechta DA. Consequences of developmental exposure to concentrated ambient ultrafine particle air pollution combined with the adult paraquat and maneb model of the Parkinson's disease phenotype in male mice. Neurotoxicology 2014; 41:80-8. [PMID: 24486957 DOI: 10.1016/j.neuro.2014.01.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 01/20/2014] [Accepted: 01/21/2014] [Indexed: 10/25/2022]
Abstract
Current evidence suggests suceptibility of both the substantia nigra and striatum to exposure to components of air pollution. Further, air pollution has been associated with increased risk of PD diagnsosis in humans or PD-like pathology in animals. This study examined whether exposure of mice to concentrated ambient ultrafine particles (CAPS; <100nm diameter) during the first two weeks of life would alter susceptibility to induction of the Parkinson's disease phenyotype (PDP) in a pesticide-based paraquat and maneb (PQ+MB) model during adulthood utilizing i.p. injections of 10mg/kg PQ and 30mg/kg MB 2× per week for 6 weeks. Evidence of CAPS-induced enhancement of the PQ+MB PDP was limited primarily to delayed recovery of locomotor activity 24 post-injection of PQ+MB that could be related to alterations in striatal GABA inhibitory function. Absence of more extensive interactions might also reflect the finding that CAPS and PQ+MB appeared to differentially target the nigrostriatal dopamine and amino acid systems, with CAPS impacting striatum and PQ+MB impacting dopamine-glutamate function in midbrain; both CAPS and PQ+MB elevated glutamate levels in these specific regions, consistent with potential excitotoxicity. These findings demonstrate the ability of postnatal CAPS to produce locomotor dysfunction and dopaminergic and glutamateric changes, independent of PQ+MB, in brain regions involved in the PDP.
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Affiliation(s)
- Joshua L Allen
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - Xiufang Liu
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - Douglas Weston
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - Katherine Conrad
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - Günter Oberdörster
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
| | - Deborah A Cory-Slechta
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, NY 14642, USA.
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Minnema DJ, Travis KZ, Breckenridge CB, Sturgess NC, Butt M, Wolf JC, Zadory D, Beck MJ, Mathews JM, Tisdel MO, Cook AR, Botham PA, Smith LL. Dietary administration of paraquat for 13 weeks does not result in a loss of dopaminergic neurons in the substantia nigra of C57BL/6J mice. Regul Toxicol Pharmacol 2014; 68:250-8. [PMID: 24389362 DOI: 10.1016/j.yrtph.2013.12.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 12/23/2013] [Accepted: 12/25/2013] [Indexed: 10/25/2022]
Abstract
Several investigations have reported that mice administered paraquat dichloride (PQ·Cl2) by intraperitoneal injection exhibit a loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). In this study, male and female C57BL/6J mice were administered PQ·Cl2 in the diet at concentrations of 0 (control), 10, and 50ppm for a duration of 13weeks. A separate group of mice were administered 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) during week 12 as positive controls to produce a loss of dopaminergic neurons in the SNpc. The comparative effects of PQ and MPTP on the SNpc and/or striatum were assessed using neurochemical, neuropathological, and stereological endpoints. Morphological and stereological assessments were performed by investigators 'blinded' to the origin of the tissue. Neither dose of PQ·Cl2 (10 or 50 ppm in the diet) caused a loss of striatal dopamine or dopamine metabolite concentrations in the brains of mice. Pathological assessments of the SNpc and striatum showed no evidence of neuronal degeneration or astrocytic/microglial activation. Furthermore, the number of tyrosine hydroxylase-positive (TH(+)) neurons in the SNpc was not reduced in PQ-treated mice. In contrast, MPTP caused a decrease in striatal dopamine concentration, a reduction in TH(+) neurons in the SNpc, and significant pathological changes including astrocytic and microglial activation in the striatum and SNpc. The MPTP-induced effects were greater in males than in females. It is concluded that 13weeks of continuous dietary exposure of C57BL/6J mice to 50ppm PQ·Cl2 (equivalent to 10.2 and 15.6mg PQ ion/kg body weight/day for males and females, respectively) does not result in the loss of, or damage to, dopaminergic neurons in the SNpc.
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Affiliation(s)
- Daniel J Minnema
- Syngenta Crop Protection, LLC, P.O. Box 18300, Greensboro, NC 27419-8300, USA.
| | - Kim Z Travis
- Syngenta Limited, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK
| | | | - Nicholas C Sturgess
- Syngenta Limited, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK
| | - Mark Butt
- Tox Path Specialists, LLC, 8420 Gas House Pike, Frederick, MD 21701-2607, USA
| | - Jeffrey C Wolf
- Experimental Pathology Laboratories, Inc., 45600 Terminal Drive, Sterling, VA 20166, USA
| | - Dan Zadory
- Experimental Pathology Laboratories, Inc., 45600 Terminal Drive, Sterling, VA 20166, USA
| | | | - James M Mathews
- RTI International, 3040 Cornwallis Road, Research Triangle Park, NC 27709-2194, USA
| | - Merrill O Tisdel
- Syngenta Crop Protection, LLC, P.O. Box 18300, Greensboro, NC 27419-8300, USA
| | - Andrew R Cook
- Syngenta Limited, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK
| | - Philip A Botham
- Syngenta Limited, Jealott's Hill International Research Centre, Bracknell, Berkshire RG42 6EY, UK
| | - Lewis L Smith
- University of Leicester, University Road, Leicester, LE1 7RH, UK
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42
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Du G, Lewis MM, Sterling NW, Kong L, Chen H, Mailman RB, Huang X. Microstructural changes in the substantia nigra of asymptomatic agricultural workers. Neurotoxicol Teratol 2013; 41:60-4. [PMID: 24334261 DOI: 10.1016/j.ntt.2013.12.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 10/23/2013] [Accepted: 12/02/2013] [Indexed: 11/17/2022]
Abstract
Parkinson's disease (PD) is marked by the loss of dopamine neurons in the substantia nigra (SN). Although the exact etiology is unknown, sporadic PD is hypothesized to be a result of genetic susceptibility interacting with environmental insult. Epidemiological studies suggest that pesticide exposure is linked to higher PD risk, but there are no studies demonstrating SN changes with chronic pesticide exposure in human subjects. Thus, high resolution T2-weighted magnetic resonance imaging (MRI) and diffusion tensor (DTI) images were obtained from 12 agricultural workers with chronic pesticide exposure, 12 controls, and 12 PD subjects. Neither controls nor pesticide-exposed subjects, had any parkinsonian symptoms. Exposure history to pesticides was assessed by a structured questionnaire. DTI measures in the SN, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD), were obtained for all subjects and compared among groups. Compared to controls, PD patients showed the expected significant changes in all DTI measurements in the SN. The pesticide-exposed subjects, compared to controls, had significantly lower FA values (p=0.022, after multiple comparisons correction), but no significant differences in RD, MD, or AD measures. The study is the first to demonstrate microstructural changes in the SN of human subjects with chronic pesticide exposure. The changes detected by MRI may mark "one of the hits" leading to PD, and underlie the increased risk of PD in pesticide users found in epidemiological studies. Further human studies assisted by these imaging markers may be useful in understanding the etiology of PD.
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Affiliation(s)
- Guangwei Du
- Departments of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA
| | - Mechelle M Lewis
- Departments of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA; Departments of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA
| | - Nicholas W Sterling
- Departments of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA
| | - Lan Kong
- Departments of Public Health Sciences, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA
| | - Honglei Chen
- National Institute of Environmental Health Sciences, Research Triangle Park, NC 27705, USA
| | - Richard B Mailman
- Departments of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA; Departments of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA
| | - Xuemei Huang
- Departments of Neurology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA; Departments of Pharmacology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA; Departments of Radiology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA; Departments of Neurosurgery, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA; Departments of Kinesiology, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA; Departments of Bioengineering, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, PA 17033, USA.
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43
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Jones BC, Lu L, Williams RW, Unger EL, Yin L. Response to Breckenridge et al. (2013). Neurotoxicology 2013; 38:23-4. [PMID: 23727076 DOI: 10.1016/j.neuro.2013.05.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 05/15/2013] [Indexed: 01/27/2023]
Affiliation(s)
- Byron C Jones
- The Pennsylvania State University, University Park, PA, USA.
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