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Tan MY, Wu S, Zhu SX, Jiang LH. Association between exposure to organophosphorus pesticide and suicidal ideation among U.S. adults: A population-based study. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 281:116572. [PMID: 38896903 DOI: 10.1016/j.ecoenv.2024.116572] [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: 04/15/2024] [Revised: 05/27/2024] [Accepted: 06/05/2024] [Indexed: 06/21/2024]
Abstract
OBJECTIVE This study aims to investigate the potential link between exposure to organophosphorus pesticides (OPPs) and suicidal ideation (SI) among adults. METHODS This study encompassed four cycles of the National Health and Nutrition Examination Survey (NHANES), involving 5244 participants aged 20 and above. SI was assessed using the Patient Health Questionnaire-9. The levels of exposure to OPPs were estimated by analyzing concentrations of OPP metabolites in urine samples. Multivariate logistic regression models were used to explore the association between exposure to each OPP and SI. Stratified analyses and interaction tests were conducted across various groups, including pairwise combinations of gender and age, as well as body mass index, smoking status, hypertension, and diabetes. Weighted Quantile Sum (WQS) regression and Bayesian Kernel Machine Regression (BKMR) models were applied to assess the cumulative impact of exposure to the four OPPs on SI, along with their respective contributions. Additionally, the potential interactions among these four OPPs were evaluated. RESULTS Multivariate logistic regression revealed that only dimethylthiophosphate (DMTP) among OPPs demonstrated a statistically significant positive association with SI [OR: 1.18; 95 % CI: 1.02-1.37]. Stratified analyses indicated that the influence of OPPs on SI was particularly pronounced in young and older men. The WQS regression analysis revealed a statistically significant association between the mixed metabolites of OPPs and SI [OR = 1.10, 95 % CI: 1.04-1.16], with DMTP (weighted 0.63) contributing the most. Furthermore, the BKMR model supported a positive trend in the overall impact of these OPP metabolites on SI, displaying notable individual exposure-response relationships for DMTP (PIP: 0.77). CONCLUSIONS Our study suggests an association between exposure to DMTP and an increased risk of SI. Specifically, young adult males and older males appear particularly susceptible to the effects of OPP exposure.
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Affiliation(s)
- Mo-Yao Tan
- Chengdu Integrated TCM and Western Medicine Hospital, Chengdu, Sichuan, China
| | - Shan Wu
- Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Si-Xuan Zhu
- Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Li-Hai Jiang
- Chengdu Integrated TCM and Western Medicine Hospital, Chengdu, Sichuan, China.
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Yadav B, Kaur S, Yadav A, Verma H, Kar S, Sahu BK, Pati KR, Sarkar B, Dhiman M, Mantha AK. Implications of organophosphate pesticides on brain cells and their contribution toward progression of Alzheimer's disease. J Biochem Mol Toxicol 2024; 38:e23660. [PMID: 38356323 DOI: 10.1002/jbt.23660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 01/04/2024] [Accepted: 01/18/2024] [Indexed: 02/16/2024]
Abstract
The most widespread neurodegenerative disorder, Alzheimer's disease (AD) is marked by severe behavioral abnormalities, cognitive and functional impairments. It is inextricably linked with the deposition of amyloid β (Aβ) plaques and tau protein in the brain. Loss of white matter, neurons, synapses, and reactive microgliosis are also frequently observed in patients of AD. Although the causative mechanisms behind the neuropathological alterations in AD are not fully understood, they are likely influenced by hereditary and environmental factors. The etiology and pathogenesis of AD are significantly influenced by the cells of the central nervous system, namely, glial cells and neurons, which are directly engaged in the transmission of electrical signals and the processing of information. Emerging evidence suggests that exposure to organophosphate pesticides (OPPs) can trigger inflammatory responses in glial cells, leading to various cascades of events that contribute to neuroinflammation, neuronal damage, and ultimately, AD pathogenesis. Furthermore, there are striking similarities between the biomarkers associated with AD and OPPs, including neuroinflammation, oxidative stress, dysregulation of microRNA, and accumulation of toxic protein aggregates, such as amyloid β. These shared markers suggest a potential mechanistic link between OPP exposure and AD pathology. In this review, we attempt to address the role of OPPs on altered cell physiology of the brain cells leading to neuroinflammation, mitochondrial dysfunction, and oxidative stress linked with AD pathogenesis.
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Affiliation(s)
- Bharti Yadav
- Department of Zoology, Central University of Punjab, Bathinda, Punjab, India
| | - Sharanjot Kaur
- Department of Microbiology, Central University of Punjab, Bathinda, Punjab, India
| | - Anuradha Yadav
- Department of Zoology, Central University of Punjab, Bathinda, Punjab, India
| | - Harkomal Verma
- Department of Zoology, Central University of Punjab, Bathinda, Punjab, India
| | - Swastitapa Kar
- Department of Zoology, Central University of Punjab, Bathinda, Punjab, India
| | - Binit Kumar Sahu
- Department of Zoology, Central University of Punjab, Bathinda, Punjab, India
| | - Kumari Riya Pati
- Department of Zoology, Central University of Punjab, Bathinda, Punjab, India
| | - Bibekanada Sarkar
- Department of Zoology, Central University of Punjab, Bathinda, Punjab, India
| | - Monisha Dhiman
- Department of Microbiology, Central University of Punjab, Bathinda, Punjab, India
| | - Anil Kumar Mantha
- Department of Zoology, Central University of Punjab, Bathinda, Punjab, India
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3
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Ireland D, Rabeler C, Gong T, Collins EMS. Bioactivation and detoxification of organophosphorus pesticides in freshwater planarians shares similarities with humans. Arch Toxicol 2022; 96:3233-3243. [PMID: 36173421 PMCID: PMC10729609 DOI: 10.1007/s00204-022-03387-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 09/21/2022] [Indexed: 11/02/2022]
Abstract
Organophosphorus pesticides (OPs) are a chemically diverse class of insecticides that inhibit acetylcholinesterase (AChE). Many OPs require bioactivation to their active oxon form via cytochrome P450 to effectively inhibit AChE. OP toxicity can be mitigated by detoxification reactions performed by carboxylesterase and paraoxonase. The relative extent of bioactivation to detoxification varies among individuals and between species, leading to differential susceptibility to OP toxicity. Because of these species differences, it is imperative to characterize OP metabolism in model systems used to assess OP toxicity. We have shown that the asexual freshwater planarian Dugesia japonica is a suitable model to assess OP neurotoxicity and developmental neurotoxicity via rapid, automated testing of adult and developing organisms in parallel using morphological and behavioral endpoints. D. japonica has two cholinesterase enzymes with intermediate properties between AChE and butyrylcholinesterase that are sensitive to OP inhibition. Here, we demonstrate that D. japonica contains the major OP metabolic machinery to be a relevant model for OP neurotoxicity studies. Adult and regenerating D. japonica can bioactivate chlorpyrifos and diazinon into their respective oxons. Significant AChE inhibition was only observed after in vivo metabolic activation but not when the parent OPs were directly added to planarian homogenate using the same concentrations and timing. Using biochemical assays, we found that D. japonica has both carboxylesterase (24 nmol/(min*mg protein)) and paraoxonase (60 pmol/(min*mg protein)) activity. We show that planarian carboxylesterase activity is distinct from cholinesterase activity using benzil and tacrine. These results further support the use of D. japonica for OP toxicity studies.
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Affiliation(s)
| | | | - TaiXi Gong
- Department of Biology, Swarthmore College, Swarthmore, PA, USA
| | - Eva-Maria S Collins
- Department of Biology, Swarthmore College, Swarthmore, PA, USA.
- Department of Physics and Astronomy, Swarthmore College, Swarthmore, PA, USA.
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Center of Excellence in Environmental Toxicology, University of Pennsylvania, Philadelphia, PA, USA.
- Department of Physics, University of California San Diego, La Jolla, CA, USA.
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Ireland D, Zhang S, Bochenek V, Hsieh JH, Rabeler C, Meyer Z, Collins EMS. Differences in neurotoxic outcomes of organophosphorus pesticides revealed via multi-dimensional screening in adult and regenerating planarians. FRONTIERS IN TOXICOLOGY 2022; 4:948455. [PMID: 36267428 PMCID: PMC9578561 DOI: 10.3389/ftox.2022.948455] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 08/25/2022] [Indexed: 11/07/2022] Open
Abstract
Organophosphorus pesticides (OPs) are a chemically diverse class of commonly used insecticides. Epidemiological studies suggest that low dose chronic prenatal and infant exposures can lead to life-long neurological damage and behavioral disorders. While inhibition of acetylcholinesterase (AChE) is the shared mechanism of acute OP neurotoxicity, OP-induced developmental neurotoxicity (DNT) can occur independently and/or in the absence of significant AChE inhibition, implying that OPs affect alternative targets. Moreover, different OPs can cause different adverse outcomes, suggesting that different OPs act through different mechanisms. These findings emphasize the importance of comparative studies of OP toxicity. Freshwater planarians are an invertebrate system that uniquely allows for automated, rapid and inexpensive testing of adult and developing organisms in parallel to differentiate neurotoxicity from DNT. Effects found only in regenerating planarians would be indicative of DNT, whereas shared effects may represent neurotoxicity. We leverage this unique feature of planarians to investigate potential differential effects of OPs on the adult and developing brain by performing a comparative screen to test 7 OPs (acephate, chlorpyrifos, dichlorvos, diazinon, malathion, parathion and profenofos) across 10 concentrations in quarter-log steps. Neurotoxicity was evaluated using a wide range of quantitative morphological and behavioral readouts. AChE activity was measured using an Ellman assay. The toxicological profiles of the 7 OPs differed across the OPs and between adult and regenerating planarians. Toxicological profiles were not correlated with levels of AChE inhibition. Twenty-two "mechanistic control compounds" known to target pathways suggested in the literature to be affected by OPs (cholinergic neurotransmission, serotonin neurotransmission, endocannabinoid system, cytoskeleton, adenyl cyclase and oxidative stress) and 2 negative controls were also screened. When compared with the mechanistic control compounds, the phenotypic profiles of the different OPs separated into distinct clusters. The phenotypic profiles of adult vs. regenerating planarians exposed to the OPs clustered differently, suggesting some developmental-specific mechanisms. These results further support findings in other systems that OPs cause different adverse outcomes in the (developing) brain and build the foundation for future comparative studies focused on delineating the mechanisms of OP neurotoxicity in planarians.
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Affiliation(s)
- Danielle Ireland
- Department of Biology, Swarthmore College, Swarthmore, PA, United States
| | - Siqi Zhang
- Department of Bioengineering, University of California San Diego, La Jolla, CA, United States
| | - Veronica Bochenek
- Department of Biology, Swarthmore College, Swarthmore, PA, United States
| | - Jui-Hua Hsieh
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Durham, NC, United States
| | - Christina Rabeler
- Department of Biology, Swarthmore College, Swarthmore, PA, United States
| | - Zane Meyer
- Department of Engineering, Swarthmore College, Swarthmore, PA, United States,Department of Computer Science, Swarthmore College, Swarthmore, PA, United States
| | - Eva-Maria S. Collins
- Department of Biology, Swarthmore College, Swarthmore, PA, United States,Department of Physics and Astronomy, Swarthmore College, Swarthmore, PA, United States,Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States,Center of Excellence in Environmental Toxicology, University of Pennsylvania, Philadelphia, PA, United States,Department of Physics, University of California San Diego, La Jolla, CA, United States,*Correspondence: Eva-Maria S. Collins,
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Mosier JA, Hybart RL, Lewis AM, Alugubelly N, Mohammed AN, Carr RL. Inhibition of Serum Esterases in Juvenile Rats Repeatedly Exposed to Low Levels of Chlorpyrifos. INTERNATIONAL JOURNAL OF SCIENTIFIC RESEARCH IN ENVIRONMENTAL SCIENCE AND TOXICOLOGY 2022; 5:10.15226/2572-3162/5/1/00133. [PMID: 36118291 PMCID: PMC9477121 DOI: 10.15226/2572-3162/5/1/00133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Chlorpyrifos (CPF) is an organophosphorus insecticide that has gained significant attention cue to the reported toxicity associated with developmental exposure. While the canonical mechanism of toxicity of CPF involves the inhibition of brain acetylcholinesterase (AChE), we have reported that exposure of juvenile rats to levels of CPF that do not yield any inhibition of brain AChE results in neurobehavioral alterations at later ages. However, it is unclear what effect exposure to these low levels of CPF has on blood esterase activities which are frequently used not only as biomarkers of exposure but also to set exposure levels in risk assessment. To determine this, male and female rat pups were exposed orally from postnatal day 10 to 16 to either corn oil (vehicle) or 0.5, 0.75, or 1.0 mg/kg CPF. At 12 h after the final exposure, serum cholinesterase (ChE), butyrylcholinesterase (BChE), and carboxylesterase (CES), and red blood cell (RBC) and brain AChE activities were determined. There were no differences between sexes in either the controls or individual treatments for all enzymes. Only the highest dosage of 1.0 mg/kg CPF yielded significant brain AChE inhibition (22-24%) but all dosages significantly inhibited the blood esterases with inhibition being highest with serum CES (65-85%) followed by serum BChE (57-76%), RBC AChE (35-65%), and then serum ChE (16-32%). Our data verify that blood esterases are inhibited at dosages of CPF that alter neurobehavioral performance in the absence of effects on brain AChE activity.
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Affiliation(s)
- Jenna A. Mosier
- Center for Environmental Health Sciences, Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Rachel L. Hybart
- Center for Environmental Health Sciences, Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Aubrey M. Lewis
- Center for Environmental Health Sciences, Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Navatha Alugubelly
- Center for Environmental Health Sciences, Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Afzaal N. Mohammed
- Center for Environmental Health Sciences, Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Russell L. Carr
- Center for Environmental Health Sciences, Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
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Li Y, Wang X, Feary McKenzie J, 't Mannetje A, Cheng S, He C, Leathem J, Pearce N, Sunyer J, Eskenazi B, Yeh R, Aylward LL, Donovan G, Mueller JF, Douwes J. Pesticide exposure in New Zealand school-aged children: Urinary concentrations of biomarkers and assessment of determinants. ENVIRONMENT INTERNATIONAL 2022; 163:107206. [PMID: 35395578 DOI: 10.1016/j.envint.2022.107206] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 03/21/2022] [Accepted: 03/22/2022] [Indexed: 06/14/2023]
Abstract
This study aimed to assess pesticide exposure and its determinants in children aged 5-14 years. Urine samples (n = 953) were collected from 501 participating children living in urban areas (participant n = 300), rural areas but not on a farm (n = 76), and living on a farm (n = 125). The majority provided two samples, one in the high and one in the low spraying season. Information on diet, lifestyle, and demographic factors was collected by questionnaire. Urine was analysed for 20 pesticide biomarkers by GC-MS/MS and LC-MS/MS. Nine analytes were detected in > 80% of samples, including six organophosphate insecticide metabolites (DMP, DMTP, DEP, DETP, TCPy, PNP), two pyrethroid insecticide metabolites (3-PBA, trans-DCCA), and one herbicide (2,4-D). The highest concentration was measured for TCPy (median 13 μg/g creatinine), a metabolite of chlorpyrifos and triclopyr, followed by DMP (11 μg/g) and DMTP (3.7 μg/g). Urine metabolite levels were generally similar or low compared to those reported for other countries, while relatively high for TCPy and pyrethroid metabolites. Living on a farm was associated with higher TCPy levels during the high spray season. Living in rural areas, dog ownership and in-home pest control were associated with higher levels of pyrethroid metabolites. Urinary concentrations of several pesticide metabolites were higher during the low spraying season, possibly due to consumption of imported fruits and vegetables. Organic fruit consumption was not associated with lower urine concentrations, but consumption of organic food other than fruit or vegetables was associated with lower concentrations of TCPy in the high spray season. In conclusion, compared to other countries such as the U.S., New Zealand children had relatively high exposures to chlorpyrifos/triclopyr and pyrethroids. Factors associated with exposure included age, season, area of residence, diet, in-home pest control, and pets.
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Affiliation(s)
- Yan Li
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland 4102, Australia
| | - Xianyu Wang
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland 4102, Australia.
| | - Jean Feary McKenzie
- Centre for Public Health Research, Massey University. PO Box 756, Wellington 6140, New Zealand
| | - Andrea 't Mannetje
- Centre for Public Health Research, Massey University. PO Box 756, Wellington 6140, New Zealand
| | - Soo Cheng
- Centre for Public Health Research, Massey University. PO Box 756, Wellington 6140, New Zealand
| | - Chang He
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland 4102, Australia
| | - Janet Leathem
- School of Psychology, Massey University, PO Box 756, Wellington 6140, New Zealand
| | - Neil Pearce
- Department of Medical Statistics, London School of Hygiene and Tropical Medicine. London WC1E 7HT, UK
| | - Jordi Sunyer
- Barcelona Institute for Global Health (ISGlobal), Barcelona, Catalonia, Spain
| | - Brenda Eskenazi
- Center for Environmental Research and Community Health (CERCH), School of Public Health, University of California,1995 University Ave, Berkeley, CA 94720, United States
| | - Ruby Yeh
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland 4102, Australia
| | - Lesa L Aylward
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland 4102, Australia; Summit Toxicology, LLP, 22044, Falls Church, VA, USA
| | - Geoffrey Donovan
- Centre for Public Health Research, Massey University. PO Box 756, Wellington 6140, New Zealand; USDA Forest Service, PNW Research Station, Portland, OR, USA
| | - Jochen F Mueller
- QAEHS, Queensland Alliance for Environmental Health Sciences, The University of Queensland, 20 Cornwall Street, Woolloongabba, Queensland 4102, Australia
| | - Jeroen Douwes
- Centre for Public Health Research, Massey University. PO Box 756, Wellington 6140, New Zealand
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Hawkey AB, Pippen E, Kenou B, Holloway Z, Slotkin TA, Seidler FJ, Levin ED. Persistent neurobehavioral and neurochemical anomalies in middle-aged rats after maternal diazinon exposure. Toxicology 2022; 472:153189. [PMID: 35452779 PMCID: PMC9655883 DOI: 10.1016/j.tox.2022.153189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/13/2022] [Accepted: 04/15/2022] [Indexed: 11/17/2022]
Abstract
Diazinon is an organophosphate pesticide that has a history of wide use. Developmental exposures to organophosphates lead to neurobehavioral changes that emerge early in life and can persist into adulthood. However, preclinical studies have generally evaluated changes through young adulthood, whereas the persistence or progression of deficits into middle age remain poorly understood. The current study evaluated the effects of maternal diazinon exposure on behavior and neurochemistry in middle age, at 1 year postpartum, comparing the results to our previous studies of outcomes at adolescence and in young adulthood (4 months of age) (Hawkey 2020). Female rats received 0, 0.5 or 1.0 mg/kg/day of diazinon via osmotic minipump throughout gestation and into the postpartum period. The offspring were tested on a battery of locomotor, affective, and cognitive tests at young adulthood and during middle age. Some of the neurobehavioral consequences of developmental DZN seen during adolescence and young adulthood faded with continued aging, whereas other neurobehavioral effects emerged with aging. At middle age, the rats showed few locomotor effects, in contrast to the locomotor hyperactivity that had been observed in adolescence. Notably, though, DZN exposure during development impaired reference memory performance in middle-aged males, an effect that had not been seen in the younger animals. Likewise, middle-aged females exposed to DZN showed deficient attentional accuracy, an effect not seen in young adults. Across adulthood, the continued potential for behavioral defects was associated with altered dopaminergic function, characterized by enhanced dopamine utilization that was regionally-selective (striatum but not frontal/parietal cortex). This study shows that the neurobehavioral impairments from maternal low dose exposure to diazinon not only persist, but may continue to evolve as animals enter middle age.
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Affiliation(s)
- Andrew B Hawkey
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, USA
| | - Erica Pippen
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, USA
| | - Bruny Kenou
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, USA
| | - Zade Holloway
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, USA
| | - Theodore A Slotkin
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, USA
| | - Frederic J Seidler
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, USA
| | - Edward D Levin
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, USA.
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Sarrouilhe D, Defamie N, Mesnil M. Is the Exposome Involved in Brain Disorders through the Serotoninergic System? Biomedicines 2021; 9:1351. [PMID: 34680468 PMCID: PMC8533279 DOI: 10.3390/biomedicines9101351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 09/17/2021] [Accepted: 09/23/2021] [Indexed: 11/24/2022] Open
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) is a biogenic monoamine acting as a neurotransmitter in the central nervous system (CNS), local mediator in the gut, and vasoactive agent in the blood. It has been linked to a variety of CNS functions and is implicated in many CNS and psychiatric disorders. The high comorbidity between some neuropathies can be partially understood by the fact that these diseases share a common etiology involving the serotoninergic system. In addition to its well-known functions, serotonin has been shown to be a mitogenic factor for a wide range of normal and tumor cells, including glioma cells, in vitro. The developing CNS of fetus and newborn is particularly susceptible to the deleterious effects of neurotoxic substances in our environment, and perinatal exposure could result in the later development of diseases, a hypothesis known as the developmental origin of health and disease. Some of these substances affect the serotoninergic system and could therefore be the source of a silent pandemic of neurodevelopmental toxicity. This review presents the available data that are contributing to the appreciation of the effects of the exposome on the serotoninergic system and their potential link with brain pathologies (neurodevelopmental, neurodegenerative, neurobehavioral disorders, and glioblastoma).
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Affiliation(s)
- Denis Sarrouilhe
- Laboratoire de Physiologie Humaine, Faculté de Médecine et Pharmacie, 6 Rue de la Milétrie, Bât D1, TSA 51115, CEDEX 09, 86073 Poitiers, France
| | - Norah Defamie
- Laboratoire STIM, ERL7003 CNRS-Université de Poitiers, 1 Rue G. Bonnet–TSA 51106, CEDEX 09, 86073 Poitiers, France; (N.D.); (M.M.)
| | - Marc Mesnil
- Laboratoire STIM, ERL7003 CNRS-Université de Poitiers, 1 Rue G. Bonnet–TSA 51106, CEDEX 09, 86073 Poitiers, France; (N.D.); (M.M.)
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9
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Boyda J, Hawkey AB, Holloway ZR, Trevisan R, Di Giulio RT, Levin ED. The organophosphate insecticide diazinon and aging: Neurobehavioral and mitochondrial effects in zebrafish exposed as embryos or during aging. Neurotoxicol Teratol 2021; 87:107011. [PMID: 34224825 PMCID: PMC8440393 DOI: 10.1016/j.ntt.2021.107011] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 06/25/2021] [Accepted: 06/28/2021] [Indexed: 11/18/2022]
Abstract
Organophosphate (OP) compounds comprise one of the most widely used classes of insecticides worldwide. OPs have been shown to have negative human health impacts, particularly developmental neurotoxicity. However, neurotoxic impacts in later adulthood and during the aging process are relatively uncharacterized. The present study examined diazinon (DZN), an OP, to determine the neurobehavioral consequences, in addition to mitochondrial dysfunction on a macroscale (whole organism basal respiration) and on a microscale (whole organ mitochondrial respiration), using zebrafish (ZF) as a model. One group of 14-month-old adult ZF were exposed acutely as adults (0.4, 1.25, and 4.0 μM) for five days and tested as adults, and another group was exposed developmentally 5-120 h post-fertilization (70, 210, and 700 nM) and tested at larval, adolescent, adult, and aging life stages. ZF exposed acutely as adults did not display many significant neurobehavioral impacts or mitochondrial dysfunction. Conversely, the embryonically exposed ZF showed altered behavioral functions at each stage of life which emerged and attenuated as fish transitioned from each developmental stage to the next. Mitochondrial oxygen consumptions measurement results for developmentally DZN exposed ZF showed significant increases in the low and middle dose groups in organs such as the brain and testes. Overall, there is an indication that early developmental exposure to DZN had continuing adverse neurobehavioral and cellular consequences throughout their lives well into adulthood and aging periods.
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Affiliation(s)
- Jonna Boyda
- Nicholas School of the Environment, Duke University, Durham, NC, USA
| | - Andrew B Hawkey
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Duke University, Durham, NC, USA
| | - Zade R Holloway
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Duke University, Durham, NC, USA
| | - Rafael Trevisan
- Nicholas School of the Environment, Duke University, Durham, NC, USA
| | | | - Edward D Levin
- Nicholas School of the Environment, Duke University, Durham, NC, USA; Department of Psychiatry and Behavioral Sciences, School of Medicine, Duke University, Durham, NC, USA.
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10
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Slotkin TA, Skavicus S, Levin ED, Seidler FJ. Paternal Δ9-Tetrahydrocannabinol Exposure Prior to Mating Elicits Deficits in Cholinergic Synaptic Function in the Offspring. Toxicol Sci 2021; 174:210-217. [PMID: 32077955 DOI: 10.1093/toxsci/kfaa004] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Little attention has been paid to the potential impact of paternal marijuana use on offspring brain development. We administered Δ9-tetrahydrocannabinol (THC, 0, 2, or 4 mg/kg/day) to male rats for 28 days. Two days after the last THC treatment, the males were mated to drug-naïve females. We then assessed the impact on development of acetylcholine (ACh) systems in the offspring, encompassing the period from the onset of adolescence (postnatal day 30) through middle age (postnatal day 150), and including brain regions encompassing the majority of ACh terminals and cell bodies. Δ9-Tetrahydrocannabinol produced a dose-dependent deficit in hemicholinium-3 binding, an index of presynaptic ACh activity, superimposed on regionally selective increases in choline acetyltransferase activity, a biomarker for numbers of ACh terminals. The combined effects produced a persistent decrement in the hemicholinium-3/choline acetyltransferase ratio, an index of impulse activity per nerve terminal. At the low THC dose, the decreased presynaptic activity was partially compensated by upregulation of nicotinic ACh receptors, whereas at the high dose, receptors were subnormal, an effect that would exacerbate the presynaptic defect. Superimposed on these effects, either dose of THC also accelerated the age-related decline in nicotinic ACh receptors. Our studies provide evidence for adverse effects of paternal THC administration on neurodevelopment in the offspring and further demonstrate that adverse impacts of drug exposure on brain development are not limited to effects mediated by the embryonic or fetal chemical environment, but rather that vulnerability is engendered by exposures occurring prior to conception, involving the father as well as the mother.
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Affiliation(s)
| | | | - Edward D Levin
- Department of Psychiatry & Behavioral Sciences, Duke University Medical Center, Durham, North Carolina
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11
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Persistent proteomic changes in glutamatergic and GABAergic signaling in the amygdala of adolescent rats exposed to chlorpyrifos as juveniles. Neurotoxicology 2021; 85:234-244. [PMID: 34058248 DOI: 10.1016/j.neuro.2021.05.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 04/23/2021] [Accepted: 05/24/2021] [Indexed: 12/25/2022]
Abstract
Chlorpyrifos (CPF) remains one of the most widely used organophosphorus insecticides (OPs) despite the concerns about its developmental neurotoxicity. Developmental exposure to CPF has long-lasting negative impacts, including abnormal emotional behaviors. These negative impacts are observed at exposure levels do not cause inhibition of acetylcholinesterase, the canonical target of OPs. Exposure to CPF at these levels inhibits the endocannabinoid metabolizing enzyme fatty acid amide hydrolase (FAAH) but it is not clear what the persistent effects of this inhibition are. To investigate this, male rat pups were exposed orally to either corn oil, 0.75 mg/kg CPF, or 0.02 mg/kg PF-04457845 (PF; a specific inhibitor of FAAH) daily from postnatal day 10 (PND10) - PND16. This dosage of CPF does not inhibit brain cholinesterase activity but inhibits FAAH activity. On PND38 (adolescence), the protein expression in the amygdala was determined using a label-free shotgun proteomic approach. The analysis of control vs CPF and control vs PF led to the identification of 44 and 142 differentially regulated proteins, respectively. Gene ontology enrichment analysis revealed that most of the proteins with altered expression in both CPF and PF treatment groups were localized in the synapse-related regions, such as presynaptic membrane, postsynaptic density, and synaptic vesicle. The different biological processes affected by both treatment groups included persistent synaptic potentiation, glutamate receptor signaling, protein phosphorylation, and chemical synaptic transmission. These results also indicated disturbances in the balance between glutamatergic (↓ Glutamate AMPA receptor 2, ↓ Excitatory amino acid transporter 2, and ↑ vesicular glutamate transporter 2) and GABAergic signaling (↑ GABA transporter 3 and ↑ glutamate decarboxylase 2). This imbalance could play a role in the abnormal emotional behavior that we have previously reported. These results suggest that there is a similar pattern of expression between CPF and PF, and both these chemicals can persistently alter emotional behavior as a consequence of inhibition of FAAH.
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12
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Oh JH, Yoo JR, Ko SY, Kang JH, Lee SK, Jeong W, Seong GM, Lee HJ, Song SW. Relationship Between Sleep Duration and Suicidal Ideation Among Farmers: Safety for Agricultural Injuries of Farmers Cohort Study of Jeju, Korea. Saf Health Work 2020; 12:102-107. [PMID: 33732534 PMCID: PMC7940138 DOI: 10.1016/j.shaw.2020.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 09/15/2020] [Accepted: 10/08/2020] [Indexed: 10/24/2022] Open
Abstract
Background This study was conducted to identify the association between sleep duration and suicidal ideation among farmers in Korea. Methods We used Safety for Agricultural Injuries of Farmers cohort data collected from September 2015 to June 2018, which was an agricultural survey on the health and behaviors of adult farmers in Jeju island, Korea. Results A total of 964 participants were included in the analysis, and 3.7% of them were identified with having suicidal ideation. The frequencies of average daily sleep duration of <6 h (short sleep), 6-8 h (normal sleep), and >8 h (long sleep) were 24.4%, 70%, and 5.6%, respectively. Multivariate analyses revealed that short sleep duration was significantly associated with suicidal ideation compared with normal sleep duration (odds ratio = 2.49, 95% confidence interval = 1.07-5.77). Conclusion Our findings suggest that short sleep duration in farmers result in higher suicidal ideation. Because individuals who have suicidal ideation often commit suicide, careful monitoring is required to prevent suicide in farmers with short sleep duration.
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Affiliation(s)
- Jung-Hwan Oh
- Department of Neurology, Jeju National University College of Medicin and Graduate School of Medicine, Jeju, South Korea.,Center for Farmers' Safety and Health at Jeju National University Hospital, Jeju, South Korea
| | - Jeong Rae Yoo
- Department of Internal Medicine, Jeju National University College of Medicine and Graduate School of Medicine, Jeju, South Korea.,Center for Farmers' Safety and Health at Jeju National University Hospital, Jeju, South Korea
| | - Seo Young Ko
- Department of Emergency Medicine, Jeju National University Hospital, Jeju, South Korea.,Center for Farmers' Safety and Health at Jeju National University Hospital, Jeju, South Korea
| | - Jeong Ho Kang
- Department of Emergency Medicine, Jeju National University College of Medicine and Graduate School of Medicine, Jeju, South Korea.,Center for Farmers' Safety and Health at Jeju National University Hospital, Jeju, South Korea
| | - Sung Kgun Lee
- Department of Emergency Medicine, Jeju National University College of Medicine and Graduate School of Medicine, Jeju, South Korea.,Center for Farmers' Safety and Health at Jeju National University Hospital, Jeju, South Korea
| | - Wooseong Jeong
- Division of Rheumatology, Department of Internal Medicine, Jeju National University Hospital, Jeju, South Korea.,Center for Farmers' Safety and Health at Jeju National University Hospital, Jeju, South Korea
| | - Gil Myeong Seong
- Department of Internal Medicine, Jeju National University College of Medicine and Graduate School of Medicine, Jeju, South Korea.,Center for Farmers' Safety and Health at Jeju National University Hospital, Jeju, South Korea
| | - Hyun Jung Lee
- Department of Physical Medicine and Rehabilitation, Jeju National University Hospital, Jeju, South Korea.,Center for Farmers' Safety and Health at Jeju National University Hospital, Jeju, South Korea
| | - Sung Wook Song
- Department of Emergency Medicine, Jeju National University College of Medicine and Graduate School of Medicine, Jeju, South Korea.,Center for Farmers' Safety and Health at Jeju National University Hospital, Jeju, South Korea
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13
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Carr RL, Alugubelly N, de Leon K, Loyant L, Mohammed AN, Patterson ME, Ross MK, Rowbotham NE. Inhibition of fatty acid amide hydrolase by chlorpyrifos in juvenile rats results in altered exploratory and social behavior as adolescents. Neurotoxicology 2020; 77:127-136. [PMID: 31931040 DOI: 10.1016/j.neuro.2020.01.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 12/31/2019] [Accepted: 01/07/2020] [Indexed: 12/26/2022]
Abstract
The organophosphorus insecticide chlorpyrifos (CPF) is suspected to cause developmental neurotoxicity in children leading to long term effects. Developmental exposure of rat pups to CPF at low levels disrupts degradation of the brain endocannabinoids through the inhibition of fatty acid amide hydrolase (FAAH) and decreases the reactivity of juvenile rats in an emergence test. In this study, we further investigated the effects of developmental CPF exposure on behavior but also included exposure to PF-04457845, a specific inhibitor of FAAH, for comparison of behavior altered by FAAH inhibition with behavior altered by CPF. Ten day old rat pups were exposed orally either to 0.5, 0.75, or 1.0 mg/kg CPF or 0.02 mg/kg PF-04457845 daily for 7 days. In an open field (day 23), the high CPF and PF-04457845 groups exhibited increased motor activity but no differences in the time spent in the field's center. In an elevated plus maze (day 29), all treatment groups had increased open arm activity but ethological behaviors associated with anxiety were not altered. Behaviors in the maze associated with increased general activity and exploratory drive were increased. Social interactions (day 36) were measured and all treatment groups exhibited increased levels of play behavior. The similarities in behavior between PF-04457845 and CPF suggest that enhanced endocannabinoid signaling during the exposure period plays a role in the persistent alteration of behavior observed following developmental CPF exposure.
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Affiliation(s)
- Russell L Carr
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA.
| | - Navatha Alugubelly
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Kathryne de Leon
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Louise Loyant
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Afzaal N Mohammed
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - M Elizabeth Patterson
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Matthew K Ross
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Nicole E Rowbotham
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
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14
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Gestational and perinatal exposure to diazinon causes long-lasting neurobehavioral consequences in the rat. Toxicology 2019; 429:152327. [PMID: 31704166 DOI: 10.1016/j.tox.2019.152327] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 09/16/2019] [Accepted: 10/30/2019] [Indexed: 02/08/2023]
Abstract
Diazinon is a widely-used organophosphate pesticide. Pulsatile exposure to diazinon during neonatal development has previously been shown cause long-term neurobehavioral impairments in rats. However, the effects of chronic low concentration exposures during perinatal development remain unclear. This experiment evaluated such effects in Sprague-Dawley rats by implanting osmotic pumps in breeder females prior to conception (N = 13-15 litters per condition) which then delivered chronic, zero order kinetic low-level infusions of 0, 114 or 228 ug/day of diazinon throughout pregnancy. One male and one female from each litter was assessed with a battery of behavioral tests that continued from four weeks of age into adulthood. Litter was used as the unit of variance for the analysis of variance test of significance, with sex as a within litter factor. Diazinon treatment condition was the between subjects factor and time or sessions were repeated measures. Chronic diazinon exposure from pre-mating until the neonatal period caused a significant (p < 0.05) increase in percent of time spent on the open arms of the elevated plus maze, an index of risk-taking behavior. Gestational and lactational diazinon exposure also caused a significant (p < 0.05) degree of hyperactivity in the Figure-8 apparatus during adolescence, specifically affecting the early part of the hour-long test session. This effect had dissipated by the time the rats reached adulthood. Diazinon exposure also caused a significant impairment in novel object recognition, a test of cognitive function. Offspring exposed to 228 ug/day diazinon (p < 0.05) showed significantly less preference for the novel vs. familiar object than controls during the first five minutes of the novel object recognition test.
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15
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Slotkin TA, Skavicus S, Ko A, Levin ED, Seidler FJ. Perinatal diazinon exposure compromises the development of acetylcholine and serotonin systems. Toxicology 2019; 424:152240. [PMID: 31251962 DOI: 10.1016/j.tox.2019.152240] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 06/20/2019] [Accepted: 06/24/2019] [Indexed: 10/26/2022]
Abstract
Organophosphate pesticides are developmental neurotoxicants. We gave diazinon via osmotic minipumps implanted into dams prior to conception, with exposure continued into the second postnatal week, at doses (0.5 or 1 mg/kg/day) that did not produce detectable brain cholinesterase inhibition. We evaluated the impact on acetylcholine (ACh) and serotonin (5-hydroxytryptamine, 5HT) systems in brain regions from adolescence through full adulthood. Diazinon produced deficits in presynaptic ACh activity with regional and sex selectivity: cerebrocortical regions and the hippocampus were affected to a greater extent than were the striatum, midbrain or brainstem, and females were more sensitive than males. Diazinon also reduced nicotinic ACh receptors and 5HT1A receptors, with the same regional and sex preferences. These patterns were similar to those of diazinon given in a much more restricted period (postnatal day 1-4) but were of greater magnitude and consistency; this suggests that the brain is vulnerable to diazinon over a wide developmental window. Diazinon's effects differed from those of the related organophosphate, chlorpyrifos, with regard to regional and sex selectivity, and more importantly, to the effects on receptors: chlorpyrifos upregulates nicotinic ACh receptors and 5HT receptors, effects that compensate for the presynaptic ACh deficits. Diazinon can thus be expected to have worse neurodevelopmental outcomes than chlorpyrifos. Further, the disparities between diazinon and chlorpyrifos indicate the problems of predicting the developmental neurotoxicity of organophosphates based on a single compound, and emphasize the inadequacy of cholinesterase inhibition as an index of safety.
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Affiliation(s)
- Theodore A Slotkin
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA.
| | - Samantha Skavicus
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Ashley Ko
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Edward D Levin
- Department of Psychiatry & Behavioral Sciences, Duke University Medical Center, Durham, NC 27710, USA
| | - Frederic J Seidler
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA
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16
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Cartier C, Warembourg C, Monfort C, Rouget F, Limon G, Durand G, Cordier S, Saint-Amour D, Chevrier C. Children’s contrast sensitivity function in relation to organophosphate insecticide prenatal exposure in the mother-child PELAGIE cohort. Neurotoxicology 2018; 67:161-168. [DOI: 10.1016/j.neuro.2018.05.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 05/15/2018] [Accepted: 05/16/2018] [Indexed: 01/11/2023]
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17
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Neuroreflex control of cardiovascular function is impaired after acute poisoning with chlorpyrifos, an organophosphorus insecticide: Possible short and long term clinical implications. Toxicology 2018; 398-399:13-22. [PMID: 29471072 DOI: 10.1016/j.tox.2018.02.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 01/29/2018] [Accepted: 02/15/2018] [Indexed: 02/07/2023]
Abstract
Although it is well-established that severe poisoning by organophosphorus (OP) compounds strongly affects the cardiorespiratory system, the effects of sub-lethal exposure to these compounds on the neural control of cardiovascular function are poorly explored. The aim of this study was to evaluate the effects of acute sub-lethal exposure to chlorpyrifos (CPF), a commonly used OP insecticide, on three basic reflex mechanisms involved in blood pressure regulation, the peripheral chemoreflex, the baroreflex and the Bezold-Jarisch reflex. Adult male Wistar rats were injected intraperitoneally with a single dose of CPF (30 mg/kg) or saline (0.9%). 24 h after injections, cardiovascular reflexes were tested in awake rats. Potassium cyanide (KCN) and phenylbiguanide (PBG) were injected intravenously to activate the chemoreflex and the Bezold-Jarisch reflex, respectively. The baroreflex was activated by phenylephrine and sodium nitroprusside infusions. Blood samples were taken for measurements of butyrylcholinesterase (BChE) activity while acetylcholinesterase (AChE) activity was measured in brainstem samples. Animals treated with CPF presented signs of intoxication such as ataxia, tremor, lacrimation, salivation, tetany, urination and defecation. The hypertensive and the bradycardic responses of the chemoreflex as well as the hypotensive and bradycardic responses of the Bezold-Jarisch reflex were attenuated in CPF treated animals (P < 0.05). Concerning the baroreflex responses, CPF treatment reduced the bradycardia plateau, the range and the gain of the reflex (P < 0.05). Plasma BChE and brainstem AChE were both reduced significantly after CPF treatment (P < 0.05). Our results showed that acute sub-lethal exposure to CPF impairs the cardiovascular responses of homeostatic and defensive cardiovascular reflexes. These effects are associated with a marked inhibition of plasma BChE and brainstem AChE.
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18
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do Nascimento CP, Maretto GX, Marques GLM, Passamani LM, Abdala AP, Schenberg LC, Beijamini V, Sampaio KN. Methamidophos, an Organophosphorus Insecticide, Induces Pro-aggressive Behaviour in Mice. Neurotox Res 2017; 32:398-408. [PMID: 28540662 PMCID: PMC5750394 DOI: 10.1007/s12640-017-9750-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 05/08/2017] [Accepted: 05/10/2017] [Indexed: 10/19/2022]
Abstract
Although evidence indicates that exposure to organophosphorus (OP) pesticides induces neurobehavioral disorders, little is known about the effects of OP on aggressive behaviour. Our study investigated the effects of repeated exposure to an OP pesticide, methamidophos, on the isolation-induced aggressive behaviour in mice. Forty seven male mice were individually housed for a month. Socially isolated animals were then confronted with a standard non-isolated opponent for 15 min (pre-treatment trial), and the latency and frequency of aggressive and general exploratory behaviours were recorded. Based on the presence of attack behaviour in the pre-treatment trial, mice were classified as isolation-induced aggressive and non-aggressive. All mice were then treated for 7 days with methamidophos (3.5 mg/kg/day, n = 22, intraperitoneal (i.p.)) or saline (1 mL/kg/day, control group, n = 25, i.p.), and a second trial was performed. Repeated exposure to methamidophos induced attack behaviour in non-aggressive mice. The treatment with methamidophos also decreased plasma butyrylcholinesterase and brain acetylcholinesterase activity. These results suggest that methamidophos has a pro-aggressive effect on socially isolated mice.
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Affiliation(s)
- Cristina Paula do Nascimento
- Department of Pharmaceutical Sciences, Health Sciences Center, Federal University of Espírito Santo, Av. Marechal Campos, 1468, Maruípe, Vitória, ES, 29043-900, Brazil
| | - Gabriella Xavier Maretto
- Department of Physiological Sciences, UFES, Av. Marechal Campos, 1468, Maruípe, Vitória, ES, Brazil
| | - Graziany Leite Moreira Marques
- Department of Pharmaceutical Sciences, Health Sciences Center, Federal University of Espírito Santo, Av. Marechal Campos, 1468, Maruípe, Vitória, ES, 29043-900, Brazil
| | - Luciana Mesquita Passamani
- Department of Pharmaceutical Sciences, Health Sciences Center, Federal University of Espírito Santo, Av. Marechal Campos, 1468, Maruípe, Vitória, ES, 29043-900, Brazil
| | - Ana Paula Abdala
- School of Physiology and Pharmacology, Medical Sciences Building, University of Bristol, Bristol, BS8 1TD, UK
| | - Luiz Carlos Schenberg
- Department of Physiological Sciences, UFES, Av. Marechal Campos, 1468, Maruípe, Vitória, ES, Brazil
| | - Vanessa Beijamini
- Department of Pharmaceutical Sciences, Health Sciences Center, Federal University of Espírito Santo, Av. Marechal Campos, 1468, Maruípe, Vitória, ES, 29043-900, Brazil
| | - Karla Nívea Sampaio
- Department of Pharmaceutical Sciences, Health Sciences Center, Federal University of Espírito Santo, Av. Marechal Campos, 1468, Maruípe, Vitória, ES, 29043-900, Brazil.
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Slotkin TA, Skavicus S, Seidler FJ. Diazinon and parathion diverge in their effects on development of noradrenergic systems. Brain Res Bull 2017; 130:268-273. [PMID: 28235599 DOI: 10.1016/j.brainresbull.2017.02.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 02/08/2017] [Accepted: 02/10/2017] [Indexed: 10/20/2022]
Abstract
Organophosphate pesticides elicit developmental neurotoxicity through mechanisms over and above their shared property as cholinesterase inhibitors. We compared the consequences of neonatal exposure (postnatal days PN1-4) to diazinon or parathion on development of norepinephrine systems in rat brain, using treatments designed to produce equivalent effects on cholinesterase, straddling the threshold for barely-detectable inhibition. Norepinephrine levels were measured throughout development from the immediate posttreatment period (PN5), to early adolescence (PN30), young adulthood (PN60) and full adulthood (PN100); we assessed multiple brain regions containing all the major noradrenergic synaptic projections. Diazinon elicited a significant overall deficit of norepinephrine, whereas parathion produced a net increase. The effects were not immediately apparent (PN5) but rather emerged over the course of development, indicating that the organophosphate effects represent alteration of the trajectory of development, not just continuance of an initial injury. There were no comparable effects on β-adrenergic receptors, indicating that the presynaptic changes were not an adaptation to an underlying, primary effect on postsynaptic receptor signaling. Because we used the cholinesterase inhibition benchmark, the absolute dose of diazinon was much higher than that of parathion, since the latter is a more potent cholinesterase inhibitor. Our results are consistent with the growing evidence that the various organophosphates can differ in their impact on brain development and that consequently, the cholinesterase benchmark is an inadequate predictor of adverse neurodevelopmental effects.
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Affiliation(s)
- Theodore A Slotkin
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA.
| | - Samantha Skavicus
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA
| | - Frederic J Seidler
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA
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20
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Silva JG, Boareto AC, Schreiber AK, Redivo DDB, Gambeta E, Vergara F, Morais H, Zanoveli JM, Dalsenter PR. Chlorpyrifos induces anxiety-like behavior in offspring rats exposed during pregnancy. Neurosci Lett 2017; 641:94-100. [PMID: 28130185 DOI: 10.1016/j.neulet.2017.01.053] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 01/19/2017] [Accepted: 01/23/2017] [Indexed: 12/27/2022]
Abstract
Chlorpyrifos is a pesticide, member of the organophosphate class, widely used in several countries to manage insect pests on many agricultural crops. Currently, chlorpyrifos health risks are being reevaluated due to possible adverse effects, especially on the central nervous system. The aim of this study was to investigate the possible action of this pesticide on the behaviors related to anxiety and depression of offspring rats exposed during pregnancy. Wistar rats were treated orally with chlorpyrifos (0.01, 0.1, 1 and 10mg/kg/day) on gestational days 14-20. Male offspring behavior was evaluated on post-natal days 21 and 70 by the elevated plus-maze test, open field test and forced swimming test. The results demonstrated that exposure to 0.1, 1 or 10mg/kg/day of chlorpyrifos could induce anxiogenic-like, but not depressive-like behavior at post-natal day 21, without causing fetal toxicity. This effect was reversed on post-natal day 70.
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Affiliation(s)
- Jonas G Silva
- Department of Chemistry and Biology, Federal Technological University of Paraná, Curitiba, Paraná 81280-340, Brazil; Department of Pharmacology, Federal University of Paraná, Curitiba, Paraná 81540-990 Brazil.
| | - Ana C Boareto
- Department of Pharmacology, Federal University of Paraná, Curitiba, Paraná 81540-990 Brazil
| | - Anne K Schreiber
- Department of Pharmacology, Federal University of Paraná, Curitiba, Paraná 81540-990 Brazil
| | - Daiany D B Redivo
- Department of Pharmacology, Federal University of Paraná, Curitiba, Paraná 81540-990 Brazil
| | - Eder Gambeta
- Department of Pharmacology, Federal University of Paraná, Curitiba, Paraná 81540-990 Brazil
| | - Fernanda Vergara
- Department of Pharmacology, Federal University of Paraná, Curitiba, Paraná 81540-990 Brazil
| | - Helen Morais
- Department of Pharmacology, Federal University of Paraná, Curitiba, Paraná 81540-990 Brazil
| | - Janaína M Zanoveli
- Department of Pharmacology, Federal University of Paraná, Curitiba, Paraná 81540-990 Brazil
| | - Paulo R Dalsenter
- Department of Pharmacology, Federal University of Paraná, Curitiba, Paraná 81540-990 Brazil
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Rauh VA, Margolis AE. Research Review: Environmental exposures, neurodevelopment, and child mental health - new paradigms for the study of brain and behavioral effects. J Child Psychol Psychiatry 2016; 57:775-93. [PMID: 26987761 PMCID: PMC4914412 DOI: 10.1111/jcpp.12537] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/05/2016] [Indexed: 12/23/2022]
Abstract
BACKGROUND Environmental exposures play a critical role in the genesis of some child mental health problems. METHODS We open with a discussion of children's vulnerability to neurotoxic substances, changes in the distribution of toxic exposures, and cooccurrence of social and physical exposures. We address trends in prevalence of mental health disorders, and approaches to the definition of disorders that are sensitive to the subtle effects of toxic exposures. We suggest broadening outcomes to include dimensional measures of autism spectrum disorders, attention-deficit hyperactivity disorder, and child learning capacity, as well as direct assessment of brain function. FINDINGS We consider the impact of two important exposures on children's mental health: lead and pesticides. We argue that longitudinal research designs may capture the cascading effects of exposures across biological systems and the full-range of neuropsychological endpoints. Neuroimaging is a valuable tool for observing brain maturation under varying environmental conditions. A dimensional approach to measurement may be sensitive to subtle subclinical toxic effects, permitting the development of exposure-related profiles and testing of complex functional relationships between brain and behavior. Questions about the neurotoxic effects of chemicals become more pressing when viewed through the lens of environmental justice. CONCLUSIONS Reduction in the burden of child mental health disorders will require longitudinal study of neurotoxic exposures, incorporating dimensional approaches to outcome assessment, and measures of brain function. Research that seeks to identify links between toxic exposures and mental health outcomes has enormous public health and societal value.
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Affiliation(s)
- Virginia A Rauh
- Heilbrunn Department of Population and Family Health, Mailman School of Public Health, Columbia University, New York, NY, USA
- Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Amy E Margolis
- Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, New York, NY, USA
- Department of Child and Adolescent Psychiatry, Columbia University, New York, NY, USA
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22
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Cartier C, Warembourg C, Le Maner-Idrissi G, Lacroix A, Rouget F, Monfort C, Limon G, Durand G, Saint-Amour D, Cordier S, Chevrier C. Organophosphate Insecticide Metabolites in Prenatal and Childhood Urine Samples and Intelligence Scores at 6 Years of Age: Results from the Mother-Child PELAGIE Cohort (France). ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:674-80. [PMID: 26394442 PMCID: PMC4858392 DOI: 10.1289/ehp.1409472] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 09/17/2015] [Indexed: 05/22/2023]
Abstract
BACKGROUND Several studies suggest that exposure to organophosphate insecticides (OP) during pregnancy impairs neurodevelopment in children. OBJECTIVES We evaluated associations between biomarkers of prenatal and postnatal OP exposure and cognitive function of 6-year-olds in a French longitudinal birth cohort. METHODS In 2002-2006, the PELAGIE mother-child cohort enrolled pregnant women from Brittany. For a random subcohort, we measured nonspecific dialkylphosphate metabolites (DAP) of OP in one maternal urine sample, collected before 19 weeks' gestation, and in one urine sample collected from their 6-year-old children. Six subtests of the Wechsler Intelligence Scale for Children, 4th edition (WISC-IV) were administered when the children were 6 years of age to evaluate cognitive function (n = 231). Linear regression models controlling for factors including maternal intelligence and the Home Observation for Measurement of the Environment score were used. RESULTS WISC-IV scores were not significantly associated with prenatal or childhood total DAP metabolites. WISC verbal comprehension score was significantly higher in association with the highest maternal urinary concentrations of diethylphosphate (DE) metabolites (5.5; 95% CI: 0.8, 10.3 for > 13.2 nmol/L vs. < LOQ), whereas WISC working memory score was significantly lower in association with the highest urinary concentrations of DE metabolites at age 6 years (-3.6; 95% CI: -7.8, -0.6 for > 11.1 nmol/L vs. < LOD). CONCLUSION We found no evidence that prenatal OP exposure adversely affected cognitive function in 6-year-olds, perhaps because of the population's socioeconomic status, which was higher than in previous studies, though other causal and noncausal explanations are also possible. The negative association between WISC score and concurrent DE urinary concentrations requires replication by longitudinal studies investigating childhood OP exposure. CITATION Cartier C, Warembourg C, Le Maner-Idrissi G, Lacroix A, Rouget F, Monfort C, Limon G, Durand G, Saint-Amour D, Cordier S, Chevrier C. 2016. Organophosphate insecticide metabolites in prenatal and childhood urine samples and intelligence scores at 6 years of age: results from the mother-child PELAGIE cohort (France). Environ Health Perspect 124:674-680; http://dx.doi.org/10.1289/ehp.1409472.
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Affiliation(s)
- Chloé Cartier
- INSERM U1085-IRSET, Université Rennes I, Rennes, France
- Département de psychologie, Université du Québec à Montréal, Montréal, Québec, Canada
| | | | - Gaïd Le Maner-Idrissi
- Centre de Recherches en Psychologie, Cognition et communication (CRPCC EA 1285), Université Rennes 2, Rennes, France
| | - Agnès Lacroix
- Centre de Recherches en Psychologie, Cognition et communication (CRPCC EA 1285), Université Rennes 2, Rennes, France
| | - Florence Rouget
- INSERM U1085-IRSET, Université Rennes I, Rennes, France
- ”Bien Naître en Ille et Vilaine” network, Rennes, France
| | | | | | | | - Dave Saint-Amour
- Département de psychologie, Université du Québec à Montréal, Montréal, Québec, Canada
- Centre de recherche et département d’ophtalmologie, CHU Sainte-Justine, Montréal, Québec, Canada
| | | | - Cécile Chevrier
- INSERM U1085-IRSET, Université Rennes I, Rennes, France
- Address correspondence to C. Chevrier, INSERM U1085-IRSET, Avenue du Prof. Léon Bernard, CS74312, 35043 RENNES Cedex. Telephone: (33) 223236126. E-mail:
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Stallones L, Beseler CL. Assessing the connection between organophosphate pesticide poisoning and mental health: A comparison of neuropsychological symptoms from clinical observations, animal models and epidemiological studies. Cortex 2016; 74:405-16. [DOI: 10.1016/j.cortex.2015.10.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 10/01/2015] [Accepted: 10/05/2015] [Indexed: 01/08/2023]
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Decreased anxiety in juvenile rats following exposure to low levels of chlorpyrifos during development. Neurotoxicology 2015; 59:183-190. [PMID: 26642910 DOI: 10.1016/j.neuro.2015.11.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 11/11/2015] [Accepted: 11/25/2015] [Indexed: 11/22/2022]
Abstract
Exposure to chlorpyrifos (CPF) during the late preweanling period in rats inhibits the endocannabinoid metabolizing enzymes fatty acid hydrolase (FAAH) and monoacylglycerol lipase (MAGL), resulting in accumulation of their respective substrates anandamide (AEA) and 2-arachidonylglycerol (2-AG). This occurs at 1.0mg/kg, but at a lower dosage (0.5mg/kg) only FAAH and AEA are affected with no measurable inhibition of either cholinesterase (ChE) or MAGL. The endocannabinoid system plays a vital role in nervous system development and may be an important developmental target for CPF. The endocannabinoid system plays an important role in the regulation of anxiety and, at higher dosages, developmental exposure to CPF alters anxiety-like behavior. However, it is not clear whether exposure to low dosages of CPF that do not inhibit ChE will cause any persistent effects on anxiety-like behavior. To determine if this occurs, 10-day old rat pups were exposed daily for 7 days to either corn oil or 0.5, 0.75, or 1.0mg/kg CPF by oral gavage. At 12h following the last CPF administration, 1.0mg/kg resulted in significant inhibition of FAAH, MAGL, and ChE, whereas 0.5 and 0.75mg/kg resulted in significant inhibition of only FAAH. AEA levels were significantly elevated in all three treatment groups as were palmitoylethanolamide and oleoylethanolamide, which are also substrates for FAAH. 2-AG levels were significantly elevated by 0.75 and 1.0mg/kg but not 0.5mg/kg. On day 25, the latency to emerge from a dark container into a highly illuminated novel open field was measured as an indicator of anxiety. All three CPF treatment groups spent significantly less time in the dark container prior to emerging as compared to the control group, suggesting a decreased level of anxiety. This demonstrates that repeated preweanling exposure to dosages of CPF that do not inhibit brain ChE can induce a decline in the level of anxiety that is detectable during the early postweanling period.
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Naksen W, Prapamontol T, Mangklabruks A, Chantara S, Thavornyutikarn P, Srinual N, Panuwet P, Ryan PB, Riederer AM, Barr DB. Associations of maternal organophosphate pesticide exposure and PON1 activity with birth outcomes in SAWASDEE birth cohort, Thailand. ENVIRONMENTAL RESEARCH 2015; 142:288-96. [PMID: 26186137 PMCID: PMC4609250 DOI: 10.1016/j.envres.2015.06.035] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 06/25/2015] [Accepted: 06/27/2015] [Indexed: 05/21/2023]
Abstract
Prenatal organophosphate (OP) pesticide exposure has been reported to be associated with adverse birth outcomes and neurodevelopment. However, the mechanisms of toxicity of OP pesticides on human fetal development have not yet been elucidated. Our pilot study birth cohort, the Study of Asian Women and Offspring's Development and Environmental Exposures (SAWASDEE cohort) aimed to evaluate environmental chemical exposures and their relation to birth outcomes and infant neurodevelopment in 52 pregnant farmworkers in Fang district, Chiang Mai province, Thailand. A large array of data was collected multiple times during pregnancy including approximately monthly urine samples for evaluation of pesticide exposure, three blood samples for pesticide-related enzyme measurements and questionnaire data. This study investigated the changes in maternal acetylcholinesterase (AChE) and paraoxonase 1 (PON1) activities and their relation to urinary diakylphosphates (DAPs), class-related metabolites of OP pesticides, during pregnancy. Maternal AChE, butyrylcholinesterase (BChE) and PON1 activities were measured three times during pregnancy and urinary DAP concentrations were measured, on average, 8 times from enrollment during pregnancy until delivery. Among the individuals in the group with low maternal PON1 activity (n=23), newborn head circumference was negatively correlated with log10 maternal ∑DEAP and ∑DAP at enrollment (gestational age=12±3 weeks; β=-1.0 cm, p=0.03 and β=-1.8 cm, p<0.01, respectively) and at 32 weeks pregnancy (β=-1.1cm, p=0.04 and β=-2.6 cm, p=0.01, respectively). Furthermore, among these mothers, newborn birthweight was also negatively associated with log10 maternal ∑DEAP and ∑DAP at enrollment (β=-219.7 g, p=0.05 and β=-371.3g, p=0.02, respectively). Associations between maternal DAP levels and newborn outcomes were not observed in the group of participants with high maternal PON1 activity. Our results support previous findings from US birth cohort studies. This is the first study to report the associations between prenatal OP pesticide exposure and birth outcomes in Thailand.
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Affiliation(s)
- Warangkana Naksen
- Environment and Health Research Unit, Research Institute for Health Sciences, Chiang Mai University, 110 Intawaroros Road, Sriphum subdistrict, Muang district, Chiang Mai 50200, Thailand; Environmental Science Program, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Tippawan Prapamontol
- Environment and Health Research Unit, Research Institute for Health Sciences, Chiang Mai University, 110 Intawaroros Road, Sriphum subdistrict, Muang district, Chiang Mai 50200, Thailand.
| | - Ampica Mangklabruks
- Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Somporn Chantara
- Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Prasak Thavornyutikarn
- Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Niphan Srinual
- Environment and Health Research Unit, Research Institute for Health Sciences, Chiang Mai University, 110 Intawaroros Road, Sriphum subdistrict, Muang district, Chiang Mai 50200, Thailand
| | - Parinya Panuwet
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - P Barry Ryan
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Anne M Riederer
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Dana Boyd Barr
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
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Developmental exposure to organophosphate flame retardants causes behavioral effects in larval and adult zebrafish. Neurotoxicol Teratol 2015; 52:220-7. [PMID: 26344674 DOI: 10.1016/j.ntt.2015.08.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 08/31/2015] [Accepted: 08/31/2015] [Indexed: 11/24/2022]
Abstract
BACKGROUND Organophosphate flame retardants (OPFRs) have grown in usage since concerns about the health effects of the previously used polybrominated flame retardants led to their being phased out. The potential for OPFRs to cause adverse health effects of their own is still unexamined. Because of their structural similarities to organophosphate pesticides, which have themselves been heavily researched and shown to be neurobehavioral teratogens, we investigated the possibility that developmental exposure to two OPFRs, triphenyl phosphate (TPHP), and tris(1,3-dichloroisopropyl)phosphate (TDCIPP) might lead to behavioral impairment across the lifespan, as has been observed with the organophosphate pesticide chlorpyrifos. METHODS Zebrafish were exposed to 0.03 or 0.3 μM of TPHP, TDCIPP, or chlorpyrifos from 0 to 5 days post fertilization. Vehicle control consisted of 0.03% solution of DMSO. At 6 days post fertilization, larvae were tested on a locomotor assay. Separate cohorts of 6 day old larvae that were not tested on the larval assay were allowed to grow to adulthood. At 12 weeks post fertilization, these adult zebrafish were tested on a battery of behavioral assays that included tests of novel environment exploration, startle habituation, social affiliation, and predator escape. RESULTS Developmental exposure altered zebrafish behavior across the lifespan. Larval zebrafish exposed to the 0.03 μM doses of chlorpyrifos or TDCIPP exhibited significant (p<0.05) hyperactivity in the locomotor assay. Organophosphate exposure significantly (p<0.05) altered the time course of adult zebrafish behavior in the novel environment, startle habituation, and social affiliation assays. Predator escape behavior was significantly (p<0.05) reduced in fish exposed to the 0.3 μM dose of TDCIPP. Exposure also caused hyperactivity in adult fish, with fish exposed to the 0.3 μM dose of TDCIPP exhibiting significantly (p<0.05) elevated locomotor behavior in the novel environment assay. DISCUSSION Early developmental exposure to OPFRs produced behavioral impairment that persisted into adulthood. These findings support broader research investigating the role of organophosphate compounds, including the OPFRs used here, in developmental neurotoxicity.
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Peng HF, Bao XD, Zhang Y, Huang L, Huang HQ. Identification of differentially expressed proteins of brain tissue in response to methamidophos in flounder (Paralichthys olivaceus). FISH & SHELLFISH IMMUNOLOGY 2015; 44:555-565. [PMID: 25827626 DOI: 10.1016/j.fsi.2015.03.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 03/19/2015] [Accepted: 03/19/2015] [Indexed: 06/04/2023]
Abstract
Methamidophos (MAP), an organophosphorus pesticide used around the world, has been associated with a wide spectrum of toxic effects on organisms in the environment. In this study, the flounder Paralichthys olivaceus was subjected to 10 mg/L MAP for 72 h and 144 h, and the morphological and proteomic changes in the brain were observed, analyzed and compared with those in the non-exposed control group. Under the light microscope and transmission electron microscope, MAP had evidently induced changes in or damage to the flounder tissues. Gas chromatography analysis demonstrated that the MAP residues were significantly accumulated in the flounder brain tissues. Proteomic changes in the brain tissue were revealed using two-dimensional gel electrophoresis and 27 protein spots were observed to be significantly changed by MAP exposure. The results indicated that the regulated proteins were involved in immune and stress responses, protein biosynthesis and modification, signal transduction, organismal development, and 50% of them are protease. qRT-PCR was used to further detect the corresponding change of transcription. These data may be beneficial to understand the molecular mechanism of MAP toxicity in flounder, be very useful for MAP-resistance screening in flounder culture. According to our results and analyzing, heat shock protein 90 (HSP90) and granzyme K (GzmK) had taken important part in immune response to MAP-stress and could be biomarkers for MAP-stress in flounder.
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Affiliation(s)
- Hui-Fang Peng
- State Key Laboratory of Stress Cell Biology, School of Life Science, Xiamen University, Xiamen 361102, China
| | - Xiao-Dong Bao
- State Key Laboratory of Stress Cell Biology, School of Life Science, Xiamen University, Xiamen 361102, China
| | - Yong Zhang
- Department of Chemistry, College of Chemistry & Chemical Engineering, and the Key Laboratory of Chemical Biology of Fujian Province, Xiamen University, Xiamen 361102, China
| | - Lin Huang
- Department of Chemistry, Oregon State University, Corvallis, OR 97331-4003, USA
| | - He-Qing Huang
- State Key Laboratory of Stress Cell Biology, School of Life Science, Xiamen University, Xiamen 361102, China; State Key Laboratory of Marine Environmental Science, School of Ocean and Earth Science, Xiamen University, Xiamen 361102, China; Department of Chemistry, College of Chemistry & Chemical Engineering, and the Key Laboratory of Chemical Biology of Fujian Province, Xiamen University, Xiamen 361102, China.
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Gulf War agent exposure causes impairment of long-term memory formation and neuropathological changes in a mouse model of Gulf War Illness. PLoS One 2015; 10:e0119579. [PMID: 25785457 PMCID: PMC4364893 DOI: 10.1371/journal.pone.0119579] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 01/28/2015] [Indexed: 01/14/2023] Open
Abstract
Gulf War Illness (GWI) is a chronic multisymptom illness with a central nervous system component such as memory deficits, neurological, and musculoskeletal problems. There are ample data that demonstrate that exposure to Gulf War (GW) agents, such as pyridostigmine bromide (PB) and pesticides such as permethrin (PER), were key contributors to the etiology of GWI post deployment to the Persian GW. In the current study, we examined the consequences of acute (10 days) exposure to PB and PER in C57BL6 mice. Learning and memory tests were performed at 18 days and at 5 months post-exposure. We investigated the relationship between the cognitive phenotype and neuropathological changes at short and long-term time points post-exposure. No cognitive deficits were observed at the short-term time point, and only minor neuropathological changes were detected. However, cognitive deficits emerged at the later time point and were associated with increased astrogliosis and reduction of synaptophysin staining in the hippocampi and cerebral cortices of exposed mice, 5 months post exposure. In summary, our findings in this mouse model of GW agent exposure are consistent with some GWI symptom manifestations, including delayed onset of symptoms and CNS disturbances observed in GWI veterans.
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Assessment of attention and inhibitory control in rodent developmental neurotoxicity studies. Neurotoxicol Teratol 2014; 52:78-87. [PMID: 25224214 DOI: 10.1016/j.ntt.2014.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 08/16/2014] [Accepted: 09/05/2014] [Indexed: 11/20/2022]
Abstract
In designing screens to assess potential neurotoxicants, the paramount goal is that the selected assessment tools detect dysfunction if it exists. This goal is particularly challenging in the case of cognitive assessments. Cognition is not a unitary phenomenon, and indeed there is growing evidence that different aspects of cognitive functioning are subserved by distinct neural systems. As a result, if a particular neurotoxicant selectively damages certain neural systems but not others, it can impair some cognitive, sensory, or affective functions, but leave many others intact. Accordingly, studies with human subjects use batteries of cognitive tests, cognizant of the fact that no one test is capable of detecting all forms of cognitive dysfunction. In contrast, assessment of cognitive functioning in non-human animal developmental neurotoxicity (DNT) studies typically consists of a single, presumably representative, "learning and memory" task that is expected to detect all potential effects on cognitive functioning. Streamlining the cognitive assessment in these studies saves time and money, but these shortcuts can have serious consequences if the aspect of cognitive functioning that is impaired is not tapped by the single selected task. In particular, executive functioning - a constellation of cognitive functions which enables the organism to focus on multiple streams of information simultaneously, and revise plans as necessary - is poorly assessed in most animal DNT studies. The failure to adequately assess these functions - which include attention, working memory, inhibitory control, and planning - is particularly worrisome in light of evidence that the neural systems that subserve these functions may be uniquely vulnerable to early developmental insults. We illustrate the importance of tapping these areas of functioning in DNT studies by describing the pattern of effects produced by early developmental Pb exposure. Rats exposed to lead (Pb) early in development were tested on a series of automated attention tasks, as well as on a radial arm maze task. The lead-exposed rats were not impaired in this demanding radial arm maze task, despite conditions which tapped the limits of both working and long-term memory. In contrast, the automated tests designed to assess rodent executive functioning revealed selective and functionally important deficits in attention and regulation of emotion or negative affect (produced by committing an error or not receiving an expected reward). This example underscores the importance of including tasks to specifically tap executive functioning in DNT batteries. Such tasks are not only sensitive but can also shed light on the specific nature of the dysfunction, and they can implicate dysfunction of specific neural systems, information which can be used to design therapeutic interventions. Although the use of such tasks increases the time and effort needed to complete the battery, the benefits outweigh the cost, in light of the greater sensitivity of the battery and the more complete characterization of effects.
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Krawczyk N, Meyer A, Fonseca M, Lima J. Suicide mortality among agricultural workers in a region with intensive tobacco farming and use of pesticides in Brazil. J Occup Environ Med 2014; 56:993-1000. [PMID: 25046321 PMCID: PMC5240450 DOI: 10.1097/jom.0000000000000214] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVE To investigate whether suicide risk among agricultural workers is higher in regions with heavier pesticide use and/or presence of tobacco farming. METHODS Suicide mortality data were gathered from residents of the Brazilian state of Alagoas. Agricultural census data were used to arrange and classify Alagoas cities into distribution groups on the basis of variables concerning pesticide use and/or tobacco farming. Mortality odds ratio calculations were then used to compare suicide risk among agricultural and nonagricultural workers in different groups. RESULTS Suicide risk was higher among agricultural workers than among nonagricultural workers, elevated in regions that used more pesticides, and greatest in regions that produced more tobacco. CONCLUSIONS This is one of the first studies of its kind to suggest that combined effects of pesticide and tobacco exposure may be linked to higher suicide risk among agricultural workers.
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Affiliation(s)
- Noa Krawczyk
- From the Department of Preventative Medicine (Ms Krawczyk and Ms Fonseca), Icahn School of Medicine at Mount Sinai, New York, NY; Institute for Studies in Collective Health (Dr Meyer), Universidade Federal do Rio de Janeiro; and Department of Biochemistry (Dr Lima), Universidade Federal do Estado do Rio de Janeiro, RJ, Brazil
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Abstract
PURPOSE OF REVIEW The prevalence of childhood neurodevelopmental disorders has been increasing over the last several decades. Prenatal and early childhood exposure to environmental toxicants is increasingly recognized as contributing to the growing rate of neurodevelopmental disorders. Very little information is known about the mechanistic processes by which environmental chemicals alter brain development. We review the recent advances in brain imaging modalities and discuss their application in epidemiologic studies of prenatal and early childhood exposure to environmental toxicants. RECENT FINDINGS Neuroimaging techniques (volumetric and functional MRI, diffusor tensor imaging, and magnetic resonance spectroscopy) have opened unprecedented access to study the developing human brain. These techniques are noninvasive and free of ionization radiation making them suitable for research applications in children. Using these techniques, we now understand much about structural and functional patterns in the typically developing brain. This knowledge allows us to investigate how prenatal exposure to environmental toxicants may alter the typical developmental trajectory. SUMMARY MRI is a powerful tool that allows in-vivo visualization of brain structure and function. Used in epidemiologic studies of environmental exposure, it offers the promise to causally link exposure with behavioral and cognitive manifestations and ultimately to inform programs to reduce exposure and mitigate adverse effects of exposure.
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Prenatal exposure to organophosphate pesticides and neurobehavioral development of neonates: a birth cohort study in Shenyang, China. PLoS One 2014; 9:e88491. [PMID: 24551109 PMCID: PMC3923780 DOI: 10.1371/journal.pone.0088491] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 01/07/2014] [Indexed: 11/24/2022] Open
Abstract
Background A large amount of organophosphate pesticides (OPs) are used in agriculture in China every year, contributing to exposure of OPs through dietary consumption among the general population. However, the level of exposure to OPs in China is still uncertain. Objective To investigate the effect of the exposure to OPs on the neonatal neurodevelopment during pregnancy in Shenyang, China. Methods 249 pregnant women enrolled in the Central Hospital Affiliated to Shenyang Medical College from February 2011 to August 2012. A cohort of the mothers and their neonates participated in the study and information on each subject was obtained by questionnaire. Dialkyl phosphate (DAP) metabolites were detected in the urine of mothers during pregnancy to evaluate the exposure level to OPs. Neonate neurobehavioral developmental levels were assessed according to the standards of the Neonatal Behavioral Neurological Assessment (NBNA). Multiple linear regressions were utilized to analyze the association between pregnancy exposure to OPs and neonatal neurobehavioral development. Results The geometric means (GM) of urinary metabolites for dimethyl phosphate (DMP), dimethyl thiophosphate (DMTP), diethyl phosphate (DEP), and diethyl thiophosphate (DETP) in pregnant women were 18.03, 8.53, 7.14, and 5.64 µg/L, respectively. Results from multiple linear regressions showed that prenatal OP exposure was one of the most important factors affecting NBNA scores. Prenatal total DAP concentrations were inversely associated with scores on the NBNA scales.?Additionally, a 10-fold increase in DAP concentrations was associated with a decrease of 1.78 regarding the Summary NBNA (95% CI, −2.12 to −1.45). And there was an estimated 2.11-point difference in summary NBNA scores between neonates in the highest quintile of prenatal OP exposure and the lowest quintile group. Conclusion The high exposure of pregnant women to OPs in Shenyang, China was the predominant risk factor for neonatal neurobehavioral development.
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Carr RL, Graves CA, Mangum LC, Nail CA, Ross MK. Low level chlorpyrifos exposure increases anandamide accumulation in juvenile rat brain in the absence of brain cholinesterase inhibition. Neurotoxicology 2013; 43:82-89. [PMID: 24373905 DOI: 10.1016/j.neuro.2013.12.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 12/18/2013] [Accepted: 12/19/2013] [Indexed: 12/15/2022]
Abstract
The prevailing dogma is that chlorpyrifos (CPF) mediates its toxicity through inhibition of cholinesterase (ChE). However, in recent years, the toxicological effects of developmental CPF exposure have been attributed to an unknown non-cholinergic mechanism of action. We hypothesize that the endocannabinoid system may be an important target because of its vital role in nervous system development. We have previously reported that repeated exposure to CPF results in greater inhibition of fatty acid amide hydrolase (FAAH), the enzyme that metabolizes the endocannabinoid anandamide (AEA), than inhibition of either forebrain ChE or monoacylglycerol lipase (MAGL), the enzyme that metabolizes the endocannabinoid 2-arachidonylglycerol (2-AG). This exposure resulted in the accumulation of 2-AG and AEA in the forebrain of juvenile rats; however, even at the lowest dosage level used (1.0mg/kg), forebrain ChE inhibition was still present. Thus, it is not clear if FAAH activity would be inhibited at dosage levels that do not inhibit ChE. To determine this, 10 day old rat pups were exposed daily for 7 days to either corn oil or 0.5mg/kg CPF by oral gavage. At 4 and 12h post-exposure on the last day of administration, the activities of serum ChE and carboxylesterase (CES) and forebrain ChE, MAGL, and FAAH were determined as well as the forebrain AEA and 2-AG levels. Significant inhibition of serum ChE and CES was present at both 4 and 12h. There was no significant inhibition of the activities of forebrain ChE or MAGL and no significant change in the amount of 2-AG at either time point. On the other hand, while no statistically significant effects were observed at 4h, FAAH activity was significantly inhibited at 12h resulting in a significant accumulation of AEA. Although it is not clear if this level of accumulation impacts brain maturation, this study demonstrates that developmental CPF exposure at a level that does not inhibit brain ChE can alter components of endocannabinoid signaling.
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Affiliation(s)
- Russell L Carr
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
| | - Casey A Graves
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA
| | - Lee C Mangum
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA
| | - Carole A Nail
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA
| | - Matthew K Ross
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA
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Sankhwar ML, Yadav RS, Shukla RK, Singh D, Ansari RW, Pant AB, Parmar D, Khanna VK. Monocrotophos induced oxidative stress and alterations in brain dopamine and serotonin receptors in young rats. Toxicol Ind Health 2013; 32:422-36. [DOI: 10.1177/0748233713500834] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Human exposure to monocrotophos, an organophosphate pesticide, could occur due to its high use in agriculture to protect crops. Recently, we found that postlactational exposure to monocrotophos impaired cholinergic mechanisms in young rats and such changes persisted even after withdrawal of monocrotophos exposure. In continuation to this, the effect of monocrotophos on noncholinergic targets and role of oxidative stress in its neurotoxicity has been studied. Exposure of rats from postnatal day (PD)22 to PD49 to monocrotophos (0.50 or 1.0 mg kg−1 body weight, perorally) significantly impaired motor activity and motor coordination on PD50 as compared to controls. A significant decrease in the binding of 3H-spiperone to striatal membrane (26%, p < 0.01; 30%, p < 0.05) in rats exposed to monocrotophos at both the doses and increase in the binding of 3H-ketanserin to frontocortical membrane (14%, p > 0.05; 37%, p < 0.05) in those exposed at a higher dose, respectively, was observed on PD50 compared with the controls. Alterations in the binding persisted even after withdrawal of monocrotophos exposure on PD65. Increased oxidative stress in brain regions following exposure of rats to monocrotophos was also observed on PD50 that persisted 15 days after withdrawal of exposure on PD65. The results suggest that monocrotophos exerts its neurobehavioral toxicity by affecting noncholinergic functions involving dopaminergic and serotonergic systems associated with enhanced oxidative stress. The results also exhibit vulnerability of developing brain to monocrotophos as most of the changes persisted even after withdrawal of its exposure.
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Affiliation(s)
- Madhu L Sankhwar
- Council of Scientific and Industrial Research, Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India
| | - Rajesh S Yadav
- Department of Criminology and Forensic Science, School of Applied Sciences, Dr. Hari Singh Gour Central University, Sagar, Madhya Pradesh, India
| | - Rajendra K Shukla
- Council of Scientific and Industrial Research, Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India
| | - Dhirendra Singh
- Council of Scientific and Industrial Research, Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India
| | - Reyaz W Ansari
- Council of Scientific and Industrial Research, Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India
| | - Aditya B Pant
- Council of Scientific and Industrial Research, Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India
| | - Devendra Parmar
- Council of Scientific and Industrial Research, Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India
| | - Vinay K Khanna
- Council of Scientific and Industrial Research, Indian Institute of Toxicology Research, Lucknow, Uttar Pradesh, India
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35
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Ahmed MAE, Ahmed HI, El-Morsy EM. Melatonin protects against diazinon-induced neurobehavioral changes in rats. Neurochem Res 2013; 38:2227-36. [PMID: 23979727 DOI: 10.1007/s11064-013-1134-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 08/08/2013] [Accepted: 08/14/2013] [Indexed: 12/29/2022]
Abstract
Diazinon is an organophosphorous pesticide with a prominent toxicity on many body organs. Multiple mechanisms contribute to diazinon-induced deleterious effects. Inhibition of acetyl-cholinesterase, cholinergic hyperstimulation, and formation of reactive oxygen species may play a role. On the other hand, melatonin is a pineal hormone with a well-known potent antioxidant activity and a remarkable modulatory effect on many behavioral processes. The present study revealed that oral diazinon administration (25 mg/kg) increased anxiety behavior in rats subjected to elevated plus maze and open-field tests possibly via the induction of changes in brain monoamines levels (dopamine, norepinephrine, and serotonin). Additionally, brain lipid peroxides measured as malondialdehyde (MDA) and tumor necrosis factor alpha (TNF-α) levels were elevated, while the activity of brain glutathione peroxidase enzyme was reduced by diazinon. Co-administration of oral melatonin (10 mg/kg) significantly attenuated the anxiogenic activity of diazinon, rebalanced brain monoamines levels, decreased brain MDA and TNF-α levels, and increased the activity of brain glutathione peroxidase enzyme.
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Affiliation(s)
- Maha A E Ahmed
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Misr University for Science and Technology (MUST), 6th of October City, Egypt,
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36
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Acetylcholinesterase as a biomarker in environmental and occupational medicine: new insights and future perspectives. BIOMED RESEARCH INTERNATIONAL 2013; 2013:321213. [PMID: 23936791 PMCID: PMC3727120 DOI: 10.1155/2013/321213] [Citation(s) in RCA: 212] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Accepted: 06/20/2013] [Indexed: 01/23/2023]
Abstract
Acetylcholinesterase (AChE) is a key enzyme in the nervous system. It terminates nerve impulses by catalysing the hydrolysis of neurotransmitter acetylcholine. As a specific molecular target of organophosphate and carbamate pesticides, acetylcholinesterase activity and its inhibition has been early recognized to be a human biological marker of pesticide poisoning. Measurement of AChE inhibition has been increasingly used in the last two decades as a biomarker of effect on nervous system following exposure to organophosphate and carbamate pesticides in occupational and environmental medicine. The success of this biomarker arises from the fact that it meets a number of characteristics necessary for the successful application of a biological response as biomarker in human biomonitoring: the response is easy to measure, it shows a dose-dependent behavior to pollutant exposure, it is sensitive, and it exhibits a link to health adverse effects. The aim of this work is to review and discuss the recent findings about acetylcholinesterase, including its sensitivity to other pollutants and the expression of different splice variants. These insights open new perspective for the future use of this biomarker in environmental and occupational human health monitoring.
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37
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Pesticides, depression and suicide: A systematic review of the epidemiological evidence. Int J Hyg Environ Health 2013; 216:445-60. [DOI: 10.1016/j.ijheh.2012.12.003] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 12/13/2012] [Accepted: 12/18/2012] [Indexed: 11/22/2022]
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38
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Allen EMG, Florang VR, Davenport LL, Jinsmaa Y, Doorn JA. Cellular localization of dieldrin and structure-activity relationship of dieldrin analogues in dopaminergic cells. Chem Res Toxicol 2013; 26:1043-54. [PMID: 23763672 DOI: 10.1021/tx300458b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The incidence of Parkinson's disease (PD) correlates with environmental exposure to pesticides, such as the organochlorine insecticide, dieldrin. Previous studies found an increased concentration of the pesticide in the striatal region of the brains of PD patients and also that dieldrin adversely affects cellular processes associated with PD. These processes include mitochondrial function and reactive oxygen species production. However, the mechanism and specific cellular targets responsible for dieldrin-mediated cellular dysfunction and the structural components of dieldrin contributing to its toxicity (toxicophore) have not been fully defined. In order to identify the toxicophore of dieldrin, a structure-activity approach was used, with the toxicity profiles of numerous analogues of dieldrin (including aldrin, endrin, and cis-aldrin diol) assessed in PC6-3 cells. The MTT and lactate dehydrogenase (LDH) assays were used to monitor cell viability and membrane permeability after treatment with each compound. Cellular assays monitoring ROS production and extracellular dopamine metabolite levels were also used. Structure and stereochemistry for dieldrin were found to be very important for toxicity and other end points measured. Small changes in structure for dieldrin (e.g., comparison to the stereoisomer endrin) yielded significant differences in toxicity. Interestingly, the cis-diol metabolite of dieldrin was found to be significantly more toxic than the parent compound. Disruption of dopamine catabolism yielded elevated levels of the neurotoxin, 3,4-dihydroxyphenylacetaldehyde, for many organochlorines. Comparisons of the toxicity profiles for each dieldrin analogue indicated a structure-specific effect important for elucidating the mechanisms of dieldrin neurotoxicity.
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Affiliation(s)
- Erin M G Allen
- Division of Medicinal and Natural Products Chemistry, College of Pharmacy, The University of Iowa , Iowa City, Iowa 52242, United States
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Carr RL, Adams AL, Kepler DR, Ward AB, Ross MK. Induction of endocannabinoid levels in juvenile rat brain following developmental chlorpyrifos exposure. Toxicol Sci 2013; 135:193-201. [PMID: 23761300 DOI: 10.1093/toxsci/kft126] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The endogenous cannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (AEA) play vital roles during nervous system development. The degradation of 2-AG and AEA is mediated by monoacylglycerol lipase (MAGL) and fatty acid amide hydrolase (FAAH), respectively. These enzymes are inhibited following developmental chlorpyrifos (CPF) exposure. To investigate whether this inhibition is persistent or whether accumulation of endocannabinoids in the brain occurs, 10-day-old rat pups were orally exposed daily for 7 days to either corn oil or increasing dosages of CPF (1, 2.5, or 5mg/kg), and forebrains were collected at 4, 12, 24, and 48h following the last administration. All dosages inhibited cholinesterase (ChE), FAAH, and MAGL, and elevated AEA and 2-AG levels with the greatest effect occurring at 12h with ChE, FAAH, AEA, and 2-AG and at 4h with MAGL. With the high dosage, return to control levels occurred with 2-AG (48h) only. With the medium dosage, return to control levels occurred with MAGL, 2-AG, and AEA (48h) but not with ChE or FAAH. With the low dosage, return to control levels occurred with MAGL (12h), ChE and 2-AG (24h), and AEA (48h) but not with FAAH. With the lowest dosage, peak inhibition of FAAH (52%) is greater than that of ChE (24%) and that level of FAAH inhibition is sufficient to induce a persistent pattern of elevated AEA. It is possible that this pattern of elevation could alter the appropriate development of neuronal brain circuits.
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Affiliation(s)
- Russell L Carr
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi 39762-6100, USA.
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Lima CS, Dutra-Tavares AC, Nunes F, Nunes-Freitas AL, Ribeiro-Carvalho A, Filgueiras CC, Manhães AC, Meyer A, Abreu-Villaça Y. Methamidophos exposure during the early postnatal period of mice: immediate and late-emergent effects on the cholinergic and serotonergic systems and behavior. Toxicol Sci 2013; 134:125-39. [PMID: 23596261 DOI: 10.1093/toxsci/kft095] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Organophosphates (OPs) are among the most used pesticides. Although some OPs have had their use progressively more restricted, other OPs are being used without sufficient investigation of their effects. Here, we investigated the immediate neurochemical and delayed neurochemical and behavioral actions of the OP methamidophos to verify whether there are concerns regarding exposure during early postnatal development. From the third to the nineth postnatal day (PN), Swiss mice were sc injected with methamidophos (1mg/kg). At PN10, we assessed cholinergic and serotonergic biomarkers in the cerebral cortex and brainstem. From PN60 to PN63, mice were submitted to a battery of behavioral tests and subsequently to biochemical analyses. At PN10, the effects were restricted to females and to the cholinergic system: Methamidophos promoted increased choline transporter binding in the brainstem. At PN63, in the brainstem, there was a decrease in choline transporter, a female-only decrease in 5HT1A and a male-only increase in 5HT2 receptor binding. In the cortex, choline acetyltransferase activity was decreased and 5HT2 receptor binding was increased both in males and females. Methamidophos elicited behavioral alterations, suggestive of increased depressive-like behavior and impaired decision making. There were no significant alterations on anxiety-related measures and on memory/learning. Methamidophos elicited cholinergic and serotonergic alterations that depended on brain region, sex, and age of the animals. These outcomes, together with the behavioral effects, indicate that this OP is deleterious to the developing brain and that alterations are indeed identified long after the end of exposure.
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Affiliation(s)
- Carla S Lima
- Departamento de Ciências Fisiológicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
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41
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Mullins RJ, Xu S, Pereira EFR, Mamczarz J, Albuquerque EX, Gullapalli RP. Delayed hippocampal effects from a single exposure of prepubertal guinea pigs to sub-lethal dose of chlorpyrifos: a magnetic resonance imaging and spectroscopy study. Neurotoxicology 2013; 36:42-8. [PMID: 23411083 DOI: 10.1016/j.neuro.2013.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 01/29/2013] [Accepted: 02/03/2013] [Indexed: 01/09/2023]
Abstract
This study was designed to test the hypothesis that in vivo magnetic resonance imaging (MRI) and spectroscopy (MRS) can detect in adulthood the neurotoxic effects of a single exposure of prepubertal guinea pigs to the organophosphorus pesticide chlorpyrifos. Twelve female guinea pigs were given either a single dose of chlorpyrifos (0.6×LD50 or 300mg/kg, sc) or peanut oil (vehicle; 0.5ml/kg, sc) at 35-40 days of age. One year after the exposure, the animals were tested in the Morris water maze. Three days after the end of the behavioral testing, the metabolic and structural integrity of the brain of the animals was examined by means of MRI/MRS. In the Morris water maze, the chlorpyrifos-exposed guinea pigs showed significant memory deficit. Although no significant anatomical differences were found between the chlorpyrifos-exposed guinea pigs and the control animals by in vivo MRI, the chlorpyrifos-exposed animals showed significant decreases in hippocampal myo-inositol concentration using MRS. The present results indicate that a single sub-lethal exposure of prepubertal guinea pigs to the organophosphorus pesticide chlorpyrifos can lead to long-term memory deficits that are accompanied by significant reductions in the levels of hippocampal myo-inositol.
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Affiliation(s)
- Roger J Mullins
- Department of Diagnostic Radiology & Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
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42
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N’Go PK, Azzaoui FZ, Ahami AOT, Soro PR, Najimi M, Chigr F. Developmental effects of Malathion exposure on locomotor activity and anxiety-like behavior in Wistar rat. Health (London) 2013. [DOI: 10.4236/health.2013.53a080] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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43
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Burns CJ, McIntosh LJ, Mink PJ, Jurek AM, Li AA. Pesticide exposure and neurodevelopmental outcomes: review of the epidemiologic and animal studies. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2013; 16:127-283. [PMID: 23777200 PMCID: PMC3705499 DOI: 10.1080/10937404.2013.783383] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Assessment of whether pesticide exposure is associated with neurodevelopmental outcomes in children can best be addressed with a systematic review of both the human and animal peer-reviewed literature. This review analyzed epidemiologic studies testing the hypothesis that exposure to pesticides during pregnancy and/or early childhood is associated with neurodevelopmental outcomes in children. Studies that directly queried pesticide exposure (e.g., via questionnaire or interview) or measured pesticide or metabolite levels in biological specimens from study participants (e.g., blood, urine, etc.) or their immediate environment (e.g., personal air monitoring, home dust samples, etc.) were eligible for inclusion. Consistency, strength of association, and dose response were key elements of the framework utilized for evaluating epidemiologic studies. As a whole, the epidemiologic studies did not strongly implicate any particular pesticide as being causally related to adverse neurodevelopmental outcomes in infants and children. A few associations were unique for a health outcome and specific pesticide, and alternative hypotheses could not be ruled out. Our survey of the in vivo peer-reviewed published mammalian literature focused on effects of the specific active ingredient of pesticides on functional neurodevelopmental endpoints (i.e., behavior, neuropharmacology and neuropathology). In most cases, effects were noted at dose levels within the same order of magnitude or higher compared to the point of departure used for chronic risk assessments in the United States. Thus, although the published animal studies may have characterized potential neurodevelopmental outcomes using endpoints not required by guideline studies, the effects were generally observed at or above effect levels measured in repeated-dose toxicology studies submitted to the U.S. Environmental Protection Agency (EPA). Suggestions for improved exposure assessment in epidemiology studies and more effective and tiered approaches in animal testing are discussed.
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Affiliation(s)
| | | | - Pamela J. Mink
- Allina Health Center for Healthcare Research & Innovation, Minneapolis, Minnesota, USA
| | - Anne M. Jurek
- Allina Health Center for Healthcare Research & Innovation, Minneapolis, Minnesota, USA
| | - Abby A. Li
- Exponent, Inc., Menlo Park, California, USA
- Address correspondence to Abby A. Li, PhD, Attn: Rebecca Edwards, Exponent, Inc., Health Sciences Group, 149 Commonwealth Drive, Menlo Park, CA 94025-1133, USA. E-mail:
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44
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Park JW, Heah TP, Gouffon JS, Henry TB, Sayler GS. Global gene expression in larval zebrafish (Danio rerio) exposed to selective serotonin reuptake inhibitors (fluoxetine and sertraline) reveals unique expression profiles and potential biomarkers of exposure. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2012; 167:163-170. [PMID: 22575097 DOI: 10.1016/j.envpol.2012.03.039] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 03/21/2012] [Accepted: 03/22/2012] [Indexed: 05/31/2023]
Abstract
Larval zebrafish (Danio rerio) were exposed (96 h) to selective serotonin reuptake inhibitors (SSRIs) fluoxetine and sertraline and changes in transcriptomes analyzed by Affymetrix GeneChip Zebrafish Array were evaluated to enhance understanding of biochemical pathways and differences between these SSRIs. The number of genes differentially expressed after fluoxetine exposure was 288 at 25 μg/L and 131 at 250 μg/L; and after sertraline exposure was 33 at 25 μg/L and 52 at 250 μg/L. Same five genes were differentially regulated in both SSRIs indicating shared molecular pathways. Among these, the gene coding for FK506 binding protein 5, annotated to stress response regulation, was highly down-regulated in all treatments (results confirmed by qRT-PCR). Gene ontology analysis indicated at the gene expression level that regulation of stress response and cholinesterase activities were influenced by these SSRIs, and suggested that changes in transcription of these genes could be used as biomarkers of SSRI exposure.
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Affiliation(s)
- June-Woo Park
- Center for Environmental Biotechnology, University of Tennessee, 676 Dabney Hall, Knoxville, TN 37996, USA
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45
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Huen K, Bradman A, Harley K, Yousefi P, Barr DB, Eskenazi B, Holland N. Organophosphate pesticide levels in blood and urine of women and newborns living in an agricultural community. ENVIRONMENTAL RESEARCH 2012; 117:8-16. [PMID: 22683313 PMCID: PMC4309544 DOI: 10.1016/j.envres.2012.05.005] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Revised: 05/10/2012] [Accepted: 05/14/2012] [Indexed: 05/23/2023]
Abstract
Organophosphate pesticides are widely used and recent studies suggest associations of in utero exposures with adverse birth outcomes and neurodevelopment. Few studies have characterized organophosphate pesticides in human plasma or established how these levels correlate to urinary measurements. We measured organophosphate pesticide metabolites in maternal urine and chlorpyrifos and diazinon in maternal and cord plasma of subjects living in an agricultural area to compare levels in two different biological matrices. We also determined paraoxonase 1 (PON1) genotypes (PON1(192) and PON1(-108)) and PON1 substrate-specific activities in mothers and their newborns to examine whether PON1 may affect organophosphate pesticide measurements in blood and urine. Chlorpyrifos levels in plasma ranged from 0-1,726 ng/mL and non-zero levels were measured in 70.5% and 87.5% of maternal and cord samples, respectively. Diazinon levels were lower (0-0.5 ng/mL); non-zero levels were found in 33.3% of maternal plasma and 47.3% of cord plasma. Significant associations between organophosphate pesticide levels in blood and metabolite levels in urine were limited to models adjusting for PON1 levels. Increased maternal PON1 levels were associated with decreased odds of chlorpyrifos and diazinon detection (odds ratio(OR): 0.56 and 0.75, respectively). Blood organophosphate pesticide levels of study participants were similar in mothers and newborns and slightly higher than those reported in other populations. However, compared to their mothers, newborns have much lower quantities of the detoxifying PON1 enzyme suggesting that infants may be especially vulnerable to organophosphate pesticide exposures.
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Affiliation(s)
- Karen Huen
- Center for Environmental Research and Children's Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, University of California, Berkeley, CA, USA
| | - Asa Bradman
- Center for Environmental Research and Children's Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, University of California, Berkeley, CA, USA
| | - Kim Harley
- Center for Environmental Research and Children's Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, University of California, Berkeley, CA, USA
| | - Paul Yousefi
- Center for Environmental Research and Children's Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, University of California, Berkeley, CA, USA
| | - Dana Boyd Barr
- Department of Environmental Health, Rollins School of Public Health, Emory University, 1518 Clifton Road, NE, Claudia Nance Rollins Bldg, Room 2007, Atlanta, GA 30322, USA
| | - Brenda Eskenazi
- Center for Environmental Research and Children's Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, University of California, Berkeley, CA, USA
| | - Nina Holland
- Center for Environmental Research and Children's Health, School of Public Health, University of California, Berkeley, 1995 University Avenue Suite 265, Berkeley, CA 94720, University of California, Berkeley, CA, USA
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Abstract
Veterinary pesticides are used to treat a range of parasitic conditions in companion and farm animals. These products are based on a number of different compounds with different modes of action and different spectra of toxicity. The older agents include the synthetic pyrethroids and organophosphorus compounds, while the newer examples include, for example, representatives of the insect growth promoters, the neonicotinoids, and the oxadiazones. For many of these compounds, toxicity is associated with their pharmacological activity or mode of action. Thus the synthetic pyrethroids and the organophosphorus compounds exert neurotoxic effects. For others, toxicity may be associated with mechanisms that are independent of their mode of action. When used according to the manufacturer's instructions, these products are generally safe and efficacious. However, accidental contamination and misuse can lead to toxicity in operators and treated animals. These compounds are important in the treatment of parasitic disease in animals and their regulation and uses are based on favourable risk-benefit outcomes.
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Affiliation(s)
- K N Woodward
- TSGE, Concordia House St James Business Park, Grimbald Crag Court, Knaresborough, North Yorkshire UK.
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47
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Slotkin TA, Seidler FJ. Developmental neurotoxicity of organophosphates targets cell cycle and apoptosis, revealed by transcriptional profiles in vivo and in vitro. Neurotoxicol Teratol 2011; 34:232-41. [PMID: 22222554 DOI: 10.1016/j.ntt.2011.12.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Revised: 12/20/2011] [Accepted: 12/20/2011] [Indexed: 11/25/2022]
Abstract
Developmental organophosphate exposure reduces the numbers of neural cells, contributing to neurobehavioral deficits. We administered chlorpyrifos or diazinon to newborn rats on postnatal days 1-4, in doses straddling the threshold for barely-detectable cholinesterase inhibition, and evaluated gene expression in the cell cycle and apoptosis pathways on postnatal day 5. Both organophosphates evoked transcriptional changes in 20-25% of the genes in each category; chlorpyrifos and diazinon targeted the same genes, with similar magnitudes of change, as evidenced by high concordance. Furthermore, the same effects were obtained with doses above or below the threshold for cholinesterase inhibition, indicating a mechanism unrelated to anticholinesterase actions. We then evaluated the effects of chlorpyrifos in undifferentiated and differentiating PC12 cells and found even greater targeting of cell cycle and apoptosis genes, affecting up to 40% of all genes in the pathways. Notably, the genes affected in undifferentiated cells were not concordant with those in differentiating cells, pointing to dissimilar outcomes dependent on developmental stage. The in vitro model successfully identified 60-70% of the genes affected by chlorpyrifos in vivo, indicating that the effects are exerted directly on developing neural cells. Our results show that organophosphates target the genes regulating the cell cycle and apoptosis in the developing brain and in neuronotypic cells in culture, with the pattern of vulnerability dependent on the specific stage of development. Equally important, these effects do not reflect actions on cholinesterase and operate at exposures below the threshold for any detectable inhibition of this enzyme.
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Affiliation(s)
- Theodore A Slotkin
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA.
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48
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Lima CS, Nunes-Freitas AL, Ribeiro-Carvalho A, Filgueiras CC, Manhães AC, Meyer A, Abreu-Villaça Y. Exposure to methamidophos at adulthood adversely affects serotonergic biomarkers in the mouse brain. Neurotoxicology 2011; 32:718-24. [DOI: 10.1016/j.neuro.2011.08.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 06/02/2011] [Accepted: 08/11/2011] [Indexed: 12/29/2022]
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49
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Sudakin DL, Stone DL. Dialkyl phosphates as biomarkers of organophosphates: The current divide between epidemiology and clinical toxicology. Clin Toxicol (Phila) 2011; 49:771-81. [DOI: 10.3109/15563650.2011.624101] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Daniel L. Sudakin
- Oregon State University, Department of Environmental and Molecular Toxicology, 333 Weniger, Corvallis, US
| | - David L. Stone
- Oregon State University, Department of Environmental and Molecular Toxicology, 333 Weniger, Corvallis, US
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50
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Slotkin TA, Seidler FJ. Developmental exposure to organophosphates triggers transcriptional changes in genes associated with Parkinson's disease in vitro and in vivo. Brain Res Bull 2011; 86:340-7. [PMID: 21968025 DOI: 10.1016/j.brainresbull.2011.09.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 09/19/2011] [Accepted: 09/20/2011] [Indexed: 10/17/2022]
Abstract
Epidemiologic studies support a connection between organophosphate pesticide exposures and subsequent risk of Parkinson's disease (PD). We used differentiating, neuronotypic PC12 cells to compare organophosphates (chlorpyrifos, diazinon), an organochlorine (dieldrin) and a metal (Ni(2+)) for their effects on the transcription of PD-related genes. Both of the organophosphates elicited significant changes in gene expression but with differing patterns: chlorpyrifos evoked both up- and downregulation whereas diazinon elicited overall reductions in expression. Dieldrin was without effect but Ni(2+) produced a pattern resembling that of diazinon. We then exposed neonatal rats to chlorpyrifos or diazinon for the first 4 days after birth and examined the expression of PD-related genes in the brainstem and forebrain. Chlorpyrifos had no significant effect whereas diazinon produced significant increases and decreases in expression of the same PD genes that were targeted in vitro. Our results provide some of the first evidence for a mechanistic relationship between developmental organophosphate exposure and the genes known to confer PD risk in humans; but they also point to disparities between different organophosphates that reinforce the concept that their neurotoxic actions do not rest solely on their shared property as cholinesterase inhibitors. The parallel effects of diazinon and Ni(2+) also show how otherwise unrelated developmental neurotoxicants can nevertheless produce similar outcomes by converging on common molecular pathways, further suggesting a need to examine metals such as Ni(2+) as potential contributors to PD risk.
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Affiliation(s)
- Theodore A Slotkin
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Box 3813 DUMC, Durham, NC 27710, USA.
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