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Liang S, Bo H, Zhang Y, Zhen H, Zhong L. Alizarin, an Agonist of AHR Receptor, Enhances CYP1A1 Enzyme Activity and Induces Transcriptional Changes in Hepatoma Cells. Molecules 2023; 28:7373. [PMID: 37959792 PMCID: PMC10650112 DOI: 10.3390/molecules28217373] [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: 09/24/2023] [Revised: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 11/15/2023] Open
Abstract
The phytopigment alizarin was previously characterized as an anti-tumor drug owing to its antioxidant or antigenotoxic activities. However, the safety of alizarin is currently still under dispute. In this study, we explored the activity of alizarin in the AHR-CYP1A1 pathway and analyzed the transcriptional changes affected by alizarin using human hepatoma cell line HepG2-based assays. The results showed that alizarin decreased HepG2 cell viability in a dose-dependent manner, with IC50 values between 160.4 and 216.8 μM. Furthermore, alizarin significantly upregulated the expression of CYP1A1 and increased the ethoxyresorufin-O-deethylase activity. Alizarin also exhibited agonistic activity toward the AHR receptor in the XRE-mediated luciferase reporter gene assay, which was further confirmed via the molecular docking assay. In addition, the transcriptional analysis indicated that alizarin may act as a potential carcinogen through significantly enriching several items related to cancer in both DO and KEGG analysis. In brief, our findings indicated that alizarin shows agonistic activities to the AHR receptor through activating the AHR-CYP1A1 signaling pathway in HepG2 cells, which may lead to the risks for cancer developing.
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Affiliation(s)
- Shengxian Liang
- Institute of Life Sciences and Green Development, College of Life Sciences, Hebei University, Baoding 071000, China; (H.B.); (Y.Z.); (H.Z.)
| | - Haimei Bo
- Institute of Life Sciences and Green Development, College of Life Sciences, Hebei University, Baoding 071000, China; (H.B.); (Y.Z.); (H.Z.)
| | - Yue Zhang
- Institute of Life Sciences and Green Development, College of Life Sciences, Hebei University, Baoding 071000, China; (H.B.); (Y.Z.); (H.Z.)
| | - Hongcheng Zhen
- Institute of Life Sciences and Green Development, College of Life Sciences, Hebei University, Baoding 071000, China; (H.B.); (Y.Z.); (H.Z.)
| | - Li Zhong
- Institute of Life Sciences and Green Development, College of Life Sciences, Hebei University, Baoding 071000, China; (H.B.); (Y.Z.); (H.Z.)
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, Pomona, CA 91766, USA
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Pinto CJG, Ávila-Gálvez MÁ, Lian Y, Moura-Alves P, Nunes Dos Santos C. Targeting the aryl hydrocarbon receptor by gut phenolic metabolites: A strategy towards gut inflammation. Redox Biol 2023; 61:102622. [PMID: 36812782 PMCID: PMC9958510 DOI: 10.1016/j.redox.2023.102622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Revised: 01/25/2023] [Accepted: 01/30/2023] [Indexed: 02/04/2023] Open
Abstract
The Aryl Hydrocarbon Receptor (AHR) is a ligand-dependent transcription factor able to control complex transcriptional processes in several cell types, which has been correlated with various diseases, including inflammatory bowel diseases (IBD). Numerous studies have described different compounds as ligands of this receptor, like xenobiotics, natural compounds, and several host-derived metabolites. Dietary (poly)phenols have been studied regarding their pleiotropic activities (e.g., neuroprotective and anti-inflammatory), but their AHR modulatory capabilities have also been considered. However, dietary (poly)phenols are submitted to extensive metabolism in the gut (e.g., gut microbiota). Thus, the resulting gut phenolic metabolites could be key players modulating AHR since they are the ones that reach the cells and may exert effects on the AHR throughout the gut and other organs. This review aims at a comprehensive search for the most abundant gut phenolic metabolites detected and quantified in humans to understand how many have been described as AHR modulators and what could be their impact on inflammatory gut processes. Even though several phenolic compounds have been studied regarding their anti-inflammatory capacities, only 1 gut phenolic metabolite, described as AHR modulator, has been evaluated on intestinal inflammatory models. Searching for AHR ligands could be a novel strategy against IBD.
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Affiliation(s)
- Catarina J G Pinto
- iNOVA4Health, NOVA Medical School
- Faculdade de Ciências Médicas, NMS
- FCM, Universidade Nova de Lisboa, Lisboa, Portugal; IBMC, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal; I3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal
| | - María Ángeles Ávila-Gálvez
- iNOVA4Health, NOVA Medical School
- Faculdade de Ciências Médicas, NMS
- FCM, Universidade Nova de Lisboa, Lisboa, Portugal; iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, Oeiras, Portugal
| | - Yilong Lian
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, OX3 7DQ, Oxford, United Kingdom
| | - Pedro Moura-Alves
- IBMC, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal; I3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal; Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, OX3 7DQ, Oxford, United Kingdom.
| | - Cláudia Nunes Dos Santos
- iNOVA4Health, NOVA Medical School
- Faculdade de Ciências Médicas, NMS
- FCM, Universidade Nova de Lisboa, Lisboa, Portugal; iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, Oeiras, Portugal.
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An overview of aryl hydrocarbon receptor ligands in the Last two decades (2002–2022): A medicinal chemistry perspective. Eur J Med Chem 2022; 244:114845. [DOI: 10.1016/j.ejmech.2022.114845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 09/28/2022] [Accepted: 10/08/2022] [Indexed: 11/21/2022]
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Grishanova AY, Perepechaeva ML. Aryl Hydrocarbon Receptor in Oxidative Stress as a Double Agent and Its Biological and Therapeutic Significance. Int J Mol Sci 2022; 23:ijms23126719. [PMID: 35743162 PMCID: PMC9224361 DOI: 10.3390/ijms23126719] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/14/2022] [Accepted: 06/14/2022] [Indexed: 12/02/2022] Open
Abstract
The aryl hydrocarbon receptor (AhR) has long been implicated in the induction of a battery of genes involved in the metabolism of xenobiotics and endogenous compounds. AhR is a ligand-activated transcription factor necessary for the launch of transcriptional responses important in health and disease. In past decades, evidence has accumulated that AhR is associated with the cellular response to oxidative stress, and this property of AhR must be taken into account during investigations into a mechanism of action of xenobiotics that is able to activate AhR or that is susceptible to metabolic activation by enzymes encoded by the genes that are under the control of AhR. In this review, we examine various mechanisms by which AhR takes part in the oxidative-stress response, including antioxidant and prooxidant enzymes and cytochrome P450. We also show that AhR, as a participant in the redox balance and as a modulator of redox signals, is being increasingly studied as a target for a new class of therapeutic compounds and as an explanation for the pathogenesis of some disorders.
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5
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Nobile V, Schiano I, Peral A, Giardina S, Spartà E, Caturla N. Antioxidant and reduced skin-ageing effects of a polyphenol-enriched dietary supplement in response to air pollution: a randomized, double-blind, placebo-controlled study. Food Nutr Res 2021; 65:5619. [PMID: 33889065 PMCID: PMC8035891 DOI: 10.29219/fnr.v65.5619] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 02/23/2021] [Accepted: 02/26/2021] [Indexed: 12/24/2022] Open
Abstract
Background Air pollution exposure is one of the major threats to skin health and accelerates skin ageing mainly through oxidative stress mechanisms. Since it is difficult to minimize skin exposure to air pollutants, especially in urban areas, strategies to protect the skin are needed. Plant phenolic compounds have been found to be effective in attenuating cellular oxidative stress and inflammation induced by different air pollutants and a dietary approach based on these compounds could provide an efficient protection measure. Objective Here we investigated the efficacy of a commercially available polyphenol-enriched dietary supplement (Zeropollution®) in reducing pollution-induced oxidative stress and in improving different skin parameters related to skin ageing of Caucasian and Asian subjects exposed to air pollution. Zeropollution is composed of four standardized herbal extracts: Olea europaea leaf, Lippia citriodora, Rosmarinus officinalis, and Sophora japonica. Design A double-blind randomized, parallel group study was carried out on 100 outdoor workers living in a polluted urban European area (Milan) to assess the efficacy of the dietary supplement. The total antioxidant capacity on saliva (FRAP), the oxidative damage on skin (lipoperoxides content), skin moisturization (corneometer), transepidermal water loss (tewameter), skin radiance and colour (spectrophotometer), skin elasticity (cutometer), skin sebum content (sebumeter), and the skin roughness (image analysis) were measured. Results Both inter-group and intra-group analysis proved that the dietary supplement improved all clinical and biochemical-monitored parameters, in both Caucasian and Asian individuals. Some of the positive effects such as decreased wrinkle depth, increased elasticity and firmness, improved skin moisturization and transepidermal water loss, and reduced dark spots pigmentation were statistically significant as early as 2 weeks of product consumption. Conclusions The results of the study indicate reduced oxidative stress-induced skin damage in both Asian and Caucasian women living in a polluted urban area. Therefore, the oral intake of this four-plant based supplement could be considered a complementary nutrition strategy to avoid the negative effects of environmental pollution exposure.
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Affiliation(s)
| | | | - Ana Peral
- Complife Italia Srl, San Martino Siccomario, Pavia, Italy
| | | | | | - Nuria Caturla
- Complife Italia Srl, San Martino Siccomario, Pavia, Italy
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Brinkmann V, Schiavi A, Shaik A, Puchta DR, Ventura N. Dietary and environmental factors have opposite AhR-dependent effects on C. elegans healthspan. Aging (Albany NY) 2020; 13:104-133. [PMID: 33349622 PMCID: PMC7835051 DOI: 10.18632/aging.202316] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 11/08/2020] [Indexed: 12/14/2022]
Abstract
Genetic, dietary, and environmental factors concurrently shape the aging process. The aryl hydrocarbon receptor (AhR) was discovered as a dioxin-binding transcription factor involved in the metabolism of different environmental toxicants in vertebrates. Since then, the variety of pathophysiological processes regulated by the AhR has grown, ranging from immune response, metabolic pathways, and aging. Many modulators of AhR activity may impact on aging and age-associated pathologies, but, whether their effects are AhR-dependent has never been explored. Here, using Caenorhabditis elegans, as an elective model organism for aging studies, we show for the first time that lack of CeAHR-1 can have opposite effects on health and lifespan in a context-dependent manner. Using known mammalian AhR modulators we found that, ahr-1 protects against environmental insults (benzo(a)pyrene and UVB light) and identified a new role for AhR-bacterial diet interaction in animal lifespan, stress resistance, and age-associated pathologies. We narrowed down the dietary factor to a bacterially extruded metabolite likely involved in tryptophan metabolism. This is the first study clearly establishing C. elegans as a good model organism to investigate evolutionarily conserved functions of AhR-modulators and -regulated processes, indicating it can be exploited to contribute to the discovery of novel information about AhR in mammals.
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Affiliation(s)
- Vanessa Brinkmann
- Leibniz Institute for Environmental Medicine, Auf’m Hennekamp 50, 40225 Düsseldorf, Germany
| | - Alfonso Schiavi
- Leibniz Institute for Environmental Medicine, Auf’m Hennekamp 50, 40225 Düsseldorf, Germany.,Institute of Clinical Chemistry and Laboratory Diagnostic, Heinrich Heine University Düsseldorf, Moorenstr 5, 40225 Düsseldorf, Germany
| | - Anjumara Shaik
- Leibniz Institute for Environmental Medicine, Auf’m Hennekamp 50, 40225 Düsseldorf, Germany.,Institute of Clinical Chemistry and Laboratory Diagnostic, Heinrich Heine University Düsseldorf, Moorenstr 5, 40225 Düsseldorf, Germany
| | - Daniel Rüdiger Puchta
- Leibniz Institute for Environmental Medicine, Auf’m Hennekamp 50, 40225 Düsseldorf, Germany
| | - Natascia Ventura
- Leibniz Institute for Environmental Medicine, Auf’m Hennekamp 50, 40225 Düsseldorf, Germany.,Institute of Clinical Chemistry and Laboratory Diagnostic, Heinrich Heine University Düsseldorf, Moorenstr 5, 40225 Düsseldorf, Germany
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7
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The Aryl Hydrocarbon Receptor in Asthma: Friend or Foe? Int J Mol Sci 2020; 21:ijms21228797. [PMID: 33233810 PMCID: PMC7699852 DOI: 10.3390/ijms21228797] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 11/18/2020] [Indexed: 12/14/2022] Open
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that has emerged as an important player in asthma control. AhR is responsive to environmental molecules and endogenous or dietary metabolites and regulates innate and adaptive immune responses. Binding of this receptor by different ligands has led to seemingly opposite responses in different asthma models. In this review, we present two sides of the same coin, with the beneficial and deleterious roles of AhR evaluated using known endogenous or exogenous ligands, deficient mice or antagonists. On one hand, AhR has an anti-inflammatory role since its activation in dendritic cells blocks the generation of pro-inflammatory T cells or shifts macrophages toward an anti-inflammatory M2 phenotype. On the other hand, AhR activation by particle-associated polycyclic aromatic hydrocarbons from the environment is pro-inflammatory, inducing mucus hypersecretion, airway remodelling, dysregulation of antigen presenting cells and exacerbates asthma features. Data concerning the role of AhR in cells from asthmatic patients are also reviewed, since AhR could represent a potential target for therapeutic immunomodulation.
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8
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Brinkmann V, Ale-Agha N, Haendeler J, Ventura N. The Aryl Hydrocarbon Receptor (AhR) in the Aging Process: Another Puzzling Role for This Highly Conserved Transcription Factor. Front Physiol 2020; 10:1561. [PMID: 32009975 PMCID: PMC6971224 DOI: 10.3389/fphys.2019.01561] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 12/11/2019] [Indexed: 12/26/2022] Open
Abstract
Aging is the most important risk factor for the development of major life-threatening diseases such as cardiovascular disorders, cancer, and neurodegenerative disorders. The aging process is characterized by the accumulation of damage to intracellular macromolecules and it is concurrently shaped by genetic, environmental and nutritional factors. These factors influence the functionality of mitochondria, which play a central role in the aging process. Mitochondrial dysfunction is one of the hallmarks of aging and is associated with increased fluxes of ROS leading to damage of mitochondrial components, impaired metabolism of fatty acids, dysregulated glucose metabolism, and damage of adjacent organelles. Interestingly, many of the environmental (e.g., pollutants and other toxicants) and nutritional (e.g., flavonoids, carotenoids) factors influencing aging and mitochondrial function also directly or indirectly affect the activity of a highly conserved transcription factor, the Aryl hydrocarbon Receptor (AhR). Therefore, it is not surprising that many studies have already indicated a role of this versatile transcription factor in the aging process. We also recently found that the AhR promotes aging phenotypes across species. In this manuscript, we systematically review the existing literature on the contradictory studies indicating either pro- or anti-aging effects of the AhR and try to reconcile the seemingly conflicting data considering a possible dependency on the animal model, tissue, as well as level of AhR expression and activation. Moreover, given the crucial role of mitochondria in the aging process, we summarize the growing body of evidence pointing toward the influence of AhR on mitochondria, which can be of potential relevance for aging.
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Affiliation(s)
- Vanessa Brinkmann
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
| | - Niloofar Ale-Agha
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
| | - Judith Haendeler
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.,Institute of Clinical Chemistry and Laboratory Diagnostic, Medical Faculty, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
| | - Natascia Ventura
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.,Institute of Clinical Chemistry and Laboratory Diagnostic, Medical Faculty, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
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Modulation of benzo[a]pyrene-DNA adduct formation by CYP1 inducer and inhibitor. Genes Environ 2017; 39:14. [PMID: 28405246 PMCID: PMC5385587 DOI: 10.1186/s41021-017-0076-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 02/15/2017] [Indexed: 02/05/2023] Open
Abstract
Benzo[a]pyrene (BaP) is a well-studied pro-carcinogen that is metabolically activated by cytochrome P450 enzymes. Cytochrome P4501A1 (CYP1A1) has been considered to play a central role in the activation step, which is essential for the formation of DNA adducts. This enzyme is strongly induced by many different chemical agents, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), which binds to the aryl hydrocarbon receptor (AhR). Therefore, AhR activators are suspected to have the potential to aggravate the toxicity of BaP through the induction of CYP1A1. Besides, CYP1A1 inhibitors, including its substrates, are estimated to have preventive effects against BaP toxicity. However, strangely, increased hepatic BaP–DNA adduct levels have been reported in Cyp1a1 knockout mice. Moreover, numerous reports describe that concomitant treatment of AhR activators reduced BaP–DNA adduct formation. In an experiment using several human cell lines, TCDD had diverse modulatory effects on BaP–DNA adducts, both enhancing and inhibiting their formation. In this review, we focus on the factors that could influence the BaP–DNA adduct formation. To interpret these complicated outcomes, we propose a hypothesis that CYP1A1 is a key enzyme for both generation and reduction of (±)-anti-benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE), the major carcinogenic intermediate of BaP. Conversely, CYP1B1 is thought to contribute only to the metabolic activation of BaP related to carcinogenesis.
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Furue M, Uchi H, Mitoma C, Hashimoto-Hachiya A, Chiba T, Ito T, Nakahara T, Tsuji G. Antioxidants for Healthy Skin: The Emerging Role of Aryl Hydrocarbon Receptors and Nuclear Factor-Erythroid 2-Related Factor-2. Nutrients 2017; 9:nu9030223. [PMID: 28273792 PMCID: PMC5372886 DOI: 10.3390/nu9030223] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 02/24/2017] [Accepted: 02/28/2017] [Indexed: 12/24/2022] Open
Abstract
Skin is the outermost part of the body and is, thus, inevitably exposed to UV rays and environmental pollutants. Oxidative stress by these hazardous factors accelerates skin aging and induces skin inflammation and carcinogenesis. Aryl hydrocarbon receptors (AHRs) are chemical sensors that are abundantly expressed in epidermal keratinocytes and mediate the production of reactive oxygen species. To neutralize or minimize oxidative stress, the keratinocytes also express nuclear factor-erythroid 2-related factor-2 (NRF2), which is a master switch for antioxidant signaling. Notably, there is fine-tuned crosstalk between AHR and NRF2, which mutually increase or decrease their activation states. Many NRF2-mediated antioxidant phytochemicals are capable of up- and downmodulating AHR signaling. The precise mechanisms by which these phytochemicals differentially affect the AHR and NRF2 system remain largely unknown and warrant future investigation.
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Affiliation(s)
- Masutaka Furue
- Department of Dermatology, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
- Research and Clinical Center for Yusho and Dioxin, Kyushu University, Fukuoka 812-8582, Japan.
- Division of Skin Surface Sensing, Department of Dermatology, Kyushu University, Fukuoka 812-8582, Japan.
| | - Hiroshi Uchi
- Department of Dermatology, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
| | - Chikage Mitoma
- Department of Dermatology, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
- Research and Clinical Center for Yusho and Dioxin, Kyushu University, Fukuoka 812-8582, Japan.
| | - Akiko Hashimoto-Hachiya
- Department of Dermatology, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
| | - Takahito Chiba
- Department of Dermatology, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
| | - Takamichi Ito
- Department of Dermatology, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
| | - Takeshi Nakahara
- Department of Dermatology, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
- Division of Skin Surface Sensing, Department of Dermatology, Kyushu University, Fukuoka 812-8582, Japan.
| | - Gaku Tsuji
- Department of Dermatology, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
- Research and Clinical Center for Yusho and Dioxin, Kyushu University, Fukuoka 812-8582, Japan.
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Harada A, Sugihara K, Watanabe Y, Yamaji S, Kitamura S, Ohta S. [Aryl Hydrocarbon Receptor Ligand Activity of Extracts from 62 Herbal Medicines and Effect on Cytochrome P450 Activity]. YAKUGAKU ZASSHI 2016; 135:1185-96. [PMID: 26423875 DOI: 10.1248/yakushi.15-00153] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Aryl hydrocarbon receptor (AhR) ligand activity of the extracts of 62 herbal medicines was examined using yeast reporter assay. Fifty-eight herbal extracts exhibited AhR ligand activity. The highest activity was observed with Ogon (Scutellariae Radix), followed by Oren (Coptidis Rhizoma), Kujin (Sophorae Radix) and Shoma (Cimicifiigae Rhizoma). When these extracts were treated with hesperinase, a hydrolase for sugar conjugates, the aglycones showed higher activity than the parent extracts. Among the constituents of Ogon extract, baicalein and wogonin showed AhR ligand activity, while the sugar conjugate of baicalein, baicalin, was inactive. Among the flavonoid components of these herbal medicines, flavone and chrysin exhibited high ligand activity for AhR. Ethoxyresorufin O-dealkylase (EROD) activity due to CYP1A1 in HepG2 cells was enhanced by the addition of baicalein. Baicalein also decreased the 3-methylcholanthrene-induced increase of EROD activity, but this effect was not statistically significant. When wogonin or baicalein was orally administered at the dose of 100 mg/kg to mice, EROD activity in liver was only slightly changed. Furthermore, when Ogon extract was co-administered with 3-methylcholanthrene, the EROD and methoxyresorufin O-dealkylase activities were not significantly changed. These results indicate that many herbal extracts have AhR ligand activity, and their inducing effect on CYP1A1/2 can be evaluated in HepG2 cells.
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Affiliation(s)
- Akiko Harada
- Graduate School of Biomedical and Health Sciences, Hiroshima University
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12
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Fukuda I, Nishiumi S, Mukai R, Yoshida KI, Ashida H. Catechins in tea suppress the activity of cytochrome P450 1A1 through the aryl hydrocarbon receptor activation pathway in rat livers. Int J Food Sci Nutr 2015; 66:300-7. [PMID: 25582180 DOI: 10.3109/09637486.2014.992007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) and halogenated aromatic hydrocarbons (HAHs) develop various adverse effects through activation of an aryl hydrocarbon receptor (AhR). The suppressive effects of brewed green tea and black tea on 3-methylcholanthrene (MC)-induced AhR activation and its downstream events were examined in the liver of rats. Ad-libitum drinking of green tea and black tea suppressed MC-induced AhR activation and elevation of ethoxyresorufin O-deethylase activity in the liver, whereas the teas themselves did not induce them. Tea showed a suppressive fashion on the expression of cytochrome P450 1A1 (CYP1A1). Tea suppressed the AhR activation induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) ex vivo. A part of catechins and theaflavins was present in plasma and liver as conjugated and intact forms. The results of this study suggested that active component(s) of tea are incorporated in the liver and suppress the activity of CYP1As through the AhR activation pathway.
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Affiliation(s)
- Itsuko Fukuda
- Research Center for Food Safety and Security, Graduate School of Agricultural Science, Kobe University , Hyogo , Japan and
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Iida M, Bak SM, Murakami Y, Kim EY, Iwata H. Transient suppression of AHR activity in early red seabream embryos does not prevent the disruption of peripheral nerve projection by 2,3,7,8-tetrachlorodibenzo-p-dioxin. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2014; 154:39-47. [PMID: 24858342 DOI: 10.1016/j.aquatox.2014.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 05/01/2014] [Accepted: 05/02/2014] [Indexed: 06/03/2023]
Abstract
The toxicity of dioxins such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is mainly mediated by an aryl hydrocarbon receptor (AHR), which regulates the transcription of multiple target genes including cytochrome P450 1A (CYP1A). Our pervious study identified the presence of TCDD-induced defects of peripheral nerve projection in red seabream (Pagrus major) embryos. However, it remains unclear whether the TCDD-induced peripheral neurotoxicity is mediated by the AHR. To assess the contribution of the red seabream AHR (rsAHR) signaling pathway to the neuronal toxicity, red seabream embryos at 10h post-fertilization (hpf) were treated for 80 min with TCDD (0, 0.3, 5.3, and 37 nM in seawater) alone or in combination with CH223191 (500 nM in seawater), which is an AHR antagonist. A preliminary in vitro reporter gene assay confirmed that TCDD-induced transcriptional activity via rsAHR1 and rsAHR2 was suppressed by CH223191 treatment in a dose-dependent manner. CYP1A mRNA expression in embryos was determined by 2-step real time quantitative-polymerase chain reaction at 24 and 120 hpf and in situ hybridization at 48, 72, 96 and 120 hpf. The morphology of the peripheral nerve system (PNS) was also microscopically observed by fluorescent staining using an anti-acetylated tubulin antibody at 120 hpf. CYP1A mRNA expression was dose-dependently induced by TCDD at all of the examined developing stages. The suppression of TCDD-induced CYP1A expression by CH223191 treatment was observed in embryos at 24 and 48 hpf, while the effect of the rsAHR antagonist disappeared at 96 and 120 hpf. This phenomenon indicated the transient suppression of TCDD-induced rsAHR activation by CH223191 treatment. The immunostaining of peripheral nerves at 120 hpf demonstrated that the projections of the craniofacial nerve were altered in TCDD-treated embryos, and the frequency of TCDD-induced abnormal projections was not prevented by co-treatment with CH223191. These results indicate that the transient suppression of TCDD-induced rsAHR activation during the early developing stages of the red seabream does not influence the abnormal projection of peripheral nerves. In conclusion, transient rsAHR activation in the early stages of development is not involved in the neurotoxicity.
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Affiliation(s)
- Midori Iida
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan
| | - Su-Min Bak
- Department of Life and Nanopharmaceutical Science, Kyung Hee University, Seoul 130-701, Republic of Korea; Department of Biology, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - Yasunori Murakami
- Graduate School of Science and Engineering, Ehime University, Matsuyama 790-8577, Japan
| | - Eun-Young Kim
- Department of Life and Nanopharmaceutical Science, Kyung Hee University, Seoul 130-701, Republic of Korea; Department of Biology, Kyung Hee University, Seoul 130-701, Republic of Korea
| | - Hisato Iwata
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama 790-8577, Japan.
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14
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Powell JB, Ghotbaddini M. Cancer-promoting and Inhibiting Effects of Dietary Compounds: Role of the Aryl Hydrocarbon Receptor (AhR). ACTA ACUST UNITED AC 2014; 3. [PMID: 25258701 PMCID: PMC4172379 DOI: 10.4172/2167-0501.1000131] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Polyaromatic hydrocarbons, heterocyclic aromatic amines and dioxin-like compounds are environmental carcinogens shown to initiate cancer in a number of tissue types including prostate and breast. These environmental carcinogens elicit their effects through interacting with the aryl hydrocarbon receptor (AhR), a ligand activated transcription factor. Naturally occurring compounds found in fruits and vegetables shown to have anti-carcinogenic effects also interact with the AhR. This review explores dietary and environmental exposure to chemical carcinogens and beneficial natural compounds whose effects are elicited by the AhR.
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Affiliation(s)
- Joann B Powell
- Center for Cancer Research and Therapeutic Development, Clark Atlanta University, Atlanta, GA USA
| | - Maryam Ghotbaddini
- Center for Cancer Research and Therapeutic Development, Clark Atlanta University, Atlanta, GA USA
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15
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Młynarczuk J, Wróbel MH, Kotwica J. Adverse influence of coumestrol on secretory function of bovine luteal cells in the first trimester of pregnancy. ENVIRONMENTAL TOXICOLOGY 2013; 28:411-418. [PMID: 21656645 DOI: 10.1002/tox.20735] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 04/22/2011] [Accepted: 04/30/2011] [Indexed: 05/30/2023]
Abstract
Coumestrol is one of a few biologically active substances present in leguminous plants, which are widely used as fodder for ruminants. Depending on the doses, coumestrol acts on the reproductive processes as an estrogen-like factor or antiestrogen to evoke a decrease in ovulation frequency, elongation of estrous cycle duration. The aim of the current investigations was to study the influence of coumestrol on secretory function of luteal cells obtained from first trimester of pregnant cows. Luteal cells (2.5 × 10(5) /mL) from 3rd to 5th, 6th to 8th, and 9th to 12th week of pregnancy were preincubated for 24 h and incubated with coumestrol (1 × 10(-6) M) for successive 48 h and the medium concentrations of progesterone (P4), oxytocin (OT), prostaglandin (PG) E2 and F2α were determined. Moreover, the expression of mRNA for neurophysin-I/oxytocin (NP-I/OT; precursor of OT) and peptidyl-glycine-α-amidating mono-oxygenase (PGA, an enzyme responsible for post-translational OT synthesis) was determined after 8 h of treatment. Coumestrol did not affect P4 secretion but increased the secretion of OT from the cells collected at all stages of gestation studied. Hence, the ratio of P4 to OT was markedly decreased. Simultaneously, coumestrol increased the expression of NP-I/OT mRNA during 9th to 12th weeks of pregnancy, and mRNA for PGA during 3rd to 5th and 9th to 12th weeks of gestation. Furthermore, coumestrol decreased PGE2 secretion from luteal cells in all studied stages of pregnancy, while it affected PGF2α metabolite (PGFM) concentration only from week 3 to 5 of pregnancy. Obtained results suggest that coumestrol impairs secretory function of the corpus luteum (CL) and this way it can affect the maintenance of pregnancy in the cow.
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Affiliation(s)
- J Młynarczuk
- Institute of Animal Reproduction and Food Research Polish Academy of Sciences, Olsztyn, Poland
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16
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Butt MS, Pasha I, Sultan MT, Randhawa MA, Saeed F, Ahmed W. Black Pepper and Health Claims: A Comprehensive Treatise. Crit Rev Food Sci Nutr 2013; 53:875-86. [DOI: 10.1080/10408398.2011.571799] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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17
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Long M, Krüger T, Ghisari M, Bonefeld-Jørgensen EC. Effects of selected phytoestrogens and their mixtures on the function of the thyroid hormone and the aryl hydrocarbon receptor. Nutr Cancer 2012; 64:1008-19. [PMID: 22966911 DOI: 10.1080/01635581.2012.711419] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Phytoestrogens (PEs) are natural plant components, which can induce biologic responses in vertebrates by mimicking or blocking the actions of natural hormones or influencing the hormone production in the body. This study investigated the effect of different mixtures composed of food-relevant PEs on the thyroid hormone (TH) system assessing the proliferation of the 3,3',5-triiodi-L-thryonine (T3) dependent rat pituitary GH3 cells using the T-screen assay, and the effect on the aryl hydrocarbon receptor (AhR) transactivation using an AhR-luciferase reporter gene assay. Most tested PEs and their mixtures showed effect on both the TH and AhR system. Single isoflavonoid metabolites and their mixture and coumestrol induced GH3 cell growth and AhR transactivity dose-dependently. Isoflavonoid metabolites elicited an additive effect on the T3-dependent GH3 cell growth, and a synergistic effect on the AhR transactivity. In conclusion, nutrition-relevant PEs, alone and in mixture may possess endocrine-disrupting potential by interfering with TH and AhR functions, which need to be considered when assessing the effects on human health.
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Affiliation(s)
- Manhai Long
- Centre for Arctic Health & Unit of Cellular and Molecular Toxicology, Department of Public Health, Aarhus University, Aarhus, Denmark.
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18
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Wall RJ, He G, Denison MS, Congiu C, Onnis V, Fernandes A, Bell DR, Rose M, Rowlands JC, Balboni G, Mellor IR. Novel 2-amino-isoflavones exhibit aryl hydrocarbon receptor agonist or antagonist activity in a species/cell-specific context. Toxicology 2012; 297:26-33. [PMID: 22507882 DOI: 10.1016/j.tox.2012.03.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Revised: 03/23/2012] [Accepted: 03/29/2012] [Indexed: 11/16/2022]
Abstract
The aryl hydrocarbon receptor (AhR) mediates the induction of a variety of xenobiotic metabolism genes. Activation of the AhR occurs through binding to a group of structurally diverse compounds, most notably dioxins, which are exogenous ligands. Isoflavones are part of a family which include some well characterised endogenous AhR ligands. This paper analysed a novel family of these compounds, based on the structure of 2-amino-isoflavone. Initially two luciferase-based cell models, mouse H1L6.1c2 and human HG2L6.1c3, were used to identify whether the compounds had AhR agonistic and/or antagonistic properties. This analysis showed that some of the compounds were weak agonists in mouse and antagonists in human. Further analysis of two of the compounds, Chr-13 and Chr-19, was conducted using quantitative real-time PCR in rat H4IIE and human MCF-7 cells. The results indicated that Chr-13 was an agonist in rat but an antagonist in human cells. Chr-19 was shown to be an agonist in rat but more interestingly, a partial agonist in human. Luciferase induction results not only revealed that subtle differences in the structure of the compound could produce species-specific differences in response but also dictated the ability of the compound to be an AhR agonist or antagonist. Substituted 2-amino-isoflavones represent a novel group of AhR ligands that must differentially interact with the AhR ligand binding domain to produce their species-specific agonist or antagonist activity and future ligand binding analysis and docking studies with these compounds may provide insights into the differential mechanisms of action of structurally similar compounds.
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Affiliation(s)
- Richard J Wall
- School of Biology, University Park, University of Nottingham, Nottingham NG7 2RD, UK
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19
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Nishiumi S, Hosokawa K, Anetai M, Shibata T, Mukai R, Yoshida KI, Ashida H. Antagonistic effect of the Ainu-selected traditional beneficial plants on the transformation of an aryl hydrocarbon receptor. J Food Sci 2012; 77:C420-9. [PMID: 22394227 DOI: 10.1111/j.1750-3841.2011.02611.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
UNLABELLED Transformation of an aryl hydrocarbon receptor (AhR) is the initial step to express the multiple toxicity of halogenated and polycyclic aromatic hydrocarbons (HAHs and PAHs) including dioxins. Therefore, it has been suggested that suppression of the transformation induced by HAHs and PAHs leads to reduce their toxicological effects. In this study, the antagonistic effect of 110 indigenous plants (192 plant parts) used as medicine and/or food by the Ainu on the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced AhR transformation was investigated. Of these, a stalk of Aralia elata (Miq.) Seemann and a bark of Fraxinus mandshurica Rupr. var. japonica Maxim. exhibited the strong antagonistic effect in a dose-dependent manner. An antioxidative activity and polyphenol content were also measured, and the strong correlation (r= 0.96) between these two parameters could be confirmed. However, correlation coefficients of the antagonistic effect of 192 extracts compared to their antioxidative activity and polyphenol content were 0.17 and 0.20, respectively. These results suggest that the Ainu-selected traditional beneficial plants are useful source for findings of novel AhR antagonists, and the antagonistic activity of these plants may be independent on their antioxidative activity and polyphenol content. PRACTICAL APPLICATION Our findings lead to discovery of the valuable plants used by the Ainu and the novel active compounds useful for human's life, and furthermore, may contribute to the development of new medicines and functional foods.
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Affiliation(s)
- Shin Nishiumi
- Department of Agrobioscience, Graduate School of Agricultural Science, Kobe University, Nada-ku, Kobe, Hyogo, Japan
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20
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Uchi H, Tokunaga S, Mitoma C, Shibata S, Hamada N, Nakanishi Y, Kajiwara J, Yoshimura T, Furue M. A clinical trial of kampo formulae for the treatment of symptoms of yusho, a poisoning caused by dioxins and related organochlorine compounds. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2011; 2011:589724. [PMID: 19996156 PMCID: PMC3136710 DOI: 10.1093/ecam/nep209] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2009] [Accepted: 11/12/2009] [Indexed: 11/29/2022]
Abstract
The objective of this study was to evaluate the effectiveness of traditional herbal medicines (Kampo) on the symptoms of Yusho. Yusho is a mass food poisoning that was caused by ingestion of rice oil contaminated with dioxins and related organochlorines in 1968. Patients with Yusho suffer from skin symptoms (acneform eruptions, liability to suppuration and pigmentation), respiratory symptoms (cough and expectoration of sputum), neurological symptoms (numbness and paresthesia of extremities), arthralgia and general fatigue, and no effective treatment has yet been developed. In this clinical trial, four Kampo formulae (Bakumondo-to, Keigai-rengyo-to, Gosha-jinki-gan and Hochu-ekki-to) were administered to four representative Yusho symptoms (respiratory, skin, neurological symptoms and general fatigue), respectively. Twenty-seven Yusho patients were enrolled and two formulae were administered to each patient for half-a-year each. The effectiveness of Kampo formulae was estimated by changes in the intensity of symptoms measured by a visual analogue scale (VAS) of 100 mm recorded at baseline and after administration of each formula. The influence of Kampo formulae on patients' quality of life (QOL) was also assessed by the SF-36 (NBS). Twenty-five patients completed the treatment. Bakumondo-to significantly improved respiratory symptoms as well as patients' QOL in the context of vitality, compared with other formulae. In contrast, Hochu-ekki-to impaired patients' QOL in the context of physical functioning and vitality, compared with other formulae. This study demonstrated for the first time that a Kampo formula Bakumondo-to is useful for treating respiratory symptoms caused by dioxins.
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Affiliation(s)
- Hiroshi Uchi
- Research and Clinical Center for Yusho and Dioxin, Kyushu University Hospital, Fukuoka 812-8582, Japan
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21
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Takemura H, Nagayoshi H, Matsuda T, Sakakibara H, Morita M, Matsui A, Ohura T, Shimoi K. Inhibitory effects of chrysoeriol on DNA adduct formation with benzo[a]pyrene in MCF-7 breast cancer cells. Toxicology 2010; 274:42-8. [DOI: 10.1016/j.tox.2010.05.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Revised: 05/19/2010] [Accepted: 05/19/2010] [Indexed: 10/19/2022]
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22
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Potential health-modulating effects of isoflavones and metabolites via activation of PPAR and AhR. Nutrients 2010; 2:241-79. [PMID: 22254019 PMCID: PMC3257647 DOI: 10.3390/nu2030241] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Accepted: 02/23/2010] [Indexed: 12/24/2022] Open
Abstract
Isoflavones have multiple actions on cell functions. The most prominent one is the activation of estrogen receptors. Other functions are often overlooked, but are equally important and explain the beneficial health effects of isoflavones. Isoflavones are potent dual PPARα/γ agonists and exert anti-inflammatory activity, which may contribute to the prevention of metabolic syndrome, atherosclerosis and various other inflammatory diseases. Some isoflavones are potent aryl hydrocarbon receptor (AhR) agonists and induce cell cycle arrest, chemoprevention and modulate xenobiotic metabolism. This review discusses effects mediated by the activation of AhR and PPARs and casts a light on the concerted action of isoflavones.
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23
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Swedenborg E, Pongratz I, Gustafsson JA. Endocrine disruptors targeting ERbeta function. ACTA ACUST UNITED AC 2009; 33:288-97. [PMID: 20050941 DOI: 10.1111/j.1365-2605.2009.01025.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Endocrine disruptive chemicals (EDCs) circulating in the environment constitute a risk to ecosystems, wildlife and human health. Oestrogen receptor (ER) alpha and beta are targeted by various kinds of EDCs but the molecular mechanisms and long-term consequences of exposure are largely unknown. Some biological effects of EDCs are mediated by the aryl hydrocarbon receptor (AhR), which is a key player in the cellular defence against xenobiotic substances. Adding complexity to the picture, there is also accumulating evidence that AhR-ER pathways have an intricate interplay at multiple levels. In this review, we discuss some EDCs that affect the oestrogen pathway by targeting ERbeta. Furthermore, we describe some effects of AhR activities on the oestrogen system. Mechanisms as well as potential adverse effects on human health are discussed.
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Affiliation(s)
- E Swedenborg
- Department of Biosciences and Nutrition, Karolinska Institutet at Novum, Huddinge, Sweden.
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24
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Kanematsu M, Hayashi A, Denison MS, Young TM. Characterization and potential environmental risks of leachate from shredded rubber mulches. CHEMOSPHERE 2009; 76:952-8. [PMID: 19450864 PMCID: PMC2735888 DOI: 10.1016/j.chemosphere.2009.04.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Revised: 04/06/2009] [Accepted: 04/12/2009] [Indexed: 05/22/2023]
Abstract
In order to determine whether shredded rubber mulches (RM) pose water quality risks when used in stormwater best management practices (BMPs) such as bioretention basins, batch leaching tests were conducted to identify and quantify constituents in leachates from RM such as metal ions, nutrients, total organic carbon (TOC), and aryl hydrocarbon receptor (AhR) activity (determined by the chemically activated luciferase gene expression (CALUX) bioassay) at varied temperature and initial pH values. The results indicate that aqueous extracts of RM contain high concentrations of zinc (Zn) compared with wood mulches (WM), and its concentration increased at lower pH and higher temperature. Although methanol extracts of RM displayed high AhR activity, none of the aqueous extracts of RM had significant activity. Hence, while unknown constituents that have significant AhR activity are present in RM, they appear to be not measurably extracted by water under environmental conditions relevant for stormwater (5
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Affiliation(s)
- Masakazu Kanematsu
- Department of Civil and Environmental Engineering, University of California - Davis
| | - Ai Hayashi
- Department of Environmental Toxicology, University of California - Davis, One Shields Avenue, Davis, California, 95616
| | - Michael S. Denison
- Department of Environmental Toxicology, University of California - Davis, One Shields Avenue, Davis, California, 95616
| | - Thomas M. Young
- Department of Civil and Environmental Engineering, University of California - Davis
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25
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Ishida T, Takeda T, Koga T, Yahata M, Ike A, Kuramoto C, Taketoh J, Hashiguchi I, Akamine A, Ishii Y, Yamada H. Attenuation of 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity by resveratrol: a comparative study with different routes of administration. Biol Pharm Bull 2009; 32:876-81. [PMID: 19420757 DOI: 10.1248/bpb.32.876] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The activation of aryl hydrocarbon receptor with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is known to be antagonized by co-treatment with resveratrol. However, such a protective effect has been suggested from studies using subcutaneous injection of this polyphenol. To evaluate the practical usefulness of resveratrol, this study examined the protective effect of oral resveratrol on the sub-acute toxic effects of TCDD in C57BL/6J mice. A TCDD-induced wasting syndrome was not alleviated by treating mice for 28 d with oral resveratrol. However, subcutaneous injection of resveratrol for 5 d significantly improved the symptoms. Neither oral nor subcutaneous administration of resveratrol alleviated TCDD-induced hepatomegaly and thymic atrophy. Steatosis produced by TCDD was markedly counteracted by co-treatment with oral resveratrol, whereas resveratrol injected subcutaneously had no effect. The reason for the lack of protective effect via the latter dosing route was assumed to be due to the minor accumulation of hepatic lipids 5 d after TCDD treatment. To clarify the mechanisms, the activity of ethoxyresorufin O-deethylase and the content of thiobarbituric acid-reactive substances in the liver were measured. Both indices increased by TCDD treatment were significantly suppressed by subcutaneous injection of resveratrol. In contrast, oral resveratrol failed to rescue them. In agreement with the greater protective effects of subcutaneously-injected resveratrol, pharmacokinetic studies indicated that the area under the curve extrapolated to infinity (AUC(infinity)) was 8.2-times greater following subcutaneous injection compared with oral administration. These data suggest that 1) oral resveratrol is attractive candidate as an agent capable of combating dioxin toxicity and 2) increasing the bioavailability of this polyphenol enhances its protective effect.
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Affiliation(s)
- Takumi Ishida
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
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26
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Matsumoto S, Jin M, Dewa Y, Nishimura J, Moto M, Murata Y, Shibutani M, Mitsumori K. Suppressive effect of Siraitia grosvenorii extract on dicyclanil-promoted hepatocellular proliferative lesions in male mice. J Toxicol Sci 2009; 34:109-18. [PMID: 19182440 DOI: 10.2131/jts.34.109] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Dicyclanil (DC) generates reactive oxygen species (ROS) due to Cyp1a1 induction, and DNA damage caused by oxidative stress is probably involved in hepatocarcinogenesis in mice. To clarify the modifying effect of the Siraitia grosvenorii extract (SGE), which has antioxidative properties, we employed a 2-stage liver carcinogenesis model in partially hepatectomized male ICR mice. Mice maintained on diet containing DC at a concentration of 1,500 ppm for 9 weeks after a single intraperitoneal injection of diethylnitrosamine (DEN) at a dose of 30 mg/kg and they were given water containing 2,500 ppm of SGE for 11 weeks including 2 weeks as pre-administration on DC. SGE inhibited the induction of gamma-glutamyltranspeptidase-positive hepatocytes, lipid peroxidation, and gene expression of Cyp1a1, all of which were caused by DC. To examine whether SGE indirectly inhibits Cyp1a1 expression induced by inhibition of aryl hydrocarbon receptor (Ahr)-mediated signal transduction caused by DC, mice with high (C57BL/6J mice) and low affinities (DBA/2J mice) to Ahr were given DC-containing diet and/or SGE-containing tap water for 2 weeks. Cyp1a1 gene expression was significantly lower in C57BL/6J mice administered DC + SGE than in C57BL/6J mice administered DC alone; there was no difference in the Cyp1a1 expression between DBA/2J mice administered DC + SGE and DC alone. These results suggest that SGE suppresses the induction of Cyp1a1, leading to inhibition of ROS generation and consequently inhibited hepatocarcinogenesis, probably due to suppression of Ahr activity.
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Affiliation(s)
- Sayaka Matsumoto
- Laboratory of Veterinary Pathology, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu-shi, Tokyo 183-8509, Japan
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27
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Fukuda I, Kaneko A, Nishiumi S, Kawase M, Nishikiori R, Fujitake N, Ashida H. Structure–activity relationships of anthraquinones on the suppression of DNA-binding activity of the aryl hydrocarbon receptor induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin. J Biosci Bioeng 2009; 107:296-300. [DOI: 10.1016/j.jbiosc.2008.10.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2008] [Revised: 10/20/2008] [Accepted: 10/23/2008] [Indexed: 12/31/2022]
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28
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Veldhoen M, Hirota K, Christensen J, O'Garra A, Stockinger B. Natural agonists for aryl hydrocarbon receptor in culture medium are essential for optimal differentiation of Th17 T cells. J Exp Med 2009; 206:43-9. [PMID: 19114668 PMCID: PMC2626686 DOI: 10.1084/jem.20081438] [Citation(s) in RCA: 399] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2008] [Accepted: 12/03/2008] [Indexed: 11/04/2022] Open
Abstract
Th17 cell differentiation is dependent on interleukin (IL)-6 and transforming growth factor (TGF)-beta, and it is modulated by activation of the aryl hydrocarbon receptor (AhR). In this study, we show that differentiation of Th17 cells, but not Th1 or induced regulatory T (iT reg) cells, is increased by endogenous AhR agonists present in culture medium. Th17 development from wild-type mice is suboptimal in the presence of the AhR antagonist CH-223191, similar to the situation in AhR-deficient mice, which show attenuated IL-17 production and no IL-22 production. The presence of natural AhR agonists in culture medium is also revealed by the induction of CYP1A1, a downstream target of AhR activation. However, the most commonly used medium, RPMI, supports very low levels of Th17 polarization, whereas Iscove's modified Dulbecco's medium, a medium richer in aromatic amino acids, which give rise to AhR agonists, consistently results in higher Th17 expansion in both mouse and human cells. The relative paucity of AhR agonists in RPMI medium, coupled with the presence of factors conducive to IL-2 activation and enhanced Stat5 phosphorylation, conspire against optimal Th17 differentiation. Our data emphasize that AhR activation plays an essential part in the development of Th17 cells and provide a rational explanation for the poor in vitro polarization of Th17 cells that is reported in the majority of publications for both mouse and human cells.
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MESH Headings
- Animals
- Azo Compounds/pharmacology
- CD4-Positive T-Lymphocytes/cytology
- CD4-Positive T-Lymphocytes/drug effects
- CD4-Positive T-Lymphocytes/metabolism
- Carbazoles/pharmacology
- Cell Differentiation/drug effects
- Cell Differentiation/physiology
- Culture Media/chemistry
- Culture Media/pharmacology
- Cytochrome P-450 CYP1A1/genetics
- Gene Expression/drug effects
- Humans
- Interleukin-17/metabolism
- Interleukin-2/metabolism
- Interleukins/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Inbred Strains
- Mice, Knockout
- Nuclear Receptor Subfamily 1, Group F, Member 3
- Phosphorylation/drug effects
- Pyrazoles/pharmacology
- Receptors, Aryl Hydrocarbon/agonists
- Receptors, Aryl Hydrocarbon/antagonists & inhibitors
- Receptors, Aryl Hydrocarbon/physiology
- Receptors, Retinoic Acid/genetics
- Receptors, Thyroid Hormone/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- STAT5 Transcription Factor/metabolism
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/drug effects
- T-Lymphocyte Subsets/metabolism
- T-Lymphocytes, Helper-Inducer/cytology
- T-Lymphocytes, Helper-Inducer/drug effects
- T-Lymphocytes, Helper-Inducer/metabolism
- Tryptophan/pharmacology
- Interleukin-22
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Affiliation(s)
- Marc Veldhoen
- Division of Molecular Immunology, Medical Research Council National Institute for Medical Research, London NW7 1AA, England, UK
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Mukai M, Hayakawa K, Okamura M, Tagawa Y, Nakajima S, Saito Y, Takahashi S, Yao J, Nishimura D, Sugi M, Matsunaga M, Kitamura M. Preferential Blockade of Dioxin-Induced Activation of the Aryl Hydrocarbon Receptor by Antrodia camphorata. Biol Pharm Bull 2009; 32:1510-5. [DOI: 10.1248/bpb.32.1510] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Mai Mukai
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Kunihiro Hayakawa
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Maro Okamura
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Yasuhiro Tagawa
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Shotaro Nakajima
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Yukinori Saito
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Shuhei Takahashi
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Jian Yao
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
| | - Daisuke Nishimura
- Hokkaido Research Institute, Nissei Bio Co., Ltd
- Gene Trophology Research Institute
| | - Masahito Sugi
- Hokkaido Research Institute, Nissei Bio Co., Ltd
- Gene Trophology Research Institute
| | - Masaji Matsunaga
- Hokkaido Research Institute, Nissei Bio Co., Ltd
- Gene Trophology Research Institute
| | - Masanori Kitamura
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi
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30
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Aryl hydrocarbon receptor-mediated apoptosis of neuronal cells: A possible interaction with estrogen receptor signaling. Neuroscience 2009; 158:811-22. [DOI: 10.1016/j.neuroscience.2008.10.045] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2008] [Revised: 10/27/2008] [Accepted: 10/30/2008] [Indexed: 01/21/2023]
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31
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Amakura Y, Tsutsumi T, Sasaki K, Nakamura M, Yoshida T, Maitani T. Influence of food polyphenols on aryl hydrocarbon receptor-signaling pathway estimated by in vitro bioassay. PHYTOCHEMISTRY 2008; 69:3117-30. [PMID: 17869316 DOI: 10.1016/j.phytochem.2007.07.022] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Revised: 06/08/2007] [Accepted: 07/17/2007] [Indexed: 05/17/2023]
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that mediates the toxic and biological actions of many aromatic environmental pollutants such as dioxins. We investigated AhR activation by some vegetable constituents, including flavonoids, tannins, and related polyphenols, using an AhR-based in vitro bioassay for dioxins. Among the compounds tested, marked AhR activation was exhibited by isoflavones such as daidzein, resveratrol (a stilbene) structure, some flavanones such as naringenin, and flavones such as baicalein. On the other hand, some flavones such as apigenin, flavonols such as quercetin, and anthraquinones such as emodin, showed notable inhibitory effects on the in vitro activation of AhR induced by the dioxin [2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)]. In addition, AhR-mediated interactions between AhR and some plant extracts, including those from vegetables, fruits, herbs, and teas, were tested by using the AhR-based bioassay. Of the samples tested, some leafy green vegetables, citrus fruits, and herbs that contain food polyphenolics showed AhR-based interactions at high concentrations. On the basis of these finding, we discuss the implications of polyphenols on the AhR-signaling pathway.
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Affiliation(s)
- Yoshiaki Amakura
- College of Pharmaceutical Sciences, Matsuyama University, 4-2 Bunkyo-cho, Matsuyama, Ehime 790-8578, Japan.
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32
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Ashida H, Nishiumi S, Fukuda I. An update on the dietary ligands of the AhR. Expert Opin Drug Metab Toxicol 2008; 4:1429-47. [DOI: 10.1517/17425255.4.11.1429] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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33
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Food flavonoid aryl hydrocarbon receptor-mediated agonistic/antagonistic/synergic activities in human and rat reporter gene assays. Anal Chim Acta 2008; 637:337-45. [PMID: 19286049 DOI: 10.1016/j.aca.2008.09.054] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2008] [Revised: 09/24/2008] [Accepted: 09/24/2008] [Indexed: 02/01/2023]
Abstract
Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor mediating the adverse effects of dioxins and polycyclic aromatic hydrocarbons (PAHs). In this study, we investigated the genetic-, time-, dose-, species- and tissue-dependent AhR-mediated agonistic/antagonistic activities of three food flavonoids: quercetin, chrysin and genistein. To that end, four stably transfected cell lines were used in cell-based luciferase reporter gene assays: three lines were transformed with the ptKLuc vector harbouring four dioxin-responsive elements (DREs) upstream of the thymidine kinase promoter and the luciferase gene (HepG2-Luc, T-47D-Luc and H4IIE-ULg). The fourth is a patented cell line transformed with a different construct: H4IIE DR-CALUX((R)). Both H4IIE cells were compared for their genetic construction. Human hepatoma (HepG2-Luc) and human breast tumour (T-47D-Luc) cells were compared for tissue-dependent effects. Rat hepatoma (H4IIE-ULg) and human hepatoma (HepG2-Luc) cells were compared for species-dependent activities. We concluded that quercetin, chrysin and genistein act in a time-, dose-, species- and tissue-specific way. For example, genistein displayed agonistic activities when exposed to rat hepatoma cells during 6h but not after 24h. Flavonoids displayed agonistic/antagonistic activities in human breast tumour cells, depending on the exposure time, while in human hepatoma cells, only antagonistic activities of flavonoids were measured. In addition, we report, in all the cells, a synergy between an isoflavone and two food contaminants; the 2,3,7,8-tetrachlorodibenzo-p-dioxin and 3-methylcholanthrene, a PAH. In rat cells, this synergy occurred when cells were exposed to flavonoids and contaminant for 6h, while it was observed in human cells only after 24h.
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Mukai M, Kasai A, Hiramatsu N, Hayakawa K, Okamura M, Tagawa Y, Yao J, Nakamura T, Kitamura M. Blockade of the aryl hydrocarbon receptor pathway triggered by dioxin, polycyclic aromatic hydrocarbons and cigarette smoke by Phellinus linteus. Biol Pharm Bull 2008; 31:1888-93. [PMID: 18827349 DOI: 10.1248/bpb.31.1888] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Environmental pollutants including halogenated and polycyclic aromatic hydrocarbons activate the aryl hydrocarbon receptor (AhR) and thereby cause a wide range of pathological changes. Development of AhR antagonists will be useful for prevention and treatment of diseases related to AhR activation. Towards this end, we aimed in the present study at seeking for potential inhibitors of the AhR pathway in mycelial extracts using the dioxin responsive element-based sensing via secreted alkaline phosphatase (DRESSA). Through the screening of 13 mycelia, extracts prepared from Phellinus linteus, Cordyceps militaris and Hericium erinaceum inhibited activation of AhR by 2,3,7,8-tetrachlorodibenzo-p-dioxin, benzo[a]pyrene or 3-methylcholanthrene. Subsequent studies revealed that only Phellinus linteus suppressed activation of AhR and AhR-dependent gene expression triggered by all of these agonists. Cigarette smoke is known to contain a number of halogenated and polycyclic aromatic hydrocarbons. We found that Phellinus linteus has the potential to block activation of AhR and AhR-dependent gene expression triggered by cigarette smoke. Furthermore, the inhibitory effect of Phellinus linteus on the AhR pathway was independent of; 1) depression of AhR or AhR nuclear translocator, and 2) induction of AhR repressor. We conclude that Phellinus linteus contains potent inhibitor(s) of AhR activation and may be useful for prevention of pathologies associated with aberrant activation of AhR.
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Affiliation(s)
- Mai Mukai
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo, Yamanashi 409-3898, Japan
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A human intervention study with foods containing natural Ah-receptor agonists does not significantly show AhR-mediated effects as measured in blood cells and urine. Chem Biol Interact 2008; 176:19-29. [PMID: 18762178 DOI: 10.1016/j.cbi.2008.07.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2008] [Revised: 07/22/2008] [Accepted: 07/28/2008] [Indexed: 11/22/2022]
Abstract
Binding and activation of the aryl hydrocarbon receptor (AhR) is thought to be an essential step in the toxicity of the environmental pollutants dioxins and dioxin-like PCBs. However, also a number of natural compounds, referred to as NAhRAs (natural Ah-receptor agonists), which are present in, for example, fruits and vegetables, can bind and activate this receptor. To study their potential effects in humans, we first investigated the effect of the prototypical AhR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on gene expression in ex vivo exposed freshly isolated human lymphocytes, and compared the resulting gene expression profile with those caused by the well-known NAhRA indolo[3,2-b]carbazole (ICZ), originating from cruciferous vegetables, and by a hexane extract of NAhRA-containing grapefruit juice (GJE). Only ICZ induced a gene expression profile similar to TCDD in the lymphocytes, and both significantly up-regulated CYP1B1 and TIPARP (TCDD-inducible poly (ADP-ribose) polymerase) mRNA. Next, we performed a human intervention study with NAhRA-containing cruciferous vegetables and grapefruit juice. The expression of the prototypical AhR-responsive genes CYP1A1, CYP1B1 and NQO1 in whole blood cells and in freshly isolated lymphocytes was not significantly affected. Also enzyme activities of CYP1A2, CYP2A6, N-acetyltransferase 2 (NAT2) and xanthine oxidase (XO), as judged by caffeine metabolites in urine, were unaffected, except for a small down-regulation of NAT2 activity by grapefruit juice. Examination of blood plasma with DR CALUX showed a 12% increased AhR agonist activity 3 and 24 h after consumption of cruciferous vegetables, but did not show a significant effect of grapefruit juice consumption. We conclude that intake of NAhRAs from food may result in minor AhR-related effects measurable in human blood and urine.
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Connor KT, Harris MA, Edwards MR, Budinsky RA, Clark GC, Chu AC, Finley BL, Rowlands JC. AH receptor agonist activity in human blood measured with a cell-based bioassay: evidence for naturally occurring AH receptor ligands in vivo. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2008; 18:369-80. [PMID: 17912254 DOI: 10.1038/sj.jes.7500607] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2006] [Accepted: 05/25/2007] [Indexed: 05/17/2023]
Abstract
In the present study, an aryl hydrocarbon receptor (AHR)-driven reporter gene bioassay was used to measure the activity, measured as an induction equivalent (IEQ) as compared to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), or IEQ concentration in human blood samples from 10 volunteers under different dietary regimens. Blood concentrations of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and polychlorinated biphenyls (PCBs), as determined by analytical chemistry (HR-GC/MS), and expressed as toxic equivalents (TEQs) with the use of TCDD equivalency factors (TEFs), were within a range that has been reported in the general US population, ranging from 0.022 to 0.119 ppt (whole blood basis). However, the human blood IEQ measured directly via bioassay ranged from 13.4 to 218 ppt (whole blood basis). These order of magnitude greater IEQs compared to the TEQs for dioxins, furans, and certain PCBs suggests that human blood contains a relatively high level of AHR agonists able to activate the CYP1A1 dioxin response element (DRE)-linked reporter gene bioassay and that this AHR activity is not accounted for by PCDDs/Fs and dioxin-like PCBs based on standard HR-GC/MS and TEF analysis. When study participants switched from a "baseline" to a high-vegetable diet, increases in bioassay IEQ were observed that were statistically significant (P<0.05). In addition, IEQ activity was elevated above levels observed following dietary intervention in two subjects given indole-3-carbinol (I3C) supplements. We conclude that a substantial portion of the IEQ activity occurred as a result of the increased intake of natural AHR agonists (NAHRAs) present in many fruits, vegetables. and herbs. Our findings also suggest that dietary NAHRAs constitute a substantial daily dietary intake of AHR-active compounds, and these NAHRAs could influence AHR status in humans and play a role in a basal level of AHR activation.
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De Waard W, Aarts J, Peijnenburg A, De Kok T, Van Schooten FJ, Hoogenboom L. Ah receptor agonist activity in frequently consumed food items. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2008; 25:779-87. [DOI: 10.1080/02652030701798880] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Jang JY, Park D, Shin S, Jeon JH, Choi BI, Joo SS, Hwang SY, Nahm SS, Kim YB. Antiteratogenic effect of resveratrol in mice exposed in utero to 2,3,7,8-tetrachlorodibenzo-p-dioxin. Eur J Pharmacol 2008; 591:280-3. [PMID: 18571640 DOI: 10.1016/j.ejphar.2008.05.033] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2008] [Revised: 04/21/2008] [Accepted: 05/20/2008] [Indexed: 11/17/2022]
Abstract
The effect of resveratrol, an aryl hydrocarbon receptor antagonist, on the teratogenicity induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was investigated. Pregnant C57BL/6J mice were orally administered resveratrol (50 mg/kg) for 6 consecutive days, from gestational day (GD) 8 to GD13, followed by an oral challenge with TCDD (14 mug/kg) on GD12. TCDD caused severe fetal malformations including cleft palate (40.7%), renal pelvic dilatation (100%, mean score 3.060), and ureteric dilatation (100%, mean score 3.210) and tortuosity (95.1%). Resveratrol significantly reduced both the incidence of TCDD-induced cleft palate to 18.4% and the degrees of renal pelvic and ureteric dilatations caused by TCDD. The results suggest that pretreatment with resveratrol might bring a beneficial outcome for reducing the incidence and severity of fetal malformations caused by TCDD exposure in utero.
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Affiliation(s)
- Ja Young Jang
- College of Veterinary Medicine and Research Institute of Veterinary Medicine, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea
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Kasai A, Hiramatsu N, Hayakawa K, Yao J, Kitamura M. Blockade of the dioxin pathway by herbal medicine Formula Bupleuri Minor: identification of active entities for suppression of AhR activation. Biol Pharm Bull 2008; 31:838-46. [PMID: 18451504 DOI: 10.1248/bpb.31.838] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Environmental pollutants including dioxins activate the aryl hydrocarbon receptor (AhR) and cause a wide range of pathologies. Development of AhR antagonists will be useful for prevention and treatment of the diseases related to AhR activation. Towards this goal, we aimed at seeking for potential AhR antagonists in herbal medicines using the dioxin responsive element-based sensing via secreted alkaline phosphatase (DRESSA). Through initial rough screening, 4 formulae were selected from 20 herbal medicines and subjected to the second, detailed screening. We found that only Formula bupleuri minor (TJ-9) significantly inhibited activation of AhR by 2,3,7,8-tetrachlorodibenzo-p-dioxin. Among 7 raw herb extracts in TJ-9, Glycyrrhizae Radix and Scutellariae Radix were responsible for the antagonistic effect of TJ-9 against dioxin. Some constituents including Bupleuri Radix and Zingiberis Rhizoma rather activated AhR. Among 12 major constituents of Glycyrrhizae Radix and Scutellariae Radix, we identified that licopyranocoumarin, glycyrrhizic acid and genistein in Glycyrrhizae Radix and baicalein, wogonin and daidzein in Scutellariae Radix had substantial antagonistic effects on AhR. Among these, baicalein most effectively blocked activation of AhR triggered by cigarette smoke, a strong activator of AhR. The antagonistic substances identified here may be useful for prevention from diseases associated with aberrant activation of AhR.
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Affiliation(s)
- Ayumi Kasai
- Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Shimokato 1110, Chuo, Yamanashi 409-3898, Japan
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Bohonowych JES, Zhao B, Timme-Laragy A, Jung D, Di Giulio RT, Denison MS. Newspapers and newspaper ink contain agonists for the ah receptor. Toxicol Sci 2008; 102:278-90. [PMID: 18203687 PMCID: PMC2855230 DOI: 10.1093/toxsci/kfn011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Ligand-dependent activation of the aryl hydrocarbon receptor (AhR) pathway leads to a diverse array of biological and toxicological effects. The best-studied ligands for the AhR include polycyclic and halogenated aromatic hydrocarbons, the most potent of which is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). However, as new AhR ligands are identified and characterized, their structural and physiochemical diversity continues to expand. Our identification of AhR agonists in crude extracts from diverse materials raises questions as to the magnitude and extent of human exposure to AhR ligands through normal daily activities. We have found that solvent extracts of newspapers from countries around the world stimulate the AhR signaling pathway. AhR agonist activity was observed for dimethyl sulfoxide (DMSO), ethanol, and water extracts of printed newspaper, unprinted virgin paper, and black printing ink, where activation of luciferase reporter gene expression was transient, suggesting that the AhR active chemical(s) was metabolically labile. DMSO and ethanol extracts also stimulated AhR transformation and DNA binding, and also competed with [(3)H]TCDD for binding to the AhR. In addition, DMSO extracts of printed newspaper induced cytochrome P450 1A associated 7-ethoxyresorufin-O-deethylase activity in zebrafish embryos in vivo. Although the responsible bioactive chemical(s) remain to be identified, our results demonstrate that newspapers and printing ink contain relatively potent metabolically labile agonists of the AhR. Given the large amount of recycling and reprocessing of newspapers throughout the world, release of these easily extractable AhR agonists into the environment should be examined and their potential effects on aquatic organisms assessed.
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Affiliation(s)
- Jessica E S Bohonowych
- Department of Environmental Toxicology, University of California, Davis, California 95616, USA
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Kasai A, Hiramatsu N, Hayakawa K, Yao J, Kitamura M. Direct, continuous monitoring of air pollution by transgenic sensor mice responsive to halogenated and polycyclic aromatic hydrocarbons. ENVIRONMENTAL HEALTH PERSPECTIVES 2008; 116:349-354. [PMID: 18335102 PMCID: PMC2265056 DOI: 10.1289/ehp.10722] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Accepted: 12/19/2007] [Indexed: 05/26/2023]
Abstract
BACKGROUND The aryl hydrocarbon receptor (AhR, also called the dioxin receptor) plays crucial roles in toxicologic responses of animals to environmental pollutants, especially to halogenated and polycyclic aromatic hydrocarbons. To achieve direct, continuous risk assessment of air pollution using biological systems, we generated transgenic sensor mice that produce secreted alkaline phosphatase (SEAP) under the control of AhR. METHODS To characterize responses of the mice to AhR agonists, sensor mice were orally administered 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3-methylcholanthrene (3MC), benzo[a]pyrene (B[a]P), or beta-naphthoflavone (BNF), and serum levels of SEAP were evaluated. To monitor air pollution caused by cigarette smoke, we placed the mice each day in an experimental smoking room, and evaluated activity of serum SEAP for up to 4 days. Activation of AhR in individual organs was also examined by reverse transcription-polymerase chain reaction (RT-PCR) analysis of SEAP. RESULTS In response to oral exposure to TCDD, sensor mice exhibited dramatic and sustained activation of AhR. The mice also responded sensitively to 3MC, B[a]P, and BNF. Activation of AhR was dose dependent, and the liver was identified as the main responding organ. After exposure to the smoking environment, sensor mice consistently exhibited transient, reversible activation of AhR. RT-PCR analysis of SEAP revealed that activation of AhR occurred predominantly in the lung. CONCLUSION We are the first laboratory to demonstrate successfully direct, comprehensive monitoring of air pollution using genetically engineered mammals. The established system would be useful for real risk assessment of halogenated and polycyclic aromatic hydrocarbons in the air, especially in smoking environments.
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Affiliation(s)
| | | | | | | | - Masanori Kitamura
- Address correspondence to M. Kitamura, Department of Molecular Signaling, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Shimokato 1110, Chuo, Yamanashi 409-3898, Japan. Telephone: 81-55-273-8054. Fax: 81-55-273-8054. E-mail:
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Saracino MR, Lampe JW. Phytochemical regulation of UDP-glucuronosyltransferases: implications for cancer prevention. Nutr Cancer 2008; 59:121-41. [PMID: 18001207 DOI: 10.1080/01635580701458178] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Uridine 5'-diphospho-glucuronosyltransferases (UGTs) are Phase II biotransformation enzymes that metabolize endogenous and exogenous compounds, some of which have been associated with cancer risk. Many phytochemicals have been shown to induce UGTs in humans, rodents, and cell culture systems. Because UGTs maintain hormone balance and facilitate excretion of potentially carcinogenic compounds, regulation of their expression and activity may affect cancer risk. Phytochemicals regulate transcription factors such as the nuclear factor-erythroid 2-related factor 2 (Nrf2), aryl hydrocarbon, and pregnane X receptors as well as proteins in several signal transduction cascades that converge on Nrf2 to stimulate UGT expression. This induction can be modified by several factors, including phytochemical dose and bioavailability and interindividual variation in enzyme expression. In this review, we summarize the knowledge of dietary modulation of UGTs, particularly by phytochemicals, and discuss the potential mechanisms by which phytochemicals regulate UGT transcription.
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Ishida T, Ishizaki M, Tsutsumi S, Ishii Y, Yamada H. Piperine, a Pepper Ingredient, Improves the Hepatic Increase in Free Fatty Acids Caused by 2,3,7,8-Tetrachlorodibenzo-p-dioxin. ACTA ACUST UNITED AC 2008. [DOI: 10.1248/jhs.54.551] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Takumi Ishida
- Graduate School of Pharmaceutical Sciences, Kyushu University
| | - Mizuho Ishizaki
- Graduate School of Pharmaceutical Sciences, Kyushu University
| | - Siho Tsutsumi
- Graduate School of Pharmaceutical Sciences, Kyushu University
| | - Yuji Ishii
- Graduate School of Pharmaceutical Sciences, Kyushu University
| | - Hideyuki Yamada
- Graduate School of Pharmaceutical Sciences, Kyushu University
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Medjakovic S, Jungbauer A. Red clover isoflavones biochanin A and formononetin are potent ligands of the human aryl hydrocarbon receptor. J Steroid Biochem Mol Biol 2008; 108:171-7. [PMID: 18060767 DOI: 10.1016/j.jsbmb.2007.10.001] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2007] [Revised: 10/11/2007] [Accepted: 10/15/2007] [Indexed: 12/26/2022]
Abstract
Aryl hydrocarbon receptor (AhR) activation affects the cell cycle and drives cells to apoptosis. Thus, selective AhR modulators (SAhRMs) have previously been implicated in cancer therapy and prevention, particularly for hormone-dependent cancers. In the present study, isoflavones a remedy used to ameliorate menopausal complaints were tested for their potential in transactivating AhR in order to investigate the biological function of red clover isoflavones. The results were compared to the transactivation potentials of other flavonoids and plant-derived indole compounds. We found that the isoflavones biochanin A and formononetin were potent AhR agonists in vitro, with EC(50) values of 2.5 x 10(-7) and 1.3 x 10(-7)mol/l, respectively. These isoflavones are 10 times more potent compared to the indole compounds indole-3-carbinol and diindolylmethane, publicised as powerful AhR agonists with EC(50) values of 5.8 x 10(-6) and 1.1 x 10(-6)mol/l, respectively. Because activated AhR crosstalks with estrogen receptor alpha, future risk-benefit assessments of isoflavones should take into consideration their AhR transactivating potential.
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Affiliation(s)
- S Medjakovic
- Department of Biotechnology, University of Natural Resources and Applied Life Sciences Vienna, Muthgasse 18, Vienna, Austria
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45
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Nishiumi S, Yoshida KI, Ashida H. Curcumin suppresses the transformation of an aryl hydrocarbon receptor through its phosphorylation. Arch Biochem Biophys 2007; 466:267-73. [PMID: 17880909 DOI: 10.1016/j.abb.2007.08.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Revised: 07/27/2007] [Accepted: 08/01/2007] [Indexed: 11/19/2022]
Abstract
Halogenated and polycyclic aromatic hydrocarbons induce diverse biochemical responses through the transformation of a cytosolic aryl hydrocarbon receptor (AhR). In mouse hepatoma Hepa-1c1c7 cells, curcumin, a yellow pigment of Curcuma longa, did not inhibit the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced translocation of the AhR into the nucleus, but rather accelerated it. In the nucleus, curcumin inhibited the TCDD-induced heterodimerization of the AhR with an AhR nuclear translocator (Arnt), an essential partner for the transformation, and also dose-dependently inhibited the TCDD-evoked phosphorylation of both the AhR and Arnt. Moreover, curcumin significantly inhibited the TCDD-induced activation of protein kinase C (PKC), which is involved in the transformation, decreased the TCDD-induced DNA-binding activity of the AhR/Arnt heterodimer, and downregulated CYP1A1 expression. In a cell-free system, curcumin inhibited the binding of 3-methylcholanthrene, an AhR agonist, to the receptor. These results indicate that curcumin is able to bind to the AhR as a ligand, but suppresses its transformation by inhibiting the phosphorylation of AhR and Arnt, probably by PKC.
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Affiliation(s)
- Shin Nishiumi
- Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
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Fukuda I, Mukai R, Kawase M, Yoshida KI, Ashida H. Interaction between the aryl hydrocarbon receptor and its antagonists, flavonoids. Biochem Biophys Res Commun 2007; 359:822-7. [PMID: 17560542 DOI: 10.1016/j.bbrc.2007.05.199] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2007] [Accepted: 05/31/2007] [Indexed: 10/23/2022]
Abstract
Flavonoids have been reported to be dietary antagonists of an aryl hydrocarbon receptor (AhR). However, little is known about the molecular mechanism on their antagonistic effects. In this study, the inhibitory effect of flavonoids on ligand binding to the AhR and interaction between flavonoids and the AhR complex (AhRc) were investigated in each flavonoid subclass. Flavone, flavonol, and flavanone but not catechin inhibited the specific binding between the AhR and 3-methylcholanthrene dose-dependently, indicating that the former three subclasses possibly act as competitive antagonists of the AhR. However, catechin in addition to the former three subclasses directly interacted with the AhRc by surface plasmon resonance analysis. The dissociation constant values showed an inverse correlation with the suppressive effect on the DNA binding activity. These results suggest that flavone, flavonol, and flavanone act as competitive antagonists of the AhR, while catechin associates with the AhRc and indirectly exhibits its antagonistic effects.
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Affiliation(s)
- Itsuko Fukuda
- Research Center for Food Safety and Security, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan.
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Petersen SL, Krishnan S, Hudgens ED. The aryl hydrocarbon receptor pathway and sexual differentiation of neuroendocrine functions. Endocrinology 2006; 147:S33-42. [PMID: 16690800 DOI: 10.1210/en.2005-1157] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Historically, much of the research on health effects of environmental pollutants focused on ascertaining whether compounds were carcinogenic. More recent findings show that environmental contaminants also exert insidious effects by disrupting hormone action. Of particular concern are findings that developmental exposure to dioxins, chemicals that act through the aryl hydrocarbon receptor pathway, permanently alters sexually differentiated neural functions in animal models. In this review, we focus on mechanisms through which dioxins disrupt neuroendocrine development as exemplified by effects on a brain region critical for ovulation in rodents. We also provide evidence that dysregulation of GABAergic neural development may be a general mechanism underlying a broad spectrum of effects seen after perinatal dioxin exposure.
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Affiliation(s)
- Sandra L Petersen
- Department of Biology, University of Massachusetts-Amherst, Amherst, Massachusetts 01003 USA.
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Kim SH, Henry EC, Kim DK, Kim YH, Shin KJ, Han MS, Lee TG, Kang JK, Gasiewicz TA, Ryu SH, Suh PG. Novel compound 2-methyl-2H-pyrazole-3-carboxylic acid (2-methyl-4-o-tolylazo-phenyl)-amide (CH-223191) prevents 2,3,7,8-TCDD-induced toxicity by antagonizing the aryl hydrocarbon receptor. Mol Pharmacol 2006; 69:1871-8. [PMID: 16540597 DOI: 10.1124/mol.105.021832] [Citation(s) in RCA: 202] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a widespread environmental pollutant with many toxic effects, including endocrine disruption, reproductive dysfunction, immunotoxicity, liver damage, and cancer. These are mediated by TCDD binding to and activating the aryl hydrocarbon receptor (AhR), a basic helix-loop-helix transcription factor. In this regard, targeting the AhR using novel small molecule inhibitors is an attractive strategy for the development of potential preventive agents. In this study, by screening a chemical library composed of approximately 10,000 compounds, we identified a novel compound, 2-methyl-2H-pyrazole-3-carboxylic acid (2-methyl-4-o-tolylazo-phenyl)-amide (CH-223191), that potently inhibits TCDD-induced AhR-dependent transcription. In addition, CH-223191 blocked the binding of TCDD to AhR and inhibited TCDD-mediated nuclear translocation and DNA binding of AhR. These inhibitory effects of CH-223191 prevented the expression of cytochrome P450 enzymes, target genes of the AhR. Unlike many known antagonists of AhR, CH-223191 did not have detectable AhR agonist-like activity or estrogenic potency, suggesting that CH-223191 is a specific antagonist of AhR. It is noteworthy that CH-223191 potently prevented TCDD-elicited cytochrome P450 induction, liver toxicity, and wasting syndrome in mice. Taken together, these results demonstrate that this novel compound, CH-223191, may be a useful agent for the study of AhR-mediated signal transduction and the prevention of TCDD-associated pathology.
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Affiliation(s)
- Sun-Hee Kim
- School of Environmental Science and Engineering, Pohang University of Science and Technology, Pohang 790-784, South Korea
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Nishiumi S, Yabushita Y, Fukuda I, Mukai R, Yoshida KI, Ashida H. Molokhia (Corchorus olitorius L.) extract suppresses transformation of the aryl hydrocarbon receptor induced by dioxins. Food Chem Toxicol 2005; 44:250-60. [PMID: 16115717 DOI: 10.1016/j.fct.2005.07.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Revised: 07/01/2005] [Accepted: 07/11/2005] [Indexed: 11/21/2022]
Abstract
Dioxins enter the body mainly through diet and cause the various toxicological effects by binding to the cytosolic aryl hydrocarbon receptor (AhR) followed by its transformation. In recent reports, it has been shown that certain natural compounds suppress AhR transformation in vitro. In this study, we demonstrated that ethanolic extract from molokhia, known as Egyptian spinach, showed the strongest suppressive effect on AhR transformation induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in cell-free system using rat hepatic cytosol among 41 kinds of extracts from vegetables and fruits. The molokhia extract also suppressed TCDD-induced AhR transformation in mouse hepatoma Hepa-1c1c7 cells and in intestinal permeability system constructed with human colon adenocarcinoma Caco-2 cells and human hepatoma HepG2 cells. Moreover, oral administration of the molokhia extract (100mg/kg body weight) decreased 3-methylcholanthrene-induced AhR transformation to the control level by inhibiting translocation of the AhR from cytosol into the nucleus in the liver of rats. The molokhia extract-administered rat liver showed a tolerance to TCDD-induced AhR transformation by ex vivo experiment. These results indicate that molokhia is an attractive food for isolation and identification of a natural antagonist for the AhR.
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Affiliation(s)
- Shin Nishiumi
- Department of Biofunctional Chemistry, Faculty of Agriculture, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
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Tang C, Lin JH, Lu AYH. Metabolism-based drug-drug interactions: what determines individual variability in cytochrome P450 induction? Drug Metab Dispos 2005; 33:603-13. [PMID: 15673596 DOI: 10.1124/dmd.104.003236] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Individual variability in cytochrome P450 (P450) induction comprises an important component contributing to the difficulties in assessing and predicting metabolism-based drug-drug interactions in humans. In this article, we outline the major factors responsible for the individual variability in P450 induction, including variable transporter activity and metabolism of inducers in vivo, genetic variations of P450 genes and their regulatory regions, genetic variations of receptors and regulatory proteins required for induction, and different physiological and environmental elements. With a better understanding of the major determinants in P450 induction and a profile of the phenotypes of these determinants in each individual, it is believed that the individual variability in induction-mediated drug-drug interactions can be adequately evaluated.
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Affiliation(s)
- Cuyue Tang
- Department of Drug Metabolism, Merck Research Laboratories, Sumneytown Pike, West Point, PA 19486-0004, USA.
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