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Koh YC, Pan MH. Food-Borne Polycyclic Aromatic Hydrocarbons and Circadian Disruption. ACS OMEGA 2024; 9:31298-31312. [PMID: 39072055 PMCID: PMC11270680 DOI: 10.1021/acsomega.4c04120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 06/19/2024] [Accepted: 06/26/2024] [Indexed: 07/30/2024]
Abstract
Circadian disruption has been found to increase the risk of metabolic diseases, brain disorders, and cancer. The aryl hydrocarbon receptor (AhR), responsible for xenobiotic metabolism, is known to be activated by certain environmental stimuli, including polycyclic aromatic hydrocarbons (PAHs). Exposure to these stimuli may lead to diseases related to circadian disruption, with AhR activation suggested as a leading cause. Both the aryl hydrocarbon receptor nuclear translocator (ARNT) and aryl hydrocarbon receptor nuclear translocator-like (BMAL1) are class II basic helix-loop-helix/Per-ARNT-SIM (bHLH-PAS) proteins. These proteins form heterodimers with stimulated class I bHLH-PAS proteins, including circadian locomotor output cycles kaput (CLOCK) and AhR. Due to their sequential similarity, the overactivation of AhR by toxicants, such as PAHs, may lead to the formation of heterodimers with BMAL1, potentially causing circadian disruption. Dysregulation of BMAL1 can affect a wide range of metabolic genes, emphasizing its crucial roles. However, this issue has not been adequately addressed. Previous studies have reported that the inhibitory effects of phytochemicals on AhR activation can ameliorate diseases induced by environmental toxicants. Additionally, some phytochemicals have shown preventive effects on circadian misalignment. Therefore, this Review aims to explore potential strategies to prevent circadian disruption induced by food-borne toxicants, such as benzo[a]pyrene; to generate new ideas for future studies; and to highlight the importance of investigating these preventive strategies.
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Affiliation(s)
- Yen-Chun Koh
- Institute
of Food Science and Technology, National
Taiwan University, Taipei 106017, Taiwan
| | - Min-Hsiung Pan
- Institute
of Food Science and Technology, National
Taiwan University, Taipei 106017, Taiwan
- Department
of Medical Research, China Medical University Hospital, China Medical University, Taichung City 404327, Taiwan
- Department
of Health and Nutrition Biotechnology, Asia
University, Taichung City 413305, Taiwan
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2
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Salminen A. Aryl hydrocarbon receptor impairs circadian regulation in Alzheimer's disease: Potential impact on glymphatic system dysfunction. Eur J Neurosci 2024; 60:3901-3920. [PMID: 38924210 DOI: 10.1111/ejn.16450] [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: 01/17/2024] [Revised: 05/23/2024] [Accepted: 06/10/2024] [Indexed: 06/28/2024]
Abstract
Circadian clocks maintain diurnal rhythms of sleep-wake cycle of 24 h that regulate not only the metabolism of an organism but also many other periodical processes. There is substantial evidence that circadian regulation is impaired in Alzheimer's disease. Circadian clocks regulate many properties known to be disturbed in Alzheimer's patients, such as the integrity of the blood-brain barrier (BBB) as well as the diurnal glymphatic flow that controls waste clearance from the brain. Interestingly, an evolutionarily conserved transcription factor, that is, aryl hydrocarbon receptor (AhR), impairs the function of the core clock proteins and thus could disturb diurnal rhythmicity in the BBB. There is abundant evidence that the activation of AhR signalling inhibits the expression of the major core clock proteins, such as the brain and muscle arnt-like 1 (BMAL1), clock circadian regulator (CLOCK) and period circadian regulator 1 (PER1) in different experimental models. The expression of AhR is robustly increased in the brains of Alzheimer's patients, and protein level is enriched in astrocytes of the BBB. It seems that AhR signalling inhibits glymphatic flow since it is known that (i) activation of AhR impairs the function of the BBB, which is cooperatively interconnected with the glymphatic system in the brain, and (ii) neuroinflammation and dysbiosis of gut microbiota generate potent activators of AhR, which are able to impair glymphatic flow. I will examine current evidence indicating that activation of AhR signalling could disturb circadian functions of the BBB and impair glymphatic flow and thus be involved in the development of Alzheimer's pathology.
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Affiliation(s)
- Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
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3
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Andersen ME, Barutcu AR, Black MB, Harrill JA. Transcriptomic analysis of AHR wildtype and Knock-out rat livers supports TCDD's role in AHR/ARNT-mediated circadian disruption and hepatotoxicity. Toxicol Appl Pharmacol 2024; 487:116956. [PMID: 38735589 DOI: 10.1016/j.taap.2024.116956] [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: 03/15/2024] [Revised: 04/30/2024] [Accepted: 05/05/2024] [Indexed: 05/14/2024]
Abstract
Single, high doses of TCDD in rats are known to cause wasting, a progressive loss of 30 to 50% body weight and death within several weeks. To identify pathway perturbations at or near doses causing wasting, we examined differentially gene expression (DGE) and pathway enrichment in centrilobular (CL) and periportal (PP) regions of female rat livers following 6 dose levels of TCDD - 0, 3, 22, 100, 300, and 1000 ng/kg/day, 5 days/week for 4 weeks. At the higher doses, rats lost weight, had increased liver/body weight ratios and nearly complete cessation of liver cell proliferation, signs consistent with wasting. DGE curves were left shifted for the CL versus the PP regions. Canonical Phase I and Phase II genes were maximally increased at lower doses and remained elevated at all doses. At lower doses, ≤ 22 ng/kg/day in the CL and ≤ 100 ng/kg/day, upregulated genes showed transcription factor (TF) enrichment for AHR and ARNT. At the mid- and high-dose doses, there was a large number of downregulated genes and pathway enrichment for DEGs which showed downregulation of many cellular metabolism processes including those for steroids, fatty acid metabolism, pyruvate metabolism and citric acid cycle. There was significant TF enrichment of the hi-dose downregulated genes for RXR, ESR1, LXR, PPARalpha. At the highest dose, there was also pathway enrichment with upregulated genes for extracellular matrix organization, collagen formation, hemostasis and innate immune system. TCDD demonstrates most of its effects through binding the aryl hydrocarbon receptor (AHR) while the downregulation of metabolism genes at higher TCDD doses is known to be independent of AHR binding to DREs. Based on our results with DEG, we provide a hypothesis for wasting in which high doses of TCDD shift circadian processes away from the resting state, leading to greatly reduced synthesis of steroids and complex lipids needed for cell growth, and producing gene expression signals consistent with an epithelial-to-mesenchymal transition in hepatocytes.
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4
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Hoyeck MP, Angela Ching ME, Basu L, van Allen K, Palaniyandi J, Perera I, Poleo-Giordani E, Hanson AA, Ghorbani P, Fullerton MD, Bruin JE. The aryl hydrocarbon receptor in β-cells mediates the effects of TCDD on glucose homeostasis in mice. Mol Metab 2024; 81:101893. [PMID: 38309623 PMCID: PMC10867573 DOI: 10.1016/j.molmet.2024.101893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/24/2024] [Accepted: 01/30/2024] [Indexed: 02/05/2024] Open
Abstract
OBJECTIVE Chronic exposure to persistent organic pollutants (POPs) is associated with increased incidence of type 2 diabetes, hyperglycemia, and poor insulin secretion in humans. Dioxins and dioxin-like compounds are a broad class of POPs that exert cellular toxicity through activation of the aryl hydrocarbon receptor (AhR). We previously showed that a single high-dose injection of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, aka dioxin; 20 μg/kg) in vivo reduced fasted and glucose-stimulated plasma insulin levels for up to 6 weeks in male and female mice. TCDD-exposed male mice were also modestly hypoglycemic and had increased insulin sensitivity, whereas TCDD-exposed females were transiently glucose intolerant. Whether these effects are driven by AhR activation in β-cells requires investigation. METHODS We exposed female and male β-cell specific Ahr knockout (βAhrKO) mice and littermate Ins1-Cre genotype controls (βAhrWT) to a single high dose of 20 μg/kg TCDD and tracked the mice for 6 weeks. RESULTS Under baseline conditions, deleting AhR from β-cells caused hypoglycemia in female mice, increased insulin secretion ex vivo in female mouse islets, and promoted modest weight gain in male mice. Importantly, high-dose TCDD exposure impaired glucose homeostasis and β-cell function in βAhrWT mice, but these phenotypes were largely abolished in TCDD-exposed βAhrKO mice. CONCLUSION Our study demonstrates that AhR signaling in β-cells is important for regulating baseline β-cell function in female mice and energy homeostasis in male mice. We also show that β-cell AhR signaling largely mediates the effects of TCDD on glucose homeostasis in both sexes, suggesting that the effects of TCDD on β-cell function and health are driving metabolic phenotypes in peripheral tissues.
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Affiliation(s)
- Myriam P Hoyeck
- Department of Biology & Institute of Biochemistry, Carleton University, Ottawa, ON, Canada
| | - Ma Enrica Angela Ching
- Department of Biology & Institute of Biochemistry, Carleton University, Ottawa, ON, Canada
| | - Lahari Basu
- Department of Biology & Institute of Biochemistry, Carleton University, Ottawa, ON, Canada
| | - Kyle van Allen
- Department of Biology & Institute of Biochemistry, Carleton University, Ottawa, ON, Canada
| | - Jana Palaniyandi
- Department of Biology & Institute of Biochemistry, Carleton University, Ottawa, ON, Canada
| | - Ineli Perera
- Department of Biology & Institute of Biochemistry, Carleton University, Ottawa, ON, Canada
| | - Emilia Poleo-Giordani
- Department of Biology & Institute of Biochemistry, Carleton University, Ottawa, ON, Canada
| | - Antonio A Hanson
- Department of Biology & Institute of Biochemistry, Carleton University, Ottawa, ON, Canada
| | - Peyman Ghorbani
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, Centre for Infection, Immunity and Inflammation, Ottawa Institute of Systems Biology, Ottawa, ON, Canada
| | - Morgan D Fullerton
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, Centre for Infection, Immunity and Inflammation, Ottawa Institute of Systems Biology, Ottawa, ON, Canada; Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, ON, Canada
| | - Jennifer E Bruin
- Department of Biology & Institute of Biochemistry, Carleton University, Ottawa, ON, Canada.
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5
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Cholico GN, Fling RR, Sink WJ, Nault R, Zacharewski T. Inhibition of the urea cycle by the environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin increases serum ammonia levels in mice. J Biol Chem 2024; 300:105500. [PMID: 38013089 PMCID: PMC10731612 DOI: 10.1016/j.jbc.2023.105500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/26/2023] [Accepted: 11/18/2023] [Indexed: 11/29/2023] Open
Abstract
The aryl hydrocarbon receptor is a ligand-activated transcription factor known for mediating the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds. TCDD induces nonalcoholic fatty liver disease (NAFLD)-like pathologies including simple steatosis that can progress to steatohepatitis with fibrosis and bile duct proliferation in male mice. Dose-dependent progression of steatosis to steatohepatitis with fibrosis by TCDD has been associated with metabolic reprogramming, including the disruption of amino acid metabolism. Here, we used targeted metabolomic analysis to reveal dose-dependent changes in the level of ten serum and eleven hepatic amino acids in mice upon treatment with TCDD. Bulk RNA-seq and protein analysis showed TCDD repressed CPS1, OTS, ASS1, ASL, and GLUL, all of which are associated with the urea cycle and glutamine biosynthesis. Urea and glutamine are end products of the detoxification and excretion of ammonia, a toxic byproduct of amino acid catabolism. Furthermore, we found that the catalytic activity of OTC, a rate-limiting step in the urea cycle was also dose dependently repressed. These results are consistent with an increase in circulating ammonia. Collectively, the repression of the urea and glutamate-glutamine cycles increased circulating ammonia levels and the toxicity of TCDD.
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Affiliation(s)
- Giovan N Cholico
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Russell R Fling
- Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA; Microbiology & Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Warren J Sink
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Rance Nault
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Tim Zacharewski
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA.
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6
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Brooks TG, Manjrekar A, Mrcˇela A, Grant GR. Meta-analysis of Diurnal Transcriptomics in Mouse Liver Reveals Low Repeatability of Rhythm Analyses. J Biol Rhythms 2023; 38:556-570. [PMID: 37382061 PMCID: PMC10615793 DOI: 10.1177/07487304231179600] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
Abstract
To assess the consistency of biological rhythms across studies, 57 public mouse liver tissue timeseries totaling 1096 RNA-seq samples were obtained and analyzed. Only the control groups of each study were included, to create comparable data. Technical factors in RNA-seq library preparation were the largest contributors to transcriptome-level differences, beyond biological or experiment-specific factors such as lighting conditions. Core clock genes were remarkably consistent in phase across all studies. Overlap of genes identified as rhythmic across studies was generally low, with no pair of studies having over 60% overlap. Distributions of phases of significant genes were remarkably inconsistent across studies, but the genes that consistently identified as rhythmic had acrophase clustering near ZT0 and ZT12. Despite the discrepancies between single-study analyses, cross-study analyses found substantial consistency. Running compareRhythms on each pair of studies identified a median of only 11% of the identified rhythmic genes as rhythmic in only 1 of the 2 studies. Data were integrated across studies in a joint and individual variance estimate (JIVE) analysis, which showed that the top 2 components of joint within-study variation are determined by time of day. A shape-invariant model with random effects was fit to the genes to identify the underlying shape of the rhythms, consistent across all studies, including identifying 72 genes with consistently multiple peaks.
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Affiliation(s)
- Thomas G. Brooks
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Aditi Manjrekar
- Department of Neuroscience, The University of Texas at Dallas, Richardson, Texas
| | - Antonijo Mrcˇela
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Gregory R. Grant
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania
- Department of Genetics, University of Pennsylvania, Philadelphia, Pennsylvania
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7
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Barouki R, Samson M, Blanc EB, Colombo M, Zucman-Rossi J, Lazaridis KN, Miller GW, Coumoul X. The exposome and liver disease - how environmental factors affect liver health. J Hepatol 2023; 79:492-505. [PMID: 36889360 PMCID: PMC10448911 DOI: 10.1016/j.jhep.2023.02.034] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 02/14/2023] [Accepted: 02/15/2023] [Indexed: 03/10/2023]
Abstract
Since the initial development of the exposome concept, much effort has been devoted to the characterisation of the exposome through analytical, epidemiological, and toxicological/mechanistic studies. There is now an urgent need to link the exposome to human diseases and to include exposomics in the characterisation of environment-linked pathologies together with genomics and other omics. Liver diseases are particularly well suited for such studies since major functions of the liver include the detection, detoxification, and elimination of xenobiotics, as well as inflammatory responses. It is well known that several liver diseases are associated with i) addictive behaviours such as alcohol consumption, smoking, and to a certain extent dietary imbalance and obesity, ii) viral and parasitic infections, and iii) exposure to toxins and occupational chemicals. Recent studies indicate that environmental exposures are also significantly associated with liver diseases, and these include air pollution (particulate matter and volatile chemicals), contaminants such as polyaromatic hydrocarbons, bisphenol A and per-and poly-fluorinated substances, and physical stressors such as radiation. Furthermore, microbial metabolites and the "gut-liver" axis play a major role in liver diseases. Exposomics is poised to play a major role in the field of liver pathology. Methodological advances such as the exposomics-metabolomics framework, the determination of risk factors' genomic and epigenomic signatures, and cross-species biological pathway analysis should further delineate the impact of the exposome on the liver, opening the way for improved prevention, as well as the identification of new biomarkers of exposure and effects, and additional therapeutic targets.
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Affiliation(s)
| | - Michel Samson
- Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
| | | | - Massimo Colombo
- San Raffaele Hospital, Liver Center, Via Olgettina 60, 20132, Milan, Italy
| | - Jessica Zucman-Rossi
- Centre de Recherche des Cordeliers, Université Paris Cité, Sorbonne Université, Inserm, AP-HP, Hôpital Européen Georges Pompidou, Institut du Cancer Paris CARPEM, F-75006, Paris, France
| | | | - Gary W Miller
- Department of Environmental Health Sciences, Columbia University Mailman School of Public Health, New York, NY, 10032, USA
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8
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Wahlang B. RISING STARS: Sex differences in toxicant-associated fatty liver disease. J Endocrinol 2023; 258:e220247. [PMID: 37074385 PMCID: PMC10330380 DOI: 10.1530/joe-22-0247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 04/19/2023] [Indexed: 04/20/2023]
Abstract
Based on biological sex, the consequential health outcomes from exposures to environmental chemicals or toxicants can differ in disease pathophysiology, progression, and severity. Due to basal differences in cellular and molecular processes resulting from sexual dimorphism of organs including the liver and additional factors influencing 'gene-environment' interactions, males and females can exhibit different responses to toxicant exposures. Associations between environmental/occupational chemical exposures and fatty liver disease (FLD) have been well-acknowledged in human epidemiologic studies and their causal relationships demonstrated in experimental models. However, studies related to sex differences in liver toxicology are still limited to draw any inferences on sex-dependent chemical toxicity. The purpose of this review is to highlight the present state of knowledge on the existence of sex differences in toxicant-associated FLD (TAFLD), discuss potential underlying mechanisms driving these differences, implications of said differences on disease susceptibility, and emerging concepts. Chemicals of interest include various categories of pollutants that have been investigated in TAFLD, namely persistent organic pollutants, volatile organic compounds, and metals. Insight into research areas requiring further development is also discussed, with the objective of narrowing the knowledge gap on sex differences in environmental liver diseases. Major conclusions from this review exercise are that biological sex influences TAFLD risks, in part due to (i) toxicant disruption of growth hormone and estrogen receptor signaling, (ii) basal sex differences in energy mobilization and storage, and (iii) differences in chemical metabolism and subsequent body burden. Finally, further sex-dependent toxicological assessments are warranted for the development of sex-specific intervention strategies.
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Affiliation(s)
- Banrida Wahlang
- Division of Gastroenterology, Hepatology & Nutrition, Department of Medicine, School of Medicine, University of Louisville, Louisville, KY, 40202, USA
- UofL Superfund Research Center, University of Louisville, Louisville, KY, 40202, USA
- The Center for Integrative Environmental Health Sciences, University of Louisville, Louisville, KY, 40202, USA
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9
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Orlowska K, Fling RR, Nault R, Schilmiller AL, Zacharewski TR. Cystine/Glutamate Xc - Antiporter Induction Compensates for Transsulfuration Pathway Repression by 2,3,7,8-Tetrachlorodibenzo- p-dioxin (TCDD) to Ensure Cysteine for Hepatic Glutathione Biosynthesis. Chem Res Toxicol 2023; 36:900-915. [PMID: 37184393 PMCID: PMC10284067 DOI: 10.1021/acs.chemrestox.3c00017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Indexed: 05/16/2023]
Abstract
Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been associated with the induction of oxidative stress and the progression of steatosis to steatohepatitis with fibrosis. It also disrupts metabolic pathways including one-carbon metabolism (OCM) and the transsulfuration pathway with possible consequences on glutathione (GSH) levels. In this study, complementary RNAseq and metabolomics data were integrated to examine the hepatic transsulfuration pathway and glutathione biosynthesis in mice following treatment with TCDD every 4 days for 28 days. TCDD dose-dependently repressed hepatic cystathionine β-synthase (CBS) and cystathionine γ-lyase (CTH) mRNA and protein levels. Reduced CBS and CTH levels are also correlated with dose-dependent decreases in hepatic extract hydrogen sulfide (H2S). In contrast, cysteine levels increased consistent with the induction of Slc7a11, which encodes for the cystine/glutamate Xc- antiporter. Cotreatment of primary hepatocytes with sulfasalazine, a cystine/glutamate Xc- antiporter inhibitor, decreased labeled cysteine incorporation into GSH with a corresponding increase in TCDD cytotoxicity. Although reduced and oxidized GSH levels were unchanged following treatment due to the induction of GSH/GSSG efflux transporter by TCDD, the GSH:GSSG ratio decreased and global protein S-glutathionylation levels in liver extracts increased in response to oxidative stress along with the induction of glutamate-cysteine ligase catalytic subunit (Gclc), glutathione synthetase (Gss), glutathione disulfide reductase (Gsr), and glutathione transferase π (Gstp). Furthermore, levels of ophthalmic acid, a biomarker of oxidative stress indicating GSH consumption, were also increased. Collectively, the data suggest that increased cystine transport due to cystine/glutamate Xc- antiporter induction compensated for decreased cysteine production following repression of the transsulfuration pathway to support GSH synthesis in response to TCDD-induced oxidative stress.
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Affiliation(s)
- Karina Orlowska
- Biochemistry
& Molecular Biology, Institute for Integrative Toxicology, Microbiology &
Molecular Genetics, and Mass Spectrometry and Metabolomics Core, Michigan State University, East Lansing, Michigan 48824, United States
| | - Russ R. Fling
- Biochemistry
& Molecular Biology, Institute for Integrative Toxicology, Microbiology &
Molecular Genetics, and Mass Spectrometry and Metabolomics Core, Michigan State University, East Lansing, Michigan 48824, United States
| | - Rance Nault
- Biochemistry
& Molecular Biology, Institute for Integrative Toxicology, Microbiology &
Molecular Genetics, and Mass Spectrometry and Metabolomics Core, Michigan State University, East Lansing, Michigan 48824, United States
| | - Anthony L. Schilmiller
- Biochemistry
& Molecular Biology, Institute for Integrative Toxicology, Microbiology &
Molecular Genetics, and Mass Spectrometry and Metabolomics Core, Michigan State University, East Lansing, Michigan 48824, United States
| | - Timothy R. Zacharewski
- Biochemistry
& Molecular Biology, Institute for Integrative Toxicology, Microbiology &
Molecular Genetics, and Mass Spectrometry and Metabolomics Core, Michigan State University, East Lansing, Michigan 48824, United States
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10
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Patel TD, Nakka M, Grimm SL, Coarfa C, Gorelick DA. Functional genomic analysis of non-canonical DNA regulatory elements of the aryl hydrocarbon receptor. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.01.538985. [PMID: 37205451 PMCID: PMC10187216 DOI: 10.1101/2023.05.01.538985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The aryl hydrocarbon receptor (AHR) is a ligand-dependent transcription factor that binds DNA and regulates genes in response to halogenated and polycyclic aromatic hydrocarbons. AHR also regulates the development and function of the liver and the immune system. In the canonical pathway, AHR binds a consensus DNA sequence, termed the xenobiotic response element (XRE), recruits protein coregulators, and regulates target gene expression. Emerging evidence suggests that AHR may regulate gene expression via an additional pathway, by binding to a non-consensus DNA sequence termed the non-consensus XRE (NC-XRE). The prevalence of NC-XRE motifs in the genome is not known. Studies using chromatin immunoprecipitation and reporter genes provide indirect evidence of AHR-NC-XRE interactions, but direct evidence for an AHR-NCXRE interaction that regulates transcription in a natural genomic context is lacking. Here, we analyzed AHR binding to NC-XRE DNA on a genome-wide scale in mouse liver. We integrated ChIP-seq and RNA-seq data and identified putative AHR target genes with NC-XRE motifs in regulatory regions. We also performed functional genomics at a single locus, the mouse Serpine1 gene. Deleting NC-XRE motifs from the Serpine1 promoter reduced the upregulation of Serpine1 by TCDD, an AHR ligand. We conclude that AHR upregulates Serpine1 via NC-XRE DNA. NC-XRE motifs are prevalent throughout regions of the genome where AHR binds. Taken together, our results suggest that AHR regulates genes via NC-XRE motifs. Our results will also improve our ability to identify AHR target genes and their physiologic relevance.
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Affiliation(s)
- Tajhal D Patel
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas, USA
| | - Manjula Nakka
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, Texas, USA
| | - Sandra L Grimm
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, Texas, USA
- Department of Molecular & Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas, USA
| | - Cristian Coarfa
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, Texas, USA
- Department of Molecular & Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, Texas, USA
| | - Daniel A Gorelick
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, Texas, USA
- Department of Molecular & Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
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11
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Salminen A. Aryl hydrocarbon receptor (AhR) impairs circadian regulation: impact on the aging process. Ageing Res Rev 2023; 87:101928. [PMID: 37031728 DOI: 10.1016/j.arr.2023.101928] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/23/2023] [Accepted: 04/06/2023] [Indexed: 04/11/2023]
Abstract
Circadian clocks control the internal sleep-wake rhythmicity of 24hours which is synchronized by the solar cycle. Circadian regulation of metabolism evolved about 2.5 billion years ago, i.e., the rhythmicity has been conserved from cyanobacteria and Archaea through to mammals although the mechanisms utilized have developed with evolution. While the aryl hydrocarbon receptor (AhR) is an evolutionarily conserved defence mechanism against environmental threats, it has gained many novel functions during evolution, such as the regulation of cell cycle, proteostasis, and many immune functions. There is robust evidence that AhR signaling impairs circadian rhythmicity, e.g., by interacting with the core BMAL1/CLOCK complex and disturbing the epigenetic regulation of clock genes. The maintenance of circadian rhythms is impaired with aging, disturbing metabolism and many important functions in aged organisms. Interestingly, it is known that AhR signaling promotes an age-related tissue degeneration, e.g., it is able to inhibit autophagy, enhance cellular senescence, and disrupt extracellular matrix. These alterations are rather similar to those induced by a long-term impairment of circadian rhythms. However, it is not known whether AhR signaling enhances the aging process by impairing circadian homeostasis. I will examine the experimental evidence indicating that AhR signaling is able to promote the age-related degeneration via a disruption of circadian rhythmicity.
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Affiliation(s)
- Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland.
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12
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Cholico GN, Orlowska K, Fling RR, Sink WJ, Zacharewski NA, Fader KA, Nault R, Zacharewski T. Consequences of reprogramming acetyl-CoA metabolism by 2,3,7,8-tetrachlorodibenzo-p-dioxin in the mouse liver. Sci Rep 2023; 13:4138. [PMID: 36914879 PMCID: PMC10011583 DOI: 10.1038/s41598-023-31087-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 03/06/2023] [Indexed: 03/14/2023] Open
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a persistent environmental contaminant that induces the progression of steatosis to steatohepatitis with fibrosis in mice. Furthermore, TCDD reprograms hepatic metabolism by redirecting glycolytic intermediates while inhibiting lipid metabolism. Here, we examined the effect of TCDD on hepatic acetyl-coenzyme A (acetyl-CoA) and β-hydroxybutyrate levels as well as protein acetylation and β-hydroxybutyrylation. Acetyl-CoA is not only a central metabolite in multiple anabolic and catabolic pathways, but also a substrate used for posttranslational modification of proteins and a surrogate indicator of cellular energy status. Targeted metabolomic analysis revealed a dose-dependent decrease in hepatic acetyl-CoA levels coincident with the phosphorylation of pyruvate dehydrogenase (E1), and the induction of pyruvate dehydrogenase kinase 4 and pyruvate dehydrogenase phosphatase, while repressing ATP citrate lyase and short-chain acyl-CoA synthetase gene expression. In addition, TCDD dose-dependently reduced the levels of hepatic β-hydroxybutyrate and repressed ketone body biosynthesis gene expression. Moreover, levels of total hepatic protein acetylation and β-hydroxybutyrylation were reduced. AMPK phosphorylation was induced consistent with acetyl-CoA serving as a cellular energy status surrogate, yet subsequent targets associated with re-establishing energy homeostasis were not activated. Collectively, TCDD reduced hepatic acetyl-CoA and β-hydroxybutyrate levels eliciting starvation-like conditions despite normal levels of food intake.
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Affiliation(s)
- Giovan N Cholico
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Karina Orlowska
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Russell R Fling
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
- Microbiology & Molecular Genetics, Michigan State University, East Lansing, MI, 48824, USA
| | - Warren J Sink
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Nicholas A Zacharewski
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
| | - Kelly A Fader
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Rance Nault
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Tim Zacharewski
- Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA.
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA.
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13
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Salminen A. Activation of aryl hydrocarbon receptor (AhR) in Alzheimer's disease: role of tryptophan metabolites generated by gut host-microbiota. J Mol Med (Berl) 2023; 101:201-222. [PMID: 36757399 PMCID: PMC10036442 DOI: 10.1007/s00109-023-02289-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 12/19/2022] [Accepted: 01/17/2023] [Indexed: 02/10/2023]
Abstract
Gut microbiota in interaction with intestinal host tissues influences many brain functions and microbial dysbiosis has been linked with brain disorders, such as neuropsychiatric conditions and Alzheimer's disease (AD). L-tryptophan metabolites and short-chained fatty acids (SCFA) are major messengers in the microbiota-brain axis. Aryl hydrocarbon receptors (AhR) are main targets of tryptophan metabolites in brain microvessels which possess an enriched expression of AhR protein. The Ah receptor is an evolutionarily conserved, ligand-activated transcription factor which is not only a sensor of xenobiotic toxins but also a pleiotropic regulator of both developmental processes and age-related tissue degeneration. Major microbiota-produced tryptophan metabolites involve indole derivatives, e.g., indole 3-pyruvic acid, indole 3-acetaldehyde, and indoxyl sulfate, whereas indoleamine and tryptophan 2,3-dioxygenases (IDO/TDO) of intestine host cells activate the kynurenine (KYN) pathway generating KYN metabolites, many of which are activators of AhR signaling. Chronic kidney disease (CKD) increases the serum level of indoxyl sulfate which promotes AD pathogenesis, e.g., it disrupts integrity of blood-brain barrier (BBB) and impairs cognitive functions. Activation of AhR signaling disturbs vascular homeostasis in brain; (i) it controls blood flow via the renin-angiotensin system, (ii) it inactivates endothelial nitric oxide synthase (eNOS), thus impairing NO production and vasodilatation, and (iii) it induces oxidative stress, stimulates inflammation, promotes cellular senescence, and enhances calcification of vascular walls. All these alterations are evident in cerebral amyloid angiopathy (CAA) in AD pathology. Moreover, AhR signaling can disturb circadian regulation and probably affect glymphatic flow. It seems plausible that dysbiosis of gut microbiota impairs the integrity of BBB via the activation of AhR signaling and thus aggravates AD pathology. KEY MESSAGES: Dysbiosis of gut microbiota is associated with dementia and Alzheimer's disease. Tryptophan metabolites are major messengers from the gut host-microbiota to brain. Tryptophan metabolites activate aryl hydrocarbon receptor (AhR) signaling in brain. The expression of AhR protein is enriched in brain microvessels and blood-brain barrier. Tryptophan metabolites disturb brain vascular integrity via AhR signaling. Dysbiosis of gut microbiota promotes inflammation and AD pathology via AhR signaling.
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Affiliation(s)
- Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, Kuopio, 70211, Finland.
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14
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Obodo D, Outland EH, Hughey JJ. Sex Inclusion in Transcriptome Studies of Daily Rhythms. J Biol Rhythms 2023; 38:3-14. [PMID: 36419398 PMCID: PMC9903005 DOI: 10.1177/07487304221134160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Biomedical research on mammals has traditionally neglected females, raising the concern that some scientific findings may generalize poorly to half the population. Although this lack of sex inclusion has been broadly documented, its extent within circadian genomics remains undescribed. To address this gap, we examined sex inclusion practices in a comprehensive collection of publicly available transcriptome studies on daily rhythms. Among 148 studies having samples from mammals in vivo, we found strong underrepresentation of females across organisms and tissues. Overall, only 23 of 123 studies in mice, 0 of 10 studies in rats, and 9 of 15 studies in humans included samples from females. In addition, studies having samples from both sexes tended to have more samples from males than from females. These trends appear to have changed little over time, including since 2016, when the US National Institutes of Health began requiring investigators to consider sex as a biological variable. Our findings highlight an opportunity to dramatically improve representation of females in circadian research and to explore sex differences in daily rhythms at the genome level.
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Affiliation(s)
- Dora Obodo
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee,Program in Chemical and Physical Biology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Elliot H. Outland
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jacob J. Hughey
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee,Program in Chemical and Physical Biology, Vanderbilt University School of Medicine, Nashville, Tennessee,Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee,Jacob J. Hughey, Department of Biomedical Informatics, Vanderbilt University Medical Center, 2525 West End Ave., Suite 1475, Nashville, TN 37232, USA; e-mail:
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15
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Nault R, Saha S, Bhattacharya S, Sinha S, Maiti T, Zacharewski T. Single-cell transcriptomics shows dose-dependent disruption of hepatic zonation by TCDD in mice. Toxicol Sci 2023; 191:135-148. [PMID: 36222588 PMCID: PMC9887712 DOI: 10.1093/toxsci/kfac109] [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: 02/03/2023] Open
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) dose-dependently induces the development of hepatic fat accumulation and inflammation with fibrosis in mice initially in the portal region. Conversely, differential gene and protein expression is first detected in the central region. To further investigate cell-specific and spatially resolved dose-dependent changes in gene expression elicited by TCDD, single-nuclei RNA sequencing and spatial transcriptomics were used for livers of male mice gavaged with TCDD every 4 days for 28 days. The proportion of 11 cell (sub)types across 131 613 nuclei dose-dependently changed with 68% of all portal and central hepatocyte nuclei in control mice being overtaken by macrophages following TCDD treatment. We identified 368 (portal fibroblasts) to 1339 (macrophages) differentially expressed genes. Spatial analyses revealed initial loss of portal identity that eventually spanned the entire liver lobule with increasing dose. Induction of R-spondin 3 (Rspo3) and pericentral Apc, suggested dysregulation of the Wnt/β-catenin signaling cascade in zonally resolved steatosis. Collectively, the integrated results suggest disruption of zonation contributes to the pattern of TCDD-elicited NAFLD pathologies.
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Affiliation(s)
- Rance Nault
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan 48824, USA
| | - Satabdi Saha
- Department of Statistics and Probability, Michigan State University, East Lansing, Michigan 48824, USA
| | - Sudin Bhattacharya
- Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan 48824, USA
- Biomedical Engineering Department, Pharmacology & Toxicology, Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan 48824, USA
| | - Samiran Sinha
- Department of Statistics, Texas A&M University, College Station, Texas 77840, USA
| | - Tapabrata Maiti
- Department of Statistics and Probability, Michigan State University, East Lansing, Michigan 48824, USA
| | - Tim Zacharewski
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan 48824, USA
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16
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Khazaal AQ, Haque N, Krager CR, Krager SL, Chambers C, Wilber A, Tischkau SA. Aryl hydrocarbon receptor affects circadian-regulated lipolysis through an E-Box-dependent mechanism. Mol Cell Endocrinol 2023; 559:111809. [PMID: 36283500 PMCID: PMC10509633 DOI: 10.1016/j.mce.2022.111809] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/17/2022] [Accepted: 10/19/2022] [Indexed: 11/06/2022]
Abstract
An internal circadian clock regulates timing of systemic energy homeostasis. The central clock in the hypothalamic suprachiasmatic nucleus (SCN) directs local clocks in peripheral tissues such as liver, muscle, and adipose tissue to synchronize metabolism with food intake and rest/activity cycles. Aryl hydrocarbon receptor (AhR) interacts with the molecular circadian clockworks. Activation of AhR dampens rhythmic expression of core clock genes, which may lead to metabolic dysfunction. Given the importance of appropriately-timed adipose tissue function to regulation of energy homeostasis, this study focused on mechanisms by which AhR may influence clock-controlled adipose tissue activity. We hypothesized that AhR activation in adipose tissue would impair lipolysis by dampening adipose rhythms, leading to a decreased lipolysis rate during fasting, and subsequently, altered serum glucose concentrations. Levels of clock gene and lipolysis gene transcripts in mouse mesenchymal stem cells (BMSCs) differentiated into mature adipocytes were suppressed by the AhR agonist β-napthoflavone (BNF), in an AhR dependent manner. BNF altered rhythms of core clock gene and lipolysis gene transcripts in C57bl6/J mice. BNF reduced serum free fatty acids, glycerol and liver glycogen. Chromatin immunoprecipitation indicated that BNF increased binding of AhR to E-Box elements in clock gene and lipolysis gene promoters. These data establish a link between AhR activation and impaired lipolysis, specifically by altering adipose tissue rhythmicity. In response to the decreased available energy from impaired lipolysis, the body increases glycogenolysis, thereby degrading more glycogen to provide necessary energy.
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Affiliation(s)
- Ali Qasim Khazaal
- Biotechnology Department, College of Science, University of Baghdad, Baghdad, Iraq; Department of Medical Microbiology, Immunology, and Cell Biology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Nazmul Haque
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Callie R Krager
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Stacey L Krager
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Christopher Chambers
- Department of Medical Microbiology, Immunology, and Cell Biology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Andrew Wilber
- Department of Medical Microbiology, Immunology, and Cell Biology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Shelley A Tischkau
- Department of Medical Microbiology, Immunology, and Cell Biology, Southern Illinois University School of Medicine, Springfield, IL, USA; Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL, USA.
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17
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Bernal K, Touma C, Erradhouani C, Boronat-Belda T, Gaillard L, Al Kassir S, Le Mentec H, Martin-Chouly C, Podechard N, Lagadic-Gossmann D, Langouet S, Brion F, Knoll-Gellida A, Babin PJ, Sovadinova I, Babica P, Andreau K, Barouki R, Vondracek J, Alonso-Magdalena P, Blanc E, Kim MJ, Coumoul X. Combinatorial pathway disruption is a powerful approach to delineate metabolic impacts of endocrine disruptors. FEBS Lett 2022; 596:3107-3123. [PMID: 35957500 DOI: 10.1002/1873-3468.14465] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 07/22/2022] [Accepted: 07/25/2022] [Indexed: 01/14/2023]
Abstract
The prevalence of metabolic diseases, such as obesity, diabetes, metabolic syndrome and chronic liver diseases among others, has been rising for several years. Epidemiology and mechanistic (in vivo, in vitro and in silico) toxicology have recently provided compelling evidence implicating the chemical environment in the pathogenesis of these diseases. In this review, we will describe the biological processes that contribute to the development of metabolic diseases targeted by metabolic disruptors, and will propose an integrated pathophysiological vision of their effects on several organs. With regard to these pathomechanisms, we will discuss the needs, and the stakes of evolving the testing and assessment of endocrine disruptors to improve the prevention and management of metabolic diseases that have become a global epidemic since the end of last century.
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Affiliation(s)
- Kévin Bernal
- INSERM UMR-S 1124, Paris, France.,Université Paris Cité, France
| | - Charbel Touma
- Inserm, EHESP, Irset (Institut de recherche en santé environnement et travail) - UMR_S 1085, Université Rennes, France
| | - Chedi Erradhouani
- Université Paris Cité, France.,Ecotoxicologie des substances et des milieux, Parc ALATA, INERIS, Verneuil-en-Halatte, France
| | - Talía Boronat-Belda
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universitas Miguel Hernández, Elche, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | - Lucas Gaillard
- INSERM UMR-S 1124, Paris, France.,Université Paris Cité, France
| | - Sara Al Kassir
- Department of Life and Health Sciences, INSERM U1211, MRGM, University of Bordeaux, Pessac, France
| | - Hélène Le Mentec
- Inserm, EHESP, Irset (Institut de recherche en santé environnement et travail) - UMR_S 1085, Université Rennes, France
| | - Corinne Martin-Chouly
- Inserm, EHESP, Irset (Institut de recherche en santé environnement et travail) - UMR_S 1085, Université Rennes, France
| | - Normand Podechard
- Inserm, EHESP, Irset (Institut de recherche en santé environnement et travail) - UMR_S 1085, Université Rennes, France
| | - Dominique Lagadic-Gossmann
- Inserm, EHESP, Irset (Institut de recherche en santé environnement et travail) - UMR_S 1085, Université Rennes, France
| | - Sophie Langouet
- Inserm, EHESP, Irset (Institut de recherche en santé environnement et travail) - UMR_S 1085, Université Rennes, France
| | - François Brion
- Ecotoxicologie des substances et des milieux, Parc ALATA, INERIS, Verneuil-en-Halatte, France
| | - Anja Knoll-Gellida
- Department of Life and Health Sciences, INSERM U1211, MRGM, University of Bordeaux, Pessac, France
| | - Patrick J Babin
- Department of Life and Health Sciences, INSERM U1211, MRGM, University of Bordeaux, Pessac, France
| | - Iva Sovadinova
- RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Pavel Babica
- RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Karine Andreau
- INSERM UMR-S 1124, Paris, France.,Université Paris Cité, France
| | - Robert Barouki
- INSERM UMR-S 1124, Paris, France.,Université Paris Cité, France
| | - Jan Vondracek
- Institute of Biophysics of the Czech Academy of Sciences, Brno, Czech Republic
| | - Paloma Alonso-Magdalena
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universitas Miguel Hernández, Elche, Spain.,Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | - Etienne Blanc
- INSERM UMR-S 1124, Paris, France.,Université Paris Cité, France
| | - Min Ji Kim
- INSERM UMR-S 1124, Paris, France.,Université Sorbonne Paris Nord, Bobigny, France
| | - Xavier Coumoul
- INSERM UMR-S 1124, Paris, France.,Université Paris Cité, France
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18
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Orlowska K, Fling RR, Nault R, Sink WJ, Schilmiller AL, Zacharewski T. Dioxin-elicited decrease in cobalamin redirects propionyl-CoA metabolism to the β-oxidation-like pathway resulting in acrylyl-CoA conjugate buildup. J Biol Chem 2022; 298:102301. [PMID: 35931118 PMCID: PMC9418907 DOI: 10.1016/j.jbc.2022.102301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 11/30/2022] Open
Abstract
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a persistent environmental contaminant that induces diverse biological and toxic effects, including reprogramming intermediate metabolism, mediated by the aryl hydrocarbon receptor. However, the specific reprogramming effects of TCDD are unclear. Here, we performed targeted LC-MS analysis of hepatic extracts from mice gavaged with TCDD. We detected an increase in S-(2-carboxyethyl)-L-cysteine, a conjugate from the spontaneous reaction between the cysteine sulfhydryl group and highly reactive acrylyl-CoA, an intermediate in the cobalamin (Cbl)-independent β-oxidation-like metabolism of propionyl-CoA. TCDD repressed genes in both the canonical Cbl-dependent carboxylase and the alternate Cbl-independent β-oxidation-like pathways as well as inhibited methylmalonyl-CoA mutase (MUT) at lower doses. Moreover, TCDD decreased serum Cbl levels and hepatic cobalt levels while eliciting negligible effects on gene expression associated with Cbl absorption, transport, trafficking, or derivatization to 5'-deoxy-adenosylcobalamin (AdoCbl), the required MUT cofactor. Additionally, TCDD induced the gene encoding aconitate decarboxylase 1 (Acod1), the enzyme responsible for decarboxylation of cis-aconitate to itaconate, and dose-dependently increased itaconate levels in hepatic extracts. Our results indicate MUT inhibition is consistent with itaconate activation to itaconyl-CoA, a MUT suicide inactivator that forms an adduct with adenosylcobalamin. This adduct in turn inhibits MUT activity and reduces Cbl levels. Collectively, these results suggest the decrease in MUT activity is due to Cbl depletion following TCDD treatment, which redirects propionyl-CoA metabolism to the alternate Cbl-independent β-oxidation-like pathway. The resulting hepatic accumulation of acrylyl-CoA likely contributes to TCDD-elicited hepatotoxicity and the multihit progression of steatosis to steatohepatitis with fibrosis.
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Affiliation(s)
- Karina Orlowska
- Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan, USA,Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Russ R. Fling
- Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA,Microbiology & Molecular Genetics, Michigan Sptate University, East Lansing, Michigan, USA
| | - Rance Nault
- Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan, USA,Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Warren J. Sink
- Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan, USA,Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Anthony L. Schilmiller
- Mass Spectrometry and Metabolomics Core, Michigan State University, East Lansing, Michigan, USA
| | - Tim Zacharewski
- Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA.
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19
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Mihelakis M, Ndikung J, Oelgeschläger M, Ertych N. The 4th dimension of in vitro systems - Time to level up. ENVIRONMENT INTERNATIONAL 2022; 164:107256. [PMID: 35472563 DOI: 10.1016/j.envint.2022.107256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 03/30/2022] [Accepted: 04/19/2022] [Indexed: 06/14/2023]
Abstract
Various in vitro model systems have been established over the last decades to understand physiological processes, the causalities of diseases and the response of humans to environmental and industrial chemicals or therapeutic drugs. Common to all is a limited biological significance due to the impairment of functionality, for instance by the lack of physiological 3D tissue architecture or the loss of fundamental regulatory mechanisms including the circadian rhythm. The circadian rhythm is an adaption of living organisms to rhythmic environmental changes of the day-night cycle and coordinates behavior as well as various crucial physiological processes in a 24-hour pattern. Here, we discuss the impact of integrating circadian regulation in experimental approaches and toxicological assessments to improve the biological relevance of the obtained results. In particular, it is known for some time that an ongoing disruption of the circadian rhythmicity is associated with an increased risk for cardiovascular disease, metabolic dysfunction or cancer. In the context of health recovery, the importance of circadian control mechanism is recognized by chronopharmacological concepts to increase the efficiency of pharmacological treatment strategies. Despite the undeniable circadian dependency and the biological relevance of manifold cellular and molecular processes, the impact of circadian regulation is hardly considered in a wide range of biomedical and toxicological research areas. Reactivating the circadian regulation holds the promise to enhance the biological relevance and reliability of in vitro approaches. In the context of human health protection the implementation of a circadian regulation will subsequently generate advanced physiologically relevant in vitro approaches and allows an improved toxicological assessment of health risks. In addition, the establishment of circadian disruption as a novel toxicological endpoint will provide a better understanding of toxicological mode of actions of environmental and industrial chemicals or drugs and enlarge the knowledge of disease development.
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Affiliation(s)
- Melina Mihelakis
- German Federal Institute for Risk Assessment, German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277 Berlin, Germany
| | - Johanna Ndikung
- German Federal Institute for Risk Assessment, German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277 Berlin, Germany
| | - Michael Oelgeschläger
- German Federal Institute for Risk Assessment, German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277 Berlin, Germany
| | - Norman Ertych
- German Federal Institute for Risk Assessment, German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277 Berlin, Germany.
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20
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Heindel JJ, Howard S, Agay-Shay K, Arrebola JP, Audouze K, Babin PJ, Barouki R, Bansal A, Blanc E, Cave MC, Chatterjee S, Chevalier N, Choudhury M, Collier D, Connolly L, Coumoul X, Garruti G, Gilbertson M, Hoepner LA, Holloway AC, Howell G, Kassotis CD, Kay MK, Kim MJ, Lagadic-Gossmann D, Langouet S, Legrand A, Li Z, Le Mentec H, Lind L, Monica Lind P, Lustig RH, Martin-Chouly C, Munic Kos V, Podechard N, Roepke TA, Sargis RM, Starling A, Tomlinson CR, Touma C, Vondracek J, Vom Saal F, Blumberg B. Obesity II: Establishing causal links between chemical exposures and obesity. Biochem Pharmacol 2022; 199:115015. [PMID: 35395240 PMCID: PMC9124454 DOI: 10.1016/j.bcp.2022.115015] [Citation(s) in RCA: 60] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 03/12/2022] [Accepted: 03/15/2022] [Indexed: 02/06/2023]
Abstract
Obesity is a multifactorial disease with both genetic and environmental components. The prevailing view is that obesity results from an imbalance between energy intake and expenditure caused by overeating and insufficient exercise. We describe another environmental element that can alter the balance between energy intake and energy expenditure: obesogens. Obesogens are a subset of environmental chemicals that act as endocrine disruptors affecting metabolic endpoints. The obesogen hypothesis posits that exposure to endocrine disruptors and other chemicals can alter the development and function of the adipose tissue, liver, pancreas, gastrointestinal tract, and brain, thus changing the set point for control of metabolism. Obesogens can determine how much food is needed to maintain homeostasis and thereby increase the susceptibility to obesity. The most sensitive time for obesogen action is in utero and early childhood, in part via epigenetic programming that can be transmitted to future generations. This review explores the evidence supporting the obesogen hypothesis and highlights knowledge gaps that have prevented widespread acceptance as a contributor to the obesity pandemic. Critically, the obesogen hypothesis changes the narrative from curing obesity to preventing obesity.
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Affiliation(s)
- Jerrold J Heindel
- Healthy Environment and Endocrine Disruptor Strategies, Commonweal, Bolinas, CA 92924, USA.
| | - Sarah Howard
- Healthy Environment and Endocrine Disruptor Strategies, Commonweal, Bolinas, CA 92924, USA
| | - Keren Agay-Shay
- Health and Environment Research (HER) Lab, The Azrieli Faculty of Medicine, Bar Ilan University, Israel
| | - Juan P Arrebola
- Department of Preventive Medicine and Public Health University of Granada, Granada, Spain
| | - Karine Audouze
- Department of Systems Biology and Bioinformatics, University of Paris, INSERM, T3S, Paris France
| | - Patrick J Babin
- Department of Life and Health Sciences, University of Bordeaux, INSERM, Pessac France
| | - Robert Barouki
- Department of Biochemistry, University of Paris, INSERM, T3S, 75006 Paris, France
| | - Amita Bansal
- College of Health & Medicine, Australian National University, Canberra, Australia
| | - Etienne Blanc
- Department of Biochemistry, University of Paris, INSERM, T3S, 75006 Paris, France
| | - Matthew C Cave
- Division of Gastroenterology, Hepatology and Nutrition, University of Louisville, Louisville, KY 40402, USA
| | - Saurabh Chatterjee
- Environmental Health and Disease Laboratory, University of South Carolina, Columbia, SC 29208, USA
| | - Nicolas Chevalier
- Obstetrics and Gynecology, University of Cote d'Azur, Cote d'Azur, France
| | - Mahua Choudhury
- College of Pharmacy, Texas A&M University, College Station, TX 77843, USA
| | - David Collier
- Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Lisa Connolly
- The Institute for Global Food Security, School of Biological Sciences, Queen's University, Belfast, Northern Ireland, UK
| | - Xavier Coumoul
- Department of Biochemistry, University of Paris, INSERM, T3S, 75006 Paris, France
| | - Gabriella Garruti
- Department of Endocrinology, University of Bari "Aldo Moro," Bari, Italy
| | - Michael Gilbertson
- Occupational and Environmental Health Research Group, University of Stirling, Stirling, Scotland
| | - Lori A Hoepner
- Department of Environmental and Occupational Health Sciences, School of Public Health, SUNY Downstate Health Sciences University, Brooklyn, NY 11203, USA
| | - Alison C Holloway
- McMaster University, Department of Obstetrics and Gynecology, Hamilton, Ontario, CA, USA
| | - George Howell
- Center for Environmental Health Sciences, Mississippi State University, Mississippi State, MS 39762, USA
| | - Christopher D Kassotis
- Institute of Environmental Health Sciences and Department of Pharmacology, Wayne State University, Detroit, MI 48202, USA
| | - Mathew K Kay
- College of Pharmacy, Texas A&M University, College Station, TX 77843, USA
| | - Min Ji Kim
- Sorbonne Paris Nord University, Bobigny, INSERM U1124 (T3S), Paris, France
| | | | - Sophie Langouet
- Univ Rennes, INSERM EHESP, IRSET UMR_5S 1085, 35000 Rennes, France
| | - Antoine Legrand
- Sorbonne Paris Nord University, Bobigny, INSERM U1124 (T3S), Paris, France
| | - Zhuorui Li
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA
| | - Helene Le Mentec
- Sorbonne Paris Nord University, Bobigny, INSERM U1124 (T3S), Paris, France
| | - Lars Lind
- Clinical Epidemiology, Department of Medical Sciences, Uppsala University Hospital, Uppsala University, Uppsala, Sweden
| | - P Monica Lind
- Occupational and Environmental Medicine, Department of Medical Sciences, Uppsala University Hospital, Uppsala University, Uppsala, Sweden
| | - Robert H Lustig
- Division of Endocrinology, Department of Pediatrics, University of California San Francisco, CA 94143, USA
| | | | - Vesna Munic Kos
- Department of Physiology and Pharmacology, Karolinska Institute, Solna, Sweden
| | - Normand Podechard
- Sorbonne Paris Nord University, Bobigny, INSERM U1124 (T3S), Paris, France
| | - Troy A Roepke
- Department of Animal Science, School of Environmental and Biological Science, Rutgers University, New Brunswick, NJ 08901, USA
| | - Robert M Sargis
- Division of Endocrinology, Diabetes and Metabolism, The University of Illinois at Chicago, Chicago, Il 60612, USA
| | - Anne Starling
- Department of Epidemiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Craig R Tomlinson
- Norris Cotton Cancer Center, Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA
| | - Charbel Touma
- Sorbonne Paris Nord University, Bobigny, INSERM U1124 (T3S), Paris, France
| | - Jan Vondracek
- Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, Brno, Czech Republic
| | - Frederick Vom Saal
- Division of Biological Sciences, The University of Missouri, Columbia, MO 65211, USA
| | - Bruce Blumberg
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA
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21
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Lagunas‐Rangel FA, Linnea‐Niemi JV, Kudłak B, Williams MJ, Jönsson J, Schiöth HB. Role of the Synergistic Interactions of Environmental Pollutants in the Development of Cancer. GEOHEALTH 2022; 6:e2021GH000552. [PMID: 35493962 PMCID: PMC9036628 DOI: 10.1029/2021gh000552] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 03/01/2022] [Accepted: 04/04/2022] [Indexed: 05/08/2023]
Abstract
There is a growing awareness that the large number of environmental pollutants we are exposed to on a daily basis are causing major health problems. Compared to traditional studies that focus on individual pollutants, there are relatively few studies on how pollutants mixtures interact. Several studies have reported a relationship between environmental pollutants and the development of cancer, even when pollutant levels are below toxicity reference values. The possibility of synergistic interactions between different pollutants could explain how even low concentrations can cause major health problems. These intricate that molecular interactions can occur through a wide variety of mechanisms, and our understanding of the physiological effects of mixtures is still limited. The purpose of this paper is to discuss recent reports that address possible synergistic interactions between different types of environmental pollutants that could promote cancer development. Our literature studies suggest that key biological pathways are frequently implicated in such processes. These include increased production of reactive oxygen species, activation by cytochrome P450, and aryl hydrocarbon receptor signaling, among others. We discuss the need to understand individual pathological vulnerability not only in relation to basic genetics and gene expression, but also in terms of measurable exposure to contaminants. We also mention the need for significant improvements in future studies using a multitude of disciplines, such as the development of high-throughput study models, better tools for quantifying pollutants in cancer patients, innovative pharmacological and toxicological studies, and high-efficiency computer analysis, which allow us to analyze the molecular mechanisms of mixtures.
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Affiliation(s)
| | - Jenni Viivi Linnea‐Niemi
- Department of Surgical Sciences, Functional Pharmacology and NeuroscienceUppsala UniversityUppsalaSweden
| | - Błażej Kudłak
- Faculty of ChemistryDepartment of Analytical ChemistryGdańsk University of TechnologyGdańskPoland
| | - Michael J. Williams
- Department of Surgical Sciences, Functional Pharmacology and NeuroscienceUppsala UniversityUppsalaSweden
| | - Jörgen Jönsson
- Department of Surgical Sciences, Functional Pharmacology and NeuroscienceUppsala UniversityUppsalaSweden
| | - Helgi B. Schiöth
- Department of Surgical Sciences, Functional Pharmacology and NeuroscienceUppsala UniversityUppsalaSweden
- Institute of Translational Medicine and BiotechnologyI. M. Sechenov First Moscow State Medical UniversityMoscowRussia
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22
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Cholico GN, Nault R, Zacharewski TR. Genome-Wide ChIPseq Analysis of AhR, COUP-TF, and HNF4 Enrichment in TCDD-Treated Mouse Liver. Int J Mol Sci 2022; 23:1558. [PMID: 35163483 PMCID: PMC8836158 DOI: 10.3390/ijms23031558] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 01/19/2022] [Accepted: 01/27/2022] [Indexed: 02/01/2023] Open
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor known for mediating the toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds. Although the canonical mechanism of AhR activation involves heterodimerization with the aryl hydrocarbon receptor nuclear translocator, other transcriptional regulators that interact with AhR have been identified. Enrichment analysis of motifs in AhR-bound genomic regions implicated co-operation with COUP transcription factor (COUP-TF) and hepatocyte nuclear factor 4 (HNF4). The present study investigated AhR, HNF4α and COUP-TFII genomic binding and effects on gene expression associated with liver-specific function and cell differentiation in response to TCDD. Hepatic ChIPseq data from male C57BL/6 mice at 2 h after oral gavage with 30 µg/kg TCDD were integrated with bulk RNA-sequencing (RNAseq) time-course (2-72 h) and dose-response (0.01-30 µg/kg) datasets to assess putative AhR, HNF4α and COUP-TFII interactions associated with differential gene expression. Functional enrichment analysis of differentially expressed genes (DEGs) identified differential binding enrichment for AhR, COUP-TFII, and HNF4α to regions within liver-specific genes, suggesting intersections associated with the loss of liver-specific functions and hepatocyte differentiation. Analysis found that the repression of liver-specific, HNF4α target and hepatocyte differentiation genes, involved increased AhR and HNF4α binding with decreased COUP-TFII binding. Collectively, these results suggested TCDD-elicited loss of liver-specific functions and markers of hepatocyte differentiation involved interactions between AhR, COUP-TFII and HNF4α.
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Affiliation(s)
| | | | - Tim R. Zacharewski
- Biochemistry & Molecular Biology, Institute for Integrative Toxicology, Michigan State University, East Lansing, MI 48824, USA; (G.N.C.); (R.N.)
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23
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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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24
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Cholico GN, Fling RR, Zacharewski NA, Fader KA, Nault R, Zacharewski TR. Thioesterase induction by 2,3,7,8-tetrachlorodibenzo-p-dioxin results in a futile cycle that inhibits hepatic β-oxidation. Sci Rep 2021; 11:15689. [PMID: 34344994 PMCID: PMC8333094 DOI: 10.1038/s41598-021-95214-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 07/15/2021] [Indexed: 02/07/2023] Open
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a persistent environmental contaminant, induces steatosis by increasing hepatic uptake of dietary and mobilized peripheral fats, inhibiting lipoprotein export, and repressing β-oxidation. In this study, the mechanism of β-oxidation inhibition was investigated by testing the hypothesis that TCDD dose-dependently repressed straight-chain fatty acid oxidation gene expression in mice following oral gavage every 4 days for 28 days. Untargeted metabolomic analysis revealed a dose-dependent decrease in hepatic acyl-CoA levels, while octenoyl-CoA and dicarboxylic acid levels increased. TCDD also dose-dependently repressed the hepatic gene expression associated with triacylglycerol and cholesterol ester hydrolysis, fatty acid binding proteins, fatty acid activation, and 3-ketoacyl-CoA thiolysis while inducing acyl-CoA hydrolysis. Moreover, octenoyl-CoA blocked the hydration of crotonyl-CoA suggesting short chain enoyl-CoA hydratase (ECHS1) activity was inhibited. Collectively, the integration of metabolomics and RNA-seq data suggested TCDD induced a futile cycle of fatty acid activation and acyl-CoA hydrolysis resulting in incomplete β-oxidation, and the accumulation octenoyl-CoA levels that inhibited the activity of short chain enoyl-CoA hydratase (ECHS1).
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Affiliation(s)
- Giovan N Cholico
- Department of Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Russell R Fling
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
- Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, 48824, USA
| | - Nicholas A Zacharewski
- Department of Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
| | - Kelly A Fader
- Department of Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Rance Nault
- Department of Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Timothy R Zacharewski
- Department of Biochemistry and Molecular Biology, Michigan State University, Biochemistry Building, 603 Wilson Road, East Lansing, MI, 48824, USA.
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA.
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25
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Liu Q, Zhang L, Allman EL, Hubbard TD, Murray IA, Hao F, Tian Y, Gui W, Nichols RG, Smith PB, Anitha M, Perdew GH, Patterson AD. The aryl hydrocarbon receptor activates ceramide biosynthesis in mice contributing to hepatic lipogenesis. Toxicology 2021; 458:152831. [PMID: 34097992 DOI: 10.1016/j.tox.2021.152831] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 05/10/2021] [Accepted: 06/02/2021] [Indexed: 12/18/2022]
Abstract
Aryl hydrocarbon receptor (AHR) activation via 2,3,7,8-tetrachlorodibenzofuran (TCDF) induces the accumulation of hepatic lipids. Here we report that AHR activation by TCDF (24 μg/kg body weight given orally for five days) induced significant elevation of hepatic lipids including ceramides in mice, was associated with increased expression of key ceramide biosynthetic genes, and increased activity of their respective enzymes. Results from chromatin immunoprecipitation (ChIP), electrophoretic mobility shift assay (EMSA) and cell-based reporter luciferase assays indicated that AHR directly activated the serine palmitoyltransferase long chain base subunit 2 (Sptlc2, encodes serine palmitoyltransferase 2 (SPT2)) gene whose product catalyzes the initial rate-limiting step in de novo sphingolipid biosynthesis. Hepatic ceramide accumulation was further confirmed by mass spectrometry-based lipidomics. Taken together, our results revealed that AHR activation results in the up-regulation of Sptlc2, leading to ceramide accumulation, thus promoting lipogenesis, which can induce hepatic lipid accumulation.
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Affiliation(s)
- Qing Liu
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Limin Zhang
- CAS Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Centre for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences (CAS), Wuhan, 430071, China
| | - Erik L Allman
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Troy D Hubbard
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Iain A Murray
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Fuhua Hao
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Yuan Tian
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Wei Gui
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Robert G Nichols
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Philip B Smith
- Huck Institutes of the Life Sciences, University Park, PA, 16802, USA
| | - Mallappa Anitha
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Gary H Perdew
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Andrew D Patterson
- Center for Molecular Toxicology and Carcinogenesis, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, 16802, USA.
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26
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Le Magueresse-Battistoni B. Endocrine disrupting chemicals and metabolic disorders in the liver: What if we also looked at the female side? CHEMOSPHERE 2021; 268:129212. [PMID: 33359838 DOI: 10.1016/j.chemosphere.2020.129212] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 12/01/2020] [Accepted: 12/02/2020] [Indexed: 05/07/2023]
Abstract
Endocrine disrupting chemicals (EDCs) are linked to the worldwide epidemic incidence of metabolic disorders and fatty liver diseases, which affects quality of life and represents a high economic cost to society. Energy homeostasis exhibits strong sexual dimorphic traits, and metabolic organs respond to EDCs depending on sex, such as the liver, which orchestrates both drug elimination and glucose and lipid metabolism. In addition, fatty liver diseases show a strong sexual bias, which in part could also originate from sex differences observed in gut microbiota. The aim of this review is to highlight significant differences in endocrine and metabolic aspects of the liver, between males and females throughout development and into adulthood. It is also to illustrate how the male and female liver differently cope with exposure to various EDCs such as bisphenols, phthalates and persistent organic chemicals in order to draw attention to the need to include both sexes in experimental studies. Interesting data come from analyses of the composition and diversity of the gut microbiota in males exposed to the mentioned EDCs showing significant correlations with hepatic lipid accumulation and metabolic disorders but information on females is lacking or incomplete. As industrialization increases, the list of anthropogenic chemicals to which humans will be exposed will also likely increase. In addition to strengthening existing regulations, encouraging populations to protect themselves and promoting the substitution of harmful chemicals with safe products, innovative strategies based on sex differences in the gut microbiota and in the gut-liver axis could be optimistic outlook.
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27
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Bottalico LN, Weljie AM. Cross-species physiological interactions of endocrine disrupting chemicals with the circadian clock. Gen Comp Endocrinol 2021; 301:113650. [PMID: 33166531 PMCID: PMC7993548 DOI: 10.1016/j.ygcen.2020.113650] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 10/09/2020] [Accepted: 10/17/2020] [Indexed: 02/06/2023]
Abstract
Endocrine disrupting chemicals (EDCs) are endocrine-active chemical pollutants that disrupt reproductive, neuroendocrine, cardiovascular and metabolic health across species. The circadian clock is a transcriptional oscillator responsible for entraining 24-hour rhythms of physiology, behavior and metabolism. Extensive bidirectional cross talk exists between circadian and endocrine systems and circadian rhythmicity is present at all levels of endocrine control, from synthesis and release of hormones, to sensitivity of target tissues to hormone action. In mammals, a range of hormones directly alter clock gene expression and circadian physiology via nuclear receptor (NR) binding and subsequent genomic action, modulating physiological processes such as nutrient and energy metabolism, stress response, reproductive physiology and circadian behavioral rhythms. The potential for EDCs to perturb circadian clocks or circadian-driven physiology is not well characterized. For this reason, we explore evidence for parallel endocrine and circadian disruption following EDC exposure across species. In the reviewed studies, EDCs dysregulated core clock and circadian rhythm network gene expression in brain and peripheral organs, and altered circadian reproductive, behavioral and metabolic rhythms. Circadian impacts occurred in parallel to endocrine and metabolic alterations such as impaired fertility and dysregulated metabolic and energetic homeostasis. Further research is warranted to understand the nature of interaction between circadian and endocrine systems in mediating physiological effects of EDC exposure at environmental levels.
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Affiliation(s)
- Lisa N Bottalico
- Department of Systems Pharmacology and Translational Therapeutics, Institute for Translational Medicine and Therapeutics, Center of Excellence in Environmental Toxicology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Aalim M Weljie
- Department of Systems Pharmacology and Translational Therapeutics, Institute for Translational Medicine and Therapeutics, Center of Excellence in Environmental Toxicology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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28
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Küblbeck J, Niskanen J, Honkakoski P. Metabolism-Disrupting Chemicals and the Constitutive Androstane Receptor CAR. Cells 2020; 9:E2306. [PMID: 33076503 PMCID: PMC7602645 DOI: 10.3390/cells9102306] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/13/2020] [Accepted: 10/13/2020] [Indexed: 02/07/2023] Open
Abstract
During the last two decades, the constitutive androstane receptor (CAR; NR1I3) has emerged as a master activator of drug- and xenobiotic-metabolizing enzymes and transporters that govern the clearance of both exogenous and endogenous small molecules. Recent studies indicate that CAR participates, together with other nuclear receptors (NRs) and transcription factors, in regulation of hepatic glucose and lipid metabolism, hepatocyte communication, proliferation and toxicity, and liver tumor development in rodents. Endocrine-disrupting chemicals (EDCs) constitute a wide range of persistent organic compounds that have been associated with aberrations of hormone-dependent physiological processes. Their adverse health effects include metabolic alterations such as diabetes, obesity, and fatty liver disease in animal models and humans exposed to EDCs. As numerous xenobiotics can activate CAR, its role in EDC-elicited adverse metabolic effects has gained much interest. Here, we review the key features and mechanisms of CAR as a xenobiotic-sensing receptor, species differences and selectivity of CAR ligands, contribution of CAR to regulation hepatic metabolism, and evidence for CAR-dependent EDC action therein.
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Affiliation(s)
- Jenni Küblbeck
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, FI-70210 Kuopio, Finland;
- School of Pharmacy, University of Eastern Finland, P.O. Box 1627, FI-70210 Kuopio, Finland;
| | - Jonna Niskanen
- School of Pharmacy, University of Eastern Finland, P.O. Box 1627, FI-70210 Kuopio, Finland;
| | - Paavo Honkakoski
- School of Pharmacy, University of Eastern Finland, P.O. Box 1627, FI-70210 Kuopio, Finland;
- Division of Pharmacotherapy and Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Campus Box 7569, Chapel Hill, NC 27599-7569, USA
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29
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Fling RR, Doskey CM, Fader KA, Nault R, Zacharewski TR. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) dysregulates hepatic one carbon metabolism during the progression of steatosis to steatohepatitis with fibrosis in mice. Sci Rep 2020; 10:14831. [PMID: 32908189 PMCID: PMC7481292 DOI: 10.1038/s41598-020-71795-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 07/29/2020] [Indexed: 12/13/2022] Open
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a persistent environmental contaminant, induces steatosis that can progress to steatohepatitis with fibrosis, pathologies that parallel stages in the development of non-alcoholic fatty liver disease (NAFLD). Coincidently, one carbon metabolism (OCM) gene expression and metabolites are often altered during NAFLD progression. In this study, the time- and dose-dependent effects of TCDD were examined on hepatic OCM in mice. Despite AhR ChIP-seq enrichment at 2 h, OCM gene expression was not changed within 72 h following a bolus dose of TCDD. Dose-dependent repression of methionine adenosyltransferase 1A (Mat1a), adenosylhomocysteinase (Achy) and betaine-homocysteine S-methyltransferase (Bhmt) mRNA and protein levels following repeated treatments were greater at 28 days compared to 8 days. Accordingly, levels of methionine, betaine, and homocysteic acid were dose-dependently increased, while S-adenosylmethionine, S-adenosylhomocysteine, and cystathionine exhibited non-monotonic dose-dependent responses consistent with regulation by OCM intermediates and repression of glycine N-methyltransferase (Gnmt). However, the dose-dependent effects on SAM-dependent metabolism of polyamines and creatine could not be directly attributed to alterations in SAM levels. Collectively, these results demonstrate persistent AhR activation disrupts hepatic OCM metabolism at the transcript, protein and metabolite levels within context of TCDD-elicited progression of steatosis to steatohepatitis with fibrosis.
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Affiliation(s)
- Russell R Fling
- Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Claire M Doskey
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Kelly A Fader
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Rance Nault
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA
| | - Tim R Zacharewski
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, 48824, USA.
- Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, 48824, USA.
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30
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Nault R, Fader KA, Bhattacharya S, Zacharewski TR. Single-Nuclei RNA Sequencing Assessment of the Hepatic Effects of 2,3,7,8-Tetrachlorodibenzo-p-dioxin. Cell Mol Gastroenterol Hepatol 2020; 11:147-159. [PMID: 32791302 PMCID: PMC7674514 DOI: 10.1016/j.jcmgh.2020.07.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 07/31/2020] [Accepted: 07/31/2020] [Indexed: 12/21/2022]
Abstract
BACKGROUND AND AIMS Characterization of cell specific transcriptional responses to hepatotoxicants is lost in the averages of bulk RNA-sequencing (RNA-seq). Single-cell/nuclei RNA-seq technologies enable the transcriptomes of individual cell (sub)types to be assessed within the context of in vivo models. METHODS Single-nuclei RNA-sequencing (snSeq) of frozen liver samples from male C57BL/6 mice gavaged with sesame oil vehicle or 30 μg/kg 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) every 4 days for 28 days was used to demonstrate the application of snSeq for the evaluation of xenobiotics. RESULTS A total of 19,907 genes were detected across 16,015 nuclei from control and TCDD-treated livers. Eleven cell (sub)types reflected the expected cell diversity of the liver including distinct pericentral, midzonal, and periportal hepatocyte subpopulations. TCDD altered relative proportions of cell types and elicited cell-specific gene expression profiles. For example, macrophages increased from 0.5% to 24.7%, while neutrophils were only present in treated samples, consistent with histological evaluation. The number of differentially expressed genes (DEGs) in each cell type ranged from 122 (cholangiocytes) to 7625 (midcentral hepatocytes), and loosely correlated with the basal expression level of Ahr, the canonical mediator of TCDD and related compounds. In addition to the expected functions within each cell (sub)types, RAS signaling and related pathways were specifically enriched in nonparenchymal cells while metabolic process enrichment occurred primarily in hepatocytes. snSeq also identified the expansion of a Kupffer cell subtype highly expressing Gpnmb, as reported in a dietary NASH model. CONCLUSIONS We show that snSeq of frozen liver samples can be used to assess cell-specific transcriptional changes and population shifts in models of hepatotoxicity when examining freshly isolated cells is not feasible.
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Affiliation(s)
- Rance Nault
- Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan
| | - Kelly A Fader
- Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan
| | - Sudin Bhattacharya
- Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan; Department of Biomedical Engineering, Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, Michigan; Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - Tim R Zacharewski
- Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan.
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Ndikung J, Storm D, Violet N, Kramer A, Schönfelder G, Ertych N, Oelgeschläger M. Restoring circadian synchrony in vitro facilitates physiological responses to environmental chemicals. ENVIRONMENT INTERNATIONAL 2020; 134:105265. [PMID: 31734582 DOI: 10.1016/j.envint.2019.105265] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 09/26/2019] [Accepted: 10/13/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND The growing requirement of hazard and risk assessment of environmental chemicals and the efforts to minimize animal testing, increases the demand for innovative and predictive in vitro test systems in toxicology, reflecting the physiological conditions of human nature. Here, an elemental factor regulating a variety of physiological processes is the day-night rhythm. This circadian rhythm, describing a biological oscillation with a 24-h period is hardly acknowledged in toxicology and test method development. Whilst, in animals or humans the entire organism exhibits a rigorous cellular circadian synchrony, in conventional in vitro systems each cell follows its own rhythm, due to the absence of appropriate synchronizing signals. OBJECTIVE Here we investigated whether circadian synchronization of human cells in an in vitro system improves the cellular response and, thus, increases the sensitivity of the test system. Since the circadian regulation of metabolism is particularly well understood, and dioxin and dioxin-like compounds are of major concern for environmental health we focused on the ubiquitous drug metabolizing detoxification system mediated by the aryl hydrocarbon receptor (AHR). METHODS To this end, we applied various prototypical AHR activators onto different human cell lines under non-synchronized or circadian synchronized conditions and determined the dose response on representative endogenous target genes. RESULTS Remarkably, the cellular response dynamic upon chemical treatment was substantially enhanced in circadian synchronized cells and followed a rhythmic expression pattern. This broader dynamic range was associated with a strikingly higher induction of AHR target genes and the corresponding enzymatic activity, thereby rather mimicking the in vivo situation. CONCLUSION Our findings indicate that a synchronized circadian rhythm in a cell culture based test system can improve the physiological relevance of an appropriate in vitro method by reflecting the biological in vivo situation more closely. Accordingly, it is a promising tool to facilitate the wide acceptance of in vitro methods in the field of regulatory toxicology and to further optimize the toxicological assessment of environmental chemicals.
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Affiliation(s)
- Johanna Ndikung
- German Federal Institute for Risk Assessment, German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277 Berlin, Germany
| | - Dorothe Storm
- German Federal Institute for Risk Assessment, German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277 Berlin, Germany
| | - Norman Violet
- German Federal Institute for Risk Assessment, German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277 Berlin, Germany
| | - Achim Kramer
- Laboratory of Chronobiology, Charité - Universitätsmedizin Berlin, Germany
| | - Gilbert Schönfelder
- German Federal Institute for Risk Assessment, German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277 Berlin, Germany; Department of Clinical Pharmacology and Toxicology, Charité - Universitätsmedizin Berlin, Germany
| | - Norman Ertych
- German Federal Institute for Risk Assessment, German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277 Berlin, Germany.
| | - Michael Oelgeschläger
- German Federal Institute for Risk Assessment, German Centre for the Protection of Laboratory Animals (Bf3R), Diedersdorfer Weg 1, 12277 Berlin, Germany
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32
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Butler TD, Gibbs JE. Circadian Host-Microbiome Interactions in Immunity. Front Immunol 2020; 11:1783. [PMID: 32922391 PMCID: PMC7456996 DOI: 10.3389/fimmu.2020.01783] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 07/03/2020] [Indexed: 12/12/2022] Open
Abstract
The gut microbiome plays a critical role in regulating host immunity and can no longer be regarded as a bystander in human health and disease. In recent years, circadian (24 h) oscillations have been identified in the composition of the microbiota, its biophysical localization within the intestinal tract and its metabolic outputs. The gut microbiome and its key metabolic outputs, such as short chain fatty acids and tryptophan metabolites contribute to maintenance of intestinal immunity by promoting barrier function, regulating the host mucosal immune system and maintaining the function of gut-associated immune cell populations. Loss of rhythmic host-microbiome interactions disrupts host immunity and increases risk of inflammation and metabolic complications. Here we review factors that drive circadian variation in the microbiome, including meal timing, dietary composition and host circadian clocks. We also consider how host-microbiome interactions impact the core molecular clock and its rhythmic outputs in addition to the potential impact of this relationship on circadian control of immunity.
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