1
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Napierkowska S, Froment P, Kowalczyk A, Pamuła J, Birger M, Niżański W, Partyka A. The neonicotinoid, imidacloprid, disrupt the chicken sperm quality through calcium efflux. Poult Sci 2024; 103:103959. [PMID: 38943803 PMCID: PMC11261453 DOI: 10.1016/j.psj.2024.103959] [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: 04/04/2024] [Revised: 06/04/2024] [Accepted: 06/04/2024] [Indexed: 07/01/2024] Open
Abstract
Imidacloprid (IMI), an insecticide from the neonicotinoid group widely used in agriculture, has drawn attention due to its potential harmful effects on non-target species, including bird populations. In the present work, we investigated the effect of IMI on avian semen by in vitro exposure of rooster spermatozoa to this pesticide. The semen was collected twice a week. Samples collected on one day were pooled and incubated with the following IMI concentrations: 0 mM, 0.5 mM, 5 mM, 10 mM, and 50 mM at 36°C for 3 h. Comprehensive semen analysis was carried out after 1 h and 3 h of incubation, evaluating sperm motility parameters with the CASA system and using flow cytometry to assess membrane integrity, mitochondrial activity, acrosome integrity, chromatin structure, intracellular calcium level and apoptosis markers such as: early apoptosis and caspase activation and lipid peroxidation. The results of the first experiment suggest that low concentrations of IMI have a different effect on sperm motility compared to higher concentrations. In IMI samples, we also observed a lower percentage of cells with a high level of calcium ions compared to the control, and a lower level of lipid peroxidation. We concluded that IMI may act as a blocker of calcium channels, preventing the influx of these ions into the cell. To confirm this mechanism, we conducted a second experiment with calcium channel blockers: SNX 325, MRS-1845, and Nifedipine. The results of this experiment confirmed that the mechanism of action of IMI largely relies on the blockade of calcium channels in rooster sperm. Blocking the influx of calcium ions into the cell prevents the formation of Ca²⁺-dependent pores, thereby preventing an increase in cell membrane permeability, ultimately blocking early apoptosis and lipid peroxidation in chicken spermatozoa.
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Affiliation(s)
- Skarlet Napierkowska
- Wroclaw University of Environmental and Life Science, Department of Reproduction and Clinic of Farm Animal, Wrocław, Poland
| | - Pascal Froment
- INRAE, UMR85 Physiologie de la Reproduction et des Comportements, Nouzilly, France
| | - Artur Kowalczyk
- Wroclaw University of Environmental and Life Science, Institute of Animal Breeding, Wrocław, Poland
| | - Jędrzej Pamuła
- Wroclaw University of Environmental and Life Science, Department of Reproduction and Clinic of Farm Animal, Wrocław, Poland
| | - Mariusz Birger
- Wroclaw University of Environmental and Life Science, Department of Reproduction and Clinic of Farm Animal, Wrocław, Poland
| | - Wojciech Niżański
- Wroclaw University of Environmental and Life Science, Department of Reproduction and Clinic of Farm Animal, Wrocław, Poland
| | - Agnieszka Partyka
- Wroclaw University of Environmental and Life Science, Department of Reproduction and Clinic of Farm Animal, Wrocław, Poland.
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2
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Hirano T, Ohno S, Ikenaka Y, Onaru K, Kubo S, Miyata Y, Maeda M, Mantani Y, Yokoyama T, Nimako C, Yohannes YB, Nakayama SMM, Ishizuka M, Hoshi N. Quantification of the tissue distribution and accumulation of the neonicotinoid pesticide clothianidin and its metabolites in maternal and fetal mice. Toxicol Appl Pharmacol 2024; 484:116847. [PMID: 38336252 DOI: 10.1016/j.taap.2024.116847] [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: 12/03/2023] [Revised: 01/28/2024] [Accepted: 02/05/2024] [Indexed: 02/12/2024]
Abstract
Neonicotinoids (NNs) are commonly used pesticides that have a selective agonistic action on insect nicotinic acetylcholine receptors. Recent evidence has shown that NNs have adverse effects in the next generation of mammals, but it remains unclear how NNs transferred from dams to fetuses are distributed and accumulated in fetal tissues. Here, we aimed to clarify the tissue distribution and accumulation properties of the NN clothianidin (CLO) and its 6 metabolites in 7 tissues and blood in both dams and fetuses of mice administered CLO for a single day or for 9 consecutive days. The results showed that the total concentrations of CLO-related compounds in the brain and kidney were higher in fetuses than in dams, whereas in the liver, heart, and blood they were lower in fetuses. The multi-day administration increased the total levels in heart and blood only in the fetuses of the single administration group. In addition, dimethyl metabolites of CLO showed fetus/dam ratios >1 in some tissues, suggesting that fetuses have higher accumulation property and are thus at higher risks of exposure to CLO-related compounds than dams. These findings revealed differences in the tissue-specific distribution patterns of CLO and its metabolites between dams and fetuses, providing new insights into the assessment of the developmental toxicity of NNs.
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Affiliation(s)
- Tetsushi Hirano
- Faculty of Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama, Toyama 930-0194, Japan.
| | - Shuji Ohno
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan
| | - Yoshinori Ikenaka
- Translational Research Unit, Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan; Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa; One Health Research Center, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan; Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
| | - Kanoko Onaru
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan
| | - Shizuka Kubo
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan
| | - Yuka Miyata
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan
| | - Mizuki Maeda
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan
| | - Youhei Mantani
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan
| | - Toshifumi Yokoyama
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan
| | - Collins Nimako
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
| | - Yared Beyene Yohannes
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
| | - Shouta M M Nakayama
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
| | - Mayumi Ishizuka
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
| | - Nobuhiko Hoshi
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan.
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3
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Carneiro LS, Martinez LC, Oliveira AHD, Cossolin JFS, Resende MTCSD, Gonçalves WG, Medeiros-Santana L, Serrão JE. Acute oral exposure to imidacloprid induces apoptosis and autophagy in the midgut of honey bee Apis mellifera workers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 815:152847. [PMID: 34995599 DOI: 10.1016/j.scitotenv.2021.152847] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/19/2021] [Accepted: 12/28/2021] [Indexed: 06/14/2023]
Abstract
The honey bee Apis mellifera is an important pollinator that increases the yield and quality of crops. In recent years, honey bee populations have declined in some parts of the world, which has been associated with several causes, including pesticides used in agriculture. Neonicotinoids are neurotoxic insecticides widely used in the world with systemic action mode contaminating nectar and pollen that may be consumed by bees. This study evaluated the side effects of imidacloprid in the midgut of A. mellifera after acute oral exposure. Toxicity, histopathology, cytotoxicity, and expression of autophagy-related gene atg1 were evaluated in honey bee workers orally exposed to imidacloprid. The estimated imidacloprid LC50 was 1.44 mg L-1. The midgut epithelium of bees fed on imidacloprid LC50 has the occurrence of cytoplasm vacuoles, enlarged intercellular spaces, disorganization of the striated border, and nuclear pyknosis, with an organ injury index that increases with time exposure. The midgut digestive cells of treated bees have apical protrusions, damaged mitochondria, and autophagosomes that were characterized for content with organelle debris and high expression of atg1. These features indicate the occurrence of high cell death in the midgut of workers exposed to imidacloprid, which may affect the digestibility the physiology of the insect.
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Affiliation(s)
- Lenise Silva Carneiro
- Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Luis Carlos Martinez
- Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | | | | | | | - Wagner Gonzanga Gonçalves
- Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil
| | - Luanda Medeiros-Santana
- Instituto de Ciências Biológicas e da Saúde, Universidade Federal de Viçosa - campus Rio Paranaíba, Rio Paranaíba, Minas Gerais 38810-00, Brazil
| | - José Eduardo Serrão
- Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil.
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4
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Nishi M, Sugio S, Hirano T, Kato D, Wake H, Shoda A, Murata M, Ikenaka Y, Tabuchi Y, Mantani Y, Yokoyama T, Hoshi N. Elucidation of the neurological effects of clothianidin exposure at the no-observed-adverse-effect level (NOAEL) using two-photon microscopy in vivo imaging. J Vet Med Sci 2022; 84:585-592. [PMID: 35264496 PMCID: PMC9096047 DOI: 10.1292/jvms.22-0013] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Neonicotinoid pesticides (NNs) cause behavioral abnormalities in mammals, raising
concerns about their effects on neural circuit activity. We herein examined the
neurological effects of the NN clothianidin (CLO) by in vivo
Ca2+ imaging using two-photon microscopy. Mice were fed the
no-observed-adverse-effect-level (NOAEL) dose of CLO for 2 weeks and their neuronal
activity in the primary somatosensory cortex (S1) was observed weekly for 2 weeks. CLO
exposure caused a sustained influx of Ca2+ in neurons in the S1 2/3 layers,
indicating hyperactivation of neurons. In addition, microarray gene expression analysis
suggested the induction of neuroinflammation and changes in synaptic activity. These
results demonstrate that exposure to the NOAEL dose of CLO can overactivate neurons and
disrupt neuronal homeostasis.
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Affiliation(s)
- Misaki Nishi
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University
| | - Shouta Sugio
- Department of Anatomy and Molecular Cell Biology, Graduate School of Medicine, Nagoya University
| | | | - Daisuke Kato
- Department of Anatomy and Molecular Cell Biology, Graduate School of Medicine, Nagoya University
| | - Hiroaki Wake
- Department of Anatomy and Molecular Cell Biology, Graduate School of Medicine, Nagoya University
| | - Asuka Shoda
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University
| | - Midori Murata
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University
| | - Yoshinori Ikenaka
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University.,Translational Research Unit, Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Hokkaido University.,One Health Research Center, Hokkaido University.,Water Research Group, Unit for Environmental Sciences and Management, North-West University
| | | | - Youhei Mantani
- Laboratory of Histophysiology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University
| | - Toshifumi Yokoyama
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University
| | - Nobuhiko Hoshi
- Laboratory of Animal Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University
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5
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Membrane polarization in non-neuronal cells as a potential mechanism of metabolic disruption by depolarizing insecticides. Food Chem Toxicol 2022; 160:112804. [PMID: 34990786 DOI: 10.1016/j.fct.2021.112804] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 12/22/2021] [Accepted: 12/31/2021] [Indexed: 01/01/2023]
Abstract
A significant rise in the incidence of obesity and type 2 diabetes has occurred worldwide in the last two decades. Concurrently, a growing body of evidence suggests a connection between exposure to environmental pollutants, particularly insecticides, and the development of obesity and type 2 diabetes. This review summarizes key evidence of (1) the presence of different types of neuronal receptors - target sites for neurotoxic insecticides - in non-neuronal cells, (2) the activation of these receptors in non-neuronal cells by membrane-depolarizing insecticides, and (3) changes in metabolic functions, including lipid and glucose accumulation, associated with changes in membrane potential. Based on these findings, we propose that changes in membrane potential (Vmem) by certain insecticides serve as a novel regulator of lipid and glucose metabolism in non-excitable cells associated with obesity and type 2 diabetes.
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6
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Nimako C, Ikenaka Y, Akoto O, Fujioka K, Taira K, Arizono K, Kato K, Takahashi K, Nakayama SMM, Ichise T, Ishizuka M. Simultaneous quantification of imidacloprid and its metabolites in tissues of mice upon chronic low-dose administration of imidacloprid. J Chromatogr A 2021; 1652:462350. [PMID: 34198103 DOI: 10.1016/j.chroma.2021.462350] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/03/2021] [Accepted: 06/08/2021] [Indexed: 01/07/2023]
Abstract
This study aimed to (i) develop a sensitive method for simultaneous detection and quantification of imidacloprid (IMI) and seven of its metabolites in tissue specimens, and to (ii) determine the biodistribution of the IMI compounds in tissues of C57BL/6J male mice; after exposure to 0.6 mg/kg bw/day of IMI (10% of no observable adverse effect level of IMI) through a powdered diet for 24 weeks. We successfully developed a method which was accurate (recoveries were ≥ 70% for most compounds), sensitive (LODs ≤ 0.47 ng/mL and LOQs ≤ 1.43 ng/mL were recorded for all detected compounds, R2 ≥ 0.99) and precise (RSDs ≤ 20%) for routine analysis of IMI and seven of its metabolites in blood and various tissue matrices. After bio-distributional analysis, IMI and five of its metabolites were detected in mice. Brain, testis, lung, kidney, inguinal white adipose tissue and gonadal white adipose tissue mainly accumulated IMI, blood and mesenteric white adipose tissue mainly accumulated IMI-olefin; liver mainly accumulated desnitro-IMI; pancreas predominately accumulated 4-hydroxy-IMI. The desnitro-dehydro-IMI and the desnitro-IMI metabolites recorded tissue-blood concentration ratios ≥ 1.0 for testis, brain, lung and kidney. The cumulative levels of the six detected IMI compounds (Σ6 IMI compounds) were found in the decreasing order: blood > testis > brain > kidney > lung > iWAT > gWAT > mWAT > liver > pancreas. Altogether, this study provided essential data needed for effective mechanistic elucidation of compound-specific adverse outcomes associated with chronic exposures to IMI in mammalian species.
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Affiliation(s)
- Collins Nimako
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Japan
| | - Yoshinori Ikenaka
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Japan; Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa; Translational Research Unit, Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Hokkaido University, Japan; One Health Research Center, Hokkaido University, Japan.
| | - Osei Akoto
- Chemistry Department, Kwame Nkrumah University of Science and Technology, Ghana
| | - Kazutoshi Fujioka
- Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, United States
| | - Kumiko Taira
- Department of Anesthesiology, Tokyo Women's Medical University Center east, Tokyo, Japan
| | - Koji Arizono
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Keisuke Kato
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
| | - Keisuke Takahashi
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan
| | - Shouta M M Nakayama
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Japan
| | - Takahiro Ichise
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Japan
| | - Mayumi Ishizuka
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Japan
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7
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Neurotoxic Effects of Neonicotinoids on Mammals: What Is There beyond the Activation of Nicotinic Acetylcholine Receptors?-A Systematic Review. Int J Mol Sci 2021; 22:ijms22168413. [PMID: 34445117 PMCID: PMC8395098 DOI: 10.3390/ijms22168413] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 07/29/2021] [Accepted: 08/02/2021] [Indexed: 02/07/2023] Open
Abstract
Neonicotinoids are a class of insecticides that exert their effect through a specific action on neuronal nicotinic acetylcholine receptors (nAChRs). The success of these insecticides is due to this mechanism of action, since they act as potent agonists of insect nAChRs, presenting low affinity for vertebrate nAChRs, which reduces potential toxic risk and increases safety for non-target species. However, although neonicotinoids are considered safe, their presence in the environment could increase the risk of exposure and toxicity. On the other hand, although neonicotinoids have low affinity for mammalian nAChRs, the large quantity, variety, and ubiquity of these receptors, combined with its diversity of functions, raises the question of what effects these insecticides can produce in non-target species. In the present systematic review, we investigate the available evidence on the biochemical and behavioral effects of neonicotinoids on the mammalian nervous system. In general, exposure to neonicotinoids at an early age alters the correct neuronal development, with decreases in neurogenesis and alterations in migration, and induces neuroinflammation. In adulthood, neonicotinoids induce neurobehavioral toxicity, these effects being associated with their modulating action on nAChRs, with consequent neurochemical alterations. These alterations include decreased expression of nAChRs, modifications in acetylcholinesterase activity, and significant changes in the function of the nigrostriatal dopaminergic system. All these effects can lead to the activation of a series of intracellular signaling pathways that generate oxidative stress, neuroinflammation and, finally, neuronal death. Neonicotinoid-induced changes in nAChR function could be responsible for most of the effects observed in the different studies.
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8
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Kabbani N, Olds JL. Nicotinic receptor targeting in physiological and environmental vulnerability: A whole of biosphere perspective. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 780:146642. [PMID: 34001335 DOI: 10.1016/j.scitotenv.2021.146642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
We propose a biosphere model of convergent interactions between nicotine and neonicotinoids (neonics) within a related framework of nicotinic receptor targeting agents (NrTA) across the globe. We explore how rising global trends in the use nicotine as well as neonics impacts vulnerability, within and across species, and posit that evolutionary conservation at the nicotinic acetylcholine receptor (nAChR) provides an operational strategy map for pathogens and disease. Furthermore, we examine the effects of NrTA exposure on balance within extant and developing ecological niches, food chains, and human societies. We advocate for a global strategy for biomonitoring across agriculture, wildlife, and human centers. Such a strategy would relate emergent pathogenic and infectious diseases, amongst others, along a tractable biological stress pathway. This new framework aims to better prepare society in the face of emergent pandemics through 1. identifying primary chemical drivers that can impact emergent diseases; 2. outlining data-driven strategy options for health and environmental policy decision makers.
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Affiliation(s)
- Nadine Kabbani
- School of Systems Biology, George Mason University, USA.
| | - James L Olds
- Schar School for Policy and Government, George Mason University, USA
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9
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Hirano T, Miyata Y, Kubo S, Ohno S, Onaru K, Maeda M, Kitauchi S, Nishi M, Tabuchi Y, Ikenaka Y, Ichise T, Nakayama SMM, Ishizuka M, Arizono K, Takahashi K, Kato K, Mantani Y, Yokoyama T, Hoshi N. Aging-related changes in the sensitivity of behavioral effects of the neonicotinoid pesticide clothianidin in male mice. Toxicol Lett 2021; 342:95-103. [PMID: 33609686 DOI: 10.1016/j.toxlet.2021.02.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 01/21/2021] [Accepted: 02/14/2021] [Indexed: 01/05/2023]
Abstract
Neonicotinoids, which act as agonists of the nicotinic acetylcholine receptors of insects, are widely used pesticides worldwide. Although epidemiological studies revealed that the detection amounts of neonicotinoids in urine are higher in the elderly population than other age-groups, there is no available information regarding the risks of neonicotinoids to older mammals. This study was aimed to investigate aging-related differences in the behavioral effects of the neonicotinoid pesticide clothianidin (CLO). We acutely administered a sub-NOAEL level (5 mg/kg) of CLO to adult (12-week-old) and aging (90-week-old) mice and conducted four behavioral tests focusing on the emotional behavior. In addition, we measured the concentrations of CLO and its metabolites in blood, brain and urine. There were age-related changes in most parameters in all behavioral tests, and CLO significantly decreased the locomotor activity in the open field test and elevated plus-maze test in the aging group, but not in the adult group. The concentrations of most CLO and its metabolites were significantly higher in the blood and brain and were slightly lower in the urine in the aging group compared to the adult group. These findings should contribute to our understanding of age-related differences in the adverse effects of neonicotinoids in mammals.
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Affiliation(s)
- Tetsushi Hirano
- Life Science Research Center, University of Toyama, 2630 Sugitani, Toyama, Toyama, 930-0194, Japan.
| | - Yuka Miyata
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, 657-8501, Japan
| | - Shizuka Kubo
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, 657-8501, Japan
| | - Shuji Ohno
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, 657-8501, Japan
| | - Kanoko Onaru
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, 657-8501, Japan
| | - Mizuki Maeda
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, 657-8501, Japan
| | - Sayaka Kitauchi
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, 657-8501, Japan
| | - Misaki Nishi
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, 657-8501, Japan
| | - Yoshiaki Tabuchi
- Life Science Research Center, University of Toyama, 2630 Sugitani, Toyama, Toyama, 930-0194, Japan
| | - Yoshinori Ikenaka
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan; Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Takahiro Ichise
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Shouta M M Nakayama
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Mayumi Ishizuka
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Koji Arizono
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, 3 Chome-1-100 Tsukide, Higashi Ward, Kumamoto, 862-8502, Japan
| | - Keisuke Takahashi
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba, 274-8510, Japan
| | - Keisuke Kato
- Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba, 274-8510, Japan
| | - Youhei Mantani
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, 657-8501, Japan
| | - Toshifumi Yokoyama
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, 657-8501, Japan
| | - Nobuhiko Hoshi
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, 657-8501, Japan
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10
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Rajapaksha H, Pandithavidana DR, Dahanayake JN. Demystifying Chronic Kidney Disease of Unknown Etiology (CKDu): Computational Interaction Analysis of Pesticides and Metabolites with Vital Renal Enzymes. Biomolecules 2021; 11:261. [PMID: 33578980 PMCID: PMC7916818 DOI: 10.3390/biom11020261] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/29/2021] [Accepted: 02/05/2021] [Indexed: 12/28/2022] Open
Abstract
Chronic kidney disease of unknown etiology (CKDu) has been recognized as a global non-communicable health issue. There are many proposed risk factors for CKDu and the exact reason is yet to be discovered. Understanding the inhibition or manipulation of vital renal enzymes by pesticides can play a key role in understanding the link between CKDu and pesticides. Even though it is very important to take metabolites into account when investigating the relationship between CKDu and pesticides, there is a lack of insight regarding the effects of pesticide metabolites towards CKDu. In this study, a computational approach was used to study the effects of pesticide metabolites on CKDu. Further, interactions of selected pesticides and their metabolites with renal enzymes were studied using molecular docking and molecular dynamics simulation studies. It was evident that some pesticides and metabolites have affinity to bind at the active site or at regulatory sites of considered renal enzymes. Another important discovery was the potential of some metabolites to have higher binding interactions with considered renal enzymes compared to the parent pesticides. These findings raise the question of whether pesticide metabolites may be a main risk factor towards CKDu.
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Affiliation(s)
| | | | - Jayangika N. Dahanayake
- Department of Chemistry, Faculty of Science, University of Kelaniya, Dalugama, Kelaniya 11600, Western Province, Sri Lanka; (H.R.); (D.R.P.)
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11
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Anadón A, Ares I, Martínez M, Martínez-Larrañaga MR, Martínez MA. Neurotoxicity of Neonicotinoids. ADVANCES IN NEUROTOXICOLOGY 2020. [DOI: 10.1016/bs.ant.2019.11.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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12
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Hirano T, Minagawa S, Furusawa Y, Yunoki T, Ikenaka Y, Yokoyama T, Hoshi N, Tabuchi Y. Growth and neurite stimulating effects of the neonicotinoid pesticide clothianidin on human neuroblastoma SH-SY5Y cells. Toxicol Appl Pharmacol 2019; 383:114777. [PMID: 31626844 DOI: 10.1016/j.taap.2019.114777] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 10/03/2019] [Accepted: 10/05/2019] [Indexed: 10/25/2022]
Abstract
Neonicotinoids are one of most widely used pesticides targeting nicotinic acetylcholine receptors (nAChRs) of insects. Recent epidemiological evidence revealed increasing amounts of neonicotinoids detected in human samples, raising the critical question of whether neonicotinoids affect human health. We investigated the effects of a neonicotinoid pesticide clothianidin (CTD) on human neuroblastoma SH-SY5Y cells as in vitro models of human neuronal cells. Cellular and functional effects of micromolar doses of CTD were evaluated by changes in cell growth, intracellular signaling activities and gene expression profiles. We examined further the effects of CTD on neuronal differentiation by measuring neurite outgrowth. Exposure to CTD (1-100 μM) significantly increased the number of cells within 24 h of culture. The nAChRs antagonists, mecamylamine and SR16584, inhibited this effect, suggesting human α3β4 nAChRs could be targets of neonicotinoids. We observed a transient intracellular calcium influx and increased phosphorylation of extracellular signal-regulated kinase 1/2 shortly after exposure to CTD. Transcriptome analysis revealed that CTD down-regulated genes involved in neuronal function (e.g., formation of filopodia and calcium ion influx) and morphology (e.g., axon guidance signaling and cytoskeleton signaling); these changes were reflected by a finding of increased neurite length during neuronal differentiation. These findings provide novel insight into the potential risks of neonicotinoids to the human nervous system.
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Affiliation(s)
- Tetsushi Hirano
- Life Science Research Center, University of Toyama, Toyama, Japan.
| | - Satsuki Minagawa
- Life Science Research Center, University of Toyama, Toyama, Japan
| | - Yukihiro Furusawa
- Department of Liberal Arts and Sciences, Toyama Prefectural University, Toyama, Japan
| | - Tatsuya Yunoki
- Department of Ophthalmology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Yoshinori Ikenaka
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido, Japan; Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Toshifumi Yokoyama
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Nobuhiko Hoshi
- Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Yoshiaki Tabuchi
- Life Science Research Center, University of Toyama, Toyama, Japan
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Erban T, Sopko B, Talacko P, Harant K, Kadlikova K, Halesova T, Riddellova K, Pekas A. Chronic exposure of bumblebees to neonicotinoid imidacloprid suppresses the entire mevalonate pathway and fatty acid synthesis. J Proteomics 2019; 196:69-80. [DOI: 10.1016/j.jprot.2018.12.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 12/07/2018] [Accepted: 12/20/2018] [Indexed: 11/16/2022]
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Abd-Elhakim YM, Mohammed HH, Mohamed WAM. Imidacloprid Impacts on Neurobehavioral Performance, Oxidative Stress, and Apoptotic Events in the Brain of Adolescent and Adult Rats. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:13513-13524. [PMID: 30501185 DOI: 10.1021/acs.jafc.8b05793] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Currently, imidacloprid (IMI) is the first insecticide and the second agrochemical highly applied all over the world. Here, we report on the impacts of IMI on neurobehavioral performance, oxidative stress, and apoptotic changes in the brain in either adult or adolescent rats. Forty male rats (adult and adolescent) were allocated to four groups. IMI groups were orally given 1 mg IMI/kg b.wt. dissolved in corn oil, whereas the controls were orally administered corn oil daily for 60 days. The obtained results demonstrated that IMI exposure resulted in less exploratory activity, deficit sensorimotor functions, and high depression. Levels of neurotransmitter including serotonin, gamma-aminobutyric acid, and dopamine were significantly reduced. Oxidative damage of brain tissues was evident following IMI exposure represented by the high levels of protein carbonyl, 8-hydroxyguanosine, and malondialdehyde, but total antioxidant capacity was reduced. Histopathological investigations of the brain tissues of IMI treated group revealed varying degrees of degeneration of the neuron. The immunohistochemical evaluation revealed a strong presence of glial fibrillary acidic protein (GFAP) and Bax positive cells, but a low expression of Bcl-2. These injurious impacts of IMI were very prominent in the adult rats than in the adolescent rats. Conclusively, exposure to IMI even at very low concentration could induce multiple neurobehavioral aberrations and neurotoxic impacts, especially in adults.
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Affiliation(s)
- Yasmina M Abd-Elhakim
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine , Zagazig University , Zagazig 44519 , Egypt
| | - Hesham H Mohammed
- Department of Veterinary Pubic Health, Faculty of Veterinary Medicine , Zagazig University , Zagazig 44519 , Egypt
| | - Wafaa A M Mohamed
- Department of Clinical Pathology, Faculty of Veterinary Medicine , Zagazig University , Zagazig 44519 , Egypt
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Redox imbalance caused by pesticides: a review of OPENTOX-related research. Arh Hig Rada Toksikol 2018; 69:126-134. [PMID: 29990294 DOI: 10.2478/aiht-2018-69-3105] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 05/01/2018] [Indexed: 11/20/2022] Open
Abstract
Pesticides are a highly diverse group of compounds and the most important chemical stressors in the environment. Mechanisms that could explain pesticide toxicity are constantly being studied and their interactions at the cellular level are often observed in well-controlled in vitro studies. Several pesticide groups have been found to impair the redox balance in the cell, but the mechanisms leading to oxidative stress for certain pesticides are only partly understood. As our scientific project "Organic pollutants in environment - markers and biomarkers of toxicity (OPENTOX)" is dedicated to studying toxic effects of selected insecticides and herbicides, this review is focused on reporting the knowledge regarding oxidative stress-related phenomena at the cellular level. We wanted to single out the most important facts relevant to the evaluation of our own findings from studies conducted on in vitro cell models.
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Casida JE. Neonicotinoids and Other Insect Nicotinic Receptor Competitive Modulators: Progress and Prospects. ANNUAL REVIEW OF ENTOMOLOGY 2018; 63:125-144. [PMID: 29324040 DOI: 10.1146/annurev-ento-020117-043042] [Citation(s) in RCA: 156] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Neonicotinoids (neonics) are remarkably effective as plant systemics to control sucking insects and for flea control on dogs and cats. The nitroimines imidacloprid, clothianidin, thiamethoxam, and dinotefuran are the leaders among the seven commercial neonics that also include the nitromethylene nitenpyram, the nitromethylene-derived cycloxaprid, and the cyanoimines acetamiprid and thiacloprid. Honey bees are highly sensitive to the nitroimines and nitromethylenes, but the cyanoimines are less toxic. All neonics are nicotinic acetylcholine receptor (nAChR) agonists with a common mode of action, target-site cross-resistance, and much higher potency on insect than mammalian nAChRs at defined binding sites. The structurally related sulfoximine sulfoxaflor and butenolide flupyradifurone are also nAChR agonists, and the mesoionic triflumezopyrim is a nAChR competitive modulator with little or no target-site cross-resistance. Some neonics induce stress tolerance in plants via salicylate-associated systems. The neonics in general are readily metabolized and, except for pollinators, have favorable toxicological profiles.
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Affiliation(s)
- John E Casida
- Environmental Chemistry and Toxicology Laboratory, Department of Environmental Science, Policy, and Management, University of California, Berkeley, California 94720;
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17
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Wang X, Anadón A, Wu Q, Qiao F, Ares I, Martínez-Larrañaga MR, Yuan Z, Martínez MA. Mechanism of Neonicotinoid Toxicity: Impact on Oxidative Stress and Metabolism. Annu Rev Pharmacol Toxicol 2017; 58:471-507. [PMID: 28968193 DOI: 10.1146/annurev-pharmtox-010617-052429] [Citation(s) in RCA: 168] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Thousands of tons of neonicotinoids are widely used around the world as broad-spectrum systemic insecticides and veterinary drugs. Researchers originally thought that neonicotinoids exhibited low mammalian toxicity. However, following their widespread use, it became increasingly evident that neonicotinoids could have various toxic effects on vertebrates and invertebrates. The primary focus of this review is to summarize the research progress associated with oxidative stress as a plausible mechanism for neonicotinoid-induced toxicity as well as neonicotinoid metabolism. This review summarizes the research conducted over the past decade into the production of reactive oxygen species, reactive nitrogen species, and oxidative stress as aresult of neonicotinoid treatments, along with their correlation with the toxicity and metabolism of neonicotinoids. The metabolism of neonicotinoids and protection of various compounds against neonicotinoid-induced toxicity based on their antioxidative effects is also discussed. This review sheds new light on the critical roles of oxidative stress in neonicotinoid-induced toxicity to nontarget species.
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Affiliation(s)
- Xu Wang
- Department of Toxicology and Pharmacology, Faculty of Veterinary Medicine, Universidad Complutense de Madrid, 28040 Madrid, Spain; .,National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan, Hubei 430070, China;
| | - Arturo Anadón
- Department of Toxicology and Pharmacology, Faculty of Veterinary Medicine, Universidad Complutense de Madrid, 28040 Madrid, Spain;
| | - Qinghua Wu
- College of Life Science, Yangtze University, Jingzhou 434025, China.,Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Králové, Hradec Králové 50003, Czech Republic
| | - Fang Qiao
- MAO Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | - Irma Ares
- Department of Toxicology and Pharmacology, Faculty of Veterinary Medicine, Universidad Complutense de Madrid, 28040 Madrid, Spain;
| | - María-Rosa Martínez-Larrañaga
- Department of Toxicology and Pharmacology, Faculty of Veterinary Medicine, Universidad Complutense de Madrid, 28040 Madrid, Spain;
| | - Zonghui Yuan
- National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan, Hubei 430070, China; .,MAO Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products, Huazhong Agricultural University, Wuhan, Hubei 430070, China.,Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Wuhan, Hubei 430070, China
| | - María-Aránzazu Martínez
- Department of Toxicology and Pharmacology, Faculty of Veterinary Medicine, Universidad Complutense de Madrid, 28040 Madrid, Spain;
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18
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Hirano T, Yanai S, Omotehara T, Hashimoto R, Umemura Y, Kubota N, Minami K, Nagahara D, Matsuo E, Aihara Y, Shinohara R, Furuyashiki T, Mantani Y, Yokoyama T, Kitagawa H, Hoshi N. The combined effect of clothianidin and environmental stress on the behavioral and reproductive function in male mice. J Vet Med Sci 2015; 77:1207-15. [PMID: 25960033 PMCID: PMC4638285 DOI: 10.1292/jvms.15-0188] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Neonicotinoids, some of the most widely used pesticides in the world, act as agonists to
the nicotinic acetylcholine receptors (nAChRs) of insects, resulting in death from
abnormal excitability. Neonicotinoids unexpectedly became a major topic as a compelling
cause of honeybee colony collapse disorder, which is damaging crop production that
requires pollination worldwide. Mammal nAChRs appear to have a certain affinity for
neonicotinoids with lower levels than those of insects; there is thus rising concern about
unpredictable adverse effects of neonicotinoids on vertebrates. We hypothesized that the
effects of neonicotinoids would be enhanced under a chronic stressed condition, which is
known to alter the expression of targets of neonicotinoids, i.e.,
neuronal nAChRs. We performed immunohistochemical and behavioral analyses in male mice
actively administered a neonicotinoid, clothianidin (CTD; 0, 10, 50 and 250 mg/kg/day),
for 4 weeks under an unpredictable chronic stress procedure. Vacuolated seminiferous
epithelia and a decrease in the immunoreactivity of the antioxidant enzyme glutathione
peroxidase 4 were observed in the testes of the CTD+stress mice. In an open field test,
although the locomotor activities were not affected, the anxiety-like behaviors of the
mice were elevated by both CTD and stress. The present study demonstrates that the
behavioral and reproductive effects of CTD become more serious in combination with
environmental stress, which may reflect our actual situation of multiple exposure.
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Affiliation(s)
- Tetsushi Hirano
- Laboratory of Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan
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19
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Simon-Delso N, Amaral-Rogers V, Belzunces LP, Bonmatin JM, Chagnon M, Downs C, Furlan L, Gibbons DW, Giorio C, Girolami V, Goulson D, Kreutzweiser DP, Krupke CH, Liess M, Long E, McField M, Mineau P, Mitchell EAD, Morrissey CA, Noome DA, Pisa L, Settele J, Stark JD, Tapparo A, Van Dyck H, Van Praagh J, Van der Sluijs JP, Whitehorn PR, Wiemers M. Systemic insecticides (neonicotinoids and fipronil): trends, uses, mode of action and metabolites. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:5-34. [PMID: 25233913 PMCID: PMC4284386 DOI: 10.1007/s11356-014-3470-y] [Citation(s) in RCA: 930] [Impact Index Per Article: 103.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Accepted: 08/15/2014] [Indexed: 04/15/2023]
Abstract
Since their discovery in the late 1980s, neonicotinoid pesticides have become the most widely used class of insecticides worldwide, with large-scale applications ranging from plant protection (crops, vegetables, fruits), veterinary products, and biocides to invertebrate pest control in fish farming. In this review, we address the phenyl-pyrazole fipronil together with neonicotinoids because of similarities in their toxicity, physicochemical profiles, and presence in the environment. Neonicotinoids and fipronil currently account for approximately one third of the world insecticide market; the annual world production of the archetype neonicotinoid, imidacloprid, was estimated to be ca. 20,000 tonnes active substance in 2010. There were several reasons for the initial success of neonicotinoids and fipronil: (1) there was no known pesticide resistance in target pests, mainly because of their recent development, (2) their physicochemical properties included many advantages over previous generations of insecticides (i.e., organophosphates, carbamates, pyrethroids, etc.), and (3) they shared an assumed reduced operator and consumer risk. Due to their systemic nature, they are taken up by the roots or leaves and translocated to all parts of the plant, which, in turn, makes them effectively toxic to herbivorous insects. The toxicity persists for a variable period of time-depending on the plant, its growth stage, and the amount of pesticide applied. A wide variety of applications are available, including the most common prophylactic non-Good Agricultural Practices (GAP) application by seed coating. As a result of their extensive use and physicochemical properties, these substances can be found in all environmental compartments including soil, water, and air. Neonicotinoids and fipronil operate by disrupting neural transmission in the central nervous system of invertebrates. Neonicotinoids mimic the action of neurotransmitters, while fipronil inhibits neuronal receptors. In doing so, they continuously stimulate neurons leading ultimately to death of target invertebrates. Like virtually all insecticides, they can also have lethal and sublethal impacts on non-target organisms, including insect predators and vertebrates. Furthermore, a range of synergistic effects with other stressors have been documented. Here, we review extensively their metabolic pathways, showing how they form both compound-specific and common metabolites which can themselves be toxic. These may result in prolonged toxicity. Considering their wide commercial expansion, mode of action, the systemic properties in plants, persistence and environmental fate, coupled with limited information about the toxicity profiles of these compounds and their metabolites, neonicotinoids and fipronil may entail significant risks to the environment. A global evaluation of the potential collateral effects of their use is therefore timely. The present paper and subsequent chapters in this review of the global literature explore these risks and show a growing body of evidence that persistent, low concentrations of these insecticides pose serious risks of undesirable environmental impacts.
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Affiliation(s)
- N Simon-Delso
- Environmental Sciences, Copernicus Institute, Utrecht University, Heidelberglaan 2, 3584 CS, Utrecht, The Netherlands,
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Meijer M, Dingemans MML, van den Berg M, Westerink RHS. Inhibition of voltage-gated calcium channels as common mode of action for (mixtures of) distinct classes of insecticides. Toxicol Sci 2014; 141:103-11. [PMID: 24913802 DOI: 10.1093/toxsci/kfu110] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Humans are exposed to distinct structural classes of insecticides with different neurotoxic modes of action. Because calcium homeostasis is essential for proper neuronal function and development, we investigated the effects of insecticides from different classes (pyrethroid: (α-)cypermethrin; organophosphate: chlorpyrifos; organochlorine: endosulfan; neonicotinoid: imidacloprid) and mixtures thereof on the intracellular calcium concentration ([Ca(2+)]i). Effects of acute (20 min) exposure to (mixtures of) insecticides on basal and depolarization-evoked [Ca(2+)]i were studied in vitro with Fura-2-loaded PC12 cells and high resolution single-cell fluorescence microscopy. The data demonstrate that cypermethrin, α-cypermethrin, endosulfan, and chlorpyrifos concentration-dependently decreased depolarization-evoked [Ca(2+)]i, with 50% (IC50) at 78nM, 239nM, 250nM, and 899nM, respectively. Additionally, acute exposure to chlorpyrifos or endosulfan (10μM) induced a modest increase in basal [Ca(2+)]i, amounting to 68 ± 8nM and 53 ± 8nM, respectively. Imidacloprid did not disturb basal or depolarization-evoked [Ca(2+)]i at 10μM. Following exposure to binary mixtures, effects on depolarization-evoked [Ca(2+)]i were within the expected effect additivity range, whereas the effect of the tertiary mixture was less than this expected additivity effect range. These results demonstrate that different types of insecticides inhibit depolarization-evoked [Ca(2+)]i in PC12 cells by inhibiting voltage-gated calcium channels (VGCCs) in vitro at concentrations comparable with human occupational exposure levels. Moreover, the effective concentrations in this study are below those for earlier described modes of action. Because inhibition of VGCCs appears to be a common and potentially additive mode of action of several classes of insecticides, this target should be considered in neurotoxicity risk assessment studies.
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Affiliation(s)
- Marieke Meijer
- Neurotoxicology Research Group, Toxicology Division, Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, NL-3508 TD Utrecht, The Netherlands
| | - Milou M L Dingemans
- Neurotoxicology Research Group, Toxicology Division, Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, NL-3508 TD Utrecht, The Netherlands
| | - Martin van den Berg
- Neurotoxicology Research Group, Toxicology Division, Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, NL-3508 TD Utrecht, The Netherlands
| | - Remco H S Westerink
- Neurotoxicology Research Group, Toxicology Division, Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, NL-3508 TD Utrecht, The Netherlands
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21
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Kim J, Park Y, Yoon KS, Clark JM, Park Y. Imidacloprid, a neonicotinoid insecticide, induces insulin resistance. J Toxicol Sci 2014; 38:655-60. [PMID: 24025781 DOI: 10.2131/jts.38.655] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Recently, scientific evidence supports a connection between environmental chemical exposures, which includes insecticides, and development of type 2 diabetes. However, there is limited information about the link between influences of neonicotinoid insecticides and incidence of type 2 diabetes. Thus, the purpose of the study was to determine effects of imidacloprid, a neonicotinoid insecticide, on glucose metabolism. Three different cell models were used; adipocytes (3T3-L1), hepatocytes (HepG2), and myotubes (C2C12). These cells were treated with imidacloprid (0, 10, and 20 μM) for 4-6 days followed by treatment with insulin for 15 min to determine responses. Insulin stimulated glucose uptake was reduced by imidacloprid in all three cell culture models. Treatment with imidacloprid reduced phosphorylation of protein kinase B (AKT), one of the major regulators of insulin signaling, without changing overall AKT expression. Subsequently, imidacloprid reduced phosphorylation of ribosomal S6 kinase (S6K), which is a downstream target of AKT and also a feed-back inhibitor of insulin signaling. These results suggest that imidacloprid could induce insulin resistance by affecting the insulin signaling cascade, particularly up-stream of AKT, in adipocytes, liver, and muscle.
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Affiliation(s)
- Jonggun Kim
- Department of Food Science, University of Massachusetts, USA
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Randhawa MA, Anjum MN, Butt MS, Yasin M, Imran M. Minimization of Imidacloprid Residues in Cucumber and Bell Pepper Through Washing with Citric Acid and Acetic Acid Solutions and Their Dietary Intake Assessment. INTERNATIONAL JOURNAL OF FOOD PROPERTIES 2014. [DOI: 10.1080/10942912.2012.678532] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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23
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Scientific Opinion on the developmental neurotoxicity potential of acetamiprid and imidacloprid. EFSA J 2013. [DOI: 10.2903/j.efsa.2013.3471] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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Ding T, Jacobs D, Lavine BK. Liquid chromatography-mass spectrometry identification of imidacloprid photolysis products. Microchem J 2011. [DOI: 10.1016/j.microc.2011.07.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Nie HZ, Li ZQ, Yan QX, Wang ZJ, Zhao WJ, Guo LC, Yin M. Nicotine decreases beta-amyloid through regulating BACE1 transcription in SH-EP1-α4β2 nAChR-APP695 cells. Neurochem Res 2011; 36:904-12. [PMID: 21336821 DOI: 10.1007/s11064-011-0420-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2011] [Indexed: 11/29/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder that affects the elderly population. Deposition of beta-amyloid (Aβ) in the brain is a hallmark of AD pathology. In our previous study, we have constructed a cell line expressing human APP695 (hAPP695) in SH-EP1 cells stably transfected with human nicotinic receptor (nAChR) α4 subunit and β2 subunit gene. In present study, we found that activation of α4β2 nAChR by nicotine and epibatidine decreased secreted Aβ level in the cell line and hippocampal neurons, but had no effects on full-length APP695 and sAPP-α. Nicotine also decreases BACE1 and PSEN1 expression, as well as ERK1 and NFκB P65 subunit expression in the cell line. Furthermore, BACE1 promoter activity is, but PSEN1 not, decreased by nicotine in the cell line. All the results suggest that activation of α4β2 nAChR decreases Aβ through regulating BACE1 transcription by ERK1-NFκB pathway. Additionally, analysis of BACE1 promoter activity by dual-luciferase reporter assay may be useful for drug screening as a high throughput method.
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Affiliation(s)
- Hui-Zhen Nie
- Laboratory of Neuropharmacology, School of Pharmacy, Shanghai Jiao Tong University, 200240 Shanghai, China
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26
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André JM, Leach PT, Gould TJ. Nicotine ameliorates NMDA receptor antagonist-induced deficits in contextual fear conditioning through high-affinity nicotinic acetylcholine receptors in the hippocampus. Neuropharmacology 2010; 60:617-25. [PMID: 21167848 DOI: 10.1016/j.neuropharm.2010.12.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Revised: 12/06/2010] [Accepted: 12/08/2010] [Indexed: 01/31/2023]
Abstract
NMDA glutamate receptors (NMDARs) and nicotinic acetylcholine receptors (nAChRs) are both involved in learning and synaptic plasticity. Increasing evidence suggests processes mediated by these receptors may interact to modulate learning; however, little is known about the neural substrates involved in these interactive processes. The present studies investigated the effects of nicotine on MK-801 hydrogen maleate (MK-801) and DL-2-Amino-5-phosphonovaleric acid (APV)-induced disruption of contextual fear conditioning in male C57BL/6J mice, using direct drug infusion and selective nAChR antagonists to define the brain regions and the nAChR subtypes involved. Mice treated with MK-801 showed a deficit in contextual fear conditioning that was ameliorated by nicotine. Direct drug infusion demonstrated that the NMDAR antagonists disrupted hippocampal function and that nicotine acted in the dorsal hippocampus to ameliorate the deficit in learning. The high-affinity nAChR antagonist Dihydro-β-erythroidine hydrobromide (DhβE) blocked the effects of nicotine on MK-801-induced deficits while the α7 nAChR antagonist methyllycaconitine citrate salt hydrate (MLA) did not. These results suggest that NMDARs and nAChRs may mediate similar hippocampal processes involved in contextual fear conditioning. Furthermore, these results may have implications for developing effective therapeutics for the cognitive deficits associated with schizophrenia because a large subset of patients with schizophrenia exhibit cognitive deficits that may be related to NMDAR dysfunction and smoke at much higher rates than the healthy population, which may be an attempt to ameliorate cognitive deficits.
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Affiliation(s)
- Jessica M André
- Department of Psychology, Temple University, Philadelphia, PA 19122, USA
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Chen RJ, Ho YS, Guo HR, Wang YJ. Rapid Activation of Stat3 and ERK1/2 by Nicotine Modulates Cell Proliferation in Human Bladder Cancer Cells. Toxicol Sci 2008; 104:283-93. [DOI: 10.1093/toxsci/kfn086] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Davis JA, Kenney JW, Gould TJ. Hippocampal alpha4beta2 nicotinic acetylcholine receptor involvement in the enhancing effect of acute nicotine on contextual fear conditioning. J Neurosci 2007; 27:10870-7. [PMID: 17913920 PMCID: PMC2705889 DOI: 10.1523/jneurosci.3242-07.2007] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Nicotine is known to enhance learning and memory in hippocampus-dependent tasks such as contextual fear conditioning. The present study was designed to directly examine whether the hippocampus plays a role in mediating this enhancement and which nicotinic acetylcholine receptor (nAChR) subtypes localized to the hippocampus are critical for enhanced learning. Contextual fear conditioning consisted of two white noise conditioned stimuli presentations, each coterminating with a 2 s, 0.57 mA footshock separated by a 120 s intertrial interval. Nicotine (0.09, 0.18, and 0.35 microg per side) was bilaterally infused into the dorsal hippocampus before training and testing. Infusions of nicotine into the dorsal hippocampus produced a dose-dependent enhancement of contextual fear conditioning. To determine which nAChRs are critical to the enhancing effect of nicotine, the preferential alpha4beta2 nAChR antagonist, dihydro-beta-erythroidine (DHbetaE) (6.00 and 18.00 microg per side), or the preferential alpha7 nAChR antagonist, methyllycaconitine (MLA) (13.50 and 27.00 microg per side), was bilaterally infused into the dorsal hippocampus before systemic injections of nicotine (0.09 mg/kg). DHbetaE infusions dose-dependently blocked the enhancement of contextual fear conditioning by nicotine, whereas MLA infusions yielded an intermediate effect. In addition, neither DHbetaE nor MLA had an effect on contextual fear conditioning in the absence of systemic nicotine. The present results suggest a critical role for alpha4beta2 nAChRs in the dorsal hippocampus for mediating the enhancing effect of nicotine on contextual fear conditioning.
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Affiliation(s)
- Jennifer A. Davis
- Department of Psychology, Neuroscience Program, Temple University, Philadelphia, Pennsylvania 19122
| | - Justin W. Kenney
- Department of Psychology, Neuroscience Program, Temple University, Philadelphia, Pennsylvania 19122
| | - Thomas J. Gould
- Department of Psychology, Neuroscience Program, Temple University, Philadelphia, Pennsylvania 19122
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Fang Y, Svoboda KKH. Nicotine inhibits human gingival fibroblast migration via modulation of Rac signalling pathways. J Clin Periodontol 2006; 32:1200-7. [PMID: 16268995 PMCID: PMC2862378 DOI: 10.1111/j.1600-051x.2005.00845.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
AIM Cigarette smoking is a risk factor in the development of periodontal diseases. In addition, a delayed healing process has been shown in smokers compared with non-smokers after periodontal treatment. Cell migration is a key process of wound healing and it is highly regulated by a variety of signalling pathways. The small G protein, Rac, is necessary for cell migration. Our aim was to determine if nicotine disrupted Rac and its downstream signalling proteins, p21-activated kinase 1/2 (PAK1/2), and p44/42 mitogen-activated protein kinase (MAPK) (extracellular regulated kinase 1/2). MATERIAL AND METHODS Primary human fibroblasts from healthy gingival tissues were cultured and grown to confluence. Cells were serum starved for 24 h, and then treated with nicotine (0 or 0.5 microM) prior to in vitro wounding. Cell migration was analysed in live cell assays following in vitro wounds. Rac activity, phosphorylation levels of PAK1/2, and p44/42 MAPK were assessed in cultures treated with or without nicotine after multiple wounds. RESULTS Nicotine decreased cell migration rates by 50% compared with controls. In addition, nicotine altered the activation patterns of Rac and PAK 1/2 and up-regulated p44/42 MAPK. CONCLUSION Decreased cell migration in periodontal wounds exposed to nicotine may be mediated through the Rac and PAK1/2 signalling pathways.
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Affiliation(s)
- Yiyu Fang
- Biomedical Sciences Department, Texas A&M University System, Health Science Center, Baylor College of Dentistry, Dallas, TX, USA
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Brunet JL, Badiou A, Belzunces LP. In vivo metabolic fate of [14C]-acetamiprid in six biological compartments of the honeybee, Apis mellifera L. PEST MANAGEMENT SCIENCE 2005; 61:742-8. [PMID: 15880574 DOI: 10.1002/ps.1046] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The in vivo metabolism of acetamiprid was studied in the honeybee, Apis mellifera L. The distribution of acetamiprid and its metabolites was monitored over a 72-h period in six biological compartments: head, thorax, abdomen, haemolymph, midgut and rectum. Honeybees were treated orally with 100 microg [14C]-acetamiprid kg(-1) bee, a dose which is about 1500 times lower than the median lethal dose. After 72 h, only 40% of the total radioactivity was eliminated, suggesting that acetamiprid and its metabolites tended to persist in the honeybee. Acetamiprid was rapidly distributed in all compartments and metabolized. Just after administration, radioactivity was mainly localized in the abdomen and subsequently in the rectum. After 72 h, the maximum amount of radioactivity (about 20% of the ingested dose) was detected again in the abdomen, whereas the lowest level of total radioactivity was detected in the haemolymph. Radioactivity in the head did not exceed 7.6% of total ingested radioactivity. More than 50% of acetamiprid was metabolised in less than 30 min, indicating a very short half-life for the compound. During the first hours, acetamiprid was mainly detected in nicotinic acetylcholine receptor-rich tissues: abdomen, thorax and head. Of the seven metabolites detected, the major ones were 6-choronicotinic acid and an unknown metabolite called U1, which was present mainly in the rectum, the thorax and the head. Our results indicate that the low toxicity of acetamiprid may reflect its rapid metabolism.
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Affiliation(s)
- Jean-Luc Brunet
- INRA, Laboratoire de Toxicologie Environnementale, UMR 406 INRA-UAPV Ecologie des invertébrés, Site Agroparc, 84914 Avignon Cedex 9, France.
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Abstract
The neonicotinoids, the newest major class of insecticides, have outstanding potency and systemic action for crop protection against piercing-sucking pests, and they are highly effective for flea control on cats and dogs. Their common names are acetamiprid, clothianidin, dinotefuran, imidacloprid, nitenpyram, thiacloprid, and thiamethoxam. They generally have low toxicity to mammals (acute and chronic), birds, and fish. Biotransformations involve some activation reactions but largely detoxification mechanisms. In contrast to nicotine, epibatidine, and other ammonium or iminium nicotinoids, which are mostly protonated at physiological pH, the neonicotinoids are not protonated and have an electronegative nitro or cyano pharmacophore. Agonist recognition by the nicotinic receptor involves cation-pi interaction for nicotinoids in mammals and possibly a cationic subsite for interaction with the nitro or cyano substituent of neonicotinoids in insects. The low affinity of neonicotinoids for vertebrate relative to insect nicotinic receptors is a major factor in their favorable toxicological profile.
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Affiliation(s)
- Motohiro Tomizawa
- Environmental Chemistry and Toxicology Laboratory, Department of Environmental Science, Policy and Management, University of California, Berkeley, California 94720-3112, USA.
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Williams RD, Boros LG, Kolanko CJ, Jackman SM, Eggers TR. Chromosomal aberrations in human lymphocytes exposed to the anticholinesterase pesticide isofenphos with mechanisms of leukemogenesis. Leuk Res 2004; 28:947-58. [PMID: 15234572 DOI: 10.1016/j.leukres.2003.12.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2003] [Accepted: 12/15/2003] [Indexed: 11/24/2022]
Abstract
Human lymphocytes were exposed to the leukemogenic pesticide isofenphos (IFP) to investigate its effects on chromosomal DNA and cholinergic homeostasis using cholinesterase activity as a marker. Isolated peripheral lymphocytes were administered concentrations of IFP ranging from 0.1 ng/ml to 10 microg/ml. The absence (Group 1) and presence (Group 2) of DNA repair inhibitors 4 mM hydroxyurea (HU), 40 microM cytosine arabinoside (ARA-C) and an NADPH regenerating system (NRS) (Group 3) were analyzed at 1, 6 and 24 h by single cell gel electrophoresis using the comet assay. Significant damage to DNA directly from IFP at 1 h by remarkably low concentrations was observed in Group 1, escalating in Group 2 with DNA repair inhibition, while Group 3 disruptions were highest due to the presence of the NRS P-450 microsomal fraction conducive to producing reactive IFP-oxon and N-desalkyl metabolites. The extent of DNA aberrations increased further in parallel within the groups at 6 and 24 h. Male and female chemical sensitivities were similar on average (P < 0.01). Cholinesterase activity measured in a satellite group was inhibited with 0.1 microg/ml IFP by 69, 62, and 48% at 1, 6, and 24 h, respectively, indicating gradual induction of compensatory synthesis. Restoration of cholinergic homeostasis may be exceptionally impaired at higher IFP concentrations from acetyl-CoA depletion [Leuk. Res. 25 (2001) 883]. In summary, these studies reveal that exposure to the organophosphate pesticide isofenphos induces human DNA mutation beyond endogenous repair capacity and disrupts cholinergic nuclear signaling affectively constructing the mutator phenotype of leukemogenesis.
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Affiliation(s)
- Robert D Williams
- CFE Toxicology, LLC, P.O. Box 275, Lewis Center, OH 43035-0275, USA.
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Brunet JL, Maresca M, Fantini J, Belzunces LP. Human intestinal absorption of imidacloprid with Caco-2 cells as enterocyte model. Toxicol Appl Pharmacol 2004; 194:1-9. [PMID: 14728974 DOI: 10.1016/j.taap.2003.08.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
In order to assess the risk to mammals of a chronic exposure to imidacloprid (IMI), we investigated its absorption with the human intestinal Caco-2 cell line. Measurements of transepithelial transport revealed an apparent permeability coefficient of 21.6 x 10(-6) +/- 3.2 x 10(-6) cm/s reflecting a 100% absorption. The comparison of apical to basal (A-B) and basal to apical (B-A) transports showed that the monolayer presents a basal to apical polarized transport. Studies of apical uptake demonstrated that the transport was concentration-dependent and not saturable from 5 to 200 microM. Arrhenius plot analysis revealed two apparent activation energies, Ea(4-12 degrees C) = 63.8 kJ/mol and Ea(12-37 degrees C) = 18.2 kJ/mol, suggesting two temperature-dependent processes. IMI uptake was equivalent when it was performed at pH 6.0 or 7.4. Depletion of Na+ from the transport buffer did not affect the uptake, indicating that a sodium-dependent transporter was not involved. Decrease of uptake with sodium-azide or after cell surface trypsin (Ti) treatment suggested the involvement of a trypsin-sensitive ATP-dependent transporter. Investigations on apical efflux demonstrated that initial velocities paralleled the increase of loading concentrations. A cell surface trypsin treatment did not affect the apical efflux. The lack of effect when the efflux was performed against an IMI concentration gradient suggested that an energy-dependent transporter was involved. However, the inhibition of P-glycoproteins (P-gp) and multidrug resistance-associated proteins (MRP) by taxol, vincristine, and daunorubicine had no effect on IMI intracellular accumulation suggesting the involvement of transporters distinct from classical ATP binding cassette transport (ABC-transport) systems. All results suggest that IMI is strongly absorbed in vivo by inward and outward active transporters.
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Affiliation(s)
- Jean-Luc Brunet
- Laboratoire de Toxicologie Environnementale, UMR 406 INRA-UAPV, INRA, Site Agroparc, 84914 Cedex 9, Avignon, France
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