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Veland N, Gleneadie HJ, Brown KE, Sardini A, Pombo J, Dimond A, Burns V, Sarkisyan K, Schiering C, Webster Z, Merkenschlager M, Fisher AG. Bioluminescence imaging of Cyp1a1-luciferase reporter mice demonstrates prolonged activation of the aryl hydrocarbon receptor in the lung. Commun Biol 2024; 7:442. [PMID: 38600349 PMCID: PMC11006662 DOI: 10.1038/s42003-024-06089-6] [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: 05/30/2023] [Accepted: 03/21/2024] [Indexed: 04/12/2024] Open
Abstract
Aryl hydrocarbon receptor (AHR) signalling integrates biological processes that sense and respond to environmental, dietary, and metabolic challenges to ensure tissue homeostasis. AHR is a transcription factor that is inactive in the cytosol but upon encounter with ligand translocates to the nucleus and drives the expression of AHR targets, including genes of the cytochrome P4501 family of enzymes such as Cyp1a1. To dynamically visualise AHR activity in vivo, we generated reporter mice in which firefly luciferase (Fluc) was non-disruptively targeted into the endogenous Cyp1a1 locus. Exposure of these animals to FICZ, 3-MC or to dietary I3C induced strong bioluminescence signal and Cyp1a1 expression in many organs including liver, lung and intestine. Longitudinal studies revealed that AHR activity was surprisingly long-lived in the lung, with sustained Cyp1a1 expression evident in discrete populations of cells including columnar epithelia around bronchioles. Our data link diet to lung physiology and also reveal the power of bespoke Cyp1a1-Fluc reporters to longitudinally monitor AHR activity in vivo.
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Affiliation(s)
- Nicolas Veland
- Epigenetic Memory Group, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 OHS, UK
| | - Hannah J Gleneadie
- Epigenetic Memory Group, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 OHS, UK
| | - Karen E Brown
- Epigenetic Memory Group, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 OHS, UK
| | - Alessandro Sardini
- Whole Animal Physiology and Imaging, MRC Laboratory of Medical Sciences, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, UK
| | - Joaquim Pombo
- Senescence Group, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, UK
| | - Andrew Dimond
- Epigenetic Memory Group, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 OHS, UK
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
| | - Vanessa Burns
- Epigenetic Memory Group, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 OHS, UK
| | - Karen Sarkisyan
- Synthetic Biology Group, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, UK
| | - Chris Schiering
- Inflammation and Obesity Group, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, UK
| | - Zoe Webster
- Transgenics & Embryonic Stem Cell Facility, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, UK
| | - Matthias Merkenschlager
- Lymphocyte Development Group, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, UK
| | - Amanda G Fisher
- Epigenetic Memory Group, MRC Laboratory of Medical Sciences, Imperial College London Hammersmith Hospital Campus, Du Cane Road, London, W12 OHS, UK.
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK.
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2
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El-Mahrouk SR, El-Ghiaty MA, Alqahtani MA, El-Kadi AOS. Dimethylmonothioarsinic acid (DMMTA V) differentially modulates the expression of AHR-regulated cytochrome P450 1A enzymes in vivo and in vitro. Toxicol Lett 2024; 394:32-45. [PMID: 38403205 DOI: 10.1016/j.toxlet.2024.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 02/07/2024] [Accepted: 02/21/2024] [Indexed: 02/27/2024]
Abstract
Dimethylmonothioarsinic acid (DMMTAV), a pentavalent thio-arsenic derivative, has been found in bodily fluids and tissues including urine, liver, kidney homogenates, plasma, and red blood cells. Although DMMTAV is a minor metabolite in humans and animals, its substantial toxicity raises concerns about potential carcinogenic effects. This toxicity could be attributed to arsenicals' ability to regulate cytochrome P450 1 A (CYP1A) enzymes, pivotal in procarcinogen activation or detoxification. The current study investigates DMMTAV's impact on CYP1A1/2 expression, individually and in conjunction with its inducer, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). C57BL/6 mice were intraperitoneally injected with 6 mg/kg DMMTAV, alone or with 15 μg/kg TCDD, for 6 and 24 h. Similarly, Hepa-1c1c7 cells were exposed to DMMTAV (0.5, 1, and 2 μM) with or without 1 nM TCDD for 6 and 24 h. DMMTAV hindered TCDD-induced elevation of Cyp1a1 mRNA, both in vivo (at 6 h) and in vitro, associated with reduced CYP1A regulatory element activation. Interestingly, in C57BL/6 mice, DMMTAV boosted TCDD-induced CYP1A1/2 protein and activity, unlike Hepa-1c1c7 cells where it suppressed both. DMMTAV co-exposure increased TCDD-induced Cyp1a2 mRNA. While Cyp1a1 mRNA stability remained unchanged, DMMTAV negatively affected protein stability, indicated by shortened half-life. Baseline levels of CYP1A1/2 mRNA, protein, and catalytic activities showed no significant alterations in DMMTAV-treated C57BL/6 mice and Hepa-1c1c7 cells. Taken together, these findings indicate, for the first time, that DMMTAV differentially modulates the TCDD-mediated induction of AHR-regulated enzymes in both liver of C57BL/6 mice and murine Hepa-1c1c7 cells suggesting that thio-arsenic pentavalent metabolites are extremely reactive and could play a role in the toxicity of arsenic.
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Affiliation(s)
- Sara R El-Mahrouk
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada; Faculty of Pharmacy, Tanta University, Tanta, Gharbia, Egypt
| | - Mahmoud A El-Ghiaty
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Mohammed A Alqahtani
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Ayman O S El-Kadi
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada.
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3
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Alqahtani MA, El-Ghiaty MA, El-Mahrouk SR, El-Kadi AOS. Differential Modulatory Effects of Methylmercury (MeHg) on Ahr-regulated Genes in Extrahepatic Tissues of C57BL/6 Mice. Biol Trace Elem Res 2024:10.1007/s12011-023-04050-y. [PMID: 38197905 DOI: 10.1007/s12011-023-04050-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 12/27/2023] [Indexed: 01/11/2024]
Abstract
Methylmercury (MeHg) and 2,3,7,8-tetrachlorodibenzodioxin (TCDD) are potent environmental pollutants implicated in the modulation of xenobiotic-metabolizing enzymes, particularly the cytochrome P450 1 family (CYP1) which is regulated by the aryl hydrocarbon receptor (AHR). However, the co-exposure to MeHg and TCDD raises concerns about their potential combined effects, necessitating thorough investigation. The primary objective of this study was to investigate the individual and combined effects of MeHg and TCDD on AHR-regulated CYP1 enzymes in mouse extrahepatic tissues. Therefore, C57BL/6 mice were administrated with MeHg (2.5 mg/kg) in the absence and presence of TCDD (15 μg/kg) for 6 and 24 h. The AHR-regulated CYP1 mRNA and protein expression levels were measured in the heart, lung, and kidney, using RT real-time PCR and western blot, respectively. Interestingly, treatment with MeHg exhibited mainly inhibitory effect, particularly, it decreased the basal level of Cyp1a1 and Cyp1a2 mRNA and protein, and that was more evident at the 24 h time point in kidney followed by heart. Similarly, when mice were co-exposed, MeHg was able to reduce the TCDD-induced Cyp1a1 and Cyp1a2 expression, however, MeHg potentiated kidney Cyp1b1 mRNA expression, opposing the observed change on its protein level. Also, MeHg induced antioxidant NAD(P)H:quinone oxidoreductase (NQO1) mRNA and protein in kidney, while heme-oxygenase (HO-1) mRNA was up-regulated in heart and kidney. In conclusion, this study reveals intricate interplay between MeHg and TCDD on AHR-regulated CYP1 enzymes, with interesting inhibitory effects observed that might be significant for procarcinogen metabolism. Varied responses across tissues highlight the potential implications for environmental health.
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Affiliation(s)
- Mohammed A Alqahtani
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, 2142J Katz Group-Rexall Centre for Pharmacy and Health Research, Edmonton, Alberta, T6G 2E1, Canada
| | - Mahmoud A El-Ghiaty
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, 2142J Katz Group-Rexall Centre for Pharmacy and Health Research, Edmonton, Alberta, T6G 2E1, Canada
| | - Sara R El-Mahrouk
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, 2142J Katz Group-Rexall Centre for Pharmacy and Health Research, Edmonton, Alberta, T6G 2E1, Canada
| | - Ayman O S El-Kadi
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, 2142J Katz Group-Rexall Centre for Pharmacy and Health Research, Edmonton, Alberta, T6G 2E1, Canada.
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4
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Kukal S, Thakran S, Kanojia N, Yadav S, Mishra MK, Guin D, Singh P, Kukreti R. Genic-intergenic polymorphisms of CYP1A genes and their clinical impact. Gene 2023; 857:147171. [PMID: 36623673 DOI: 10.1016/j.gene.2023.147171] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/16/2022] [Accepted: 01/03/2023] [Indexed: 01/08/2023]
Abstract
The humancytochrome P450 1A (CYP1A) subfamily genes, CYP1A1 and CYP1A2, encoding monooxygenases are critically involved in biotransformation of key endogenous substrates (estradiol, arachidonic acid, cholesterol) and exogenous compounds (smoke constituents, carcinogens, caffeine, therapeutic drugs). This suggests their significant involvement in multiple biological pathways with a primary role of maintaining endogenous homeostasis and xenobiotic detoxification. Large interindividual variability exist in CYP1A gene expression and/or catalytic activity of the enzyme, which is primarily due to the existence of polymorphic alleles which encode them. These polymorphisms (mainly single nucleotide polymorphisms, SNPs) have been extensively studied as susceptibility factors in a spectrum of clinical phenotypes. An in-depth understanding of the effects of polymorphic CYP1A genes on the differential metabolic activity and the resulting biological pathways is needed to explain the clinical implications of CYP1A polymorphisms. The present review is intended to provide an integrated understanding of CYP1A metabolic activity with unique substrate specificity and their involvement in physiological and pathophysiological roles. The article further emphasizes on the impact of widely studied CYP1A1 and CYP1A2 SNPs and their complex interaction with non-genetic factors like smoking and caffeine intake on multiple clinical phenotypes. Finally, we attempted to discuss the alterations in metabolism/physiology concerning the polymorphic CYP1A genes, which may underlie the reported clinical associations. This knowledge may provide insights into the disease pathogenesis, risk stratification, response to therapy and potential drug targets for individuals with certain CYP1A genotypes.
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Affiliation(s)
- Samiksha Kukal
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Sarita Thakran
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Neha Kanojia
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Saroj Yadav
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Manish Kumar Mishra
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Department of Biotechnology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042, India
| | - Debleena Guin
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Department of Biotechnology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042, India
| | - Pooja Singh
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Ritushree Kukreti
- Genomics and Molecular Medicine Unit, Institute of Genomics and Integrative Biology (IGIB), Council of Scientific and Industrial Research (CSIR), Delhi 110007, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
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5
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Modulation of cytochrome P450 1A (CYP1A) enzymes by monomethylmonothioarsonic acid (MMMTA V) in vivo and in vitro. Chem Biol Interact 2023; 376:110447. [PMID: 36893905 DOI: 10.1016/j.cbi.2023.110447] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 02/20/2023] [Accepted: 03/06/2023] [Indexed: 03/09/2023]
Abstract
Inorganic arsenic (iAs) is a natural toxicant which, upon entering the biosphere, undergoes extensive biotransformation and becomes a portal for generating various organic intermediates/products. The chemical diversity of iAs-derived organoarsenicals (oAs) is accompanied by varying degree of toxicity that can be held responsible, at least partly, for the overall health outcome of the originally encountered parent inorganic molecule. Such toxicity may originate from arsenicals ability to modulate cytochrome P450 1A (CYP1A) enzymes, whose activity is critical in activating/detoxifying procarcinogens. In this study, we evaluated the effect of monomethylmonothioarsonic acid (MMMTAV) on CYP1A1 and CYP1A2 in absence and presence of their inducer; 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Therefore, C57BL/6 mice were intraperitoneally injected with 12.5 mg/kg MMMTAV, with or without 15 μg/kg TCDD for 6 and 24 h. Moreover, murine Hepa-1c1c7 and human HepG2 cells were treated with MMMTAV (1, 5, and 10 μM), with or without 1 nM TCDD for 6 and 24 h. MMMTAV significantly inhibited TCDD-mediated induction of CYP1A1 mRNA, both in vivo and in vitro. This effect was attributed to decreased transcriptional activation of CYP1A regulatory element. Interestingly, MMMTAV significantly increased TCDD-induced CYP1A1 protein and activity in C57BL/6 mice and Hepa-1c1c7 cells, while both were significantly inhibited by MMMTAV treatment in HepG2 cells. CYP1A2 mRNA, protein and activity induced by TCDD were significantly increased by MMMTAV co-exposure. MMMTAV had no effect on CYP1A1 mRNA stability or protein stability and did not alter their half-lives. At basal level, only CYP1A1 mRNA was significantly decreased in MMMTAV-treated Hepa-1c1c7 cells. Our findings show that MMMTAV exposure potentiates procarcinogen-induced catalytic activity of both CYP1A1 and CYP1A2 in vivo. This effect entails excessive activation of such procarcinogens upon co-exposure, with potentially negative health-related outcomes.
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6
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Wallace SJ, de Solla SR, Langlois VS. Phenology of the transcriptome coincides with the physiology of double-crested cormorant embryonic development. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART D, GENOMICS & PROTEOMICS 2022; 44:101029. [PMID: 36302318 DOI: 10.1016/j.cbd.2022.101029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/19/2022] [Accepted: 10/05/2022] [Indexed: 11/09/2022]
Abstract
The rigorous timing of the dynamic transcriptome within the embryo has to be well orchestrated for normal development. Identifying the phenology of the transcriptome along with the physiology of embryonic development in birds may suggest periods of increased sensitivity to contaminant exposure depending on the contaminant's mechanism of action. Double-crested cormorants (Nannopterum auritum, formerly Phalacrocorax auritus) are commonly used in ecotoxicological studies, but relatively little is known about their functional transcriptome profile in early development. In this study, we tracked the phenology of the transcriptome during N. auritum embryogenesis. Fresh eggs were collected from a reference site and artificially incubated from collection until four days prior to hatching. Embryos were periodically sampled throughout incubation for a total of seven time points. A custom microarray was designed for cormorants (over 14,000 probes) and used for transcriptome analysis in whole body (days 5, 8) and liver tissue (days 12, 14, 16, 20, 24). Three main developmental periods (early, mid, and late incubation) were identified with differentially expressed genes, gene sets, and pathways within and between each developmental transition. Overall, the timing of differentially expressed genes and enriched pathways corresponded to previously documented changes in morphology, neurology, or physiology during avian embryonic development. Targeted investigation of a subset of genes involved in endogenous and xenobiotic metabolism (e.g., cytochrome P450 cyp1a, cyp1b1, superoxide dismutase 1 sod1) were expressed in a pattern similar to reported endogenous compound levels. These data can provide insights on normal embryonic development in an ecologically relevant species without any environmental contaminant exposure.
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Affiliation(s)
- Sarah J Wallace
- Institut national de la recherche scientifique (INRS), Centre Eau Terre Environnement, Quebec, QC, Canada. https://twitter.com/@sjwallace06
| | - Shane R de Solla
- Ecotoxicology and Wildlife Health Division, Environment and Climate Change Canada, Burlington, ON, Canada
| | - Valerie S Langlois
- Institut national de la recherche scientifique (INRS), Centre Eau Terre Environnement, Quebec, QC, Canada.
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7
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El-Ghiaty MA, Alqahtani MA, El-Kadi AOS. Down-regulation of hepatic cytochromes P450 1A1 and 1A2 by arsenic trioxide (ATO) in vivo and in vitro: A role of heme oxygenase 1. Chem Biol Interact 2022; 364:110049. [PMID: 35872050 DOI: 10.1016/j.cbi.2022.110049] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 07/03/2022] [Accepted: 07/13/2022] [Indexed: 11/03/2022]
Abstract
Arsenic trioxide (ATO) has evolved from an environmental threat to a successful therapy for acute promyelocytic leukemia (APL) and probably for solid tumors in the future. However, its efficacy comes at a cost of multi-organ toxicity whose mechanism remains unresolved. Arsenicals have been reported to modulate cytochrome P450 1A (CYP1A) enzymes, thus modifying activation/detoxification of drugs/procarcinogens. Therefore, this study aimed to investigate the possible effects of ATO on CYP1A1 and CYP1A2, in absence and presence of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) using in vivo and in vitro models. For this purpose, C57BL/6 mice were intraperitoneally injected with 8 mg/kg ATO with or without 15 μg/kg TCDD for 6 and 24 h. Furthermore, HepG2 cells were treated with ATO (1, 5, and 10 μM) with or without 1 nM TCDD for 6 and 24 h. ATO significantly inhibited TCDD-mediated induction of CYP1A1/1A2 mRNA, protein, and activity in both models. ATO differentially modulated CYP1A1/1A2 basal levels in vivo. We also demonstrated that ATO downregulates CYP1A through inhibiting the transcriptional activation of its regulatory element at both basal and inducible levels. Additionally, ATO significantly induced mRNA and protein of heme oxygenase 1 (HMOX1) in vivo and in vitro. In HepG2 cells, inhibition of HMOX1 by tin (IV) mesoporphyrin (IX) (SnMP) resulted in a partial restoration of the TCDD-mediated induction of CYP1A1 activity that was inhibited by ATO co-exposure. Our findings show that ATO alters both constitutive and inducible CYP1A1/1A2 expressions through transcriptional and HMOX1-mediated post-translational mechanisms. This implies the possible involvement of ATO in clearance-related consequences for the substrates of these enzymes such as drug-drug interactions or suboptimal toxicant elimination.
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Affiliation(s)
- Mahmoud A El-Ghiaty
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Mohammed A Alqahtani
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Ayman O S El-Kadi
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada.
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8
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Jiang J, Zhu J, Liu Q, Zhang T, Wen J, Xia J, Deng Y. Role of DNA methylation-related chromatin remodeling in aryl hydrocarbon receptor-dependent regulation of T-2 toxin highly inducible Cytochrome P450 1A4 gene. FASEB J 2021; 35:e21469. [PMID: 33788981 DOI: 10.1096/fj.202002570rr] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/05/2021] [Accepted: 02/08/2021] [Indexed: 11/11/2022]
Abstract
Mycotoxins are toxic secondary metabolites produced by food-contaminating fungi, which lead to global epigenetic changes and cause toxicity to both farm animals and humans. However, whether mycotoxins induce gene-specific epigenetic alterations associated with inducible downstream gene expression is unclear as are the underlying regulatory mechanisms. Here, we found that T-2 toxin and its deacetylated metabolites but not deoxynivalenol (DON) or other representative mycotoxins highly induced the expression of cytochrome P450 1A4 (CYP1A4) in both Leghorn male hepatoma (LMH) cells and chicken primary hepatocytes, and this effect was related to the regulation of both aryl hydrocarbon receptor (AhR) and DNA methylation. We used methylation-sensitive restriction enzyme digestion-qPCR (MSRE-qPCR) and chromatin immunoprecipitation (ChIP) assays and found that the binding of DNA methyltransferase 1 (DNMT1) and histone deacetylase 2 (HDAC2) to highly methylated CpG island 3-2 at the enhancer of CYP1A4 was accompanied by the recruitment of the repressive histone modification marker H3K27me3, inducing a silent state. In turn, T-2 toxin stimulation enriched the binding of AhR to demethylated CpG island 3-2, which facilitated p300 and H3K9ac recruitment and ultimately generated an activated chromatin structure at the enhancer by increasing the active histone modification markers, including H3K4me3, H3K27ac, and H3K14ac. Interestingly, T-2 toxin-induced AhR activation also facilitated RNA polymerase II binding to CpG island 2, which may form a transcriptionally active chromatin structure at the promoter and ultimately transactivate CYP1A4. Our findings provide novel insights into the epigenetic regulation of T-2 toxin-induced gene expression.
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Affiliation(s)
- Jun Jiang
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, P.R. China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, P.R. China.,Key Laboratory of Zoonosis of the Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, P.R. China
| | - Jiahui Zhu
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, P.R. China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, P.R. China.,Key Laboratory of Zoonosis of the Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, P.R. China
| | - Qian Liu
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, P.R. China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, P.R. China.,Key Laboratory of Zoonosis of the Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, P.R. China
| | - Tingting Zhang
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, P.R. China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, P.R. China.,Key Laboratory of Zoonosis of the Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, P.R. China
| | - Jikai Wen
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, P.R. China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, P.R. China.,Key Laboratory of Zoonosis of the Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, P.R. China
| | - Jianhong Xia
- Key Laboratory of Regenerative Biology of Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, P.R. China
| | - Yiqun Deng
- Guangdong Provincial Key Laboratory of Protein Function and Regulation in Agricultural Organisms, College of Life Sciences, South China Agricultural University, Guangzhou, P.R. China.,Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, P.R. China.,Key Laboratory of Zoonosis of the Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, P.R. China
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9
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Chaube R, Rawat A, Inbaraj RM, Joy KP. Cloning and characterization of estrogen hydroxylase (cyp1a1 and cyp1b1) genes in the stinging catfish Heteropneustes fossilis and induction of mRNA expression during final oocyte maturation. Comp Biochem Physiol A Mol Integr Physiol 2020; 253:110863. [PMID: 33301890 DOI: 10.1016/j.cbpa.2020.110863] [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: 10/16/2020] [Revised: 11/30/2020] [Accepted: 11/30/2020] [Indexed: 10/22/2022]
Abstract
Estrogen hydroxylases (EHs) are cytochrome P450 Family 1 (Cyp1, Clan 2) proteins involved in estrogen hydroxylations at 2-, 4- or 16- carbon positions to form catecholestrogens. EHs are encoded by CYP1A1, CYP1A2 and CYP1B1 in mammals. In the catfish Heteropneustes fossilis, cyp1a1 and cyp1b1 cDNAs were cloned and characterized from liver and ovary. The cyp1a1 cDNA is 2071 bp long and codes for a 518 amino acids (aa) long protein. The cloned cyp1b1 cDNA is 1927 bp long and codes for a 509 residue protein. The deduced proteins clustered distinctly into teleost Cyp1a1 and Cyp1b1 clades, distinct from the tetrapod clusters and featured common function domains and homology with other teleost proteins. In the qPCR assay, the transcripts were the most abundant in the liver, followed by brain and ovary, and moderate in gill, kidney and muscle. Evidence was presented to show the involvement of the genes in reproduction. Expression of brain and ovarian transcripts showed significant seasonal variations with the highest abundance in the spawning phase. In situ hybridization showed the transcripts in the follicular layer (theca and granulosa) of the ovarian follicles. Periovulatory changes in the expression cyp1a1 and cyp1b1 were obtained during final oocyte maturation (FOM) and ovulation induced by human chorionic gonadotropin (hCG), both in vivo and in vitro, and by 2-hydroxyestradiol-17β (catecholestrogen) in vitro. In the brain, the transcript levels increased with time but in the ovary, the increase was maximal at 16 h and decreased at 24 h. The periovulatory activation of the cyp1 genes was reported in this study and discussed on the basis of complex regulation of FOM and ovulation.
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Affiliation(s)
- R Chaube
- Department of Zoology, Banaras Hindu University, Varanasi 221005, India
| | - A Rawat
- Department of Zoology, Banaras Hindu University, Varanasi 221005, India
| | - R M Inbaraj
- Department of Zoology, Madras Christian College, Chennai 600059, India
| | - K P Joy
- Department of Biotechnology, Cochin University of Science and Technology, Kochi 682022, India.
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10
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Di Consiglio E, Pistollato F, Mendoza-De Gyves E, Bal-Price A, Testai E. Integrating biokinetics and in vitro studies to evaluate developmental neurotoxicity induced by chlorpyrifos in human iPSC-derived neural stem cells undergoing differentiation towards neuronal and glial cells. Reprod Toxicol 2020; 98:174-188. [PMID: 33011216 PMCID: PMC7772889 DOI: 10.1016/j.reprotox.2020.09.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/17/2020] [Accepted: 09/24/2020] [Indexed: 12/19/2022]
Abstract
Human iPSC-derived NSCs undergoing differentiation possess some metabolic competence. CPF entered the cells and was biotrasformed into its two main metabolites (CPFO and TCP). After repeated exposure, very limited bioaccumulation of CPF was observed. Treatment with CPF decreased neurite outgrowth, synapse number and electrical activity. Treatment with CPF increased BDNF levels and the percentage of astrocytes.
For some complex toxicological endpoints, chemical safety assessment has conventionally relied on animal testing. Apart from the ethical issues, also scientific considerations have been raised concerning the traditional approach, highlighting the importance for considering real life exposure scenario. Implementation of flexible testing strategies, integrating multiple sources of information, including in vitro reliable test methods and in vitro biokinetics, would enhance the relevance of the obtained results. Such an approach could be pivotal in the evaluation of developmental neurotoxicity (DNT), especially when applied to human cell-based models, mimicking key neurodevelopmental processes, relevant to human brain development. Here, we integrated the kinetic behaviour with the toxicodynamic alterations of chlorpyrifos (CPF), such as in vitro endpoints specific for DNT evaluation, after repeated exposure during differentiation of human neural stem cells into a mixed culture of neurons and astrocytes. The upregulation of some cytochrome P450 and glutathione S-transferase genes during neuronal differentiation and the formation of the two major CPF metabolites (due to bioactivation and detoxification) supported the metabolic competence of the used in vitro model. The alterations in the number of synapses, neurite outgrowth, brain derived neurotrophic factor, the proportion of neurons and astrocytes, as well as spontaneous electrical activity correlated well with the CPF ability to enter the cells and be bioactivated to CPF-oxon. Overall, our results confirm that combining in vitro biokinetics and assays to evaluate effects on neurodevelopmental endpoints in human cells should be regarded as a key strategy for a quantitative characterization of DNT effects.
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Affiliation(s)
- Emma Di Consiglio
- Istituto Superiore di Sanità, Environment and Health Department, Mechanisms, Biomarkers and Models Unit, Rome, Italy
| | | | | | - Anna Bal-Price
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Emanuela Testai
- Istituto Superiore di Sanità, Environment and Health Department, Mechanisms, Biomarkers and Models Unit, Rome, Italy
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11
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Ye M, Xu M, Fan S, Zhang M, Zhou B, Yang S, Wei W, Ji C, Ji J, Ji F. Protective effects of three propolis-abundant flavonoids against ethanol-induced injuries in HepG2 cells involving the inhibition of ERK1/2-AHR-CYP1A1 signaling pathways. J Funct Foods 2020. [DOI: 10.1016/j.jff.2020.104166] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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12
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Transcriptional responses in newly-hatched Japanese medaka (Oryzias latipes) associated with developmental malformations following diluted bitumen exposure. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2020; 35:100685. [DOI: 10.1016/j.cbd.2020.100685] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 04/08/2020] [Accepted: 04/10/2020] [Indexed: 11/21/2022]
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13
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Doskey CM, Fader KA, Nault R, Lydic T, Matthews J, Potter D, Sharratt B, Williams K, Zacharewski T. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) alters hepatic polyunsaturated fatty acid metabolism and eicosanoid biosynthesis in female Sprague-Dawley rats. Toxicol Appl Pharmacol 2020; 398:115034. [PMID: 32387183 PMCID: PMC7294678 DOI: 10.1016/j.taap.2020.115034] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 04/30/2020] [Accepted: 05/04/2020] [Indexed: 12/16/2022]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent aryl hydrocarbon receptor (AhR) agonist that elicits a broad spectrum of dose-dependent hepatic effects including lipid accumulation, inflammation, and fibrosis. To determine the role of inflammatory lipid mediators in TCDD-mediated hepatotoxicity, eicosanoid metabolism was investigated. Female Sprague-Dawley (SD) rats were orally gavaged with sesame oil vehicle or 0.01-10 μg/kg TCDD every 4 days for 28 days. Hepatic RNA-Seq data was integrated with untargeted metabolomics of liver, serum, and urine, revealing dose-dependent changes in linoleic acid (LA) and arachidonic acid (AA) metabolism. TCDD also elicited dose-dependent differential gene expression associated with the cyclooxygenase, lipoxygenase, and cytochrome P450 epoxidation/hydroxylation pathways with corresponding changes in ω-6 (e.g. AA and LA) and ω-3 polyunsaturated fatty acids (PUFAs), as well as associated eicosanoid metabolites. Overall, TCDD increased the ratio of ω-6 to ω-3 PUFAs. Phospholipase A2 (Pla2g12a) was induced consistent with increased AA metabolism, while AA utilization by induced lipoxygenases Alox5 and Alox15 increased leukotrienes (LTs). More specifically, TCDD increased pro-inflammatory eicosanoids including leukotriene LTB4, and LTB3, known to recruit neutrophils to damaged tissue. Dose-response modeling suggests the cytochrome P450 hydroxylase/epoxygenase and lipoxygenase pathways are more sensitive to TCDD than the cyclooxygenase pathway. Hepatic AhR ChIP-Seq analysis found little enrichment within the regulatory regions of differentially expressed genes (DEGs) involved in eicosanoid biosynthesis, suggesting TCDD-elicited dysregulation of eicosanoid metabolism is a downstream effect of AhR activation. Overall, these results suggest alterations in eicosanoid metabolism may play a key role in TCDD-elicited hepatotoxicity associated with the progression of steatosis to steatohepatitis.
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Affiliation(s)
- Claire M Doskey
- Department of Biochemistry & Molecular Biology, Institute for Integrative Toxicology, Michigan State University, East Lansing, MI 48824, United States
| | - Kelly A Fader
- Department of Biochemistry & Molecular Biology, Institute for Integrative Toxicology, Michigan State University, East Lansing, MI 48824, United States
| | - Rance Nault
- Department of Biochemistry & Molecular Biology, Institute for Integrative Toxicology, Michigan State University, East Lansing, MI 48824, United States
| | - Todd Lydic
- Department of Physiology, Michigan State University, East Lansing, MI 48824, United States
| | - Jason Matthews
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo 0316, Norway
| | - Dave Potter
- Wellington Laboratories Inc., Guelph, Ontario NIG 3M5, Canada
| | - Bonnie Sharratt
- Wellington Laboratories Inc., Guelph, Ontario NIG 3M5, Canada
| | - Kurt Williams
- Department of Pathobiology and Diagnostic Investigation, Michigan State, East Lansing, MI 48824, United States
| | - Tim Zacharewski
- Department of Biochemistry & Molecular Biology, Institute for Integrative Toxicology, Michigan State University, East Lansing, MI 48824, United States.
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Fontao F, von Engelbrechten M, Seilaz C, Sorg O, Saurat JH. Microcomedones in non-lesional acne prone skin New orientations on comedogenesis and its prevention. J Eur Acad Dermatol Venereol 2020; 34:357-364. [PMID: 31465602 DOI: 10.1111/jdv.15926] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 07/25/2019] [Indexed: 11/29/2022]
Abstract
BACKGROUND In non-lesional skin of acne patients, cyanoacrylate skin surface stripping can harvest a structure called microcomedone (MC) which is the earliest phase of comedogenesis; the root of any subsequent clinical lesion and a target for the prevention of acne relapses. More information is needed on the putative biochemical contributors (biomarkers) of comedogenesis expressed in MC. METHODS Proteins expressed in MC were screened by proteomics, immunohistochemistry and Western blotting. The in vitro effects of a comedolytic Silybum marianum fruit extract (SMFE) were studied in sebocyte cultures by RNA-Seq and modulation of CYP1A1 by qPCR and enzymatic activity. MC severity was correlated to lesions counts and keratin expression during 48 weeks in 23 acne patients using a topical comedolytic formulation containing SMFE. RESULTS Two infundibular keratins, K75 and K79, co-localized in MC with the sebocyte progenitor cell marker LRIG1 and were used as a biomarker of comedogenesis for the follow-up of patients. In cultured sebocytes exposed to SMFE (i) transcriptomic analysis showed an up-regulation by a factor of 15 of RNA coding for K75 and (ii) the gene expression and catalytic activity of CYP1A1 under exposure to dioxin was decreased. In the acne patients using SMFE, the MC index in non-lesional skin decreased over time and remained until the 48th week, significantly lower than that of the first week. There was a high correlation between the decrease of MC index and the decrease and stability of the clinical lesions counts over time. Importantly, a low MC index status was found to be associated with a significant higher K75 expression in microcomedones. DISCUSSION These observations provide new orientations on the mechanism of comedogenesis and its prevention. Maintaining a low MC status in non-lesional skin is a sound target for the prevention of acne relapse and a good sentinel of acne remissions.
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Affiliation(s)
- F Fontao
- Clinical Pharmacology and Toxicology Department, University of Geneva, Genève, Switzerland
| | - M von Engelbrechten
- Clinical Pharmacology and Toxicology Department, University of Geneva, Genève, Switzerland
| | - C Seilaz
- Clinical Pharmacology and Toxicology Department, University of Geneva, Genève, Switzerland
| | - O Sorg
- Clinical Pharmacology and Toxicology Department, University of Geneva, Genève, Switzerland
| | - J H Saurat
- Clinical Pharmacology and Toxicology Department, University of Geneva, Genève, Switzerland
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15
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Aromatic hydrocarbon receptor regulates chicken cytochrome P450 1A5 transcription: A novel insight into T-2 toxin-induced gene expression and cytotoxicity in LMH cells. Biochem Pharmacol 2019; 168:319-329. [DOI: 10.1016/j.bcp.2019.07.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 07/23/2019] [Indexed: 12/17/2022]
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16
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Hale MD, Bertucci EM, Rainwater TR, Wilkinson PM, Parrott BB. The impact of maternally derived dioxins on embryonic development and hepatic AHR signaling in a long-lived apex predator. CHEMOSPHERE 2019; 229:489-499. [PMID: 31096085 DOI: 10.1016/j.chemosphere.2019.04.187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 04/23/2019] [Accepted: 04/24/2019] [Indexed: 06/09/2023]
Abstract
Dioxins and related contaminants are highly pervasive in aquatic systems and elicit deleterious effects in exposed organisms. Because dioxins exhibit a proclivity to bioaccumulate, long-lived predatory species are particularly vulnerable to their persistence in the environment. We have previously reported elevated expression of CYP1A2, a biomarker of dioxin exposure, in American alligator embryos collected from the Tom Yawkey Wildlife Center (YWC). This coastal population inhabits a system with historical dioxin contamination associated with industrial activities. Herein, we utilize ecological attributes of the alligator to address the persistence of dioxins and furans in yolk and their potential to drive changes in hepatic function. Specifically, we assess variation in expression of AHR signaling components in embryos and its connection to contaminant levels in matched yolk samples. Compared to a reference population, TEQ levels and total penta-, hexa-, octa-substituted CDDs were elevated at YWC. Contrary to predictions, TEQ levels were not significantly related to hepatic AHR1B or CYP1A2 expression. However, a significant association was detected between expression of both factors and embryo:yolk mass ratios, wherein decreasing embryo mass was negatively associated with CYP1A2 but positively associated with AHR1B. These findings suggest that variation in embryonic metabolism and developmental progression likely influence AHR signaling and dioxin toxicity in alligators and potentially other oviparous species. While dioxin concentrations observed in alligators in this study are lower than historical values reported for other wildlife species inhabiting this system, they indicate the continued presence and possible long-term influence of these contaminants in a high trophic status species.
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Affiliation(s)
- Matthew D Hale
- Savannah River Ecology Laboratory Laboratory, Aiken, SC, USA; Odum School of Ecology, University of Georgia, Athens, GA, USA.
| | - Emily M Bertucci
- Savannah River Ecology Laboratory Laboratory, Aiken, SC, USA; Odum School of Ecology, University of Georgia, Athens, GA, USA
| | - Thomas R Rainwater
- Tom Yawkey Wildlife Center Heritage Preserve, South Carolina Department of Natural Resources, Georgetown, SC, USA; Belle W. Baruch Institute of Coastal Ecology and Forest Science, Clemson University, Georgetown, SC, USA
| | - Philip M Wilkinson
- Tom Yawkey Wildlife Center Heritage Preserve, South Carolina Department of Natural Resources, Georgetown, SC, USA
| | - Benjamin B Parrott
- Savannah River Ecology Laboratory Laboratory, Aiken, SC, USA; Odum School of Ecology, University of Georgia, Athens, GA, USA
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Elsayed HYA, Borroto ET, Pliego AB, Dibarrat JA, Ramirez FR, Chagoyán JCV, Salas NP, Diaz-Albiter H. Sperm Quality in Mouse After Exposure to Low Doses of TCDD. Curr Top Med Chem 2019; 19:931-943. [DOI: 10.2174/1568026619666190520090132] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 12/05/2018] [Accepted: 03/27/2019] [Indexed: 02/07/2023]
Abstract
Background:
In the last decade, the harmful use of dioxin has been demonstrated in human
health and in the whole environment. It is well known among scientists that 2, 3, 7, 8-tetrachloro
dibenzo-p-dioxin (TCDD) is an environmental pollutant that causes endocrine disruption, which causes
male reproductive toxicity.
Objective:
The objective of the present study was to evaluate the toxicity effect of low doses of TCDD
in male CD1 mice.
Materials and Methods:
Three concentrations of TCDD (0.375, 0.75, 1.5 mg / kg) were analyzed and
the effects on spermatozoa were evaluated 10 days after oral administration of the product. As
bioindicators of TCDD toxicity, an exhaustive analysis of several spermatic parameters including
motility, vitality, count, morphology and viability, flow cytometry was used to determine the affected
sperm population by cytotoxicity and apoptosis. In addition, a morphometric analysis of testicles was
performed.
Results:
The results show that the body weight of the treated animals was reduced in medium and high
doses (0.75, 1.5 mg / kg) with respect to the control groups. In the groups treated with TCDD, the
abnormal head of the sperm increased by 52.5% more than the control group. Significant differences in
apoptosis were observed between the negative control and vehicle control, including the median dose
(0.75 mg / kg).
Conclusion:
It is concluded that at these low doses there was an impact on the quality of the mouse
sperm, adding an effect on apoptosis and cytotoxicity of sperm exposed to these doses of TCDD.
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Affiliation(s)
- Heba Yehia Anwar Elsayed
- Centro de Investigacion y Estudios Avanzados de Salud Animal, Facultad de Medicina Veterinaria y Zootecnia Universidad Autonoma del Estado de Mexico, Toluca, Mexico
| | - Esvieta Tenorio Borroto
- Centro de Investigacion y Estudios Avanzados de Salud Animal, Facultad de Medicina Veterinaria y Zootecnia Universidad Autonoma del Estado de Mexico, Toluca, Mexico
| | - Alberto Barbabosa Pliego
- Centro de Investigacion y Estudios Avanzados de Salud Animal, Facultad de Medicina Veterinaria y Zootecnia Universidad Autonoma del Estado de Mexico, Toluca, Mexico
| | - Jorge Acosta Dibarrat
- Centro de Investigacion y Estudios Avanzados de Salud Animal, Facultad de Medicina Veterinaria y Zootecnia Universidad Autonoma del Estado de Mexico, Toluca, Mexico
| | | | - Juan Carlos Vázquez Chagoyán
- Centro de Investigacion y Estudios Avanzados de Salud Animal, Facultad de Medicina Veterinaria y Zootecnia Universidad Autonoma del Estado de Mexico, Toluca, Mexico
| | - Nazario Pescador Salas
- Centro de Investigacion y Estudios Avanzados de Salud Animal, Facultad de Medicina Veterinaria y Zootecnia Universidad Autonoma del Estado de Mexico, Toluca, Mexico
| | - Hector Diaz-Albiter
- Universidad Tecnologica del Valla de Toluca, Estado de Mexico, Toluca, Mexico
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18
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Nynca A, Sadowska A, Paukszto L, Molcan T, Ruszkowska M, Swigonska S, Orlowska K, Myszczynski K, Jastrzebski JP, Ciereszko RE. Temporal changes in the transcriptomic profile of granulosa cells of pigs treated with 2,3,7,8-tetrachlorodibenzo-p-dioxin. Anim Reprod Sci 2019; 207:83-94. [PMID: 31213330 DOI: 10.1016/j.anireprosci.2019.06.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 05/15/2019] [Accepted: 06/04/2019] [Indexed: 01/17/2023]
Abstract
The 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) compound is an environmental chemical adversely affecting reproductive processes. Intracellular TCDD effects are mediated via aryl hydrocarbon receptor (AhR). The aim of the current study was to identify genes linking the AhR pathway with phenotypic consequences of TCDD action in granulosa cells of pigs. By applying multifactorial analysis, with TCDD and incubation time as factors, it was possible to determine temporal changes induced by TCDD in the cell transcriptome. Among the identified 144 differentially expressed genes (DEGs; Padjusted<0.05, log2 fold change (FC)≥1), 111 DEGs were classified as sustained genes (FC values changing between 3 and 24 h). Eighty six DEGs were classified as early genes and only nine as late genes (FC changes observed between 3 and 12 h or 12 and 24 h, respectively). The sustained gene category included genes related to TCDD mechanism of action (AHR, ARNTL, CYP1A1), cell proliferation (TGFβ3), follicular development and ovulation (PTGS2) as well as stress response (NR3C1). The early gene category contained DEGs associated with cell proliferation (DUSP4, TAB1) and cellular response to stress (DHX34). The CYP1A1 gene was the only DEG classified as an early, late and sustained gene. The multifactorial approach allowed for statistically analyzing TCDD-induced changes over time in the gene expression in granulosa cells of pigs. Changes over time in the granulosal transcriptome profile indicated the involvement of stress related molecules in the cellular response to TCDD and TCDD effects on ovulation. The TCDD effects were particularly evident during the early stage of action by this compound.
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Affiliation(s)
- Anna Nynca
- Laboratory of Molecular Diagnostics, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Prawochenskiego 5, 10-720, Olsztyn, Poland.
| | - Agnieszka Sadowska
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719, Olsztyn, Poland.
| | - Lukasz Paukszto
- Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719, Olsztyn, Poland.
| | - Tomasz Molcan
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719, Olsztyn, Poland.
| | - Monika Ruszkowska
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719, Olsztyn, Poland.
| | - Sylwia Swigonska
- Laboratory of Molecular Diagnostics, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Prawochenskiego 5, 10-720, Olsztyn, Poland.
| | - Karina Orlowska
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719, Olsztyn, Poland.
| | - Kamil Myszczynski
- Department of Botany and Nature Protection, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Plac Lodzki 1, 10-727, Olsztyn, Poland.
| | - Jan P Jastrzebski
- Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719, Olsztyn, Poland.
| | - Renata E Ciereszko
- Laboratory of Molecular Diagnostics, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Prawochenskiego 5, 10-720, Olsztyn, Poland; Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowskiego 1A, 10-719, Olsztyn, Poland.
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Tian Y, Wu B, Li X, Jin X, Zhang F, Jiang C, Xu W, Li H, Wang H. The Resveratrol Alleviates the Hepatic Toxicity of CuSO 4 in the Rat. Biol Trace Elem Res 2019; 187:464-471. [PMID: 29980948 DOI: 10.1007/s12011-018-1398-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/24/2018] [Indexed: 02/07/2023]
Abstract
Cu is toxic to humans and other animals. Oxidative stress is an important mechanism involved in Cu toxicity. Resveratrol (RSV) is an antioxidative compound, so could counteract Cu toxicity. The aim of this study was to determine whether RSV protects the liver from the effects of CuSO4. Forty male Sprague-Dawley rats (5 weeks old, 110-120 g) were divided into four groups (n = 10 per group), a control group and groups treated with CuSO4 at a dose of 200 mg/kg body weight (BW), RSV at a dose of 15 mg/kg BW, and CuSO4 at a dose of 200 mg/kg BW and RSV at a dose of 15 mg/kg BW. The treatments were orally administered for 30 days. The livers were removed from the rats at the end of the study, and the cytochrome P450, cytochrome b5, Cu, Fe, Zn, glutathione peroxidase, superoxide dismutase, reactive oxygen species, aspartate aminotransferase, and alanine aminotransferase concentrations in the livers were determined. CuSO4 decreased the BW, liver weight, and cytochrome P450, cytochrome b5, Fe, Zn, glutathione peroxidase, and superoxide dismutase concentrations but increased the Cu, aspartate aminotransferase, alanine aminotransferase, and reactive oxygen species concentrations relative to the control group. RSV alleviated the toxic effects of CuSO4 on the liver, indicating that RSV attenuates CuSO4-induced liver injury by decreasing the liver transaminase concentration and oxidative stress, promoting antioxidative activity and cytochrome P450 enzymes, and maintaining balance in the trace element concentrations. The results indicate that RSV could be used to treat CuSO4 toxicity.
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Affiliation(s)
- Yaping Tian
- Department of Dermatology and Venerology of the First Hospital, Jilin University, Changchun, 130021, China
| | - Bing Wu
- Department of Neurosurgery of China-Japan Union Hospital, Jilin University, Changchun, 130033, China
- Key Laboratory of Radiobiology (Ministry of Health) of Public Health, Jilin University, Changchun, 130033, China
| | - Xiaoping Li
- Department of Pediatric Endocrinology of the First Hospital, Jilin University, Changchun, 130021, China
| | - Xuefei Jin
- Department of Urology of China-Japan Union Hospital, Jilin University, Changchun, 130033, China
| | - Fuqiang Zhang
- Science and Research Center of China-Japan Union Hospital, Jilin University, Changchun, 130033, China
| | - Chunyan Jiang
- Key Laboratory of Hormones and Development (Ministry of Health), Tianjin Key Laboratory of Metabolic Diseases, Tianjin Metabolic Diseases Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin, 300070, China
| | - Wenzhou Xu
- Department of Stomatology, Stomatological Hospital, Jilin University, Changchun, 130021, China
| | - Hang Li
- Department of Hepatobiliary and pancreatic surgery, China-Japan Union Hospital, Jilin University, Changchun, 130033, China
| | - Heyuan Wang
- Department of Endocrinology and Metabolism of the First Hospital, Jilin University, Changchun, 130021, China.
- Department of Immunology in College of Basic Medical Sciences, Jilin University, Changchun, 130021, China.
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20
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V. Yurchenko V, A. Morozov A. Intra-annual variability of hepatic ethoxyresorufin-O-deethylase activity in freshwater bream Abramis brama. BIOL RHYTHM RES 2018. [DOI: 10.1080/09291016.2018.1484871] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Victoria V. Yurchenko
- Laboratory of Physiology and Toxicology of Aquatic Animals, Papanin Institute for Biology of Inland Waters Russian Academy of Sciences, Borok, Russia
| | - Alexey A. Morozov
- Laboratory of Physiology and Toxicology of Aquatic Animals, Papanin Institute for Biology of Inland Waters Russian Academy of Sciences, Borok, Russia
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21
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McMillan DM, Tyndale RF. CYP-mediated drug metabolism in the brain impacts drug response. Pharmacol Ther 2018; 184:189-200. [DOI: 10.1016/j.pharmthera.2017.10.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Abstract
The radiation-induced bystander effect (RIBE) is the initiation of biological end points in cells (bystander cells) that are not directly traversed by an incident-radiation track, but are in close proximity to cells that are receiving the radiation. RIBE has been indicted of causing DNA damage via oxidative stress, besides causing direct damage, inducing tumorigenesis, producing micronuclei, and causing apoptosis. RIBE is regulated by signaling proteins that are either endogenous or secreted by cells as a means of communication between cells, and can activate intracellular or intercellular oxidative metabolism that can further trigger signaling pathways of inflammation. Bystander signals can pass through gap junctions in attached cell lines, while the suspended cell lines transmit these signals via hormones and soluble proteins. This review provides the background information on how reactive oxygen species (ROS) act as bystander signals. Although ROS have a very short half-life and have a nanometer-scale sphere of influence, the wide variety of ROS produced via various sources can exert a cumulative effect, not only in forming DNA adducts but also setting up signaling pathways of inflammation, apoptosis, cell-cycle arrest, aging, and even tumorigenesis. This review outlines the sources of the bystander effect linked to ROS in a cell, and provides methods of investigation for researchers who would like to pursue this field of science.
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Affiliation(s)
- Humaira Aziz Sawal
- Healthcare Biotechnology Department, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad
| | - Kashif Asghar
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan
| | - Matthias Bureik
- Health Science Platform, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
| | - Nasir Jalal
- Health Science Platform, Department of Molecular and Cellular Pharmacology, Tianjin University, Tianjin, China
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Aguirre-Martínez GV, Reinardy HC, Martín-Díaz ML, Henry TB. Response of gene expression in zebrafish exposed to pharmaceutical mixtures: Implications for environmental risk. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2017; 142:471-479. [PMID: 28458231 DOI: 10.1016/j.ecoenv.2017.04.038] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 04/15/2017] [Accepted: 04/17/2017] [Indexed: 05/26/2023]
Abstract
Complex mixtures of pharmaceutical chemicals in surface waters indicate potential for mixture effects in aquatic organisms. The objective of the present study was to evaluate whether effects on target gene expression and enzymatic activity of individual substances at environmentally relevant concentrations were additive when mixed. Expression of zebrafish cytochrome P4501A (cyp1a) and vitellogenin (vtg) genes as well as activity of ethoxyresorufin-O-deethylase (EROD) were analyzed after exposure (96h) to caffeine-Caf, ibuprofen-Ibu, and carbamazepine-Cbz (0.05 and 5µM), tamoxifen-Tmx (0.003 and 0.3µM), and after exposure to pharmaceutical mixtures (low mix: 0.05µM of Caf, Ibu, Cbz and 0.003µM of Tmx, and high mix: 5µM of Caf, Ibu, Cbz and 0.3µM of Tmx). Pharmaceuticals tested individually caused significant down regulation of both cyp1a and vtg, but EROD activity was not affected. Exposure to low mix did not cause a significant change in gene expression; however, the high mix caused significant up-regulation of cyp1a but did not affect vtg expression. Up-regulation of cyp1a was consistent with induction of EROD activity in larvae exposed to high mix. The complex mixture induced different responses than those observed by the individual substances. Additive toxicity was not supported, and results indicate the need to evaluate complex mixtures rather than models based on individual effects, since in environment drugs are not found in isolation and the effects of their mixtures is poorly understood.
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Affiliation(s)
- Gabriela V Aguirre-Martínez
- School of Biomedical and Biological Science, 411 Davy Building, University of Plymouth, Drake Circus, Plymouth PL4 8AA, United Kingdom; Health Science Faculty, Arturo Prat University, Casilla 121, 1110939 Iquique, Chile; Andalusian Center of Marine Science and Technology (CACYTMAR), Campus Universitario Puerto Real, 11510 Puerto Real, Cádiz, Spain.
| | - Helena C Reinardy
- School of Biomedical and Biological Science, 411 Davy Building, University of Plymouth, Drake Circus, Plymouth PL4 8AA, United Kingdom; Department of Arctic Technology, UNIS, Longyearbyen N-9171, Norway
| | - M Laura Martín-Díaz
- Andalusian Center of Marine Science and Technology (CACYTMAR), Campus Universitario Puerto Real, 11510 Puerto Real, Cádiz, Spain; Facultad Ciencias del Mar y Ambientales, Universidad de Cádiz, Campus de Excelencia Internacional del Mar (CEIMAR), Polígono Río San Pedro s/n. P. Real, Cádiz, Spain
| | - Theodore B Henry
- School of Biomedical and Biological Science, 411 Davy Building, University of Plymouth, Drake Circus, Plymouth PL4 8AA, United Kingdom; School of Life Sciences, Heriot-Watt University, 3.05 William Perkin Building, Edinburgh EH14 4AS, United Kingdom; Center for Environmental Biotechnology, University of Tennessee, Knoxville TN 37996, USA; Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN 37996, USA.
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Wu X, Yang J, Morisseau C, Robertson LW, Hammock B, Lehmler HJ. 3,3',4,4',5-Pentachlorobiphenyl (PCB 126) Decreases Hepatic and Systemic Ratios of Epoxide to Diol Metabolites of Unsaturated Fatty Acids in Male Rats. Toxicol Sci 2016; 152:309-22. [PMID: 27208083 PMCID: PMC4960907 DOI: 10.1093/toxsci/kfw084] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Disruption of the homeostasis of oxygenated regulatory lipid mediators (oxylipins), potential markers of exposure to aryl hydrocarbon receptor (AhR) agonists, such as 3,3',4,4',5-pentachlorobiphenyl (PCB 126), is associated with a range of diseases, including nonalcoholic fatty liver disease and nonalcoholic steatohepatitis. Here we test the hypothesis that PCB 126 exposure alters the levels of oxylipins in rats. Male Sprague-Dawley rats (5-weeks old) were treated over a 3-month period every 2 weeks with intraperitoneal injections of PCB 126 in corn oil (cumulative doses of 0, 19.8, 97.8, and 390 µg/kg b.w.; 6 injections total). PCB 126 treatment caused a reduction in growth rates at the highest dose investigated, a dose-dependent decrease in thymus weights, and a dose-dependent increase in liver weights. Liver PCB 126 levels increased in a dose-dependent manner, while levels in plasma were below or close to the detection limit. The ratios of several epoxides to diol metabolites formed via the cytochrome P450 (P450) monooxygenase/soluble epoxide hydrolase (sEH) pathway from polyunsaturated fatty acids displayed a dose-dependent decrease in the liver and plasma, whereas levels of oxylipins formed by other metabolic pathways were generally not altered by PCB 126 treatment. The effects of PCB 126 on epoxide-to-diol ratios were associated with an increased CYP1A activity in liver microsomes and an increased sEH activity in liver cytosol and peroxisomes. These results suggest that oxylipins are potential biomarkers of exposure to PCB 126 and that the P450/sEH pathway is a therapeutic target for PCB 126-mediated hepatotoxicity that warrants further attention.
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Affiliation(s)
- Xianai Wu
- *Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa
| | - Jun Yang
- Department of Entomology and Nematology, UC Davis Comprehensive Cancer Center, University of California, Davis, California
| | - Christophe Morisseau
- Department of Entomology and Nematology, UC Davis Comprehensive Cancer Center, University of California, Davis, California
| | - Larry W Robertson
- *Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa
| | - Bruce Hammock
- Department of Entomology and Nematology, UC Davis Comprehensive Cancer Center, University of California, Davis, California
| | - Hans-Joachim Lehmler
- *Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa
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Perepechaeva ML, Kolosova NG, Stefanova NA, Fursova AZ, Grishanova AY. The influence of changes in expression of redox-sensitive genes on the development of retinopathy in rats. Exp Mol Pathol 2016; 101:124-32. [PMID: 27466007 DOI: 10.1016/j.yexmp.2016.07.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 06/07/2016] [Accepted: 07/19/2016] [Indexed: 01/24/2023]
Abstract
Age-related macular degeneration (AMD) is a complex multifactorial disease of the elderly, with unclear pathogenesis; AMD is the leading cause of blindness. One of the destructive processes in AMD is oxidative stress, which leads to an imbalance in the processes responsible for production and detoxification of reactive oxygen species. The aryl hydrocarbon receptor (AhR) signaling pathway can participate in the development of oxidative stress, but the main regulator of antioxidant defense is nuclear factor, erythroid derived 2 (Nrf2). AhR-dependent oxidative stress can be attenuated by activation of Nrf2, and defects in the Nrf2 signaling pathway can increase sensitivity of the cell to oxidative stress. Our aim was to determine the role of the pro-oxidant (AhR-dependent) and antioxidant (Nrf2-dependent) systems in the pathogenesis of AMD using rats of OXYS strain and of OXYSb substrain with signs of AMD-like retinopathy of varying severity. We compared the retinal levels of mRNA expression of Nrf2- and AhR-dependent redox-sensitive systems between 1-, 3-, and 12- month-old senescence-accelerated OXYS rats (have been shown to be a valid experimental model of AMD) and the rat substrain OXYSb, which shows low morbidity of AMD. We uncovered interstrain differences in the expression of Nrf2 and Nrf2-dependent genes (glutathione S-reductase [Gsr] and heme oxygenase 1 [Hmox1]), in the expression of AhR-dependent genes (cytochrome P450 1A2 [Cyp1a2] and cytochrome P450 1B1 [Cyp1b1]), and in the NADPH-quinone oxidoreductase (Nqo1) expression, which is controlled by both AhR and Nrf2. Binding of AhR and Nrf2 proteins to the regulatory regions of AhR and Nrf2 genes, respectively, was detected by chromatin immunoprecipitation in the retina of 1-, 3-, and 12-month-old OXYS, OXYSb, and Wistar (control) rats. We compared the strength of DNA-protein interactions of AhR and Nrf2 with regulatory sequences and found that the level of autoupregulation of the AhR gene was higher in the retina of 1-month-old OXYSb rats in comparison with OXYS rats. An imbalance between pro-oxidant (AhR-dependent) and antioxidant (Nrf2-dependent) systems may play a crucial role in the onset and/or progression of AMD.
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Affiliation(s)
- M L Perepechaeva
- Institute of Molecular Biology and Biophysics, Timakova Str. 2/12, Novosibirsk 630117, Russia.
| | - N G Kolosova
- Institute of Molecular Biology and Biophysics, Timakova Str. 2/12, Novosibirsk 630117, Russia; Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Lavrentiev Ave. 10, Novosibirsk 630090, Russia; Novosibirsk State University, Pirogova Str. 2, Novosibirsk 630090, Russia.
| | - N A Stefanova
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Lavrentiev Ave. 10, Novosibirsk 630090, Russia.
| | - A Zh Fursova
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Lavrentiev Ave. 10, Novosibirsk 630090, Russia.
| | - A Y Grishanova
- Institute of Molecular Biology and Biophysics, Timakova Str. 2/12, Novosibirsk 630117, Russia.
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Hankinson O. The role of AHR-inducible cytochrome P450s in metabolism of polyunsaturated fatty acids. Drug Metab Rev 2016; 48:342-50. [PMID: 27358009 DOI: 10.1080/03602532.2016.1197240] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The environmental pollutant 2,3,7,8-tetrachlorodibenzo-ρ-dioxin (TCDD) is the prototype of a large number of non-genotoxic carcinogens, dietary phytochemicals and endogenous metabolites that act via binding the aryl hydrocarbon receptor (AHR). The TCDD-liganded AHR massively upregulates CYP1A1, CYP1A2 and CYP1B1 in many mammalian organs. We demonstrated that TCDD treatment markedly increases the levels of several epoxides and diol metabolites of the epoxides of both ω-6 and ω-3 polyunsaturated fatty acids (PUFA) in the liver and lungs of mice, in an aryl hydrocarbon receptor-dependent fashion, and most likely via the activities of the CYP1 family members. ω-6 Epoxides are known to stimulate tumor growth, angiogenesis, and metastasis in mice. Interestingly, ω-3 epoxides have the opposite effect on these parameters. TCDD and other AHR agonists may, therefore, impact angiogenesis, growth and metastasis of tumors in either a positive or negative way, depending on the relative levels of ω -6 epoxides and ω-3 epoxides generated in the host and/or tumor cells. This is of potential relevance to carcinogenesis by AHR agonists in the human, since the human population is exposed to widely varying ω-6: ω-3 PUFA ratios in the diet.
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Li R, Song M, Li Z, Li Y, Watanabe G, Nagaoka K, Taya K, Li C. 4-Nitrophenol exposure alters the AhR signaling pathway and related gene expression in the rat liver. J Appl Toxicol 2016; 37:150-158. [DOI: 10.1002/jat.3332] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Revised: 03/09/2016] [Accepted: 03/11/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Ruonan Li
- Jiangsu Provincial Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology; Nanjing Agricultural University; Nanjing China
| | - Meiyan Song
- Jiangsu Provincial Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology; Nanjing Agricultural University; Nanjing China
| | - Zhi Li
- Jiangsu Provincial Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology; Nanjing Agricultural University; Nanjing China
| | - Yansen Li
- Jiangsu Provincial Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology; Nanjing Agricultural University; Nanjing China
| | - Gen Watanabe
- Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture; Tokyo University of Agriculture and Technology; Tokyo Japan
- Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences; Gifu University; Gifu Japan
| | - Kentaro Nagaoka
- Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture; Tokyo University of Agriculture and Technology; Tokyo Japan
- Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences; Gifu University; Gifu Japan
| | - Kazuyoshi Taya
- Jiangsu Provincial Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology; Nanjing Agricultural University; Nanjing China
- Laboratory of Veterinary Physiology, Cooperative Department of Veterinary Medicine, Faculty of Agriculture; Tokyo University of Agriculture and Technology; Tokyo Japan
| | - Chunmei Li
- Jiangsu Provincial Key Laboratory of Gastrointestinal Nutrition and Animal Health, College of Animal Science and Technology; Nanjing Agricultural University; Nanjing China
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Palanisamy K, Krishnaswamy R, Paramasivan P, Chih-Yang H, Vishwanadha VP. Eicosapentaenoic acid prevents TCDD-induced oxidative stress and inflammatory response by modulating MAP kinases and redox-sensitive transcription factors. Br J Pharmacol 2015; 172:4726-40. [PMID: 26177858 DOI: 10.1111/bph.13247] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Revised: 06/01/2015] [Accepted: 07/01/2015] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE Oxidative stress and subsequent activation of inflammatory responses is a widely accepted consequence of exposure to environmental toxins. TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin), a well-known environmental toxin, exerts its toxicity through many signalling mechanisms, with liver being the principal organ affected. However, an effective antidote to TCDD-induced toxicity is unknown. The present study evaluated the effect of eicosapentaenoic acid (EPA), an n3 fatty acid, on TCDD-induced toxicity. EXPERIMENTAL APPROACH In cultures of HepG2 cells, the EPA/AA ratio was determined using gas chromatography, oxidative stress and inflammatory responses through reactive oxygen species (ROS) levels, antioxidant status, [Ca(2+) ]i , nuclear migration of two redox-sensitive transcription factors, NF-κB p65 and Nrf-2, expression of MAP kinase (p-Erk, p-p38), NF-κB p65, COX-2 and Nrf-2. Cellular changes in ΔΨm, acidic vesicular organelle formation, cell cycle analysis and scanning electron microscopy analysis were performed. KEY RESULTS EPA offered significant cytoprotection by increasing EPA/AA ratios in cell membranes, inhibiting ROS generation, enhancing antioxidant status and modulating nuclear translocation of redox-sensitive transcription factors (NF-κB p65 and Nrf-2) and expression of NF-κB p65, COX-2 and Nrf-2. Furthermore, TCDD-induced upstream events of MAPK phosphorylation, the increase in [Ca(2+) ]i levels and cell surface changes in microvilli were significantly inhibited by EPA. EPA treatment maintained ΔΨm and prevented formation of acidic vesicular organelles. CONCLUSION AND IMPLICATIONS The present study demonstrates for the first time some underlying molecular mechanisms of cytoprotection exerted by EPA against TCDD-induced oxidative stress and inflammatory responses.
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Affiliation(s)
- Kalaiselvi Palanisamy
- Department of Biotechnology, School of Biotechnology and Genetic Engineering, Bharathiar University, Coimbatore, Tamil Nadu, India.,Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan
| | - Rajashree Krishnaswamy
- Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, Tamil Nadu, India
| | - Poornima Paramasivan
- Department of Biotechnology, School of Biotechnology and Genetic Engineering, Bharathiar University, Coimbatore, Tamil Nadu, India
| | - Huang Chih-Yang
- Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan.,Graduate Institute of Chinese Medical Science, China Medical University, Taichung, Taiwan.,Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan
| | - Vijaya Padma Vishwanadha
- Department of Biotechnology, School of Biotechnology and Genetic Engineering, Bharathiar University, Coimbatore, Tamil Nadu, India.,Graduate Institute of Basic Medical Science, China Medical University, Taichung, Taiwan.,Department of Biotechnology, Asia University, Taichung, Taiwan
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Human urinary biomarkers of dioxin exposure: Analysis by metabolomics and biologically driven data dimensionality reduction. Toxicol Lett 2014; 230:234-43. [DOI: 10.1016/j.toxlet.2013.10.031] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 10/16/2013] [Accepted: 10/26/2013] [Indexed: 12/31/2022]
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Zou JG, Ma YT, Xie X, Yang YN, Pan S, Adi D, Liu F, Chen BD. The association between CYP1A1 genetic polymorphisms and coronary artery disease in the Uygur and Han of China. Lipids Health Dis 2014; 13:145. [PMID: 25189712 PMCID: PMC4175619 DOI: 10.1186/1476-511x-13-145] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 09/02/2014] [Indexed: 11/25/2022] Open
Abstract
Background The cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) gene is expressed in the vascular endothelium, which metabolizes arachidonic acid into 20-hydroxyeicosatetraenoic acid (20-HETE) and epoxyeicosatrienoic acids (EETs). 20-HETE mediates cardiovascular homeostasis and growth response in vascular smooth muscle cells (VSMCs) as well as the anti-platelet effect. EETs are potent endogenous vasodilators and inhibitors of vascular inflammation. This study assessed the association between human CYP1A1 gene polymorphisms and coronary artery disease (CAD) in the Uygur and Han in China. Methods Two independent case–control studies that recruited Han (389 patients with CAD and 411 controls) and Uygur participants (293 patients with CAD and 408 controls) analyzed the relationship between CYP1A1 single nucleotide polymorphisms (SNPs: rs4886605, rs12441817, rs4646422 and rs1048943) and CAD. All patients with CAD and controls were genotyped for the four SNPs of CYP1A1 using TaqMan SNP genotyping assays. Results In the Uygur group, the distribution of the dominant model(CC vs CT + TT) of rs4886605 for the total sample and the males was significantly different between CAD patients and control participants (P = 0.001 and P = 0.012, respectively), The difference remained significant after a multivariate adjustment (P = 0.018, P = 0.015, respectively). The rs12441817 was also associated with CAD in a dominant model for all participants (P = 0.003) and men (P = 0.012), and the difference remained significant after a multivariate adjustment (P = 0.016, P = 0.002, respectively). However, we did not observe differences in the Uygur females and Han group with regard to the allele frequency or genotypic distribution of rs4886605 and rs12441817 between patients with CAD and control participants. Patients with CAD did not significantly differ from the control participants with regard to the distributions of rs4646422 and rs1048943 genotypes, the dominant model, the recessive model, or allele frequency in the Han and Uygur groups. Conclusion Both rs4886605 and rs12441817 SNPs of the CYP1A1 gene are associated with CAD in the Uygur population of China.
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Affiliation(s)
| | - Yi-Tong Ma
- Department of Cardiology, First Affiliated Hospital of Xinjiang Medical University, Urumqi 830054, People's Republic of China.
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Bonfanti P, Comelli F, Assi L, Casati L, Colciago A, Villa S, Santagostino A, Costa B, Colombo A. Responsiveness of hepatic and cerebral cytochrome P450 in rat offspring prenatally and lactationally exposed to a reconstituted PCB mixture. ENVIRONMENTAL TOXICOLOGY 2014; 29:856-866. [PMID: 22987612 DOI: 10.1002/tox.21812] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 07/27/2012] [Accepted: 08/04/2012] [Indexed: 06/01/2023]
Abstract
Perinatal polychlorinated biphenyl (PCB) exposures still remain a serious health concern because offspring receive PCB burden from mother during vulnerable processes of development. Since cytochrome P450 (CYP) represents a toxicological endpoint, in the present study, representing an extended investigation of a previous multitasked one, we explored the long-term responsiveness of CYP1A and CYP2B isoforms by Western blot analysis in liver and whole brain of lactating (PN12), weaning (PN21), and adult offspring (PN60) rats prenatally and lactationally exposed to a reconstituted PCB mixture (RM) of noncoplanar PCB138, 153, 180, and coplanar PCB126 congeners. We chose highly chlorinated PCBs instead of lower chlorinated one, because their recalcitrance to biotransformation makes easy their accumulation/persistence in tissues and breast milk. Dioxin-like congener PCB126 binding aryl hydrocarbon receptor (AHR) is responsible of many toxic effects. Pregnant Sprague-Dawley dams with high affinity AHR received subcutaneous injection of RM (10 mg/kg body weight) daily during gestation (days 15-19) and twice a week during breast-feeding. The results evidenced a transfer of PCBs to neonates through milk and a significant responsiveness of hepatic CYP in both mothers and offspring. In liver of exposed progeny, CYP isoforms exhibited a significant increment at PN12 (70% over control) and at PN21 (270% over control). Contrary to dams, in adult PCB offspring CYP levels showed a decline up to values similar to those of control. This transient developmental responsiveness of CYP isoforms in offspring liver reflects roughly the time course of hepatic PCB levels previously reported. Even if congeners were detected in brain, we failed in evidencing a responsiveness of CYP isoforms probably because of region-specific CYP expression in this organ. In conclusion, induction of offspring hepatic CYP is index of liver PCB burden, and despite the insensitivity of whole brain CYP we cannot exclude brain vulnerability toward PCB. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 856-866, 2014.
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Affiliation(s)
- Patrizia Bonfanti
- Dipartimento di Scienze dell'Ambiente e del Territorio, Università di Milano Bicocca, P.zza della Scienza 1, 20126 Milano, Italy
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The Mitochondria-Targeted Antioxidant SkQ1 Downregulates Aryl Hydrocarbon Receptor-Dependent Genes in the Retina of OXYS Rats with AMD-Like Retinopathy. J Ophthalmol 2014; 2014:530943. [PMID: 25132985 PMCID: PMC4123489 DOI: 10.1155/2014/530943] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 07/01/2014] [Indexed: 12/14/2022] Open
Abstract
The mitochondria-targeted antioxidant SkQ1 is a novel drug thought to retard development of age-related diseases. It has been shown that SkQ1 reduces clinical signs of retinopathy in senescence-accelerated OXYS rats, which are a known animal model of human age-related macular degeneration (AMD). The aim of this work was to test whether SkQ1 affects transcriptional activity of AhR (aryl hydrocarbon receptor) and Nrf2 (nuclear factor erythroid 2-related factor 2), which are considered as AMD-associated genes in the retina of OXYS and Wistar rats. Our results showed that only AhR and AhR-dependent genes were sensitive to SkQ1. Dietary supplementation with SkQ1 decreased the AhR mRNA level in both OXYS and Wistar rats. At baseline, the retinal Cyp1a1 mRNA level was lower in OXYS rats. SkQ1 supplementation decreased the Cyp1a1 mRNA level in Wistar rats, but this level remained unchanged in OXYS rats. Baseline Cyp1a2 and Cyp1b1 mRNA expression was stronger in OXYS than in Wistar rats. In the OXYS strain, Cyp1a2 and Cyp1b1 mRNA levels decreased as a result of SkQ1 supplementation. These data suggest that the Cyp1a2 and Cyp1b1 enzymes are involved in the pathogenesis of AMD-like retinopathy of OXYS rats and are possible therapeutic targets of SkQ1.
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Helldén A, Madadi P. Pregnancy and pharmacogenomics in the context of drug metabolism and response. Pharmacogenomics 2014; 14:1779-91. [PMID: 24192125 DOI: 10.2217/pgs.13.176] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
It is well-known that profound physiological and biochemical changes occur throughout the course of pregnancy. At the same time, the role of pharmacogenomics in modulating the metabolism and response profile to numerous medications has been elucidated. Yet, the clinical impact of pharmacogenomics during pregnancy is less well understood. We present an overview of factors modulating the pharmacokinetics and pharmacodynamics of medications throughout the time span of pregnancy while providing insights on how pharmacogenomics may contribute to interindividual variability in drug metabolism and response amongst pregnant women.
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Affiliation(s)
- Anders Helldén
- Division of Clinical Pharmacology & Toxicology, Department of Pediatrics, Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada
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The relationship between dioxin congeners in the breast milk of Vietnamese women and sister chromatid exchange. Int J Mol Sci 2014; 15:7485-99. [PMID: 24786289 PMCID: PMC4057685 DOI: 10.3390/ijms15057485] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 04/11/2014] [Accepted: 04/14/2014] [Indexed: 11/16/2022] Open
Abstract
The aim of this study was to clarify the relationship between dioxin concentrations in breast milk and the sister chromatid exchange (SCE) frequency in women from herbicide-sprayed and non sprayed areas. Blood samples were taken from 21 women with high TCDD (tetrachlorodibenzo-p-dioxin) levels from sprayed areas, 23 women with moderate TCDD levels from sprayed areas, and 19 women from non sprayed areas to determine their SCE frequency. The SCE frequencies for the high and moderate TCDD groups from the sprayed area and for the non sprayed area group were 2.40, 2.19, and 1.48 per cell, respectively. Multiple regression analysis showed that the standardized β values for 1,2,3,6,7,8-hexaCDD (β = 0.60), 1,2,3,4,6,7,8-heptaCDD (β = 0.64), and octaCDD (β = 0.65) were higher than those for TCDD (β = 0.34) and 1,2,3,7,8-pentaCDD (β = 0.42). The adjusted R² value for polyCDDs (R² = 0.38) was higher than that for polyCDD toxic equivalents (TEQ (toxic equivalents); R² = 0.23). This study therefore shows that levels of hexa-, hepta-, and octaCDD, which were previously regarded as being less toxic than TCDD, are closely related to SCE frequency and that the level of dioxin (pg/g lipid) is potentially more useful as an indicator than TEQ value for explaining SCE frequency.
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Diani-Moore S, Ma Y, Gross SS, Rifkind AB. Increases in levels of epoxyeicosatrienoic and dihydroxyeicosatrienoic acids (EETs and DHETs) in liver and heart in vivo by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and in hepatic EET:DHET ratios by cotreatment with TCDD and the soluble epoxide hydrolase inhibitor AUDA. Drug Metab Dispos 2013; 42:294-300. [PMID: 24311719 DOI: 10.1124/dmd.113.055368] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The environmental toxin and carcinogen 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, dioxin) binds and activates the transcription factor aryl hydrocarbon receptor (AHR), inducing CYP1 family cytochrome P450 enzymes. CYP1A2 and its avian ortholog CYP1A5 are highly active arachidonic acid epoxygenases. Epoxygenases metabolize arachidonic acid to four regioisomeric epoxyeicosatrienoic acids (EETs) and selected monohydroxyeicosatetraenoic acids (HETEs). EETs can be further metabolized by epoxide hydrolases to dihydroxyeicosatrienoic acids (DHETs). As P450-arachidonic acid metabolites affect vasoregulation, responses to ischemia, inflammation, and metabolic disorders, identification of their production in vivo is needed to understand their contribution to biologic effects of TCDD and other AHR activators. Here we report use of an acetonitrile-based extraction procedure that markedly increased the yield of arachidonic acid products by lipidomic analysis over a standard solid-phase extraction protocol. We show that TCDD increased all four EETs (5,6-, 8,9-, 11,12-, and 14,15-), their corresponding DHETs, and 18- and 20-HETE in liver in vivo and increased 5,6-EET, the four DHETs, and 18-HETE in heart, in a chick embryo model. As the chick embryo heart lacks arachidonic acid-metabolizing activity, the latter findings suggest that arachidonic acid metabolites may travel from their site of production to a distal organ, i.e., heart. To determine if the TCDD-arachidonic acid-metabolite profile could be altered pharmacologically, chick embryos were treated with TCDD and the soluble epoxide hydrolase inhibitor 12-(3-adamantan-1-yl-ureido)-dodecanoic acid (AUDA). Cotreatment with AUDA increased hepatic EET-to-DHET ratios, indicating that the in vivo profile of P450-arachidonic acid metabolites can be modified for potential therapeutic intervention.
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Madanayake TW, Lindquist IE, Devitt NP, Mudge J, Rowland AM. A transcriptomic approach to elucidate the physiological significance of human cytochrome P450 2S1 in bronchial epithelial cells. BMC Genomics 2013; 14:833. [PMID: 24279958 PMCID: PMC3884200 DOI: 10.1186/1471-2164-14-833] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 11/21/2013] [Indexed: 12/14/2022] Open
Abstract
Background Cytochrome P450 2S1 (CYP2S1) is an orphan P450 with an unknown biological function. Data from our laboratory and others suggest that CYP2S1 may have an important physiological role in modulating the synthesis and metabolism of bioactive lipids including prostaglandins and retinoids. CYP2S1 expression is elevated in multiple epithelial-derived cancers as well as in the chronic hyperproliferative disease psoriasis. Whether CYP2S1 expression in proliferative disease is protective, detrimental, or neutral to disease progression remains to be determined. Two human bronchial epithelial cells (BEAS-2B) were constructed to represent chronic depletion of CYP2S1 using short-hairpin RNA (shRNA) silencing directed toward the 3’UTR (759) and exon 3 (984) of the CYP2S1 gene and compared with a non-targeting shRNA control (SCRAM). Both CYP2S1 mRNA and protein were depleted by approximately 75% in stable cell lines derived from both targeted shRNA constructs (759 and 984). To elucidate the biological significance of CYP2S1, we analyzed transcriptome alterations in response to CYP2S1 depletion in human lung cells. Results RNA-sequencing (RNA-seq) analysis was performed to compare the transcriptome of the control (SCRAM) and the CYP2S1-depleted (759) BEAS-2B cell lines. Transcriptomes of the replicates from the two cell lines were found to be distinct populations as determined using Principal Component Analysis and hierarchical clustering. Approximately 1000 genes were differentially expressed in response to CYP2S1 depletion. Consistent with our previous phenotypes, DAVID analysis revealed altered regulation in key pathways implicated in cell proliferation and migration. Transcriptomic profiles were also consistent with the metabolism of proposed endogenous substrates. Pathway analysis also revealed significant expression changes within mTOR signaling, a critical pathway in cell growth. To determine whether these changes manifest as altered cell size, cell diameter and volume were calculated, revealing that CYP2S1 depletion promotes cell growth in BEAS-2B cells. Conclusions These data suggest that pathway analysis of sequence-based gene expression is a powerful method to identify pathways and phenotypic alterations in response to changes in orphan enzyme expression. Our results suggest a novel role for CYP2S1-mediated metabolism in modulating BEAS-2B cell size. These findings warrant further studies on CYP2S1 regulated pathways to elucidate potential substrates of CYP2S1.
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Affiliation(s)
- Thushara W Madanayake
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, NM 88003, USA.
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Development of cardiac hypertrophy by sunitinib in vivo and in vitro rat cardiomyocytes is influenced by the aryl hydrocarbon receptor signaling pathway. Arch Toxicol 2013; 88:725-38. [PMID: 24247421 DOI: 10.1007/s00204-013-1159-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 11/05/2013] [Indexed: 12/23/2022]
Abstract
Sunitinib (SUN) is a new tyrosine kinase inhibitor that possesses both anti-angiogenic and anti-tumor activities. Although SUN has improved survival rate in cancer patients, cardiotoxicity has been reported as a significant side effect. Several studies suggested a role for the aryl hydrocarbon receptor (AhR) and its regulated genes such as cytochrome P4501A1 (CYP1A1) in the pathogenesis of heart failure and cardiac hypertrophy. To test the hypothesis that SUN induces cardiac hypertrophy through the modulation of AhR, Wistar albino rats were treated for 15 and 30 days with increasing doses of SUN (25, 50, and 100 mg/kg), whereas at the in vitro level, rat cardiomyocyte H9c2 cells were incubated with SUN (1, 2.5, and 5 μM). Thereafter, cardiac hypertrophy parameters were determined at the biochemical, histopathology, and gene expression levels. SUN treatment causes increase in cardiac enzymes, changes in histopathology, and induction in several hypertrophic markers. This was associated with proportional increase in the CYP1A1 gene in a concentration- and time-dependent manner. The direct involvement of AhR in the SUN-induced cardiac hypertrophy in H9c2 cells was supported by the ability of resveratrol, an AhR antagonist, to block the SUN-induced hypertrophy and the ability of SB203580, a novel AhR agonist, to potentiate SUN-induced hypertrophic genes. This is the first demonstration that SUN induces hypertrophic genes in vivo and in vitro rat cardiomyocyte through AhR/CYP1A1-mediated mechanism.
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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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AhR signalling and dioxin toxicity. Toxicol Lett 2013; 230:225-33. [PMID: 24239782 DOI: 10.1016/j.toxlet.2013.10.039] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 10/14/2013] [Accepted: 10/18/2013] [Indexed: 12/02/2022]
Abstract
Dioxins are a family of molecules associated to several industrial accidents such as Ludwigshafen in 1953 or Seveso in 1976, to the Agent Orange used during the war of Vietnam, and more recently to the poisoning of the former president of Ukraine, Victor Yushchenko. These persistent organic pollutants are by-products of industrial activity and bind to an intracellular receptor, AhR, with a high potency. In humans, exposure to dioxins, in particular 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induces a cutaneous syndrome known as chloracne, consisting in the development of many small skin lesions (hamartoma), lasting for 2-5 years. Although TCDD has been classified by the WHO as a human carcinogen, its carcinogenic potential to humans is not clearly demonstrated. It was first believed that AhR activation accounted for most, if not all, biological properties of dioxins. However, certain AhR agonists found in vegetables do not induce chloracne, and other chemicals, in particular certain therapeutic agents, may induce a chloracne-like syndrome without activating AhR. It is time to rethink the mechanism of dioxin toxicity and analyse in more details the biological events following exposure to these compounds and other AhR agonists, some of which have a very different chemical structure than TCDD. In particular various food-containing AhR agonists are non-toxic and may on the contrary have beneficial properties to human health.
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Abstract
Cytochrome P450 enzymes (CYPs) metabolize many drugs that act on the central nervous system (CNS), such as antidepressants and antipsychotics; drugs of abuse; endogenous neurochemicals, such as serotonin and dopamine; neurotoxins; and carcinogens. This takes place primarily in the liver, but metabolism can also occur in extrahepatic organs, including the brain. This is important for CNS-acting drugs, as variation in brain CYP-mediated metabolism may be a contributing factor when plasma levels do not predict drug response. This review summarizes the characterization of CYPs in the brain, using examples from the CYP2 subfamily, and discusses sources of variation in brain CYP levels and metabolism. Some recent experiments are described that demonstrate how changes in brain CYP metabolism can influence drug response, toxicity and drug-induced behaviours. Advancing knowledge of brain CYP-mediated metabolism may help us understand why patients respond differently to drugs used in psychiatry and predict risk for psychiatric disorders, including neurodegenerative diseases and substance abuse.
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Affiliation(s)
| | - Rachel F. Tyndale
- Correspondence to: R.F. Tyndale, Department of Pharmacology and Toxicology, 1 King’s College Circle, Toronto ON M5S 1A8;
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Matsubara T, Tanaka N, Krausz KW, Manna SK, Kang DW, Anderson ER, Luecke H, Patterson AD, Shah YM, Gonzalez FJ. Metabolomics identifies an inflammatory cascade involved in dioxin- and diet-induced steatohepatitis. Cell Metab 2012; 16:634-44. [PMID: 23140643 PMCID: PMC3496181 DOI: 10.1016/j.cmet.2012.10.006] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 09/17/2012] [Accepted: 10/18/2012] [Indexed: 12/13/2022]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is among the most potent environmentally toxic compounds. Serum metabolomics identified azelaic acid monoesters as significantly increased metabolites after TCDD treatment, due to downregulation of hepatic carboxylesterase 3 (CES3, also known as triglyceride hydrolase) expression in an arylhydrocarbon receptor (AhR)-dependent manner in mice. The decreased CES3 expression was accomplished by TCDD-stimulated TGFβ-SMAD3 and IL6-STAT3 signaling, but not by direct AhR signaling. Methionine- and choline-deficient (MCD) diet-treated mice also showed enhanced serum azelaic acid monoester levels after attenuation of hepatic CES3 expression, while db/db mice did not, thus suggesting an association with steatohepatitis. Forced expression of CES3 reversed serum azelaic acid monoester/azelaic acid ratios and hepatic TGFβ mRNA levels in TCDD- and MCD diet-treated mice and ameliorated steatohepatitis induced by MCD diet. These results support the view that azelaic acid monoesters are possible indicators of TCDD exposure and steatohepatitis and suggest a link between CES3, TGFβ, and steatohepatitis.
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Affiliation(s)
- Tsutomu Matsubara
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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Chavan H, Krishnamurthy P. Polycyclic aromatic hydrocarbons (PAHs) mediate transcriptional activation of the ATP binding cassette transporter ABCB6 gene via the aryl hydrocarbon receptor (AhR). J Biol Chem 2012; 287:32054-68. [PMID: 22761424 DOI: 10.1074/jbc.m112.371476] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Liver is endowed with a mechanism to induce hepatic cytochromes P450 (CYP450s) in response to therapeutic drugs and environmental contaminants, leading to increased detoxification and elimination of the xenobiotics. Each CYP450 is composed of an apoprotein moiety and a heme prosthetic group, which is required for CYP450 activity. Thus, under conditions of CYP450 induction, there is a coordinate increase in heme biosynthesis to compensate for the increased expression of CYP450s. ABCB6, a mitochondrial ATP binding cassette transporter, which regulates coproporphyrinogen transport from the cytoplasm into the mitochondria to complete heme biosynthesis, represents a previously unrecognized rate-limiting step in heme biosynthesis. However, it is not known if exposure to drugs and environmental contaminants induces ABCB6 expression, to assure an adequate and apparently coordinated supply of heme for the generation of functional cytochrome holoprotein. In the present study, we demonstrate that polycyclic aromatic hydrocarbons (PAHs), the widely distributed environmental toxicants shown to induce porphyrin accumulation causing hepatic porphyria, up-regulate ABCB6 expression in both mice and humans. Using siRNA technology and Abcb6 knock-out mice, we demonstrate that PAH-mediated increase in hepatic porphyrins is compromised in the absence of ABCB6. Moreover, in vivo studies in aryl hydrocarbon receptor (AhR) knock-out mice demonstrate that PAH induction of ABCB6 is mediated by AhR. Promoter activation studies combined with electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrate direct interactions between the AhR binding sites in the ABCB6 promoter and the AhR receptor, implicating drug activation mechanisms for ABCB6 similar to those found in inducible cytochrome P450s. These studies are the first to describe direct transcriptional activation of both mouse and human ABCB6 by xenobiotics.
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Affiliation(s)
- Hemantkumar Chavan
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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Rysavy NM, Maaetoft-Udsen K, Turner H. Dioxins: diagnostic and prognostic challenges arising from complex mechanisms. J Appl Toxicol 2012; 33:1-8. [PMID: 22610997 DOI: 10.1002/jat.2759] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 02/27/2012] [Accepted: 02/28/2012] [Indexed: 12/23/2022]
Abstract
Dioxins are ubiquitous environmental challenges to humans, with a pervasiveness that arises from 200 years of rapid industrialization and mechanization of Western societies and which is now extending into the developing world. In spite of their penetrance of the human biota, these compounds are poorly understood in terms of their true physiological potential for harm, and the mechanisms by which they impact cellular and organ level function are only recently becoming clear. Emerging awareness that chronic exposures to toxins may have generational and subtle effects on the outcomes of diseases such as cancer and diabetes, which are already multifactorial and highly complex, creates the context for the current review paper. Here, we summarize dioxin exposure paradigms and the resulting physiological effects that have been documented in animals and humans. Novel insights into potential endogenous end exogenous ligands, as well as the mechanisms by which these ligands impact acute and chronic cellular processes, are discussed. We develop the idea that the diagnosis of dioxin exposure, the subtleties of the cellular effects of the compounds and prognosis of the long-term effects of exposure are problems requiring that researchers leverage the power of genomics and epigenetics. However, the continuation of longitudinal epidemiological studies and the development of a firmer basis from which to extrapolate animal studies will be critical in ensuring optimal insight from these resource-intensive techniques.
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Affiliation(s)
- Noel M Rysavy
- Laboratory of Immunology and Signal Transduction, Chaminade University, Honolulu, HI 96822, USA
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Malek G, Dwyer M, McDonnell D. Exploring the potential role of the oxidant-activated transcription factor aryl hydrocarbon receptor in the pathogenesis of AMD. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 723:51-9. [PMID: 22183315 DOI: 10.1007/978-1-4614-0631-0_8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Goldis Malek
- Department of Ophthalmology, Duke University, Durham, NC 27701, USA.
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2,3,7,8-Tetrachlorodibenzo-p-dioxin treatment alters eicosanoid levels in several organs of the mouse in an aryl hydrocarbon receptor-dependent fashion. Toxicol Appl Pharmacol 2011; 259:143-51. [PMID: 22230337 DOI: 10.1016/j.taap.2011.12.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 11/22/2011] [Accepted: 12/05/2011] [Indexed: 10/14/2022]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) adversely affects many mammalian organs and tissues. These effects are mediated by the aryl hydrocarbon receptor (AHR). CYP1A1, CYP1A2 and CYP1B1 are upregulated by the liganded AHR. These (and other) cytochromes P450 can metabolize arachidonic acid into a variety of bioactive eicosanoids. Towards investigating a potential role of eicosanoids in TCDD toxicity, arachidonic acid, two other unsaturated long-chain fatty acids, and up to twenty-five eicosanoids were measured in five organs/tissues of male and female wild-type and Ahr null mice treated or untreated with TCDD. TCDD generally increased the levels of the four dihydroxyeicosatrienoic acids (DHETs) and (where measured) 5,6-epoxyeicosatrienoic acid and 18-, 19- and 20-hydroxyeicosatrienoic acids (HETEs) in the serum, liver, spleen and lungs, but not the heart, of both sexes, and increased the levels in the serum, liver and spleen of several metabolites that are usually considered products of lipoxygenase activity, but which may also be generated by cytochromes P450. TCDD also increased the levels of the esterified forms of these eicosanoids in the liver in parallel with the corresponding free forms. The levels of prostanoids were generally not affected by TCDD. The above changes did not occur in Ahr null mice, and are therefore mediated by the AHR. TCDD increased the mRNA levels of Cyp1a1, Cyp1a2, Cyp1b1 and the Pla2g12a form of phospholipase A(2) to varying degrees in the different organs, and these increases correlated with some but not all the changes in eicosanoids levels in the organs, suggesting that other enzymes may also be involved.
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Saurat JH, Kaya G, Saxer-Sekulic N, Pardo B, Becker M, Fontao L, Mottu F, Carraux P, Pham XC, Barde C, Fontao F, Zennegg M, Schmid P, Schaad O, Descombes P, Sorg O. The cutaneous lesions of dioxin exposure: lessons from the poisoning of Victor Yushchenko. Toxicol Sci 2011; 125:310-7. [PMID: 21998131 DOI: 10.1093/toxsci/kfr223] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Several million people are exposed to dioxin and dioxin-like compounds, primarily through food consumption. Skin lesions historically called "chloracne" are the most specific sign of abnormal dioxin exposure and classically used as a key marker in humans. We followed for 5 years a man who had been exposed to the most toxic dioxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), at a single oral dose of 5 million-fold more than the accepted daily exposure in the general population. We adopted a molecular medicine approach, aimed at identifying appropriate therapy. Skin lesions, which progressively covered up to 40% of the body surface, were found to be hamartomas, which developed parallel to a complete and sustained involution of sebaceous glands, with concurrent transcriptomic alterations pointing to the inhibition of lipid metabolism and the involvement of bone morphogenetic proteins signaling. Hamartomas created a new compartment that concentrated TCDD up to 10-fold compared with serum and strongly expressed the TCDD-metabolizing enzyme cytochrome P450 1A1, thus representing a potentially significant source of enzymatic activity, which may add to the xenobiotic metabolism potential of the classical organs such as the liver. This historical case provides a unique set of data on the human tissue response to dioxin for the identification of new markers of exposure in human populations. The herein discovered adaptive cutaneous response to TCDD also points to the potential role of the skin in the metabolism of food xenobiotics.
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Affiliation(s)
- Jean-Hilaire Saurat
- Swiss Centre for Applied Human Toxicology, Dermatotoxicology Unit, University of Geneva, 1211 Geneva 4, Switzerland.
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Ferguson CS, Tyndale RF. Cytochrome P450 enzymes in the brain: emerging evidence of biological significance. Trends Pharmacol Sci 2011; 32:708-14. [PMID: 21975165 DOI: 10.1016/j.tips.2011.08.005] [Citation(s) in RCA: 169] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 08/25/2011] [Accepted: 08/29/2011] [Indexed: 10/17/2022]
Abstract
Cytochrome P450 (CYP) enzymes are responsible for the metabolism of many exogenous and endogenous compounds. CYPs are abundant in the liver and are also expressed in many extra-hepatic tissues including the brain. Although total CYP levels in the brain are much lower than in the liver, brain CYPs are concentrated near drug targets in specific regions and cell types, and can potentially have a considerable impact on local metabolism. Individual differences in brain CYP metabolism, due to inducers, inhibitors or genetic variation, can influence sensitivity and response to centrally acting drugs. Brain CYPs may also play a role in modulating brain activity, behavior, susceptibility to central nervous system diseases and treatment outcomes. This review highlights recent progress that has been made in understanding the functional significance of CYPs in the brain.
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Affiliation(s)
- Charmaine S Ferguson
- Centre for Addiction and Mental Health and Departments of Psychiatry, Pharmacology and Toxicology, University of Toronto, 1 King's College Circle, Toronto, ON, Canada
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Parman T, Bunin DI, Ng HH, McDunn JE, Wulff JE, Wang A, Swezey R, Rasay L, Fairchild DG, Kapetanovic IM, Green CE. Toxicogenomics and metabolomics of pentamethylchromanol (PMCol)-induced hepatotoxicity. Toxicol Sci 2011; 124:487-501. [PMID: 21920950 DOI: 10.1093/toxsci/kfr238] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Pentamethyl-6-chromanol (PMCol), a chromanol-type compound related to vitamin E, was proposed as an anticancer agent with activity against androgen-dependent cancers. In repeat dose-toxicity studies in rats and dogs, PMCol caused hepatotoxicity, nephrotoxicity, and hematological effects. The objectives of this study were to determine the mechanisms of the observed toxicity and identify sensitive early markers of target organ injury by integrating classical toxicology, toxicogenomics, and metabolomic approaches. PMCol was administered orally to male Sprague-Dawley rats at 200 and 2000 mg/kg daily for 7 or 28 days. Changes in clinical chemistry included elevated alanine aminotransferase, total bilirubin, cholesterol and triglycerides-indicative of liver toxicity that was confirmed by microscopic findings (periportal hepatocellular hydropic degeneration and cytomegaly) in treated rats. Metabolomic evaluations of liver revealed time- and dose-dependent changes, including depletion of total glutathione and glutathione conjugates, decreased methionine, and increased S-adenosylhomocysteine, cysteine, and cystine. PMCol treatment also decreased cofactor levels, namely, FAD and increased NAD(P)+. Microarray analysis of liver found that differentially expressed genes were enriched in the glutathione and cytochrome P450 pathways by PMCol treatment. Reverse transcription-polymerase chain reaction of six upregulated genes and one downregulated gene confirmed the microarray results. In conclusion, the use of metabolomics and toxicogenomics demonstrates that chronic exposure to high doses of PMCol induces liver damage and dysfunction, probably due to both direct inhibition of glutathione synthesis and modification of drug metabolism pathways. Depletion of glutathione due to PMCol exposure ultimately results in a maladaptive response, increasing the consumption of hepatic dietary antioxidants and resulting in elevated reactive oxygen species levels associated with hepatocellular damage and deficits in liver function.
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Affiliation(s)
- Toufan Parman
- Biosciences Division, SRI International, Menlo Park, California 94025-3493, USA.
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Structural features of cytochrome P450 1A associated with the absence of EROD activity in liver of the loricariid catfish Pterygoplichthys sp. Gene 2011; 489:111-8. [PMID: 21840383 DOI: 10.1016/j.gene.2011.07.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 06/19/2011] [Accepted: 07/10/2011] [Indexed: 11/20/2022]
Abstract
The Amazon catfish genus Pterygoplichthys (Loricariidae, Siluriformes) is closely related to the loricariid genus Hypostomus, in which at least two species lack detectable ethoxyresorufin-O-deethylase (EROD) activity, typically catalyzed by cytochrome P450 1 (CYP1) enzymes. Pterygoplichthys sp. liver microsomes also lacked EROD, as well as activity with other substituted resorufins, but aryl hydrocarbon receptor agonists induced hepatic CYP1A mRNA and protein suggesting structural/functional differences in Pterygoplichthys CYP1s from those in other vertebrates. Comparing the sequences of CYP1As of Pterygoplichthys sp. and of two phylogenetically related siluriform species that do catalyze EROD (Ancistrus sp., Loricariidae and Corydoras sp., Callichthyidae) showed that these three proteins share amino acids at 17 positions that are not shared by any fish in a set of 24 other species. Pterygoplichthys and Ancistrus (the loricariids) have an additional 22 amino acid substitutions in common that are not shared by Corydoras or by other fish species. Pterygoplichthys has six exclusive amino acid substitutions. Molecular docking and dynamics simulations indicate that Pterygoplichthys CYP1A has a weak affinity for ER, which binds infrequently in a productive orientation, and in a less stable conformation than in CYP1As of species that catalyze EROD. ER also binds with the carbonyl moiety proximal to the heme iron. Pterygoplichthys CYP1A has amino acid substitutions that reduce the frequency of correctly oriented ER in the AS preventing the detection of EROD activity. The results indicate that loricariid CYP1As may have a peculiar substrate selectivity that differs from CYP1As of most vertebrate.
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Diani-Moore S, Ram P, Li X, Mondal P, Youn DY, Sauve AA, Rifkind AB. Identification of the aryl hydrocarbon receptor target gene TiPARP as a mediator of suppression of hepatic gluconeogenesis by 2,3,7,8-tetrachlorodibenzo-p-dioxin and of nicotinamide as a corrective agent for this effect. J Biol Chem 2010; 285:38801-10. [PMID: 20876576 DOI: 10.1074/jbc.m110.131573] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The environmental toxin TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin, dioxin) produces diverse toxic effects including a lethal wasting syndrome whose hallmark is suppressed hepatic gluconeogenesis. All TCDD toxicities require activation of the aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor. Whereas the mechanism for AHR induction of target genes is well understood, it is not known how AHR activation produces any TCDD toxicity. This report identifies for the first time an AHR target gene, TiPARP (TCDD-inducible poly(ADP-ribose) polymerase, PARP7) that can mediate a TCDD toxicity, i.e. suppression of hepatic gluconeogenesis. TCDD suppressed hepatic glucose production, expression of key gluconeogenic genes, phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphatase (G6Pase), and NAD(+) levels, and increased PARP activity and TiPARP expression. TCDD also increased acetylation and ubiquitin-dependent proteosomal degradation of the peroxisome proliferator-activated receptor γ coactivator 1 α (PGC1α), a coactivator of PEPCK and G6Pase transcription. TiPARP overexpression reproduced TCDD effects on glucose output and NAD(+) levels whereas TiPARP silencing diminished them. TiPARP overexpression also increased PGC1α acetylation and decreased PGC1α levels. In contrast, silencing of cytochromes P450 (CYP) 1A, main AHR-induced genes, did not alter TCDD suppression of gluconeogenesis. The vitamin B3 constituent, nicotinamide (NAM), prevented TCDD suppression of glucose output, NAD(+), and gluconeogenic genes and stabilized PGC1α. The corrective effects of NAM could be attributed to increased NAD(+) levels and suppression of AHR target gene induction. The results reveal that TiPARP can mediate a TCDD effect, that the AHR is linked to PGC1α function and stability and that NAM has novel AHR antagonist activity.
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Affiliation(s)
- Silvia Diani-Moore
- Department of Pharmacology, Weill Medical College of Cornell University, New York, New York 10065, USA
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