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López-Merino E, Cuartero MI, Esteban JA, Briz V. Perinatal exposure to pesticides alters synaptic plasticity signaling and induces behavioral deficits associated with neurodevelopmental disorders. Cell Biol Toxicol 2023; 39:2089-2111. [PMID: 35137321 PMCID: PMC10547633 DOI: 10.1007/s10565-022-09697-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 01/26/2022] [Indexed: 12/17/2022]
Abstract
Increasing evidence from animal and epidemiological studies indicates that perinatal exposure to pesticides cause developmental neurotoxicity and may increase the risk for psychiatric disorders such as autism and intellectual disability. However, the underlying pathogenic mechanisms remain largely elusive. This work was aimed at testing the hypothesis that developmental exposure to different classes of pesticides hijacks intracellular neuronal signaling contributing to synaptic and behavioral alterations associated with neurodevelopmental disorders (NDD). Low concentrations of organochlorine (dieldrin, endosulfan, and chlordane) and organophosphate (chlorpyrifos and its oxon metabolite) pesticides were chronically dosed ex vivo (organotypic rat hippocampal slices) or in vivo (perinatal exposure in rats), and then biochemical, electrophysiological, behavioral, and proteomic studies were performed. All the pesticides tested caused prolonged activation of MAPK/ERK pathway in a concentration-dependent manner. Additionally, some of them impaired metabotropic glutamate receptor-dependent long-term depression (mGluR-LTD). In the case of the pesticide chlordane, the effect was attributed to chronic modulation of MAPK/ERK signaling. These synaptic alterations were reproduced following developmental in vivo exposure to chlordane and chlorpyrifos-oxon, and were also associated with prototypical behavioral phenotypes of NDD, including impaired motor development, increased anxiety, and social and memory deficits. Lastly, proteomic analysis revealed that these pesticides differentially regulate the expression of proteins in the hippocampus with pivotal roles in brain development and synaptic signaling, some of which are associated with NDD. Based on these results, we propose a novel mechanism of synaptic dysfunction, involving chronic overactivation of MAPK and impaired mGluR-LTD, shared by different pesticides which may have important implications for NDD.
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Affiliation(s)
| | - María I Cuartero
- Neurovascular Pathophysiology Group, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | - José A Esteban
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain.
| | - Víctor Briz
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain.
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2
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Biosca-Brull J, Guardia-Escote L, Blanco J, Basaure P, Cabré M, Sánchez-Santed F, Domingo JL, Colomina MT. Prenatal, but not postnatal exposure to chlorpyrifos affects social behavior of mice and the excitatory-inhibitory balance in a sex-dependent manner. Food Chem Toxicol 2022; 169:113423. [PMID: 36113784 DOI: 10.1016/j.fct.2022.113423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 08/26/2022] [Indexed: 11/17/2022]
Abstract
The balance between excitatory and inhibitory neurotransmitters is essential for proper brain development. An imbalance between these two systems has been associated with neurodevelopmental disorders. On the other hand, literature also associates the massive use of pesticides with the increase of these disorders, with a particular focus on chlorpyrifos (CPF) a world-wide used organophosphate pesticide. This study was aimed at assessing social autistic-like behaviors on mice pre or postnatally exposed to CPF (0 or 1 mg/kg/day), in both sexes. In prenatal exposure, C57BL/6J pregnant mice were exposed to CPF through the diet, between gestational days (GD) 12 and 18, while a positive control group for some autistic behaviors was exposed to valproic acid (VPA) on GD 12 and 13. To assess postnatal exposure, C57BL/6J mice were orally exposed to the vehicle (corn oil) or CPF, from postnatal days (PND) 10-15. Social behavior and gene expression analysis were assessed on PND 45. Results showed social alterations only in males prenatally treated. GABA system was upregulated in CPF-treated females, whereas an increase in both systems was observed in both treated males. These findings suggest that males are more sensitive to prenatal CPF exposure, favoring the sex bias observed in ASD.
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Affiliation(s)
- Judit Biosca-Brull
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain; Universitat Rovira i Virgili, Department of Psychology and Research Center for Behavior Assessment (CRAMC), Tarragona, Spain; Universitat Rovira i Virgili, Laboratory of Toxicology and Environmental Health (TECNATOX), Reus, Spain.
| | - Laia Guardia-Escote
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain; Universitat Rovira i Virgili, Department of Psychology and Research Center for Behavior Assessment (CRAMC), Tarragona, Spain
| | - Jordi Blanco
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain; Universitat Rovira i Virgili, Laboratory of Toxicology and Environmental Health (TECNATOX), Reus, Spain; Universitat Rovira i Virgili, Department of Basic Medical Sciences, Reus, Spain
| | - Pia Basaure
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain
| | - Maria Cabré
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain; Universitat Rovira i Virgili, Department of Biochemistry and Biotechnology, Tarragona, Spain
| | - Fernando Sánchez-Santed
- Department of Psychology, Health Research Center (CEINSA), Almeria University, 04120, Almeria, Spain
| | - José L Domingo
- Universitat Rovira i Virgili, Laboratory of Toxicology and Environmental Health (TECNATOX), Reus, Spain
| | - Maria Teresa Colomina
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain; Universitat Rovira i Virgili, Department of Psychology and Research Center for Behavior Assessment (CRAMC), Tarragona, Spain; Universitat Rovira i Virgili, Laboratory of Toxicology and Environmental Health (TECNATOX), Reus, Spain.
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3
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Sette KN, Alugubelly N, Glenn LB, Guo-Ross SX, Parkes MK, Wilson JR, Seay CN, Carr RL. The mechanistic basis for the toxicity difference between juvenile rats and mice following exposure to the agricultural insecticide chlorpyrifos. Toxicology 2022; 480:153317. [PMID: 36096317 DOI: 10.1016/j.tox.2022.153317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 09/01/2022] [Accepted: 09/07/2022] [Indexed: 10/14/2022]
Abstract
At high exposure levels, organophosphorus insecticides (OPs) exert their toxicity in mammals through the inhibition of brain acetylcholinesterase (AChE) leading to the accumulation of acetylcholine in cholinergic synapses and hyperactivity of the nervous system. Currently, there is a concern that low-level exposure to OPs induces negative impacts in developing children and the chemical most linked to these issues is chlorpyrifos (CPF). Our laboratory has observed that a difference in the susceptibility to repeated exposure to CPF exists between juvenile mice and rats with respect to the inhibition of brain AChE. The basis for this difference is unknown but differences in the levels of the detoxification mechanisms could play a role. To investigate this, 10-day old rat and mice pups were exposed daily for 7 days to either corn oil or a range of dosages of CPF via oral gavage. Four hours following the last administration of CPF on day 16, brain, blood, and liver were collected. The inhibition of brain AChE activity was higher in juvenile rats as compared to juvenile mice. The levels of activity of the detoxification enzymes and the impact of CPF exposure on their activity were determined in the two species at this age. In blood and liver, the enzyme paraoxonase-1 (PON1) hydrolyzes the active metabolite of CPF (CPF-oxon), and the enzymes carboxylesterase (CES) and cholinesterase (ChE) act as alternative binding sites for CPF-oxon removing it from circulation and providing protection. Both species had similar levels of PON1 activity in the liver and serum. Mice had higher ChE activity in liver and serum than rats but, following CPF exposure, the percentage inhibition was similar between species at an equivalent dosage. Even though rats had slightly higher liver CES activity than mice, the level of inhibition following exposure was higher in rats. In serum, juvenile mice had an 8-fold higher CES activity than rats, and exposure to a CPF dosage that almost eliminated CES activity in rats only resulted in 22% inhibition in mice suggesting that the high serum CES activity in mice as compared to rats is a key component in this species difference. In addition, there was a species difference in the sensitivity of CES to inhibition by CPF-oxon with rats having a lower IC50 in both liver and serum as compared to mice. This greater enzyme sensitivity suggests that saturation of CES would occur more rapidly in juvenile rats than in mice, resulting in more CPF reaching the brain to inhibit AChE in rats.
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Affiliation(s)
- Katelyn N Sette
- 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
| | - Lauren B Glenn
- Center for Environmental Health Sciences, Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Shirley X Guo-Ross
- Center for Environmental Health Sciences, Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - M Katherine Parkes
- Center for Environmental Health Sciences, Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Juliet R Wilson
- Center for Environmental Health Sciences, Department of Comparative Biomedical Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Caitlin N Seay
- 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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Perez-Fernandez C, Morales-Navas M, Guardia-Escote L, Colomina MT, Giménez E, Sánchez Santed F. Pesticides and aging: Preweaning exposure to Chlorpyrifos induces a general hypomotricity state in late-adult rats. Neurotoxicology 2021; 86:69-77. [PMID: 34274376 DOI: 10.1016/j.neuro.2021.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 06/29/2021] [Accepted: 07/08/2021] [Indexed: 01/18/2023]
Abstract
The molecular and behavioral effects of the developmental exposure to low doses of Chlorpyrifos (CPF) have been intensively studied in young (neonates and adolescents), and adult animals. However, no study examined influences of developmental CPF exposure in older adult or geriatric rats. This is relevant as such ages are generally linked to cognitive decline and the onset of specific neurodegenerative disorders, some of them previously associated with CPF exposure in both preclinical and human studies. 1 mg/kg/mL of CPF was orally administered to both male and female Wistar rats from Postnatal day 10 to 15. Animals' spatial memory, learning, compulsivity, motricity, and anxiety were analyzed with Morris Water Maze (15-16 months of age) and the Plus-maze (at 18 months of age). Results showed that postnatal CPF exposure did not alter either spatial memory, compulsive-like behaviors, or anxiety levels in late-adult rats. However, CPF exposed rats were hyposensitive to brief disruptions (Probe stage) following the learning phase and showed a general decrease in locomotor activity in both paradigms. These data are relevant as it is the first time that developmental exposure to CPF has been studied at such a late age, observing important effects in locomotor activity that could be linked to specific pathologies previously associated with CPF effects in people. Future studies should extend these findings to other behaviors and molecular outcomes.
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Affiliation(s)
- Cristian Perez-Fernandez
- Department of Psychology and Health Research Center (CEINSA), Laboratory of Psychobiology, University of Almería CeiA3, 04120, Carretera de Sacramento s/n, La Cañada de San Urbano, Almería, Spain.
| | - Miguel Morales-Navas
- Department of Psychology and Health Research Center (CEINSA), Laboratory of Psychobiology, University of Almería CeiA3, 04120, Carretera de Sacramento s/n, La Cañada de San Urbano, Almería, Spain.
| | - Laia Guardia-Escote
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira I Virgili, Tarragona, Spain; Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira i Virgili, 43007, Carretera de Valls, s/n, Tarragona, Spain.
| | - María Teresa Colomina
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira I Virgili, Tarragona, Spain; Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira i Virgili, 43007, Carretera de Valls, s/n, Tarragona, Spain.
| | - Estela Giménez
- Department of Biology and Geology, University of Almería, Ctra. Sacramento, s/n, 04120 Almería, Spain.
| | - Fernando Sánchez Santed
- Department of Psychology and Health Research Center (CEINSA), Laboratory of Psychobiology, University of Almería CeiA3, 04120, Carretera de Sacramento s/n, La Cañada de San Urbano, Almería, Spain.
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Szafran BN, Borazjani A, Seay CN, Carr RL, Lehner R, Kaplan BLF, Ross MK. Effects of Chlorpyrifos on Serine Hydrolase Activities, Lipid Mediators, and Immune Responses in Lungs of Neonatal and Adult Mice. Chem Res Toxicol 2021; 34:1556-1571. [PMID: 33900070 DOI: 10.1021/acs.chemrestox.0c00488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chlorpyrifos (CPF) is an organophosphate (OP) pesticide that causes acute toxicity by inhibiting acetylcholinesterase (AChE) in the nervous system. However, endocannabinoid (eCB) metabolizing enzymes in brain of neonatal rats are more sensitive than AChE to inhibition by CPF, leading to increased levels of eCBs. Because eCBs are immunomodulatory molecules, we investigated the association between eCB metabolism, lipid mediators, and immune function in adult and neonatal mice exposed to CPF. We focused on lung effects because epidemiologic studies have linked pesticide exposures to respiratory diseases. CPF was hypothesized to disrupt lung eCB metabolism and alter lung immune responses to lipopolysaccharide (LPS), and these effects would be more pronounced in neonatal mice due to an immature immune system. We first assessed the biochemical effects of CPF in adult mice (≥8 weeks old) and neonatal mice after administering CPF (2.5 mg/kg, oral) or vehicle for 7 days. Tissues were harvested 4 h after the last CPF treatment and lung microsomes from both age groups demonstrated CPF-dependent inhibition of carboxylesterases (Ces), a family of xenobiotic and lipid metabolizing enzymes, whereas AChE activity was inhibited in adult lungs only. Activity-based protein profiling (ABPP)-mass spectrometry of lung microsomes identified 31 and 32 individual serine hydrolases in neonatal lung and adult lung, respectively. Of these, Ces1c/Ces1d/Ces1b isoforms were partially inactivated by CPF in neonatal lung, whereas Ces1c/Ces1b and Ces1c/BChE were partially inactivated in adult female and male lungs, respectively, suggesting age- and sex-related differences in their sensitivity to CPF. Monoacylglycerol lipase (MAGL) and fatty acid amide hydrolase (FAAH) activities in lung were unaffected by CPF. When LPS (1.25 mg/kg, i.p.) was administered following the 7-day CPF dosing period, little to no differences in lung immune responses (cytokines and immunophenotyping) were noted between the CPF and vehicle groups. However, a CPF-dependent increase in the amounts of dendritic cells and certain lipid mediators in female lung following LPS challenge was observed. Experiments in neonatal and adult Ces1d-/- mice yielded similar results as wild type mice (WT) following CPF treatment, except that CPF augmented LPS-induced Tnfa mRNA in adult Ces1d-/- mouse lungs. This effect was associated with decreased expression of Ces1c mRNA in Ces1d-/- mice versus WT mice in the setting of LPS exposure. We conclude that CPF exposure inactivates several Ces isoforms in mouse lung and, during an inflammatory response, increases certain lipid mediators in a female-dependent manner. However, it did not cause widespread altered lung immune effects in response to an LPS challenge.
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Affiliation(s)
- Brittany N Szafran
- Department of Comparative Biomedical Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi 39762, United States
| | - Abdolsamad Borazjani
- Department of Comparative Biomedical Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi 39762, United States
| | - Caitlin N Seay
- Department of Comparative Biomedical Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi 39762, United States
| | - Russell L Carr
- Department of Comparative Biomedical Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi 39762, United States
| | - Richard Lehner
- Departments of Cell Biology and Pediatrics, Group on Molecular & Cell Biology of Lipids, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Barbara L F Kaplan
- Department of Comparative Biomedical Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi 39762, United States
| | - Matthew K Ross
- Department of Comparative Biomedical Sciences, Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi 39762, United States
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Vorhees CV, Williams MT, Hawkey AB, Levin ED. Translating Neurobehavioral Toxicity Across Species From Zebrafish to Rats to Humans: Implications for Risk Assessment. FRONTIERS IN TOXICOLOGY 2021; 3:629229. [PMID: 35295117 PMCID: PMC8915800 DOI: 10.3389/ftox.2021.629229] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 01/27/2021] [Indexed: 12/12/2022] Open
Abstract
There is a spectrum of approaches to neurotoxicological science from high-throughput in vitro cell-based assays, through a variety of experimental animal models to human epidemiological and clinical studies. Each level of analysis has its own advantages and limitations. Experimental animal models give essential information for neurobehavioral toxicology, providing cause-and-effect information regarding risks of neurobehavioral dysfunction caused by toxicant exposure. Human epidemiological and clinical studies give the closest information to characterizing human risk, but without randomized treatment of subjects to different toxicant doses can only give information about association between toxicant exposure and neurobehavioral impairment. In vitro methods give much needed high throughput for many chemicals and mixtures but cannot provide information about toxicant impacts on behavioral function. Crucial to the utility of experimental animal model studies is cross-species translation. This is vital for both risk assessment and mechanistic determination. Interspecies extrapolation is important to characterize from experimental animal models to humans and between different experimental animal models. This article reviews the literature concerning extrapolation of neurobehavioral toxicology from established rat models to humans and from zebrafish a newer experimental model to rats. The functions covered include locomotor activity, emotion, and cognition and the neurotoxicants covered include pesticides, metals, drugs of abuse, flame retardants and polycyclic aromatic hydrocarbons. With more complete understanding of the strengths and limitations of interspecies translation, we can better use animal models to protect humans from neurobehavioral toxicity.
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Affiliation(s)
- Charles V. Vorhees
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
- Division of Neurology, Cincinnati Children's Research Foundation, Cincinnati, OH, United States
| | - Michael T. Williams
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
- Division of Neurology, Cincinnati Children's Research Foundation, Cincinnati, OH, United States
| | - Andrew B. Hawkey
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, United States
| | - Edward D. Levin
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, United States
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Berg EL, Ching TM, Bruun DA, Rivera JK, Careaga M, Ellegood J, Lerch JP, Wöhr M, Lein PJ, Silverman JL. Translational outcomes relevant to neurodevelopmental disorders following early life exposure of rats to chlorpyrifos. J Neurodev Disord 2020; 12:40. [PMID: 33327943 PMCID: PMC7745485 DOI: 10.1186/s11689-020-09342-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 11/13/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Neurodevelopmental disorders (NDDs), including intellectual disability, attention deficit hyperactivity disorder (ADHD), and autism spectrum disorder (ASD), are pervasive, lifelong disorders for which pharmacological interventions are not readily available. Substantial increases in the prevalence of NDDs over a relatively short period may not be attributed solely to genetic factors and/or improved diagnostic criteria. There is now a consensus that multiple genetic loci combined with environmental risk factors during critical periods of neurodevelopment influence NDD susceptibility and symptom severity. Organophosphorus (OP) pesticides have been identified as potential environmental risk factors. Epidemiological studies suggest that children exposed prenatally to the OP pesticide chlorpyrifos (CPF) have significant mental and motor delays and strong positive associations for the development of a clinical diagnosis of intellectual delay or disability, ADHD, or ASD. METHODS We tested the hypothesis that developmental CPF exposure impairs behavior relevant to NDD phenotypes (i.e., deficits in social communication and repetitive, restricted behavior). Male and female rat pups were exposed to CPF at 0.1, 0.3, or 1.0 mg/kg (s.c.) from postnatal days 1-4. RESULTS These CPF doses did not significantly inhibit acetylcholinesterase activity in the blood or brain but significantly impaired pup ultrasonic vocalizations (USV) in both sexes. Social communication in juveniles via positive affiliative 50-kHz USV playback was absent in females exposed to CPF at 0.3 mg/kg and 1.0 mg/kg. In contrast, this CPF exposure paradigm had no significant effect on gross locomotor abilities or contextual and cued fear memory. Ex vivo magnetic resonance imaging largely found no differences between the CPF-exposed rats and the corresponding vehicle controls using strict false discovery correction; however, there were interesting trends in females in the 0.3 mg/kg dose group. CONCLUSIONS This work generated and characterized a rat model of developmental CPF exposure that exhibits adverse behavioral phenotypes resulting from perinatal exposures at levels that did not significantly inhibit acetylcholinesterase activity in the brain or blood. These data suggest that current regulations regarding safe levels of CPF need to be reconsidered.
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Affiliation(s)
- Elizabeth L Berg
- MIND Institute and Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, USA
| | - Tianna M Ching
- MIND Institute and Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, USA
| | - Donald A Bruun
- MIND Institute and Department of Molecular Biosciences, University of California Davis School of Veterinary Medicine, Davis, CA, USA
| | - Josef K Rivera
- MIND Institute and Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, USA
| | - Milo Careaga
- MIND Institute and Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, USA
| | - Jacob Ellegood
- Mouse Imaging Centre, Toronto Centre for Phenogenomics, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Jason P Lerch
- Mouse Imaging Centre, Toronto Centre for Phenogenomics, The Hospital for Sick Children, Toronto, Ontario, Canada
- Wellcome Centre for Integrative Neuroimaging, The University of Oxford, Oxford, UK
| | - Markus Wöhr
- Behavioral Neuroscience, Experimental and Biological Psychology, Philipps University of Marburg, Marburg, Germany
- Laboratory for Behavioral Neuroscience, Department of Biology, Faculty of Science, University of Southern Denmark, Campusvej 55, DK-5230, Odense M, Denmark
| | - Pamela J Lein
- MIND Institute and Department of Molecular Biosciences, University of California Davis School of Veterinary Medicine, Davis, CA, USA
| | - Jill L Silverman
- MIND Institute and Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, USA.
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Gestational exposures to organophosphorus insecticides: From acute poisoning to developmental neurotoxicity. Neuropharmacology 2020; 180:108271. [PMID: 32814088 DOI: 10.1016/j.neuropharm.2020.108271] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 07/03/2020] [Accepted: 08/10/2020] [Indexed: 11/22/2022]
Abstract
For over three-quarters of a century, organophosphorus (OP) insecticides have been ubiquitously used in agricultural, residential, and commercial settings and in public health programs to mitigate insect-borne diseases. Their broad-spectrum insecticidal effectiveness is accounted for by the irreversible inhibition of acetylcholinesterase (AChE), the enzyme that catalyzes acetylcholine (ACh) hydrolysis, in the nervous system of insects. However, because AChE is evolutionarily conserved, OP insecticides are also toxic to mammals, including humans, and acute OP intoxication remains a major public health concern in countries where OP insecticide usage is poorly regulated. Environmental exposures to OP levels that are generally too low to cause marked inhibition of AChE and to trigger acute signs of intoxication, on the other hand, represent an insidious public health issue worldwide. Gestational exposures to OP insecticides are particularly concerning because of the exquisite sensitivity of the developing brain to these insecticides. The present article overviews and discusses: (i) the health effects and therapeutic management of acute OP poisoning during pregnancy, (ii) epidemiological studies examining associations between environmental OP exposures during gestation and health outcomes of offspring, (iii) preclinical evidence that OP insecticides are developmental neurotoxicants, and (iv) potential mechanisms underlying the developmental neurotoxicity of OP insecticides. Understanding how gestational exposures to different levels of OP insecticides affect pregnancy and childhood development is critical to guiding implementation of preventive measures and direct research aimed at identifying effective therapeutic interventions that can limit the negative impact of these exposures on public health.
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Perez-Fernandez C, Morales-Navas M, Guardia-Escote L, Colomina MT, Giménez E, Sánchez-Santed F. Postnatal exposure to low doses of Chlorpyrifos induces long-term effects on 5C-SRTT learning and performance, cholinergic and GABAergic systems and BDNF expression. Exp Neurol 2020; 330:113356. [DOI: 10.1016/j.expneurol.2020.113356] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 04/13/2020] [Accepted: 05/04/2020] [Indexed: 12/19/2022]
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10
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Perez-Fernandez C, Morales-Navas M, Aguilera-Sáez LM, Abreu AC, Guardia-Escote L, Fernández I, Garrido-Cárdenas JA, Colomina MT, Giménez E, Sánchez-Santed F. Medium and long-term effects of low doses of Chlorpyrifos during the postnatal, preweaning developmental stage on sociability, dominance, gut microbiota and plasma metabolites. ENVIRONMENTAL RESEARCH 2020; 184:109341. [PMID: 32179266 DOI: 10.1016/j.envres.2020.109341] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 01/30/2020] [Accepted: 03/02/2020] [Indexed: 06/10/2023]
Abstract
Autism spectrum disorder (ASD) is a complex neurodevelopmental pathology characterized by altered verbalizations, reduced social interaction behavior, and stereotypies. Environmental factors have been associated with its development. Some researchers have focused on pesticide exposure. Chlorpyrifos (CPF) is the most used Organophosphate. Previous developmental studies with CPF showed decreased, enhanced or no effect on social outcomes eminently in mice. The study of CPF exposure during preweaning stages on social behavior is sparse in mice and non-existent in rats. d stressors could be at the basis of ASD development, and around postnatal day 10 in the rat is equivalent to the human birthday in neurodevelopmental terms. We explored the effects of exposure to low doses (1mg/kg/mL/day) of CPF during this stage regarding: sociability, dominance gut microbiome and plasma metabolomic profile, since alterations in these systems have also been linked to ASD. There was a modest influence of CPF on social behavior in adulthood, with null effects during adolescence. Dominance and hierarchical status were not affected by exposure. Dominance status explained the significant reduction in reaction to social novelty observed on the sociability test. CPF induced a significant gut microbiome dysbiosis and triggered a hyperlipidemic, hypoglycemic/hypogluconeogenesis and a general altered cell energy production in females. These behavioral results in rats extend and complement previous studies with mice and show novel influences on gut metagenomics and plasma lipid profile and metabolomics, but do not stablish a relation between the exposure to CPF and the ASD phenotype. The effects of dominance status on reaction to social novelty have an important methodological meaning for future research on sociability.
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Affiliation(s)
- Cristian Perez-Fernandez
- Department of Psychology and Health Research Center, University of Almería, Ctra. Sacramento, s/n, 04120, Almería, Spain.
| | - Miguel Morales-Navas
- Department of Psychology and Health Research Center, University of Almería, Ctra. Sacramento, s/n, 04120, Almería, Spain.
| | - Luis Manuel Aguilera-Sáez
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, University of Almería, Ctra. Sacramento, s/n, 04120, Almería, Spain.
| | - Ana Cristina Abreu
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, University of Almería, Ctra. Sacramento, s/n, 04120, Almería, Spain.
| | - Laia Guardia-Escote
- Department of Biochemistry and Biotechnology and Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira i Virgili, 43007, C/ Macel.lí Domingo 1, Tarragona, Spain.
| | - Ignacio Fernández
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, University of Almería, Ctra. Sacramento, s/n, 04120, Almería, Spain.
| | | | - María Teresa Colomina
- Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira i Virgili, 43007, C/ Carretera de Valls, s/n, Tarragona, Spain.
| | - Estela Giménez
- Department of Biology and Geology, University of Almería, Ctra. Sacramento, s/n, 04120, Almería, Spain.
| | - Fernando Sánchez-Santed
- Department of Psychology and Health Research Center, University of Almería, Ctra. Sacramento, s/n, 04120, Almería, Spain.
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11
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Silva MH. Effects of low‐dose chlorpyrifos on neurobehavior and potential mechanisms: A review of studies in rodents, zebrafish, and
Caenorhabditis elegans. Birth Defects Res 2020; 112:445-479. [DOI: 10.1002/bdr2.1661] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 01/10/2020] [Accepted: 02/12/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Marilyn H. Silva
- Retired from a career in regulatory toxicology and risk assessment
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12
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Bumbăcilă B, Putz MV. Neurotoxicity of Pesticides: The Roadmap for the Cubic Mode of Action. Curr Med Chem 2020; 27:54-77. [DOI: 10.2174/0929867326666190704142354] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 05/08/2019] [Accepted: 06/20/2019] [Indexed: 01/15/2023]
Abstract
Pesticides are used today on a planetary-wide scale. The rising need for substances with this
biological activity due to an increasing consumption of agricultural and animal products and to the
development of urban areas makes the chemical industry to constantly investigate new molecules or to
improve the physicochemical characteristics, increase the biological activities and improve the toxicity
profiles of the already known ones. Molecular databases are increasingly accessible for in vitro and in
vivo bioavailability studies. In this context, structure-activity studies, by their in silico - in cerebro
methods, are used to precede in vitro and in vivo studies in plants and experimental animals because
they can indicate trends by statistical methods or biological activity models expressed as mathematical
equations or graphical correlations, so a direction of study can be developed or another can be abandoned,
saving financial resources, time and laboratory animals. Following this line of research the present paper
reviews the Structure-Activity Relationship (SAR) studies and proposes a correlation between a topological
connectivity index and the biological activity or toxicity made as a result of a study performed on 11 molecules
of organophosphate compounds, randomly chosen, with a basic structure including a Phosphorus atom
double bounded to an Oxygen atom or to a Sulfur one and having three other simple covalent bonds with two
alkoxy (-methoxy or -ethoxy) groups and to another functional group different from the alkoxy groups. The
molecules were packed on a cubic structure consisting of three adjacent cubes, respecting a principle of topological
efficiency, that of occupying a minimal space in that cubic structure, a method that was called the Clef
Method. The central topological index selected for correlation was the Wiener index, since it was possible
this way to discuss different adjacencies between the nodes in the graphs corresponding to the organophosphate
compounds molecules packed on the cubic structure; accordingly, "three dimensional" variants of these
connectivity indices could be considered and further used for studying the qualitative-quantitative relationships
for the specific molecule-enzyme interaction complexes, including correlation between the Wiener
weights (nodal specific contributions to the total Wiener index of the molecular graph) and the biochemical
reactivity of some of the atoms. Finally, when passing from SAR to Q(uantitative)-SAR studies, especially by
the present advanced method of the cubic molecule (Clef Method) and its good assessment of the
(neuro)toxicity of the studied molecules and of their inhibitory effect on the target enzyme - acetylcholinesterase,
it can be seen that a predictability of the toxicity and activity of different analogue compounds can
be ensured, facilitating the in vivo experiments or improving the usage of pesticides.
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Affiliation(s)
- Bogdan Bumbăcilă
- Laboratory of Computational and Structural Physical-Chemistry for Nanosciences and QSAR, Biology- Chemistry Department, Faculty of Chemistry, Biology, Geography at West University of Timisoara, Pestalozzi Street No.16, Timisoara RO-300115, Romania
| | - Mihai V. Putz
- Laboratory of Computational and Structural Physical-Chemistry for Nanosciences and QSAR, Biology- Chemistry Department, Faculty of Chemistry, Biology, Geography at West University of Timisoara, Pestalozzi Street No.16, Timisoara RO-300115, Romania
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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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Perez-Fernandez C, Morales-Navas M, Guardia-Escote L, Garrido-Cárdenas JA, Colomina MT, Giménez E, Sánchez-Santed F. Long-term effects of low doses of Chlorpyrifos exposure at the preweaning developmental stage: A locomotor, pharmacological, brain gene expression and gut microbiome analysis. Food Chem Toxicol 2020; 135:110865. [DOI: 10.1016/j.fct.2019.110865] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 09/05/2019] [Accepted: 09/30/2019] [Indexed: 12/26/2022]
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15
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APOE genetic background and sex confer different vulnerabilities to postnatal chlorpyrifos exposure and modulate the response to cholinergic drugs. Behav Brain Res 2019; 376:112195. [DOI: 10.1016/j.bbr.2019.112195] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 08/20/2019] [Accepted: 08/28/2019] [Indexed: 01/30/2023]
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16
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Basaure P, Guardia-Escote L, Biosca-Brull J, Blanco J, Cabré M, Peris-Sampedro F, Sánchez-Santed F, Domingo JL, Colomina MT. Exposure to chlorpyrifos at different ages triggers APOE genotype-specific responses in social behavior, body weight and hypothalamic gene expression. ENVIRONMENTAL RESEARCH 2019; 178:108684. [PMID: 31472362 DOI: 10.1016/j.envres.2019.108684] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/20/2019] [Accepted: 08/20/2019] [Indexed: 06/10/2023]
Abstract
To date, we have shown that apolipoprotein E (APOE) polymorphisms differentially modulate the neurobehavioral and metabolic effects of chlorpyrifos (CPF), a widely used pesticide, which is detected as residue in food. We previously reported that, after being exposed to CPF, APOE3 subjects exhibit metabolic dysfunctions while APOE4 subjects undergo changes in behavior. In the current study, we investigated the effects of a double exposure to CPF on social behavior and hypothalamic gene expression in apoE-targeted replacement (TR) mice. Male apoE3-and apoE4-TR mice were exposed to CPF at 0 or 1 mg/kg/day on postnatal days 10-15 and then, during adulthood (5 months of age), fed a CPF-supplemented diet (0 or 2 mg/kg/day) for 15 days. During adult exposure to CPF, body weight gain and food intake were monitored. At the end of the adult exposure period, we evaluated social behavior in a three-chamber test, as well as mRNA levels of hypothalamic neuropeptides and receptors related to social behavior and feeding control. Adult CPF exposure increased food intake in general, but only apoE4 mice increased their body weight. Postnatal CPF exposure improved preference for the social contexts in apoE4 mice while adult CPF exposure did the same in apoE3 mice. Anorexigenic-peptide and social-related behavior gene expression decreased as a result of adult CPF exposure in apoE4 mice, and neuropeptide Y was more expressed in apoE4 mice. These results indicate that CPF exposure produces orexigenic and metabolic effects and enlarges individual differences in social behavior, especially in apoE3 mice.
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Affiliation(s)
- Pia Basaure
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira i Virgili, Tarragona, Spain; Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira i Virgili, Tarragona, Spain; Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat Rovira i Virgili, Reus, Spain
| | - Laia Guardia-Escote
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira i Virgili, Tarragona, Spain; Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat Rovira i Virgili, Reus, Spain; Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, Tarragona, Spain
| | - Judit Biosca-Brull
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira i Virgili, Tarragona, Spain; Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira i Virgili, Tarragona, Spain; Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat Rovira i Virgili, Reus, Spain
| | - Jordi Blanco
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira i Virgili, Tarragona, Spain; Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat Rovira i Virgili, Reus, Spain
| | - Maria Cabré
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira i Virgili, Tarragona, Spain; Department of Biochemistry and Biotechnology, Universitat Rovira i Virgili, Tarragona, Spain
| | - Fiona Peris-Sampedro
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira i Virgili, Tarragona, Spain; Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | | | - José L Domingo
- Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat Rovira i Virgili, Reus, Spain
| | - Maria Teresa Colomina
- Research in Neurobehavior and Health (NEUROLAB), Universitat Rovira i Virgili, Tarragona, Spain; Department of Psychology and Research Center for Behavior Assessment (CRAMC), Universitat Rovira i Virgili, Tarragona, Spain; Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat Rovira i Virgili, Reus, Spain.
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17
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Guardia-Escote L, Basaure P, Blanco J, Cabré M, Pérez-Fernández C, Sánchez-Santed F, Domingo JL, Colomina MT. Postnatal exposure to chlorpyrifos produces long-term effects on spatial memory and the cholinergic system in mice in a sex- and APOE genotype-dependent manner. Food Chem Toxicol 2018; 122:1-10. [DOI: 10.1016/j.fct.2018.09.069] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 09/22/2018] [Accepted: 09/28/2018] [Indexed: 12/13/2022]
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18
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Tartaglione AM, Cipriani C, Chiarotti F, Perrone B, Balestrieri E, Matteucci C, Sinibaldi-Vallebona P, Calamandrei G, Ricceri L. Early Behavioral Alterations and Increased Expression of Endogenous Retroviruses Are Inherited Across Generations in Mice Prenatally Exposed to Valproic Acid. Mol Neurobiol 2018; 56:3736-3750. [DOI: 10.1007/s12035-018-1328-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 08/22/2018] [Indexed: 12/12/2022]
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19
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Postnatal chlorpyrifos exposure and apolipoprotein E (APOE) genotype differentially affect cholinergic expression and developmental parameters in transgenic mice. Food Chem Toxicol 2018; 118:42-52. [DOI: 10.1016/j.fct.2018.04.065] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Revised: 04/12/2018] [Accepted: 04/30/2018] [Indexed: 02/08/2023]
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20
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Comfort N, Re DB. Sex-Specific Neurotoxic Effects of Organophosphate Pesticides Across the Life Course. Curr Environ Health Rep 2018; 4:392-404. [PMID: 29063415 DOI: 10.1007/s40572-017-0171-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
PURPOSE OF REVIEW This review discusses the sex-specific effects of exposure to various organophosphate (OP) pesticides throughout the life course and potential reasons for the differential vulnerabilities observed across sexes. RECENT FINDINGS Sex is a crucial factor in the response to toxicants, yet the sex-specific effects of OP exposure, particularly in juveniles and adults, remain unresolved. This is largely due to study design and inconsistencies in exposure and outcome assessments. Exposure to OPs results in multiple adverse outcomes influenced by many factors including sex. Reported sex-specific effects suggest that males are more susceptible to OPs, which reflects the sex-dependent prevalence of various neurodevelopmental and neurodegenerative disorders such as autism and amyotrophic lateral sclerosis (ALS), in which males are at greater risk. Thus, this review proposes that the biological sex-specific effects elicited by OP exposure may in part underlie the dimorphic susceptibilities observed in neurological disorders. Understanding the immediate and long-term effects of OP exposure across sexes will be critical in advancing our understanding of OP-induced neurotoxicity and disease.
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Affiliation(s)
- Nicole Comfort
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, 10032, USA. .,NIEHS Center for Environmental Health Sciences in Northern Manhattan, Columbia University, New York, NY, 10032, USA. .,, 722 W 168th Street, 11th floor, New York, NY, 10032, USA.
| | - Diane B Re
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, 10032, USA. .,NIEHS Center for Environmental Health Sciences in Northern Manhattan, Columbia University, New York, NY, 10032, USA. .,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA. .,, 722 W 168th Street Suite 1107B, New York, NY, 10032, USA.
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21
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Furlong MA, Herring A, Buckley JP, Goldman BD, Daniels JL, Engel LS, Wolff MS, Chen J, Wetmur J, Barr DB, Engel SM. Prenatal exposure to organophosphorus pesticides and childhood neurodevelopmental phenotypes. ENVIRONMENTAL RESEARCH 2017; 158:737-747. [PMID: 28743040 PMCID: PMC5577985 DOI: 10.1016/j.envres.2017.07.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 06/15/2017] [Accepted: 07/10/2017] [Indexed: 05/07/2023]
Abstract
Prenatal exposure to organophosphorus pesticides (OPs) has been associated with different neurodevelopmental outcomes across different cohorts. A phenotypic approach may address some of these differences by incorporating information across scales and accounting for the complex correlational structure of neurodevelopmental outcomes. Additionally, Bayesian hierarchical modeling can account for confounding by collinear co-exposures. We use this framework to examine associations between prenatal exposure to OPs and behavior, executive functioning, and IQ assessed at age 6-9 years in a cohort of 404 mother/infant pairs recruited during pregnancy. We derived phenotypes of neurodevelopment with a factor analysis, and estimated associations between OP metabolites and these phenotypes in Bayesian hierarchical models for exposure mixtures. We report seven factors: 1) Impulsivity and Externalizing, 2) Executive Functioning, 3) Internalizing, 4) Perceptual Reasoning, 5) Adaptability, 6) Processing Speed, and 7) Verbal Intelligence. These, along with the Working Memory Index, were standardized and scaled so that positive values reflected positive attributes and negative values represented adverse outcomes. Standardized dimethylphosphate metabolites were negatively associated with Internalizing factor scores (β^ - 0.13, 95% CI - 0.26, 0.00) but positively associated with Executive Functioning factor scores (β^ 0.18, 95% CI 0.04, 0.31). Standardized diethylphosphate metabolites were negatively associated with the Working Memory Index (β^ - 0.17, 95% CI - 0.33, - 0.03). Associations with factor scores were generally stronger and more precise than associations with individual instrument-specific items. Factor analysis of outcomes may provide some advantages in etiological studies of childhood neurodevelopment by incorporating information across scales to reduce dimensionality and improve precision.
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Affiliation(s)
- Melissa A Furlong
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, United States.
| | - Amy Herring
- Department of Statistical Science and Global Health Institute, Duke University, United States
| | - Jessie P Buckley
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, United States
| | - Barbara D Goldman
- Department of Psychology and Neuroscience & FPG Child Development Institute, University of North Carolina at Chapel Hill, United States
| | - Julie L Daniels
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, United States
| | - Lawrence S Engel
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, United States
| | - Mary S Wolff
- Department of Environmental Medicine and Public Health, Mount Sinai School of Medicine, United States
| | - Jia Chen
- Department of Environmental Medicine and Public Health, Mount Sinai School of Medicine, United States
| | - Jim Wetmur
- Department of Genetics and Genomic Sciences, Mount Sinai School of Medicine, United States
| | - Dana Boyd Barr
- Department of Environmental Health, Rollins School of Public Health, Emory University, United States
| | - Stephanie M Engel
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, United States
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22
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Estrela FN, Rabelo LM, Vaz BG, de Oliveira Costa DR, Pereira I, de Lima Rodrigues AS, Malafaia G. Short-term social memory deficits in adult female mice exposed to tannery effluent and possible mechanism of action. CHEMOSPHERE 2017; 184:148-158. [PMID: 28586655 DOI: 10.1016/j.chemosphere.2017.05.174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 05/23/2017] [Accepted: 05/30/2017] [Indexed: 06/07/2023]
Abstract
The accumulated organic residues in tannery-plant courtyards are an eating attraction to small rodents; however, the contact of these animals with these residues may change their social behavior. Thus, the aim of the present study is to investigate whether the exposure to tannery effluent (TE) can damage the social recognition memory of female Swiss mice, as well as to assess whether vitamin C supplementation could provide information about how TE constituents can damage these animals' memory. We have observed that resident females exposed to TE (without vitamin supplementation) did not explore the anogenital region, their body or chased intruding females for shorter time or with lower frequency during the retest session of the social recognition test, fact that indicates social recognition memory deficit in these animals. Such finding is reinforced by the confirmation that there was no change in the animals' olfactory function during the buried food test, or locomotor changes in females exposed to the pollutant. Since no behavioral change was observed in the females exposed to TE and treated with vitamin C (before or after the exposure), it is possible saying that these social cognitive impairments seem to be directly related to the imbalance between the cellular production of reactive oxygen species and the counteracting antioxidant mechanisms (oxidative stress) in female mice exposed to the pollutant (without vitamin supplementation). Therefore, the present study evidences that the direct contact with tannery effluent, even for a short period-of-time, may cause short-term social memory deficits in adult female Swiss mice.
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Affiliation(s)
- Fernanda Neves Estrela
- Laboratório de Pesquisas Biológicas, Instituto Federal Goiano - Campus Urutaí, GO, Brazil
| | - Letícia Martins Rabelo
- Laboratório de Pesquisas Biológicas, Instituto Federal Goiano - Campus Urutaí, GO, Brazil
| | - Boniek Gontijo Vaz
- Programa de Pós-Graduação em Química, Universidade Federal de Goiás - Campus Samambaia, Goiânia, GO, Brazil
| | | | - Igor Pereira
- Programa de Pós-Graduação em Química, Universidade Federal de Goiás - Campus Samambaia, Goiânia, GO, Brazil
| | - Aline Sueli de Lima Rodrigues
- Departamento de Ciências Biológicas, Programa de Pós-Graduação em Conservação de Recursos Naturais do Cerrado, Instituto Federal Goiano - Campus Urutaí, GO, Brazil
| | - Guilherme Malafaia
- Laboratório de Pesquisas Biológicas, Instituto Federal Goiano - Campus Urutaí, GO, Brazil; Departamento de Ciências Biológicas, Programa de Pós-Graduação em Conservação de Recursos Naturais do Cerrado, Instituto Federal Goiano - Campus Urutaí, GO, Brazil; Programa de Pós-Graduação em Biodiversidade Animal, Universidade Federal de Goiás - Campus Samambaia, Goiânia, GO, Brazil.
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23
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Burke RD, Todd SW, Lumsden E, Mullins RJ, Mamczarz J, Fawcett WP, Gullapalli RP, Randall WR, Pereira EFR, Albuquerque EX. Developmental neurotoxicity of the organophosphorus insecticide chlorpyrifos: from clinical findings to preclinical models and potential mechanisms. J Neurochem 2017; 142 Suppl 2:162-177. [PMID: 28791702 DOI: 10.1111/jnc.14077] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 05/16/2017] [Accepted: 05/18/2017] [Indexed: 12/20/2022]
Abstract
Organophosphorus (OP) insecticides are pest-control agents heavily used worldwide. Unfortunately, they are also well known for the toxic effects that they can trigger in humans. Clinical manifestations of an acute exposure of humans to OP insecticides include a well-defined cholinergic crisis that develops as a result of the irreversible inhibition of acetylcholinesterase (AChE), the enzyme that hydrolyzes the neurotransmitter acetylcholine (ACh). Prolonged exposures to levels of OP insecticides that are insufficient to trigger signs of acute intoxication, which are hereafter referred to as subacute exposures, have also been associated with neurological deficits. In particular, epidemiological studies have reported statistically significant correlations between prenatal subacute exposures to OP insecticides, including chlorpyrifos, and neurological deficits that range from cognitive impairments to tremors in childhood. The primary objectives of this article are: (i) to address the short- and long-term neurological issues that have been associated with acute and subacute exposures of humans to OP insecticides, especially early in life (ii) to discuss the translational relevance of animal models of developmental exposure to OP insecticides, and (iii) to review mechanisms that are likely to contribute to the developmental neurotoxicity of OP insecticides. Most of the discussion will be focused on chlorpyrifos, the top-selling OP insecticide in the United States and throughout the world. These points are critical for the identification and development of safe and effective interventions to counter and/or prevent the neurotoxic effects of these chemicals in the developing brain. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms.
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Affiliation(s)
- Richard D Burke
- Division of Translational Toxicology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Spencer W Todd
- Division of Translational Toxicology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Eric Lumsden
- Division of Translational Toxicology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Roger J Mullins
- Department of Diagnostic Radiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Jacek Mamczarz
- Division of Translational Toxicology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - William P Fawcett
- Division of Translational Toxicology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Rao P Gullapalli
- Department of Diagnostic Radiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - William R Randall
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Edna F R Pereira
- Division of Translational Toxicology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Department of Pharmacology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Edson X Albuquerque
- Division of Translational Toxicology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Department of Pharmacology, University of Maryland School of Medicine, Baltimore, Maryland, USA
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Gao J, Naughton SX, Beck WD, Hernandez CM, Wu G, Wei Z, Yang X, Bartlett MG, Terry AV. Chlorpyrifos and chlorpyrifos oxon impair the transport of membrane bound organelles in rat cortical axons. Neurotoxicology 2017; 62:111-123. [PMID: 28600141 DOI: 10.1016/j.neuro.2017.06.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 06/02/2017] [Accepted: 06/02/2017] [Indexed: 01/13/2023]
Abstract
Chlorpyrifos (CPF) is an extensively used organophosphorus pesticide that has recently come under increasing scrutiny due to environmental health concerns particularly its association with neurodevelopmental defects. While the insecticidal actions and acute toxicity of CPF are attributed to its oxon metabolite (CPO) which potently inhibits the cholinergic enzyme acetylcholinesterase (AChE), there is significant evidence that CPF, CPO, and other organophosphates may affect a variety of neuronal targets and processes that are not directly related to AChE. Previously, in adult rat sciatic nerves ex vivo and postnatal neurons from rats in vitro we observed that CPF and CPO impaired the movements of vesicles and mitochondria in axons. Here, in embryonic neurons from rats in culture, we evaluated 24h exposures to CPF and CPO across picomolar to micromolar concentrations for effects on fast axonal transport of membrane bound organelles (MBOs) that contained the amyloid precursor protein (APP) tagged with the fluorescent marker, Dendra2 (APPDendra2). The most notable observations of this study were concentration-dependent decreases in the velocity and percentage of MBOs moving in the anterograde direction, an increase in the number of stationary MBOs, and an increased frequency of pauses associated with both CPF and CPO. These effects occurred at concentrations that did not significantly inhibit AChE activity, they were not blocked by cholinergic receptor antagonists, and they were not associated with compromised cell viability. These effects of CPF and CPO may be significant given the importance of axonal transport to neuronal development as well the function of fully developed neurons.
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Affiliation(s)
- Jie Gao
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia
| | - Sean X Naughton
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia
| | - Wayne D Beck
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia
| | - Caterina M Hernandez
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia
| | - Guangyu Wu
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia
| | - Zhe Wei
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia
| | - Xiangkun Yang
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, 250 W. Green Street, Athens, 30602, Georgia
| | - Michael G Bartlett
- Department of Pharmaceutical and Biomedical Sciences, The University of Georgia College of Pharmacy, 250 W. Green Street, Athens, 30602, Georgia
| | - Alvin V Terry
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, Augusta, 30912, Georgia.
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Abreu-Villaça Y, Levin ED. Developmental neurotoxicity of succeeding generations of insecticides. ENVIRONMENT INTERNATIONAL 2017; 99:55-77. [PMID: 27908457 PMCID: PMC5285268 DOI: 10.1016/j.envint.2016.11.019] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Revised: 11/17/2016] [Accepted: 11/17/2016] [Indexed: 05/19/2023]
Abstract
Insecticides are by design toxic. They must be toxic to effectively kill target species of insects. Unfortunately, they also have off-target toxic effects that can harm other species, including humans. Developmental neurotoxicity is one of the most prominent off-target toxic risks of insecticides. Over the past seven decades several classes of insecticides have been developed, each with their own mechanisms of effect and toxic side effects. This review covers the developmental neurotoxicity of the succeeding generations of insecticides including organochlorines, organophosphates, pyrethroids, carbamates and neonicotinoids. The goal of new insecticide development is to more effectively kill target species with fewer toxic side effects on non-target species. From the experience with the developmental neurotoxicity caused by the generations of insecticides developed in the past advice is offered how to proceed with future insecticide development to decrease neurotoxic risk.
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Affiliation(s)
- Yael Abreu-Villaça
- Departamento de Ciências Fisiologicas, Universidade do Estado do Rio de Janeiro (UERJ), RJ, Brazil
| | - Edward D Levin
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA.
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Mamczarz J, Pescrille JD, Gavrushenko L, Burke RD, Fawcett WP, DeTolla LJ, Chen H, Pereira EFR, Albuquerque EX. Spatial learning impairment in prepubertal guinea pigs prenatally exposed to the organophosphorus pesticide chlorpyrifos: Toxicological implications. Neurotoxicology 2016; 56:17-28. [PMID: 27296654 DOI: 10.1016/j.neuro.2016.06.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 06/09/2016] [Accepted: 06/09/2016] [Indexed: 11/17/2022]
Abstract
Exposure of the developing brain to chlorpyrifos (CPF), an organophosphorus (OP) pesticide used extensively in agriculture worldwide, has been associated with increased prevalence of cognitive deficits in children, particularly boys. The present study was designed to test the hypothesis that cognitive deficits induced by prenatal exposure to sub-acute doses of CPF can be reproduced in precocial small species. To address this hypothesis, pregnant guinea pigs were injected daily with CPF (25mg/kg,s.c.) or vehicle (peanut oil) for 10days starting on presumed gestation day (GD) 53-55. Offspring were born around GD 65, weaned on postnatal day (PND) 20, and subjected to behavioral tests starting around PND 30. On the day of birth, butyrylcholinesterase (BuChE), an OP bioscavenger used as a biomarker of OP exposures, and acetylcholinesterase (AChE), a major molecular target of OP compounds, were significantly inhibited in the blood of CPF-exposed offspring. In their brains, BuChE, but not AChE, was significantly inhibited. Prenatal CPF exposure had no significant effect on locomotor activity or on locomotor habituation, a form of non-associative memory assessed in open fields. Spatial navigation in the Morris water maze (MWM) was found to be sexually dimorphic among guinea pigs, with males outperforming females. Prenatal CPF exposure impaired spatial learning more significantly among male than female guinea pigs and, consequently, reduced the sexual dimorphism of the task. The results presented here, which strongly support the test hypothesis, reveal that the guinea pig is a valuable animal model for preclinical assessment of the developmental neurotoxicity of OP pesticides. These findings are far reaching as they lay the groundwork for future studies aimed at identifying therapeutic interventions to treat and/or prevent the neurotoxic effects of CPF in the developing brain.
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Affiliation(s)
- Jacek Mamczarz
- Division of Translational Toxicology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Joseph D Pescrille
- Division of Translational Toxicology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Lisa Gavrushenko
- Division of Translational Toxicology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Richard D Burke
- Division of Translational Toxicology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - William P Fawcett
- Division of Translational Toxicology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Louis J DeTolla
- Program of Comparative Medicine and Departments of Pathology and Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Hegang Chen
- Division of Biostatistics and Bioinformatics, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Edna F R Pereira
- Division of Translational Toxicology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
| | - Edson X Albuquerque
- Division of Translational Toxicology, University of Maryland School of Medicine, Baltimore, MD 21201, United States.
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Engel SM, Bradman A, Wolff MS, Rauh VA, Harley KG, Yang JH, Hoepner LA, Barr DB, Yolton K, Vedar MG, Xu Y, Hornung RW, Wetmur JG, Chen J, Holland NT, Perera FP, Whyatt RM, Lanphear BP, Eskenazi B. Prenatal Organophosphorus Pesticide Exposure and Child Neurodevelopment at 24 Months: An Analysis of Four Birth Cohorts. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:822-30. [PMID: 26418669 PMCID: PMC4892910 DOI: 10.1289/ehp.1409474] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 09/23/2015] [Indexed: 05/03/2023]
Abstract
BACKGROUND Organophosphorus pesticides (OPs) are used in agriculture worldwide. Residential use was common in the United States before 2001. OBJECTIVES We conducted a pooled analysis of four birth cohorts (children's centers; n = 936) to evaluate associations of prenatal exposure to OPs with child development at 24 months. METHODS Using general linear models, we computed site-specific and pooled estimates of the association of total dialkyl (ΣDAP), diethyl (ΣDEP), and dimethylphosphate (ΣDMP) metabolite concentrations in maternal prenatal urine with mental and psychomotor development indices (MDI/PDI) and evaluated heterogeneity by children's center, race/ethnicity, and PON1 genotype. RESULTS There was significant heterogeneity in the center-specific estimates of association for ΣDAP and ΣDMP and the MDI (p = 0.09, and p = 0.05, respectively), as well as heterogeneity in the race/ethnicity-specific estimates for ΣDAP (p = 0.06) and ΣDMP (p = 0.02) and the MDI. Strong MDI associations in the CHAMACOS population per 10-fold increase in ΣDAP (β = -4.17; 95% CI: -7.00, -1.33) and ΣDMP (β = -3.64; 95% CI: -5.97, -1.32) were influential, as were associations among Hispanics (β per 10-fold increase in ΣDAP = -2.91; 95% CI: -4.71, -1.12). We generally found stronger negative associations of ΣDAP and ΣDEP with the 24-month MDI for carriers of the 192Q PON1 allele, particularly among blacks and Hispanics. CONCLUSIONS Data pooling was complicated by center-related differences in subject characteristics, eligibility, and changes in regulations governing residential use of OPs during the study periods. Pooled summary estimates of prenatal exposure to OPs and neurodevelopment should be interpreted with caution because of significant heterogeneity in associations by center, race/ethnicity, and PON1 genotype. Subgroups with unique exposure profiles or susceptibilities may be at higher risk for adverse neurodevelopment following prenatal exposure. CITATION Engel SM, Bradman A, Wolff MS, Rauh VA, Harley KG, Yang JH, Hoepner LA, Barr DB, Yolton K, Vedar MG, Xu Y, Hornung RW, Wetmur JG, Chen J, Holland NT, Perera FP, Whyatt RM, Lanphear BP, Eskenazi B. 2016. Prenatal organophosphorus pesticide exposure and child neurodevelopment at 24 months: an analysis of four birth cohorts. Environ Health Perspect 124:822-830; http://dx.doi.org/10.1289/ehp.1409474.
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Affiliation(s)
- Stephanie M. Engel
- Department of Epidemiology, UNC Gillings School of Global Public Health, Chapel Hill, North Carolina, USA
- Address correspondence to S. M. Engel, Department of Epidemiology CB#7435, UNC Gillings School of Global Public Health, Chapel Hill, NC 27599-7435 USA. Telephone: (919) 966-7435. E-mail:
| | - Asa Bradman
- Center for Children’s Environmental Health, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Mary S. Wolff
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Virginia A. Rauh
- Department of Population and Family Health, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - Kim G. Harley
- Center for Children’s Environmental Health, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Jenny H. Yang
- Department of Biostatistics, UNC Gillings School of Global Public Health, Chapel Hill, North Carolina, USA
| | - Lori A. Hoepner
- Department of Environmental Health Sciences, Columbia Center for Children’s Environmental Health, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - Dana Boyd Barr
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Kimberly Yolton
- Division of General and Community Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Michelle G. Vedar
- Center for Children’s Environmental Health, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Yingying Xu
- Division of General and Community Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Richard W. Hornung
- Division of General and Community Pediatrics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - James G. Wetmur
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Jia Chen
- Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Nina T. Holland
- Center for Children’s Environmental Health, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Frederica P. Perera
- Department of Environmental Health Sciences, Columbia Center for Children’s Environmental Health, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - Robin M. Whyatt
- Department of Environmental Health Sciences, Columbia Center for Children’s Environmental Health, Mailman School of Public Health, Columbia University, New York, New York, USA
| | | | - Brenda Eskenazi
- Center for Children’s Environmental Health, School of Public Health, University of California, Berkeley, Berkeley, California, USA
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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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De Felice A, Scattoni ML, Ricceri L, Calamandrei G. Prenatal exposure to a common organophosphate insecticide delays motor development in a mouse model of idiopathic autism. PLoS One 2015; 10:e0121663. [PMID: 25803479 PMCID: PMC4372449 DOI: 10.1371/journal.pone.0121663] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 01/27/2015] [Indexed: 11/18/2022] Open
Abstract
Autism spectrum disorders are characterized by impaired social and communicative skills and repetitive behaviors. Emerging evidence supported the hypothesis that these neurodevelopmental disorders may result from a combination of genetic susceptibility and exposure to environmental toxins in early developmental phases. This study assessed the effects of prenatal exposure to chlorpyrifos (CPF), a widely diffused organophosphate insecticide endowed with developmental neurotoxicity at sub-toxic doses, in the BTBR T+tf/J mouse strain, a validated model of idiopathic autism that displays several behavioral traits relevant to the autism spectrum. To this aim, pregnant BTBR mice were administered from gestational day 14 to 17 with either vehicle or CPF at a dose of 6 mg/kg/bw by oral gavages. Offspring of both sexes underwent assessment of early developmental milestones, including somatic growth, motor behavior and ultrasound vocalization. To evaluate the potential long-term effects of CPF, two different social behavior patterns typically altered in the BTBR strain (free social interaction with a same-sex companion in females, or interaction with a sexually receptive female in males) were also examined in the two sexes at adulthood. Our findings indicate significant effects of CPF on somatic growth and neonatal motor patterns. CPF treated pups showed reduced weight gain, delayed motor maturation (i.e., persistency of immature patterns such as pivoting at the expenses of coordinated locomotion) and a trend to enhanced ultrasound vocalization. At adulthood, CPF associated alterations were found in males only: the altered pattern of investigation of a sexual partner, previously described in BTBR mice, was enhanced in CPF males, and associated to increased ultrasonic vocalization rate. These findings strengthen the need of future studies to evaluate the role of environmental chemicals in the etiology of neurodevelopment disorders.
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Affiliation(s)
- Alessia De Felice
- Section of Neurotoxicology and Neuroendocrinology, Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, Rome, Italy
| | - Maria Luisa Scattoni
- Section of Neurotoxicology and Neuroendocrinology, Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy
| | - Laura Ricceri
- Section of Neurotoxicology and Neuroendocrinology, Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy
| | - Gemma Calamandrei
- Section of Neurotoxicology and Neuroendocrinology, Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Rome, Italy
- * E-mail:
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30
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D'Amato FR. Evaluation of social and nonsocial behaviors mediated by opioids in mouse pups. Methods Mol Biol 2015; 1230:313-322. [PMID: 25293338 DOI: 10.1007/978-1-4939-1708-2_27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The experimental approach to carry out a behavioral study involving opioids in mouse pups needs equipments and procedures different from those used for adult animals. Pups are immature at birth and only slowly acquire all the potentialities that characterize adult con-specifics. The standard and abnormal development of behavioral systems and their neural correlates can be followed during the first postnatal weeks, using appropriate methodologies that exploit characteristic pups' capabilities. Behavioral tests designed for pups to evaluate the activity and involvement of the opioid system, according to the well-known role of the system in adult animals, are described in this chapter.
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Affiliation(s)
- Francesca R D'Amato
- Cell Biology and Neurobiology Institute, CNR/IRCCS Santa Lucia Foundation, Via del Fosso di Fiorano 64, Rome, 00143, Italy,
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31
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Peris-Sampedro F, Salazar JG, Cabré M, Reverte I, Domingo JL, Sánchez-Santed F, Colomina MT. Impaired retention in AβPP Swedish mice six months after oral exposure to chlorpyrifos. Food Chem Toxicol 2014; 72:289-94. [DOI: 10.1016/j.fct.2014.07.036] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 07/22/2014] [Accepted: 07/28/2014] [Indexed: 02/07/2023]
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32
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Williams AL, DeSesso JM. Gestational/perinatal chlorpyrifos exposure is not associated with autistic-like behaviors in rodents. Crit Rev Toxicol 2014; 44:523-34. [PMID: 24861450 DOI: 10.3109/10408444.2014.907772] [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] [Indexed: 01/01/2023]
Abstract
Although animal models cannot exactly replicate human psychiatric disorders, they may be useful to investigate whether the behaviors associated with certain exposures in animals parallel those observed in people. According to the most current version of the Diagnostic and Statistical Manual of Mental Disorders, autism is diagnosed based on (1) persistent deficits in social communication and social interaction; and (2) the presence of restricted, repetitive patterns of behavior, interests and activities. To address whether developmental chlorpyrifos (CPF) exposure was associated with the development of autistic behaviors, a literature search was conducted to identify studies in rats and mice involving gestational or early postnatal exposure to CPF or CPF oxon (CPO, the active metabolite of CPF) and subsequent behavioral testing to assess behaviors related to autism. A total of 13 studies conducted in six different laboratories were identified. Analysis of these studies found that perinatal CPF exposure was generally associated with (1) no effect or increased social communications; (2) no effect or increased social encounters; (3) no effect, reduced stereotypies, or conflicting findings on stereotypic behaviors; and (4) no effect or increased preference for novelty and reduced anxiety in novel environments. These behavioral findings are generally inconsistent with the types of behaviors that would be expected in children with clinical autism. Based on the results of this analysis of rodent model studies involving CPF/CPO exposure, it cannot be concluded that gestational and/or perinatal CPF exposure is likely to be associated with the development of autism-like behaviors in humans.
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Sampino S, Juszczak GR, Zacchini F, Swiergiel AH, Modlinski JA, Loi P, Ptak GE. Grand-paternal age and the development of autism-like symptoms in mice progeny. Transl Psychiatry 2014; 4:e386. [PMID: 24780920 PMCID: PMC4012289 DOI: 10.1038/tp.2014.27] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 02/04/2014] [Accepted: 02/25/2014] [Indexed: 12/27/2022] Open
Abstract
Advanced paternal age (APA) contributes to the risk of autism spectrum disorders (ASDs) in children. In this study, we used a mouse model to investigate the effects of APA on behavioral features related to autistic syndromes (that is, social deficits, communication impairments and stereotypic/repetitive behaviors). We also examined whether such effects are transmitted across generations. To do this, males aged 15 months (APA) and 4 months (control) were bred with 4-month-old females, and the resulting offspring (F1) and their progeny (F2; conceived by 4-month-old parents) were tested for the presence and severity of ASD-like behaviors. Our results indicate that APA resulted in offspring that displayed distinctive symptoms of ASD. We found that both F1 conceived from old fathers and F2 derived from old grandfathers displayed increased ultrasound vocalization (USV) activity, decreased sociability, increased grooming activity and increased anxiety-like responses. Moreover, such abnormalities were partially transmitted to the second generation of mice, having APA grandfathers. In conclusion, our study suggests that the risk of ASD could develop over generations, consistent with heritable mutations and/or epigenetic alterations associated with APA.
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Affiliation(s)
- S Sampino
- Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy,Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzebiec, Poland
| | - G R Juszczak
- Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzebiec, Poland
| | - F Zacchini
- Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy
| | - A H Swiergiel
- Faculty of Biology, University of Gdansk, Gdansk, Poland,Department of Pharmacology, Toxicology and Neuroscience, Louisiana State University Health Sciences Center (LSUHSC), Shreveport, LA, USA
| | - J A Modlinski
- Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzebiec, Poland
| | - P Loi
- Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy
| | - G E Ptak
- Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy,Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzebiec, Poland,Faculty of Veterinary Medicine, University of Teramo, p.za aldo moro 45, 64100 Teramo, Italy. E-mail:
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Slotkin TA, Card J, Seidler FJ. Prenatal dexamethasone, as used in preterm labor, worsens the impact of postnatal chlorpyrifos exposure on serotonergic pathways. Brain Res Bull 2013; 100:44-54. [PMID: 24280657 DOI: 10.1016/j.brainresbull.2013.10.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 10/21/2013] [Accepted: 10/28/2013] [Indexed: 11/29/2022]
Abstract
This study explores how glucocorticoids sensitize the developing brain to the organophosphate pesticide, chlorpyrifos. Pregnant rats received a standard therapeutic dose (0.2mg/kg) of dexamethasone on gestational days 17-19; pups were given subtoxic doses of chlorpyrifos on postnatal days 1-4 (1mg/kg, <10% cholinesterase inhibition). We evaluated serotonin (5HT) synaptic function from postnatal day 30 to day 150, assessing the expression of 5HT receptors and the 5HT transporter, along with 5HT turnover (index of presynaptic impulse activity) in brain regions encompassing all the 5HT projections and cell bodies. These parameters are known targets for neurodevelopmental effects of dexamethasone and chlorpyrifos individually. In males, chlorpyrifos evoked overall elevations in the expression of 5HT synaptic proteins, with a progressive increase from adolescence to adulthood; this effect was attenuated by prenatal dexamethasone treatment. The chlorpyrifos-induced upregulation was preceded by deficits in 5HT turnover, indicating that the receptor upregulation was an adaptive response to deficient presynaptic activity. Turnover deficiencies were magnified by dexamethasone pretreatment, worsening the functional impairment caused by chlorpyrifos. In females, chlorpyrifos-induced receptor changes reflected relative sparing of adverse effects compared to males. Nevertheless, prenatal dexamethasone still worsened the 5HT turnover deficits and reduced 5HT receptor expression in females, demonstrating the same adverse interaction. Glucocorticoids are used in 10% of U.S. pregnancies, and are also elevated in maternal stress; accordingly, our results indicate that this group represents a large subpopulation that may have heightened vulnerability to developmental neurotoxicants such as the organophosphates.
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Affiliation(s)
- Theodore A Slotkin
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC, USA.
| | - Jennifer Card
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - Frederic J Seidler
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC, USA
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Foudoulakis M, Balaskas C, Csato A, Szentes C, Arapis G. Japanese quail acute exposure to methamidophos: experimental design, lethal, sub-lethal effects and cholinesterase biochemical and histochemical expression. THE SCIENCE OF THE TOTAL ENVIRONMENT 2013; 450-451:334-347. [PMID: 23146311 DOI: 10.1016/j.scitotenv.2012.10.066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2012] [Revised: 10/14/2012] [Accepted: 10/15/2012] [Indexed: 06/01/2023]
Abstract
We exposed the Japanese quail (Coturnix coturnix japonica) to the organophosphate methamidophos using acute oral test. Mortality and sub-lethal effects were recorded in accordance to internationally accepted protocols. In addition cholinesterases were biochemically estimated in tissues of the quail: brain, liver and plasma. Furthermore, brain, liver and duodenum cryostat sections were processed for cholinesterase histochemistry using various substrates and inhibitors. Mortalities occurred mainly in the first 1-2h following application. Sub-lethal effects, such as ataxia, ruffled feathers, tremor, salivation and reduced or no reaction to external stimuli were observed. Biochemical analysis in the brain, liver and plasma indicates a strong cholinesterase dependent inhibition with respect to mortality and sub-lethal effects of the quail. The histochemical staining also indicated a strong cholinesterase inhibition in the organs examined and the analysis of the stained sections allowed for an estimation and interpretation of the intoxication effects of methamidophos, in combination with tissue morphology visible by Haematoxylin and Eosin staining. We conclude that the use of biochemistry and histochemistry for the biomarker cholinesterase, may constitute a significantly novel approach for understanding the results obtained by the acute oral test employed in order to assess the effects of methamidophos and other chemicals known to inhibit this very important nervous system enzyme.
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Affiliation(s)
- Manousos Foudoulakis
- Laboratory of Ecology and Environmental Sciences, Agricultural University of Athens, Iera Odos 75, Athens 11854, Greece.
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36
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Terranova ML, Laviola G. Scoring of social interactions and play in mice during adolescence. ACTA ACUST UNITED AC 2013; Chapter 13:Unit13.10. [PMID: 23045110 DOI: 10.1002/0471140856.tx1310s26] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This unit provides a description of methods that have proven useful in characterizing amicable and playful interactions of developing mice. Such a procedure can be used to evaluate the effects of perinatal and/or ongoing treatments on the social performance of periadolescent subjects of either or both sexes. It can also be complemented by the use of specific acute drug challenges, which can throw light on possible alterations of the subserving neurochemical systems. Basically, it consists of video recording brief sessions of spontaneous pair interactions and their subsequent observation and scoring according to a detailed mouse ethogram. The protocol is quite sensitive to subtle behavioral effects, which could be undetectable by other means, and it is most useful when repeated over several days to draw an ontogenetic profile. Critical parameters that must be considered when planning, e.g., sample size and timing of observations, are discussed in detail, along with the key issue of controlling for litter effects.
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Naseh M, Vatanparast J, Baniasadi M, Hamidi GA. Alterations in nitric oxide synthase-expressing neurons in the forebrain regions of rats after developmental exposure to organophosphates. Neurotoxicol Teratol 2013; 37:23-32. [PMID: 23416429 DOI: 10.1016/j.ntt.2013.02.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Revised: 01/26/2013] [Accepted: 02/02/2013] [Indexed: 12/15/2022]
Abstract
Several mechanisms have been addressed as contributors to the long lasting behavioral deficits after developmental exposure to organophosphate (OP) compounds. Here, the effects of developmental exposure to two common OP insecticides, chlorpyrifos (CPF) and diazinon (DZN), on nitric oxide synthase (NOS)-expressing neurons in the rat forebrain are reported. A daily dose of 1mg/kg of either CPF or DZN was administered to rats during gestational days 15-18 or postnatal days (PND) 1-4. We then assessed NADPH-diaphorase and neuronal NOS (nNOS) immunohistochemistry in forebrain sections on different postnatal days. Prenatal exposure to CPF and DZN induced a transient reduction of NADPH-d(+)/nNOS-immunoreactive (IR) neurons in most cortical regions on PND 4 but exceptionally increased them in the entorhinal/piriform cortex. On PND 15, NADPH-d(+)/nNOS-IR neurons showed morphological abnormalities within entorhinal/piriform cortex of the rats that gestationally exposed to CPF. Postnatal exposure to CPF and DZN did not induce widespread effects on the number of NADPH-d(+)/nNOS-IR neurons on PNDs 7 and 15 but significantly reduced them in most cortical regions and hippocampal subfields on PND 60. The OPs affected NADPH-d(+)/nNOS-IR neurons in a sex independent manner and apparently spared them in the striatum. While the NADPH-d reactivity of microvessels was normally diminished by age, OP treated rats evidently preserved the NADPH-d reactivity of microvessels in the cerebral cortex and hippocampus. The effects of OPs on NADPH-d(+)/nNOS-IR neurons may contribute to the long-lasting behavioral outcomes and expand the neurotransmitter system that need to be considered in OP neurotoxicity evaluations.
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Affiliation(s)
- Maryam Naseh
- Department of Biology, College of Sciences, Shiraz University, Shiraz, Iran
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Vatanparast J, Naseh M, Baniasadi M, Haghdoost-Yazdi H. Developmental exposure to chlorpyrifos and diazinon differentially affect passive avoidance performance and nitric oxide synthase-containing neurons in the basolateral complex of the amygdala. Brain Res 2012; 1494:17-27. [PMID: 23219576 DOI: 10.1016/j.brainres.2012.11.049] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 11/07/2012] [Accepted: 11/28/2012] [Indexed: 01/14/2023]
Abstract
Chronic exposure to low doses of organophosphates during brain development can induce persistent neurochemical and behavioral effects. This study sought to determine the long-lasting effects of developmental exposure to chlorpyrifos (CPF) and diazinon (DZN) on passive avoidance (PA) performance and neuronal nitric oxide synthase (nNOS)-containing neurons in the subnuclei within basolateral complex of amygdala (BLC). Developing rats were exposed to daily dose (1mg/kg) of CPF or DZN during gestational days 15-18 and postnatal days (PND) 1-4. PA performance was assessed in young adulthood (PND 60). Brain sections were also processed by NADPH-diaphorase (NADPH-d) and nNOS immunohistochemistry. Gestational exposure to CPF increased NADPH-d(+)/nNOS-immunoreactive (IR) neurons within the basolateral nucleus (BL) and medial paracapsular intercalated cluster, which was along with PA retention impairment in both male and female rats. Prenatal exposure to DZN did not significantly change the number of NADPH-d(+)/nNOS-IR neurons in the BLC while impaired PA retention in females. Postnatal exposure to CPF decreased NADPH-d(+)/NOS-IR neurons in the BL without affecting PA performance. Exposure to DZN during early postnatal period impaired PA retention in both sexes, albeit to a lesser extent in females, and was along with a considerable sex independent reduction of NADPH-d(+)/NOS-IR neurons in all BLC subnuclei. Our data suggest that developmental exposure to apparently subtoxic dose of CPF and DZN elicit long-lasting impairment in PA retention that are associated, but not necessarily correlated with effects on NADPH-d(+)/NOS-IR neurons in BLC of the amygdala.
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Affiliation(s)
- Jafar Vatanparast
- Department of Biology, College of Sciences, Shiraz University, Shiraz 71454, Iran.
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Sex dimorphic behaviors as markers of neuroendocrine disruption by environmental chemicals: The case of chlorpyrifos. Neurotoxicology 2012; 33:1420-1426. [DOI: 10.1016/j.neuro.2012.08.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 08/06/2012] [Accepted: 08/22/2012] [Indexed: 11/18/2022]
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Schwartzer JJ, Koenig CM, Berman RF. Using mouse models of autism spectrum disorders to study the neurotoxicology of gene-environment interactions. Neurotoxicol Teratol 2012; 36:17-35. [PMID: 23010509 DOI: 10.1016/j.ntt.2012.08.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 08/28/2012] [Accepted: 08/30/2012] [Indexed: 10/27/2022]
Abstract
To better study the role of genetics in autism, mouse models have been developed which mimic the genetics of specific autism spectrum and related disorders. These models have facilitated research on the role genetic susceptibility factors in the pathogenesis of autism in the absence of environmental factors. Inbred mouse strains have been similarly studied to assess the role of environmental agents on neurodevelopment, typically without the complications of genetic heterogeneity of the human population. What has not been as actively pursued, however, is the methodical study of the interaction between these factors (e.g., gene and environmental interactions in neurodevelopment). This review suggests that a genetic predisposition paired with exposure to environmental toxicants plays an important role in the etiology of neurodevelopmental disorders including autism, and may contribute to the largely unexplained rise in the number of children diagnosed with autism worldwide. Specifically, descriptions of the major mouse models of autism and toxic mechanisms of prevalent environmental chemicals are provided followed by a discussion of current and future research strategies to evaluate the role of gene and environment interactions in neurodevelopmental disorders.
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Affiliation(s)
- Jared J Schwartzer
- Department of Psychiatry and Behavioral Sciences, MIND Institute, University of California, Davis, Davis, CA 95618, United States.
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Saunders M, Magnanti BL, Correia Carreira S, Yang A, Alamo-Hernández U, Riojas-Rodriguez H, Calamandrei G, Koppe JG, Krayer von Krauss M, Keune H, Bartonova A. Chlorpyrifos and neurodevelopmental effects: a literature review and expert elicitation on research and policy. Environ Health 2012; 11 Suppl 1:S5. [PMID: 22759505 PMCID: PMC3388448 DOI: 10.1186/1476-069x-11-s1-s5] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
BACKGROUND Organophosphate pesticides are widely used on food crops grown in the EU. While they have been banned from indoor use in the US for a decade due to adverse health effects, they are still the most prevalent pesticides in the EU, with Chlorpyrifos (CPF) being the most commonly applied. It has been suggested CPF affects neurodevelopment even at levels below toxicity guidelines. Younger individuals may be more susceptible than adults due to biological factors and exposure settings. METHODS A literature review was undertaken to assess the evidence for CPF contributing to neurodevelopmental disorders in infants and children. Other literature was consulted in order to formulate a causal chain diagram showing the origins, uptake, and neurological effects of animal and human exposure to CPF.The causal chain diagram and a questionnaire were distributed online to scientific experts who had published in relevant areas of research. They were asked to assess their confidence levels on whether CPF does in fact contribute to adverse neurodevelopment outcomes and rate their confidence in the scientific evidence. A second questionnaire queried experts as to which kind of policy action they consider justifiable based on current knowledge. In a special workshop session at the EuroTox congress in Dresden in 2009 the results of both questionnaires were further discussed with invited experts, as a basis for a policy brief with main messages for policy makers and stakeholders. RESULTS Most experts who responded to the first questionnaire felt that there was already enough evidence to support a ban on indoor uses of CPF in the EU. However, most felt additional research is still required in several areas. The responses from the first questionnaire were used to formulate the second questionnaire addressing the feasibility of government action. In turn, these expert participants were invited to attend a special session at the EuroTox congress in Dresden in 2009. CONCLUSIONS Some of the evidence that CPF contributes to neurodevelopmental disorders is still disputed among experts, and the overall sense is that further research and public awareness are warranted. There have been campaigns in North America making the potential exposure concerns known, but such information is not widely known in the EU. The ability of government action to produce change is strongly felt in some quarters while others believe better knowledge of consumer use trends would have a greater impact.
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Affiliation(s)
| | | | | | - Aileen Yang
- NILU - Norwegian Institute for Air Research, Kjeller, Norway
| | | | | | | | | | | | - Hans Keune
- Research Institute for Nature and Forest (INBO), Brussels; Centre of Expertise for Environment and Health, Faculty of Political and Social Sciences, University of Antwerp; naXys, Namur Center for Complex Systems, University of Namur, Belgium
| | - Alena Bartonova
- NILU - Norwegian Institute for Air Research, Kjeller, Norway
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Giordano G, Costa LG. Developmental neurotoxicity: some old and new issues. ISRN TOXICOLOGY 2012; 2012:814795. [PMID: 23724296 PMCID: PMC3658697 DOI: 10.5402/2012/814795] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 04/29/2012] [Indexed: 11/23/2022]
Abstract
The developing central nervous system is often more vulnerable to injury than the adult one. Of the almost 200 chemicals known to be neurotoxic, many are developmental neurotoxicants. Exposure to these compounds in utero or during childhood can contribute to a variety of neurodevelopmental and neurological disorders. Two established developmental neurotoxicants, methylmercury and lead, and two classes of chemicals, the polybrominated diphenyl ether flame retardants and the organophosphorus insecticides, which are emerging as potential developmental neurotoxicants, are discussed in this paper. Developmental neurotoxicants may also cause silent damage, which would manifest itself only as the individual ages, and may contribute to neurodegenerative diseases such as Parkinson's or Alzheimer's diseases. Guidelines for developmental neurotoxicity testing have been implemented, but there is still room for their improvement and for searching and validating alternative testing approaches.
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Affiliation(s)
- Gennaro Giordano
- Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt Way NE, Suite 100, Seattle, WA 98105, USA
| | - Lucio G. Costa
- Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt Way NE, Suite 100, Seattle, WA 98105, USA
- Department of Human Anatomy, Pharmacology and Forensic Science, University of Parma Medical School, 43121 Parma, Italy
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Frye CA, Bo E, Calamandrei G, Calzà L, Dessì-Fulgheri F, Fernández M, Fusani L, Kah O, Kajta M, Le Page Y, Patisaul HB, Venerosi A, Wojtowicz AK, Panzica GC. Endocrine disrupters: a review of some sources, effects, and mechanisms of actions on behaviour and neuroendocrine systems. J Neuroendocrinol 2012; 24:144-59. [PMID: 21951193 PMCID: PMC3245362 DOI: 10.1111/j.1365-2826.2011.02229.x] [Citation(s) in RCA: 273] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Some environmental contaminants interact with hormones and may exert adverse consequences as a result of their actions as endocrine disrupting chemicals (EDCs). Exposure in people is typically a result of contamination of the food chain, inhalation of contaminated house dust or occupational exposure. EDCs include pesticides and herbicides (such as dichlorodiphenyl trichloroethane or its metabolites), methoxychlor, biocides, heat stabilisers and chemical catalysts (such as tributyltin), plastic contaminants (e.g. bisphenol A), pharmaceuticals (i.e. diethylstilbestrol; 17α-ethinylestradiol) or dietary components (such as phytoestrogens). The goal of this review is to address the sources, effects and actions of EDCs, with an emphasis on topics discussed at the International Congress on Steroids and the Nervous System. EDCs may alter reproductively-relevant or nonreproductive, sexually-dimorphic behaviours. In addition, EDCs may have significant effects on neurodevelopmental processes, influencing the morphology of sexually-dimorphic cerebral circuits. Exposure to EDCs is more dangerous if it occurs during specific 'critical periods' of life, such as intrauterine, perinatal, juvenile or puberty periods, when organisms are more sensitive to hormonal disruption, compared to other periods. However, exposure to EDCs in adulthood can also alter physiology. Several EDCs are xenoestrogens, which can alter serum lipid concentrations or metabolism enzymes that are necessary for converting cholesterol to steroid hormones. This can ultimately alter the production of oestradiol and/or other steroids. Finally, many EDCs may have actions via (or independent of) classic actions at cognate steroid receptors. EDCs may have effects through numerous other substrates, such as the aryl hydrocarbon receptor, the peroxisome proliferator-activated receptor and the retinoid X receptor, signal transduction pathways, calcium influx and/or neurotransmitter receptors. Thus, EDCs, from varied sources, may have organisational effects during development and/or activational effects in adulthood that influence sexually-dimorphic, reproductively-relevant processes or other functions, by mimicking, antagonising or altering steroidal actions.
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Affiliation(s)
- C A Frye
- Department of Psychology, The University at Albany-SUNY, Albany, NY 12222, USA.
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Li AA, Lowe KA, McIntosh LJ, Mink PJ. Evaluation of epidemiology and animal data for risk assessment: chlorpyrifos developmental neurobehavioral outcomes. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2012; 15:109-184. [PMID: 22401178 PMCID: PMC3386549 DOI: 10.1080/10937404.2012.645142] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Developmental neurobehavioral outcomes attributed to exposure to chlorpyrifos (CPF) obtained from epidemiologic and animal studies published before June 2010 were reviewed for risk assessment purposes. For epidemiological studies, this review considered (1) overall strength of study design, (2) specificity of CPF exposure biomarkers, (3) potential for bias, and (4) Hill guidelines for causal inference. In the case of animal studies, this review focused on evaluating the consistency of outcomes for developmental neurobehavioral endpoints from in vivo mammalian studies that exposed dams and/or offspring to CPF prior to weaning. Developmental neuropharmacologic and neuropathologic outcomes were also evaluated. Experimental design and methods were examined as part of the weight of evidence. There was insufficient evidence that human developmental exposures to CPF produce adverse neurobehavioral effects in infants and children across different cohort studies that may be relevant to CPF exposure. In animals, few behavioral parameters were affected following gestational exposures to 1 mg/kg-d but were not consistently reported by different laboratories. For postnatal exposures, behavioral effects found in more than one study at 1 mg/kg-d were decreased errors on a radial arm maze in female rats and increased errors in males dosed subcutaneously from postnatal day (PND) 1 to 4. A similar finding was seen in rats exposed orally from PND 1 to 21 with incremental dose levels of 1, 2, and 4 mg/kg-d, but not in rats dosed with constant dose level of 1 mg/kg-d. Neurodevelopmental behavioral, pharmacological, and morphologic effects occurred at doses that produced significant brain or red blood cell acetylcholinesterase inhibition in dams or offspring.
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Affiliation(s)
- Abby A Li
- Exponent Health Sciences Group, Menlo Park, California, USA.
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Lin T, Duek O, Dori A, Kofman O. Differential long term effects of early diisopropylfluorophosphate exposure in Balb/C and C57Bl/J6 mice. Int J Dev Neurosci 2011; 30:113-20. [PMID: 22197972 DOI: 10.1016/j.ijdevneu.2011.12.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 12/01/2011] [Accepted: 12/08/2011] [Indexed: 11/17/2022] Open
Abstract
The long-term effect of postnatal administration of a sub-toxic dose of the irreversible acetylcholinesterase inhibitor diisopropylfluorophosphate (DFP) on depression and anxiety behavior was compared in two strains of inbred mice. C57BL/6J and Balb/C mice were injected for 7 consecutive days with either 1 mg/kg DFP or saline on postnatal days 14-20. Mice were tested at age 3-4 months for initial and learned anxiety using double-exposure elevated plus maze and to a novel enclosed environment. Depression was assayed using the sweet preference model of anhedonia and the forced swim test for despair. Postnatal DFP pretreatment led to less activity and more immobility in the elevated plus maze in both mouse strains in the first session. The effect was attenuated in the second session in the C57BL/6J strain but not the Balb/C strain. DFP did not affect the sweet preference or forced swim tests, suggesting a dissociation between the long-term effects of DFP on immobility in the context of approach-avoidance conflict (elevated plus maze) versus despair (forced swim).
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Affiliation(s)
- Tamar Lin
- Department of Psychology and Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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46
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Prueitt RL, Goodman JE, Bailey LA, Rhomberg LR. Hypothesis-based weight-of-evidence evaluation of the neurodevelopmental effects of chlorpyrifos. Crit Rev Toxicol 2011; 41:822-903. [PMID: 22085162 DOI: 10.3109/10408444.2011.616877] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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47
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Anxiety in adult female mice following perinatal exposure to chlorpyrifos. Neurotoxicol Teratol 2010; 32:234-9. [PMID: 19716890 DOI: 10.1016/j.ntt.2009.08.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Revised: 08/19/2009] [Accepted: 08/20/2009] [Indexed: 11/20/2022]
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Gestational exposure to the organophosphate chlorpyrifos alters social-emotional behaviour and impairs responsiveness to the serotonin transporter inhibitor fluvoxamine in mice. Psychopharmacology (Berl) 2010; 208:99-107. [PMID: 19921154 DOI: 10.1007/s00213-009-1713-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Accepted: 10/23/2009] [Indexed: 12/17/2022]
Abstract
BACKGROUND The organophosphate chlorpyrifos (CPF) is a pesticide largely used worldwide. Studies from animal models indicate that CPF exposure during development at low doses can target different neurotransmitter systems in the absence of overt cholinergic effects. METHODS Late gestational exposure (gestational days 14-17) to CPF at the dose of 6 mg/kg was evaluated in CD-1 mice at adulthood. Neurobehavioural effects likely involving serotonin (5-hydroxytryptamine, 5HT) transmission were assessed both in males and females, through the light-dark exploration test to assess CPF effects on anxiety profiles and the forced swimming test to evaluate the response to the 5HT transporter (5HTT) inhibitor fluvoxamine (30 mg/kg). In females only, we evaluated the effects of gestational exposure to CPF on maternal aggression, under basal condition or after injection of fluvoxamine. RESULTS Gestational CPF exposure increased anxiety levels only in female mice, as shown by the augmented thigmotaxis behaviour and the lower latency to enter in the dark compartment. In the forced swimming test, no differences between CPF and control mice were found when assessed under basal condition (saline administration), but both male and female CPF mice missed to show the typical behavioural effects of the 5HTT inhibitor fluvoxamine. During maternal aggression, CPF females showed lower propensity to and intensity of aggressive behaviour, together with mild decreased responsiveness to fluvoxamine administration. CONCLUSIONS Overall, the present results confirm a specific and sex-dependent vulnerability of affective/emotional domains to developmental CPF exposure. Furthermore, data provide clear indication on the disrupting effects of prenatal CPF on serotoninergic transmission.
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Kozawa K, Aoyama Y, Mashimo S, Kimura H. Toxicity and actual regulation of organophosphate pesticides. TOXIN REV 2009. [DOI: 10.3109/15569540903297808] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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50
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Chen TH, Gross JA, Karasov WH. Chronic exposure to pentavalent arsenic of larval leopard frogs (Rana pipiens): bioaccumulation and reduced swimming performance. ECOTOXICOLOGY (LONDON, ENGLAND) 2009; 18:587-593. [PMID: 19396542 DOI: 10.1007/s10646-009-0316-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Accepted: 04/09/2009] [Indexed: 05/27/2023]
Abstract
Arsenic (As) is mainly released to the environment from anthropogenic sources, with inorganic pentavalent As (As [V]) predominant in surface water. In this study, Rana pipiens were exposed to As (V) in water at environmentally relevant concentrations (control, 10, 20, 150, 500, and 1,000 microg l(-1)) in a static-renewal system from post-hatch stage through metamorphosis for 113 days. There was no significant effect of As exposure on tadpole survival, growth, and percent metamorphosis. Maximum swimming speed was significantly slower in the As-treated groups compared with the control. During the period of tail resorption (Gosner stage 42-46), no significant differences in age at metamorphosis, survival, length of tail resorption period, snout-vent length of metamorphs, and sex ratio were found among treatments. Whole body As concentrations ranged from <0.6 to 5.31 mg kg(-1) dry mass, and were significantly higher in the 150, 500, and 1,000 microg l(-1) treatments than the control. Based on our data, larval tissue concentrations of As close to that reported in previous field studies were not associated with any significant effects except decreased tadpole swimming speed.
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Affiliation(s)
- Te-Hao Chen
- Department of Biology, National Museum of Marine Biology and Aquarium, Pingtung, Taiwan.
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