1
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Aldeli N, Soukkarie C, Hanano A. Transcriptional, hormonal and histological alterations in the ovaries of BALB/c mice exposed to TCDD in connection with multigenerational female infertility. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 258:114990. [PMID: 37156038 DOI: 10.1016/j.ecoenv.2023.114990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 05/01/2023] [Accepted: 05/04/2023] [Indexed: 05/10/2023]
Abstract
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the most toxic congener of dioxins, has a proven reproductive toxicity. Due to the lack of evidence on the multigenerational female reproductive toxicity of TCDD through the maternal exposure, the current study aims to evaluate, on the one hand, the acute reproductive toxicity of TCDD on adult female pre-gestational exposed to a critical single dose of TCDD (25 μg/kg) for a week (group referred to as AFnG; adult female/non-gestation). On the other hand, the transcription, hormonal and histological effects of TCDD on the females of two generations F1 and F2, were also investigated after the exposure of pregnant females to TCDD on gestational day 13 (GD13) (group referred to as AFG; adult female/gestation). First, our data showed alternations in the ovarian expressional pattern of certain key genes involved in the detoxification of TCDD as well as in the biosynthesis of steroidal hormones. The expression of Cyp1a1 was highly induced in TCDD-AFnG group, but reduced in both F1 and F2. While the transcripts levels of Cyp11a1 and 3βhsd2 were decreased, Cyp19a1 transcripts were increased as a function of TCDD exposure. This was synchronized with a dramatic increase in the level of estradiol hormone in the females of both experimental groups. Beside a significant reduce in their size and weight, ovaries of TCDD-exposed females showed serious histological alterations marked by atrophy of the ovary, congestion in the blood vessels, necrosis in the layer of granular cells, dissolution of the oocyte and nucleus of ovarian follicles. Finally, the female fertility was dramatically affected across generations with a reduced male\female ratio. Our data indicate that the exposure of pregnant female to TCDD has serious negative effects in the female productive system across generations and suggest the use of hormonal alternation as biomarker to monitor and assess the indirect exposure of these generations to TCDD.
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Affiliation(s)
- Nour Aldeli
- Department of Animal Biology, Faculty of Sciences, University of Damascus, Damascus, Syria
| | - Chadi Soukkarie
- Department of Animal Biology, Faculty of Sciences, University of Damascus, Damascus, Syria
| | - Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), Damascus, Syria.
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2
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Li J, Li Y, Sha R, Zheng L, Xu L, Xie HQ, Zhao B. Effects of perinatal TCDD exposure on colonic microbiota and metabolism in offspring and mother mice. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 832:154762. [PMID: 35364153 DOI: 10.1016/j.scitotenv.2022.154762] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 06/14/2023]
Abstract
Emerging evidence supports that exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) impacts the gut microbiota and metabolic pathways. TCDD can be transmitted from mother to child; thus, we hypothesize that maternal exposure to TCDD may affect the gut microbiota in mothers and offspring. To acquire in vivo evidence supporting this hypothesis, female C57BL/6 mice were administered with TCDD (0.1 and 10 μg/kg body weight (bw)) during pregnancy and lactation periods, and then changes of colonic microbiota in offspring and mothers were evaluated. High-throughput sequencing of the V4 regions of the 16S rRNA gene was performed. The composition and structure of the colonic microbiota in offspring and mothers were significantly influenced by 10 μg/kg bw TCDD as demonstrated by upregulation of harmful bacteria and downregulation of beneficial bacteria. Paradoxically, pathogenic bacteria and opportunistic pathogens were conversely decreased in the offspring of the low-dose TCDD treatment group. Tryptophan (Trp) metabolism exhibited a noticeable change caused by the alteration of colonic microbiota in offspring after maternal exposure to 10 μg/kg bw TCDD, which showed a linear dependence, demonstrating that pathogens or opportunistic pathogens may accelerate the dysbiosis of Trp metabolism. Trp metabolism dysregulation caused by the changed colonic microbiota may subsequently impact other intestinal segments or even living organisms. Our study provides new evidence indicating a potential influence of early TCDD exposure on the colonic microbiota and metabolism.
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Affiliation(s)
- Jiao Li
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunping Li
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; School of Environment, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
| | - Rui Sha
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Liping Zheng
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, Nanjing 210042, China
| | - Li Xu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Heidi Qunhui Xie
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bin Zhao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; School of Environment, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China.
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3
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Fling RR, Zacharewski TR. Aryl Hydrocarbon Receptor (AhR) Activation by 2,3,7,8-Tetrachlorodibenzo- p-Dioxin (TCDD) Dose-Dependently Shifts the Gut Microbiome Consistent with the Progression of Non-Alcoholic Fatty Liver Disease. Int J Mol Sci 2021; 22:12431. [PMID: 34830313 PMCID: PMC8625315 DOI: 10.3390/ijms222212431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 11/16/2021] [Accepted: 11/16/2021] [Indexed: 11/17/2022] Open
Abstract
Gut dysbiosis with disrupted enterohepatic bile acid metabolism is commonly associated with non-alcoholic fatty liver disease (NAFLD) and recapitulated in a NAFLD-phenotype elicited by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in mice. TCDD induces hepatic fat accumulation and increases levels of secondary bile acids, including taurolithocholic acid and deoxycholic acid (microbial modified bile acids involved in host bile acid regulation signaling pathways). To investigate the effects of TCDD on the gut microbiota, the cecum contents of male C57BL/6 mice orally gavaged with sesame oil vehicle or 0.3, 3, or 30 µg/kg TCDD were examined using shotgun metagenomic sequencing. Taxonomic analysis identified dose-dependent increases in Lactobacillus species (i.e., Lactobacillus reuteri). Increased species were also associated with dose-dependent increases in bile salt hydrolase sequences, responsible for deconjugation reactions in secondary bile acid metabolism. Increased L. reuteri levels were further associated with mevalonate-dependent isopentenyl diphosphate (IPP) biosynthesis and o-succinylbenzoate synthase, a menaquinone biosynthesis associated gene. Analysis of the gut microbiomes from cirrhosis patients identified an increased abundance of genes from the mevalonate-dependent IPP biosynthesis as well as several other menaquinone biosynthesis genes, including o-succinylbenzoate synthase. These results extend the association of lactobacilli with the AhR/intestinal axis in NAFLD progression and highlight the similarities between TCDD-elicited phenotypes in mice to human NAFLD.
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Affiliation(s)
- Russell R. Fling
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA;
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI 48824, USA
| | - Timothy R. Zacharewski
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
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4
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Chiu K, Warner G, Nowak RA, Flaws JA, Mei W. The Impact of Environmental Chemicals on the Gut Microbiome. Toxicol Sci 2021; 176:253-284. [PMID: 32392306 DOI: 10.1093/toxsci/kfaa065] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Since the surge of microbiome research in the last decade, many studies have provided insight into the causes and consequences of changes in the gut microbiota. Among the multiple factors involved in regulating the microbiome, exogenous factors such as diet and environmental chemicals have been shown to alter the gut microbiome significantly. Although diet substantially contributes to changes in the gut microbiome, environmental chemicals are major contaminants in our food and are often overlooked. Herein, we summarize the current knowledge on major classes of environmental chemicals (bisphenols, phthalates, persistent organic pollutants, heavy metals, and pesticides) and their impact on the gut microbiome, which includes alterations in microbial composition, gene expression, function, and health effects in the host. We then discuss health-related implications of gut microbial changes, which include changes in metabolism, immunity, and neurological function.
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Affiliation(s)
- Karen Chiu
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61802.,Division of Nutritional Sciences, College of Agricultural, Consumer, and Environmental Sciences
| | - Genoa Warner
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61802
| | - Romana A Nowak
- Carl R. Woese Institute for Genomic Biology.,Department of Animal Sciences, College of Agricultural, Consumer, and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Jodi A Flaws
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61802.,Division of Nutritional Sciences, College of Agricultural, Consumer, and Environmental Sciences.,Carl R. Woese Institute for Genomic Biology
| | - Wenyan Mei
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61802.,Carl R. Woese Institute for Genomic Biology
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5
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Tu YJ, Premachandra GS, Boyd SA, Sallach JB, Li H, Teppen BJ, Johnston CT. Synthesis and evaluation of Fe 3O 4-impregnated activated carbon for dioxin removal. CHEMOSPHERE 2021; 263:128263. [PMID: 33297207 PMCID: PMC7733032 DOI: 10.1016/j.chemosphere.2020.128263] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 08/19/2020] [Accepted: 09/02/2020] [Indexed: 06/12/2023]
Abstract
Polychlorinated dibenzo-p-dioxins and -furans (PCDD/PCDFs) are highly toxic organic pollutants in soils and sediments which persist over timescales that extend from decades to centuries. There is a growing need to develop effective technologies for remediating PCDD/Fs-contaminated soils and sediments to protect human and ecosystem health. The use of sorbent amendments to sequester PCDD/Fs has emerged as one promising technology. A synthesis method is described here to create a magnetic activated carbon composite (AC-Fe3O4) for dioxin removal and sampling that could be recovered from soils using magnetic separation. Six AC-Fe3O4 composites were evaluated (five granular ACs (GACs) and one fine-textured powder AC(PAC)) for their magnetization and ability to sequester dibenzo-p-dioxin (DD). Both GAC/PAC and GAC/PAC-Fe3O4 composites effectively removed DD from aqueous solution. The sorption affinity of DD for GAC-Fe3O4 was slightly reduced compared to GAC alone, which is attributed to the blocking of sorption sites. The magnetization of a GAC-Fe3O4 composite reached 5.38 emu/g based on SQUID results, allowing the adsorbent to be easily separated from aqueous solution using an external magnetic field. Similarly, a fine-textured PAC-Fe3O4 composite was synthesized with a magnetization of 9.3 emu/g.
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Affiliation(s)
- Yao-Jen Tu
- School of Environmental and Geographical Sciences, Shanghai Normal University, 100 Guilin Rd., Shanghai, 200234, China
| | | | - Stephen A Boyd
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA
| | - J Brett Sallach
- Department of Environment and Geography, University of York, Heslington, York, YO10 5NG, UK
| | - Hui Li
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA
| | - Brian J Teppen
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, 48824, USA
| | - Cliff T Johnston
- Department of Agronomy, Purdue University, 915 W. State Street, West Lafayette, IN, 47907, USA; Department of Earth, Atmospheric and Planetary Sciences, 550 Stadium Mall, Purdue University, West Lafayette, IN, 47907, USA.
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6
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Neamah WH, Busbee PB, Alghetaa H, Abdulla OA, Nagarkatti M, Nagarkatti P. AhR Activation Leads to Alterations in the Gut Microbiome with Consequent Effect on Induction of Myeloid Derived Suppressor Cells in a CXCR2-Dependent Manner. Int J Mol Sci 2020; 21:ijms21249613. [PMID: 33348596 PMCID: PMC7767008 DOI: 10.3390/ijms21249613] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 11/27/2020] [Accepted: 12/12/2020] [Indexed: 02/06/2023] Open
Abstract
Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a potent ligand for AhR and a known carcinogen. While AhR activation by TCDD leads to significant immunosuppression, how this translates into carcinogenic signal is unclear. Recently, we demonstrated that activation of AhR by TCDD in naïve C57BL6 mice leads to massive induction of myeloid derived-suppressor cells (MDSCs). In the current study, we investigated the role of the gut microbiota in TCDD-mediated MDSC induction. TCDD caused significant alterations in the gut microbiome, such as increases in Prevotella and Lactobacillus, while decreasing Sutterella and Bacteroides. Fecal transplants from TCDD-treated donor mice into antibiotic-treated mice induced MDSCs and increased regulatory T-cells (Tregs). Injecting TCDD directly into antibiotic-treated mice also induced MDSCs, although to a lesser extent. These data suggested that TCDD-induced dysbiosis plays a critical role in MDSC induction. Interestingly, treatment with TCDD led to induction of MDSCs in the colon and undetectable levels of cysteine. MDSCs suppressed T cell proliferation while reconstitution with cysteine restored this response. Lastly, blocking CXC chemokine receptor 2 (CXCR2) impeded TCDD-mediated MDSC induction. Our data demonstrate that AhR activation by TCDD triggers dysbiosis which, in turn, regulates, at least in part, induction of MDSCs.
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7
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Chiu K, Warner G, Nowak RA, Flaws JA, Mei W. The Impact of Environmental Chemicals on the Gut Microbiome. Toxicol Sci 2020. [PMID: 32392306 DOI: 10.1093/toxsci/kfaa1065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023] Open
Abstract
Since the surge of microbiome research in the last decade, many studies have provided insight into the causes and consequences of changes in the gut microbiota. Among the multiple factors involved in regulating the microbiome, exogenous factors such as diet and environmental chemicals have been shown to alter the gut microbiome significantly. Although diet substantially contributes to changes in the gut microbiome, environmental chemicals are major contaminants in our food and are often overlooked. Herein, we summarize the current knowledge on major classes of environmental chemicals (bisphenols, phthalates, persistent organic pollutants, heavy metals, and pesticides) and their impact on the gut microbiome, which includes alterations in microbial composition, gene expression, function, and health effects in the host. We then discuss health-related implications of gut microbial changes, which include changes in metabolism, immunity, and neurological function.
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Affiliation(s)
- Karen Chiu
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61802
- Division of Nutritional Sciences, College of Agricultural, Consumer, and Environmental Sciences
| | - Genoa Warner
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61802
| | - Romana A Nowak
- Carl R. Woese Institute for Genomic Biology
- Department of Animal Sciences, College of Agricultural, Consumer, and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | - Jodi A Flaws
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61802
- Division of Nutritional Sciences, College of Agricultural, Consumer, and Environmental Sciences
- Carl R. Woese Institute for Genomic Biology
| | - Wenyan Mei
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61802
- Carl R. Woese Institute for Genomic Biology
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8
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Sallach JB, Crawford R, Li H, Johnston CT, Teppen BJ, Kaminski NE, Boyd SA. Activated carbons of varying pore structure eliminate the bioavailability of 2,3,7,8-tetrachlorodibenzo-p-dioxin to a mammalian (mouse) model. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 650:2231-2238. [PMID: 30292116 DOI: 10.1016/j.scitotenv.2018.09.270] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 09/19/2018] [Accepted: 09/20/2018] [Indexed: 06/08/2023]
Abstract
The use of activated carbon (AC) as an in situ sorbent amendment to sequester polychlorinated-dibenzo-p-dioxins and furans (PCDD/Fs) present in contaminated soils and sediments has recently gained attention as a novel remedial approach. This remedy could be implemented at much lower cost while minimizing habitat destruction as compared to traditional remediation technologies that rely on dredging/excavation and landfilling. Several prior studies have demonstrated the ability of AC amendments to reduce pore water concentrations and hence bioaccumulation of PCDD/Fs in invertebrate species. However, our recent study was the first to show that AC had the ability to sequester 2,3,7,8‑tetrachlorodibenzo‑p‑dioxin (TCDD) in a form that eliminated bioavailability to a mammalian (mouse) model. Here we show that three commercially available ACs, representing a wide range of pore size distributions, were equally effective in eliminating the bioavailability of TCDD based upon two sensitive bioassays, hepatic induction of cyp1A1 mRNA and immunoglobulin M antibody-forming cell response. These results provide direct evidence that a wide range of structurally diverse commercially available ACs may be suitable for use as in situ sorbent amendments to provide a cost-effective remedy for PCDD/F contaminated soils and sediments. Potentially, adaption of this technology would minimize habitat destruction and be protective of ecosystem and human health.
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Affiliation(s)
- J Brett Sallach
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA.
| | - Robert Crawford
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI 48824, USA.
| | - Hui Li
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA.
| | - Cliff T Johnston
- Crop, Soil, and Environmental Science, Purdue University, West Lafayette, Indiana 47907, USA.
| | - Brian J Teppen
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA.
| | - Norbert E Kaminski
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI 48824, USA; Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA.
| | - Stephen A Boyd
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA.
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9
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Stedtfeld RD, Chai B, Crawford RB, Stedtfeld TM, Williams MR, Xiangwen S, Kuwahara T, Cole JR, Kaminski NE, Tiedje JM, Hashsham SA. Modulatory Influence of Segmented Filamentous Bacteria on Transcriptomic Response of Gnotobiotic Mice Exposed to TCDD. Front Microbiol 2017; 8:1708. [PMID: 28936204 PMCID: PMC5594080 DOI: 10.3389/fmicb.2017.01708] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Accepted: 08/23/2017] [Indexed: 12/17/2022] Open
Abstract
Environmental toxicants such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), an aryl hydrocarbon receptor (AhR), are known to induce host toxicity and structural shifts in the gut microbiota. Key bacterial populations with similar or opposing functional responses to AhR ligand exposure may potentially help regulate expression of genes associated with immune dysfunction. To examine this question and the mechanisms for AhR ligand-induced bacterial shifts, C57BL/6 gnotobiotic mice were colonized with and without segmented filamentous bacteria (SFB) – an immune activator. Mice were also colonized with polysaccharide A producing Bacteroides fragilis – an immune suppressor to serve as a commensal background. Following colonization, mice were administered TCDD (30 μg/kg) every 4 days for 28 days by oral gavage. Quantified with the nCounter® mouse immunology panel, opposing responses in ileal gene expression (e.g., genes associated with T-cell differentiation via the class II major histocompatibility complex) as a result of TCDD dosing and SFB colonization were observed. Genes that responded to TCDD in the presence of SFB did not show a significant response in the absence of SFB, and vice versa. Regulatory T-cells examined in the mesenteric lymph-nodes, spleen, and blood were also less impacted by TCDD in mice colonized with SFB. TCDD-induced shifts in abundance of SFB and B. fragilis compared with previous studies in mice with a traditional gut microbiome. With regard to the mouse model colonized with individual populations, results indicate that TCDD-induced host response was significantly modulated by the presence of SFB in the gut microbiome, providing insight into therapeutic potential between AhR ligands and key commensals.
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Affiliation(s)
- Robert D Stedtfeld
- Department of Civil and Environmental Engineering, East LansingMI, United States
| | - Benli Chai
- Center for Microbial Ecology, Michigan State University, East LansingMI, United States
| | - Robert B Crawford
- Institute for Integrative Toxicology, Michigan State University, East LansingMI, United States.,Department of Pharmacology and Toxicology, Michigan State University, East LansingMI, United States
| | - Tiffany M Stedtfeld
- Department of Civil and Environmental Engineering, East LansingMI, United States
| | - Maggie R Williams
- Department of Civil and Environmental Engineering, East LansingMI, United States
| | - Shao Xiangwen
- Department of Civil and Environmental Engineering, East LansingMI, United States
| | - Tomomi Kuwahara
- Department of Molecular Bacteriology, Institute of Health Biosciences, University of Tokushima Graduate SchoolTokushima, Japan
| | - James R Cole
- Center for Microbial Ecology, Michigan State University, East LansingMI, United States
| | - Norbert E Kaminski
- Institute for Integrative Toxicology, Michigan State University, East LansingMI, United States.,Department of Pharmacology and Toxicology, Michigan State University, East LansingMI, United States
| | - James M Tiedje
- Center for Microbial Ecology, Michigan State University, East LansingMI, United States
| | - Syed A Hashsham
- Department of Civil and Environmental Engineering, East LansingMI, United States.,Center for Microbial Ecology, Michigan State University, East LansingMI, United States
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