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Badawy AAB, Dawood S. Molecular Insights into the Interaction of Tryptophan Metabolites with the Human Aryl Hydrocarbon Receptor in Silico: Tryptophan as Antagonist and no Direct Involvement of Kynurenine. FRONT BIOSCI-LANDMRK 2024; 29:333. [PMID: 39344334 DOI: 10.31083/j.fbl2909333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2024] [Revised: 08/08/2024] [Accepted: 08/21/2024] [Indexed: 10/01/2024]
Abstract
BACKGROUND A direct link between the tryptophan (Trp) metabolite kynurenine (Kyn) and the aryl hydrocarbon receptor (AhR) is not supported by metabolic considerations and by studies demonstrating the failure of Kyn concentrations of up to 100 μM to activate the receptor in cell culture systems using the proxy system of cytochrome P-450-dependent metabolism. The Kyn metabolite kynurenic acid (KA) activates the AhR and may mediate the Kyn link. Recent studies demonstrated down regulation and antagonism of activation of the AhR by Trp. We have addressed the link between Kyn and the AhR by looking at their direct molecular interaction in silico. METHODS Molecular docking of Kyn, KA, Trp and a range of Trp metabolites to the crystal structure of the human AhR was performed under appropriate docking conditions. RESULTS Trp and 30 of its metabolites docked to the AhR to various degrees, whereas Kyn and 3-hydroxykynurenine did not. The strongest docking was observed with the Trp metabolite and photooxidation product 6-Formylindolo[3,2-b]carbazole (FICZ), cinnabarinic acid, 5-hydroxytryptophan, N-acetyl serotonin and indol-3-yllactic acid. Strong docking was also observed with other 5-hydroxyindoles. CONCLUSIONS We propose that the Kyn-AhR link is mediated by KA. The strong docking of Trp and its recently reported down regulation of the receptor suggest that Trp is an AhR antagonist and may thus play important roles in body homeostasis beyond known properties or simply being the precursor of biologically active metabolites. Differences in AhR activation reported in the literature are discussed.
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Affiliation(s)
- Abdulla A-B Badawy
- Formerly School of Health Sciences, Cardiff Metropolitan University, CF5 2YB Wales, UK
| | - Shazia Dawood
- Pharmacy and Allied Health Sciences, Iqra University, 7580 Karachi, Pakistan
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2
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Wen Z, Zhang Y, Zhang B, Hang Y, Xu L, Chen Y, Xie Q, Zhao Q, Zhang L, Li G, Zhao B, Sun F, Zhai Y, Zhu Y. Cryo-EM structure of the cytosolic AhR complex. Structure 2023; 31:295-308.e4. [PMID: 36649707 DOI: 10.1016/j.str.2022.12.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 11/24/2022] [Accepted: 12/21/2022] [Indexed: 01/17/2023]
Abstract
Aryl hydrocarbon receptor (AhR) is an important ligand-activated transcription factor involved in the regulation of various important physiological functions. Here, we report the cryo-EM structures of the Hsp90-AhR-p23 complex with or without bound XAP2, where the structure of the mouse AhR PAS-B domain is resolved. A highly conserved bridge motif of AhR is responsible for the interaction with the Hsp90 dimeric lumen. The ligand-free AhR PAS-B domain is attached to the Hsp90 dimer and is stabilized in the complex with bound XAP2. In addition, the DE-loop and a group of conserved pocket inner residues in the AhR PAS-B domain are found to be important for ligand binding. These results reveal the structural basis of the biological functions of AhR. Moreover, the protein purification method presented here allows the isolation of stable mouse AhR protein, which could be used to develop high-sensitivity biosensors for environmental pollutant detection.
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Affiliation(s)
- Zuoling Wen
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing, China
| | - Yuebin Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China
| | - Beirong Zhang
- University of Chinese Academy of Sciences, Beijing, China; CAS Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic R. & A. Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
| | - Yumo Hang
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Li Xu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yangsheng Chen
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Qunhui Xie
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Qun Zhao
- CAS Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic R. & A. Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
| | - Lihua Zhang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic R. & A. Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
| | - Guohui Li
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China
| | - Bin Zhao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Fei Sun
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing, China; Center for Biological Imaging, Core Facilities for Protein Science, Institute of Biophysics, CAS, Beijing, China.
| | - Yujia Zhai
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
| | - Yun Zhu
- National Key Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
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3
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Post CM, Myers JR, Winans B, Lawrence BP. Postnatal administration of S-adenosylmethionine restores developmental AHR activation-induced deficits in CD8+ T cell function during influenza A virus infection. Toxicol Sci 2023; 192:kfad019. [PMID: 36847456 PMCID: PMC10109536 DOI: 10.1093/toxsci/kfad019] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023] Open
Abstract
Developmental exposures can influence life-long health; yet, counteracting negative consequences is challenging due to poor understanding of cellular mechanisms. The aryl hydrocarbon receptor (AHR) binds many small molecules, including numerous pollutants. Developmental exposure to the signature environmental AHR ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) significantly dampens adaptive immune responses to influenza A virus (IAV) in adult offspring. CD8+ cytotoxic T lymphocytes (CTL) are crucial for successful infection resolution, which depends on the number generated and the complexity of their functionality. Prior studies showed developmental AHR activation significantly reduced the number of virus-specific CD8+ T cells, but impact on their functions is less clear. Other studies showed developmental exposure was associated with differences in DNA methylation in CD8+ T cells. Yet, empirical evidence that differences in DNA methylation are causally related to altered CD8+ T cell function is lacking. The two objectives were to ascertain whether developmental AHR activation affects CTL function, and whether differences in methylation contribute to reduced CD8+ T cell responses to infection. Developmental AHR triggering significantly reduced CTL polyfunctionality, and modified the transcriptional program of CD8+ T cells. S-adenosylmethionine (SAM), which increases DNA methylation, but not Zebularine, which diminishes DNA methylation, restored polyfunctionality and boosted the number of virus-specific CD8+ T cells. These findings suggest that diminished methylation, initiated by developmental exposure to an AHR-binding chemical, contributes to durable changes in antiviral CD8+ CTL functions later in life. Thus, deleterious consequence of development exposure to environmental chemicals are not permanently fixed, opening the door for interventional strategies to improve health.
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Affiliation(s)
- Christina M Post
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Jason R Myers
- Genomics Research Center, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Bethany Winans
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - B Paige Lawrence
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
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4
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Abudahab S, Price ET, Dozmorov MG, Deshpande LS, McClay JL. The Aryl Hydrocarbon Receptor, Epigenetics and the Aging Process. J Nutr Health Aging 2023; 27:291-300. [PMID: 37170437 PMCID: PMC10947811 DOI: 10.1007/s12603-023-1908-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor, classically associated with the regulation of xenobiotic metabolism in response to environmental toxins. In recent years, transgenic rodent models have implicated AhR in aging and longevity. Moreover, several AhR ligands, such as resveratrol and quercetin, are compounds proven to extend the lifespan of model organisms. In this paper, we first review AhR biology with a focus on aging and highlight several AhR ligands with potential anti-aging properties. We outline how AhR-driven expression of xenobiotic metabolism genes into old age may be a key mechanism through which moderate induction of AhR elicits positive benefits on longevity and healthspan. Furthermore, via integration of publicly available datasets, we show that liver-specific AhR target genes are enriched among genes subject to epigenetic aging. Changes to epigenetic states can profoundly affect transcription factor binding and are a hallmark of the aging process. We suggest that the interplay between AhR and epigenetic aging should be the subject of future research and outline several key gaps in the current literature. Finally, we recommend that a broad range of non-toxic AhR ligands should be investigated for their potential to promote healthspan and longevity.
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Affiliation(s)
- S Abudahab
- Sara Abudahab, Smith Building, 410 North 12th Street, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, VA 23298-0533, USA.
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5
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Dai S, Qu L, Li J, Zhang Y, Jiang L, Wei H, Guo M, Chen X, Chen Y. Structural insight into the ligand binding mechanism of aryl hydrocarbon receptor. Nat Commun 2022; 13:6234. [PMID: 36266304 PMCID: PMC9585082 DOI: 10.1038/s41467-022-33858-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 10/04/2022] [Indexed: 12/25/2022] Open
Abstract
The aryl hydrocarbon receptor (AHR), a member of the basic helix-loop-helix (bHLH) Per-Arnt-Sim (PAS) family of transcription factors, plays important roles in regulating xenobiotic metabolism, cellular differentiation, stem cell maintenance, as well as immunity. More recently, AHR has gained significant interest as a drug target for the development of novel cancer immunotherapy drugs. Detailed understanding of AHR-ligand binding has been hampered for decades by the lack of a three-dimensional structure of the AHR PAS-B domain. Here, we present multiple crystal structures of the Drosophila AHR PAS-B domain, including its apo, ligand-bound, and AHR nuclear translocator (ARNT) PAS-B-bound forms. Together with biochemical and cellular assays, our data reveal structural features of the AHR PAS-B domain, provide insights into the mechanism of AHR ligand binding, and provide the structural basis for the future development of AHR-targeted therapeutics.
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Affiliation(s)
- Shuyan Dai
- grid.216417.70000 0001 0379 7164Department of Oncology, NHC Key Laboratory of Cancer Proteomics & State Local Joint Engineering Laboratory for Anticancer Drugs, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008 China
| | - Lingzhi Qu
- grid.216417.70000 0001 0379 7164Department of Oncology, NHC Key Laboratory of Cancer Proteomics & State Local Joint Engineering Laboratory for Anticancer Drugs, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008 China
| | - Jun Li
- grid.461579.8Institute of Clinical Medicine, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001 China
| | - Ye Zhang
- grid.216417.70000 0001 0379 7164Department of Oncology, NHC Key Laboratory of Cancer Proteomics & State Local Joint Engineering Laboratory for Anticancer Drugs, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008 China
| | - Longying Jiang
- grid.216417.70000 0001 0379 7164Department of Oncology, NHC Key Laboratory of Cancer Proteomics & State Local Joint Engineering Laboratory for Anticancer Drugs, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008 China
| | - Hudie Wei
- grid.216417.70000 0001 0379 7164Department of Oncology, NHC Key Laboratory of Cancer Proteomics & State Local Joint Engineering Laboratory for Anticancer Drugs, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008 China
| | - Ming Guo
- grid.216417.70000 0001 0379 7164Department of Oncology, NHC Key Laboratory of Cancer Proteomics & State Local Joint Engineering Laboratory for Anticancer Drugs, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008 China
| | - Xiaojuan Chen
- grid.216417.70000 0001 0379 7164Department of Oncology, NHC Key Laboratory of Cancer Proteomics & State Local Joint Engineering Laboratory for Anticancer Drugs, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008 China
| | - Yongheng Chen
- grid.216417.70000 0001 0379 7164Department of Oncology, NHC Key Laboratory of Cancer Proteomics & State Local Joint Engineering Laboratory for Anticancer Drugs, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008 China
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6
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Salminen A. Aryl hydrocarbon receptor (AhR) reveals evidence of antagonistic pleiotropy in the regulation of the aging process. Cell Mol Life Sci 2022; 79:489. [PMID: 35987825 PMCID: PMC9392714 DOI: 10.1007/s00018-022-04520-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 07/14/2022] [Accepted: 08/08/2022] [Indexed: 11/24/2022]
Abstract
The antagonistic pleiotropy hypothesis is a well-known evolutionary theory to explain the aging process. It proposes that while a particular gene may possess beneficial effects during development, it can exert deleterious properties in the aging process. The aryl hydrocarbon receptor (AhR) has a significant role during embryogenesis, but later in life, it promotes several age-related degenerative processes. For instance, AhR factor (i) controls the pluripotency of stem cells and the stemness of cancer stem cells, (ii) it enhances the differentiation of embryonal stem cells, especially AhR signaling modulates the differentiation of hematopoietic stem cells and progenitor cells, (iii) it also stimulates the differentiation of immunosuppressive Tregs, Bregs, and M2 macrophages, and finally, (iv) AhR signaling participates in the differentiation of many peripheral tissues. On the other hand, AhR signaling is involved in many processes promoting cellular senescence and pathological processes, e.g., osteoporosis, vascular dysfunction, and the age-related remodeling of the immune system. Moreover, it inhibits autophagy and aggravates extracellular matrix degeneration. AhR signaling also stimulates oxidative stress, promotes excessive sphingolipid synthesis, and disturbs energy metabolism by catabolizing NAD+ degradation. The antagonistic pleiotropy of AhR signaling is based on the complex and diverse connections with major signaling pathways in a context-dependent manner. The major regulatory steps include, (i) a specific ligand-dependent activation, (ii) modulation of both genetic and non-genetic responses, (iii) a competition and crosstalk with several transcription factors, such as ARNT, HIF-1α, E2F1, and NF-κB, and (iv) the epigenetic regulation of target genes with binding partners. Thus, not only mTOR signaling but also the AhR factor demonstrates antagonistic pleiotropy in the regulation of the aging process.
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Affiliation(s)
- Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland.
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7
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Dai R, Huang C, Wu X, Ma X, Chu M, Bao P, Pei J, Guo X, Yan P, Liang C. Copy number variation (CNV) of the AHR gene in the Ashidan yak and its association with growth traits. Gene 2022; 826:146454. [PMID: 35367304 DOI: 10.1016/j.gene.2022.146454] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 02/24/2022] [Accepted: 03/18/2022] [Indexed: 01/03/2023]
Abstract
Copy number variation (CNV) is a principal genomic structure variation affecting the gene expression through the dose-effect and change of gene regulatory region. It plays an important role in regulating the various complex traits of vertebrates. The aromatic hydrocarbon receptor (AHR) is a member of ligand-dependent transcription factors which belong to the alkaline helix-loop-helix PASS family. It is used as a conservative environmental sensor during biological evolution. This study, tracked the growth data (body weight, withers height, body length, chest girth) of 332 yaks in four stages (6, 12, 18, and 30 months) were tracked. The CNV of the yaks was analyzed using real-time quantitative PCR, and the correlation between CNV of AHR and yak growth traits was analyzed using the SPSS and R software. The AHR gene expression profiles were assessed in different tissues of the 18-month-old yak. The statistical analysis indicated the AHR-CNV of the Ashidan yak to significantly correlate with the body length (P < 0.05), and was found to be correlated with the withers height at 18 months old (P < 0.01) with extreme significance. To sum up, this study for the first time discussed the relationship between AHR-CNV and the growth traits of the Ashidan yak. The results indicated that the AHR gene might become a new molecular marker in the breeding yak.
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Affiliation(s)
- Rongfeng Dai
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Chun Huang
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xiaoyun Wu
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xiaoming Ma
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Min Chu
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Pengjia Bao
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Jie Pei
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xian Guo
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Ping Yan
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China.
| | - Chunnian Liang
- Key Laboratory of Yak Breeding Engineering Gansu Province, Lanzhou Institute of Husbandry and Pharmaceutical Science, Chinese Academy of Agricultural Sciences, Lanzhou, China.
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Current Therapeutic Landscape and Safety Roadmap for Targeting the Aryl Hydrocarbon Receptor in Inflammatory Gastrointestinal Indications. Cells 2022; 11:cells11101708. [PMID: 35626744 PMCID: PMC9139855 DOI: 10.3390/cells11101708] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/30/2022] [Accepted: 05/16/2022] [Indexed: 02/07/2023] Open
Abstract
Target modulation of the AhR for inflammatory gastrointestinal (GI) conditions holds great promise but also the potential for safety liabilities both within and beyond the GI tract. The ubiquitous expression of the AhR across mammalian tissues coupled with its role in diverse signaling pathways makes development of a “clean” AhR therapeutically challenging. Ligand promiscuity and diversity in context-specific AhR activation further complicates targeting the AhR for drug development due to limitations surrounding clinical translatability. Despite these concerns, several approaches to target the AhR have been explored such as small molecules, microbials, PROTACs, and oligonucleotide-based approaches. These various chemical modalities are not without safety liabilities and require unique de-risking strategies to parse out toxicities. Collectively, these programs can benefit from in silico and in vitro methodologies that investigate specific AhR pathway activation and have the potential to implement thresholding parameters to categorize AhR ligands as “high” or “low” risk for sustained AhR activation. Exploration into transcriptomic signatures for AhR safety assessment, incorporation of physiologically-relevant in vitro model systems, and investigation into chronic activation of the AhR by structurally diverse ligands will help address gaps in our understanding regarding AhR-dependent toxicities. Here, we review the role of the AhR within the GI tract, novel therapeutic modality approaches to target the AhR, key AhR-dependent safety liabilities, and relevant strategies that can be implemented to address drug safety concerns. Together, this review discusses the emerging therapeutic landscape of modalities targeting the AhR for inflammatory GI indications and offers a safety roadmap for AhR drug development.
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Defining the AHR-regulated transcriptome in NK cells reveals gene expression programs relevant to development and function. Blood Adv 2021; 5:4605-4618. [PMID: 34559190 PMCID: PMC8759121 DOI: 10.1182/bloodadvances.2021004533] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 07/27/2021] [Indexed: 12/20/2022] Open
Abstract
AHR directly regulates a wide range of genes in NK cells, including those involved in cell signaling, oxidative stress, and metabolism. Knowing of the repertoire of genes regulated by AHR may help us better understand NK-cell dysfunction mediated by AHR ligands in cancer.
The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that regulates cellular processes in cancer and immunity, including innate immune cell development and effector function. However, the transcriptional repertoire through which AHR mediates these effects remains largely unexplored. To elucidate the transcriptional elements directly regulated by AHR in natural killer (NK) cells, we performed RNA and chromatin immunoprecipitation sequencing on NK cells exposed to AHR agonist or antagonist. We show that mature peripheral blood NK cells lack AHR, but its expression is induced by Stat3 during interleukin-21–driven activation and proliferation, coincident with increased NCAM1 (CD56) expression resulting in a CD56bright phenotype. Compared with control conditions, NK cells expanded in the presence of the AHR antagonist, StemRegenin-1, were unaffected in proliferation or cytotoxicity, had no increase in NCAM1 transcription, and maintained the CD56dim phenotype. However, it showed altered expression of 1004 genes including those strongly associated with signaling pathways. In contrast, NK cells expanded in the presence of the AHR agonist, kynurenine, showed decreased cytotoxicity and altered expression of 97 genes including those strongly associated with oxidative stress and cellular metabolism. By overlaying these differentially expressed genes with AHR chromatin binding, we identified 160 genes directly regulated by AHR, including hallmark AHR targets AHRR and CYP1B1 and known regulators of phenotype, development, metabolism, and function such as NCAM1, KIT, NQO1, and TXN. In summary, we define the AHR transcriptome in NK cells, propose a model of AHR and Stat3 coregulation, and identify potential pathways that may be targeted to overcome AHR-mediated immune suppression.
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Disner GR, Lopes-Ferreira M, Lima C. Where the Aryl Hydrocarbon Receptor Meets the microRNAs: Literature Review of the Last 10 Years. Front Mol Biosci 2021; 8:725044. [PMID: 34746229 PMCID: PMC8566438 DOI: 10.3389/fmolb.2021.725044] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 09/14/2021] [Indexed: 12/18/2022] Open
Abstract
The aryl hydrocarbon receptor (AhR) is an environmentally responsive ligand-activated transcription factor, identified in the ‘70s for its toxic responses to halogenated polycyclic aromatic hydrocarbons, such as dioxin. Recently, AhR has been recognized as engaged in multiple physiological processes in health and diseases, particularly in the immune system, inflammatory response, tumorigenesis, and cellular differentiation by epigenetic mechanisms involving miRNAs. However, there is still scarce information about AhR-dependent miRNA regulation and miRNA-mediated epigenetic control in pathologies and therapies. In this review, we explore the mutual regulation of AhR and miRNA over the last decade of studies since many miRNAs have dioxin response elements (DRE) in their 3’ UTR, as well as AhR might contain binding sites of miRNAs. TCDD is the most used ligand to investigate the impact of AhR activation, and the immune system is one of the most sensitive of its targets. An association between TCDD-activated AhR and epigenetic mechanisms like post-transcriptional regulation by miRNAs, DNA methylation, or histone modification has already been confirmed. Besides, several studies have shown that AhR-induced miR-212/132 cluster suppresses cancers, attenuates autoimmune diseases, and has an anti-inflammatory role in different immune responses by regulating cytokine levels and immune cells. Together the ever-expanding new AhR roles and the miRNA therapeutics are a prominent segment among biopharmaceuticals. Additionally, AhR-activated miRNAs can serve as valuable biomarkers of diseases, notably cancer progression or suppression and chemical exposure. Once AhR-dependent gene expression may hinge on the ligand, cell type, and context singularity, the reviewed outcomes might help contextualize state of the art and support new trends and emerging opportunities in the field.
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Affiliation(s)
- Geonildo Rodrigo Disner
- Immunoregulation Unit of the Laboratory of Applied Toxinology (CeTICS/FAPESP), Butantan Institute, São Paulo, Brazil
| | - Monica Lopes-Ferreira
- Immunoregulation Unit of the Laboratory of Applied Toxinology (CeTICS/FAPESP), Butantan Institute, São Paulo, Brazil
| | - Carla Lima
- Immunoregulation Unit of the Laboratory of Applied Toxinology (CeTICS/FAPESP), Butantan Institute, São Paulo, Brazil
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Han H, Safe S, Jayaraman A, Chapkin RS. Diet-Host-Microbiota Interactions Shape Aryl Hydrocarbon Receptor Ligand Production to Modulate Intestinal Homeostasis. Annu Rev Nutr 2021; 41:455-478. [PMID: 34633858 PMCID: PMC8667662 DOI: 10.1146/annurev-nutr-043020-090050] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated basic-helix-loop-helix transcription factor that binds structurally diverse ligands and senses cues from environmental toxicants and physiologically relevant dietary/microbiota-derived ligands. The AhR is an ancient conserved protein and is widely expressed across different tissues in vertebrates and invertebrates. AhR signaling mediates a wide range of cellular functions in a ligand-, cell type-, species-, and context-specific manner. Dysregulation of AhR signaling is linked to many developmental defects and chronic diseases. In this review, we discuss the emerging role of AhR signaling in mediating bidirectional host-microbiome interactions. We also consider evidence showing the potential for the dietary/microbial enhancement ofhealth-promoting AhR ligands to improve clinical pathway management in the context of inflammatory bowel diseases and colon tumorigenesis.
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Affiliation(s)
- Huajun Han
- Program in Integrative Nutrition and Complex Diseases and Department of Nutrition, Texas A&M University, College Station, Texas 77843, USA;
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas 77843, USA
| | - Stephen Safe
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas 77843, USA
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, Texas 77843, USA
| | - Arul Jayaraman
- Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, USA
| | - Robert S Chapkin
- Program in Integrative Nutrition and Complex Diseases and Department of Nutrition, Texas A&M University, College Station, Texas 77843, USA;
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, Texas 77843, USA
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12
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Vaughan KL, Franchini AM, Kern HG, Lawrence BP. The Aryl Hydrocarbon Receptor Modulates Murine Hematopoietic Stem Cell Homeostasis and Influences Lineage-Biased Stem and Progenitor Cells. Stem Cells Dev 2021; 30:970-980. [PMID: 34428990 PMCID: PMC8851211 DOI: 10.1089/scd.2021.0096] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 08/09/2021] [Indexed: 12/24/2022] Open
Abstract
The core function of hematopoietic stem and progenitor cells (HSPCs) is to provide lifelong production of all lineages of the blood and immune cells. The mechanisms that modulate HSPC homeostasis and lineage biasing are not fully understood. Growing evidence implicates the aryl hydrocarbon receptor (AHR), an environment-sensing transcription factor, as a regulator of hematopoiesis. AHR ligands modulate the frequency of mature hematopoietic cells in the bone marrow and periphery, while HSPCs from mice lacking AHR (AHR KO) have increased proliferation. Yet, whether AHR modulates HSPC lineage potential and directs differentiation toward specific lineage-biased progenitors is not well understood. This study revealed that AHR KO mice have an increased proportion of myeloid-biased HSCs and myeloid-biased multipotent progenitor (MPP3) cells. Utilizing inducible AHR knockout mice (iAHR KO), it was discovered that acute deletion of AHR doubled the number of MPP3 cells and altered the composition of downstream lineage-committed progenitors, such as increased frequency of pregranulocyte/premonocyte committed progenitors. Furthermore, in vivo antagonism of the AHR led to a 2.5-fold increase in the number of MPP3 cells and promoted myeloid-biased differentiation. Using hematopoietic-specific conditional AHR knockout mice (AHRVav1) revealed that increased frequency of myeloid-biased HSCs and myeloid-biased progenitors is driven by AHR signaling that is intrinsic to the hematopoietic compartment. These findings demonstrate that the AHR plays a pivotal role in regulating steady-state hematopoiesis, influencing HSPC homeostasis and lineage potential. In addition, the data presented provide potential insight into how deliberate modulation of AHR signaling could help with the treatment of a broad range of diseases that require the hematopoietic compartment.
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Affiliation(s)
- Keegan L. Vaughan
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Anthony M. Franchini
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Harrison G. Kern
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - B. Paige Lawrence
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
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13
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Bock KW. Aryl hydrocarbon receptor (AHR) functions in infectious and sterile inflammation and NAD +-dependent metabolic adaptation. Arch Toxicol 2021; 95:3449-3458. [PMID: 34559251 PMCID: PMC8461142 DOI: 10.1007/s00204-021-03134-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 08/11/2021] [Indexed: 01/13/2023]
Abstract
Aryl hydrocarbon receptor (AHR) research has shifted from exploring dioxin toxicity to elucidation of various physiologic AHR functions. Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is known to exert cellular stress-mediated sterile inflammatory responses in exposed human tissues but may be lethal in sensitive species. Inflammation can be thought of as the extreme end of a spectrum ranging from homeostasis to stress responses (sterile inflammation) and to defense against infection (infectious inflammation). Defense against bacterial infection by generation of reactive oxygen species has to be strictly controlled and may use up a considerable amount of energy. NAD+-mediated energy metabolism adapts to various inflammatory responses. As examples, the present commentary tries to integrate responses of AHR and NAD+-consuming enzymes (PARP7/TiPARP, CD38 and sirtuins) into infectious and stress-induced inflammatory responses, the latter exemplified by nonalcoholic fatty liver disease (NAFLD). TCDD toxicity models in sensitive species provide hints to molecular AHR targets of energy metabolism including gluconeogenesis and glycolysis. AHR research remains challenging and promising.
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Affiliation(s)
- Karl Walter Bock
- Institute of Experimental and Clinical Pharmacology and Toxicology, Wilhelmstrasse 56, 72074, Tübingen, Germany.
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14
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Liberatori G, Cotugno P, Sturba L, Vannuccini ML, Capasso G, Velardo R, Besselink H, Massari F, Tursi A, Corbelli V, Behnisch PA, Corsi I. Occurrence and spatial distribution of dioxin and dioxin-like compounds in topsoil of Taranto (Apulia, Italy) by GC-MS analysis and DR-CALUX® bioassay. CHEMOSPHERE 2021; 279:130576. [PMID: 33894519 DOI: 10.1016/j.chemosphere.2021.130576] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 04/02/2021] [Accepted: 04/09/2021] [Indexed: 06/12/2023]
Abstract
The aim of the present study was to assess the occurrence and spatial distribution of PCDD/Fs and dioxin-like compounds in topsoils of Taranto (Apulia Region), one of the most heavily industrialized and contaminated area of Southern Italy. A combined approach of chemical analysis by GC-MS/MS and AhR reporter gene bioassay was applied in a subset of topsoil samples (n = 20) collected in 2017-18 from ten sites embracing three levels of risk (from high to low) in the framework of a large survey inside Taranto municipality. TCDD-BEQs and GC-MS/MS TEQWHO and TEQTHEORETICAL revealed a decreasing trend with the distance from main industrial settings and landfill areas. A strong correlation between TCDD-BEQs and TEQWHO values (R2 = 0.85) and TEQTHEORETICAL (R2 = 0.88) was also found. In 3 out of 10 topsoil investigated, BEQs and TEQWHO/THEORETICAL resulted above Italian National Regulatory Limits for ∑PCDD/Fs in green, private and recreational used soils (10 ng TEQ/kg d.w. D.Lgs 152/2006) and for ∑PCDD/F/dl-PCBs in agricultural and farming soil (6 ng TEQ/kg d.w. D.M. 46/2019). GC-MS/MS pattern revealed the highest prevalence of dl-PCBs in 6 out of 10 sites, followed by PCDFs and PCDDs. Those sites are all located in proximity of main industrial steel and iron ore sinter plant, steel plant's landfills and illegal dumping sites. An update on occurrence and spatial distribution of PCDD/Fs and dl-PCBs contamination of Taranto urban soils was obtained and the DR-CALUX® bioassay was further recommended as a suitable screening tool for environmental and human risk assessment.
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Affiliation(s)
- Giulia Liberatori
- Department of Physical, Earth and Environmental Sciences, University of Siena, Siena, Italy.
| | - Pietro Cotugno
- Department of Biology, University of Bari Aldo Moro, Bari, Italy
| | - Lucrezia Sturba
- Department of Physical, Earth and Environmental Sciences, University of Siena, Siena, Italy
| | - Maria Luisa Vannuccini
- Department of Physical, Earth and Environmental Sciences, University of Siena, Siena, Italy
| | - Gennaro Capasso
- Special Commissioner for Urgent Intervention for Remediation, Environmental Enhancement and Upgrading of Taranto, Taranto, Italy
| | - Raffaele Velardo
- Special Commissioner for Urgent Intervention for Remediation, Environmental Enhancement and Upgrading of Taranto, Taranto, Italy
| | | | - Federica Massari
- Department of Biology, University of Bari Aldo Moro, Bari, Italy
| | - Angelo Tursi
- Department of Biology, University of Bari Aldo Moro, Bari, Italy
| | - Vera Corbelli
- Special Commissioner for Urgent Intervention for Remediation, Environmental Enhancement and Upgrading of Taranto, Taranto, Italy
| | | | - Ilaria Corsi
- Department of Physical, Earth and Environmental Sciences, University of Siena, Siena, Italy
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15
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Gargaro M, Manni G, Scalisi G, Puccetti P, Fallarino F. Tryptophan Metabolites at the Crossroad of Immune-Cell Interaction via the Aryl Hydrocarbon Receptor: Implications for Tumor Immunotherapy. Int J Mol Sci 2021; 22:ijms22094644. [PMID: 33924971 PMCID: PMC8125364 DOI: 10.3390/ijms22094644] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/25/2021] [Accepted: 04/25/2021] [Indexed: 02/07/2023] Open
Abstract
The Aryl hydrocarbon receptor (AhR) is a critical regulator of both innate and adaptive immune responses, with potent immunomodulatory effects that makes this receptor an attractive molecular target for novel therapeutics. Accumulating evidence indicates that diverse—both host’s and microbial—tryptophan metabolites profoundly regulate the immune system in the host via AhR, promoting either tolerance or immunity, largely as a function of the qualitative and quantitative nature of the metabolites being contributed by either source. Additional findings indicate that host and microbiota-derived tryptophan metabolic pathways can influence the outcome of immune responses to tumors. Here, we review recent studies on the role and modalities of AhR activation by various ligands, derived from either host-cell or microbial-cell tryptophan metabolic pathways, in the regulation of immune responses. Moreover, we highlight potential implications of those ligands and pathways in tumor immunotherapy, with particular relevance to checkpoint-blockade immune intervention strategies.
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16
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Großkopf H, Walter K, Karkossa I, von Bergen M, Schubert K. Non-Genomic AhR-Signaling Modulates the Immune Response in Endotoxin-Activated Macrophages After Activation by the Environmental Stressor BaP. Front Immunol 2021; 12:620270. [PMID: 33868237 PMCID: PMC8045971 DOI: 10.3389/fimmu.2021.620270] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 03/15/2021] [Indexed: 12/16/2022] Open
Abstract
Emerging studies revealed that the Aryl hydrocarbon receptor (AhR), a receptor sensing environmental contaminants, is executing an immunomodulatory function. However, it is an open question to which extent this is achieved by its role as a transcription factor or via non-genomic signaling. We utilized a multi-post-translational modification-omics approach to examine non-genomic AhR-signaling after activation with endogenous (FICZ) or exogenous (BaP) ligand in endotoxin-activated (LPS) monocyte-derived macrophages. While AhR activation affected abundances of few proteins, regulation of ubiquitination and phosphorylation were highly pronounced. Although the number and strength of effects depended on the applied AhR-ligand, both ligands increased ubiquitination of Rac1, which participates in PI3K/AKT-pathway-dependent macrophage activation, resulting in a pro-inflammatory phenotype. In contrast, co-treatment with ligand and LPS revealed a decreased AKT activity mediating an anti-inflammatory effect. Thus, our data show an immunomodulatory effect of AhR activation through a Rac1ubiquitination-dependent mechanism that attenuated AKT-signaling, resulting in a mitigated inflammatory response.
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Affiliation(s)
- Henning Großkopf
- Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Katharina Walter
- Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Isabel Karkossa
- Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Martin von Bergen
- Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research, Leipzig, Germany.,Institute of Biochemistry, Leipzig University, Leipzig, Germany
| | - Kristin Schubert
- Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research, Leipzig, Germany
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17
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Zhu X, Sun Q, Tan WS, Cai H. Reducing TGF-β1 cooperated with StemRegenin 1 promoted the expansion ex vivo of cord blood CD34 + cells by inhibiting AhR signalling. Cell Prolif 2021; 54:e12999. [PMID: 33522060 PMCID: PMC7941221 DOI: 10.1111/cpr.12999] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 12/13/2020] [Accepted: 01/12/2021] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVE As an inhibitor of the AhR signalling pathway, StemRegenin 1 (SR1) not only promotes the expansion of CD34+ cells but also increases CD34- cell numbers. These CD34- cells influenced the ex vivo expansion of CD34+ cells. In this work, the effects of periodically removing CD34- cells combined with SR1 addition on the ex vivo expansion and biological functions of HSCs were investigated. MATERIALS AND METHODS CD34- cells were removed periodically with SR1 addition to investigate cell subpopulations, cell expansion, biological functions, expanded cell division mode and supernatant TGF-β1 contents. RESULTS After 10-day culture, the expansion of CD34+ cells in the CD34- cell removal plus SR1 group was significantly higher than that in the control group and the SR1 group. Moreover, periodically removing CD34- cells with SR1 addition improved the biological function of expanded CD34+ cells and significantly increased the percentage of self-renewal symmetric division of CD34+ cells. In addition, the concentration of total TGF-β1 and activated TGF-β1 in the supernatant was significantly lower than those in the control group and the SR1 group. RT-qPCR results showed that the periodic removal of CD34- cells with cooperation from SR1 further reduced the expression of AhR-related genes. CONCLUSIONS Periodic removal of CD34- cells plus cooperation with SR1 improved the expansion of CD34+ cells, maintained better biological function of expanded CD34+ cells and reduced the TGF-β1 contents by downregulating AhR signalling.
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Affiliation(s)
- Xuejun Zhu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Qihao Sun
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Wen-Song Tan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Haibo Cai
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
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18
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Wang F, Liang S, Hu J, Xu Y. Aryl hydrocarbon receptor connects dysregulated immune cells to atherosclerosis. Immunol Lett 2020; 228:55-63. [PMID: 33053378 DOI: 10.1016/j.imlet.2020.10.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/29/2020] [Accepted: 10/08/2020] [Indexed: 11/20/2022]
Abstract
As a chronic inflammatory disease with autoimmune components, atherosclerosis is the major cause of cardiovascular morbidity and mortality. Recent studies have revealed that the development of atherosclerosis is strongly linked to the functional activities of aryl hydrocarbon receptor (AHR), a chemical sensor that is also important for the development, maintenance, and function of a variety of immune cells. In this review, we focus on the impact of AHR signaling on the different cell types that are closely related to the atherogenesis, including T cells, B cells, dendritic cells, macrophages, foam cells, and hematopoietic stem cells in the arterial walls, and summarize the latest development on the interplay between this environmental sensor and immune cells in the context of atherosclerosis. Hopefully, elucidation of the role of AHR in atherosclerosis will facilitate the understanding of case variation in disease prevalence and may aid in the development of novel therapies.
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Affiliation(s)
- Fengge Wang
- Anhui Provincial Key Laboratory for Conservation and Exploitation of Biological Resources, School of Life Science, Anhui Normal University, Wuhu, 241000, China
| | - Shuangchao Liang
- Department of Vascular Surgery, Yijishan Hospital of Wannan Medical College, Wuhu, 241000, China
| | - Jiqiong Hu
- Department of Vascular Surgery, Yijishan Hospital of Wannan Medical College, Wuhu, 241000, China
| | - Yuekang Xu
- Anhui Provincial Key Laboratory for Conservation and Exploitation of Biological Resources, School of Life Science, Anhui Normal University, Wuhu, 241000, China.
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19
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Xing PY, Pettersson S, Kundu P. Microbial Metabolites and Intestinal Stem Cells Tune Intestinal Homeostasis. Proteomics 2020; 20:e1800419. [PMID: 31994831 DOI: 10.1002/pmic.201800419] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 01/07/2020] [Indexed: 12/13/2022]
Abstract
Microorganisms that colonize the gastrointestinal tract, collectively known as the gut microbiota, are known to produce small molecules and metabolites that significantly contribute to host intestinal development, functions, and homeostasis. Emerging insights from microbiome research reveal that gut microbiota-derived signals and molecules influence another key player maintaining intestinal homeostasis-the intestinal stem cell niche, which regulates epithelial self-renewal. In this review, the literature on gut microbiota-host crosstalk is surveyed, highlighting the effects of gut microbial metabolites on intestinal stem cells. The production of various classes of metabolites, their actions on intestinal stem cells are discussed and, finally, how the production and function of metabolites are modulated by aging and dietary intake is commented upon.
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Affiliation(s)
- Peter Yuli Xing
- Singapore Centre for Environmental Life Sciences Engineering, 60 Nanyang Drive, Singapore, 637551, Singapore.,Interdisciplinary Graduate School, Nanyang Technological University, 50 Nanyang Avenue, South Spine, Level B3, Block S2-B3a, Singapore, 639798, Singapore
| | - Sven Pettersson
- Singapore Centre for Environmental Life Sciences Engineering, 60 Nanyang Drive, Singapore, 637551, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Singapore, 308232, Singapore.,Department of Neurobiology, Care Sciences and Society, Karolinska Institute, SE, 17 177, Stockholm, Sweden
| | - Parag Kundu
- Singapore Centre for Environmental Life Sciences Engineering, 60 Nanyang Drive, Singapore, 637551, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Singapore, 308232, Singapore.,The Center for Microbes, Development and Health, Laboratory for Microbiota-Host Interactions, Institute Pasteur of Shanghai, Chinese Academy of Sciences, 320 Yueyang Road, Life Science Research Building, Shanghai, 200031, China
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20
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Trikha P, Lee DA. The role of AhR in transcriptional regulation of immune cell development and function. Biochim Biophys Acta Rev Cancer 2019; 1873:188335. [PMID: 31816350 DOI: 10.1016/j.bbcan.2019.188335] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 12/02/2019] [Accepted: 12/02/2019] [Indexed: 12/13/2022]
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcriptional factor (TF) that is a member of the Per-Arnt-Sim family of proteins. AhR regulates diverse processes, including malignant transformation, hematopoietic cell development, and fate determination of immune cell lineages. Moreover, AhR forms a crucial link between innate and adaptive arms of the immune system. Malignant cells frequently evolve multiple mechanisms for suppressing tumor-specific responses, including the induction of suppressive pathways involving AhR and its metabolic byproducts in the tumor microenvironment that promote immune evasion and tumor progression. Thus, interest is high in further defining the role of AhR in carcinogenesis and immune development and regulation, particularly regarding the therapeutic interventions that unleash immune responses to cancer cells. Here, we provide an overview of the role of AhR in the regulation of innate and adaptive immune response and discuss the implications of targeting this pathway to augment the immune response in cancer patients.
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Affiliation(s)
- Prashant Trikha
- Cellular Therapy & Cancer Immunotherapy Program, Center for Childhood Cancer & Blood Diseases, WA-4112 Abigail Wexner Research Institute, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, United States of America.
| | - Dean A Lee
- Cellular Therapy & Cancer Immunotherapy Program, Center for Childhood Cancer & Blood Diseases, WA-4112 Abigail Wexner Research Institute, Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, United States of America
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21
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Aryl hydrocarbon receptor is indispensable for β-naphthoflavone-induced novel food avoidance and may be involved in LiCl-triggered conditioned taste aversion in rats. Physiol Behav 2019; 204:58-64. [DOI: 10.1016/j.physbeh.2019.02.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/18/2019] [Accepted: 02/11/2019] [Indexed: 12/31/2022]
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22
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Gérard D, Schmidt F, Ginolhac A, Schmitz M, Halder R, Ebert P, Schulz MH, Sauter T, Sinkkonen L. Temporal enhancer profiling of parallel lineages identifies AHR and GLIS1 as regulators of mesenchymal multipotency. Nucleic Acids Res 2019; 47:1141-1163. [PMID: 30544251 PMCID: PMC6380961 DOI: 10.1093/nar/gky1240] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 11/23/2018] [Accepted: 12/03/2018] [Indexed: 01/04/2023] Open
Abstract
Temporal data on gene expression and context-specific open chromatin states can improve identification of key transcription factors (TFs) and the gene regulatory networks (GRNs) controlling cellular differentiation. However, their integration remains challenging. Here, we delineate a general approach for data-driven and unbiased identification of key TFs and dynamic GRNs, called EPIC-DREM. We generated time-series transcriptomic and epigenomic profiles during differentiation of mouse multipotent bone marrow stromal cell line (ST2) toward adipocytes and osteoblasts. Using our novel approach we constructed time-resolved GRNs for both lineages and identifed the shared TFs involved in both differentiation processes. To take an alternative approach to prioritize the identified shared regulators, we mapped dynamic super-enhancers in both lineages and associated them to target genes with correlated expression profiles. The combination of the two approaches identified aryl hydrocarbon receptor (AHR) and Glis family zinc finger 1 (GLIS1) as mesenchymal key TFs controlled by dynamic cell type-specific super-enhancers that become repressed in both lineages. AHR and GLIS1 control differentiation-induced genes and their overexpression can inhibit the lineage commitment of the multipotent bone marrow-derived ST2 cells.
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Affiliation(s)
- Deborah Gérard
- Life Sciences Research Unit, University of Luxembourg, L-4367 Belvaux, Luxembourg
| | - Florian Schmidt
- Excellence Cluster for Multimodal Computing and Interaction, Saarland Informatics Campus, 66123 Saarbrücken, Germany
- Computational Biology & Applied Algorithmics, Max Planck Institute for Informatics, Saarland Informatics Campus, 66123 Saarbrücken, Germany
| | - Aurélien Ginolhac
- Life Sciences Research Unit, University of Luxembourg, L-4367 Belvaux, Luxembourg
| | - Martine Schmitz
- Molecular Disease Mechanisms Group, Life Sciences Research Unit, University of Luxembourg, L-4367 Belvaux, Luxembourg
| | - Rashi Halder
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, L-4362, Luxembourg
| | - Peter Ebert
- Computational Biology & Applied Algorithmics, Max Planck Institute for Informatics, Saarland Informatics Campus, 66123 Saarbrücken, Germany
| | - Marcel H Schulz
- Excellence Cluster for Multimodal Computing and Interaction, Saarland Informatics Campus, 66123 Saarbrücken, Germany
- Computational Biology & Applied Algorithmics, Max Planck Institute for Informatics, Saarland Informatics Campus, 66123 Saarbrücken, Germany
| | - Thomas Sauter
- Life Sciences Research Unit, University of Luxembourg, L-4367 Belvaux, Luxembourg
| | - Lasse Sinkkonen
- Life Sciences Research Unit, University of Luxembourg, L-4367 Belvaux, Luxembourg
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23
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Knutsen HK, Alexander J, Barregård L, Bignami M, Brüschweiler B, Ceccatelli S, Cottrill B, Dinovi M, Edler L, Grasl-Kraupp B, Hogstrand C, Nebbia CS, Oswald IP, Petersen A, Rose M, Roudot AC, Schwerdtle T, Vleminckx C, Vollmer G, Wallace H, Fürst P, Håkansson H, Halldorsson T, Lundebye AK, Pohjanvirta R, Rylander L, Smith A, van Loveren H, Waalkens-Berendsen I, Zeilmaker M, Binaglia M, Gómez Ruiz JÁ, Horváth Z, Christoph E, Ciccolallo L, Ramos Bordajandi L, Steinkellner H, Hoogenboom LR. Risk for animal and human health related to the presence of dioxins and dioxin-like PCBs in feed and food. EFSA J 2018; 16:e05333. [PMID: 32625737 PMCID: PMC7009407 DOI: 10.2903/j.efsa.2018.5333] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The European Commission asked EFSA for a scientific opinion on the risks for animal and human health related to the presence of dioxins (PCDD/Fs) and DL-PCBs in feed and food. The data from experimental animal and epidemiological studies were reviewed and it was decided to base the human risk assessment on effects observed in humans and to use animal data as supportive evidence. The critical effect was on semen quality, following pre- and postnatal exposure. The critical study showed a NOAEL of 7.0 pg WHO2005-TEQ/g fat in blood sampled at age 9 years based on PCDD/F-TEQs. No association was observed when including DL-PCB-TEQs. Using toxicokinetic modelling and taking into account the exposure from breastfeeding and a twofold higher intake during childhood, it was estimated that daily exposure in adolescents and adults should be below 0.25 pg TEQ/kg bw/day. The CONTAM Panel established a TWI of 2 pg TEQ/kg bw/week. With occurrence and consumption data from European countries, the mean and P95 intake of total TEQ by Adolescents, Adults, Elderly and Very Elderly varied between, respectively, 2.1 to 10.5, and 5.3 to 30.4 pg TEQ/kg bw/week, implying a considerable exceedance of the TWI. Toddlers and Other Children showed a higher exposure than older age groups, but this was accounted for when deriving the TWI. Exposure to PCDD/F-TEQ only was on average 2.4- and 2.7-fold lower for mean and P95 exposure than for total TEQ. PCDD/Fs and DL-PCBs are transferred to milk and eggs, and accumulate in fatty tissues and liver. Transfer rates and bioconcentration factors were identified for various species. The CONTAM Panel was not able to identify reference values in most farm and companion animals with the exception of NOAELs for mink, chicken and some fish species. The estimated exposure from feed for these species does not imply a risk.
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24
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Hwang WB, Kim DJ, Oh GS, Park JH. Aryl Hydrocarbon Receptor Ligands Indoxyl 3-sulfate and Indole-3-carbinol Inhibit FMS-like Tyrosine Kinase 3 Ligand-induced Bone Marrow-derived plasmacytoid Dendritic Cell Differentiation. Immune Netw 2018; 18:e35. [PMID: 30402330 PMCID: PMC6215903 DOI: 10.4110/in.2018.18.e35] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 10/15/2018] [Accepted: 10/16/2018] [Indexed: 12/29/2022] Open
Abstract
Aryl hydrocarbon receptor (AhR) regulates both innate and adaptive immune responses by sensing a variety of small synthetic and natural chemicals, which act as its ligands. AhR, which is expressed in dendritic cells (DCs), regulates the differentiation of DCs. However, effects of AhR on the differentiation of DCs are variable due to the heterogeneity of DCs in cell surface marker expression, anatomical location, and functional responses. The plasmacytoid DCs (pDCs), one of DC subsets, not only induce innate as well as adaptive immune responses by secreting type I interferons and pro-inflammatory cytokines, but also induce IL-10 producing regulatory T cell or anergy or deletion of antigen-specific T cells. We showed here that AhR ligands indoxyl 3-sulfate (I3S) and indole-3-carbinol (I3C) inhibited the development of pDCs derived from bone marrow (BM) precursors induced by FMS-like tyrosine kinase 3 ligand (Flt3L). I3S and I3C downregulated the expression of signal transducer and activator of transcription 3 (STAT3) and E2-2 (Tcf4). In mice orally treated with I3S and I3C, oral tolerance to dinitrofluorobenzene was impaired and the proportion of CD11c+B220+ cells in mesenteric lymph nodes was reduced. These data demonstrate that AhR negatively regulates the development of pDCs from BM precursors induced by Flt3L, probably via repressing the expression of STAT3.
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Affiliation(s)
- Won-Bhin Hwang
- Department of Biology, Changwon National University, Changwon 51140, Korea
| | - Da-Jeong Kim
- Department of Biology, Changwon National University, Changwon 51140, Korea
| | - Gap-Soo Oh
- Department of Biology, Changwon National University, Changwon 51140, Korea
| | - Joo-Hung Park
- Department of Biology, Changwon National University, Changwon 51140, Korea
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25
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Riemschneider S, Kohlschmidt J, Fueldner C, Esser C, Hauschildt S, Lehmann J. Aryl hydrocarbon receptor activation by benzo(a)pyrene inhibits proliferation of myeloid precursor cells and alters the differentiation state as well as the functional phenotype of murine bone marrow-derived macrophages. Toxicol Lett 2018; 296:106-113. [DOI: 10.1016/j.toxlet.2018.07.050] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 07/13/2018] [Accepted: 07/26/2018] [Indexed: 12/17/2022]
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Ng ML, Yarla NS, Menschikowski M, Sukocheva OA. Regulatory role of sphingosine kinase and sphingosine-1-phosphate receptor signaling in progenitor/stem cells. World J Stem Cells 2018; 10:119-133. [PMID: 30310531 PMCID: PMC6177561 DOI: 10.4252/wjsc.v10.i9.119] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 07/27/2018] [Accepted: 08/05/2018] [Indexed: 02/06/2023] Open
Abstract
Balanced sphingolipid signaling is important for the maintenance of homeostasis. Sphingolipids were demonstrated to function as structural components, second messengers, and regulators of cell growth and survival in normal and disease-affected tissues. Particularly, sphingosine kinase 1 (SphK1) and its product sphingosine-1-phosphate (S1P) operate as mediators and facilitators of proliferation-linked signaling. Unlimited proliferation (self-renewal) within the regulated environment is a hallmark of progenitor/stem cells that was recently associated with the S1P signaling network in vasculature, nervous, muscular, and immune systems. S1P was shown to regulate progenitor-related characteristics in normal and cancer stem cells (CSCs) via G-protein coupled receptors S1Pn (n = 1 to 5). The SphK/S1P axis is crucially involved in the regulation of embryonic development of vasculature and the nervous system, hematopoietic stem cell migration, regeneration of skeletal muscle, and development of multiple sclerosis. The ratio of the S1P receptor expression, localization, and specific S1P receptor-activated downstream effectors influenced the rate of self-renewal and should be further explored as regeneration-related targets. Considering malignant transformation, it is essential to control the level of self-renewal capacity. Proliferation of the progenitor cell should be synchronized with differentiation to provide healthy lifelong function of blood, immune systems, and replacement of damaged or dead cells. The differentiation-related role of SphK/S1P remains poorly assessed. A few pioneering investigations explored pharmacological tools that target sphingolipid signaling and can potentially confine and direct self-renewal towards normal differentiation. Further investigation is required to test the role of the SphK/S1P axis in regulation of self-renewal and differentiation.
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Affiliation(s)
- Mei Li Ng
- Centenary Institute of Cancer Medicine and Cell Biology, Sydney NSW 2050, Australia
| | - Nagendra S Yarla
- Department of Biochemistry and Bioinformatics, Institute of Science, GITAM University, Rushikonda, Visakhapatnam 530 045, Andhra Pradesh, India
| | - Mario Menschikowski
- Institute of Clinical Chemistry and Laboratory Medicine, Carl Gustav Carus University Hospital, Technical University of Dresden, Dresden D-01307, Germany
| | - Olga A Sukocheva
- College of Nursing and Health Sciences, Flinders University of South Australia, Bedford Park SA 5042, Australia
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Rannug A, Rannug U. The tryptophan derivative 6-formylindolo[3,2-b]carbazole, FICZ, a dynamic mediator of endogenous aryl hydrocarbon receptor signaling, balances cell growth and differentiation. Crit Rev Toxicol 2018; 48:555-574. [PMID: 30226107 DOI: 10.1080/10408444.2018.1493086] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The aryl hydrocarbon receptor (AHR) is not essential to survival, but does act as a key regulator of many normal physiological events. The role of this receptor in toxicological processes has been studied extensively, primarily employing the high-affinity ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). However, regulation of physiological responses by endogenous AHR ligands remains to be elucidated. Here, we review developments in this field, with a focus on 6-formylindolo[3,2-b]carbazole (FICZ), the endogenous ligand with the highest affinity to the receptor reported to date. The binding of FICZ to different isoforms of the AHR seems to be evolutionarily well conserved and there is a feedback loop that controls AHR activity through metabolic degradation of FICZ via the highly inducible cytochrome P450 1A1. Several investigations provide strong evidence that FICZ plays a critical role in normal physiological processes and can ameliorate immune diseases with remarkable efficiency. Low levels of FICZ are pro-inflammatory, providing resistance to pathogenic bacteria, stimulating the anti-tumor functions, and promoting the differentiation of cancer cells by repressing genes in cancer stem cells. In contrast, at high concentrations FICZ behaves in a manner similar to TCDD, exhibiting toxicity toward fish and bird embryos, immune suppression, and activation of cancer progression. The findings are indicative of a dual role for endogenously activated AHR in barrier tissues, aiding clearance of infections and suppressing immunity to terminate a vicious cycle that might otherwise lead to disease. There is not much support for the AHR ligand-specific immune responses proposed, the differences between FICZ and TCDD in this context appear to be explained by the rapid metabolism of FICZ.
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Affiliation(s)
- Agneta Rannug
- a Karolinska Institutet, Institute of Environmental Medicine , Stockholm , Sweden
| | - Ulf Rannug
- b Department of Molecular Biosciences , The Wenner-Gren Institute, Stockholm University , Stockholm , Sweden
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Janosik T, Rannug A, Rannug U, Wahlström N, Slätt J, Bergman J. Chemistry and Properties of Indolocarbazoles. Chem Rev 2018; 118:9058-9128. [PMID: 30191712 DOI: 10.1021/acs.chemrev.8b00186] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The indolocarbazoles are an important class of nitrogen heterocycles which has evolved significantly in recent years, with numerous studies focusing on their diverse biological effects, or targeting new materials with potential applications in organic electronics. This review aims at providing a broad survey of the chemistry and properties of indolocarbazoles from an interdisciplinary point of view, with particular emphasis on practical synthetic aspects, as well as certain topics which have not been previously accounted for in detail, such as the occurrence, formation, biological activities, and metabolism of indolo[3,2- b]carbazoles. The literature of the past decade forms the basis of the text, which is further supplemented with older key references.
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Affiliation(s)
- Tomasz Janosik
- Research Institutes of Sweden , Bioscience and Materials, RISE Surface, Process and Formulation , SE-151 36 Södertälje , Sweden
| | - Agneta Rannug
- Institute of Environmental Medicine , Karolinska Institutet , SE-171 77 Stockholm , Sweden
| | - Ulf Rannug
- Department of Molecular Biosciences, The Wenner-Gren Institute , Stockholm University , SE-106 91 Stockholm , Sweden
| | | | - Johnny Slätt
- Department of Chemistry, Applied Physical Chemistry , KTH Royal Institute of Technology , SE-100 44 Stockholm , Sweden
| | - Jan Bergman
- Karolinska Institutet , Department of Biosciences and Nutrition , SE-141 83 Huddinge , Sweden
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MicroRNAs as Novel Biomarkers of Deployment Status and Exposure to Polychlorinated Dibenzo-p-Dioxins/Dibenzofurans. J Occup Environ Med 2018; 58:S89-96. [PMID: 27501109 DOI: 10.1097/jom.0000000000000769] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVE To determine if service members deployed to locations with open air burn pits have different serum microRNA (miRNA) profiles after deployment compared with length-of-service matched, non-deployed individuals. We also tested for correlations between miRNA and serum levels of Polychlorinated Dibenzo-p-Dioxins/Dibenzofurans (PCDD/PCDFs). METHODS MiRNAs were isolated and quantified by PCR array. Groups were analyzed for differences in miRNA expression. Correlations between serum miRNA and PCDD/PCDFs were assessed with a linear regression model. RESULTS Several miRNAs were differentially expressed after deployment and a partially overlapping set of miRNAs were identified between deployed and non-deployed individuals. Significant correlations between miRNAs and PCDD/PCDFs were identified. CONCLUSIONS Serum miRNA levels show a link between deployment to locations with open burn pits and environmental exposures that can take place during deployment.
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Cannavo S, Trimarchi F, Ferraù F. Acromegaly, genetic variants of the aryl hydrocarbon receptor pathway and environmental burden. Mol Cell Endocrinol 2017; 457:81-88. [PMID: 27998805 DOI: 10.1016/j.mce.2016.12.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Revised: 12/15/2016] [Accepted: 12/16/2016] [Indexed: 12/13/2022]
Abstract
Increasing evidence suggests that environmental contaminants can exert endocrine disruptors activities and that pollution exposition can have a role in tumorigenic processes. Several environmental pollutants have been shown to affect pituitary cells biology and function. The aryl hydrocarbon receptor (AHR) pathway is involved in xenobiotics' metabolism and in tumorigenesis. A deregulation of the AHR pathway could have a role in pituitary tumours' pathophysiology, especially in the GH secreting ones. AHR-interacting protein (AIP) is one of the key partners of AHR and is implicated in pituitary tumours' pathogenesis. Moreover, an increased prevalence of acromegaly has been reported in a highly polluted area of the province of Messina (Sicily, Italy). Nevertheless, at present, few data are available about the potential role of environmental factors in the pathogenesis and clinical expression of GH secreting pituitary tumours. This review is aimed at discussing the evidences on the potential links among environmental pollutants, the AHR pathway and the pathophysiology of GH-secreting pituitary adenomas.
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Affiliation(s)
- S Cannavo
- Department of Clinical and Experimental Medicine - Endocrinology Unit, University of Messina, Italy
| | - F Trimarchi
- Department of Clinical and Experimental Medicine - Endocrinology Unit, University of Messina, Italy
| | - F Ferraù
- Department of Clinical and Experimental Medicine - Endocrinology Unit, University of Messina, Italy.
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31
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Aryl hydrocarbon receptor (AHR): "pioneer member" of the basic-helix/loop/helix per-Arnt-sim (bHLH/PAS) family of "sensors" of foreign and endogenous signals. Prog Lipid Res 2017; 67:38-57. [PMID: 28606467 DOI: 10.1016/j.plipres.2017.06.001] [Citation(s) in RCA: 177] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 05/05/2017] [Accepted: 06/05/2017] [Indexed: 12/21/2022]
Abstract
The basic-helix/loop/helix per-Arnt-sim (bHLH/PAS) family comprises many transcription factors, found throughout all three kingdoms of life; bHLH/PAS members "sense" innumerable intracellular and extracellular "signals" - including endogenous compounds, foreign chemicals, gas molecules, redox potential, photons (light), gravity, heat, and osmotic pressure. These signals then initiate downstream signaling pathways involved in responding to that signal. The term "PAS", abbreviation for "per-Arnt-sim" was first coined in 1991. Although the mouse Arnt gene was not identified until 1991, evidence of its co-transcriptional binding partner, aryl hydrocarbon receptor (AHR), was first reported in 1974 as a "sensor" of foreign chemicals, up-regulating cytochrome P450 family 1 (CYP1) and other enzyme activities that usually metabolize the signaling chemical. Within a few years, AHR was proposed also to participate in inflammation. The mouse [Ah] locus was shown (1973-1989) to be relevant to chemical carcinogenesis, mutagenesis, toxicity and teratogenesis, the mouse Ahr gene was cloned in 1992, and the first Ahr(-/-) knockout mouse line was reported in 1995. After thousands of studies from the early 1970s to present day, we now realize that AHR participates in dozens of signaling pathways involved in critical-life processes, affecting virtually every organ and cell-type in the animal, including many invertebrates.
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32
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Schulte KW, Green E, Wilz A, Platten M, Daumke O. Structural Basis for Aryl Hydrocarbon Receptor-Mediated Gene Activation. Structure 2017; 25:1025-1033.e3. [PMID: 28602820 DOI: 10.1016/j.str.2017.05.008] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 04/28/2017] [Accepted: 05/10/2017] [Indexed: 12/15/2022]
Abstract
The aryl hydrocarbon receptor (AHR) and the AHR nuclear translocator (ARNT) constitute a heterodimeric basic helix-loop-helix-Per-ARNT-Sim (bHLH-PAS) domain containing transcription factor with central functions in development and cellular homeostasis. AHR is activated by xenobiotics, notably dioxin, as well as by exogenous and endogenous metabolites. Modulation of AHR activity holds promise for the treatment of diseases featuring altered cellular homeostasis, such as cancer or autoimmune disorders. Here, we present the crystal structure of a heterodimeric AHR:ARNT complex containing the PAS A and bHLH domain bound to its target DNA. The structure provides insights into the DNA binding mode of AHR and elucidates how stable dimerization of AHR:ARNT is achieved through sophisticated domain interplay via three specific interfaces. Using mutational analyses, we prove the relevance of the observed interfaces for AHR-mediated gene activation. Thus, our work establishes the structural basis of AHR assembly and DNA interaction and provides a template for targeted drug design.
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Affiliation(s)
- Kathrin Wiebke Schulte
- Crystallography Department, Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany; Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustrasse 6, 14195 Berlin, Germany
| | - Edward Green
- Department of Neurology, University Hospital Heidelberg and National Center for Tumor Diseases, 69120 Heidelberg, Germany; Clinical Cooperation Unit Neuroimmunology and Brain Tumor Immunology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Annabel Wilz
- Clinical Cooperation Unit Neuroimmunology and Brain Tumor Immunology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Michael Platten
- Department of Neurology, University Hospital Heidelberg and National Center for Tumor Diseases, 69120 Heidelberg, Germany; Clinical Cooperation Unit Neuroimmunology and Brain Tumor Immunology, German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany; Department of Neurology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany.
| | - Oliver Daumke
- Crystallography Department, Max-Delbrück-Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany; Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustrasse 6, 14195 Berlin, Germany.
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Whitehead A, Clark BW, Reid NM, Hahn ME, Nacci D. When evolution is the solution to pollution: Key principles, and lessons from rapid repeated adaptation of killifish ( Fundulus heteroclitus) populations. Evol Appl 2017; 10:762-783. [PMID: 29151869 PMCID: PMC5680427 DOI: 10.1111/eva.12470] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 02/10/2017] [Indexed: 12/18/2022] Open
Abstract
For most species, evolutionary adaptation is not expected to be sufficiently rapid to buffer the effects of human‐mediated environmental changes, including environmental pollution. Here we review how key features of populations, the characteristics of environmental pollution, and the genetic architecture underlying adaptive traits, may interact to shape the likelihood of evolutionary rescue from pollution. Large populations of Atlantic killifish (Fundulus heteroclitus) persist in some of the most contaminated estuaries of the United States, and killifish studies have provided some of the first insights into the types of genomic changes that enable rapid evolutionary rescue from complexly degraded environments. We describe how selection by industrial pollutants and other stressors has acted on multiple populations of killifish and posit that extreme nucleotide diversity uniquely positions this species for successful evolutionary adaptation. Mechanistic studies have identified some of the genetic underpinnings of adaptation to a well‐studied class of toxic pollutants; however, multiple genetic regions under selection in wild populations seem to reflect more complex responses to diverse native stressors and/or compensatory responses to primary adaptation. The discovery of these pollution‐adapted killifish populations suggests that the evolutionary influence of anthropogenic stressors as selective agents occurs widely. Yet adaptation to chemical pollution in terrestrial and aquatic vertebrate wildlife may rarely be a successful “solution to pollution” because potentially adaptive phenotypes may be complex and incur fitness costs, and therefore be unlikely to evolve quickly enough, especially in species with small population sizes.
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Affiliation(s)
- Andrew Whitehead
- Department of Environmental Toxicology University of California Davis Davis CA USA
| | - Bryan W Clark
- Atlantic Ecology Division National Health and Environmental Effects Research Laboratory Office of Research and Development Oak Ridge Institute for Science and Education US Environmental Protection Agency Narragansett RI USA
| | - Noah M Reid
- Department of Molecular and Cell Biology University of Connecticut Storrs CT USA
| | - Mark E Hahn
- Department of Biology Woods Hole Oceanographic Institution Woods Hole MA USA.,Superfund Research Program Boston University Boston MA USA
| | - Diane Nacci
- Atlantic Ecology Division National Health and Environmental Effects Research Laboratory Office of Research and Development US Environmental Protection Agency Narragansett RI USA
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34
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Bock KW. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD)-mediated deregulation of myeloid and sebaceous gland stem/progenitor cell homeostasis. Arch Toxicol 2017; 91:2295-2301. [PMID: 28386637 DOI: 10.1007/s00204-017-1965-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 03/21/2017] [Indexed: 01/09/2023]
Abstract
Studies of TCDD toxicity stimulated identification of the responsible aryl hydrocarbon receptor (AHR), a multifunctional, ligand-activated transcription factor of the basic helix-loop-helix/Per-Arnt-Sim family. Accumulating evidence suggests a role of this receptor in homeostasis of stem/progenitor cells, in addition to its known role in xenobiotic metabolism. (1) Regulation of myelopoiesis is complex. As one example, AHR-mediated downregulation of human CD34+ progenitor differentiation to monocytes/macrophages is discussed. (2) Accumulation of TCDD in sebum leads to deregulation of sebocyte differentiation via Blimp1-mediated inhibition of c-Myc signaling and stimulation of Wnt-mediated proliferation of interfollicular epidermis. The resulting sebaceous gland atrophy and formation of dermal cysts may explain the pathogenesis of chloracne, the hallmark of TCDD toxicity. (3) TCDD treatment of confluent liver stem cell-like rat WB-F344 cells leads to release from cell-cell contact inhibition via AHR-mediated crosstalk with multiple signaling pathways. Further work is needed to delineate AHR function in crosstalk with other signaling pathways.
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Affiliation(s)
- Karl Walter Bock
- Department of Toxicology, Institute of Pharmacology and Toxicology, University of Tübingen, Tübingen, Germany.
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35
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Hahn ME, Karchner SI, Merson RR. Diversity as Opportunity: Insights from 600 Million Years of AHR Evolution. CURRENT OPINION IN TOXICOLOGY 2017; 2:58-71. [PMID: 28286876 DOI: 10.1016/j.cotox.2017.02.003] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The aryl hydrocarbon receptor (AHR) was for many years of interest only to pharmacologists and toxicologists. However, this protein has fundamental roles in biology that are being revealed through studies in diverse animal species. The AHR is an ancient protein. AHR homologs exist in most major groups of modern bilaterian animals, including deuterostomes (chordates, hemichordates, echinoderms) and the two major clades of protostome invertebrates [ecdysozoans (e.g. arthropods and nematodes) and lophotrochozoans (e.g. molluscs and annelids)]. AHR homologs also have been identified in cnidarians such as the sea anemone Nematostella and in the genome of Trichoplax, a placozoan. Bilaterians, cnidarians, and placozoans form the clade Eumetazoa, whose last common ancestor lived approximately 600 million years ago (MYA). The presence of AHR homologs in modern representatives of all these groups indicates that the original eumetazoan animal possessed an AHR homolog. Studies in invertebrates and vertebrates reveal parallel functions of AHR in the development and function of sensory neural systems, suggesting that these may be ancestral roles. Vertebrate animals are characterized by the expansion and diversification of AHRs, via gene and genome duplications, from the ancestral protoAHR into at least five classes of AHR-like proteins: AHR, AHR1, AHR2, AHR3, and AHRR. The evolution of multiple AHRs in vertebrates coincided with the acquisition of high-affinity binding of halogenated and polynuclear aromatic hydrocarbons and the emergence of adaptive functions involving regulation of xenobiotic-metabolizing enzymes and roles in adaptive immunity. The existence of multiple AHRs may have facilitated subfunction partitioning and specialization of specific AHR types in some taxa. Additional research in diverse model and non-model species will continue to enrich our understanding of AHR and its pleiotropic roles in biology and toxicology.
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Affiliation(s)
- Mark E Hahn
- Biology Department, Woods Hole Oceanographic Institution, MS-32, Woods Hole, MA 02543, USA
| | - Sibel I Karchner
- Biology Department, Woods Hole Oceanographic Institution, MS-32, Woods Hole, MA 02543, USA
| | - Rebeka R Merson
- Biology Department, Rhode Island College, 600 Mt. Pleasant Avenue, 251 Fogarty Life Sciences, Providence, RI 02908
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Bock KW. From dioxin toxicity to putative physiologic functions of the human Ah receptor in homeostasis of stem/progenitor cells. Biochem Pharmacol 2017; 123:1-7. [DOI: 10.1016/j.bcp.2016.06.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 06/23/2016] [Indexed: 01/16/2023]
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Fracchiolla NS, Annaloro C, Guidotti F, Fattizzo B, Cortelezzi A. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) role in hematopoiesis and in hematologic diseases: A critical review. Toxicology 2016; 374:60-68. [PMID: 27765685 DOI: 10.1016/j.tox.2016.10.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/03/2016] [Accepted: 10/13/2016] [Indexed: 12/12/2022]
Abstract
Dioxin exposure and its effect on hematopoiesis and cancer have been largely investigated in both human and non-human settings. Here we systematically reviewed literature to address the question of what we know about TCDD biology and exposure. Most effects are due to TCDD interaction with a receptor of xenobiotics called AHR, which is ubiquitously represented and also works on hematopoietic myeloid and lymphoid stem cells, inducing proliferation and stem cell release from bone marrow to peripheral circulation. Epidemiologic studies on TCDD exposure demonstrated an association with onco-hematologic diseases, particularly with non Hodgkin lymphomas and multiple myeloma, and non hematologic cancers, such as sarcomas, although these relationships are affected by multiple confounding factors.
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Affiliation(s)
- Nicola Stefano Fracchiolla
- UO Onco-Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via F. Sforza 35, 20100, Milano, Italy.
| | - Claudio Annaloro
- UO Onco-Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via F. Sforza 35, 20100, Milano, Italy
| | - Francesca Guidotti
- UO Onco-Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via F. Sforza 35, 20100, Milano, Italy
| | - Bruno Fattizzo
- UO Onco-Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via F. Sforza 35, 20100, Milano, Italy
| | - Agostino Cortelezzi
- UO Onco-Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via F. Sforza 35, 20100, Milano, Italy; UO Onco-Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via F Sforza 35, 20100, Milano, Italy
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38
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Estrogen receptor beta polymorphisms and cognitive performance in women: associations and modifications by genetic and environmental influences. J Neural Transm (Vienna) 2016; 123:1369-1379. [DOI: 10.1007/s00702-016-1620-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 09/05/2016] [Indexed: 01/18/2023]
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39
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Larsen MC, N'Jai AU, Alexander DL, Rondelli CM, Forsberg EC, Czuprynski CJ, Jefcoate CR. Cyp1b1-mediated suppression of lymphoid progenitors in bone marrow by polycyclic aromatic hydrocarbons coordinately impacts spleen and thymus: a selective role for the Ah Receptor. Pharmacol Res Perspect 2016; 4:e00245. [PMID: 28116098 PMCID: PMC5242170 DOI: 10.1002/prp2.245] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 05/26/2016] [Indexed: 02/05/2023] Open
Abstract
Bone marrow (BM) hematopoietic stem cells differentiate to common lymphoid progenitors (CLP) that emigrate to the thymus to form T cells or differentiate into immature B cells that then migrate to the spleen for maturation. Rapid in vivo suppression of BM progenitor cells by a single oral or intraperitoneal dose of 7,12-dimethylbenz(a)anthracene (DMBA) subsequently decreased mature lymphoid populations in BM, spleen, and thymus. These suppressions depended on BM CYP1B1, but not on aryl hydrocarbon receptor (AhR) activity. Suppression of pre-B colony formation at 6 h, correlated with subsequent decreases in mature BM, spleen, and thymus populations (48-168 h). Thymus T-cell ratios were unaffected, suggesting low local toxicity. DMBA treatment suppressed progenitor cells 24-h post treatment in wild type (WT), AhRb mice, but not in Cyp1b1-ko mice. The stem cell populations were sustained. Benzo(a)pyrene (BP) mediated a similar progenitor suppression up to 6 h, but reversal rapidly ensued. This recovery was absent in mice with a polycyclic aromatic hydrocarbon (PAH)-resistant, AhRd genotype. This AhR-dependent progenitor recovery with BP induction accounts for the absence of suppression of B220+ BM and spleen populations at 48-168 h. However, DMBA and BP produced similar profiles for thymus cell suppression, independent of AhR genotype. Thus, lymphoid progenitors may exit the BM to the thymus prior to the BP reversal. This progenitor recovery is associated with elevated chemokines and cytokines that depend on AhR-mediated induction of CYP1A1. This response increased constitutively in Cyp1b1-ko BM, demonstrating that CYP1B1 metabolizes local stimulants that impact a basal progenitor protection process.
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Affiliation(s)
| | - Alhaji U N'Jai
- Molecular and Environmental Toxicology Center University of Wisconsin Madison Wisconsin 53706; Department of Pathobiological Sciences University of Wisconsin Madison Wisconsin 53706
| | - David L Alexander
- Department of Biomolecular Engineering Institute for the Biology of Stem Cells, University of California Santa Cruz California 95064
| | - Catherine M Rondelli
- Molecular and Environmental Toxicology Center University of Wisconsin Madison Wisconsin 53706
| | - E C Forsberg
- Department of Biomolecular Engineering Institute for the Biology of Stem Cells, University of California Santa Cruz California 95064
| | - Charles J Czuprynski
- Molecular and Environmental Toxicology Center University of Wisconsin Madison Wisconsin 53706; Department of Pathobiological Sciences University of Wisconsin Madison Wisconsin 53706; Food Research Institute University of Wisconsin Madison Wisconsin 53706
| | - Colin R Jefcoate
- Department of Cell and Regenerative Biology University of Wisconsin Madison Wisconsin; Molecular and Environmental Toxicology Center University of Wisconsin Madison Wisconsin 53706
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40
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Ko CI, Fan Y, de Gannes M, Wang Q, Xia Y, Puga A. Repression of the Aryl Hydrocarbon Receptor Is Required to Maintain Mitotic Progression and Prevent Loss of Pluripotency of Embryonic Stem Cells. Stem Cells 2016; 34:2825-2839. [DOI: 10.1002/stem.2456] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 06/20/2016] [Accepted: 06/21/2016] [Indexed: 12/14/2022]
Affiliation(s)
- Chia-I Ko
- Department of Environmental Health and Center for Environmental Genetics; University of Cincinnati College of Medicine; Cincinnati Ohio USA
| | - Yunxia Fan
- Department of Environmental Health and Center for Environmental Genetics; University of Cincinnati College of Medicine; Cincinnati Ohio USA
| | - Matthew de Gannes
- Department of Environmental Health and Center for Environmental Genetics; University of Cincinnati College of Medicine; Cincinnati Ohio USA
| | - Qin Wang
- Department of Environmental Health and Center for Environmental Genetics; University of Cincinnati College of Medicine; Cincinnati Ohio USA
| | - Ying Xia
- Department of Environmental Health and Center for Environmental Genetics; University of Cincinnati College of Medicine; Cincinnati Ohio USA
| | - Alvaro Puga
- Department of Environmental Health and Center for Environmental Genetics; University of Cincinnati College of Medicine; Cincinnati Ohio USA
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Laiosa MD, Tate ER, Ahrenhoerster LS, Chen Y, Wang D. Effects of Developmental Activation of the Aryl Hydrocarbon Receptor by 2,3,7,8-Tetrachlorodibenzo-p-dioxin on Long-term Self-renewal of Murine Hematopoietic Stem Cells. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:957-65. [PMID: 26495820 PMCID: PMC4937855 DOI: 10.1289/ehp.1509820] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 10/15/2015] [Indexed: 05/19/2023]
Abstract
BACKGROUND Human epidemiological and animal studies suggest that developmental exposure to contaminants that activate the aryl hydrocarbon receptor (AHR) lead to suppression of immune system function throughout life. The persistence of immune deficiency throughout life suggests that the cellular target of AHR activation is a fetal hematopoietic progenitor or stem cell. OBJECTIVES The aim of this study was to identify the effects of transplacental exposure to an AHR agonist on long-term self-renewal of fetal hematopoietic stem cells. METHODS Pregnant C57BL/6 or AHR+/- mice were exposed to the AHR agonist, 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD). On day 14 of gestation, hematopoietic progenitors from wild-type or AHR-deficient fetuses were placed into in vitro T-lymphocyte differentiation cultures to identify the effects of transplacental TCDD on AHR activation in the fetus. We next analyzed the fetal hematopoietic progenitor cells for changes in reactive oxygen species (ROS). Finally, hematopoietic progenitors from fetuses exposed transplacentally to TCDD were mixed 1:1 with cells from congenic controls and used to reconstitute lethally irradiated recipients for analysis of long-term self-renewal potential. RESULTS Our findings suggested that the effects of TCDD on the developing hematopoietic system were mediated by direct AHR activation in the fetus. Furthermore, developmental AHR activation by TCDD increased ROS in the fetal hematopoietic stem cells, and the elevated ROS was associated with a reduced capacity of the TCDD-exposed fetal cells to compete with control cells in a mixed competitive irradiation/reconstitution assay. CONCLUSIONS Our findings indicate that AHR activation by TCDD in the fetus during pregnancy leads to impairment of long-term self-renewal of hematopoietic stem cells. CITATION Laiosa MD, Tate ER, Ahrenhoerster LS, Chen Y, Wang D. 2016. Effects of developmental activation of the aryl hydrocarbon receptor by 2,3,7,8-tetrachlorodibenzo-p-dioxin on long-term self-renewal of murine hematopoietic stem cells. Environ Health Perspect 124:957-965; http://dx.doi.org/10.1289/ehp.1509820.
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Affiliation(s)
- Michael D. Laiosa
- Joseph J. Zilber School of Public Health, University of Wisconsin–Milwaukee, Milwaukee, Wisconsin, USA
- Address correspondence to M.D. Laiosa, Joseph J. Zilber School of Public Health, University of Wisconsin–Milwaukee, 3335 North Maryland Ave., Kenwood Interdisciplinary Complex Room 5071, Milwaukee, WI 53211 USA. Telephone: (414) 229-2279. E-mail:
| | - Everett R. Tate
- Joseph J. Zilber School of Public Health, University of Wisconsin–Milwaukee, Milwaukee, Wisconsin, USA
| | - Lori S. Ahrenhoerster
- Joseph J. Zilber School of Public Health, University of Wisconsin–Milwaukee, Milwaukee, Wisconsin, USA
| | - Yuhong Chen
- Blood Research Institute, BloodCenter of Wisconsin, Milwaukee, Wisconsin, USA
| | - Demin Wang
- Blood Research Institute, BloodCenter of Wisconsin, Milwaukee, Wisconsin, USA
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Pérez Sáez JM, Bussmann LE, Barañao JL, Bussmann UA. Improvement of Chicken Primordial Germ Cell Maintenance In Vitro by Blockade of the Aryl Hydrocarbon Receptor Endogenous Activity. Cell Reprogram 2016; 18:154-61. [PMID: 27253627 PMCID: PMC4900192 DOI: 10.1089/cell.2016.0015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Primordial germ cells (PGCs) are the undifferentiated progenitors of gametes. Germline competent PGCs can be developed as a cell-based system for genetic modification in chickens, which provides a valuable tool for transgenic technology with both research and industrial applications. This implies manipulation of PGCs, which, in recent years, encouraged a lot of research focused on the study of PGCs and the way of improving their culture. The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that besides mediating toxic responses to environmental contaminants plays pivotal physiological roles in various biological processes. Since a novel compound that acts as an antagonist of this receptor has been reported to promote expansion of hematopoietic stem cells, we conducted the present study with the aim of determining whether addition of an established AHR antagonist to the standard culture medium used nowadays for in vitro chicken PGCs culture improves ex vivo expansion. We have found that addition of α-naphthoflavone in culture medium promotes the amplification of undifferentiated cells and that this effect is exerted by the blockade of AHR action. Our results constitute the first report of the successful use of a readily available AHR antagonist to improve avian PGCs expansion, and they further extend the knowledge of the effects of AHR modulation in undifferentiated cells.
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Affiliation(s)
- Juan M. Pérez Sáez
- Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Argentina
| | | | - J. Lino Barañao
- Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Argentina
- Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ursula A. Bussmann
- Instituto de Biología y Medicina Experimental-CONICET, Buenos Aires, Argentina
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Genome Editing of the CYP1A1 Locus in iPSCs as a Platform to Map AHR Expression throughout Human Development. Stem Cells Int 2016; 2016:2574152. [PMID: 27148368 PMCID: PMC4842384 DOI: 10.1155/2016/2574152] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 03/17/2016] [Indexed: 12/12/2022] Open
Abstract
The aryl hydrocarbon receptor (AHR) is a ligand activated transcription factor that increases the expression of detoxifying enzymes upon ligand stimulation. Recent studies now suggest that novel endogenous roles of the AHR exist throughout development. In an effort to create an optimized model system for the study of AHR signaling in several cellular lineages, we have employed a CRISPR/CAS9 genome editing strategy in induced pluripotent stem cells (iPSCs) to incorporate a reporter cassette at the transcription start site of one of its canonical targets, cytochrome P450 1A1 (CYP1A1). This cell line faithfully reports on CYP1A1 expression, with luciferase levels as its functional readout, when treated with an endogenous AHR ligand (FICZ) at escalating doses. iPSC-derived fibroblast-like cells respond to acute exposure to environmental and endogenous AHR ligands, and iPSC-derived hepatocytes increase CYP1A1 in a similar manner to primary hepatocytes. This cell line is an important innovation that can be used to map AHR activity in discrete cellular subsets throughout developmental ontogeny. As further endogenous ligands are proposed, this line can be used to screen for safety and efficacy and can report on the ability of small molecules to regulate critical cellular processes by modulating the activity of the AHR.
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44
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Park JH, Choi AJ, Kim SJ, Cheong SW, Jeong SY. AhR activation by 6-formylindolo[3,2-b]carbazole and 2,3,7,8-tetrachlorodibenzo-p-dioxin inhibit the development of mouse intestinal epithelial cells. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2016; 43:44-53. [PMID: 26950395 DOI: 10.1016/j.etap.2016.02.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 02/06/2016] [Accepted: 02/09/2016] [Indexed: 06/05/2023]
Abstract
The intestinal epithelium plays a central role in immune homeostasis in the intestine. AhR, a ligand-activated transcription factor, plays an important role in diverse physiological processes. The intestines are exposed to various exogenous and endogenous AhR ligands. Thus, AhR may regulate the intestinal homeostasis, directly acting on the development of intestinal epithelial cells (IEC). In this study, we demonstrated that 6-formylindolo[3,2-b]carbazole (FICZ) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) inhibited the in vitro development of mouse intestinal organoids. The number of Paneth cells in the small intestine and the depth of crypts of the small and large intestines were reduced in mice administrated with FICZ. Immunohistochemical and flow cytometric assays revealed that AhR was highly expressed in Lgr5(+) stem cells. FICZ inhibited Wnt signaling lowering the level of β-catenin protein. Gene expression analyses demonstrated that FICZ increased expression of Lgr5, Math1, BMP4, and Indian Hedgehog while inhibiting that of Lgr4.
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Affiliation(s)
- Joo-Hung Park
- Department of Biology, Changwon National University, Changwon, Kyungnam, 641-773, Korea.
| | - Ah-Jeong Choi
- Department of Biology, Changwon National University, Changwon, Kyungnam, 641-773, Korea
| | - Soo-Ji Kim
- Department of Biology, Changwon National University, Changwon, Kyungnam, 641-773, Korea
| | - Seon-Woo Cheong
- Department of Biology, Changwon National University, Changwon, Kyungnam, 641-773, Korea
| | - So-Yeon Jeong
- Department of Biology, Changwon National University, Changwon, Kyungnam, 641-773, Korea
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Stanford EA, Wang Z, Novikov O, Mulas F, Landesman-Bollag E, Monti S, Smith BW, Seldin DC, Murphy GJ, Sherr DH. The role of the aryl hydrocarbon receptor in the development of cells with the molecular and functional characteristics of cancer stem-like cells. BMC Biol 2016; 14:20. [PMID: 26984638 PMCID: PMC4794823 DOI: 10.1186/s12915-016-0240-y] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Accepted: 02/22/2016] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Self-renewing, chemoresistant breast cancer stem cells are believed to contribute significantly to cancer invasion, migration and patient relapse. Therefore, the identification of signaling pathways that regulate the acquisition of stem-like qualities is an important step towards understanding why patients relapse and towards development of novel therapeutics that specifically target cancer stem cell vulnerabilities. Recent studies identified a role for the aryl hydrocarbon receptor (AHR), an environmental carcinogen receptor implicated in cancer initiation, in normal tissue-specific stem cell self-renewal. These studies inspired the hypothesis that the AHR plays a role in the acquisition of cancer stem cell-like qualities. RESULTS To test this hypothesis, AHR activity in Hs578T triple negative and SUM149 inflammatory breast cancer cells were modulated with AHR ligands, shRNA or AHR-specific inhibitors, and phenotypic, genomic and functional stem cell-associated characteristics were evaluated. The data demonstrate that (1) ALDH(high) cells express elevated levels of Ahr and Cyp1b1 and Cyp1a1, AHR-driven genes, (2) AHR knockdown reduces ALDH activity by 80%, (3) AHR hyper-activation with several ligands, including environmental ligands, significantly increases ALDH1 activity, expression of stem cell- and invasion/migration-associated genes, and accelerates cell migration, (4) a significant correlation between Ahr or Cyp1b1 expression (as a surrogate marker for AHR activity) and expression of stem cell- and invasion/migration-associated gene sets is seen with genomic data obtained from 79 human breast cancer cell lines and over 1,850 primary human breast cancers, (5) the AHR interacts directly with Sox2, a master regulator of self-renewal; AHR ligands increase this interaction and nuclear SOX2 translocation, (6) AHR knockdown inhibits tumorsphere formation in low adherence conditions, (7) AHR inhibition blocks the rapid migration of ALDH(high) cells and reduces ALDH(high) cell chemoresistance, (8) ALDH(high) cells are highly efficient at initiating tumors in orthotopic xenografts, and (9) AHR knockdown inhibits tumor initiation and reduces tumor Aldh1a1, Sox2, and Cyp1b1 expression in vivo. CONCLUSIONS These data suggest that the AHR plays an important role in development of cells with cancer stem cell-like qualities and that environmental AHR ligands may exacerbate breast cancer by enhancing expression of these properties.
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Affiliation(s)
- Elizabeth A. Stanford
- />Department of Environmental Health, Boston University School of Public Health, 72 East Concord Street (R-408), Boston, Massachusetts 02118 USA
- />Boston University Molecular and Translational Medicine Program, 72 E. Concord Street, Boston, MA 02118 USA
| | - Zhongyan Wang
- />Department of Environmental Health, Boston University School of Public Health, 72 East Concord Street (R-408), Boston, Massachusetts 02118 USA
| | - Olga Novikov
- />Department of Environmental Health, Boston University School of Public Health, 72 East Concord Street (R-408), Boston, Massachusetts 02118 USA
- />Boston University Molecular and Translational Medicine Program, 72 E. Concord Street, Boston, MA 02118 USA
| | - Francesca Mulas
- />Department of Medicine, Boston University School of Medicine, Section of Computational Biomedicine, Boston, MA 02118 USA
| | - Esther Landesman-Bollag
- />Department of Medicine, Boston University School of Medicine, Section of Hematology and Oncology, 650 Albany Street, Boston, MA 02118 USA
| | - Stefano Monti
- />Department of Medicine, Boston University School of Medicine, Section of Computational Biomedicine, Boston, MA 02118 USA
| | - Brenden W. Smith
- />Boston University Molecular and Translational Medicine Program, 72 E. Concord Street, Boston, MA 02118 USA
- />Department of Medicine, Boston University School of Medicine, Section of Hematology and Oncology, 650 Albany Street, Boston, MA 02118 USA
- />Boston University and Boston Medical Center, Center for Regenerative Medicine (CReM), 710 Albany Street, Boston, MA 02118 USA
| | - David C. Seldin
- />Department of Medicine, Boston University School of Medicine, Section of Hematology and Oncology, 650 Albany Street, Boston, MA 02118 USA
| | - George J. Murphy
- />Department of Medicine, Boston University School of Medicine, Section of Hematology and Oncology, 650 Albany Street, Boston, MA 02118 USA
- />Boston University and Boston Medical Center, Center for Regenerative Medicine (CReM), 710 Albany Street, Boston, MA 02118 USA
| | - David H. Sherr
- />Department of Environmental Health, Boston University School of Public Health, 72 East Concord Street (R-408), Boston, Massachusetts 02118 USA
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Smirnova A, Wincent E, Vikström Bergander L, Alsberg T, Bergman J, Rannug A, Rannug U. Evidence for New Light-Independent Pathways for Generation of the Endogenous Aryl Hydrocarbon Receptor Agonist FICZ. Chem Res Toxicol 2015; 29:75-86. [PMID: 26686552 DOI: 10.1021/acs.chemrestox.5b00416] [Citation(s) in RCA: 329] [Impact Index Per Article: 36.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Activation of the aryl hydrocarbon receptor (AhR), a conserved transcription factor best known as a target for highly toxic halogenated substances such as dioxin, under normal xenobiotic-free conditions is of considerable scientific interest. We have demonstrated previously that a photoproduct of tryptophan, 6-formylindolo[3,2-b]carbazole (FICZ), fulfills the criteria for an endogenous ligand for this receptor and proposed that this compound is the enigmatic mediator of the physiological functions of AhR. Here, we describe novel light-independent pathways by which FICZ can be formed. The oxidant H2O2 was shown to convert tryptophan to FICZ on its own in the absence of light. The enzymatic deamination of tryptamine yielded indole-3-acetaldehyde (I3A), which then rearranged to FICZ and its oxidation product, indolo[3,2-b]carbazole-6-carboxylic acid (CICZ). Indole-3-pyruvate (I3P) also produced I3A, FICZ, and CICZ. Malassezia yeast species, which constitute a part of the normal skin microbiota, produce a number of AhR activators from tryptophan. We identified both FICZ and CICZ among those products. Formation of FICZ from tryptophan or I3P produces a complex mixture of indole derivatives, some of which are CYP1A1 inhibitors. These can hinder the cellular clearance of FICZ and thereby increase its power as an AhR agonist. We present a general molecular mechanism involving dehydrogenations and oxidative coupling for the formation of FICZ in which I3A is the important precursor. In conclusion, our results suggest that FICZ is likely to be formed systemically.
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Affiliation(s)
| | - Emma Wincent
- Institute of Environmental Medicine, Karolinska Institutet , SE-171 77 Stockholm, Sweden
| | | | | | - Jan Bergman
- Department of Biosciences at Novum, Karolinska Institutet , SE-141 57 Huddinge, Sweden
| | - Agneta Rannug
- Institute of Environmental Medicine, Karolinska Institutet , SE-171 77 Stockholm, Sweden
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47
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Park JH, Choi AJ, Kim SJ, Jeong SY. 3,3'-Diindolylmethane Inhibits Flt3L/GM-CSF-induced-bone Marrow-derived CD103(+) Dendritic Cell Differentiation Regulating Phosphorylation of STAT3 and STAT5. Immune Netw 2015; 15:278-90. [PMID: 26770182 PMCID: PMC4700404 DOI: 10.4110/in.2015.15.6.278] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 11/05/2015] [Accepted: 11/07/2015] [Indexed: 01/05/2023] Open
Abstract
The intestinal immune system maintains oral tolerance to harmless antigens or nutrients. One mechanism of oral tolerance is mediated by regulatory T cell (Treg)s, of which differentiation is regulated by a subset of dendritic cell (DC)s, primarily CD103+ DCs. The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor, plays an important role in regulating immunity. The intestines are exposed to various AhR ligands, including endogenous metabolites and phytochemicals. It was previously reported that AhR activation induced tolerogenic DCs in mice or in cultures of bone marrow-derived DCs. However, given the variety of tolerogenic DCs, which type of tolerogenic DCs is regulated by AhR remains unknown. In this study, we found that AhR ligand 3,3'-diindolylmethane (DIM) inhibited the development of CD103+ DCs from mouse bone marrow cells stimulated with Flt3L and GM-CSF. DIM interfered with phosphorylation of STAT3 and STAT5 inhibiting the expression of genes, including Id2, E2-2, IDO-1, and Aldh1a2, which are associated with DC differentiation and functions. Finally, DIM suppressed the ability of CD103+ DCs to induce Foxp3+ Tregs.
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Affiliation(s)
- Joo-Hung Park
- Department of Biology, Changwon National University, Changwon 51140, Korea
| | - Ah-Jeong Choi
- Department of Biology, Changwon National University, Changwon 51140, Korea
| | - Soo-Ji Kim
- Department of Biology, Changwon National University, Changwon 51140, Korea
| | - So-Yeon Jeong
- Department of Biology, Changwon National University, Changwon 51140, Korea
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48
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Mohammadi-Bardbori A, Vikström Bergander L, Rannug U, Rannug A. NADPH Oxidase-Dependent Mechanism Explains How Arsenic and Other Oxidants Can Activate Aryl Hydrocarbon Receptor Signaling. Chem Res Toxicol 2015; 28:2278-86. [PMID: 26535918 DOI: 10.1021/acs.chemrestox.5b00415] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The mechanisms explaining arsenic toxicity are not well understood, but physiological consequences of stimulated aryl hydrocarbon receptor (AHR) signaling both directly and through cross-talk with other pathways have been indicated. The aim of this study was to establish how arsenic interacts with AHR-mediated transcription. The human hepatoma cell line (HepG2-XRE-Luc) carrying a luciferase reporter under the control of two AHR response elements (AHREs) and immortalized human keratinocytes (HaCaT) were exposed to sodium arsenite (NaAsO2; As(3+)), alone or in combination with the endogenous high affinity AHR ligand 6-formylindolo[3,2-b]carbazole (FICZ). Luciferase activity, cytochrome P4501A1 (CYP1A1) activity, oxidative stress-related responses, metabolic clearance of FICZ, and NADPH oxidase (NOX) activity as well as nuclear factor (erythroid-derived 2)-like 2 (Nrf2)-dependent gene expression were measured. Arsenic inhibited CYP1A1 enzyme activity and reduced the metabolic clearance of FICZ. Arsenic also led to activated CYP1A1 transcription but only in cells grown in medium containing trace amounts of the endogenous ligand FICZ, pointing to an indirect mechanism of activation. Initially, arsenic caused dose-dependent inhibition of FICZ-activated AHR signaling, disturbed intracellular GSH status, and increased expression of oxidative stress-related genes. Silencing of NOX4, addition of N-acetylcystein, or pretreatment with arsenic itself attenuated the initial dose-dependent inhibition of AHR signaling. Arsenic pretreatment led to elevated GSH levels and sensitized the cells to ligand-dependent AHR signaling, while silencing of Nrf2 significantly reduced arsenic-mediated activation of the AHR. In addition, influence of NOX on AHR activation was also observed in cells treated with the SH-reactive metals cadmium, mercury, and nickel. Together, the results suggest that SH-reactive agents via a new and possibly general NOX/H2O2-dependent mechanism can interfere with the endogenous regulation of the AHR.
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Affiliation(s)
- Afshin Mohammadi-Bardbori
- Institute of Environmental Medicine, Karolinska Institutet , SE-171 77 Stockholm, Sweden.,Department of Pharmacology and Toxicology, School of Pharmacy, Shiraz University of Medical Sciences , Shiraz, Fars 71345-1583, Iran
| | | | - Ulf Rannug
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University , SE-106 91 Stockholm, Sweden
| | - Agneta Rannug
- Institute of Environmental Medicine, Karolinska Institutet , SE-171 77 Stockholm, Sweden
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Asai H, Hirata J, Hirano A, Hirai K, Seki S, Watanabe-Akanuma M. Activation of aryl hydrocarbon receptor mediates suppression of hypoxia-inducible factor-dependent erythropoietin expression by indoxyl sulfate. Am J Physiol Cell Physiol 2015; 310:C142-50. [PMID: 26561638 DOI: 10.1152/ajpcell.00172.2015] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 11/09/2015] [Indexed: 01/01/2023]
Abstract
Indoxyl sulfate (IS) is a representative uremic toxin that accumulates in the blood of patients with chronic kidney disease (CKD). In addition to the involvement in the progression of CKD, a recent report indicates that IS suppresses hypoxia-inducible factor (HIF)-dependent erythropoietin (EPO) production, suggesting that IS may also contribute to the progression of renal anemia. In this report, we provide evidence that aryl hydrocarbon receptor (AhR) mediates IS-induced suppression of HIF activation and subsequent EPO production. In HepG2 cells, IS at concentrations similar to the blood levels in CKD patients suppressed hypoxia- or cobalt chloride-induced EPO mRNA expression and transcriptional activation of HIF. IS also induced AhR activation, and AhR blockade resulted in abolishment of IS-induced suppression of HIF activation. The HIF transcription factor is a heterodimeric complex composed of HIF-α subunits (HIF-1α and HIF-2α) and AhR nuclear translocator (ARNT). IS suppressed nuclear accumulation of the HIF-α-ARNT complex accompanied by an increase of the AhR-ARNT complex in the nucleus, implying the involvement of interactions among AhR, HIF-α, and ARNT in the suppression mechanism. In rats, oral administration of indole, a metabolic precursor of IS, inhibited bleeding-induced elevation of renal EPO mRNA expression and plasma EPO concentration and strongly induced AhR activation in the liver and renal cortex tissues. Collectively, this study is the first to elucidate the detailed mechanism by which AhR plays an indispensable role in the suppression of HIF activation by IS. Hence, IS-induced activation of AhR may be a potential therapeutic target for treating renal anemia.
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Affiliation(s)
- Hirobumi Asai
- Safety Research Center, Kureha Corporation, Tokyo, Japan
| | - Junya Hirata
- Safety Research Center, Kureha Corporation, Tokyo, Japan
| | - Ayumi Hirano
- Safety Research Center, Kureha Corporation, Tokyo, Japan
| | - Kazuya Hirai
- Safety Research Center, Kureha Corporation, Tokyo, Japan
| | - Sayaka Seki
- Safety Research Center, Kureha Corporation, Tokyo, Japan
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50
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Rzemieniec J, Litwa E, Wnuk A, Lason W, Krzeptowski W, Kajta M. Selective Aryl Hydrocarbon Receptor Modulator 3,3'-Diindolylmethane Impairs AhR and ARNT Signaling and Protects Mouse Neuronal Cells Against Hypoxia. Mol Neurobiol 2015; 53:5591-606. [PMID: 26476840 DOI: 10.1007/s12035-015-9471-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 10/01/2015] [Indexed: 01/01/2023]
Abstract
The neuroprotective potential of 3,3'-diindolylmethane (DIM), which is a selective aryl hydrocarbon receptor modulator, has recently been shown in cellular and animal models of Parkinson's disease and lipopolysaccharide-induced inflammation. However, there are no data concerning the protective capacity and mechanisms of DIM action in neuronal cells exposed to hypoxia. The aim of the present study was to investigate the neuroprotective potential of DIM against the hypoxia-induced damage in mouse hippocampal cells in primary cultures, with a particular focus on DIM interactions with the aryl hydrocarbon receptor (AhR), its nuclear translocator ARNT, and estrogen receptor β (ERβ). In the present study, 18 h of hypoxia induced apoptotic processes, in terms of the mitochondrial membrane potential, activation of caspase-3, and fragmentation of cell nuclei. These effects were accompanied by substantial lactate dehydrogenase release and neuronal cell death. The results of the present study demonstrated strong neuroprotective and anti-apoptotic actions of DIM in hippocampal cells exposed to hypoxia. In addition, DIM decreased the Ahr and Arnt mRNA expression and stimulated Erβ mRNA expression level. DIM-induced mRNA alterations were mirrored by changes in protein levels, except for ERβ, as detected by ELISA, Western blotting, and immunofluorescence labeling. We also demonstrated that DIM decreased the expression of AhR-regulated CYP1A1. Using specific siRNAs, we provided evidence that impairment of AhR and ARNT, but not ERβ plays a key role in the neuroprotective action of DIM against hypoxia-induced cell damage. This study may have implication for identifying new agents that could protect neurons against hypoxia by targeting AhR/ARNT signaling.
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Affiliation(s)
- J Rzemieniec
- Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343, Krakow, Poland
| | - E Litwa
- Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343, Krakow, Poland
| | - A Wnuk
- Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343, Krakow, Poland
| | - W Lason
- Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343, Krakow, Poland
| | - W Krzeptowski
- Department of Cell Biology and Imaging, Confocal Microscopy Laboratory, Institute of Zoology, Jagiellonian University, 9 Gronostajowa Street, 30-387, Krakow, Poland
| | - M Kajta
- Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343, Krakow, Poland.
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