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Adamson A, Ilieva N, Stone WJ, De Miranda BR. Low-dose inhalation exposure to trichloroethylene induces dopaminergic neurodegeneration in rodents. Toxicol Sci 2023; 196:218-228. [PMID: 37669148 DOI: 10.1093/toxsci/kfad090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/07/2023] Open
Abstract
Trichloroethylene (TCE) is one of the most pervasive environmental contaminants in the world and is associated with Parkinson disease (PD) risk. Experimental models in rodents show that TCE is selectively toxic to dopaminergic neurons at high doses of ingestion, however, TCE is a highly volatile toxicant, and the primary pathway of human exposure is inhalation. As TCE is a highly lipophilic, volatile organic compound (VOC), inhalation exposure results in rapid diffusion throughout the brain, avoiding first-pass hepatic metabolism that necessitated high doses to recapitulate exposure conditions observed in human populations. We hypothesized that inhalation of TCE would induce significantly more potent neurodegeneration than ingestion and better recapitulate environmental conditions of vapor intrusion or off gassing from liquid TCE. To this end, we developed a novel, whole-body passive exposure inhalation chamber in which we exposed 10-month-old male and female Lewis rats to 50 ppm TCE (time weighted average, TWA) or filtered room air (control) over 8 weeks. In addition, we exposed 12-month-old male and female C57Bl/6 mice to 100 ppm TCE (TWA) or control over 12 weeks. Both rats and mice exposed to chronic TCE inhalation showed significant degeneration of nigrostriatal dopaminergic neurons as well as motor and gait impairments. TCE exposure also induced accumulation of pSer129-αSyn in dopaminergic neurons as well as microglial activation within the substantia nigra of rats. Collectively, these data indicate that TCE inhalation causes highly potent dopaminergic neurodegeneration and recapitulates some of the observed neuropathology associated with PD, providing a future platform for insight into the mechanisms and environmental conditions that influence PD risk from TCE exposure.
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Affiliation(s)
- Ashley Adamson
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, The University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
| | - Neda Ilieva
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, The University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
| | - William J Stone
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, The University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
| | - Briana R De Miranda
- Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, The University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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Adamson AB, Ilieva NM, Stone WJ, De Miranda BR. Low-dose inhalation exposure to trichloroethylene induces dopaminergic neurodegeneration in rodents. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.12.548754. [PMID: 37502893 PMCID: PMC10369984 DOI: 10.1101/2023.07.12.548754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Trichloroethylene (TCE) is one of the most pervasive environmental contaminants in the world and is associated with Parkinson disease (PD) risk. Experimental models in rodents show that TCE is selectively toxic to dopaminergic neurons at high doses of ingestion, however, TCE is a highly volatile toxicant, and the primary pathway of human exposure is inhalation. As TCE is a highly lipophilic, volatile organic contaminant (VOC), inhalation exposure results in rapid diffusion throughout the brain, avoiding first-pass hepatic metabolism that necessitated high doses to recapitulate exposure conditions observed in human populations. We hypothesized that inhalation of TCE would induce significantly more potent neurodegeneration than ingestion and better recapitulate environmental conditions of vapor intrusion or off gassing from liquid TCE. To this end, we developed a novel, whole-body passive exposure inhalation chamber in which we exposed 10-month-old male and female Lewis rats to 50 ppm TCE (time weighted average, TWA) or filtered room air (control) over 8 weeks. In addition, we exposed 12-month-old male and female C57Bl/6 mice to 100 ppm TCE (TWA) or control over 12 weeks. Both rats and mice exposed to chronic TCE inhalation showed significant degeneration of nigrostriatal dopaminergic neurons as well as motor and gait impairments. TCE exposure also induced accumulation of pSer129-αSyn in dopaminergic neurons as well as microglial activation within the substantia nigra of rats. Collectively, these data indicate that TCE inhalation causes highly potent dopaminergic neurodegeneration and recapitulates some of the observed neuropathology associated with PD, providing a future platform for insight into the mechanisms and environmental conditions that influence PD risk from TCE exposure.
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Model systems and organisms for addressing inter- and intra-species variability in risk assessment. Regul Toxicol Pharmacol 2022; 132:105197. [DOI: 10.1016/j.yrtph.2022.105197] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 05/20/2022] [Accepted: 05/25/2022] [Indexed: 12/12/2022]
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Dalaijamts C, Cichocki JA, Luo YS, Rusyn I, Chiu WA. Quantitative Characterization of Population-Wide Tissue- and Metabolite-Specific Variability in Perchloroethylene Toxicokinetics in Male Mice. Toxicol Sci 2021; 182:168-182. [PMID: 33988684 DOI: 10.1093/toxsci/kfab057] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Quantification of interindividual variability is a continuing challenge in risk assessment, particularly for compounds with complex metabolism and multi-organ toxicity. Toxicokinetic variability for perchloroethylene (perc) was previously characterized across 3 mouse strains and in 1 mouse strain with various degrees of liver steatosis. To further characterize the role of genetic variability in toxicokinetics of perc, we applied Bayesian population physiologically based pharmacokinetic (PBPK) modeling to the data on perc and metabolites in blood/plasma and tissues of male mice from 45 inbred strains from the Collaborative Cross (CC) mouse population. After identifying the most influential PBPK parameters based on global sensitivity analysis, we fit the model with a hierarchical Bayesian population analysis using Markov chain Monte Carlo simulation. We found that the data from 3 commonly used strains were not representative of the full range of variability in perc and metabolite blood/plasma and tissue concentrations across the CC population. Using interstrain variability as a surrogate for human interindividual variability, we calculated dose-dependent, chemical-, and tissue-specific toxicokinetic variability factors (TKVFs) as candidate science-based replacements for the default uncertainty factor for human toxicokinetic variability of 100.5. We found that toxicokinetic variability factors for glutathione conjugation metabolites of perc showed the greatest variability, often exceeding the default, whereas those for oxidative metabolites and perc itself were generally less than the default. Overall, we demonstrate how a combination of a population-based mouse model such as the CC with Bayesian population PBPK modeling can reduce uncertainty in human toxicokinetic variability and increase accuracy and precision in quantitative risk assessment.
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Affiliation(s)
- Chimeddulam Dalaijamts
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843-4458, USA.,Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458, USA
| | - Joseph A Cichocki
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843-4458, USA.,Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458, USA
| | - Yu-Syuan Luo
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843-4458, USA.,Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458, USA
| | - Ivan Rusyn
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843-4458, USA.,Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458, USA
| | - Weihsueh A Chiu
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843-4458, USA.,Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458, USA
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Zhang JX, Li N, Xu QY, Yang Y, Xie HB, Shen T, Zhu QX. Kupffer cell depletion attenuates IL-6/STAT3 mediates hepatocyte apoptosis in immunological liver injury of trichloroethylene sensitized mice. Int Immunopharmacol 2020; 88:106897. [PMID: 32822909 DOI: 10.1016/j.intimp.2020.106897] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/27/2020] [Accepted: 08/10/2020] [Indexed: 02/07/2023]
Abstract
Trichloroethylene (TCE) induced TCE hypersensitivity syndrome which makes immune injuries in multi-system. The multiple organ damage included skin, liver, kidney and so on. The main manifestations of liver injuries were apoptosis and edema of hepatocytes. In our previous research, we found the activation of Kupffer cells (KCs) which increased IL-6 can aggravate liver cell apoptosis in TCE sensitized mice. However, the mechanism of IL-6 in liver damages induced by TCE was not clear. This study explored the function of IL-6/STAT3 signal pathway on the TCE induced apoptosis of liver cell. We established a TCE sensitized BALB/c mouse model with a KCs inhibitor GdCl3, we found that the expressions of ALT and AST in TCE sensitization positive mice were higher than other mice, and the expressions of apoptosis-related proteins were up-regulated in TCE sensitization positive mice, GdCl3 could alleviate this process. Meanwhile, GdCl3 could significantly decrease the expressions of IL-6/STAT3 proteins. All in all, the activation of KCs can increase the expression of IL-6, IL-6R and phosphorylate STAT3, induces hepatocyte apoptosis, and participates in immunity damage of liver which induced by TCE.
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Affiliation(s)
- Jia-Xiang Zhang
- Department of Occupational Health and Environmental Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China; Institute of Dermatology, Key Laboratory of Dermatology, Ministry of Education, Hefei, Anhui, China
| | - Na Li
- Department of Occupational Health and Environmental Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China
| | - Qiong-Ying Xu
- Department of Occupational Health and Environmental Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China
| | - Yi Yang
- Department of Occupational Health and Environmental Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China
| | - Hai-Bo Xie
- Department of Occupational Health and Environmental Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China; Department of Dermatology, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Tong Shen
- Department of Occupational Health and Environmental Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China; Institute of Dermatology, Key Laboratory of Dermatology, Ministry of Education, Hefei, Anhui, China.
| | - Qi-Xing Zhu
- Institute of Dermatology, Key Laboratory of Dermatology, Ministry of Education, Hefei, Anhui, China; Department of Dermatology, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
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Yaqoob N, Bloch KM, Evans AR, Lock EA. The effect of trichloroethylene metabolites on the hepatic vitamin B12-dependent methionine salvage pathway and its relevance to increased excretion of formic acid in the rat. Toxicol Res (Camb) 2020; 9:117-126. [DOI: 10.1093/toxres/tfaa006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/31/2019] [Accepted: 02/25/2020] [Indexed: 11/13/2022] Open
Abstract
Abstract
The industrial solvent trichloroethylene (TCE) and its two major metabolites trichloroethanol (TCE-OH) and trichloroacetic acid (TCA) cause formic aciduria in male F344 rats. Prior treatment of male F344 rats with 1-aminobenzotriazole a cytochrome P450 inhibitor, followed by TCE (16mk/kg, po), completely prevented formic aciduria, but had no effect on formic acid excretion produced by TCA (8 or 16 mg/kg, po), suggesting TCA may be the proximate metabolite producing this response. Dow and Green reported an increase in the concentration of 5-methyltetrahydrofolate (5-MTHF) in the plasma of rats treated with TCE-OH, suggesting a block in the cycling of 5-MTHF to tetrahydrofolate (THF). This pathway is under the control of the vitamin B12-dependent methionine salvage pathway. We therefore treated rats with three daily doses of methylcobalamin (CH3Cbl) or hydroxocobalamin (OHCbl), a cofactor for methionine synthase, or L-methionine, followed by TCE (16 mg/kg) to determine if they could alleviate the formic aciduria. These pretreatments only partially reduced the excretion of formic acid in the urine. Although prior treatment with S-adenosyl-L-methionine had no effect on formic acid excretion. Consistent with these findings, the activity of methionine synthase in the liver of TCE-treated rats was not inhibited. Transcriptomic analysis of the liver-identified nine differential expressed genes, of note, was downregulation of Lmbrd1 involved in the conversion of vitamin B12 into CH3Cbl, a cofactor for methionine synthase. Our findings indicate that the formic aciduria produced by TCE-OH and TCA may be the result of a block in the recycling of 5-MTHF to THF, the effect on the methionine salvage pathway being a secondary response following acute exposure.
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Affiliation(s)
- Noreen Yaqoob
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK
| | - Katarzyna M Bloch
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK
| | - Andrew R Evans
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK
| | - Edward A Lock
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK
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De Miranda BR, Greenamyre JT. Trichloroethylene, a ubiquitous environmental contaminant in the risk for Parkinson's disease. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2020; 22:543-554. [PMID: 31996877 PMCID: PMC7941732 DOI: 10.1039/c9em00578a] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Organic solvents are common chemicals used in industry throughout the world, however, there is evidence for adverse health effects from exposure to these compounds. Trichloroethylene (TCE) is a halogenated solvent that has been used as a degreasing agent since the early 20th century. Due to its widespread use, TCE remains one of the most significant environmental contaminants in the US, and extensive research suggests TCE is a causative factor in a number of diseases, including cancer, fetal cardiac development, and neurotoxicity. TCE has also been implicated as a possible risk factor in the development of the most common neurodegenerative movement disorder, Parkinson's disease (PD). However, there is variable concordance across multiple occupational epidemiological studies assessing TCE (or solvent) exposure and risk for PD. In addition, there remains a degree of uncertainty about how TCE elicits toxicity to the dopaminergic system. To this end, we review the specific neurotoxic mechanisms of TCE in the context of selective vulnerability of dopaminergic neurons. In addition, we consider the complexity of combined risk factors that ultimately contribute to neurodegeneration and discuss the limitations of single-factor exposure assessments.
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Affiliation(s)
- Briana R De Miranda
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, 3501 Fifth Avenue, BST-7045, Pittsburgh, 15260, Pennsylvania, USA.
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Elkin ER, Harris SM, Su AL, Lash LH, Loch-Caruso R. Placenta as a target of trichloroethylene toxicity. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2020; 22:472-486. [PMID: 32022077 PMCID: PMC7103546 DOI: 10.1039/c9em00537d] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Trichloroethylene (TCE) is an industrial solvent and a common environmental contaminant detected in thousands of hazardous waste sites. Risk of exposure is a concern for workers in occupations that use TCE as well as for residents who live near industries that use TCE or who live near TCE-contaminated sites. Although renal, hepatic and carcinogenic effects of TCE have been documented, less is known about TCE impacts on reproductive functions despite epidemiology reports associating maternal TCE exposure with adverse pregnancy outcomes. Toxicological evidence suggests that the placenta mediates at least some of the adverse pregnancy outcomes associated with TCE exposure. Toxicology studies show that the TCE metabolite, S-(1,2-dichlorovinyl)-l-cysteine (DCVC) generates toxic effects such as mitochondrial dysfunction, apoptosis, oxidative stress, and release of prostaglandins and pro-inflammatory cytokines in placental cell lines. Each of these mechanisms of toxicity have significant implications for placental functions and, thus, ultimately the health of mother and developing child. Despite these findings there remain significant gaps in our knowledge about effects of TCE on the placenta, including effects on specific placental cell types and functions as well as sex differences in response to TCE exposure. Due to the critical role that the placenta plays in pregnancy, future research addressing some of these knowledge gaps could lead to significant gains in public health.
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Affiliation(s)
- Elana R Elkin
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI 48109-2029, USA.
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Luo YS, Cichocki JA, Hsieh NH, Lewis L, Wright FA, Threadgill DW, Chiu WA, Rusyn I. Using Collaborative Cross Mouse Population to Fill Data Gaps in Risk Assessment: A Case Study of Population-Based Analysis of Toxicokinetics and Kidney Toxicodynamics of Tetrachloroethylene. ENVIRONMENTAL HEALTH PERSPECTIVES 2019; 127:67011. [PMID: 31246107 PMCID: PMC6792382 DOI: 10.1289/ehp5105] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
BACKGROUND Interindividual variability in susceptibility remains poorly characterized for environmental chemicals such as tetrachloroethylene (PERC). Development of population-based experimental models provide a potential approach to fill this critical need in human health risk assessment. OBJECTIVES In this study, we aimed to better characterize the contribution of glutathione (GSH) conjugation to kidney toxicity of PERC and the degree of associated interindividual toxicokinetic (TK) and toxicodynamic (TD) variability by using the Collaborative Cross (CC) mouse population. METHODS Male mice from 45 strains were intragastrically dosed with PERC ([Formula: see text]) or vehicle (5% Alkamuls EL-620 in saline), and time-course samples were collected for up to 24 h. Population variability in TK of S-(1,2,2-trichlorovinyl)GSH (TCVG), S-(1,2,2-trichlorovinyl)-L-cysteine (TCVC), and N-acetyl-S-(1,2,2-trichlorovinyl)-L-cysteine (NAcTCVC) was quantified in serum, liver, and kidney, and analyzed using a toxicokinetic model. Effects of PERC on kidney weight, fatty acid metabolism-associated genes [ Acot1 (Acyl-CoA thioesterase 1), Fabp1 (fatty acid-binding protein 1), and Ehhadh (enoyl-coenzyme A, hydratase/3-hydroxyacyl coenzyme A dehydrogenase)], and a marker of proximal tubular injury [KIM-1 (kidney injury molecule-1)/Hepatitis A virus cellular receptor 1 ( Havcr1)] were evaluated. Finally, quantitative data on interstrain variability in both formation of GSH conjugation metabolites of PERC and its kidney effects was used to calculate adjustment factors for the interindividual variability in both TK and TD. RESULTS Mice treated with PERC had significantly lower kidney weight, higher kidney-to-body weight (BW) ratio, and higher expression of fatty acid metabolism-associated genes ( Acot1, Fabp1, and Ehhadh) and a marker of proximal tubular injury (KIM-1/ Havcr1). Liver levels of TCVG were significantly correlated with KIM-1/ Havcr1 in kidney, consistent with kidney injury being associated with GSH conjugation. We found that the default uncertainty factor for human variability may be marginally adequate to protect 95%, but not more, of the population for kidney toxicity mediated by PERC. DISCUSSION Overall, this study demonstrates the utility of the CC mouse population in characterizing metabolism-toxicity interactions and quantifying interindividual variability. Further refinement of the characterization of interindividual variability can be accomplished by incorporating these data into in silico population models both for TK (such as a physiologically based pharmacokinetic model), as well as for toxicodynamic responses. https://doi.org/10.1289/EHP5105.
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Affiliation(s)
- Yu-Syuan Luo
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Joseph A. Cichocki
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Nan-Hung Hsieh
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Lauren Lewis
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Fred A. Wright
- Bioinformatics Research Center and Departments of Statistics and Biological Sciences, North Carolina State University, Raleigh, North Carolina, USA
| | - David W. Threadgill
- Department of Molecular and Cellular Medicine, Texas A&M University, College Station, Texas, USA
| | - Weihsueh A. Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
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Zhang J, Li N, Yang L, Xie H, Yang Y, Wang H, Wu C, Shen T, Zhu Q. Bradykinin contributes to immune liver injury via B2R receptor-mediated pathways in trichloroethylene sensitized mice: A role in Kupffer cell activation. Toxicology 2019; 415:37-48. [PMID: 30685357 DOI: 10.1016/j.tox.2019.01.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 12/18/2018] [Accepted: 01/23/2019] [Indexed: 01/20/2023]
Abstract
We have previously shown trichloroethylene (TCE) induced occupational medicamentosa-like dermatitis due to TCE (OMLDT) with immune liver injury, and kallikrein-kinin system (KKS) activation as a probably mechanism underlying the immune damage. Bradykinin (BK) is an important active component of KKS system function, but the specific role of BK in the immune liver injury has never been examined. The present study aimed to explore the important role of BK and mechanisms of action in immune liver injury induced by TCE. TCE sensitization significantly increased the expression of BK receptor (B2R) in the liver. Compared to blank and vehicle control group, TCE sensitization positive mice developed exacerbated liver injury evidenced by elevated AST, ALT levels and hepatocyte damage. TCE sensitization also stimulated MAPK and STAT3 activation in liver tissue. B2R antagonist HOE140 ameliorated these changes. Kupffer cells (KCs) of the liver were also activated following TCE sensitization; both CD68+ KCs and CD16/CD32+ M1 type KCs were increased in TCE positive group. Further experiments isolated the KCs from the liver in each group and showed that TCE sensitization resulted activation of MAPK signal pathway which in turn caused release of the pro-inflammatory cytokines, IL-1β, IL-6, TNF-α, in KCs; the antagonist HOE140 again decreased these changes in KCs. These results uncover a novel role of BK and B2R cross-talk in KCs activation in TCE sensitized mice, mediated by pro-inflammatory cytokine release via MAPK and STAT3 activation, contributing to the immune liver injury.
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Affiliation(s)
- Jiaxiang Zhang
- Institute of Dermatology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China; Department of Occupational Health and Environment Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China
| | - Na Li
- Department of Occupational Health and Environment Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China
| | - Ling Yang
- Institute of Dermatology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Haibo Xie
- Department of Occupational Health and Environment Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China
| | - Yi Yang
- Department of Occupational Health and Environment Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China
| | - Hui Wang
- Department of Nutrition, Chaohu Hospital of Anhui Medical University, Hefei, Anhui, China
| | - Changhao Wu
- School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Tong Shen
- Department of Occupational Health and Environment Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China.
| | - Qixing Zhu
- Institute of Dermatology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China.
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Luo YS, Hsieh NH, Soldatow VY, Chiu WA, Rusyn I. Comparative analysis of metabolism of trichloroethylene and tetrachloroethylene among mouse tissues and strains. Toxicology 2018; 409:33-43. [PMID: 30053492 PMCID: PMC6186498 DOI: 10.1016/j.tox.2018.07.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 07/22/2018] [Accepted: 07/23/2018] [Indexed: 11/21/2022]
Abstract
Trichloroethylene (TCE) and tetrachloroethylene (PCE) are structurally similar chemicals that are metabolized through oxidation and glutathione conjugation pathways. Both chemicals have been shown to elicit liver and kidney toxicity in rodents and humans; however, TCE has been studied much more extensively in terms of both metabolism and toxicity. Despite their qualitative similarities, quantitative comparison of tissue- and strain-specific metabolism of TCE and PCE has not been performed. To fill this gap, we conducted a comparative toxicokinetic study where equimolar single oral doses of TCE (800 mg/kg) or PCE (1000 mg/kg) were administered to male mice of C57BL/6J, B6C3F1/J, and NZW/LacJ strains. Samples of liver, kidney, serum, brain, and lung were obtained for up to 36 h after dosing. For each tissue, concentrations of parent compounds, as well as their oxidative and glutathione conjugation metabolites were measured and concentration-time profiles constructed. A multi-compartment toxicokinetic model was developed to quantitatively compare TCE and PCE metabolism. As expected, the flux through oxidation metabolism pathway predominated over that through conjugation across all mouse strains examined, it is 1,200-3,800 fold higher for TCE and 26-34 fold higher for PCE. However, the flux through glutathione conjugation, albeit a minor metabolic pathway, was 21-fold higher for PCE as compared to TCE. The degree of inter-strain variability was greatest for oxidative metabolites in TCE-treated and for glutathione conjugation metabolites in PCE-treated mice. This study provides critical data for quantitative comparisons of TCE and PCE metabolism, and may explain the differences in organ-specific toxicity between these structurally similar chemicals.
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Affiliation(s)
- Yu-Syuan Luo
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Nan-Hung Hsieh
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Valerie Y Soldatow
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC, USA
| | - Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA.
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Dalaijamts C, Cichocki JA, Luo YS, Rusyn I, Chiu WA. Incorporation of the glutathione conjugation pathway in an updated physiologically-based pharmacokinetic model for perchloroethylene in mice. Toxicol Appl Pharmacol 2018; 352:142-152. [PMID: 29857080 PMCID: PMC6051410 DOI: 10.1016/j.taap.2018.05.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 05/16/2018] [Accepted: 05/25/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Perchloroethylene (perc) induced target organ toxicity has been associated with tissue-specific metabolic pathways. Previous physiologically-based pharmacokinetic (PBPK) modeling of perc accurately predicted oxidative metabolites but suggested the need to better characterize glutathione (GSH) conjugation as well as toxicokinetic uncertainty and variability. OBJECTIVES We updated the previously published "harmonized" perc PBPK model in mice to better characterize GSH conjugation metabolism as well as the uncertainty and variability of perc toxicokinetics. METHODS The updated PBPK model includes expanded models for perc and its oxidative metabolite trichloroacetic acid (TCA), and physiologically-based sub-models for conjugative metabolites. Previously compiled mouse kinetic data in B6C3F1 and Swiss-Webster mice were augmented to include data from a recent study in male C57BL/6J mice that measured perc and metabolites in serum and multiple tissues. Hierarchical Bayesian population analysis using Markov chain Monte Carlo was conducted to characterize uncertainty and inter-strain variability in perc metabolism. RESULTS The updated model fit the data as well or better than the previously published "harmonized" PBPK model. Tissue dosimetry for both oxidative and conjugative metabolites was successfully predicted across the three strains of mice, with estimated residuals errors of 2-fold for majority of data. Inter-strain variability across three strains was evident for oxidative metabolism; GSH conjugation data were only available for one strain. CONCLUSIONS This updated PBPK model fills a critical data gap in quantitative risk assessment by predicting the internal dosimetry of perc and its oxidative and GSH conjugation metabolites and lays the groundwork for future studies to better characterize toxicokinetic variability.
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Affiliation(s)
- Chimeddulam Dalaijamts
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Joseph A Cichocki
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Yu-Syuan Luo
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA.
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13
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Mosedale M. Mouse Population-Based Approaches to Investigate Adverse Drug Reactions. Drug Metab Dispos 2018; 46:1787-1795. [DOI: 10.1124/dmd.118.082834] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 07/06/2018] [Indexed: 01/19/2023] Open
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14
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Venkatratnam A, Furuya S, Kosyk O, Gold A, Bodnar W, Konganti K, Threadgill DW, Gillespie KM, Aylor DL, Wright FA, Chiu WA, Rusyn I. Editor's Highlight: Collaborative Cross Mouse Population Enables Refinements to Characterization of the Variability in Toxicokinetics of Trichloroethylene and Provides Genetic Evidence for the Role of PPAR Pathway in Its Oxidative Metabolism. Toxicol Sci 2018; 158:48-62. [PMID: 28369613 DOI: 10.1093/toxsci/kfx065] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Background Trichloroethylene (TCE) is a known carcinogen in humans and rodents. Previous studies of inter-strain variability in TCE metabolism were conducted in multi-strain panels of classical inbred mice with limited genetic diversity to identify gene-environment interactions associated with chemical exposure. Objectives To evaluate inter-strain variability in TCE metabolism and identify genetic determinants that are associated with TCE metabolism and effects using Collaborative Cross (CC), a large panel of genetically diverse strains of mice. Methods We administered a single oral dose of 0, 24, 80, 240, or 800 mg/kg of TCE to mice from 50 CC strains, and collected organs 24 h post-dosing. Levels of trichloroacetic acid (TCA), a major oxidative metabolite of TCE were measured in multiple tissues. Protein expression and activity levels of TCE-metabolizing enzymes were evaluated in the liver. Liver transcript levels of known genes perturbed by TCE exposure were also quantified. Genetic association mapping was performed on the acquired phenotypes. Results TCA levels varied in a dose- and strain-dependent manner in liver, kidney, and serum. The variability in TCA levels among strains did not correlate with expression or activity of a number of enzymes known to be involved in TCE oxidation. Peroxisome proliferator-activated receptor alpha (PPARα)-responsive genes were found to be associated with strain-specific differences in TCE metabolism. Conclusions This study shows that CC mouse population is a valuable tool to quantitatively evaluate inter-individual variability in chemical metabolism and to identify genes and pathways that may underpin population differences.
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Affiliation(s)
- Abhishek Venkatratnam
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843.,Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Shinji Furuya
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843
| | - Oksana Kosyk
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Avram Gold
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Wanda Bodnar
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Kranti Konganti
- Department of Molecular and Cellular Medicine, Texas A&M University, College Station, Texas 77843
| | - David W Threadgill
- Department of Molecular and Cellular Medicine, Texas A&M University, College Station, Texas 77843
| | - Kevin M Gillespie
- Bioinformatics Research Center and Departments of Statistics and Biological Sciences, North Carolina State University, Raleigh, North Carolina 27695
| | - David L Aylor
- Bioinformatics Research Center and Departments of Statistics and Biological Sciences, North Carolina State University, Raleigh, North Carolina 27695
| | - Fred A Wright
- Bioinformatics Research Center and Departments of Statistics and Biological Sciences, North Carolina State University, Raleigh, North Carolina 27695
| | - Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843
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15
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Leveraging human genetic and adverse outcome pathway (AOP) data to inform susceptibility in human health risk assessment. Mamm Genome 2018; 29:190-204. [DOI: 10.1007/s00335-018-9738-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 01/31/2018] [Indexed: 12/19/2022]
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16
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Dornbos P, LaPres JJ. Incorporating population-level genetic variability within laboratory models in toxicology: From the individual to the population. Toxicology 2018; 395:1-8. [PMID: 29275117 PMCID: PMC5801153 DOI: 10.1016/j.tox.2017.12.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 11/22/2017] [Accepted: 12/18/2017] [Indexed: 12/20/2022]
Abstract
Humans respond to chemical exposures differently due to many factors, such as previous and concurrent stressors, age, sex, and genetic background. The vast majority of laboratory-based toxicology studies, however, have not considered the impact of population-level variability within dose-response relationships. The lack of data dealing with the influence of genetic diversity on the response to chemical exposure provides a difficult challenge for risk assessment as individuals within the population will display a wide-range of responses following toxicant challenge. Notably, the genetic background of individuals plays a major role in the variability seen in a population-level response to a drug or chemical and, thus, there is growing interest in including genetic diversity into laboratory-models. Here we outline several laboratory-based models that can be used to assay the influence of genetic variability on an individual's response to chemicals: 1) genetically-diverse cell lines, 2) human primary cells, 3) and genetically-diverse mouse panels. We also provide a succinct review for several seminal studies to highlight the capability, feasibility, and power of each of these models. This article is intended to highlight the need to include population-level genetic diversity into toxicological study designs via laboratory-based models with the goal to provide and supplement evidence in assessing the risk posed by chemicals to the human population. As such, incorporation of genetic variability will positively impact human-based risk assessment and provide empirical data to aid and influence decision-making processes in relation to chemical exposures.
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Affiliation(s)
- Peter Dornbos
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
| | - John J LaPres
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, USA; Center for Mitochondrial Science and Medicine, Michigan State University, East Lansing, MI, USA.
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17
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Chiu WA, Rusyn I. Advancing chemical risk assessment decision-making with population variability data: challenges and opportunities. Mamm Genome 2018; 29:182-189. [PMID: 29299621 PMCID: PMC5849521 DOI: 10.1007/s00335-017-9731-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/27/2017] [Indexed: 02/06/2023]
Abstract
Characterizing population variability, including identifying susceptible populations and quantifying their increased susceptibility, is an important aspect of chemical risk assessment, but one that is challenging with traditional experimental models and risk assessment methods. New models and methods to address population variability can be used to advance the human health assessments of chemicals in three key areas. First, with respect to hazard identification, evaluating toxicity using population-based in vitro and in vivo models can potentially reduce both false positive and false negative signals. Second, with respect to evaluating mechanisms of toxicity, enhanced ability to do genetic mapping using these models allows for the identification of key biological pathways and mechanisms that may be involved in toxicity and/or susceptibility. Third, with respect to dose-response assessment, population-based toxicity data can serve as a surrogate for human variability, and thus be used to quantitatively estimate the degree of human toxicokinetic/toxicodynamic variability and thereby increase confidence in setting health-protective exposure limits. A number of case studies have been published that demonstrate the potential opportunities for improving risk assessment and decision-making, and include studies using Collaborative Cross and Diversity Outbred mice, as well as populations of human cell lines from the 1000 Genomes project. Key challenges include the need to apply more sophisticated computational and statistical models analyzing population-based toxicity data, and the need to integrate these more complex analyses into risk assessments and decision-making.
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Affiliation(s)
- Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77843, USA.
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77843, USA
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18
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Israel JW, Chappell GA, Simon JM, Pott S, Safi A, Lewis L, Cotney P, Boulos HS, Bodnar W, Lieb JD, Crawford GE, Furey TS, Rusyn I. Tissue- and strain-specific effects of a genotoxic carcinogen 1,3-butadiene on chromatin and transcription. Mamm Genome 2018; 29:153-167. [PMID: 29429127 PMCID: PMC6095468 DOI: 10.1007/s00335-018-9739-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 02/03/2018] [Indexed: 12/27/2022]
Abstract
Epigenetic effects of environmental chemicals are under intense investigation to fill existing knowledge gaps between environmental/occupational exposures and adverse health outcomes. Chromatin accessibility is one prominent mechanism of epigenetic control of transcription, and understanding of the chemical effects on both could inform the causal role of epigenetic alterations in disease mechanisms. In this study, we hypothesized that baseline variability in chromatin organization and transcription profiles among various tissues and mouse strains influence the outcome of exposure to the DNA damaging chemical 1,3-butadiene. To test this hypothesis, we evaluated DNA damage along with comprehensive quantification of RNA transcripts (RNA-seq), identification of accessible chromatin (ATAC-seq), and characterization of regions with histone modifications associated with active transcription (ChIP-seq for acetylation at histone 3 lysine 27, H3K27ac). We collected these data in the lung, liver, and kidney of mice from two genetically divergent strains, C57BL/6J and CAST/EiJ, that were exposed to clean air or to 1,3-butadiene (~600 ppm) for 2 weeks. We found that tissue effects dominate differences in both gene expression and chromatin states, followed by strain effects. At baseline, xenobiotic metabolism was consistently more active in CAST/EiJ, while immune system pathways were more active in C57BL/6J across tissues. Surprisingly, even though all three tissues in both strains harbored butadiene-induced DNA damage, little transcriptional effect of butadiene was observed in liver and kidney. Toxicologically relevant effects of butadiene in the lung were on the pathways of xenobiotic metabolism and inflammation. We also found that variability in chromatin accessibility across individuals (i.e., strains) only partially explains the variability in transcription. This study showed that variation in the basal states of epigenome and transcriptome may be useful indicators for individuals or tissues susceptible to genotoxic environmental chemicals.
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Affiliation(s)
- Jennifer W Israel
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA
| | - Grace A Chappell
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC, USA
| | - Jeremy M Simon
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA
| | - Sebastian Pott
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | - Alexias Safi
- Department of Pediatrics, Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Lauren Lewis
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
| | - Paul Cotney
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA
| | - Hala S Boulos
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | - Wanda Bodnar
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC, USA
| | - Jason D Lieb
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | - Gregory E Crawford
- Department of Pediatrics, Duke Center for Genomic and Computational Biology, Duke University, Durham, NC, USA
| | - Terrence S Furey
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA.
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA.
- UNC Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC, USA.
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA.
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19
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Venkatratnam A, House JS, Konganti K, McKenney C, Threadgill DW, Chiu WA, Aylor DL, Wright FA, Rusyn I. Population-based dose-response analysis of liver transcriptional response to trichloroethylene in mouse. Mamm Genome 2018; 29:168-181. [PMID: 29353386 DOI: 10.1007/s00335-018-9734-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 01/17/2018] [Indexed: 12/23/2022]
Abstract
Studies of gene expression are common in toxicology and provide important clues to mechanistic understanding of adverse effects of chemicals. Most prior studies have been performed in a single strain or cell line; however, gene expression is heavily influenced by the genetic background, and these genotype-expression differences may be key drivers of inter-individual variation in response to chemical toxicity. In this study, we hypothesized that the genetically diverse Collaborative Cross mouse population can be used to gain insight and suggest mechanistic hypotheses for the dose- and genetic background-dependent effects of chemical exposure. This hypothesis was tested using a model liver toxicant trichloroethylene (TCE). Liver transcriptional responses to TCE exposure were evaluated 24 h after dosing. Transcriptomic dose-responses were examined for both TCE and its major oxidative metabolite trichloroacetic acid (TCA). As expected, peroxisome- and fatty acid metabolism-related pathways were among the most dose-responsive enriched pathways in all strains. However, nearly half of the TCE-induced liver transcriptional perturbation was strain-dependent, with abundant evidence of strain/dose interaction, including in the peroxisomal signaling-associated pathways. These effects were highly concordant between the administered TCE dose and liver levels of TCA. Dose-response analysis of gene expression at the pathway level yielded points of departure similar to those derived from the traditional toxicology studies for both non-cancer and cancer effects. Mapping of expression-genotype-dose relationships revealed some significant associations; however, the effects of TCE on gene expression in liver appear to be highly polygenic traits that are challenging to positionally map. This study highlights the usefulness of mouse population-based studies in assessing inter-individual variation in toxicological responses, but cautions that genetic mapping may be challenging because of the complexity in gene exposure-dose relationships.
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Affiliation(s)
- Abhishek Venkatratnam
- Department of Veterinary Integrative Biosciences, Texas A&M University, 4458 TAMU, College Station, Texas, 77843, USA.,Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, North Carolina, 27599, USA
| | - John S House
- Bioinformatics Research Center, North Carolina State University, Raleigh, North Carolina, 27695, USA.,Center for Human Health and the Environment, North Carolina State University, Raleigh, North Carolina, 27695, USA
| | - Kranti Konganti
- Department of Veterinary Integrative Biosciences, Texas A&M University, 4458 TAMU, College Station, Texas, 77843, USA
| | - Connor McKenney
- NCSU Undergraduate program in Genetics, North Carolina State University, Raleigh, North Carolina, 27695, USA
| | - David W Threadgill
- Department of Veterinary Integrative Biosciences, Texas A&M University, 4458 TAMU, College Station, Texas, 77843, USA
| | - Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, 4458 TAMU, College Station, Texas, 77843, USA
| | - David L Aylor
- Bioinformatics Research Center, North Carolina State University, Raleigh, North Carolina, 27695, USA.,Center for Human Health and the Environment, North Carolina State University, Raleigh, North Carolina, 27695, USA.,Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, 27695, USA
| | - Fred A Wright
- Bioinformatics Research Center, North Carolina State University, Raleigh, North Carolina, 27695, USA.,Center for Human Health and the Environment, North Carolina State University, Raleigh, North Carolina, 27695, USA.,Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, 27695, USA.,Department of Statistics, North Carolina State University, Raleigh, North Carolina, 27695, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, 4458 TAMU, College Station, Texas, 77843, USA.
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20
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Luo YS, Furuya S, Chiu W, Rusyn I. Characterization of inter-tissue and inter-strain variability of TCE glutathione conjugation metabolites DCVG, DCVC, and NAcDCVC in the mouse. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2017; 81:37-52. [PMID: 29190187 PMCID: PMC6088749 DOI: 10.1080/15287394.2017.1408512] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/20/2017] [Indexed: 05/24/2023]
Abstract
Trichloroethylene (TCE) is a ubiquitous environmental toxicant that is a liver and kidney carcinogen. Conjugation of TCE with glutathione (GSH) leads to formation of nepthrotoxic and mutagenic metabolites postulated to be critical for kidney cancerdevelopment; however, relatively little is known regarding their tissue levels as previous analytical methods for their detection lacked sensitivity. Here, an LC-MS/MS-based method for simultaneous detection of S-(1,2-dichlorovinyl)-glutathione (DCVG), S-(1,2-dichlorovinyl)-L-cysteine (DCVC), and N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine (NAcDCVC) in multiple mouse tissues was developed. This analytical method is rapid, sensitive (limits of detection (LOD) 3-30 fmol across metabolites and tissues), and robust to quantify all three metabolites in liver, kidneys, and serum. The method was used to characterize inter-tissue and inter-strain variability in formation of conjugative metabolites of TCE. Single oral dose of TCE (24, 240 or 800 mg/kg) was administered to male mice from 20 inbred strains of Collaborative Cross. Inter-strain variability in the levels of DCVG, DCVC, and NAcDCVC (GSD = 1.6-2.9) was observed. Whereas NAcDCVC was distributed equally among analyzed tissues, highest levels of DCVG were detected in liver and DCVC in kidneys. Evidence indicated that inter-strain variability in conjugative metabolite formation of TCE might affect susceptibility to adverse health effects and that this method might aid in filling data gaps in human health assessment of TCE.
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Affiliation(s)
| | | | | | - Ivan Rusyn
- Corresponding author: Ivan Rusyn, Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843; ; (979)-458-9866
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21
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Lewis L, Crawford GE, Furey TS, Rusyn I. Genetic and epigenetic determinants of inter-individual variability in responses to toxicants. CURRENT OPINION IN TOXICOLOGY 2017; 6:50-59. [PMID: 29276797 PMCID: PMC5739339 DOI: 10.1016/j.cotox.2017.08.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
It is well established that genetic variability has a major impact on susceptibility to common diseases, responses to drugs and toxicants, and influences disease-related outcomes. The appreciation that epigenetic marks also vary across the population is growing with more data becoming available from studies in humans and model organisms. In addition, the links between genetic variability, toxicity outcomes and epigenetics are being actively explored. Recent studies demonstrate that gene-by-environment interactions involve both chromatin states and transcriptional regulation, and that epigenetics provides important mechanistic clues to connect expression-related quantitative trait loci (QTL) and disease outcomes. However, studies of Gene×Environment×Epigenetics further extend the complexity of the experimental designs and create a challenge for selecting the most informative epigenetic readouts that can be feasibly performed to interrogate multiple individuals, exposures, tissue types and toxicity phenotypes. We propose that among the many possible epigenetic experimental methodologies, assessment of chromatin accessibility coupled with total RNA levels provides a cost-effective and comprehensive option to sufficiently characterize the complexity of epigenetic and regulatory activity in the context of understanding the inter-individual variability in responses to toxicants.
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Affiliation(s)
- Lauren Lewis
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas
| | - Gregory E. Crawford
- Center for Genomic and Computational Biology and Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, NC, USA
| | - Terrence S. Furey
- Department of Genetics, Department of Biology, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas
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22
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Harrill AH, McAllister KA. New Rodent Population Models May Inform Human Health Risk Assessment and Identification of Genetic Susceptibility to Environmental Exposures. ENVIRONMENTAL HEALTH PERSPECTIVES 2017; 125:086002. [PMID: 28886592 PMCID: PMC5783628 DOI: 10.1289/ehp1274] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 04/19/2017] [Accepted: 04/27/2017] [Indexed: 05/13/2023]
Abstract
BACKGROUND This paper provides an introduction for environmental health scientists to emerging population-based rodent resources. Mouse reference populations provide an opportunity to model environmental exposures and gene-environment interactions in human disease and to inform human health risk assessment. OBJECTIVES This review will describe several mouse populations for toxicity assessment, including older models such as the Mouse Diversity Panel (MDP), and newer models that include the Collaborative Cross (CC) and Diversity Outbred (DO) models. METHODS This review will outline the features of the MDP, CC, and DO mouse models and will discuss published case studies investigating the use of these mouse population resources in each step of the risk assessment paradigm. DISCUSSION These unique resources have the potential to be powerful tools for generating hypotheses related to gene-environment interplay in human disease, performing controlled exposure studies to understand the differential responses in humans for susceptibility or resistance to environmental exposures, and identifying gene variants that influence sensitivity to toxicity and disease states. CONCLUSIONS These new resources offer substantial advances to classical toxicity testing paradigms by including genetically sensitive individuals that may inform toxicity risks for sensitive subpopulations. Both in vivo and complementary in vitro resources provide platforms with which to reduce uncertainty by providing population-level data around biological variability. https://doi.org/10.1289/EHP1274.
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Affiliation(s)
- Alison H Harrill
- Biomolecular Screening Branch, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services , Research Triangle Park, North Carolina, USA
| | - Kimberly A McAllister
- Genes, Environment, and Health Branch, Division of Extramural Research and Training, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services , Research Triangle Park, North Carolina, USA
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23
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Luo YS, Cichocki JA, McDonald TJ, Rusyn I. Simultaneous detection of the tetrachloroethylene metabolites S-(1,2,2-trichlorovinyl) glutathione, S-(1,2,2-trichlorovinyl)-L-cysteine, and N-acetyl-S-(1,2,2-trichlorovinyl)-L-cysteine in multiple mouse tissues via ultra-high performance liquid chromatography electrospray ionization tandem mass spectrometry. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2017; 80:513-524. [PMID: 28696834 PMCID: PMC5749336 DOI: 10.1080/15287394.2017.1330585] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Tetrachloroethylene (perchloroethylene; PERC) is a high-production volume chemical and ubiquitous environmental contaminant that is hazardous to human health. Toxicity attributed to PERC is mediated through oxidative and glutathione (GSH) conjugation metabolites. The conjugation of PERC by glutathione-s-transferase to generate S-(1,2,2-trichlorovinyl) glutathione (TCVG), which is subsequently metabolized to form S-(1,2,2-trichlorovinyl)-L-cysteine (TCVC) is of special importance to human health. Specifically, TCVC may be metabolized to N-acetyl-S-(1,2,2-trichlorovinyl)-L-cysteine (NAcTCVC) which is excreted through urine, or to electrophilic metabolites that are nephrotoxic and mutagenic. Little is known regarding toxicokinetics of TCVG, TCVC, and NAcTCVC as analytical methods for simultaneous determination of these metabolites in tissues have not yet been reported. Hence, an ultra-high-performance liquid chromatography electrospray ionization tandem mass spectrometry-based method was developed for analysis of TCVG, TCVC, and NAcTCVC in liver, kidneys, serum, and urine. The method is rapid, sensitive, robust, and selective for detection all three analytes in every tissue examined, with limits of detection (LOD) ranging from 1.8 to 68.2 femtomoles on column, depending on the analyte and tissue matrix. This method was applied to quantify levels of TCVG, TCVC, and NAcTCVC in tissues from mice treated with PERC (10 to 1000 mg/kg, orally) with limits of quantitation (LOQ) of 1-2.5 pmol/g in liver, 1-10 pmol/g in kidney, 1-2.5 pmol/ml in serum, and 2.5-5 pmol/ml in urine. This method is useful for further characterization of the GSH conjugative pathway of PERC in vivo and improved understanding of PERC toxicity.
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Affiliation(s)
- Yu-Syuan Luo
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Joseph A. Cichocki
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Thomas J. McDonald
- Department of Environmental and Occupational Health, Texas A&M University, College Station, TX, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
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24
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Cichocki JA, Furuya S, Venkatratnam A, McDonald TJ, Knap AH, Wade T, Sweet S, Chiu WA, Threadgill DW, Rusyn I. Characterization of Variability in Toxicokinetics and Toxicodynamics of Tetrachloroethylene Using the Collaborative Cross Mouse Population. ENVIRONMENTAL HEALTH PERSPECTIVES 2017; 125:057006. [PMID: 28572074 PMCID: PMC5726344 DOI: 10.1289/ehp788] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/26/2016] [Accepted: 10/25/2016] [Indexed: 05/27/2023]
Abstract
BACKGROUND Evaluation of interindividual variability is a challenging step in risk assessment. For most environmental pollutants, including perchloroethylene (PERC), experimental data are lacking, resulting in default assumptions being used to account for variability in toxicokinetics and toxicodynamics. OBJECTIVE We quantitatively examined the relationship between PERC toxicokinetics and toxicodynamics at the population level to test whether individuals with increased oxidative metabolism are be more sensitive to hepatotoxicity following PERC exposure. METHODS Male mice from 45 strains of the Collaborative Cross (CC) were orally administered a single dose of PERC (1,000 mg/kg) or vehicle (Alkamuls-EL620) and euthanized at various time points (n = 1/strain/time). Concentration–time profiles were generated for PERC and its primary oxidative metabolite trichloroacetate (TCA) in multiple tissues. Toxicodynamic phenotyping was also performed. RESULTS Significant variability among strains was observed in toxicokinetics of PERC and TCA in every tissue examined. Based on area under the curve (AUC), the range of liver TCA levels spanned nearly an order of magnitude (~8-fold). Expression of liver cytochrome P4502E1 did not correlate with TCA levels. Toxicodynamic phenotyping revealed an effect of PERC on bodyweight loss, induction of peroxisome proliferator activated receptor-alpha (PPARα)-regulated genes, and dysregulation of hepatic lipid homeostasis. Clustering was observed among a) liver levels of PERC, TCA, and triglycerides; b) TCA levels in liver and kidney; and c) TCA levels in serum, brain, fat, and lung. CONCLUSIONS Using the CC mouse population model, we have demonstrated a complex and highly variable relationship between PERC and TCA toxicokinetics and toxicodynamics at the population level. https://doi.org/10.1289/EHP788.
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Affiliation(s)
| | | | | | | | | | - Terry Wade
- Geochemical and Environmental Research Group
| | | | | | - David W Threadgill
- Department of Molecular and Cellular Medicine, Texas A&M University , College Station, Texas, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences
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Safe S, Li X. Endocrine disruption: Relevance of experimental studies in female animals to human studies. CURRENT OPINION IN TOXICOLOGY 2017. [DOI: 10.1016/j.cotox.2017.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lock EA, Keane P, Rowe PH, Foster JR, Antoine D, Morris CM. Trichloroethylene-induced formic aciduria in the male C57 Bl/6 mouse. Toxicology 2017; 378:76-85. [DOI: 10.1016/j.tox.2017.01.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 12/08/2016] [Accepted: 01/03/2017] [Indexed: 11/26/2022]
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Ledda C, Loreto C, Zammit C, Marconi A, Fago L, Matera S, Costanzo V, Sanzà GF, Palmucci S, Ferrante M, Costa C, Fenga C, Biondi A, Pomara C, Rapisarda V. Non‑infective occupational risk factors for hepatocellular carcinoma: A review (Review). Mol Med Rep 2017; 15:511-533. [PMID: 28000892 PMCID: PMC5364850 DOI: 10.3892/mmr.2016.6046] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 07/01/2016] [Indexed: 02/07/2023] Open
Abstract
Liver cancer is the second leading worldwide cause of cancer‑associated mortalities. Hepatocellular carcinoma, which accounts for the majority of liver tumors, ranks fifth among types of human cancer. Well‑established risk factors for liver cancer include the hepatitis B and C viruses, aflatoxins, alcohol consumption, and oral contraceptives. Tobacco smoking, androgenic steroids, and diabetes mellitus are suspected risk factors. Current knowledge regarding non‑infective occupational risk factors for liver cancer is inconclusive. The relevance of liver disorders to occupational medicine lies in the fact that the majority of chemicals are metabolized in the liver, and toxic metabolites generated via metabolism are the predominant cause of liver damage. However, their non‑specific clinical manifestations that are similar in a number of liver diseases make diagnosis difficult. Furthermore, concomitant conditions, such as viral hepatitis and alcohol or drug abuse, may mask liver disorders that result from occupational hepatotoxic agents and block the demonstration of an occupational cause. The identification of environmental agents that result in human cancer is a long and often difficult process. The purpose of the present review is to summarize current knowledge regarding the association of non‑infective occupational risk exposure and HCC, to encourage further research and draw attention to this global occupational public health problem.
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Affiliation(s)
- Caterina Ledda
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
- Hygiene and Public Health, Department of Medical Sciences, Surgical and Advanced Technologies ‘GF Ingrassia’, University of Catania, I-95123 Catania, Italy
| | - Carla Loreto
- Human Anatomy and Histology, Department of Biomedical and Biotechnology Sciences, University of Catania, I-95123 Catania, Italy
| | - Christian Zammit
- Anatomy Department, Faculty of Medicine and Surgery, University of Malta, MSD-2080 Msida, Malta
| | - Andrea Marconi
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
| | - Lucrezia Fago
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
| | - Serena Matera
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
| | - Valentina Costanzo
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
| | - Giovanni Fuccio Sanzà
- Division of Radiology, ‘Policlinico-Vittorio Emanuele’ University Hospital, University of Catania, I-95123 Catania, Italy
| | - Stefano Palmucci
- Division of Radiology, ‘Policlinico-Vittorio Emanuele’ University Hospital, University of Catania, I-95123 Catania, Italy
| | - Margherita Ferrante
- Hygiene and Public Health, Department of Medical Sciences, Surgical and Advanced Technologies ‘GF Ingrassia’, University of Catania, I-95123 Catania, Italy
| | - Chiara Costa
- Occupational Medicine, Department of the Environment, Safety, Territory, Food and Health Sciences, University of Messina, I-98125 Messina, Italy
| | - Concettina Fenga
- Occupational Medicine, Department of the Environment, Safety, Territory, Food and Health Sciences, University of Messina, I-98125 Messina, Italy
| | - Antonio Biondi
- General Surgery, Department of General Surgery and Medical-Surgical Specialties, University of Catania, I-95123 Catania, Italy
| | - Cristoforo Pomara
- Anatomy Department, Faculty of Medicine and Surgery, University of Malta, MSD-2080 Msida, Malta
- Forensic Pathology, Department of Clinical and Experimental Medicine, University of Foggia, I-71122 Foggia, Italy
| | - Venerando Rapisarda
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
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Cichocki JA, Guyton KZ, Guha N, Chiu WA, Rusyn I, Lash LH. Target Organ Metabolism, Toxicity, and Mechanisms of Trichloroethylene and Perchloroethylene: Key Similarities, Differences, and Data Gaps. J Pharmacol Exp Ther 2016; 359:110-23. [PMID: 27511820 PMCID: PMC5034707 DOI: 10.1124/jpet.116.232629] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 08/09/2016] [Indexed: 01/18/2023] Open
Abstract
Trichloroethylene (TCE) and perchloroethylene or tetrachloroethylene (PCE) are high-production volume chemicals with numerous industrial applications. As a consequence of their widespread use, these chemicals are ubiquitous environmental contaminants to which the general population is commonly exposed. It is widely assumed that TCE and PCE are toxicologically similar; both are simple olefins with three (TCE) or four (PCE) chlorines. Nonetheless, despite decades of research on the adverse health effects of TCE or PCE, few studies have directly compared these two toxicants. Although the metabolic pathways are qualitatively similar, quantitative differences in the flux and yield of metabolites exist. Recent human health assessments have uncovered some overlap in target organs that are affected by exposure to TCE or PCE, and divergent species- and sex-specificity with regard to cancer and noncancer hazards. The objective of this minireview is to highlight key similarities, differences, and data gaps in target organ metabolism and mechanism of toxicity. The main anticipated outcome of this review is to encourage research to 1) directly compare the responses to TCE and PCE using more sensitive biochemical techniques and robust statistical comparisons; 2) more closely examine interindividual variability in the relationship between toxicokinetics and toxicodynamics for TCE and PCE; 3) elucidate the effect of coexposure to these two toxicants; and 4) explore new mechanisms for target organ toxicity associated with TCE and/or PCE exposure.
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Affiliation(s)
- Joseph A Cichocki
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas (J.A.C., W.A.C., I.R.); International Agency for Research on Cancer, Lyon, France (K.Z.G., N.G.); Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan (L.H.L.)
| | - Kathryn Z Guyton
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas (J.A.C., W.A.C., I.R.); International Agency for Research on Cancer, Lyon, France (K.Z.G., N.G.); Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan (L.H.L.)
| | - Neela Guha
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas (J.A.C., W.A.C., I.R.); International Agency for Research on Cancer, Lyon, France (K.Z.G., N.G.); Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan (L.H.L.)
| | - Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas (J.A.C., W.A.C., I.R.); International Agency for Research on Cancer, Lyon, France (K.Z.G., N.G.); Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan (L.H.L.)
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas (J.A.C., W.A.C., I.R.); International Agency for Research on Cancer, Lyon, France (K.Z.G., N.G.); Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan (L.H.L.)
| | - Lawrence H Lash
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas (J.A.C., W.A.C., I.R.); International Agency for Research on Cancer, Lyon, France (K.Z.G., N.G.); Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan (L.H.L.)
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Planchart A, Mattingly CJ, Allen D, Ceger P, Casey W, Hinton D, Kanungo J, Kullman SW, Tal T, Bondesson M, Burgess SM, Sullivan C, Kim C, Behl M, Padilla S, Reif DM, Tanguay RL, Hamm J. Advancing toxicology research using in vivo high throughput toxicology with small fish models. ALTEX 2016; 33:435-452. [PMID: 27328013 PMCID: PMC5270630 DOI: 10.14573/altex.1601281] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Accepted: 05/31/2016] [Indexed: 12/18/2022]
Abstract
Small freshwater fish models, especially zebrafish, offer advantages over traditional rodent models, including low maintenance and husbandry costs, high fecundity, genetic diversity, physiology similar to that of traditional biomedical models, and reduced animal welfare concerns. The Collaborative Workshop on Aquatic Models and 21st Century Toxicology was held at North Carolina State University on May 5-6, 2014, in Raleigh, North Carolina, USA. Participants discussed the ways in which small fish are being used as models to screen toxicants and understand mechanisms of toxicity. Workshop participants agreed that the lack of standardized protocols is an impediment to broader acceptance of these models, whereas development of standardized protocols, validation, and subsequent regulatory acceptance would facilitate greater usage. Given the advantages and increasing application of small fish models, there was widespread interest in follow-up workshops to review and discuss developments in their use. In this article, we summarize the recommendations formulated by workshop participants to enhance the utility of small fish species in toxicology studies, as well as many of the advances in the field of toxicology that resulted from using small fish species, including advances in developmental toxicology, cardiovascular toxicology, neurotoxicology, and immunotoxicology. We alsoreview many emerging issues that will benefit from using small fish species, especially zebrafish, and new technologies that will enable using these organisms to yield results unprecedented in their information content to better understand how toxicants affect development and health.
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Affiliation(s)
- Antonio Planchart
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
- Center for Human Health and the Environment, North Carolina State University, Raleigh, NC, USA
| | - Carolyn J. Mattingly
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
- Center for Human Health and the Environment, North Carolina State University, Raleigh, NC, USA
| | - David Allen
- Integrated Laboratory Systems, Inc., Research Triangle Park, NC, USA
| | - Patricia Ceger
- Integrated Laboratory Systems, Inc., Research Triangle Park, NC, USA
| | - Warren Casey
- National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - David Hinton
- Nicholas School of the Environment, Duke University, Durham, NC, USA
| | - Jyotshna Kanungo
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR, USA
| | - Seth W. Kullman
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
- Center for Human Health and the Environment, North Carolina State University, Raleigh, NC, USA
| | - Tamara Tal
- Integrated Systems Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Maria Bondesson
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston, Houston, TX, USA
| | | | - Con Sullivan
- Department of Molecular & Biomedical Sciences, University of Maine, Orono, ME, USA
- Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME, USA
| | - Carol Kim
- Department of Molecular & Biomedical Sciences, University of Maine, Orono, ME, USA
- Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME, USA
| | - Mamta Behl
- Division of National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Stephanie Padilla
- Integrated Systems Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - David M. Reif
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
- Center for Human Health and the Environment, North Carolina State University, Raleigh, NC, USA
| | - Robert L. Tanguay
- Department of Environmental & Molecular Toxicology, Oregon State University, Corvallis, OR, USA
| | - Jon Hamm
- Integrated Laboratory Systems, Inc., Research Triangle Park, NC, USA
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Rapisarda V, Loreto C, Malaguarnera M, Ardiri A, Proiti M, Rigano G, Frazzetto E, Ruggeri MI, Malaguarnera G, Bertino N, Malaguarnera M, Catania VE, Di Carlo I, Toro A, Bertino E, Mangano D, Bertino G. Hepatocellular carcinoma and the risk of occupational exposure. World J Hepatol 2016; 8:573-90. [PMID: 27168870 PMCID: PMC4858622 DOI: 10.4254/wjh.v8.i13.573] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 04/01/2016] [Accepted: 04/14/2016] [Indexed: 02/06/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is the most common type of liver cancer. The main risk factors for HCC are alcoholism, hepatitis B virus, hepatitis C virus, nonalcoholic steatohepatitis, obesity, type 2 diabetes, cirrhosis, aflatoxin, hemochromatosis, Wilson's disease and hemophilia. Occupational exposure to chemicals is another risk factor for HCC. Often the relationship between occupational risk and HCC is unclear and the reports are fragmented and inconsistent. This review aims to summarize the current knowledge regarding the association of infective and non-infective occupational risk exposure and HCC in order to encourage further research and draw attention to this global occupational public health problem.
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Affiliation(s)
- Venerando Rapisarda
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Carla Loreto
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Michele Malaguarnera
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Annalisa Ardiri
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Maria Proiti
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Giuseppe Rigano
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Evelise Frazzetto
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Maria Irene Ruggeri
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Giulia Malaguarnera
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Nicoletta Bertino
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Mariano Malaguarnera
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Vito Emanuele Catania
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Isidoro Di Carlo
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Adriana Toro
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Emanuele Bertino
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Dario Mangano
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
| | - Gaetano Bertino
- Venerando Rapisarda, Dario Mangano, Occupational Medi-cine Unit, Department of Clinical and Experimental Medicine, University of Catania, 95123 Catania, Italy
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Scoville DK, White CC, Botta D, McConnachie LA, Zadworny ME, Schmuck SC, Hu X, Gao X, Yu J, Dills RL, Sheppard L, Delaney MA, Griffith WC, Beyer RP, Zangar RC, Pounds JG, Faustman EM, Kavanagh TJ. Susceptibility to quantum dot induced lung inflammation differs widely among the Collaborative Cross founder mouse strains. Toxicol Appl Pharmacol 2015; 289:240-50. [PMID: 26476918 DOI: 10.1016/j.taap.2015.09.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 08/24/2015] [Accepted: 09/24/2015] [Indexed: 10/22/2022]
Abstract
Quantum dots (QDs) are engineered semiconductor nanoparticles with unique physicochemical properties that make them potentially useful in clinical, research and industrial settings. However, a growing body of evidence indicates that like other engineered nanomaterials, QDs have the potential to be respiratory hazards, especially in the context of the manufacture of QDs and products containing them, as well as exposures to consumers using these products. The overall goal of this study was to investigate the role of mouse strain in determining susceptibility to QD-induced pulmonary inflammation and toxicity. Male mice from 8 genetically diverse inbred strains (the Collaborative Cross founder strains) were exposed to CdSe-ZnS core-shell QDs stabilized with an amphiphilic polymer. QD treatment resulted in significant increases in the percentage of neutrophils and levels of cytokines present in bronchoalveolar lavage fluid (BALF) obtained from NOD/ShiLtJ and NZO/HlLtJ mice relative to their saline (Sal) treated controls. Cadmium measurements in lung tissue indicated strain-dependent differences in disposition of QDs in the lung. Total glutathione levels in lung tissue were significantly correlated with percent neutrophils in BALF as well as with lung tissue Cd levels. Our findings indicate that QD-induced acute lung inflammation is mouse strain dependent, that it is heritable, and that the choice of mouse strain is an important consideration in planning QD toxicity studies. These data also suggest that formal genetic analyses using additional strains or recombinant inbred strains from these mice could be useful for discovering potential QD-induced inflammation susceptibility loci.
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Affiliation(s)
- David K Scoville
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Collin C White
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Dianne Botta
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Lisa A McConnachie
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Megan E Zadworny
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Stefanie C Schmuck
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Xiaoge Hu
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Xiaohu Gao
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Jianbo Yu
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Russell L Dills
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Lianne Sheppard
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA; Department of Biostatistics, University of Washington, Seattle, WA 98195, USA
| | - Martha A Delaney
- Department of Comparative Medicine, University of Washington, Seattle, WA 98195, USA; Department of Pathology, University of Washington, Seattle, WA 98195, USA
| | - William C Griffith
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Richard P Beyer
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Richard C Zangar
- Systems Toxicology Group - Division of Biological Sciences, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Joel G Pounds
- Systems Toxicology Group - Division of Biological Sciences, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Elaine M Faustman
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA
| | - Terrance J Kavanagh
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA.
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Boldenow E, Hassan I, Chames MC, Xi C, Loch-Caruso R. The trichloroethylene metabolite S-(1,2-dichlorovinyl)-l-cysteine but not trichloroacetate inhibits pathogen-stimulated TNF-α in human extraplacental membranes in vitro. Reprod Toxicol 2015; 52:1-6. [PMID: 25653212 DOI: 10.1016/j.reprotox.2015.01.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 12/20/2014] [Accepted: 01/22/2015] [Indexed: 11/29/2022]
Abstract
Extraplacental membranes define the gestational compartment and provide a barrier to infectious microorganisms ascending the gravid female reproductive tract. We tested the hypothesis that bioactive metabolites of trichloroethylene (TCE) decrease pathogen-stimulated innate immune response of extraplacental membranes. Extraplacental membranes were cultured for 4, 8, and 24h with the TCE metabolites trichloroacetate (TCA) or S-(1,2-dichlorovinyl)-l-cysteine (DCVC) in the absence or presence of lipoteichoic acid (LTA) or lipopolysaccharide (LPS) to simulate infection. In addition, membranes were cocultured with DCVC and Group B Streptococcus (GBS). DCVC (5-50μM) significantly inhibited LTA-, LPS-, and GBS-stimulated cytokine release from tissue cultures as early as 4h (P≤0.05). In contrast, TCA (up to 500μM) did not inhibit LTA-stimulated cytokine release from tissue punches. Because cytokines are important mediators for host response to infectious microorganisms these findings suggest that TCE exposure could potentially modify susceptibility to infection during pregnancy.
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Affiliation(s)
- Erica Boldenow
- Department of Environmental Health Sciences, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029, USA.
| | - Iman Hassan
- Department of Environmental Health Sciences, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029, USA.
| | - Mark C Chames
- Departments of Pathology and of Obstetrics and Gynecology, Medical School, University of Michigan, 4215 Med Sci I SPC 5602, Ann Arbor, MI 48109-5602, USA.
| | - Chuanwu Xi
- Department of Environmental Health Sciences, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029, USA.
| | - Rita Loch-Caruso
- Department of Environmental Health Sciences, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029, USA.
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Yoo HS, Bradford BU, Kosyk O, Uehara T, Shymonyak S, Collins LB, Bodnar WM, Ball LM, Gold A, Rusyn I. Comparative analysis of the relationship between trichloroethylene metabolism and tissue-specific toxicity among inbred mouse strains: kidney effects. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2015; 78:32-49. [PMID: 25424545 PMCID: PMC4281933 DOI: 10.1080/15287394.2015.958418] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Trichloroethylene (TCE) is a well-known environmental and occupational toxicant that is classified as carcinogenic to humans based on the epidemiological evidence of an association with higher risk of renal-cell carcinoma. A number of scientific issues critical for assessing human health risks from TCE remain unresolved, such as the amount of kidney-toxic glutathione conjugation metabolites formed, interspecies and interindividual differences, and the mode of action for kidney carcinogenicity. It was postulated that TCE renal metabolite levels are associated with kidney-specific toxicity. Oral dosing with TCE was conducted in subacute (600 mg/kg/d; 5 d; 7 inbred mouse strains) and subchronic (100 or 400 mg/kg/d; 1, 2, or 4 wk; 2 inbred mouse strains) designs. The quantitative relationship was evaluated between strain-, dose, and time-dependent formation of TCE metabolites from cytochrome P-450-mediated oxidation (trichloroacetic acid [TCA], dichloroacetic acid [DCA], and trichloroethanol) and glutathione conjugation [S-(1,2-dichlorovinyl)-L-cysteine and S-(1,2-dichlorovinyl)glutathione], and various kidney toxicity phenotypes. In subacute study, interstrain differences in renal TCE metabolite levels were observed. In addition, data showed that in several strains kidney-specific effects of TCE included induction of peroxisome proliferator-marker genes Cyp4a10 and Acox1, increased cell proliferation, and expression of KIM-1, a marker of tubular damage and regeneration. In subchronic study, peroxisome proliferator-marker gene induction and renal toxicity diminished while cell proliferative response was elevated in a dose-dependent manner in NZW/LacJ but not C57BL/6J mice. Overall, data demonstrated that renal TCE metabolite levels are associated with kidney-specific toxicity and that these effects are strain dependent.
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Affiliation(s)
- Hong Sik Yoo
- a Department of Environmental Sciences and Engineering , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina , USA
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Yoo HS, Bradford BU, Kosyk O, Shymonyak S, Uehara T, Collins LB, Bodnar WM, Ball LM, Gold A, Rusyn I. Comparative analysis of the relationship between trichloroethylene metabolism and tissue-specific toxicity among inbred mouse strains: liver effects. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2015; 78:15-31. [PMID: 25424544 PMCID: PMC4281929 DOI: 10.1080/15287394.2015.958417] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Trichloroethylene (TCE) is a widely used organic solvent. Although TCE is classified as carcinogenic to humans, substantial gaps remain in our understanding of interindividual variability in TCE metabolism and toxicity, especially in the liver. A hypothesis was tested that amounts of oxidative metabolites of TCE in mouse liver are associated with hepatic-specific toxicity. Oral dosing with TCE was conducted in subacute (600 mg/kg/d; 5 d; 7 inbred mouse strains) and subchronic (100 or 400 mg/kg/d; 1, 2, or 4 wk; 2 inbred mouse strains) designs. The quantitative relationship was evaluated between strain-, dose-, and time-dependent formation of TCE metabolites from cytochrome P-450-mediated oxidation (trichloroacetic acid [TCA], dichloroacetic acid [DCA], and trichloroethanol) and glutathione conjugation [S-(1,2-dichlorovinyl)-L-cysteine and S-(1,2-dichlorovinyl)glutathione] in serum and liver, and various hepatic toxicity phenotypes. In subacute study, interstrain variability in TCE metabolite amounts was observed in serum and liver. No marked induction of Cyp2e1 protein levels in liver was detected. Serum and hepatic levels of TCA and DCA were correlated with increased transcription of peroxisome proliferator-marker genes Cyp4a10 and Acox1 but not with degree of induction in hepatocellular proliferation. In subchronic study, serum and liver levels of oxidative metabolites gradually decreased over time despite continuous dosing. Hepatic protein levels of CYP2E1, ADH, and ALDH2 were unaffected by treatment with TCE. While the magnitude of induction of peroxisome proliferator-marker genes also declined, hepatocellular proliferation increased. This study offers a unique opportunity to provide a scientific data-driven rationale for some of the major assumptions in human health assessment of TCE.
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Affiliation(s)
- Hong Sik Yoo
- a Department of Environmental Sciences and Engineering , University of North Carolina at Chapel Hill , Chapel Hill , North Carolina , USA
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Trichloroethylene-induced gene expression and DNA methylation changes in B6C3F1 mouse liver. PLoS One 2014; 9:e116179. [PMID: 25549359 PMCID: PMC4280179 DOI: 10.1371/journal.pone.0116179] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 12/03/2014] [Indexed: 12/31/2022] Open
Abstract
Trichloroethylene (TCE), widely used as an organic solvent in the industry, is a common contaminant in air, soil, and water. Chronic TCE exposure induced hepatocellular carcinoma in mice, and occupational exposure in humans was suggested to be associated with liver cancer. To understand the role of non-genotoxic mechanism(s) for TCE action, we examined the gene expression and DNA methylation changes in the liver of B6C3F1 mice orally administered with TCE (0, 100, 500 and 1000 mg/kg b.w. per day) for 5 days. After 5 days TCE treatment at a dose level of 1000 mg/kg b.w., a total of 431 differentially expressed genes were identified in mouse liver by microarray, of which 291 were up-regulated and 140 down-regulated. The expression changed genes were involved in key signal pathways including PPAR, proliferation, apoptosis and homologous recombination. Notably, the expression level of a number of vital genes involved in the regulation of DNA methylation, such as Utrf1, Tet2, DNMT1, DNMT3a and DNMT3b, were dysregulated. Although global DNA methylation change was not detected in the liver of mice exposed to TCE, the promoter regions of Cdkn1a and Ihh were found to be hypo- and hypermethylated respectively, which correlated negatively with their mRNA expression changes. Furthermore, the gene expression and DNA methylation changes induced by TCE were dose dependent. The overall data indicate that TCE exposure leads to aberrant DNA methylation changes, which might alter the expression of genes involved in the TCE-induced liver tumorgenesis.
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Jiang Y, Chen J, Tong J, Chen T. Trichloroethylene-induced gene expression and DNA methylation changes in B6C3F1 mouse liver. PLoS One 2014. [PMID: 25549359 DOI: 10.1371/-journal.pone.0116179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Trichloroethylene (TCE), widely used as an organic solvent in the industry, is a common contaminant in air, soil, and water. Chronic TCE exposure induced hepatocellular carcinoma in mice, and occupational exposure in humans was suggested to be associated with liver cancer. To understand the role of non-genotoxic mechanism(s) for TCE action, we examined the gene expression and DNA methylation changes in the liver of B6C3F1 mice orally administered with TCE (0, 100, 500 and 1000 mg/kg b.w. per day) for 5 days. After 5 days TCE treatment at a dose level of 1000 mg/kg b.w., a total of 431 differentially expressed genes were identified in mouse liver by microarray, of which 291 were up-regulated and 140 down-regulated. The expression changed genes were involved in key signal pathways including PPAR, proliferation, apoptosis and homologous recombination. Notably, the expression level of a number of vital genes involved in the regulation of DNA methylation, such as Utrf1, Tet2, DNMT1, DNMT3a and DNMT3b, were dysregulated. Although global DNA methylation change was not detected in the liver of mice exposed to TCE, the promoter regions of Cdkn1a and Ihh were found to be hypo- and hypermethylated respectively, which correlated negatively with their mRNA expression changes. Furthermore, the gene expression and DNA methylation changes induced by TCE were dose dependent. The overall data indicate that TCE exposure leads to aberrant DNA methylation changes, which might alter the expression of genes involved in the TCE-induced liver tumorgenesis.
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Affiliation(s)
- Yan Jiang
- Department of Physiology, School of Biology and Basic Medical Sciences, Soochow University, Suzhou, China; Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Soochow University, Suzhou, China
| | - Jiahong Chen
- Department of Toxicology, School of Public Health, Soochow University, Suzhou, China; Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Soochow University, Suzhou, China
| | - Jian Tong
- Department of Toxicology, School of Public Health, Soochow University, Suzhou, China; Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Soochow University, Suzhou, China
| | - Tao Chen
- Department of Toxicology, School of Public Health, Soochow University, Suzhou, China; Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Soochow University, Suzhou, China
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Lash LH, Chiu WA, Guyton KZ, Rusyn I. Trichloroethylene biotransformation and its role in mutagenicity, carcinogenicity and target organ toxicity. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2014; 762:22-36. [PMID: 25484616 PMCID: PMC4254735 DOI: 10.1016/j.mrrev.2014.04.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Metabolism is critical for the mutagenicity, carcinogenicity, and other adverse health effects of trichloroethylene (TCE). Despite the relatively small size and simple chemical structure of TCE, its metabolism is quite complex, yielding multiple intermediates and end-products. Experimental animal and human data indicate that TCE metabolism occurs through two major pathways: cytochrome P450 (CYP)-dependent oxidation and glutathione (GSH) conjugation catalyzed by GSH S-transferases (GSTs). Herein we review recent data characterizing TCE processing and flux through these pathways. We describe the catalytic enzymes, their regulation and tissue localization, as well as the evidence for transport and inter-organ processing of metabolites. We address the chemical reactivity of TCE metabolites, highlighting data on mutagenicity of these end-products. Identification in urine of key metabolites, particularly trichloroacetate (TCA), dichloroacetate (DCA), trichloroethanol and its glucuronide (TCOH and TCOG), and N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine (NAcDCVC), in exposed humans and other species (mostly rats and mice) demonstrates function of the two metabolic pathways in vivo. The CYP pathway primarily yields chemically stable end-products. However, the GST pathway conjugate S-(1,2-dichlorovinyl)glutathione (DCVG) is further processed to multiple highly reactive species that are known to be mutagenic, especially in kidney where in situ metabolism occurs. TCE metabolism is highly variable across sexes, species, tissues and individuals. Genetic polymorphisms in several of the key enzymes metabolizing TCE and its intermediates contribute to variability in metabolic profiles and rates. In all, the evidence characterizing the complex metabolism of TCE can inform predictions of adverse responses including mutagenesis, carcinogenesis, and acute and chronic organ-specific toxicity.
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Affiliation(s)
- Lawrence H. Lash
- Department of Pharmacology, Wayne State University School of Medicine, 540 East Canfield Avenue, Detroit, MI, 48201 USA
| | - Weihsueh A. Chiu
- U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue, NW, Washington, DC, 20460 USA; Chiu.Weihsueh@.epa.gov;
| | - Kathryn Z. Guyton
- U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue, NW, Washington, DC, 20460 USA; Chiu.Weihsueh@.epa.gov;
| | - Ivan Rusyn
- Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599 USA;
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Kopec AK, Sullivan BP, Kassel KM, Joshi N, Luyendyk JP. Toxicogenomic analysis reveals profibrogenic effects of trichloroethylene in autoimmune-mediated cholangitis in mice. Toxicol Sci 2014; 141:515-23. [PMID: 25055964 DOI: 10.1093/toxsci/kfu148] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Epidemiological studies suggest that exposure to environmental chemicals increases the risk of developing autoimmune liver disease. However, the identity of specific chemical perpetrators and the mechanisms whereby environmental chemicals modify liver disease is unclear. Previous studies link exposure to trichloroethylene (TCE) with the development of autoimmune liver disease and exacerbation of autoimmunity in lupus-prone MRL mice. In this study, we utilized NOD.c3c4 mice, which spontaneously develop autoimmune cholangitis bearing resemblance to some features of primary biliary cirrhosis. Nine-week-old female NOD.c3c4 mice were given TCE (0.5 mg/ml) or its vehicle (1% Cremophor-EL) in drinking water for 4 weeks. TCE had little effect on clinical chemistry, biliary cyst formation, or hepatic CD3+ T-cell accumulation. Hepatic microarray profiling revealed a dramatic suppression of early growth response 1 (EGR1) mRNA in livers of TCE-treated mice, which was verified by qPCR and immunohistochemical staining. Consistent with a reported link between reduced EGR1 expression and liver fibrosis, TCE increased hepatic type I collagen (COL1A1) mRNA and protein levels in livers of NOD.c3c4 mice. In contrast, TCE did not increase COL1A1 expression in NOD.ShiLtJ mice, which do not develop autoimmune cholangitis. These results suggest that in the context of concurrent autoimmune liver disease with a genetic basis, modification of hepatic gene expression by TCE may increase profibrogenic signaling in the liver. Moreover, these studies suggest that NOD.c3c4 mice may be a novel model to study gene-environment interactions critical for the development of autoimmune liver disease.
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Affiliation(s)
- Anna K Kopec
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, Michigan 48824
| | - Bradley P Sullivan
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, Kansas 66160
| | - Karen M Kassel
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, Kansas 66160
| | - Nikita Joshi
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan 48824
| | - James P Luyendyk
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, Michigan 48824
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Chiu WA, Campbell JL, Clewell HJ, Zhou YH, Wright FA, Guyton KZ, Rusyn I. Physiologically based pharmacokinetic (PBPK) modeling of interstrain variability in trichloroethylene metabolism in the mouse. ENVIRONMENTAL HEALTH PERSPECTIVES 2014; 122:456-63. [PMID: 24518055 PMCID: PMC4014769 DOI: 10.1289/ehp.1307623] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 02/10/2014] [Indexed: 05/22/2023]
Abstract
BACKGROUND Quantitative estimation of toxicokinetic variability in the human population is a persistent challenge in risk assessment of environmental chemicals. Traditionally, interindividual differences in the population are accounted for by default assumptions or, in rare cases, are based on human toxicokinetic data. OBJECTIVES We evaluated the utility of genetically diverse mouse strains for estimating toxicokinetic population variability for risk assessment, using trichloroethylene (TCE) metabolism as a case study. METHODS We used data on oxidative and glutathione conjugation metabolism of TCE in 16 inbred and 1 hybrid mouse strains to calibrate and extend existing physiologically based pharmacokinetic (PBPK) models. We added one-compartment models for glutathione metabolites and a two-compartment model for dichloroacetic acid (DCA). We used a Bayesian population analysis of interstrain variability to quantify variability in TCE metabolism. RESULTS Concentration-time profiles for TCE metabolism to oxidative and glutathione conjugation metabolites varied across strains. Median predictions for the metabolic flux through oxidation were less variable (5-fold range) than that through glutathione conjugation (10-fold range). For oxidative metabolites, median predictions of trichloroacetic acid production were less variable (2-fold range) than DCA production (5-fold range), although the uncertainty bounds for DCA exceeded the predicted variability. CONCLUSIONS Population PBPK modeling of genetically diverse mouse strains can provide useful quantitative estimates of toxicokinetic population variability. When extrapolated to lower doses more relevant to environmental exposures, mouse population-derived variability estimates for TCE metabolism closely matched population variability estimates previously derived from human toxicokinetic studies with TCE, highlighting the utility of mouse interstrain metabolism studies for addressing toxicokinetic variability.
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Affiliation(s)
- Weihsueh A Chiu
- National Center for Environmental Assessment, Office of Research and Development, U.S. Environmental Protection Agency, Washington, DC, USA
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Rusyn I, Chiu WA, Lash LH, Kromhout H, Hansen J, Guyton KZ. Trichloroethylene: Mechanistic, epidemiologic and other supporting evidence of carcinogenic hazard. Pharmacol Ther 2013; 141:55-68. [PMID: 23973663 DOI: 10.1016/j.pharmthera.2013.08.004] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 07/31/2013] [Indexed: 02/09/2023]
Abstract
The chlorinated solvent trichloroethylene (TCE) is a ubiquitous environmental pollutant. The carcinogenic hazard of TCE was the subject of a 2012 evaluation by a Working Group of the International Agency for Research on Cancer (IARC). Information on exposures, relevant data from epidemiologic studies, bioassays in experimental animals, and toxicity and mechanism of action studies was used to conclude that TCE is carcinogenic to humans (Group 1). This article summarizes the key evidence forming the scientific bases for the IARC classification. Exposure to TCE from environmental sources (including hazardous waste sites and contaminated water) is common throughout the world. While workplace use of TCE has been declining, occupational exposures remain of concern, especially in developing countries. The strongest human evidence is from studies of occupational TCE exposure and kidney cancer. Positive, although less consistent, associations were reported for liver cancer and non-Hodgkin lymphoma. TCE is carcinogenic at multiple sites in multiple species and strains of experimental animals. The mechanistic evidence includes extensive data on the toxicokinetics and genotoxicity of TCE and its metabolites. Together, available evidence provided a cohesive database supporting the human cancer hazard of TCE, particularly in the kidney. For other target sites of carcinogenicity, mechanistic and other data were found to be more limited. Important sources of susceptibility to TCE toxicity and carcinogenicity were also reviewed by the Working Group. In all, consideration of the multiple evidence streams presented herein informed the IARC conclusions regarding the carcinogenicity of TCE.
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Affiliation(s)
- Ivan Rusyn
- University of North Carolina, Chapel Hill, NC, USA.
| | | | | | | | - Johnni Hansen
- Danish Cancer Society Research Center, Copenhagen, Denmark
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Zeise L, Bois FY, Chiu WA, Hattis D, Rusyn I, Guyton KZ. Addressing human variability in next-generation human health risk assessments of environmental chemicals. ENVIRONMENTAL HEALTH PERSPECTIVES 2013; 121:23-31. [PMID: 23086705 PMCID: PMC3553440 DOI: 10.1289/ehp.1205687] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 10/19/2012] [Indexed: 05/19/2023]
Abstract
BACKGROUND Characterizing variability in the extent and nature of responses to environmental exposures is a critical aspect of human health risk assessment. OBJECTIVE Our goal was to explore how next-generation human health risk assessments may better characterize variability in the context of the conceptual framework for the source-to-outcome continuum. METHODS This review was informed by a National Research Council workshop titled "Biological Factors that Underlie Individual Susceptibility to Environmental Stressors and Their Implications for Decision-Making." We considered current experimental and in silico approaches, and emerging data streams (such as genetically defined human cells lines, genetically diverse rodent models, human omic profiling, and genome-wide association studies) that are providing new types of information and models relevant for assessing interindividual variability for application to human health risk assessments of environmental chemicals. DISCUSSION One challenge for characterizing variability is the wide range of sources of inherent biological variability (e.g., genetic and epigenetic variants) among individuals. A second challenge is that each particular pair of health outcomes and chemical exposures involves combinations of these sources, which may be further compounded by extrinsic factors (e.g., diet, psychosocial stressors, other exogenous chemical exposures). A third challenge is that different decision contexts present distinct needs regarding the identification-and extent of characterization-of interindividual variability in the human population. CONCLUSIONS Despite these inherent challenges, opportunities exist to incorporate evidence from emerging data streams for addressing interindividual variability in a range of decision-making contexts.
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Affiliation(s)
- Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Oakland, California 94612, USA.
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Harrill AH, Desmet KD, Wolf KK, Bridges AS, Eaddy JS, Kurtz CL, Hall JE, Paine MF, Tidwell RR, Watkins PB. A mouse diversity panel approach reveals the potential for clinical kidney injury due to DB289 not predicted by classical rodent models. Toxicol Sci 2012; 130:416-26. [PMID: 22940726 PMCID: PMC3498743 DOI: 10.1093/toxsci/kfs238] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
DB289 is the first oral drug shown in clinical trials to have efficacy in treating African trypanosomiasis (African sleeping sickness). Mild liver toxicity was noted but was not treatment limiting. However, development of DB289 was terminated when several treated subjects developed severe kidney injury, a liability not predicted from preclinical testing. We tested the hypothesis that the kidney safety liability of DB289 would be detected in a mouse diversity panel (MDP) comprised of 34 genetically diverse inbred mouse strains. MDP mice received 10 days of oral treatment with DB289 or vehicle and classical renal biomarkers blood urea nitrogen (BUN) and serum creatinine (sCr), as well as urine biomarkers of kidney injury were measured. While BUN and sCr remained within reference ranges, marked elevations were observed for kidney injury molecule-1 (KIM-1) in the urine of sensitive mouse strains. KIM-1 elevations were not always coincident with elevations in alanine aminotransferase (ALT), suggesting that renal injury was not linked to hepatic injury. Genome-wide association analyses of KIM-1 elevations indicated that genes participating in cholesterol and lipid biosynthesis and transport, oxidative stress, and cytokine release may play a role in DB289 renal injury. Taken together, the data resulting from this study highlight the utility of using an MDP to predict clinically relevant toxicities, to identify relevant toxicity biomarkers that may translate into the clinic, and to identify potential mechanisms underlying toxicities. In addition, the sensitive mouse strains identified in this study may be useful in screening next-in-class compounds for renal injury.
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Affiliation(s)
- Alison H Harrill
- The Hamner Institutes for Health Sciences, Hamner-University of North Carolina Institute for Drug Safety Sciences, Durham, North Carolina 27709, USA.
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Geng XC, Li B, Zhang L, Song Y, Lin Z, Zhang YQ, Wang JZ. Corn oil as a vehicle in drug development exerts a dose-dependent effect on gene expression profiles in rat thymus. J Appl Toxicol 2012; 32:850-7. [DOI: 10.1002/jat.2773] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2012] [Revised: 04/09/2012] [Accepted: 04/09/2012] [Indexed: 12/20/2022]
Affiliation(s)
| | - Bo Li
- National Institute for Food and Drug Control; Beijing; 100050; People's Republic of China
| | - Liang Zhang
- BioChain (Beijing) Science and Technology Inc.; Beijing; 100176; People's Republic of China
| | - Ying Song
- School of Pharmaceutical Science; Sun Yat-sen University; Guangzhou; 510006; People's Republic of China
| | - Zhi Lin
- National Institute for Food and Drug Control; Beijing; 100050; People's Republic of China
| | - Ying-Qi Zhang
- Biotechnology Center, School of Pharmacy; The Fourth Military Medical University; Xi'an; 710032; People's Republic of China
| | - Jun-Zhi Wang
- National Institute for Food and Drug Control; Beijing; 100050; People's Republic of China
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Shi P, Zhang XX, Zhang Z, Zhang Y, Wu B, Cheng S, Li A. Chronic exposure to contaminated drinking water stimulates PPAR expression in mice livers. CHEMOSPHERE 2012; 88:407-412. [PMID: 22445956 DOI: 10.1016/j.chemosphere.2012.02.055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 02/10/2012] [Accepted: 02/20/2012] [Indexed: 05/31/2023]
Abstract
Mice were fed with source water (SW) and tap water (TW) for 90 d to evaluate hepatotoxicity induced by the drinking water. Histopathologic observation showed no obvious damage to hepatic tissue in the SW and TW groups. However, microarray analysis indicated that the SW and TW exposures affected many metabolic pathways, among which PPAR (peroxisome proliferator-activated receptors) signaling was most susceptible. Immunohistochemical staining demonstrated that both PPAR-α and PPAR-γ were significantly increased in the exposure groups compared to control. Enzyme-linked immunosorbent assay revealed that PPAR-α expression level was increased from 23.37±0.53 ng g(-1) liver weight in control group to 26.60±1.43 ng g(-1) liver weight in SW group and 27.68±1.10 ng g(-1) liver weight in TW group (p<0.05). For PPAR-γ, the expression level was also significantly enhanced from 0.83±0.07 ng g(-1) liver weight in control group to 1.11±0.20 ng g(-1) liver weight in SW group and 1.16±0.07 ng g(-1) liver weight in TW group (p<0.05). The SW and DW posed no obvious hepatotoxicity on mice and PPAR-α/-γ could be used as a novel biomarker to assess public health risk induced by slightly contaminated drinking water.
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Affiliation(s)
- Peng Shi
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046, China
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Abstract
Tox21 is a transformative effort on the part of several U.S. Federal agencies (the National Toxicology Program/National Institute of Environmental Health Sciences [NTP], the National Institutes of Health (NIH) Chemical Genomics Center/National Human Genome Research Institute [NCGC; now called the NIH Center for Translational Therapeutics, National Center for Advancing Translational Sciences] the Environmental Protection Agency's (EPA) National Center for Computational Toxicology, and recently the Food and Drug Administration) that are partnering to fundamentally change the science of safety toxicology. These agencies bring a comprehensive suite of capabilities and are working diligently together to develop, evaluate, and ultimately implement a new safety assessment paradigm. Toxicologic pathology has an important ongoing role in establishing the validity of this transformation, and may ultimately benefit as a discipline through an enhanced understanding of chemically induced disease mechanisms.
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Affiliation(s)
- John R Bucher
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA.
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Abstract
The Mouse Phenome Project was launched a decade ago to complement mouse genome sequencing efforts by promoting new phenotyping initiatives under standardized conditions and collecting the data in a central public database, the Mouse Phenome Database (MPD; http://phenome.jax.org). MPD houses a wealth of strain characteristics data to facilitate the use of the laboratory mouse in translational research for human health and disease, helping alleviate problems involving experimentation in humans that cannot be done practically or ethically. Data sets are voluntarily contributed by researchers from a variety of institutions and settings, or in some cases, retrieved by MPD staff from public sources. MPD maintains a growing collection of standardized reference data that assists investigators in selecting mouse strains for research applications; houses treatment/control data for drug studies and other interventions; offers a standardized platform for discovering genotype-phenotype relationships; and provides tools for hypothesis testing. MPD improvements and updates since our last NAR report are presented, including the addition of new tools and features to facilitate navigation and data mining as well as the acquisition of new data (phenotypic, genotypic and gene expression).
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Affiliation(s)
- Terry P Maddatu
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
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Koturbash I, Scherhag A, Sorrentino J, Sexton K, Bodnar W, Swenberg JA, Beland FA, Pardo-Manuel deVillena F, Rusyn I, Pogribny IP. Epigenetic mechanisms of mouse interstrain variability in genotoxicity of the environmental toxicant 1,3-butadiene. Toxicol Sci 2011; 122:448-56. [PMID: 21602187 PMCID: PMC3155089 DOI: 10.1093/toxsci/kfr133] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Accepted: 05/11/2011] [Indexed: 12/18/2022] Open
Abstract
1,3-Butadiene (BD) is a common environmental contaminant classified as "carcinogenic to humans." Formation of BD-induced DNA adducts plays a major role in its carcinogenicity. BD is also an epigenotoxic agent (i.e., it affects DNA and histone methylation in the liver). We used a panel of genetically diverse inbred mice (NOD/LtJ, CAST/EiJ, A/J, WSB/EiJ, PWK/PhJ, C57BL/6J, and 129S1/SvImJ) to assess whether BD-induced genotoxic and epigenotoxic events may be subject to interstrain differences. Mice (male, 7 weeks) were exposed via inhalation to 0 or 625 ppm BD for 6 h/day and 5 days/week for 2 weeks and liver BD-DNA adducts, epigenetic alterations, and liver toxicity were assessed. N-7-(2,3,4-trihydroxybut-1-yl)-guanine adducts were detected in all strains after exposure, yet BD-induced DNA damage in CAST/EiJ mice was two to three times lower. Epigenetic effects of BD were most prominent in C57BL/6J mice where loss of global DNA methylation and loss of trimethylation of histone H3 lysine 9, histone H3 lysine 27, and histone H4 lysine 20, accompanied by dysregulation of liver gene expression indicative of hepatotoxicity, were found. Interestingly, we observed an increase in histone methylation in the absence of changes in gene expression and DNA methylation in CAST/EiJ strain. We hypothesized that mitigated genotoxicity of BD in CAST/EiJ mice may be due to chromatin condensation. Indeed, we show that in response to BD exposure, chromatin condensation occurs in CAST/EiJ, whereas the opposite effect is observed in C57BL/6J mice. These findings demonstrate that interstrain susceptibility to genotoxicity by a well-known environmental carcinogen may be due to strain-specific epigenetic events in response to the exposure.
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Affiliation(s)
- Igor Koturbash
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079
| | - Anne Scherhag
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079
- Technical University of Kaiserslautern, Kaiserslautern, Rheinland-Pfalz 67663, Germany
| | | | | | - Wanda Bodnar
- Department of Environmental Sciences and Engineering
| | - James A. Swenberg
- Curriculum in Toxicology
- Department of Environmental Sciences and Engineering
| | - Frederick A. Beland
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079
| | | | - Ivan Rusyn
- Curriculum in Toxicology
- Department of Environmental Sciences and Engineering
| | - Igor P. Pogribny
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079
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