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Eaton DL, Simon TW, Kaminski NE, Perdew GH, Nebert DW. Species differences in specific ligand-binding affinity and activation of AHR: The biological basis for calculation of relative effective potencies and toxic equivalence factors. Regul Toxicol Pharmacol 2024; 149:105598. [PMID: 38548044 DOI: 10.1016/j.yrtph.2024.105598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/25/2024] [Accepted: 03/05/2024] [Indexed: 05/01/2024]
Abstract
In 2022 the World Health Organization (WHO) published updated 'Toxic Equivalence Factors' (TEFs) for a wide variety of chlorinated dioxins, dibenzofurans and PCBs [collectively referred to as 'dioxin-like chemicals'; DLCs) that interact with the aryl hydrocarbon receptor (AHR)]. Their update used sophisticated statistical analysis of hundreds of published studies that reported estimation of 'Relative Effective Potency' (REP) values for individual DLC congeners. The weighting scheme used in their assessment of each study favored in vivo over in vitro studies and was based largely on rodent studies. In this Commentary, we highlight the large body of published studies that demonstrate large species differences in AHR-ligand activation and provide supporting evidence for our position that the WHO 2022 TEF values intended for use in human risk assessment of DLC mixtures will provide highly misleading overestimates of 'Toxic Equivalent Quotients' (TEQs), because of well-recognized striking differences in AHR ligand affinities between rodent (rat, mouse) and human. The data reviewed in our Commentary support the position that human tissue-derived estimates of REP/TEF values for individual DLC congeners, although uncertain, will provide much better, more realistic estimates of potential activation of the human AHR, when exposure to complex DLC mixtures occurs.
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Affiliation(s)
- David L Eaton
- Department of Environmental Occupational Health Sciences, School of Public Health, University of Washington, Seattle, WA, USA.
| | | | - Norbert E Kaminski
- Department of Pharmacology and Toxicology, Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
| | - Gary H Perdew
- The Pennsylvania State University, State College, PA, USA
| | - Daniel W Nebert
- Department of Environmental and Public Health Sciences, Center for Environmental Genetics, University of Cincinnati College of Medicine, USA; Department of Pediatrics & Molecular Developmental Biology, Division of Human Genetics, Cincinnati Children's Research Foundation, Cincinnati, OH, USA
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2
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Zhou Y, Chen Q, Klaunig JE, Shao K. A mode of action-based probabilistic framework of dose-response assessment for nonmutagenic liver carcinogens: a case study of PCB-126. Toxicol Sci 2023; 196:250-260. [PMID: 37643630 PMCID: PMC10682966 DOI: 10.1093/toxsci/kfad091] [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: 08/31/2023] Open
Abstract
A main function of dose-response assessment is to estimate a "safe" dose in the target population to support chemical risk assessment. Typically, a "safe" dose is developed differently for cancer and noncancer effects based on a 2-step procedure, ie, point of departure (POD) derivation and low-dose extrapolation. However, the current dose-response assessment framework is criticized for its dichotomized strategy without integrating the mode of action (MOA) information. The objective of this study was, based on our previous work, to develop a MOA-based probabilistic dose-response framework that quantitatively synthesizes a biological pathway in a dose-response modeling process to estimate the risk of chemicals that have carcinogenic potential. 3,3',4,4',5-Pentachlorobiphenyl (PCB-126) was exemplified to demonstrate our proposed approach. There were 4 major steps in the new modeling framework, including (1) key quantifiable events (KQEs) identification and extraction, (2) essential dose calculation, (3) MOA-based POD derivation, and (4) MOA-based probabilistic reference dose (RfD) estimation. Compared with reported PODs and traditional RfDs, the MOA-based estimates derived from our approach were comparable and plausible. One key feature of our approach was the use of overall MOA information to build the dose-response relationship on the entire dose continuum including the low-dose region. On the other hand, by adjusting uncertainty and variability in a probabilistic manner, the MOA-based probabilistic RfDs can provide useful insights of health protection for the specific proportion of population. Moreover, the proposed framework had important potential to be generalized to assess different types of chemicals other than nonmutagenic carcinogens, highlighting its utility to improve current chemical risk assessment.
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Affiliation(s)
- Yun Zhou
- Department of Environmental and Occupational Health, School of Public Health—Bloomington, Indiana University, Bloomington, Indiana 47405, USA
| | - Qiran Chen
- Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, Florida 32610, USA
| | - James E Klaunig
- Department of Environmental and Occupational Health, School of Public Health—Bloomington, Indiana University, Bloomington, Indiana 47405, USA
| | - Kan Shao
- Department of Environmental and Occupational Health, School of Public Health—Bloomington, Indiana University, Bloomington, Indiana 47405, USA
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3
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Cholico GN, Orlowska K, Fling RR, Sink WJ, Zacharewski NA, Fader KA, Nault R, Zacharewski T. Consequences of reprogramming acetyl-CoA metabolism by 2,3,7,8-tetrachlorodibenzo-p-dioxin in the mouse liver. Sci Rep 2023; 13:4138. [PMID: 36914879 PMCID: PMC10011583 DOI: 10.1038/s41598-023-31087-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 03/06/2023] [Indexed: 03/14/2023] Open
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a persistent environmental contaminant that induces the progression of steatosis to steatohepatitis with fibrosis in mice. Furthermore, TCDD reprograms hepatic metabolism by redirecting glycolytic intermediates while inhibiting lipid metabolism. Here, we examined the effect of TCDD on hepatic acetyl-coenzyme A (acetyl-CoA) and β-hydroxybutyrate levels as well as protein acetylation and β-hydroxybutyrylation. Acetyl-CoA is not only a central metabolite in multiple anabolic and catabolic pathways, but also a substrate used for posttranslational modification of proteins and a surrogate indicator of cellular energy status. Targeted metabolomic analysis revealed a dose-dependent decrease in hepatic acetyl-CoA levels coincident with the phosphorylation of pyruvate dehydrogenase (E1), and the induction of pyruvate dehydrogenase kinase 4 and pyruvate dehydrogenase phosphatase, while repressing ATP citrate lyase and short-chain acyl-CoA synthetase gene expression. In addition, TCDD dose-dependently reduced the levels of hepatic β-hydroxybutyrate and repressed ketone body biosynthesis gene expression. Moreover, levels of total hepatic protein acetylation and β-hydroxybutyrylation were reduced. AMPK phosphorylation was induced consistent with acetyl-CoA serving as a cellular energy status surrogate, yet subsequent targets associated with re-establishing energy homeostasis were not activated. Collectively, TCDD reduced hepatic acetyl-CoA and β-hydroxybutyrate levels eliciting starvation-like conditions despite normal levels of food intake.
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Affiliation(s)
- Giovan N Cholico
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Karina Orlowska
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Russell R Fling
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
- Microbiology & Molecular Genetics, Michigan State University, East Lansing, MI, 48824, USA
| | - Warren J Sink
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Nicholas A Zacharewski
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
| | - Kelly A Fader
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Rance Nault
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Tim Zacharewski
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA.
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA.
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4
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Grishanova AY, Perepechaeva ML. Aryl Hydrocarbon Receptor in Oxidative Stress as a Double Agent and Its Biological and Therapeutic Significance. Int J Mol Sci 2022; 23:ijms23126719. [PMID: 35743162 PMCID: PMC9224361 DOI: 10.3390/ijms23126719] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/14/2022] [Accepted: 06/14/2022] [Indexed: 12/02/2022] Open
Abstract
The aryl hydrocarbon receptor (AhR) has long been implicated in the induction of a battery of genes involved in the metabolism of xenobiotics and endogenous compounds. AhR is a ligand-activated transcription factor necessary for the launch of transcriptional responses important in health and disease. In past decades, evidence has accumulated that AhR is associated with the cellular response to oxidative stress, and this property of AhR must be taken into account during investigations into a mechanism of action of xenobiotics that is able to activate AhR or that is susceptible to metabolic activation by enzymes encoded by the genes that are under the control of AhR. In this review, we examine various mechanisms by which AhR takes part in the oxidative-stress response, including antioxidant and prooxidant enzymes and cytochrome P450. We also show that AhR, as a participant in the redox balance and as a modulator of redox signals, is being increasingly studied as a target for a new class of therapeutic compounds and as an explanation for the pathogenesis of some disorders.
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5
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Mertowska P, Mertowski S, Wojnicka J, Korona-Głowniak I, Grywalska E, Błażewicz A, Załuska W. A Link between Chronic Kidney Disease and Gut Microbiota in Immunological and Nutritional Aspects. Nutrients 2021; 13:3637. [PMID: 34684638 PMCID: PMC8540836 DOI: 10.3390/nu13103637] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/14/2021] [Accepted: 10/15/2021] [Indexed: 02/07/2023] Open
Abstract
Chronic kidney disease (CKD) is generally progressive and irreversible, structural or functional renal impairment for 3 or more months affecting multiple metabolic pathways. Recently, the composition, dynamics, and stability of a patient's microbiota has been noted to play a significant role during disease onset or progression. Increasing urea concentration during CKD can lead to an acceleration of the process of kidney injury leading to alterations in the intestinal microbiota that can increase the production of gut-derived toxins and alter the intestinal epithelial barrier. A detailed analysis of the relationship between the role of intestinal microbiota and the development of inflammation within the symbiotic and dysbiotic intestinal microbiota showed significant changes in kidney dysfunction. Several recent studies have determined that dietary factors can significantly influence the activation of immune cells and their mediators. Moreover, dietary changes can profoundly affect the balance of gut microbiota. The aim of this review is to present the importance and factors influencing the differentiation of the human microbiota in the progression of kidney diseases, such as CKD, IgA nephropathy, idiopatic nephropathy, and diabetic kidney disease, with particular emphasis on the role of the immune system. Moreover, the effects of nutrients, bioactive compounds on the immune system in development of chronic kidney disease were reviewed.
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Affiliation(s)
- Paulina Mertowska
- Department of Experimental Immunology, Medical University of Lublin, 4a Chodzki Street, 20-093 Lublin, Poland; (P.M.); (S.M.); (E.G.)
| | - Sebastian Mertowski
- Department of Experimental Immunology, Medical University of Lublin, 4a Chodzki Street, 20-093 Lublin, Poland; (P.M.); (S.M.); (E.G.)
| | - Julia Wojnicka
- Department of Pathobiochemistry and Interdisciplinary Applications of Ion Chromatography, Medical University of Lublin, 1 Chodzki Street, 20-093 Lublin, Poland; (J.W.); (A.B.)
| | - Izabela Korona-Głowniak
- Department of Pharmaceutical Microbiology, Medical University of Lublin, 1 Chodzki Street, 20-093 Lublin, Poland
| | - Ewelina Grywalska
- Department of Experimental Immunology, Medical University of Lublin, 4a Chodzki Street, 20-093 Lublin, Poland; (P.M.); (S.M.); (E.G.)
| | - Anna Błażewicz
- Department of Pathobiochemistry and Interdisciplinary Applications of Ion Chromatography, Medical University of Lublin, 1 Chodzki Street, 20-093 Lublin, Poland; (J.W.); (A.B.)
| | - Wojciech Załuska
- Department of Nephrology, Medical University of Lublin, 8 Jaczewskiego Street, 20-954 Lublin, Poland;
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Wikoff DS, Urban JD, Ring C, Britt J, Fitch S, Budinsky R, Haws LC. Development of a Range of Plausible Noncancer Toxicity Values for 2,3,7,8-Tetrachlorodibenzo-p-Dioxin Based on Effects on Sperm Count: Application of Systematic Review Methods and Quantitative Integration of Dose Response Using Meta-Regression. Toxicol Sci 2021; 179:162-182. [PMID: 33306106 DOI: 10.1093/toxsci/kfaa171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Regulatory agencies have derived noncancer toxicity values for 2,3,7,8-tetrachlorodibenzo-p-dioxin based on reduced sperm counts relying on single studies from a large body of evidence. Techniques such as meta-regression allow for greater use of the available data while simultaneously providing important information regarding the uncertainty associated with the underlying evidence base when conducting risk assessments. The objective herein was to apply systematic review methods and meta-regression to characterize the dose-response relationship of gestational exposure and epididymal sperm count. Twenty-three publications (20 animal studies consisting of 29 separate rat experimental data sets, and 3 epidemiology studies) met inclusion criteria. Risk of bias evaluation was performed to critically appraise study validity. Low to very low confidence precluded use of available epidemiological data as candidate studies for dose-response due to inconsistencies across the evidence base, high risk of bias, and general lack of biological coherence, including lack of clinical relevance and dose-response concordance. Experimental animal studies, which were found to have higher confidence following the structured assessment of confidence (eg, controlled exposure, biological consistency), were used as the basis of a meta-regression. Multiple models were fit; points of departure were identified and converted to human equivalent doses. The resulting reference dose estimates ranged from approximately 4 to 70 pg/kg/day, depending on model, benchmark response level, and study validity integration approach. This range of reference doses can be used either qualitatively or quantitatively to enhance understanding of human health risk estimates for dioxin-like compounds.
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7
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El-Dairi R, Huuskonen P, Pasanen M, Rysä J. Aryl hydrocarbon receptor (AhR) agonist β-naphthoflavone regulated gene networks in human primary trophoblasts. Reprod Toxicol 2020; 96:370-379. [PMID: 32858204 DOI: 10.1016/j.reprotox.2020.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 08/16/2020] [Accepted: 08/18/2020] [Indexed: 12/27/2022]
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that is highly expressed in placenta. AhR belongs to a class of transcriptional regulators that control many developmental and physiological events (e.g. xenobiotic metabolism). Our study describes AhR regulated transcriptional responses in human primary trophoblast by using the AhR agonist, β-naphthoflavone (BNF). Human primary trophoblast cells were isolated from full term placenta after delivery. The trophoblasts were exposed to 25 μM of AhR agonist, BNF, for 72 hours. Gene expression profiling was conducted with Illumina HT-12 expression beadchips. Expression of selected genes was confirmed with RT-qPCR. Ingenuity pathway analysis (IPA) was used to predict functional pathways and upstream regulators of differentially expressed genes in order to identify regulatory networks associated with AhR. In response to BNF exposure, 64 genes were upregulated, and 257 genes were downregulated compared to control trophoblasts (±1.5-fold, p < 0.05). BNF regulated genes included placental hormones and genes implicated in immune- and inflammatory responses in addition to their well-known effects on xenobiotic metabolism, oxidative stress, antioxidant defense. In conclusion, these results show that BNF has wide-ranging effects on placental gene expression beyond xenobiotic metabolism e.g. disruption of inflammatory processes and hormones in the placenta.
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Affiliation(s)
- Rami El-Dairi
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland.
| | - Pasi Huuskonen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland.
| | - Markku Pasanen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland.
| | - Jaana Rysä
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland.
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8
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Borro M, Di Girolamo P, Gentile G, De Luca O, Preissner R, Marcolongo A, Ferracuti S, Simmaco M. Evidence-Based Considerations Exploring Relations between SARS-CoV-2 Pandemic and Air Pollution: Involvement of PM2.5-Mediated Up-Regulation of the Viral Receptor ACE-2. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E5573. [PMID: 32748812 PMCID: PMC7432777 DOI: 10.3390/ijerph17155573] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 07/27/2020] [Accepted: 07/31/2020] [Indexed: 12/23/2022]
Abstract
The COVID-19/SARS-CoV-2 pandemic struck health, social and economic systems worldwide, and represents an open challenge for scientists -coping with the high inter-individual variability of COVID-19, and for policy makers -coping with the responsibility to understand environmental factors affecting its severity across different geographical areas. Air pollution has been warned of as a modifiable factor contributing to differential SARS-CoV-2 spread but the biological mechanisms underlying the phenomenon are still unknown. Air quality and COVID-19 epidemiological data from 110 Italian provinces were studied by correlation analysis, to evaluate the association between particulate matter (PM)2.5 concentrations and incidence, mortality rate and case fatality risk of COVID-19 in the period 20 February-31 March 2020. Bioinformatic analysis of the DNA sequence encoding the SARS-CoV-2 cell receptor angiotensin-converting enzyme 2 (ACE-2) was performed to identify consensus motifs for transcription factors mediating cellular response to pollutant insult. Positive correlations between PM2.5 levels and the incidence (r = 0.67, p < 0.0001), the mortality rate (r = 0.65, p < 0.0001) and the case fatality rate (r = 0.7, p < 0.0001) of COVID-19 were found. The bioinformatic analysis of the ACE-2 gene identified nine putative consensus motifs for the aryl hydrocarbon receptor (AHR). Our results confirm the supposed link between air pollution and the rate and outcome of SARS-CoV-2 infection and support the hypothesis that pollution-induced over-expression of ACE-2 on human airways may favor SARS-CoV-2 infectivity.
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Affiliation(s)
- Marina Borro
- Laboratory of Clinical Biochemistry, University Hospital Sant’Andrea, Department of Neurosciences, Mental Health and Sensory Organs, Faculty of Medicine and Psychology, Sapienza University, via di Grottarossa 1035, 00189 Rome, Italy; (M.B.); (G.G.)
| | - Paolo Di Girolamo
- School of Engineering, University of Basilicata, viale dell’Ateneo Lucano 10, 85100 Potenza, Italy;
| | - Giovanna Gentile
- Laboratory of Clinical Biochemistry, University Hospital Sant’Andrea, Department of Neurosciences, Mental Health and Sensory Organs, Faculty of Medicine and Psychology, Sapienza University, via di Grottarossa 1035, 00189 Rome, Italy; (M.B.); (G.G.)
| | - Ottavia De Luca
- Laboratory of Clinical Biochemistry, University Hospital Sant’Andrea, via di Grottarossa 1035, 00189 Rome, Italy;
| | - Robert Preissner
- Structural Bioinformatics Group, Charité–Universitätsmedizin Berlin, Philippstr. 12, 10115 Berlin, Germany;
| | - Adriano Marcolongo
- General Direction, University Hospital Sant’Andrea, via di Grottarossa 1035, 00189 Rome, Italy;
| | - Stefano Ferracuti
- Department of Human Neuroscience, Sapienza University, Piazzale Aldo Moro, 5, 00185 Rome, Italy;
| | - Maurizio Simmaco
- Laboratory of Clinical Biochemistry, University Hospital Sant’Andrea, Department of Neurosciences, Mental Health and Sensory Organs, Faculty of Medicine and Psychology, Sapienza University, via di Grottarossa 1035, 00189 Rome, Italy; (M.B.); (G.G.)
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9
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Vogel CFA, Van Winkle LS, Esser C, Haarmann-Stemmann T. The aryl hydrocarbon receptor as a target of environmental stressors - Implications for pollution mediated stress and inflammatory responses. Redox Biol 2020; 34:101530. [PMID: 32354640 PMCID: PMC7327980 DOI: 10.1016/j.redox.2020.101530] [Citation(s) in RCA: 204] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 03/20/2020] [Accepted: 03/31/2020] [Indexed: 02/08/2023] Open
Abstract
The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor regulating the expression of genes, for instance encoding the monooxygenases cytochrome P450 (CYP) 1A1 and CYP1A2, which are important enzymes in metabolism of xenobiotics. The AHR is activated upon binding of polycyclic aromatic hydrocarbons (PAHs), persistent organic pollutants (POPs), and related ubiquitous environmental chemicals, to mediate their biological and toxic effects. In addition, several endogenous and natural compounds can bind to AHR, thereby modulating a variety of physiological processes. In recent years, ambient particulate matter (PM) associated with traffic related air pollution (TRAP) has been found to contain significant amounts of PAHs. PM containing PAHs are of increasing concern as a class of agonists, which can activate the AHR. Several reports show that PM and AHR-mediated induction of CYP1A1 results in excessive generation of reactive oxygen species (ROS), causing oxidative stress. Furthermore, exposure to PM and PAHs induce inflammatory responses and may lead to chronic inflammatory diseases, including asthma, cardiovascular diseases, and increased cancer risk. In this review, we summarize findings showing the critical role that the AHR plays in mediating effects of environmental pollutants and stressors, which pose a risk of impacting the environment and human health. PAHs present on ambient air pollution particles are ligands of the cellular AHR. AHR-dependent induction of CYP1, AKR, NOX and COX-2 genes can be a source of ROS generation. AHR signaling and NRF2 signaling interact to regulate the expression of antioxidant genes. Air pollution and ROS can affect inflammation, which is partially triggered by AHR and associated immune responses. Skin, lung, and the cardiovascular system are major target sites for air pollution-induced inflammation.
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Affiliation(s)
- Christoph F A Vogel
- Center for Health and the Environment, University of California, One Shields Avenue, Davis, CA, 95616, USA; Department of Environmental Toxicology, University of California, One Shields Avenue, Davis, CA, 95616, USA
| | - Laura S Van Winkle
- Center for Health and the Environment, University of California, One Shields Avenue, Davis, CA, 95616, USA; School of Veterinary Medicine Department of Anatomy, University of California, One Shields Avenue, Davis, CA, 5616, USA
| | - Charlotte Esser
- IUF - Leibniz-Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany
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Liu X, Zhang L, Li J, Wang J, Meng G, Chi M, Zhao Y, Wu Y. Relative Effect Potency Estimates for Dioxin-Like Compounds in Pregnant Women with Gestational Diabetes Mellitus and Blood Glucose Outcomes Based on a Nested Case-control Study. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:7792-7802. [PMID: 31149810 DOI: 10.1021/acs.est.9b00988] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
To improve the applicability of the toxic equivalents principle for human health risk assessment, systemic relative effect potencies (REPs) for dioxin-like compounds (DLCs) deriving from human in vivo data are required. A prospective nested case-control study was performed to determine REPs from the human serum concentration of DLCs using gestational diabetes mellitus (GDM) and fasting blood glucose (FBG) as the end points of concern. Serum concentration of 29 DLCs from 77 cases and 154 controls were measured. Logistic and linear regression were used to estimate the effects of individual congeners on GDM and FBG, respectively. The REPs based on GDM and FBG were calculated from the ratios of regression coefficients, βi (DLCs)/βTCDD. Two sets of consistent human serum-based REPs, that is, GDM-REP and FBG-REP, were established and largely agree with REPs from other human studies. These human-serum REPs show much smaller variation compared to the 4 to 5 orders of magnitude span in REPs database for the present WHO-TEF determination. Moreover, the established REPs fitted well with WHO-TEFs, especially for polychlorinated dibenzo- p-dioxins, furans. These REPs reflecting real human exposure scenarios exhibited validity and could be used to improve health risk assessment of human body burden of DLCs.
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Affiliation(s)
- Xin Liu
- NHC Key Laboratory of Food Safety Risk Assessment , China National Center for Food Safety Risk Assessment , Beijing 100021 , China
- State Key Laboratory of Food Science and Technology , Nanchang University , Nanchang 330047 , China
| | - Lei Zhang
- NHC Key Laboratory of Food Safety Risk Assessment , China National Center for Food Safety Risk Assessment , Beijing 100021 , China
| | - Jingguang Li
- NHC Key Laboratory of Food Safety Risk Assessment , China National Center for Food Safety Risk Assessment , Beijing 100021 , China
- State Key Laboratory of Food Science and Technology , Nanchang University , Nanchang 330047 , China
| | - Jun Wang
- Shenzhen Center for Chronic Disease Control , Shenzhen 518020 , China
| | - Guimin Meng
- Beijing Fengtai Hospital obstetrics and gynecology , Beijing 100071 , China
| | - Min Chi
- NHC Key Laboratory of Food Safety Risk Assessment , China National Center for Food Safety Risk Assessment , Beijing 100021 , China
- Taiyuan Center for Disease Control and Prevention , Taiyuan 030000 , China
| | - Yunfeng Zhao
- NHC Key Laboratory of Food Safety Risk Assessment , China National Center for Food Safety Risk Assessment , Beijing 100021 , China
| | - Yongning Wu
- NHC Key Laboratory of Food Safety Risk Assessment , China National Center for Food Safety Risk Assessment , Beijing 100021 , China
- State Key Laboratory of Food Science and Technology , Nanchang University , Nanchang 330047 , China
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11
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Safe S, Han H, Goldsby J, Mohankumar K, Chapkin RS. Aryl Hydrocarbon Receptor (AhR) Ligands as Selective AhR Modulators: Genomic Studies. CURRENT OPINION IN TOXICOLOGY 2018; 11-12:10-20. [PMID: 31453421 DOI: 10.1016/j.cotox.2018.11.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The aryl hydrocarbon receptor (AhR) binds structurally diverse ligands that vary from the environmental toxicant 2,3,7,8-tetrachlorodibenzo-B-dioxin (TCDD) to AhR- active pharmaceuticals and health-promoting phytochemicals. There are remarkable differences in the toxicity of TCDD and related halogenated aromatics (HAs) vs. health promoting AhR ligands, and genomic analysis shows that even among the toxic HAs, there are differences in their regulation of genes and pathways. Thus, like ligands for other receptors, AhR ligands are selective AhR modulators (SAhRMs) which exhibit variable tissue-, organ- and species-specific genomic and functional activities.
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Affiliation(s)
- Stephen Safe
- Department of Veterinary Physiology and Pharmacology
| | - Huajun Han
- Department of Biochemistry & Biophysics
- Department of Nutrition & Food Science
- Program in Integrative Nutrition & Complex Diseases, Texas A&M University, College Station, TX, USA
| | - Jennifer Goldsby
- Department of Nutrition & Food Science
- Program in Integrative Nutrition & Complex Diseases, Texas A&M University, College Station, TX, USA
| | | | - Robert S Chapkin
- Department of Biochemistry & Biophysics
- Department of Nutrition & Food Science
- Program in Integrative Nutrition & Complex Diseases, Texas A&M University, College Station, TX, USA
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12
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Strapáčová S, Brenerová P, Krčmář P, Andersson P, van Ede KI, van Duursen MB, van den Berg M, Vondráček J, Machala M. Relative effective potencies of dioxin-like compounds in rodent and human lung cell models. Toxicology 2018; 404-405:33-41. [DOI: 10.1016/j.tox.2018.05.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 04/11/2018] [Accepted: 05/02/2018] [Indexed: 12/23/2022]
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13
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One TEF concept does not fit all: The case for human risk assessment of polychlorinated biphenyls. CURRENT OPINION IN TOXICOLOGY 2017. [DOI: 10.1016/j.cotox.2017.01.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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14
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Fader KA, Zacharewski TR. Beyond the Aryl Hydrocarbon Receptor: Pathway Interactions in the Hepatotoxicity of 2,3,7,8-Tetrachlorodibenzo- p-dioxin and Related Compounds. CURRENT OPINION IN TOXICOLOGY 2017; 2:36-41. [PMID: 28948239 PMCID: PMC5609723 DOI: 10.1016/j.cotox.2017.01.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the prototypical ligand for a group of environmental halogenated aromatic hydrocarbon contaminants which elicit hepatotoxicity and other toxic responses through activation of the aryl hydrocarbon receptor (AhR). Despite the conservation of the AhR and its signaling pathway, TCDD-elicited differential gene expression networks are species-specific, consistent with differences in sensitivity and toxic responses between species. This review integrates gene expression studies with complementary phenotypic analyses (e.g., metabolomics, clinical biochemistry, and histopathology) to elucidate the pathways through which TCDD and related compounds cause hepatotoxicity beyond AhR activation. We propose that AhR-mediated toxicity is a collective response to the cumulative burden of metabolic reprogramming across multiple pathways. Consequently, nutrition, health status, and genetic background establish the basis for differences in sensitivity and predisposition to adverse outcomes between species, sub-populations, tissues, and cells.
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Affiliation(s)
- Kelly A. Fader
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, 48824
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824
| | - Timothy R. Zacharewski
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, 48824
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824
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15
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Prokopec SD, Houlahan KE, Sun RX, Watson JD, Yao CQ, Lee J, P'ng C, Pang R, Wu AH, Chong LC, Smith AB, Harding NJ, Moffat ID, Lindén J, Lensu S, Okey AB, Pohjanvirta R, Boutros PC. Compendium of TCDD-mediated transcriptomic response datasets in mammalian model systems. BMC Genomics 2017; 18:78. [PMID: 28086803 PMCID: PMC5237151 DOI: 10.1186/s12864-016-3446-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 12/20/2016] [Indexed: 02/04/2023] Open
Abstract
Background 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is the most potent congener of the dioxin class of environmental contaminants. Exposure to TCDD causes a wide range of toxic outcomes, ranging from chloracne to acute lethality. The severity of toxicity is highly dependent on the aryl hydrocarbon receptor (AHR). Binding of TCDD to the AHR leads to changes in transcription of numerous genes. Studies evaluating the transcriptional changes brought on by TCDD may provide valuable insight into the role of the AHR in human health and disease. We therefore compiled a collection of transcriptomic datasets that can be used to aid the scientific community in better understanding the transcriptional effects of ligand-activated AHR. Results Specifically, we have created a datasets package – TCDD.Transcriptomics – for the R statistical environment, consisting of 63 unique experiments comprising 377 samples, including various combinations of 3 species (human derived cell lines, mouse and rat), 4 tissue types (liver, kidney, white adipose tissue and hypothalamus) and a wide range of TCDD exposure times and doses. These datasets have been fully standardized using consistent preprocessing and annotation packages (available as of September 14, 2015). To demonstrate the utility of this R package, a subset of “AHR-core” genes were evaluated across the included datasets. Ahrr, Nqo1 and members of the Cyp family were significantly induced following exposure to TCDD across the studies as expected while Aldh3a1 was induced specifically in rat liver. Inmt was altered only in liver tissue and primarily by rat-AHR. Conclusions Analysis of the “AHR-core” genes demonstrates a continued need for studies surrounding the impact of AHR-activity on the transcriptome; genes believed to be consistently regulated by ligand-activated AHR show surprisingly little overlap across species and tissues. Until now, a comprehensive assessment of the transcriptome across these studies was challenging due to differences in array platforms, processing methods and annotation versions. We believe that this package, which is freely available for download (http://labs.oicr.on.ca/boutros-lab/tcdd-transcriptomics) will prove to be a highly beneficial resource to the scientific community evaluating the effects of TCDD exposure as well as the variety of functions of the AHR. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3446-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Stephenie D Prokopec
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Kathleen E Houlahan
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Ren X Sun
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada.,Department of Pharmacology & Toxicology, University of Toronto, Toronto, Canada
| | - John D Watson
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Cindy Q Yao
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Jamie Lee
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Christine P'ng
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Renee Pang
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Alexander H Wu
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Lauren C Chong
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Ashley B Smith
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Nicholas J Harding
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Ivy D Moffat
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, Canada
| | - Jere Lindén
- Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Sanna Lensu
- Department of Biology of Physical Activity, University of Jyväskylä, Jyväskylä, Finland.,Department of Environmental Health, National Institute for Health and Welfare, Kuopio, Finland
| | - Allan B Okey
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, Canada
| | - Raimo Pohjanvirta
- Laboratory of Toxicology, National Institute for Health and Welfare, Kuopio, Finland.,Department of Food Hygiene and Environmental Health, University of Helsinki, Helsinki, Finland
| | - Paul C Boutros
- Informatics and Bio-computing Program, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada. .,Department of Pharmacology & Toxicology, University of Toronto, Toronto, Canada. .,Department of Medical Biophysics, University of Toronto, Toronto, Canada.
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16
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Wimmerová S, van den Berg M, Chovancová J, Patayová H, Jusko TA, van Duursen MBM, Palkovičová Murínová Ľ, Canton RF, van Ede KI, Trnovec T. Relative effect potency estimates of dioxin-like activity for dioxins, furans, and dioxin-like PCBs in adults based on cytochrome P450 1A1 and 1B1 gene expression in blood. ENVIRONMENT INTERNATIONAL 2016; 96:24-33. [PMID: 27588699 PMCID: PMC6047354 DOI: 10.1016/j.envint.2016.08.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 08/22/2016] [Accepted: 08/22/2016] [Indexed: 05/04/2023]
Abstract
BACKGROUND In the risk assessment of PCDDs, PCDFs, and dioxin-like (DL) PCBs, regulatory authorities support the use of the toxic equivalency factor (TEF)-scheme derived from a heterogeneous data set of the relative effect potency (REPs) estimates. OBJECTIVES We sought to determine REPs for dioxin-like compounds (DLCs) using expression of cytochrome P450 (CYP) 1A1 and 1B1 mRNA in human peripheral blood mononuclear cells representing two different pathways. METHODS We used a sex and age adjusted regression-based approach comparing the strength of association between each DLC and the cytochrome P450 (CYP) 1A1 and 1B1 mRNA expression in 320 adults residing in an organochlorine-polluted area of eastern Slovakia. RESULTS We calculated REPs based on CYP1A1 expression for 4 PCDDs, 8 PCDFs, and 1 PCB congener, and based on CYP1B1 expression for 5 PCDFs and 11 PCB congeners. REPs from CYP1A1 correlated with REPs previously derived from thyroid volume (ρ=0.85; p<0.001) and serum FT4 (ρ=0.77; p=0.009). The 13 log REPs from CYP1A1 correlated with log WHO-TEFs (r=0.63; p=0.015) and 11 log PCB REPs with PCB consensus toxicity factors (CTFs) for compounds with WHO-TEFs (r=0.80; p=0.003). The complete set of derived 56 log REPs correlated with the log CTFs (r=0.77; p=0.001) and log WHO-TEFs (r=0.81; p<0.001). CONCLUSIONS REPs calculated from thyroid and cytochrome P450 endpoints realistically reflect human exposure scenarios because they are based on human chronic and low-dose exposures. While the CYP 1A1 seems more suitable for toxicity evaluation of PCDD/Fs, the CYP 1B1 is more apt for PCDFs and PCBs and reflects different pathways.
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Affiliation(s)
- Soňa Wimmerová
- Slovak Medical University, Limbová 14, 83303 Bratislava, Slovakia.
| | - Martin van den Berg
- Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.176, 3508, TD, Utrecht, The Netherlands.
| | - Jana Chovancová
- Slovak Medical University, Limbová 14, 83303 Bratislava, Slovakia.
| | | | - Todd A Jusko
- Departments of Public Health Sciences and Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
| | - Majorie B M van Duursen
- Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.176, 3508, TD, Utrecht, The Netherlands.
| | | | - Rocio F Canton
- Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.176, 3508, TD, Utrecht, The Netherlands.
| | - Karin I van Ede
- Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.176, 3508, TD, Utrecht, The Netherlands.
| | - Tomáš Trnovec
- Slovak Medical University, Limbová 14, 83303 Bratislava, Slovakia.
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17
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van Ede KI, van Duursen MBM, van den Berg M. Evaluation of relative effect potencies (REPs) for dioxin-like compounds to derive systemic or human-specific TEFs to improve human risk assessment. Arch Toxicol 2016; 90:1293-305. [PMID: 27161441 PMCID: PMC4873528 DOI: 10.1007/s00204-016-1724-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 04/21/2016] [Indexed: 01/20/2023]
Abstract
Toxic equivalency factors (TEFs) are generally applied for estimating human risk of dioxins and dioxin-like compounds using systemic (e.g., blood) levels, even though these TEFs are established based on intake doses in rodent studies. This review shows that systemic relative effect potencies (REPs) can deviate substantially from intake REPs, but are similar to in vitro-derived REPs. Interestingly, the in vitro REPs for 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (HpCDD) and 2,3,4,7,8-pentachlorodibenzofuran (4-PeCDF) are up to one order of magnitude higher than their in vivo REPs and WHO-TEFs, based on oral intake. In addition, clear species-differences in in vitro REPs were apparent for some congeners. Especially the human-derived REP for polychlorinated biphenyl 126 is one to two orders of magnitude lower than rodent REPs and its current WHO-TEF. Next, suggested adapted systemic or human-specific TEFs for these congeners were applied to calculate changes in systemic TEQ concentrations in studies from the USA, Germany and Japan and compared with either the JECFA TDI or USEPA RfD of TCDD. Overall, the effect of such TEF changes for these three congeners on total TEQ roughly balances each other out in the general population. However, results may be different for situations in which a specific group of congeners dominates. For those congeners that show a distinct deviation between either intake and systemic REPs or between rodent- and human-based in vitro REPs, we propose that especially REPs derived from human-based in vitro models are weighted more heavily in establishing systemic or human-specific TEF values to improve human health risk assessment.
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Affiliation(s)
- Karin I van Ede
- Division of Toxicology and Veterinary Pharmacology, Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.177, NL-3508 TD, Utrecht, The Netherlands.
| | - Majorie B M van Duursen
- Division of Toxicology and Veterinary Pharmacology, Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.177, NL-3508 TD, Utrecht, The Netherlands
| | - Martin van den Berg
- Division of Toxicology and Veterinary Pharmacology, Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.177, NL-3508 TD, Utrecht, The Netherlands
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18
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Watson JD, Prokopec SD, Smith AB, Okey AB, Pohjanvirta R, Boutros PC. 2,3,7,8 Tetrachlorodibenzo-p-dioxin-induced RNA abundance changes identify Ackr3, Col18a1, Cyb5a and Glud1 as candidate mediators of toxicity. Arch Toxicol 2016; 91:325-338. [PMID: 27136898 PMCID: PMC5225275 DOI: 10.1007/s00204-016-1720-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 04/20/2016] [Indexed: 12/11/2022]
Abstract
2,3,7,8 Tetrachlorodibenzo-p-dioxin (TCDD) is an aromatic, long-lived environmental contaminant. While the pathogenesis of TCDD-induced toxicity is poorly understood, it has been shown that the aryl hydrocarbon receptor (AHR) is required. However, the specific transcriptomic changes that lead to toxic outcomes have not yet been identified. We previously identified a panel of 33 genes that respond to TCDD treatment in two TCDD-sensitive rodent species. To identify genes involved in the onset of hepatic toxicity, we explored 25 of these in-depth using liver from two rat strains: the TCDD-resistant Han/Wistar (H/W) and the TCDD-sensitive Long–Evans (L–E). Time course and dose–response analyses of mRNA abundance following TCDD insult indicate that eight genes are similarly regulated in livers of both strains of rat, suggesting that they are not central to the severe L–E-specific TCDD-induced toxicities. The remaining 17 genes exhibited various divergent mRNA abundances between L–E and H/W strains after TCDD treatment. Several genes displayed a biphasic response where the initial response to TCDD treatment was followed by a secondary response, usually of larger magnitude in L–E liver. This secondary response was most often an exaggeration of the original TCDD-induced response. Only cytochrome b5 type A (microsomal) (Cyb5a) had equivalent TCDD sensitivity to the prototypic AHR-responsive cytochrome P450, family 1, subfamily a, polypeptide 1 (Cyp1a1), while six genes were less sensitive. Four genes showed an early inter-strain difference that was sustained throughout most of the time course (atypical chemokine receptor 3 (Ackr3), collagen, type XVIII, alpha 1 (Col18a1), Cyb5a and glutamate dehydrogenase 1 (Glud1)), and of those genes examined in this study, are most likely to represent genes involved in the pathogenesis of TCDD-induced hepatotoxicity in L–E rats.
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Affiliation(s)
- John D Watson
- Informatics and Bio-computing Program, MaRS Centre, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Stephenie D Prokopec
- Informatics and Bio-computing Program, MaRS Centre, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Ashley B Smith
- Informatics and Bio-computing Program, MaRS Centre, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada
| | - Allan B Okey
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Canada
| | - Raimo Pohjanvirta
- Laboratory of Toxicology, National Institute for Health and Welfare, Kuopio, Finland.,Department of Food Hygiene and Environmental Health, University of Helsinki, Helsinki, Finland
| | - Paul C Boutros
- Informatics and Bio-computing Program, MaRS Centre, Ontario Institute for Cancer Research, 661 University Avenue, Suite 510, Toronto, ON, M5G 0A3, Canada. .,Department of Pharmacology and Toxicology, University of Toronto, Toronto, Canada. .,Department of Medical Biophysics, University of Toronto, Toronto, Canada.
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19
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Attignon EA, Leblanc AF, Le-Grand B, Duval C, Aggerbeck M, Rouach H, Blanc EB. Novel roles for AhR and ARNT in the regulation of alcohol dehydrogenases in human hepatic cells. Arch Toxicol 2016; 91:313-324. [PMID: 27055685 DOI: 10.1007/s00204-016-1700-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 03/21/2016] [Indexed: 12/13/2022]
Abstract
The mechanisms by which pollutants participate in the development of diverse pathologies are not completely understood. The pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) activates the AhR (aryl hydrocarbon receptor) signaling pathway. We previously showed that TCDD (25 nM, 30 h) decreased the expression of several alcohol metabolism enzymes (cytochrome P450 2E1, alcohol dehydrogenases ADH1, 4 and 6) in differentiated human hepatic cells (HepaRG). Here, we show that, as rapidly as 8 h after treatment (25 nM TCDD) ADH expression decreased 40 % (p < 0.05). ADH1 and 4 protein levels decreased 40 and 27 %, respectively (p < 0.05), after 72 h (25 nM TCDD). The protein half-lives were not modified by TCDD which suggests transcriptional regulation of expression. The AhR antagonist CH-223191 or AhR siRNA reduced the inhibitory effect of 25 nM TCDD on ADH1A, 4 and 6 expression 50-100 % (p < 0.05). The genomic pathway (via the AhR/ARNT complex) and not the non-genomic pathway involving c-SRC mediated these effects. Other AhR ligands (3-methylcholanthrene and PCB 126) decreased ADH1B, 4 and 6 mRNAs by more than 78 and 55 %, respectively (p < 0.01). TCDD also regulated the expression of ADH4 in the HepG2 human hepatic cell line, in primary human hepatocytes and in C57BL/6J mouse liver. In conclusion, activation of the AhR/ARNT signaling pathway by AhR ligands represents a novel mechanism for regulating the expression of ADHs. These effects may be implicated in the toxicity of AhR ligands as well as in the alteration of ethanol or retinol metabolism and may be associated further with higher risk of liver diseases or/and alcohol abuse disorders.
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Affiliation(s)
- Eléonore A Attignon
- INSERM, UMR-S 1124, Toxicologie Pharmacologie et Signalisation Cellulaire, 45 rue des Saints Pères, F-75006, Paris, France.,ComUE Sorbonne Paris Cité, Université Paris Descartes, CICB-Paris, 45 rue des Saints Pères, F-75006, Paris, France
| | - Alix F Leblanc
- INSERM, UMR-S 1124, Toxicologie Pharmacologie et Signalisation Cellulaire, 45 rue des Saints Pères, F-75006, Paris, France.,ComUE Sorbonne Paris Cité, Université Paris Descartes, CICB-Paris, 45 rue des Saints Pères, F-75006, Paris, France
| | - Béatrice Le-Grand
- INSERM, UMR-S 1124, Toxicologie Pharmacologie et Signalisation Cellulaire, 45 rue des Saints Pères, F-75006, Paris, France.,ComUE Sorbonne Paris Cité, Université Paris Descartes, CICB-Paris, 45 rue des Saints Pères, F-75006, Paris, France
| | - Caroline Duval
- INSERM, UMR-S 1124, Toxicologie Pharmacologie et Signalisation Cellulaire, 45 rue des Saints Pères, F-75006, Paris, France.,ComUE Sorbonne Paris Cité, Université Paris Descartes, CICB-Paris, 45 rue des Saints Pères, F-75006, Paris, France
| | - Martine Aggerbeck
- INSERM, UMR-S 1124, Toxicologie Pharmacologie et Signalisation Cellulaire, 45 rue des Saints Pères, F-75006, Paris, France.,ComUE Sorbonne Paris Cité, Université Paris Descartes, CICB-Paris, 45 rue des Saints Pères, F-75006, Paris, France
| | - Hélène Rouach
- INSERM, UMR-S 1124, Toxicologie Pharmacologie et Signalisation Cellulaire, 45 rue des Saints Pères, F-75006, Paris, France.,ComUE Sorbonne Paris Cité, Université Paris Descartes, CICB-Paris, 45 rue des Saints Pères, F-75006, Paris, France
| | - Etienne B Blanc
- INSERM, UMR-S 1124, Toxicologie Pharmacologie et Signalisation Cellulaire, 45 rue des Saints Pères, F-75006, Paris, France. .,ComUE Sorbonne Paris Cité, Université Paris Descartes, CICB-Paris, 45 rue des Saints Pères, F-75006, Paris, France.
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20
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Zhang J, Zhang X, Xia P, Zhang R, Wu Y, Xia J, Su G, Zhang J, Giesy JP, Wang Z, Villeneuve DL, Yu H. Activation of AhR-mediated toxicity pathway by emerging pollutants polychlorinated diphenyl sulfides. CHEMOSPHERE 2016; 144:1754-1762. [PMID: 26524144 DOI: 10.1016/j.chemosphere.2015.09.107] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 09/29/2015] [Accepted: 09/29/2015] [Indexed: 06/05/2023]
Abstract
Polychlorinated diphenyl sulfides (PCDPSs) are a group of environmental pollutants for which limited toxicological information is available. This study tested the hypothesis that PCDPSs could activate the mammalian aryl hydrocarbon receptor (AhR) mediated toxicity pathways. Eighteen PCDPSs were tested in the H4IIE-luc transactivation assay, with 13/18 causing concentration-dependent AhR activation. Potencies of several congeners were similar to those of mono-ortho substituted polychlorinated biphenyls. A RNA sequencing (RNA-seq)-based transcriptomic analysis was performed on H4IIE cells treated with two PCDPS congeners, 2,2',3,3',4,5,6-hepta-CDPS, and 2,4,4',5-tetra-CDPS. Results of RNA-seq revealed a remarkable modulation on a relatively short gene list by exposure to the tested concentrations of PCDPSs, among which, Cyp1 responded with the greatest fold up-regulation. Both the identities of the modulated transcripts and the associated pathways were consistent with targets and pathways known to be modulated by other types of AhR agonists and there was little evidence for significant off-target effects within the cellular context of the H4IIE bioassay. The results suggest AhR activation as a toxicologically relevant mode of action for PCDPSs suggests the utility of AhR-related toxicity pathways for predicting potential hazards associated with PCDPS exposure in mammals and potentially other vertebrates.
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Affiliation(s)
- Junjiang Zhang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Xiaowei Zhang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China.
| | - Pu Xia
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Rui Zhang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Yang Wu
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Jie Xia
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Guanyong Su
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Jiamin Zhang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - John P Giesy
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China; Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; Department of Zoology, and Center for Integrative Toxicology, Michigan State University, East Lansing, MI, USA; School of Biological Sciences, University of Hong Kong, Hong Kong, China; Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | - Zunyao Wang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Daniel L Villeneuve
- United States Environmental Protection Agency, Mid-Continent Ecology Division, Duluth, MN, USA
| | - Hongxia Yu
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
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21
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Ambolet-Camoit A, Ottolenghi C, Leblanc A, Kim MJ, Letourneur F, Jacques S, Cagnard N, Guguen-Guillouzo C, Barouki R, Aggerbeck M. Two persistent organic pollutants which act through different xenosensors (alpha-endosulfan and 2,3,7,8 tetrachlorodibenzo-p-dioxin) interact in a mixture and downregulate multiple genes involved in human hepatocyte lipid and glucose metabolism. Biochimie 2015; 116:79-91. [PMID: 26159488 DOI: 10.1016/j.biochi.2015.07.003] [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: 06/30/2015] [Accepted: 07/03/2015] [Indexed: 11/16/2022]
Abstract
Individuals, typically, are exposed to mixtures of environmental xenobiotics affecting multiple organs and acting through different xenosensors and pathways in species and cell-type specific manners. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and α-endosulfan are Persistent Organic Pollutants (POPs) and endocrine disruptors which act through different xenosensors and accumulate in the liver. Our objective in this HEALS study was to investigate the effects of the mixture of these POPs on gene expression in a human-derived hepatocyte cell line, HepaRG. We found that, in spite of having largely uncorrelated effects, TCDD and α-endosulfan, when mixed, alter the expression of genes. The combined effects of the mixture of the POPs significantly altered the expression of 100 genes (42 up- and 58 down-regulated) whereas the same concentration of either POP alone did not alter significantly the expression of these genes. For 32 other genes, selective inhibitory crosstalk between TCDD and α-endosulfan was observed. One of the POPs inhibited the effect, on gene expression, of the other in the mixture although, when used alone, that POP did not affect expression. The expression of another 82 genes was significantly altered (up- or down-regulated) by a single POP. The addition of the second POP either increased, in the same direction, the effect on gene expression or had no further effect. At low concentrations (0.2 nM TCDD and 1 μM α-endosulfan), the POPs still had significant effects and the levels of expression of the corresponding proteins were found to be affected for some genes. Particularly striking was the 80-90% inhibition, by the mixture, of the expression of a number of genes of several hepatic intermediary metabolic pathways (glycerolipid metabolism, FXR/RXR activation, glycolysis/gluconeogenesis, retinoid and bile acid biosynthesis), whereas each pollutant alone had only a moderate effect.
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Affiliation(s)
- Ariane Ambolet-Camoit
- Inserm UMR-S 1124, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Chris Ottolenghi
- Inserm UMR-S 1124, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France; APHP, Hôpital Necker Enfants Malades, Service de Biochimie Métabolique, Paris, France
| | - Alix Leblanc
- Inserm UMR-S 1124, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Min Ji Kim
- Inserm UMR-S 1124, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Franck Letourneur
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Plateforme de Génomique, Institut Cochin, Paris, France
| | - Sébastien Jacques
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Plateforme de Génomique, Institut Cochin, Paris, France
| | - Nicolas Cagnard
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Plateforme de Génomique, Institut Cochin, Paris, France
| | | | - Robert Barouki
- Inserm UMR-S 1124, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France; APHP, Hôpital Necker Enfants Malades, Service de Biochimie Métabolique, Paris, France
| | - Martine Aggerbeck
- Inserm UMR-S 1124, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
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22
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Becker RA, Patlewicz G, Simon TW, Rowlands JC, Budinsky RA. The adverse outcome pathway for rodent liver tumor promotion by sustained activation of the aryl hydrocarbon receptor. Regul Toxicol Pharmacol 2015; 73:172-90. [PMID: 26145830 DOI: 10.1016/j.yrtph.2015.06.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 06/19/2015] [Accepted: 06/22/2015] [Indexed: 12/29/2022]
Abstract
An Adverse Outcome Pathway (AOP) represents the existing knowledge of a biological pathway leading from initial molecular interactions of a toxicant and progressing through a series of key events (KEs), culminating with an apical adverse outcome (AO) that has to be of regulatory relevance. An AOP based on the mode of action (MOA) of rodent liver tumor promotion by dioxin-like compounds (DLCs) has been developed and the weight of evidence (WoE) of key event relationships (KERs) evaluated using evolved Bradford Hill considerations. Dioxins and DLCs are potent aryl hydrocarbon receptor (AHR) ligands that cause a range of species-specific adverse outcomes. The occurrence of KEs is necessary for inducing downstream biological responses and KEs may occur at the molecular, cellular, tissue and organ levels. The common convention is that an AOP begins with the toxicant interaction with a biological response element; for this AOP, this initial event is binding of a DLC ligand to the AHR. Data from mechanistic studies, lifetime bioassays and approximately thirty initiation-promotion studies have established dioxin and DLCs as rat liver tumor promoters. Such studies clearly show that sustained AHR activation, weeks or months in duration, is necessary to induce rodent liver tumor promotion--hence, sustained AHR activation is deemed the molecular initiating event (MIE). After this MIE, subsequent KEs are 1) changes in cellular growth homeostasis likely associated with expression changes in a number of genes and observed as development of hepatic foci and decreases in apoptosis within foci; 2) extensive liver toxicity observed as the constellation of effects called toxic hepatopathy; 3) cellular proliferation and hyperplasia in several hepatic cell types. This progression of KEs culminates in the AO, the development of hepatocellular adenomas and carcinomas and cholangiolar carcinomas. A rich data set provides both qualitative and quantitative knowledge of the progression of this AOP through KEs and the KERs. Thus, the WoE for this AOP is judged to be strong. Species-specific effects of dioxins and DLCs are well known--humans are less responsive than rodents and rodent species differ in sensitivity between strains. Consequently, application of this AOP to evaluate potential human health risks must take these differences into account.
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Affiliation(s)
- Richard A Becker
- Regulatory and Technical Affairs Department, American Chemistry Council (ACC), Washington, DC 20002, USA.
| | - Grace Patlewicz
- DuPont Haskell Global Centers for Health and Environmental Sciences, Newark, DE 19711, USA
| | - Ted W Simon
- Ted Simon LLC, 4184 Johnston Road, Winston, GA 30187, USA
| | - J Craig Rowlands
- The Dow Chemical Company, Toxicology & Environmental Research & Consulting, 1803 Building Washington Street, Midland, MI 48674, USA
| | - Robert A Budinsky
- The Dow Chemical Company, Toxicology & Environmental Research & Consulting, 1803 Building Washington Street, Midland, MI 48674, USA
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23
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Wahlang B, Falkner KC, Cave MC, Prough RA. Role of Cytochrome P450 Monooxygenase in Carcinogen and Chemotherapeutic Drug Metabolism. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2015; 74:1-33. [PMID: 26233902 DOI: 10.1016/bs.apha.2015.04.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The purpose of this chapter is to provide insight into which human cytochromes P450 (CYPs) may be involved in metabolism of chemical carcinogens and anticancer drugs. A historical overview of this field and the development of literature using relevant animal models and expressed human CYPs have provided information about which specific CYPs may be involved in carcinogen metabolism. Definition of the biochemical properties of CYP activity came from several groups who studied the reaction stoichiometry of butter yellow and benzo[α]pyrene, including their role in induction of these enzyme systems. This chapter will list as much as is known about the human CYPs involved in carcinogen and anticancer drug metabolism, as well as summarize studies with rodent CYPs. A review of three major classes of anticancer drugs and their metabolism in humans is covered for cyclophosphamide, procarbazine, and anthracycline antibiotics, cancer chemotherapeutic compounds extensively metabolized by CYPs. The emerging information about human CYP gene polymorphisms as well as other enzymes involved in foreign compound metabolism provides considerable information about how these genetic variants affect carcinogen and anticancer drug metabolism. With information available from individual's genomic sequences, consideration of populations who may be at risk due to environmental exposure to carcinogens or how to optimize their cancer therapy regimens to enhance efficacy of the anticancer drugs appears to be an important field of study to benefit individuals in the future.
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Affiliation(s)
- B Wahlang
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, University of Louisville, Louisville, Kentucky, USA
| | - K Cameron Falkner
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, University of Louisville, Louisville, Kentucky, USA
| | - Matt C Cave
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, University of Louisville, Louisville, Kentucky, USA; Department of Biochemistry & Molecular Biology, University of Louisville, Louisville, Kentucky, USA
| | - Russell A Prough
- Department of Biochemistry & Molecular Biology, University of Louisville, Louisville, Kentucky, USA.
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Glass K, Quackenbush J, Spentzos D, Haibe-Kains B, Yuan GC. A network model for angiogenesis in ovarian cancer. BMC Bioinformatics 2015; 16:115. [PMID: 25888305 PMCID: PMC4408593 DOI: 10.1186/s12859-015-0551-y] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 03/25/2015] [Indexed: 12/31/2022] Open
Abstract
Background We recently identified two robust ovarian cancer subtypes, defined by the expression of genes involved in angiogenesis, with significant differences in clinical outcome. To identify potential regulatory mechanisms that distinguish the subtypes we applied PANDA, a method that uses an integrative approach to model information flow in gene regulatory networks. Results We find distinct differences between networks that are active in the angiogenic and non-angiogenic subtypes, largely defined by a set of key transcription factors that, although previously reported to play a role in angiogenesis, are not strongly differentially-expressed between the subtypes. Our network analysis indicates that these factors are involved in the activation (or repression) of different genes in the two subtypes, resulting in differential expression of their network targets. Mechanisms mediating differences between subtypes include a previously unrecognized pro-angiogenic role for increased genome-wide DNA methylation and complex patterns of combinatorial regulation. Conclusions The models we develop require a shift in our interpretation of the driving factors in biological networks away from the genes themselves and toward their interactions. The observed regulatory changes between subtypes suggest therapeutic interventions that may help in the treatment of ovarian cancer. Electronic supplementary material The online version of this article (doi:10.1186/s12859-015-0551-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kimberly Glass
- Dana-Farber Cancer Institute, Boston, MA, USA. .,Harvard School of Public Health, Boston, MA, USA. .,Brigham and Women's Hospital, Boston, MA, USA.
| | - John Quackenbush
- Dana-Farber Cancer Institute, Boston, MA, USA. .,Harvard School of Public Health, Boston, MA, USA.
| | - Dimitrios Spentzos
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
| | - Benjamin Haibe-Kains
- Princess Margaret Cancer Center, University Health Network, Toronto, ON, M5G 2M9, Canada.
| | - Guo-Cheng Yuan
- Dana-Farber Cancer Institute, Boston, MA, USA. .,Harvard School of Public Health, Boston, MA, USA.
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25
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Finkbeiner S, Frumkin M, Kassner PD. Cell-based screening: extracting meaning from complex data. Neuron 2015; 86:160-74. [PMID: 25856492 PMCID: PMC4457442 DOI: 10.1016/j.neuron.2015.02.023] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 09/23/2014] [Accepted: 01/22/2015] [Indexed: 01/23/2023]
Abstract
Unbiased discovery approaches have the potential to uncover neurobiological insights into CNS disease and lead to the development of therapies. Here, we review lessons learned from imaging-based screening approaches and recent advances in these areas, including powerful new computational tools to synthesize complex data into more useful knowledge that can reliably guide future research and development.
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Affiliation(s)
- Steven Finkbeiner
- Director of the Taube/Koret Center for Neurodegenerative Disease and the Hellman Family Foundation Program in Alzheimer's Disease Research, Gladstone Institute of Neurological Disease, San Francisco, CA 94158, USA; Departments of Neurology and Physiology, University of California, San Francisco, San Francisco, CA 94143, USA.
| | - Michael Frumkin
- Director of Engineering, Research, Google, Inc., 1600 Amphitheatre Parkway, Mountain View, CA 94043, USA
| | - Paul D Kassner
- Director of Research, Amgen, Inc., 1120 Veterans Boulevard South, San Francisco, CA 94080, USA
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26
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Ghorbanzadeh M, van Ede KI, Larsson M, van Duursen MBM, Poellinger L, Lücke-Johansson S, Machala M, Pěnčíková K, Vondráček J, van den Berg M, Denison MS, Ringsted T, Andersson PL. In Vitro and in Silico Derived Relative Effect Potencies of Ah-Receptor-Mediated Effects by PCDD/Fs and PCBs in Rat, Mouse, and Guinea Pig CALUX Cell Lines. Chem Res Toxicol 2014; 27:1120-32. [DOI: 10.1021/tx5001255] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Karin I. van Ede
- Endocrine Toxicology Group, Institute for Risk Assessment
Sciences, Utrecht University, P.O. Box 80177, NL-3508 TD Utrecht, The Netherlands
| | - Malin Larsson
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | - Majorie B. M. van Duursen
- Endocrine Toxicology Group, Institute for Risk Assessment
Sciences, Utrecht University, P.O. Box 80177, NL-3508 TD Utrecht, The Netherlands
| | - Lorenz Poellinger
- Department
of Cell and Molecular Biology, Karolinska Institute, SE-171 77 Stockholm, Sweden
| | - Sandra Lücke-Johansson
- Department
of Cell and Molecular Biology, Karolinska Institute, SE-171 77 Stockholm, Sweden
| | - Miroslav Machala
- Department of Chemistry
and Toxicology, Veterinary Research Institute, 621 32 Brno, Czech Republic
| | - Kateřina Pěnčíková
- Department of Chemistry
and Toxicology, Veterinary Research Institute, 621 32 Brno, Czech Republic
| | - Jan Vondráček
- Department of Chemistry
and Toxicology, Veterinary Research Institute, 621 32 Brno, Czech Republic
| | - Martin van den Berg
- Endocrine Toxicology Group, Institute for Risk Assessment
Sciences, Utrecht University, P.O. Box 80177, NL-3508 TD Utrecht, The Netherlands
| | - Michael S. Denison
- Department of Environmental Toxicology, University of California, Davis, California 95616, United States
| | - Tine Ringsted
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
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27
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van Ede KI, Gaisch KPJ, van den Berg M, van Duursen MBM. Differential relative effect potencies of some dioxin-like compounds in human peripheral blood lymphocytes and murine splenic cells. Toxicol Lett 2014; 226:43-52. [PMID: 24472611 DOI: 10.1016/j.toxlet.2014.01.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 01/16/2014] [Accepted: 01/17/2014] [Indexed: 11/29/2022]
Abstract
Human risk assessment for dioxin-like compounds is typically based on the concentration measured in blood serum multiplied by their assigned toxic equivalency factor (TEF). Consequently, the actual value of the TEF is very important for accurate human risk assessment. In this study we investigated the effect potencies of three polychlorinated dibenzo-p-dioxins (PCDDs), six polychlorinated dibenzofurans (PCDFs) and 10 polychlorinated biphenyls (PCBs) relative to the reference congener 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD) in in vitro exposed primary human peripheral blood lymphocytes (PBLs) and mouse splenic cells. REPs were determined based on cytochrome P450 (CYP) 1A1, 1B1 and aryl hydrocarbon receptor repressor (AhRR) gene expression as well as CYP1A1 activity in human PBLs and Cyp1a1 gene expression in murine splenic cells. Estimated median human REPs for 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (1234678-HpCDD), 2,3,4,7,8,-pentachlorodibenzofuran (23478-PeCDF), 1,2,3,4,7,8-hexachlorodibenzofuran (123478-HxCDF) and 1,2,3,4,7,8,9-heptachlorodibenzofuran (1234789-HpCDF) were with 0.1, 1.1, 1 and 0.09, respectively, significantly higher compared to those estimated for mouse with REPs of 0.05, 0.45, 0.09 and 0.04, respectively. Opposite to these results, the estimated median human REP of 3,3',4,4',5-pentachlorobiphenyl (PCB 126), was with 0.001 30-fold lower compared to the mouse REP of 0.03. Furthermore, human REPs for 1234678-HpCDD, 23478-PeCDF, 123478-HxCDF, 1234789-HpCDF and PCB 126 were all outside the ± half log uncertainty range that is taken into account in the WHO-assigned TEFs. Together, these data show congener- and species-specific differences in REPs for some, but not all dioxin-like congeners tested. This suggests that, more emphasis should be placed on human-tissue derived REPs in the establishment of a TEF for human risk assessment.
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Affiliation(s)
- Karin I van Ede
- Institute for Risk Assessment Sciences, Utrecht University, Yalelaan 104, 3584 CM Utrecht, The Netherlands.
| | - Konrad P J Gaisch
- Institute for Risk Assessment Sciences, Utrecht University, Yalelaan 104, 3584 CM Utrecht, The Netherlands.
| | - Martin van den Berg
- Institute for Risk Assessment Sciences, Utrecht University, Yalelaan 104, 3584 CM Utrecht, The Netherlands.
| | - Majorie B M van Duursen
- Institute for Risk Assessment Sciences, Utrecht University, Yalelaan 104, 3584 CM Utrecht, The Netherlands.
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Budinsky RA, Schrenk D, Simon T, Van den Berg M, Reichard JF, Silkworth JB, Aylward LL, Brix A, Gasiewicz T, Kaminski N, Perdew G, Starr TB, Walker NJ, Rowlands JC. Mode of action and dose–response framework analysis for receptor-mediated toxicity: The aryl hydrocarbon receptor as a case study. Crit Rev Toxicol 2013; 44:83-119. [DOI: 10.3109/10408444.2013.835787] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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29
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Rowlands JC, Budinsky R, Gollapudi B, Black MB, Wolfinger RD, Cukovic D, Dombkowski A, Thompson CM, Urban JD, Thomas RS. A genomics-based analysis of relative potencies of dioxin-like compounds in primary rat hepatocytes. Toxicol Sci 2013; 136:595-604. [PMID: 24046277 DOI: 10.1093/toxsci/kft203] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Toxic equivalency factors (TEFs) for dioxin-like compounds are largely based on relative potency (REP) values derived from biochemical endpoints such as enzyme activity. As of yet, REPs based on gene expression changes have not been accounted for in the TEF values. In this study, primary rat hepatocytes were treated for 24h with 11 concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,4,7,8-pentachlorodibenzofuran (4-PeCDF), or 2,3,7,8-tetrachlorodibenzofuran (TCDF) ranging from 0.00001 to 100 nM. Differential changes in gene expression were analyzed using analysis of variance to assess the relative contributions of concentration, congener, and the interaction between concentration and congener for each gene. A total of 3283 genes showed significant changes with concentration (false discovery rate < .05 and fold-change ± 1.5 in at least 1 concentration for 1 congener). Among these genes, 399 were significant for both concentration and congener effects indicating parallel concentration-response curves with significant differences in potency. Only 8 genes showed a significant concentration and congener interaction term indicating a minority of genes show nonparallel dose-response curves among the 3 congeners. Benchmark dose (BMD) modeling was used to derive BMD values for induced individual genes and signaling pathways. The REP values for 4-PeCDF and TCDF were generally 3- to 5-fold lower than the World Health Organization (WHO) TEF values on both a gene and pathway basis. These findings suggest that the WHO TEF values may possibly overpredict the potency of these polychlorinated dibenzofuran congeners and demonstrate the importance of identifying functional pathways relevant to the toxicological modes of action for establishing pertinent REPs.
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Affiliation(s)
- J Craig Rowlands
- * Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, Michigan 48674
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30
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Godoy P, Hewitt NJ, Albrecht U, Andersen ME, Ansari N, Bhattacharya S, Bode JG, Bolleyn J, Borner C, Böttger J, Braeuning A, Budinsky RA, Burkhardt B, Cameron NR, Camussi G, Cho CS, Choi YJ, Craig Rowlands J, Dahmen U, Damm G, Dirsch O, Donato MT, Dong J, Dooley S, Drasdo D, Eakins R, Ferreira KS, Fonsato V, Fraczek J, Gebhardt R, Gibson A, Glanemann M, Goldring CEP, Gómez-Lechón MJ, Groothuis GMM, Gustavsson L, Guyot C, Hallifax D, Hammad S, Hayward A, Häussinger D, Hellerbrand C, Hewitt P, Hoehme S, Holzhütter HG, Houston JB, Hrach J, Ito K, Jaeschke H, Keitel V, Kelm JM, Kevin Park B, Kordes C, Kullak-Ublick GA, LeCluyse EL, Lu P, Luebke-Wheeler J, Lutz A, Maltman DJ, Matz-Soja M, McMullen P, Merfort I, Messner S, Meyer C, Mwinyi J, Naisbitt DJ, Nussler AK, Olinga P, Pampaloni F, Pi J, Pluta L, Przyborski SA, Ramachandran A, Rogiers V, Rowe C, Schelcher C, Schmich K, Schwarz M, Singh B, Stelzer EHK, Stieger B, Stöber R, Sugiyama Y, Tetta C, Thasler WE, Vanhaecke T, Vinken M, Weiss TS, Widera A, Woods CG, Xu JJ, Yarborough KM, Hengstler JG. Recent advances in 2D and 3D in vitro systems using primary hepatocytes, alternative hepatocyte sources and non-parenchymal liver cells and their use in investigating mechanisms of hepatotoxicity, cell signaling and ADME. Arch Toxicol 2013; 87:1315-530. [PMID: 23974980 PMCID: PMC3753504 DOI: 10.1007/s00204-013-1078-5] [Citation(s) in RCA: 1051] [Impact Index Per Article: 95.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 05/06/2013] [Indexed: 12/15/2022]
Abstract
This review encompasses the most important advances in liver functions and hepatotoxicity and analyzes which mechanisms can be studied in vitro. In a complex architecture of nested, zonated lobules, the liver consists of approximately 80 % hepatocytes and 20 % non-parenchymal cells, the latter being involved in a secondary phase that may dramatically aggravate the initial damage. Hepatotoxicity, as well as hepatic metabolism, is controlled by a set of nuclear receptors (including PXR, CAR, HNF-4α, FXR, LXR, SHP, VDR and PPAR) and signaling pathways. When isolating liver cells, some pathways are activated, e.g., the RAS/MEK/ERK pathway, whereas others are silenced (e.g. HNF-4α), resulting in up- and downregulation of hundreds of genes. An understanding of these changes is crucial for a correct interpretation of in vitro data. The possibilities and limitations of the most useful liver in vitro systems are summarized, including three-dimensional culture techniques, co-cultures with non-parenchymal cells, hepatospheres, precision cut liver slices and the isolated perfused liver. Also discussed is how closely hepatoma, stem cell and iPS cell-derived hepatocyte-like-cells resemble real hepatocytes. Finally, a summary is given of the state of the art of liver in vitro and mathematical modeling systems that are currently used in the pharmaceutical industry with an emphasis on drug metabolism, prediction of clearance, drug interaction, transporter studies and hepatotoxicity. One key message is that despite our enthusiasm for in vitro systems, we must never lose sight of the in vivo situation. Although hepatocytes have been isolated for decades, the hunt for relevant alternative systems has only just begun.
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Affiliation(s)
- Patricio Godoy
- Leibniz Research Centre for Working Environment and Human Factors (IFADO), 44139 Dortmund, Germany
| | | | - Ute Albrecht
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Melvin E. Andersen
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Nariman Ansari
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany
| | - Sudin Bhattacharya
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Johannes Georg Bode
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Jennifer Bolleyn
- Department of Toxicology, Centre for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 1090 Brussels, Belgium
| | - Christoph Borner
- Institute of Molecular Medicine and Cell Research, University of Freiburg, Freiburg, Germany
| | - Jan Böttger
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Albert Braeuning
- Department of Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, Wilhelmstr. 56, 72074 Tübingen, Germany
| | - Robert A. Budinsky
- Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI USA
| | - Britta Burkhardt
- BG Trauma Center, Siegfried Weller Institut, Eberhard Karls University Tübingen, 72076 Tübingen, Germany
| | - Neil R. Cameron
- Department of Chemistry, Durham University, Durham, DH1 3LE UK
| | - Giovanni Camussi
- Department of Medical Sciences, University of Torino, 10126 Turin, Italy
| | - Chong-Su Cho
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 151-921 Korea
| | - Yun-Jaie Choi
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 151-921 Korea
| | - J. Craig Rowlands
- Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, MI USA
| | - Uta Dahmen
- Experimental Transplantation Surgery, Department of General Visceral, and Vascular Surgery, Friedrich-Schiller-University Jena, 07745 Jena, Germany
| | - Georg Damm
- Department of General-, Visceral- and Transplantation Surgery, Charité University Medicine Berlin, 13353 Berlin, Germany
| | - Olaf Dirsch
- Institute of Pathology, Friedrich-Schiller-University Jena, 07745 Jena, Germany
| | - María Teresa Donato
- Unidad de Hepatología Experimental, IIS Hospital La Fe Avda Campanar 21, 46009 Valencia, Spain
- CIBERehd, Fondo de Investigaciones Sanitarias, Barcelona, Spain
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad de Valencia, Valencia, Spain
| | - Jian Dong
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Steven Dooley
- Department of Medicine II, Section Molecular Hepatology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Dirk Drasdo
- Interdisciplinary Center for Bioinformatics (IZBI), University of Leipzig, 04107 Leipzig, Germany
- INRIA (French National Institute for Research in Computer Science and Control), Domaine de Voluceau-Rocquencourt, B.P. 105, 78153 Le Chesnay Cedex, France
- UPMC University of Paris 06, CNRS UMR 7598, Laboratoire Jacques-Louis Lions, 4, pl. Jussieu, 75252 Paris cedex 05, France
| | - Rowena Eakins
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Karine Sá Ferreira
- Institute of Molecular Medicine and Cell Research, University of Freiburg, Freiburg, Germany
- GRK 1104 From Cells to Organs, Molecular Mechanisms of Organogenesis, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Valentina Fonsato
- Department of Medical Sciences, University of Torino, 10126 Turin, Italy
| | - Joanna Fraczek
- Department of Toxicology, Centre for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 1090 Brussels, Belgium
| | - Rolf Gebhardt
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Andrew Gibson
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Matthias Glanemann
- Department of General-, Visceral- and Transplantation Surgery, Charité University Medicine Berlin, 13353 Berlin, Germany
| | - Chris E. P. Goldring
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - María José Gómez-Lechón
- Unidad de Hepatología Experimental, IIS Hospital La Fe Avda Campanar 21, 46009 Valencia, Spain
- CIBERehd, Fondo de Investigaciones Sanitarias, Barcelona, Spain
| | - Geny M. M. Groothuis
- Department of Pharmacy, Pharmacokinetics Toxicology and Targeting, University of Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Lena Gustavsson
- Department of Laboratory Medicine (Malmö), Center for Molecular Pathology, Lund University, Jan Waldenströms gata 59, 205 02 Malmö, Sweden
| | - Christelle Guyot
- Department of Clinical Pharmacology and Toxicology, University Hospital, 8091 Zurich, Switzerland
| | - David Hallifax
- Centre for Applied Pharmacokinetic Research (CAPKR), School of Pharmacy and Pharmaceutical Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT UK
| | - Seddik Hammad
- Department of Forensic Medicine and Veterinary Toxicology, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt
| | - Adam Hayward
- Biological and Biomedical Sciences, Durham University, Durham, DH13LE UK
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Claus Hellerbrand
- Department of Medicine I, University Hospital Regensburg, 93053 Regensburg, Germany
| | | | - Stefan Hoehme
- Interdisciplinary Center for Bioinformatics (IZBI), University of Leipzig, 04107 Leipzig, Germany
| | - Hermann-Georg Holzhütter
- Institut für Biochemie Abteilung Mathematische Systembiochemie, Universitätsmedizin Berlin (Charité), Charitéplatz 1, 10117 Berlin, Germany
| | - J. Brian Houston
- Centre for Applied Pharmacokinetic Research (CAPKR), School of Pharmacy and Pharmaceutical Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT UK
| | | | - Kiyomi Ito
- Research Institute of Pharmaceutical Sciences, Musashino University, 1-1-20 Shinmachi, Nishitokyo-shi, Tokyo, 202-8585 Japan
| | - Hartmut Jaeschke
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160 USA
| | - Verena Keitel
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | | | - B. Kevin Park
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Claus Kordes
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Gerd A. Kullak-Ublick
- Department of Clinical Pharmacology and Toxicology, University Hospital, 8091 Zurich, Switzerland
| | - Edward L. LeCluyse
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Peng Lu
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | | | - Anna Lutz
- Department of Pharmaceutical Biology and Biotechnology, University of Freiburg, Freiburg, Germany
| | - Daniel J. Maltman
- Reinnervate Limited, NETPark Incubator, Thomas Wright Way, Sedgefield, TS21 3FD UK
| | - Madlen Matz-Soja
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Patrick McMullen
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Irmgard Merfort
- Department of Pharmaceutical Biology and Biotechnology, University of Freiburg, Freiburg, Germany
| | | | - Christoph Meyer
- Department of Medicine II, Section Molecular Hepatology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Jessica Mwinyi
- Department of Clinical Pharmacology and Toxicology, University Hospital, 8091 Zurich, Switzerland
| | - Dean J. Naisbitt
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Andreas K. Nussler
- BG Trauma Center, Siegfried Weller Institut, Eberhard Karls University Tübingen, 72076 Tübingen, Germany
| | - Peter Olinga
- Division of Pharmaceutical Technology and Biopharmacy, Department of Pharmacy, University of Groningen, 9713 AV Groningen, The Netherlands
| | - Francesco Pampaloni
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany
| | - Jingbo Pi
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Linda Pluta
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | - Stefan A. Przyborski
- Reinnervate Limited, NETPark Incubator, Thomas Wright Way, Sedgefield, TS21 3FD UK
- Biological and Biomedical Sciences, Durham University, Durham, DH13LE UK
| | - Anup Ramachandran
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160 USA
| | - Vera Rogiers
- Department of Toxicology, Centre for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 1090 Brussels, Belgium
| | - Cliff Rowe
- Department of Molecular and Clinical Pharmacology, Centre for Drug Safety Science, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Celine Schelcher
- Department of Surgery, Liver Regeneration, Core Facility, Human in Vitro Models of the Liver, Ludwig Maximilians University of Munich, Munich, Germany
| | - Kathrin Schmich
- Department of Pharmaceutical Biology and Biotechnology, University of Freiburg, Freiburg, Germany
| | - Michael Schwarz
- Department of Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, Wilhelmstr. 56, 72074 Tübingen, Germany
| | - Bijay Singh
- Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, 151-921 Korea
| | - Ernst H. K. Stelzer
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany
| | - Bruno Stieger
- Department of Clinical Pharmacology and Toxicology, University Hospital, 8091 Zurich, Switzerland
| | - Regina Stöber
- Leibniz Research Centre for Working Environment and Human Factors (IFADO), 44139 Dortmund, Germany
| | - Yuichi Sugiyama
- Sugiyama Laboratory, RIKEN Innovation Center, RIKEN, Yokohama Biopharmaceutical R&D Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045 Japan
| | - Ciro Tetta
- Fresenius Medical Care, Bad Homburg, Germany
| | - Wolfgang E. Thasler
- Department of Surgery, Ludwig-Maximilians-University of Munich Hospital Grosshadern, Munich, Germany
| | - Tamara Vanhaecke
- Department of Toxicology, Centre for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 1090 Brussels, Belgium
| | - Mathieu Vinken
- Department of Toxicology, Centre for Pharmaceutical Research, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 1090 Brussels, Belgium
| | - Thomas S. Weiss
- Department of Pediatrics and Juvenile Medicine, University of Regensburg Hospital, Regensburg, Germany
| | - Agata Widera
- Leibniz Research Centre for Working Environment and Human Factors (IFADO), 44139 Dortmund, Germany
| | - Courtney G. Woods
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC USA
| | | | | | - Jan G. Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IFADO), 44139 Dortmund, Germany
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Harrill JA, Hukkanen RR, Lawson M, Martin G, Gilger B, Soldatow V, Lecluyse EL, Budinsky RA, Rowlands JC, Thomas RS. Knockout of the aryl hydrocarbon receptor results in distinct hepatic and renal phenotypes in rats and mice. Toxicol Appl Pharmacol 2013; 272:503-18. [PMID: 23859880 DOI: 10.1016/j.taap.2013.06.024] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 05/29/2013] [Accepted: 06/24/2013] [Indexed: 12/31/2022]
Abstract
The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor which plays a role in the development of multiple tissues and is activated by a large number of ligands, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In order to examine the roles of the AHR in both normal biological development and response to environmental chemicals, an AHR knockout (AHR-KO) rat model was created and compared with an existing AHR-KO mouse. AHR-KO rats harboring either 2-bp or 29-bp deletion mutation in exon 2 of the AHR were created on the Sprague-Dawley genetic background using zinc-finger nuclease (ZFN) technology. Rats harboring either mutation type lacked expression of AHR protein in the liver. AHR-KO rats were also insensitive to thymic involution, increased hepatic weight and the induction of AHR-responsive genes (Cyp1a1, Cyp1a2, Cyp1b1, Ahrr) following acute exposure to 25 μg/kg TCDD. AHR-KO rats had lower basal expression of transcripts for these genes and also accumulated ~30-45-fold less TCDD in the liver at 7 days post-exposure. In untreated animals, AHR-KO mice, but not AHR-KO rats, had alterations in serum analytes indicative of compromised hepatic function, patent ductus venosus of the liver and persistent hyaloid arteries in the eye. AHR-KO rats, but not AHR-KO mice, displayed pathological alterations to the urinary tract: bilateral renal dilation (hydronephrosis), secondary medullary tubular and uroepithelial degenerative changes and bilateral ureter dilation (hydroureter). The present data indicate that the AHR may play significantly different roles in tissue development and homeostasis and toxicity across rodent species.
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Key Words
- 2,3,7,8-tetracholorodibenzo-p-dioxin
- 90-kDa heat shock protein
- AHR
- AHR-KO
- AIP
- ALB
- ALP
- ALT
- ARNT
- AST
- Ahrr
- Aryl hydrocarbon receptor knockout mouse
- Aryl hydrocarbon receptor knockout rat
- BAS
- BILI
- BLO
- BUN
- CA
- CAOX
- CBC
- CHOL
- CL
- CREA
- CYP1A1
- CYP1A2
- CYP1B1
- Comparison
- DRE
- EOS
- EPI
- GGT
- GLOB
- GLUC
- HB
- HBSS
- HCT
- HSP90
- Hank's Balanced Salt Solution
- K
- KET
- Kidney
- LD(50)
- LEUC
- LYM
- Liver
- MCH
- MCHC
- MCV
- MON
- NA
- NEU
- PHOS
- PLT
- RBC
- SG
- TBA
- TBIL
- TCDD
- TP
- TPHO
- TRIG
- Tissue phenotypes
- UBIL
- UGLU
- ULEUC
- UPRO
- URBC
- UWBC
- WT
- ZFN
- alanine aminotransferase
- alkaline phosphatase
- aryl hydrocarbon receptor
- aryl hydrocarbon receptor interacting protein
- aryl hydrocarbon receptor knockout
- aryl hydrocarbon receptor nuclear translocator
- aryl hydrocarbon receptor repressor
- aspartate aminotransferase
- basophils
- blood urea nitrogen
- calcium
- calcium oxalate crystals
- chloride
- cholesterol
- complete blood count
- creatinine
- cytochrome P450, family 1, subfamily A, polypeptide 1
- cytochrome P450, family 1, subfamily A, polypeptide 2
- cytochrome P450, family 1, subfamily B, polypeptide 1
- dioxin-response element
- eosinophils
- hematocrit
- hemoglobin
- leukocytes
- lymphocytes
- mean corpuscular hemoglobin
- mean corpuscular hemoglobin concentration
- mean corpuscular volume
- median lethal dose
- monocytes
- neutrophils
- phosphorus
- platelets
- potassium
- red blood cells
- serum albumin
- serum globulin
- serum glucose
- sodium
- total bile acid
- total bilirubin
- total serum protein
- total white blood cells
- triglycerides
- triple phosphate crystals
- urine bilinogen
- urine bilirubin
- urine epithelial cells
- urine glucose
- urine ketones
- urine leukocytes
- urine occult blood
- urine protein
- urine red blood cells
- urine specific gravity
- wild-type
- zinc finger nuclease
- γ-glutamyl transpeptidase
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Affiliation(s)
- Joshua A Harrill
- The Hamner Institute for Health Sciences, Institute for Chemical Safety Sciences, RTP, NC 27709, USA
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De Boever P, Wens B, Boix J, Felipo V, Schoeters G. Perinatal Exposure to Purity-Controlled Polychlorinated Biphenyl 52, 138, or 180 Alters Toxicogenomic Profiles in Peripheral Blood of Rats after 4 Months. Chem Res Toxicol 2013; 26:1159-67. [DOI: 10.1021/tx300510v] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Patrick De Boever
- Unit Environmental Risk and
Health, Flemish Institute for Technological Research (VITO), Industriezone Vlasmeer 7, 2400 Mol, Belgium
- Centre for Environmental Sciences, Hasselt University, Agoralaan Building D, 3590 Diepenbeek,
Belgium
| | - Britt Wens
- Unit Environmental Risk and
Health, Flemish Institute for Technological Research (VITO), Industriezone Vlasmeer 7, 2400 Mol, Belgium
| | - Jordi Boix
- Laboratory of Neurobiology, Centro de Investigación Principe Felipe, Avenida
Autopista del Saler 16, 46012 Valencia, Spain
| | - Vicente Felipo
- Laboratory of Neurobiology, Centro de Investigación Principe Felipe, Avenida
Autopista del Saler 16, 46012 Valencia, Spain
| | - Greet Schoeters
- Unit Environmental Risk and
Health, Flemish Institute for Technological Research (VITO), Industriezone Vlasmeer 7, 2400 Mol, Belgium
- Department of Biomedical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp,
Belgium
- Department of Environmental
Medicine, University of Southern Denmark, J.B. Winslowsvej 17A, 5100 Odense, Denmark
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Rigaud C, Couillard CM, Pellerin J, Légaré B, Gonzalez P, Hodson PV. Relative potency of PCB126 to TCDD for sublethal embryotoxicity in the mummichog (Fundulus heteroclitus). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2013; 128-129:203-214. [PMID: 23314333 DOI: 10.1016/j.aquatox.2012.12.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 12/11/2012] [Accepted: 12/16/2012] [Indexed: 06/01/2023]
Abstract
The relative potency (ReP) of 3,3',4,4',5-pentachlorobiphenyl (PCB126) to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for sublethal responses was assessed in Fundulus heteroclitus embryos. Eggs were treated with intravitelline injections of graded sublethal doses of PCB126 (312-5000 pg g(-1) wet weight, ww) or TCDD (5-1280 pg g(-1) ww). At 16 days post-fertilization (DPF), craniofacial deformities were observed in larvae hatched from eggs treated with the two highest doses of PCB126 (2500-5000 pg g(-1) ww). Both compounds caused a dose-responsive reduction of larval growth and prey capture ability (at ≥1250 pg g(-1) ww), and induction of ethoxyresorufin-O-deethylase (EROD) activity (at ≥80 pg g(-1) ww). The dose-response relationships for EROD activity for PCB126 and TCDD had similar slopes and the ReP of PCB126 to TCDD for EROD activity was estimated at 0.71. This is 140-fold higher than the World Health Organization (WHO) TCDD equivalency factor (TEF) of PCB126 for fish (0.005), which is based on rainbow trout (Oncorhynchus mykiss) embryolethality data. The slope of the dose-response relationship for prey capture ability for PCB126 was steeper than for TCDD, suggesting different mechanisms of action. Expression levels of several genes were also studied by quantitative real-time polymerase chain reaction (qPCR) following exposure to single doses of TCDD or PCB126 (1280 and 1250 pg g(-1) ww, respectively) causing similar EROD induction. A different pattern of responses was observed between PCB126 and TCDD: PCB126 appeared to induce antioxidant responses by inducing sod2 expression, while TCDD did not. These results suggest that relative potencies are species-specific and that the current ReP for PCB126 underestimates its toxicity for some fish species. It is recommended to develop species-specific RePs for a variety of sublethal endpoints and at environmentally relevant doses.
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Affiliation(s)
- Cyril Rigaud
- Institut des Sciences de la Mer, Université du Québec à Rimouski, Rimouski, Québec, Canada
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34
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Forgacs AL, Dere E, Angrish MM, Zacharewski TR. Comparative analysis of temporal and dose-dependent TCDD-elicited gene expression in human, mouse, and rat primary hepatocytes. Toxicol Sci 2013; 133:54-66. [PMID: 23418086 DOI: 10.1093/toxsci/kft028] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)-elicited time- and dose-dependent differential gene expression was compared in human, mouse, and rat primary hepatocytes. Comprehensive time course (10 nM TCDD or dimethyl sulfoxide vehicle control for 1, 2, 4, 8, 12, 24, and 48h) studies identified 495, 2305, and 711 differentially expressed orthologous genes in human, mouse, and rat hepatocytes, respectively. However, only 16 orthologs were differentially expressed across all three species, with the majority of orthologs exhibiting species-specific expression (399 human, 2097 mouse, and 533 rat), consistent with species-specific expression reported in other in vitro and in vivo comparative studies. TCDD also elicited the dose-dependent induction of 397 human, 100 mouse, and 443 rat genes at 12h and 615 human, 426 mouse, and 314 rat genes at 24h. Comparable EC50 values were obtained for AhR battery genes including Cyp1a1 (0.1 nM human, 0.05 nM mouse, 0.08 nM rat at 24h) and Tiparp (0.97 nM human, 0.63 nM mouse, 0.14 nM rat at 12h). Overrepresented functions and pathways included amino acid metabolism in humans, immune response in mice, and energy homeostasis in rats. Differentially expressed genes functionally associated with lipid transport, processing, and metabolism were overrepresented in all three species but exhibited species-specific expression consistent with the induction of hepatic steatosis in mice but not in rats following a single oral gavage of TCDD. Furthermore, human primary hepatocytes showed lipid accumulation following 48h of treatment with TCDD, suggesting that AhR-mediated steatosis in mice more closely resembles human hepatic fat accumulation compared with that in rats. Collectively, these results suggest that species-specific gene expression profiles mediate the species-specific effects of TCDD despite the conservation of the AhR and its signaling mechanism.
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Affiliation(s)
- Agnes L Forgacs
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan 48824, USA
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35
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Abstract
Biomarkers are characteristics objectively measured and evaluated as indicators of: normal biologic processes, pathogenic processes, or pharmacologic response(s) to a therapeutic intervention. In environmental research and risk assessment, biomarkers are frequently referred to as indicators of human or environmental hazards. Discovering and implementing new biomarkers for toxicity caused by exposure to a chemical either from a therapeutic intervention or accidentally through the environment continues to be pursued through the use of animal models to predict potential human effects, from human studies (clinical or epidemiologic) or biobanked human samples, or the combination of all such approaches. The key to discovering or inferring biomarkers through computational means involves the identification or prediction of the molecular target(s) of the chemical(s) and the association of these targets with perturbed biological pathways. Two examples are given in this chapter: (1) inferring potential human biomarkers from animal toxicogenomics data, and (2) the identification of protein targets through computational means and associating these in one example with potential drug interactions and in another case with increasing the risk of developing certain human diseases.
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36
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Nault R, Kim S, Zacharewski TR. Comparison of TCDD-elicited genome-wide hepatic gene expression in Sprague-Dawley rats and C57BL/6 mice. Toxicol Appl Pharmacol 2012; 267:184-91. [PMID: 23238561 DOI: 10.1016/j.taap.2012.11.028] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 11/16/2012] [Accepted: 11/19/2012] [Indexed: 12/16/2022]
Abstract
Although the structure and function of the AhR are conserved, emerging evidence suggests that downstream effects are species-specific. In this study, rat hepatic gene expression data from the DrugMatrix database (National Toxicology Program) were compared to mouse hepatic whole-genome gene expression data following treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). For the DrugMatrix study, male Sprague-Dawley rats were gavaged daily with 20μg/kg TCDD for 1, 3 and 5days, while female C57BL/6 ovariectomized mice were examined 1, 3 and 7days after a single oral gavage of 30μg/kg TCDD. A total of 649 rat and 1386 mouse genes (|fold change|≥1.5, P1(t)≥0.99) were differentially expressed following treatment. HomoloGene identified 11,708 orthologs represented across the rat Affymetrix 230 2.0 GeneChip (12,310 total orthologs), and the mouse 4×44K v.1 Agilent oligonucleotide array (17,578 total orthologs). Comparative analysis found 563 and 922 orthologs differentially expressed in response to TCDD in the rat and mouse, respectively, with 70 responses associated with immune function and lipid metabolism in common to both. Moreover, QRTPCR analysis of Ceacam1, showed divergent expression (induced in rat; repressed in mouse) functionally consistent with TCDD-elicited hepatic steatosis in the mouse but not the rat. Functional analysis identified orthologs involved in nucleotide binding and acetyltransferase activity in rat, while mouse-specific responses were associated with steroid, phospholipid, fatty acid, and carbohydrate metabolism. These results provide further evidence that TCDD elicits species-specific regulation of distinct gene networks, and outlines considerations for future comparisons of publicly available microarray datasets.
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Affiliation(s)
- Rance Nault
- Department of Biochemistry and Molecular Biology, Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824, USA
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37
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Tuomisto J, Tuomisto JT. Is the fear of dioxin cancer more harmful than dioxin? Toxicol Lett 2012; 210:338-44. [PMID: 22387160 DOI: 10.1016/j.toxlet.2012.02.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 02/06/2012] [Accepted: 02/07/2012] [Indexed: 01/08/2023]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a proven animal carcinogen. Occupational cohorts with the highest exposures imply that there is a small risk of all cancers combined, but it is difficult to pinpoint the confounding effect of the main chemicals. Studies after major accidents do not unequivocally confirm this risk. The risks to populations at the current dioxin levels seem trivial if present at all. There is increasing evidence that the aryl hydrocarbon receptor (AhR), i.e. the so called "dioxin receptor", is a physiological transcription factor exerting important functions in the body. Consequently a certain level of AhR activation may be beneficial rather than harmful. This challenges the wisdom of excessive regulation of dioxin levels in certain foods and nutrients. This could pose indirect nutritional risks, in fact being more harmful than even the worst case predictions of the putative cancer risks attributable to dioxins.
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Affiliation(s)
- Jouko Tuomisto
- Department of Environmental Health, National Institute for Health and Welfare (THL), P.O. Box 95, FI-70701 Kuopio, Finland.
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38
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Black MB, Budinsky RA, Dombkowski A, Cukovic D, LeCluyse EL, Ferguson SS, Thomas RS, Rowlands JC. Cross-species comparisons of transcriptomic alterations in human and rat primary hepatocytes exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin. Toxicol Sci 2012; 127:199-215. [PMID: 22298810 DOI: 10.1093/toxsci/kfs069] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A toxicogenomics approach was used to qualitatively and quantitatively compare the gene expression changes in human and rat primary hepatocytes exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Hepatocytes from five individual rats and five individual humans were exposed for 24 h to 11 concentrations of TCDD ranging from 0.00001 to 100nM and a vehicle control. Gene expression changes were analyzed using whole-genome microarrays containing 13,002 orthologs. Significant changes in expression of individual orthologs at any concentration (fold change [FC] ± 1.5 and false discovery rate < 0.05) were higher in the rat (1547) compared with human hepatocytes (475). Only 158 differentially expressed orthologs were common between rats and humans. Enrichment analysis was performed on the differentially expressed orthologs in each species with 49 and 34 enriched human and rat pathways, respectively. Only 12 enriched pathways were shared between the two species. The results demonstrate significant cross-species differences in expression at both the gene and pathway level. Benchmark dose analysis of gene expression changes showed an average 18-fold cross-species difference in potency among differentially expressed orthologs with the rat more sensitive than the human. Similar cross-species differences in potency were observed for signaling pathways. Using the maximum FC in gene expression as a measure of efficacy, the human hepatocytes showed on average a 20% lower efficacy among the individual orthologs showing differential expression. The results provide evidence for divergent cross-species gene expression changes in response to TCDD and are consistent with epidemiological and clinical evidence showing humans to be less sensitive to TCDD-induced hepatotoxicity.
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Affiliation(s)
- Michael B Black
- The Hamner Institutes for Health Sciences, Research Triangle Park, North Carolina 27709, USA
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39
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Michaelson JJ, Trump S, Rudzok S, Gräbsch C, Madureira DJ, Dautel F, Mai J, Attinger S, Schirmer K, von Bergen M, Lehmann I, Beyer A. Transcriptional signatures of regulatory and toxic responses to benzo-[a]-pyrene exposure. BMC Genomics 2011; 12:502. [PMID: 21995607 PMCID: PMC3215681 DOI: 10.1186/1471-2164-12-502] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 10/13/2011] [Indexed: 01/01/2023] Open
Abstract
Background Small molecule ligands often have multiple effects on the transcriptional program of a cell: they trigger a receptor specific response and additional, indirect responses ("side effects"). Distinguishing those responses is important for understanding side effects of drugs and for elucidating molecular mechanisms of toxic chemicals. Results We explored this problem by exposing cells to the environmental contaminant benzo-[a]-pyrene (B[a]P). B[a]P exposure activates the aryl hydrocarbon receptor (Ahr) and causes toxic stress resulting in transcriptional changes that are not regulated through Ahr. We sought to distinguish these two types of responses based on a time course of expression changes measured after B[a]P exposure. Using Random Forest machine learning we classified 81 primary Ahr responders and 1,308 genes regulated as side effects. Subsequent weighted clustering gave further insight into the connection between expression pattern, mode of regulation, and biological function. Finally, the accuracy of the predictions was supported through extensive experimental validation. Conclusion Using a combination of machine learning followed by extensive experimental validation, we have further expanded the known catalog of genes regulated by the environmentally sensitive transcription factor Ahr. More broadly, this study presents a strategy for distinguishing receptor-dependent responses and side effects based on expression time courses.
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Affiliation(s)
- Jacob J Michaelson
- Cellular Networks and Systems Biology, Biotechnology Center, TU Dresden, Dresden, Germany
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Abstract
Activation of the KEAP1-NRF2 signaling pathway is an adaptive response to environmental and endogenous stresses and serves to render animals resistant to chemical carcinogenesis and other forms of toxicity, whereas disruption of the pathway exacerbates these outcomes. This pathway, which can be activated by sulfhydryl-reactive, small-molecule pharmacologic agents, regulates the inducible expression of an extended battery of cytoprotective genes, often by direct binding of the transcription factor to antioxidant response elements in the promoter regions of target genes. However, it is becoming evident that some of the protective effects may be mediated indirectly through cross talk with additional pathways affecting cell survival and other aspects of cell fate. These interactions provide a multi-tiered, integrated response to chemical stresses. This review highlights recent observations on the molecular interactions and their functional consequences between NRF2 and the arylhydrocarbon receptor (AhR), NF-κB, p53, and Notch1 signaling pathways.
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Affiliation(s)
- Nobunao Wakabayashi
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pennsylvania 15261, USA
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Dioxins, the aryl hydrocarbon receptor and the central regulation of energy balance. Front Neuroendocrinol 2010; 31:452-78. [PMID: 20624415 DOI: 10.1016/j.yfrne.2010.07.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 06/15/2010] [Accepted: 07/05/2010] [Indexed: 01/03/2023]
Abstract
Dioxins are ubiquitous environmental contaminants that have attracted toxicological interest not only for the potential risk they pose to human health but also because of their unique mechanism of action. This mechanism involves a specific, phylogenetically old intracellular receptor (the aryl hydrocarbon receptor, AHR) which has recently proven to have an integral regulatory role in a number of physiological processes, but whose endogenous ligand is still elusive. A major acute impact of dioxins in laboratory animals is the wasting syndrome, which represents a puzzling and dramatic perturbation of the regulatory systems for energy balance. A single dose of the most potent dioxin, TCDD, can permanently readjust the defended body weight set-point level thus providing a potentially useful tool and model for physiological research. Recent evidence of response-selective modulation of AHR action by alternative ligands suggests further that even therapeutic implications might be possible in the future.
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Sutter CH, Bodreddigari S, Sutter TR, Carlson EA, Silkworth JB. Analysis of the CYP1A1 mRNA dose-response in human keratinocytes indicates that relative potencies of dioxins, furans, and PCBs are species and congener specific. Toxicol Sci 2010; 118:704-15. [PMID: 20819910 DOI: 10.1093/toxsci/kfq262] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Reports indicate that toxic equivalency factors (TEFs) based primarily on rodent data do not accurately predict in vitro human responsiveness to certain dioxin-like chemicals (DLCs). To investigate this in cells responsive to dioxins and relevant to chloracne, normal human epidermal keratinocytes were treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and several DLCs, each with a TEF value of 0.1, representing three classes of congeners. We estimated half maximal effective concentration (EC50)-based donor-specific relative potency (REP) values for cytochrome P450 1A1 (CYP1A1) messenger RNA (mRNA) induction for TCDD, 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin (HxCDD), 2,3,7,8-tetrachlorodibenzofuran (TCDF), 1,2,3,6,7,8-hexachlorodibenzofuran (HxCDF), and 3,3',4,4',5-pentachlorobiphenyl (PCB 126). We also determined EC50-based population-level REP values (n = 4) for CYP1A1 mRNA induction for TCDD, HxCDF, and PCB 126. Furthermore, an alternative factor, the relative threshold factor (RTF) based on the low end (threshold) of the dose-response curve, was calculated. Our results demonstrated that HxCDF had a population-based REP value of 0.98, 9.8-fold higher than its assigned TEF value of 0.1. Conversely, PCB 126 had an REP value of 0.0027 and an RTF of 0.0022, 37-fold and 45-fold less than its assigned TEF of 0.1, respectively. The REP values for HxCDD and TCDF were 0.24 and 0.10, respectively, similar to their assigned value of 0.1. Therefore, although the DLCs tested in the current study all possessed the same assigned TEF value of 0.1, congener-specific differences in REPs and RTFs were observed for human keratinocytes. These congener-specific discrepancies are likely because of differences in interspecies factors that have yet to be defined.
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Affiliation(s)
- Carrie H Sutter
- Department of Biological Sciences and W. Harry Feinstone Center for Genomic Research, University of Memphis, Memphis, Tennessee 38152-3560, USA.
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Le Vee M, Jouan E, Fardel O. Involvement of aryl hydrocarbon receptor in basal and 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced expression of target genes in primary human hepatocytes. Toxicol In Vitro 2010; 24:1775-81. [DOI: 10.1016/j.tiv.2010.07.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Revised: 06/16/2010] [Accepted: 07/01/2010] [Indexed: 11/29/2022]
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Tan KP, Wang B, Yang M, Boutros PC, MacAulay J, Xu H, Chuang AI, Kosuge K, Yamamoto M, Takahashi S, Wu AML, Ross DD, Harper PA, Ito S. Aryl Hydrocarbon Receptor Is a Transcriptional Activator of the Human Breast Cancer Resistance Protein (BCRP/ABCG2). Mol Pharmacol 2010; 78:175-85. [DOI: 10.1124/mol.110.065078] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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Flaveny CA, Murray IA, Perdew GH. Differential gene regulation by the human and mouse aryl hydrocarbon receptor. Toxicol Sci 2009. [PMID: 20044593 DOI: 10.1093/toxsci/kfp30] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The human aryl hydrocarbon receptor (hAHR) and mouse aryl hydrocarbon receptor (mAHR(b)) share limited (58%) transactivation domain (TAD) sequence identity. Compared to the mAHR(b) allele, the hAHR displays 10-fold lower relative affinity for prototypical ligands, such as 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD). However, in previous studies, we have demonstrated that the hAHR can display a higher relative ligand-binding affinity than the mAHR(b) for specific AHR ligands, such as indirubin. Each receptor has also been shown to differentially recruit LXXLL coactivator motif proteins and to utilize different TAD subdomains in gene transactivation. Using hepatocytes isolated from C57BL/6J mice (Ahr(b/b)) and AHR(Ttr) transgenic mice, which express hAHR protein specifically in hepatocytes, we investigated whether the hAHR and mAHR(b) differentially regulate genes. DNA microarray and quantitative PCR analysis of Ahr(b/b) and AHR(Ttr) primary mouse hepatocytes treated with 10nM TCDD revealed that a number of established AHR target genes such as Cyp1a1 and Cyp1b1 are significantly induced by both receptors. Remarkably, of the 1752 genes induced by mAHR(b) and 1186 genes induced by hAHR, only 265 genes (approximately 18%) were significantly activated by both receptors in response to TCDD. Conversely, of the 1100 and 779 genes significantly repressed in mAHR(b) and hAHR hepatocytes, respectively, only 462 (approximately 49%) genes were significantly repressed by both receptors in response to TCDD treatment. Genes identified as differentially expressed are known to be involved in a number of biological pathways, including cell proliferation and inflammatory response, which suggest that compared to the mAHR(b), the hAHR may play contrasting roles in TCDD-induced toxicity and endogenous AHR-mediated gene regulation.
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Affiliation(s)
- Colin A Flaveny
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Flaveny CA, Murray IA, Perdew GH. Differential gene regulation by the human and mouse aryl hydrocarbon receptor. Toxicol Sci 2009; 114:217-25. [PMID: 20044593 DOI: 10.1093/toxsci/kfp308] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The human aryl hydrocarbon receptor (hAHR) and mouse aryl hydrocarbon receptor (mAHR(b)) share limited (58%) transactivation domain (TAD) sequence identity. Compared to the mAHR(b) allele, the hAHR displays 10-fold lower relative affinity for prototypical ligands, such as 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD). However, in previous studies, we have demonstrated that the hAHR can display a higher relative ligand-binding affinity than the mAHR(b) for specific AHR ligands, such as indirubin. Each receptor has also been shown to differentially recruit LXXLL coactivator motif proteins and to utilize different TAD subdomains in gene transactivation. Using hepatocytes isolated from C57BL/6J mice (Ahr(b/b)) and AHR(Ttr) transgenic mice, which express hAHR protein specifically in hepatocytes, we investigated whether the hAHR and mAHR(b) differentially regulate genes. DNA microarray and quantitative PCR analysis of Ahr(b/b) and AHR(Ttr) primary mouse hepatocytes treated with 10nM TCDD revealed that a number of established AHR target genes such as Cyp1a1 and Cyp1b1 are significantly induced by both receptors. Remarkably, of the 1752 genes induced by mAHR(b) and 1186 genes induced by hAHR, only 265 genes (approximately 18%) were significantly activated by both receptors in response to TCDD. Conversely, of the 1100 and 779 genes significantly repressed in mAHR(b) and hAHR hepatocytes, respectively, only 462 (approximately 49%) genes were significantly repressed by both receptors in response to TCDD treatment. Genes identified as differentially expressed are known to be involved in a number of biological pathways, including cell proliferation and inflammatory response, which suggest that compared to the mAHR(b), the hAHR may play contrasting roles in TCDD-induced toxicity and endogenous AHR-mediated gene regulation.
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Affiliation(s)
- Colin A Flaveny
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Hervé JC, Crump D, Jones SP, Mundy LJ, Giesy JP, Zwiernik MJ, Bursian SJ, Jones PD, Wiseman SB, Wan Y, Kennedy SW. Cytochrome P4501A Induction by 2,3,7,8-Tetrachlorodibenzo-p-Dioxin and Two Chlorinated Dibenzofurans in Primary Hepatocyte Cultures of Three Avian Species. Toxicol Sci 2009; 113:380-91. [DOI: 10.1093/toxsci/kfp270] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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