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Konus M, Koy C, Mikkat S, Kreutzer M, Zimmermann R, Iscan M, Glocker MO. Molecular adaptations of Helicoverpa armigera midgut tissue under pyrethroid insecticide stress characterized by differential proteome analysis and enzyme activity assays. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2013; 8:152-62. [DOI: 10.1016/j.cbd.2013.04.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Revised: 04/17/2013] [Accepted: 04/18/2013] [Indexed: 12/20/2022]
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102
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Bhutia D, Rai BK, Pal J. Detection of Multiple Cytochrome P450 in Hepatic Tissue of Heteropneustes fossilis (Bloch) Exposed to Cypermethrin. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/s12595-013-0063-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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103
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An Ecofriendly and Stability-Indicating HPLC Method for Determination of Permethrin Isomers: Application to Pharmaceutical Analysis. J CHEM-NY 2013. [DOI: 10.1155/2013/697831] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A green, simple, and stability-indicating RP-HPLC method was developed for simultaneous determination of permethrin isomers in pharmaceutical preparations. The separation was based on a C18analytical column (150 × 4.6 mm, i.d., 5 μm). The mobile phase consisted of ethanol: phosphoric acid solution (pH = 3) (67 : 33, v/v). The elution was carried out at 30°C temperature with a flow rate of 1.0 mL/min. Quantitation was achieved with UV detection at 215 nm. In forced degradation studies, the drug was subjected to oxidation, hydrolysis, photolysis, and heat. The method was validated for specificity, linearity, precision, accuracy, and robustness. The applied procedure was found to be linear in permethrin concentration range of 0.5–50 μg/mL with correlation coefficients of 0.9996 for each isomer. Precision was evaluated by replicate analysis in which % relative standard deviation (RSD) values for areas were found below 2.0. The recoveries obtained (99.24%–100.72%) ensured the accuracy of the developed method. The peaks of permethrin isomers well resolved from various degradation products as well as the pharmaceutical excipients. Accordingly, the proposed validated and sustainable procedure was proved to be proper for routine analyzing and stability studies of permethrin in pharmaceutical preparations.
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104
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Wolansky MJ, Tornero-Velez R. Critical consideration of the multiplicity of experimental and organismic determinants of pyrethroid neurotoxicity: a proof of concept. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2013; 16:453-490. [PMID: 24298913 DOI: 10.1080/10937404.2013.853607] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Pyrethroids (PYR) are pesticides with high insecticidal activity that may disrupt neuronal excitability in target and nontarget species. The accumulated evidence consistently showed that this neurophysiologic action is followed by alterations in motor, sensorimotor, neuromuscular, and thermoregulatory responses. Nevertheless, there are some equivocal results regarding the potency of PYR in lab animals. The estimation of potency is an important step in pesticide chemical risk assessment. In order to identify the variables influencing neurobehavioral findings across PYR studies, evidence on experimental and organismic determinants of acute PYR-induced neurotoxicity was reviewed in rodents. A comprehensive analysis of these studies was conducted focusing on test material and dosing conditions, testing conditions, animal models, and other determinants such as testing room temperature. Variations in the severity of the neurotoxicity, under lab-controlled conditions, was explained based upon factors including influence of animal species and age, test material features such as chemical structure and stereochemistry, and dosing conditions such as vehicle, route of exposure, and dose volume. If not controlled, the interplay of these factors may lead to large variance in potency estimation. This review examined the scope of acute toxicological data required to determine the safety of pesticide products, and factors and covariates that need to be controlled in order to ensure that predictivity and precaution are balanced in a risk assessment process within a reasonable time-frame, using acute PYR-induced neurotoxicity in rodents as an exemplar.
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Affiliation(s)
- M J Wolansky
- a Laboratorio de Toxicología de Mezclas Químicas, Instituto de Investigación IQUIBICEN, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Departamento Química Biológica, Facultad de Ciencias Exactas y Naturales , Universidad de Buenos Aires, Ciudad Universitaria UBA, Ciudad Autónoma de Buenos Aires , Argentina
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105
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Burns CJ, McIntosh LJ, Mink PJ, Jurek AM, Li AA. Pesticide exposure and neurodevelopmental outcomes: review of the epidemiologic and animal studies. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2013; 16:127-283. [PMID: 23777200 PMCID: PMC3705499 DOI: 10.1080/10937404.2013.783383] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Assessment of whether pesticide exposure is associated with neurodevelopmental outcomes in children can best be addressed with a systematic review of both the human and animal peer-reviewed literature. This review analyzed epidemiologic studies testing the hypothesis that exposure to pesticides during pregnancy and/or early childhood is associated with neurodevelopmental outcomes in children. Studies that directly queried pesticide exposure (e.g., via questionnaire or interview) or measured pesticide or metabolite levels in biological specimens from study participants (e.g., blood, urine, etc.) or their immediate environment (e.g., personal air monitoring, home dust samples, etc.) were eligible for inclusion. Consistency, strength of association, and dose response were key elements of the framework utilized for evaluating epidemiologic studies. As a whole, the epidemiologic studies did not strongly implicate any particular pesticide as being causally related to adverse neurodevelopmental outcomes in infants and children. A few associations were unique for a health outcome and specific pesticide, and alternative hypotheses could not be ruled out. Our survey of the in vivo peer-reviewed published mammalian literature focused on effects of the specific active ingredient of pesticides on functional neurodevelopmental endpoints (i.e., behavior, neuropharmacology and neuropathology). In most cases, effects were noted at dose levels within the same order of magnitude or higher compared to the point of departure used for chronic risk assessments in the United States. Thus, although the published animal studies may have characterized potential neurodevelopmental outcomes using endpoints not required by guideline studies, the effects were generally observed at or above effect levels measured in repeated-dose toxicology studies submitted to the U.S. Environmental Protection Agency (EPA). Suggestions for improved exposure assessment in epidemiology studies and more effective and tiered approaches in animal testing are discussed.
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Affiliation(s)
| | | | - Pamela J. Mink
- Allina Health Center for Healthcare Research & Innovation, Minneapolis, Minnesota, USA
| | - Anne M. Jurek
- Allina Health Center for Healthcare Research & Innovation, Minneapolis, Minnesota, USA
| | - Abby A. Li
- Exponent, Inc., Menlo Park, California, USA
- Address correspondence to Abby A. Li, PhD, Attn: Rebecca Edwards, Exponent, Inc., Health Sciences Group, 149 Commonwealth Drive, Menlo Park, CA 94025-1133, USA. E-mail:
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106
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Fortin MC, Aleksunes LM, Richardson JR. Alteration of the expression of pesticide-metabolizing enzymes in pregnant mice: potential role in the increased vulnerability of the developing brain. Drug Metab Dispos 2012; 41:326-31. [PMID: 23223497 DOI: 10.1124/dmd.112.049395] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Studies on therapeutic drug disposition in humans have shown significant alterations as the result of pregnancy. However, it is not known whether pesticide metabolic capacity changes throughout pregnancy, which could affect exposure of the developing brain. We sought to determine the effect of pregnancy on the expression of hepatic enzymes involved in the metabolism of pesticides. Livers were collected from virgin and pregnant C57BL/6 mice at gestational days (GD)7, GD11, GD14, GD17, and postpartum days (PD)1, PD15, and PD30. Relative mRNA expression of several enzymes involved in the metabolism of pesticides, including hepatic cytochromes (Cyp) P450s, carboxylesterases (Ces), and paraoxonase 1 (Pon1), were assessed in mice during gestation and the postpartum period. Compared with virgin mice, alterations in the expression occurred at multiple time points, with the largest changes observed on GD14. At this time point, the expression of most of the Cyps involved in pesticide metabolism in the liver (Cyp1a2, Cyp2d22, Cyp2c37, Cyp2c50, Cyp2c54, and Cyp3a11) were downregulated by 30% or more. Expression of various Ces isoforms and Pon1 were also decreased along with Pon1 activity. These data demonstrate significant alterations in the expression of key enzymes that detoxify pesticides during pregnancy, which could alter exposure of developing animals to these chemicals.
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Affiliation(s)
- Marie C Fortin
- Environmental and Occupational Health Sciences Institute, Piscataway, NJ 08854, USA
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107
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Androutsopoulos VP, Hernandez AF, Liesivuori J, Tsatsakis AM. A mechanistic overview of health associated effects of low levels of organochlorine and organophosphorous pesticides. Toxicology 2012; 307:89-94. [PMID: 23041710 DOI: 10.1016/j.tox.2012.09.011] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 09/19/2012] [Accepted: 09/25/2012] [Indexed: 12/19/2022]
Abstract
Organochlorine and organophosphate pesticides are compounds that can be detected in human populations as a result of occupational or residential exposure. Despite their occurrence in considerably low levels in humans, their biological effects are hazardous since they interact with a plethora of enzymes, proteins, receptors and transcription factors. In this review we summarize the cell and molecular effects of organochlorine and organophosphate pesticides with respect to their toxicity, with particular emphasis on glucose and lipid metabolism, their interaction with some members of the nuclear receptor family of ligand-activated transcription factors, including the steroid and peroxisome proliferator activated receptors that changes the expression of genes involved in lipid metabolism and xenobiotic detoxification. More importantly, evidence regarding the metabolic degradation of pesticides and their accumulation in tissues is presented. Potential non-cholinergic mechanisms after long-term low-dose organophosphate exposure resulting in neurodevelopmental outcomes and neurodegeneration are also addressed. We conclude that the mechanism of pesticide-mediated toxicity is a combination of various enzyme-inhibitory, metabolic and transcriptional events acting at the cellular and molecular level.
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108
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Starr JM, Scollon EJ, Hughes MF, Ross DG, Graham SE, Crofton KM, Wolansky MJ, DeVito MJ, Tornero-Velez R. Environmentally Relevant Mixtures in Cumulative Assessments: An Acute Study of Toxicokinetics and Effects on Motor Activity in Rats Exposed to a Mixture of Pyrethroids. Toxicol Sci 2012; 130:309-18. [DOI: 10.1093/toxsci/kfs245] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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109
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Wang D, Kamijima M, Okamura A, Ito Y, Yanagiba Y, Jia XF, Naito H, Ueyama J, Nakajima T. Evidence for diazinon-mediated inhibition of cis-permethrin metabolism and its effects on reproductive toxicity in adult male mice. Reprod Toxicol 2012; 34:489-97. [PMID: 22944209 DOI: 10.1016/j.reprotox.2012.07.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Revised: 06/25/2012] [Accepted: 07/25/2012] [Indexed: 10/28/2022]
Abstract
The potential toxicity resulting from combinatorial effects of organophosphorus and pyrethroid insecticides are not completely known. We evaluated male reproductive toxicity in mice co-exposed to diazinon and cis-permethrin. Nine-week-old male Sv/129 mice were exposed to diazinon (10 μmol/kg/day) or cis-permethrin (90 μmol/kg/day) alone or in combination (100 μmol/kg/day), or vehicle (corn oil), for 6 weeks. Diazinon and the diazinon-permethrin mixture inhibited plasma and liver carboxylesterase activities. In the mixture group, urinary excretion of cis-permethrin metabolite 3-phenoxybenzoic acid decreased along with increased plasma and testicular concentrations of cis-permethrin, while excretion of diazinon metabolites, diethylphosphate and diethylthiophosphate, did not change, versus mice exposed to each chemical alone, which suggested that inhibition of carboxylesterase decreased the metabolic capacity to cis-permethrin. Though the co-exposure decreased testosterone biosynthesis, increased degenerate germ cells in seminiferous tubule and sperm morphological abnormalities versus controls more clearly than exposure to cis-permethrin alone, the expected potentiation of toxicity was not evident.
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Affiliation(s)
- Dong Wang
- Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan
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110
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Tornero-Velez R, Davis J, Scollon EJ, Starr JM, Setzer RW, Goldsmith MR, Chang DT, Xue J, Zartarian V, DeVito MJ, Hughes MF. A pharmacokinetic model of cis- and trans-permethrin disposition in rats and humans with aggregate exposure application. Toxicol Sci 2012; 130:33-47. [PMID: 22859315 DOI: 10.1093/toxsci/kfs236] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Permethrin is a broad-spectrum pyrethroid insecticide and among the most widely used insecticides in homes and crops. Managing the risks for pesticides such as permethrin depends on the ability to consider diverse exposure scenarios and their relative risks. Physiologically based pharmacokinetic models of delta methrin disposition were modified to describe permethrin kinetics in the rat and human. Unlike formulated deltamethrin which consists of a single stereoisomer, permethrin is formulated as a blend of cis- and trans-diastereomers. We assessed time courses for cis-permethrin and trans-permethrin in several tissues (brain, blood, liver, and fat) in the rat following oral administration of 1 and 10mg/kg permethrin (cis/trans: 40/60). Accurate simulation of permethrin in the rat suggests that a generic model structure is promising for modeling pyrethroids. Human in vitro data and appropriate anatomical information were used to develop a provisional model of permethrin disposition with structures for managing oral, dermal, and inhalation routes of exposure. The human permethrin model was used to evaluate dietary and residential exposures in the U.S. population as estimated by EPA's Stochastic Human Exposure and Dose Simulation model. Simulated cis- and trans-DCCA, metabolites of permethrin, were consistent with measured values in the National Health and Nutrition Examination Survey, indicating that the model holds promise for assessing population exposures and quantifying dose metrics.
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Affiliation(s)
- Rogelio Tornero-Velez
- NERL/ORD, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, USA.
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111
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112
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Wason SC, Smith TJ, Perry MJ, Levy JI. Using physiologically-based pharmacokinetic models to incorporate chemical and non-chemical stressors into cumulative risk assessment: a case study of pesticide exposures. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2012; 9:1971-83. [PMID: 22754485 PMCID: PMC3386599 DOI: 10.3390/ijerph9051971] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 04/11/2012] [Indexed: 11/16/2022]
Abstract
Cumulative risk assessment has been proposed as an approach to evaluate the health risks associated with simultaneous exposure to multiple chemical and non-chemical stressors. Physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) models can allow for the inclusion and evaluation of multiple stressors, including non-chemical stressors, but studies have not leveraged PBPK/PD models to jointly consider these disparate exposures in a cumulative risk context. In this study, we focused on exposures to organophosphate (OP) pesticides for children in urban low-income environments, where these children would be simultaneously exposed to other pesticides (including pyrethroids) and non-chemical stressors that may modify the effects of these exposures (including diet). We developed a methodological framework to evaluate chemical and non-chemical stressor impacts on OPs, utilizing an existing PBPK/PD model for chlorpyrifos. We evaluated population-specific stressors that would influence OP doses or acetylcholinesterase (AChE) inhibition, the relevant PD outcome. We incorporated the impact of simultaneous exposure to pyrethroids and dietary factors on OP dose through the compartments of metabolism and PD outcome within the PBPK model, and simulated combinations of stressors across multiple exposure ranges and potential body weights. Our analyses demonstrated that both chemical and non-chemical stressors can influence the health implications of OP exposures, with up to 5-fold variability in AChE inhibition across combinations of stressor values for a given OP dose. We demonstrate an approach for modeling OP risks in the presence of other population-specific environmental stressors, providing insight about co-exposures and variability factors that most impact OP health risks and contribute to children’s cumulative health risk from pesticides. More generally, this framework can be used to inform cumulative risk assessment for any compound impacted by chemical and non-chemical stressors through metabolism or PD outcomes.
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Affiliation(s)
- Susan C. Wason
- Department of Environmental Health, Harvard School of Public Health, 401 Park Drive West, Boston, MA 02215, USA; (T.J.S.); (M.J.P.); (J.I.L.)
- Author to whom correspondence should be addressed; ; Tel.: +1-617-384-8829; Fax: +1-617-384-8819
| | - Thomas J. Smith
- Department of Environmental Health, Harvard School of Public Health, 401 Park Drive West, Boston, MA 02215, USA; (T.J.S.); (M.J.P.); (J.I.L.)
| | - Melissa J. Perry
- Department of Environmental Health, Harvard School of Public Health, 401 Park Drive West, Boston, MA 02215, USA; (T.J.S.); (M.J.P.); (J.I.L.)
- Department of Environmental and Occupational Health, School of Public Health and Health Service, George Washington University, 2300 Eye St. NW, Washington, DC 20037, USA
| | - Jonathan I. Levy
- Department of Environmental Health, Harvard School of Public Health, 401 Park Drive West, Boston, MA 02215, USA; (T.J.S.); (M.J.P.); (J.I.L.)
- Department of Environmental Health, Boston University School of Public Health, 715 Albany St., Boston, MA 02118, USA
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113
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Ross MK, Edelmann MJ. Carboxylesterases: A Multifunctional Enzyme Involved in Pesticide and Lipid Metabolism. ACS SYMPOSIUM SERIES 2012. [DOI: 10.1021/bk-2012-1099.ch010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Matthew K. Ross
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, P.O. Box 6100, Mississippi State, Mississippi 39762
- Institute for Genomics, Biocomputing and Biotechnology, Mississippi Agricultural and Forestry Experimental Station, Mississippi State University, Mississippi State, Mississippi 39762
| | - Mariola J. Edelmann
- Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, P.O. Box 6100, Mississippi State, Mississippi 39762
- Institute for Genomics, Biocomputing and Biotechnology, Mississippi Agricultural and Forestry Experimental Station, Mississippi State University, Mississippi State, Mississippi 39762
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114
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Knaak JB, Dary CC, Zhang X, Gerlach RW, Tornero-Velez R, Chang DT, Goldsmith R, Blancato JN. Parameters for pyrethroid insecticide QSAR and PBPK/PD models for human risk assessment. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2012; 219:1-114. [PMID: 22610175 DOI: 10.1007/978-1-4614-3281-4_1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In this review we have examined the status of parameters required by pyrethroid QSAR-PBPK/PD models for assessing health risks. In lieu of the chemical,biological, biochemical, and toxicological information developed on the pyrethroids since 1968, the finding of suitable parameters for QSAR and PBPK/PD model development was a monumental task. The most useful information obtained came from rat toxicokinetic studies (i.e., absorption, distribution, and excretion), metabolism studies with 14C-cyclopropane- and alcohol-labeled pyrethroids, the use of known chiral isomers in the metabolism studies and their relation to commercial products. In this review we identify the individual chiralisomers that have been used in published studies and the chiral HPLC columns available for separating them. Chiral HPLC columns are necessary for isomer identification and for developing kinetic values (Vm,, and Kin) for pyrethroid hydroxylation. Early investigators synthesized analytical standards for key pyrethroid metabolites, and these were used to confirm the identity of urinary etabolites, by using TLC. These analytical standards no longer exist, and muste resynthesized if further studies on the kinetics of the metabolism of pyrethroids are to be undertaken.In an attempt to circumvent the availability of analytical standards, several CYP450 studies were carried out using the substrate depletion method. This approach does not provide information on the products formed downstream, and may be of limited use in developing human environmental exposure PBPK/PD models that require extensive urinary metabolite data. Hydrolytic standards (i.e., alcohols and acids) were available to investigators who studied the carboxylesterase-catalyzed hydrolysis of several pyrethroid insecticides. The data generated in these studies are suitable for use in developing human exposure PBPK/PD models.Tissue:blood partition coefficients were developed for the parent pyrethroids and their metabolites, by using a published mechanistic model introduced by Poulin and Thiele (2002a; b) and log DpH 7.4 values. The estimated coefficients, especially those of adipose tissue, were too high and had to be corrected by using a procedure in which the proportion of parent or metabolite residues that are unbound to plasma albumin is considered, as described in the GastroPlus model (Simulations Plus, Inc.,Lancaster, CA). The literature suggested that Km values be adjusted by multiplying Km by the substrate (decimal amount) that is unbound to microsomal or CYPprotein. Mirfazaelian et al. (2006) used flow- and diffusion-limited compartments in their deltamethrin model. The addition of permeability areas (PA) having diffusion limits, such as the fat and slowly perfused compartments, enabled the investigators to bring model predictions in line with in vivo data.There appears to be large differences in the manner and rate of absorption of the pyrethroids from the gastrointestinal tract, implying that GI advanced compartmental transit models (ACAT) need to be included in PBPK models. This is especially true of the absorption of an oral dose of tefluthrin in male rats, in which 3.0-6.9%,41.3-46.3%, and 5.2-15.5% of the dose is eliminated in urine, feces, and bile,respectively (0-48 h after administration). Several percutaneous studies with the pyrethroids strongly support the belief that these insecticides are not readily absorbed, but remain on the surface of the skin until they are washed off. In one articular study (Sidon et al. 1988) the high levels of permethrin absorption through the forehead skin (24-28%) of the monkey was reported over a 7- to 14-days period.Wester et al. (1994) reported an absorption of 1.9% of pyrethrin that had been applied to the forearm of human volunteers over a 7-days period.SAR models capable of predicting the binding of the pyrethroids to plasma and hepatic proteins were developed by Yamazaki and Kanaoka (2004), Saiakhov et al. (2000), Colmenarejo et al. (2001), and Colmenarejo (2003). QikProp(Schrodinger, LLC) was used to obtain Fu values for calculating partition coefficients and for calculating permeation constants (Caco-2, MDCK, and logBBB). ADMET Predictor (Simulations Plus Inc.) provided Vm~,x and Km values for the hydroxylation of drugs/pyrethroids by human liver recombinant cytochrome P450 enzymes making the values available for possible use in PBPK/PD models.The Caco-2 permeability constants and CYP3A4 Vmax and Km values are needed in PBPK/PD models with GI ACAT sub models. Modeling work by Chang et al.(2009) produced rate constants (kcat) for the hydrolysis of pyrethroids by rat serumcarboxylesterases. The skin permeation model of Potts and Guy (1992) was used topredict K, values for the dermal absorption of the 15 pyrethroids.The electrophysiological studies by Narahashi (1971) and others (Breckenridgeet al. 2009; Shafer et al. 2005; Soderlund et al. 2002; Wolansky and Harrill 2008)demonstrated that the mode of action of pyrethroids on nerves is to interfere with the changes in sodium and potassium ion currents. The pyrethroids, being highly lipid soluble, are bound or distributed in lipid bilayers of the nerve cell membrane and exert their action on sodium channel proteins. The rising phase of the action potential is caused by sodium influx (sodium activation), while the falling phase is caused by sodium activation being turned off, and an increase in potassium efflux(potassium activation). The action of allethrin and other pyrethroids is caused by an inhibition or block of the normal currents. An equation by Tatebayashi and Narahashi (1994) that describes the action of pyrethroids on sodium channels was found in the literature. This equation, or some variation of it, may be suitable for use in the PD portion of pyrethroid PBPK models.
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Affiliation(s)
- James B Knaak
- Department of Pharmacology and Toxicology, SUNY at Buffalo, Buffalo, NY 14214, USA.
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115
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Vences-Mejía A, Gómez-Garduño J, Caballero-Ortega H, Dorado-González V, Nosti-Palacios R, Labra-Ruíz N, Espinosa-Aguirre JJ. Effect of mosquito mats (pyrethroid-based) vapor inhalation on rat brain cytochrome P450s. Toxicol Mech Methods 2011; 22:41-6. [DOI: 10.3109/15376516.2011.591448] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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116
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Večeřa R, Zachařová A, Orolin J, Strojil J, Skottová N, Anzenbacher P. Fenofibrate-induced decrease of expression of CYP2C11 and CYP2C6 in rat. Biopharm Drug Dispos 2011; 32:482-7. [PMID: 21968795 DOI: 10.1002/bdd.774] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 06/17/2011] [Accepted: 08/15/2011] [Indexed: 11/10/2022]
Abstract
This short communication is aimed to investigate whether the widely used hypolipidemic drug fenofibrate affects CYP2C11 and CYP2C6 in rats, both counterparts of human CYP2C9, known to metabolise many drugs including S-warfarin and largely used non-steroidal antiinflammatory drugs such as ibuprofen, diclofenac and others. The effects of fenofibrate on the expression of rat liver CYP2C11 and CYP2C6 were studied in both healthy Wistar rats and hereditary hypertriglyceridemic rats. Both strains of rats were fed on diet containing fenofibrate (0.1% w/w) for 20 days. Fenofibrate highly significantly suppressed the expression of mRNA of CYP2C11 and less that of CYP2C6 in liver microsomes of both rat strains; this effect was associated with a corresponding decrease in protein levels. The results indicate that the combination of fenofibrate with drugs metabolised by CYP2C9 in humans should be taken with caution as it may lead, for example, to the potentiation of warfarin effects. This type of drug interaction has been observed previously and the results presented here could contribute to the explanation of their mechanism.
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Affiliation(s)
- Rostislav Večeřa
- Institute of Pharmacology, Faculty of Medicine and Dentistry, Palacký University, Hněvotínská, 3, 775 15 Olomouc, Czech Republic
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Lertkiatmongkol P, Jenwitheesuk E, Rongnoparut P. Homology modeling of mosquito cytochrome P450 enzymes involved in pyrethroid metabolism: insights into differences in substrate selectivity. BMC Res Notes 2011; 4:321. [PMID: 21892968 PMCID: PMC3228512 DOI: 10.1186/1756-0500-4-321] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Accepted: 09/06/2011] [Indexed: 11/29/2022] Open
Abstract
Background Cytochrome P450 enzymes (P450s) have been implicated in insecticide resistance. Anopheles minumus mosquito P450 isoforms CYP6AA3 and CYP6P7 are capable of metabolizing pyrethroid insecticides, however CYP6P8 lacks activity against this class of compounds. Findings Homology models of the three An. minimus P450 enzymes were constructed using the multiple template alignment method. The predicted enzyme model structures were compared and used for molecular docking with insecticides and compared with results of in vitro enzymatic assays. The three model structures comprise common P450 folds but differences in geometry of their active-site cavities and substrate access channels are prominent. The CYP6AA3 model has a large active site allowing it to accommodate multiple conformations of pyrethroids. The predicted CYP6P7 active site is more constrained and less accessible to binding of pyrethroids. Moreover the predicted hydrophobic interface in the active-site cavities of CYP6AA3 and CYP6P7 may contribute to their substrate selectivity. The absence of CYP6P8 activity toward pyrethroids appears to be due to its small substrate access channel and the presence of R114 and R216 that may prevent access of pyrethroids to the enzyme heme center. Conclusions Differences in active site topologies among CYPAA3, CYP6P7, and CYP6P8 enzymes may impact substrate binding and selectivity. Information obtained using homology models has the potential to enhance the understanding of pyrethroid metabolism and detoxification mediated by P450 enzymes.
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Affiliation(s)
- Panida Lertkiatmongkol
- Department of Biochemistry, Faculty of Science, Mahidol University, Phayatai, Bangkok 10400, Thailand.
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118
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Biomonitoring Equivalents for deltamethrin. Regul Toxicol Pharmacol 2011; 60:189-99. [DOI: 10.1016/j.yrtph.2011.03.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Accepted: 03/29/2011] [Indexed: 11/19/2022]
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119
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Takaku T, Mikata K, Matsui M, Nishioka K, Isobe N, Kaneko H. In vitro metabolism of trans-permethrin and its major metabolites, PBalc and PBacid, in humans. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:5001-5005. [PMID: 21456540 DOI: 10.1021/jf200032q] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
To estimate the metabolic profile of trans-permethrin in humans, a comparison of the in vitro metabolism of trans-permethrin in humans and rats was conducted using hepatic microsomes, and cytochrome P450 and UDP-glucuronyltransferase isoforms, which catalyze the metabolism of 3-phenoxybenzyl alcohol (PBalc) and 3-phenoxybenzoic acid (PBacid), respectively. In humans and rats, the major metabolic reaction of trans-permethrin in microsomal incubations was the cleavage of ester linkage to give PBalc, followed by oxidation to 4'-OH-PBalc, 4'-OH-PBacid, and PBacid. As to 4'-hydroxylation of PBalc, several CYPs were able to catalyze the reaction, and CYP2E1 was identified as a predominant isoform. PBacid and its conjugates (glucuronide and glycine) are major urinary metabolites of trans-permethrin in mammals. PBacid is also a metabolite of several pyrethroids, and has been used as a biomarker of human exposure to pyrethroids. Our study indicated that there was no difference in glucuronyltransferase activity of PBacid between humans and rats, and that only UGT1A9 can catalyze the glucuronidation of PBacid among human UGTs. Some UGT1A9 variants are known to have poor glucuronidation activity. From these results, it was assumed that deficiency or polymorphism of UGT1A9 might affect the profile of PBacid and its conjugates in urine collected from persons exposed to trans-permethrin or other pyrethroids. These results are helpful for understanding the metabolism of trans-permethrin in humans and determining methods for quantification of target analytes for assessment of human exposure to trans-permethrin and other pyrethroids that give PBacid and its conjugates as urinary metabolites.
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Affiliation(s)
- Tomoyuki Takaku
- Environmental Health Science Laboratory, Sumitomo Chemical, Co., Ltd. 1-98, 3-Chome, Kasugade-naka Konohana-ku, Osaka, Japan.
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120
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Hirosawa N, Ueyama J, Kondo T, Kamijima M, Takagi K, Fujinaka S, Hirate A, Hasegawa T, Wakusawa S. Effect of DDVP on urinary excretion levels of pyrethroid metabolite 3-phenoxybenzoic acid in rats. Toxicol Lett 2011; 203:28-32. [DOI: 10.1016/j.toxlet.2011.02.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Revised: 02/21/2011] [Accepted: 02/21/2011] [Indexed: 10/18/2022]
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121
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Kaneko H. Pyrethroids: mammalian metabolism and toxicity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:2786-2791. [PMID: 21133409 DOI: 10.1021/jf102567z] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Synthetic pyrethroids, a major insecticide group, are used worldwide to control agricultural and household pests. Mammalian metabolism of pyrethroids was substantially launched in the 1960s and 1970s by the research groups of Professor Casida and Sumitomo Chemical Co., which made great contributions to the elucidation of their metabolic fates. They showed that ester hydrolysis and oxidation play predominant roles in mammalian metabolism of pyrethroids and that rapid metabolism leads to low mammalian toxicity. These metabolic reactions are mediated by carboxylesterases and CYP isoforms, the resultant metabolites then undergoing various conjugation reactions. In general, there are substantially neither significant species differences in metabolic reactions of pyrethoids nor metabolic differences among their chiral isomers except with fenvalerate, one isomer of which yields a lipophilic conjugate causing toxicity.
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Affiliation(s)
- Hideo Kaneko
- Environmental Health Science Laboratory, Sumitomo Chemical Company Ltd., 1-98-3 Kasugadenaka, Konohana-ku Osaka, Japan.
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122
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Duangkaew P, Pethuan S, Kaewpa D, Boonsuepsakul S, Sarapusit S, Rongnoparut P. Characterization of mosquito CYP6P7 and CYP6AA3: differences in substrate preference and kinetic properties. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2011; 76:236-248. [PMID: 21308761 DOI: 10.1002/arch.20413] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 12/23/2010] [Accepted: 01/03/2011] [Indexed: 05/30/2023]
Abstract
Cytochrome P450 monooxygenases are involved in insecticide resistance in insects. We previously observed an increase in CYP6P7 and CYP6AA3 mRNA expression in Anopheles minimus mosquitoes during the selection for deltamethrin resistance in the laboratory. CYP6AA3 has been shown to metabolize deltamethrin, while no information is known for CYP6P7. In this study, CYP6P7 was heterologously expressed in the Spodoptera frugiperda (Sf9) insect cells via baculovirus-mediated expression system. The expressed CYP6P7 protein was used for exploitation of its enzymatic activity against insecticides after reconstitution with the An. minimus NADPH-cytochrome P450 reductase enzyme in vitro. The ability of CYP6P7 to metabolize pyrethroids and insecticides in the organophosphate and carbamate groups was compared with CYP6AA3. The results revealed that both CYP6P7 and CYP6AA3 proteins could metabolize permethrin, cypermethrin, and deltamethrin pyrethroid insecticides, but showed the absence of activity against bioallethrin (pyrethroid), chlorpyrifos (organophosphate), and propoxur (carbamate). CYP6P7 had limited capacity in metabolizing λ-cyhalothrin (pyrethroid), while CYP6AA3 displayed activity toward λ-cyhalothrin. Kinetic properties suggested that CYP6AA3 had higher efficiency in metabolizing type I than type II pyrethroids, while catalytic efficiency of CYP6P7 toward both types was not significantly different. Their kinetic parameters in insecticide metabolism and preliminary inhibition studies by test compounds in the flavonoid, furanocoumarin, and methylenedioxyphenyl groups elucidated that CYP6P7 had different enzyme properties compared with CYP6AA3. © 2011 Wiley Periodicals, Inc.
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Affiliation(s)
- Panida Duangkaew
- Department of Biochemistry, Faculty of Science, Mahidol University, Rama 6 Road, Phyatai, Bangkok, Thailand
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123
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Biotechnological synthesis of drug metabolites using human cytochrome P450 isozymes heterologously expressed in fission yeast. Bioanalysis 2011; 1:821-30. [PMID: 21083140 DOI: 10.4155/bio.09.53] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Cytochrome P450 mono-oxygenases (CYPs) are the major enzymes involved in the metabolism of drugs and poisons in humans. The variation of their activity - due to genetic polymorphisms or enzyme inhibition/induction - potentially increases the risk of side effects or toxicity. Studies on CYP-dependent metabolism are important in drug-development or toxicity studies. Reference standards of drug metabolites required for such studies, especially in the context of metabolites in safety testing (MIST), are often not commercially available and their classical chemical synthesis can be cumbersome. Recently, a biotechnological approach using human CYP isozymes heterologously expressed in fission yeast was developed for the synthesis of drug metabolites. Among other aspects, this approach has the distinct advantages that the reactions run under mild conditions and that only the final product must be isolated and characterized. This review overviews the first practical applications of this new approach and discusses the selection of substrates, metabolites and fission yeast strains as well as important aspects of incubation, product isolation and clean-up.
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124
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Shah I, Houck K, Judson RS, Kavlock RJ, Martin MT, Reif DM, Wambaugh J, Dix DJ. Using nuclear receptor activity to stratify hepatocarcinogens. PLoS One 2011; 6:e14584. [PMID: 21339822 PMCID: PMC3038857 DOI: 10.1371/journal.pone.0014584] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Accepted: 09/21/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Nuclear receptors (NR) are a superfamily of ligand-activated transcription factors that control a range of cellular processes. Persistent stimulation of some NR is a non-genotoxic mechanism of rodent liver cancer with unclear relevance to humans. Here we report on a systematic analysis of new in vitro human NR activity data on 309 environmental chemicals in relationship to their liver cancer-related chronic outcomes in rodents. RESULTS The effects of 309 environmental chemicals on human constitutive androstane receptors (CAR/NR1I3), pregnane X receptor (PXR/NR1I2), aryl hydrocarbon receptor (AhR), peroxisome proliferator-activated receptors (PPAR/NR1C), liver X receptors (LXR/NR1H), retinoic X receptors (RXR/NR2B) and steroid receptors (SR/NR3) were determined using in vitro data. Hepatic histopathology, observed in rodents after two years of chronic treatment for 171 of the 309 chemicals, was summarized by a cancer lesion progression grade. Chemicals that caused proliferative liver lesions in both rat and mouse were generally more active for the human receptors, relative to the compounds that only affected one rodent species, and these changes were significant for PPAR (p0.001), PXR (p0.01) and CAR (p0.05). Though most chemicals exhibited receptor promiscuity, multivariate analysis clustered them into relatively few NR activity combinations. The human NR activity pattern of chemicals weakly associated with the severity of rodent liver cancer lesion progression (p0.05). CONCLUSIONS The rodent carcinogens had higher in vitro potency for human NR relative to non-carcinogens. Structurally diverse chemicals with similar NR promiscuity patterns weakly associated with the severity of rodent liver cancer progression. While these results do not prove the role of NR activation in human liver cancer, they do have implications for nuclear receptor chemical biology and provide insights into putative toxicity pathways. More importantly, these findings suggest the utility of in vitro assays for stratifying environmental contaminants based on a combination of human bioactivity and rodent toxicity.
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Affiliation(s)
- Imran Shah
- National Center for Computational Toxicology, Office of Research and Development, United States Environmental Protection Agency, Research Triangle Park, North Carolina, United States of America.
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125
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Ranson H, N'guessan R, Lines J, Moiroux N, Nkuni Z, Corbel V. Pyrethroid resistance in African anopheline mosquitoes: what are the implications for malaria control? Trends Parasitol 2011; 27:91-8. [PMID: 20843745 DOI: 10.1016/j.pt.2010.08.004] [Citation(s) in RCA: 736] [Impact Index Per Article: 56.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 08/05/2010] [Accepted: 08/10/2010] [Indexed: 11/19/2022]
Affiliation(s)
- Hilary Ranson
- Vector Group, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, UK, L3 5QA
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126
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Mikata K, Isobe N, Kaneko H. Biotransformation and Enzymatic Reactions of Synthetic Pyrethroids in Mammals. Top Curr Chem (Cham) 2011; 314:113-35. [DOI: 10.1007/128_2011_254] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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127
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Sams C, Jones K. Human volunteer studies investigating the potential for toxicokinetic interactions between the pesticides deltamethrin; pirimicarb and chlorpyrifos-methyl following oral exposure at the acceptable daily intake. Toxicol Lett 2010; 200:41-5. [PMID: 21035527 DOI: 10.1016/j.toxlet.2010.10.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 10/01/2010] [Accepted: 10/21/2010] [Indexed: 11/16/2022]
Abstract
Human volunteer studies have been conducted by orally administering the pesticides deltamethrin (0.01 mg/kg/day) or pirimicarb (0.02 mg/kg/day) at the acceptable daily intake (ADI) together with chlorpyrifos-methyl (0.01 mg/kg/day), in order to investigate any potential interactions that may occur during dietary exposure. Deltamethrin and pirimicarb are metabolised in vivo by hydrolytic enzymes, which may be susceptible to inhibition by esterase-inhibiting compounds, such as chlorpyrifos-methyl. Urine samples were collected at time points up to at least 48 h post-exposure and metabolites were quantified. Urinary metabolite excretion data obtained from the mixed exposures were compared with data obtained from the same individuals given a dose of each individual pesticide on a separate occasion. Metabolite excretion profiles for both pesticides administered as a mixed dose with chlorpyrifos-methyl were qualitatively similar to those obtained for the individual doses. Peak excretion of deltamethrin and pirimicarb metabolites occurred at around 4h post-exposure for both the individual and the mixed exposure scenarios, and metabolite excretion was almost complete within 24h. No statistically significant differences were found between the individual and mixed doses for either metabolite excretion half-life or metabolite levels quantified in 24-h total urine collections. The data presented here indicate that no significant toxicokinetic interactions occur between either deltamethrin or pirimicarb and chlorpyrifos-methyl when orally administered together at the ADI.
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Affiliation(s)
- Craig Sams
- Health and Safety Laboratory, Harpur Hill, Buxton SK179JN, UK.
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128
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Nillos MG, Chajkowski S, Rimoldi JM, Gan J, Lavado R, Schlenk D. Stereoselective Biotransformation of Permethrin to Estrogenic Metabolites in Fish. Chem Res Toxicol 2010; 23:1568-75. [DOI: 10.1021/tx100167x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mae Grace Nillos
- Department of Environmental Sciences, University of California, Riverside, California 92521, Department of Chemistry, University of the Philippines, Miag-ao, Iloilo 5023, Philippines, and Department of Medicinal Chemistry, School of Pharmacy, University of Mississippi, Mississippi 38677
| | - Sarah Chajkowski
- Department of Environmental Sciences, University of California, Riverside, California 92521, Department of Chemistry, University of the Philippines, Miag-ao, Iloilo 5023, Philippines, and Department of Medicinal Chemistry, School of Pharmacy, University of Mississippi, Mississippi 38677
| | - John M. Rimoldi
- Department of Environmental Sciences, University of California, Riverside, California 92521, Department of Chemistry, University of the Philippines, Miag-ao, Iloilo 5023, Philippines, and Department of Medicinal Chemistry, School of Pharmacy, University of Mississippi, Mississippi 38677
| | - Jay Gan
- Department of Environmental Sciences, University of California, Riverside, California 92521, Department of Chemistry, University of the Philippines, Miag-ao, Iloilo 5023, Philippines, and Department of Medicinal Chemistry, School of Pharmacy, University of Mississippi, Mississippi 38677
| | - Ramon Lavado
- Department of Environmental Sciences, University of California, Riverside, California 92521, Department of Chemistry, University of the Philippines, Miag-ao, Iloilo 5023, Philippines, and Department of Medicinal Chemistry, School of Pharmacy, University of Mississippi, Mississippi 38677
| | - Daniel Schlenk
- Department of Environmental Sciences, University of California, Riverside, California 92521, Department of Chemistry, University of the Philippines, Miag-ao, Iloilo 5023, Philippines, and Department of Medicinal Chemistry, School of Pharmacy, University of Mississippi, Mississippi 38677
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129
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Metabolism of carbosulfan II. Human interindividual variability in its in vitro hepatic biotransformation and the identification of the cytochrome P450 isoforms involved. Chem Biol Interact 2010; 185:163-73. [DOI: 10.1016/j.cbi.2010.03.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Revised: 03/10/2010] [Accepted: 03/11/2010] [Indexed: 11/23/2022]
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130
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Tornero-Velez R, Mirfazaelian A, Kim KB, Anand SS, Kim HJ, Haines WT, Bruckner JV, Fisher JW. Evaluation of deltamethrin kinetics and dosimetry in the maturing rat using a PBPK model. Toxicol Appl Pharmacol 2010; 244:208-17. [DOI: 10.1016/j.taap.2009.12.034] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2009] [Revised: 12/18/2009] [Accepted: 12/22/2009] [Indexed: 01/10/2023]
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131
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Sadowska-Woda I, Popowicz D, Karowicz-Bilińska A. Bifenthrin-induced oxidative stress in human erythrocytes in vitro and protective effect of selected flavonols. Toxicol In Vitro 2010; 24:460-4. [DOI: 10.1016/j.tiv.2009.09.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Revised: 09/25/2009] [Accepted: 09/28/2009] [Indexed: 11/26/2022]
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132
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Sadowska-Woda I, Wójcik N, Karowicz-Bilińska A, Bieszczad-Bedrejczuk E. Effect of selected antioxidants in beta-cyfluthrin-induced oxidative stress in human erythrocytes in vitro. Toxicol In Vitro 2009; 24:879-84. [PMID: 19961921 DOI: 10.1016/j.tiv.2009.11.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2009] [Revised: 11/25/2009] [Accepted: 11/27/2009] [Indexed: 11/16/2022]
Abstract
beta-Cyfluthrin is one of the most widely used type II pyrethroid in agriculture. The aim of this study was to examine (1) the possibility of beta-cyfluthrin to induce oxidative stress in human erythrocytes in vitro and its effect on catalase (CAT) and superoxide dismutase (SOD) activities as well as (2) the role of melatonin (MEL; 2mM), its precursor--N-acetylserotonin (NAS; 1mM), quercetin (Q; 80 microM) and rutin (R; 80 microM) in alleviating the cytotoxic effects of beta-cyfluthrin. Erythrocytes were divided into portions. The first portion was incubated for 4h at 37 degrees C with different concentrations (0, 43, 215, 1075 ppm) of beta-cyfluthrin. The other portions were preincubated with selected antioxidant, respectively for 30 min and followed by beta-cyfluthrin incubation for 4h. Malondialdehyde (MDA) concentrations, CAT and SOD activities, as well as haemolysis percentage (H) were measured in all treatment portions of erythrocytes. It could be concluded that the in vitro toxicity of beta-cyfluthrin may be associated with oxidative stress. Significant reduction in the activities of CAT was observed at all beta-cyfluthrin concentrations, while SOD activities were significantly decreased only in erythrocytes incubated with the highest beta-cyfluthrin concentration. SOD activity of the non-pretreated erythrocytes exposed to the lowest dose of beta-cyfluthrin was significantly greater when compared to comparably beta-cyfluthrin-exposed antioxidant pretreated cells. The highest concentration of beta-cyfluthrin has caused over 35% haemolysis, and the lowest concentration about 15%. MEL pretreatment had no effect on H and MDA induction by beta-cyfluthrin. NAS, Q and R reduced H and MDA level, but could not prevent induction of these parameters. Compared to other antioxidants NAS appeared to maintain better the CAT activity at control levels for all doses of beta-cyfluthrin. Pretreatment with Q was found to protect against the decrease in SOD activity induced by beta-cyfluthrin.
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Affiliation(s)
- Izabela Sadowska-Woda
- Department of Biochemistry and Cell Biology, University of Rzeszow, ul Pigonia 6, 35-959 Rzeszow, Poland.
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Differences in hepatic expression of genes involved in lipid homeostasis between hereditary hypertriglyceridemic rats and healthy Wistar rats and in their response to dietary cholesterol. Food Chem Toxicol 2009; 47:2624-30. [DOI: 10.1016/j.fct.2009.07.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2009] [Revised: 07/15/2009] [Accepted: 07/21/2009] [Indexed: 11/22/2022]
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134
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Burger J, Fossi C, McClellan-Green P, Orlando EF. Methodologies, bioindicators, and biomarkers for assessing gender-related differences in wildlife exposed to environmental chemicals. ENVIRONMENTAL RESEARCH 2007; 50:8977-92. [PMID: 17207477 DOI: 10.1021/acs.est.6b02253] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2005] [Revised: 07/19/2006] [Accepted: 08/03/2006] [Indexed: 05/27/2023]
Abstract
Male and female organisms may have significant differences in their exposure, toxicokinetics, and response to chemicals, but gender effects have received relatively little attention, often viewed as a confounder rather than of primary importance. In this paper, we examine some of the key issues and methodologies for incorporating gender in studies of the effects of chemicals on wildlife, and explore bioindicators and biomarkers of gender effects. Examining gender-related differences in response to chemicals is complicated in wildlife because of the vast array of species, and differences in niches, lifespans, reproductive cycles and modes, and population dynamics. Further, organisms are more at risk in some ecosystems than others, which may increase the magnitude of effects. Only by studying wild animals, especially native species, can we truly understand the potential impact of gender-specific effects of chemical exposure on populations. Several factors affect gender-related differences in responses to chemicals, including exposure, age, size, seasonality, and genetic and phenotypic variation. There are clear examples where gender-related differences have had significant effects on reproductive success and population stability, including destabilization of gamete release in invertebrates, and alterations of endocrine and neuroendocrine system functioning in vertebrates. A wide range of new technologies and methods are available for examining gender-related differences in responses to chemicals. We provide examples that show that there are gender-related differences in responses to chemicals that have significant biological effects, and these gender-related differences should be taken into account by scientists, regulators, and policy makers, as well as the public.
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Affiliation(s)
- Joanna Burger
- Division of Life Sciences, Rutgers University, 604 Allison Road, Piscataway, NJ 08854P-8082, USA.
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