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Zhang M, Shi J, Li B, Ge H, Tao H, Zhang J, Li X, Cai Z. Thyroid Hormone Receptor Agonistic and Antagonistic Activity of Newly Synthesized Dihydroxylated Polybrominated Diphenyl Ethers: An In Vitro and In Silico Coactivator Recruitment Study. TOXICS 2024; 12:281. [PMID: 38668504 PMCID: PMC11053510 DOI: 10.3390/toxics12040281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 03/20/2024] [Accepted: 03/28/2024] [Indexed: 04/29/2024]
Abstract
Dihydroxylated polybrominated diphenyl ethers (DiOH-PBDEs) could be the metabolites of PBDEs of some organisms or the natural products of certain marine bacteria and algae. OH-PBDEs may demonstrate binding affinity to thyroid hormone receptors (TRs) and can disrupt the functioning of the systems modulated by TRs. However, the thyroid hormone disruption mechanism of diOH-PBDEs remains elusive due to the absence of diOH-PBDEs standards. This investigation explores the potential disruptive effects of OH/diOH-PBDEs on thyroid hormones via competitive binding and coactivator recruitment with TRα and TRβ. At levels of 5000 nM and 25,000 nM, 6-OH-BDE-47 demonstrated significant recruitment of steroid receptor coactivator (SRC), whereas none of the diOH-PBDEs exhibited SRC recruitment within the range of 0.32-25,000 nM. AutoDock CrankPep (ADCP) simulations suggest that the conformation of SRC and TR-ligand complexes, particularly their interaction with Helix 12, rather than binding affinity, plays a pivotal role in ligand agonistic activity. 6,6'-diOH-BDE-47 displayed antagonistic activity towards both TRα and TRβ, while the antagonism of 3,5-diOH-BDE-100 for TRα and TRβ was concentration-dependent. 3,5-diOH-BDE-17 and 3,5-diOH-BDE-51 exhibited no discernible agonistic or antagonistic activities. Molecular docking analysis revealed that the binding energy of 3,3',5-triiodo-L-thyronine (T3) surpassed that of OH/diOH-PBDEs. 3,5-diOH-BDE-100 exhibited the highest binding energy, whereas 6,6'-diOH-BDE-47 displayed the lowest. These findings suggest that the structural determinants influencing the agonistic and antagonistic activities of halogen phenols may be more intricate than previously proposed, involving factors beyond high-brominated PBDEs or hydroxyl group and bromine substitutions. It is likely that the agonistic or antagonistic propensities of OH/diOH-PBDEs are instigated by protein conformational changes rather than considerations of binding energy.
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Affiliation(s)
- Mengtao Zhang
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; (M.Z.); (H.G.); (H.T.); (J.Z.)
- China State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China;
- Institute of Environment and Ecology, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China; (B.L.); (X.L.)
| | - Jianghong Shi
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; (M.Z.); (H.G.); (H.T.); (J.Z.)
| | - Bing Li
- Institute of Environment and Ecology, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China; (B.L.); (X.L.)
| | - Hui Ge
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; (M.Z.); (H.G.); (H.T.); (J.Z.)
| | - Huanyu Tao
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; (M.Z.); (H.G.); (H.T.); (J.Z.)
| | - Jiawei Zhang
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; (M.Z.); (H.G.); (H.T.); (J.Z.)
| | - Xiaoyan Li
- Institute of Environment and Ecology, Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China; (B.L.); (X.L.)
| | - Zongwei Cai
- China State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China;
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De Oro-Carretero P, Sanz-Landaluze J. Bioaccumulation and Biotransformation of BDE-47 Using Zebrafish Eleutheroembryos (Danio rerio). ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2023; 42:835-845. [PMID: 36705440 DOI: 10.1002/etc.5569] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 11/02/2022] [Accepted: 01/15/2023] [Indexed: 06/18/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are well-known endocrine disrupting chemicals identified as organic persistent pollutants. Their metabolites OH-BDE and MeO-BDE have been reported to be potentially more toxic than the postulated precursor PBDEs. One of the most predominant congeners of PBDEs in the environment is BDE-47, due to its high presence in industrially used mixtures. In the present study, the bioaccumulation and biotransformation of BDE-47 into its major metabolites is evaluated using zebrafish (Danio rerio) eleutheroembryos adapting a previously developed alternative method to bioconcentration official guideline Organisation for Economic Co-ordination and Development 305, which reduces the animal suffering, time, and cost. For the simultaneous determination of BDE-47 and its metabolites in larvae and exposure medium, and considering the polarity difference of the analytes and the small sample size, the development of a validated analytical method is a step to ensure quality results. In the present study, an ultrasound-assisted extraction followed by a solid phase extraction dispersive clean-up step and gas chromatography-mass spectrometry-microelectron capture detector (GC-MS-μECD) with a previous derivatization process was optimized and validated. Bioconcentration factors (BCFs) were calculated using a first-order one-compartment toxicokinetic model. The profiles found show rapid absorption in the first hours of larval development and great bioaccumulative capacity, finding BCFs of 7294 ± 899 and 36 363 ± 5702 at nominal concentrations of 10 and 1 μg L-1 , respectively. Metabolization studies show increasing concentrations of the metabolites BDE-28, 2'-OH-BDE-28, and 5-MeO-BDE-47 throughout the exposure time. The results obtained show the feasibility of the method for bioaccumulation and open up the possibility of metabolic studies with zebrafish eleutheroembryos, which is a very underdeveloped field without official testing or regulation. Environ Toxicol Chem 2023;42:835-845. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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Affiliation(s)
- Paloma De Oro-Carretero
- Department of Analytical Chemistry, Faculty of Chemical Science, Complutense University of Madrid, Madrid, Spain
| | - Jon Sanz-Landaluze
- Department of Analytical Chemistry, Faculty of Chemical Science, Complutense University of Madrid, Madrid, Spain
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Gustafsson J, Legradi J, Lamoree MH, Asplund L, Leonards PEG. Metabolite alterations in zebrafish embryos exposed to hydroxylated polybrominated diphenyl ethers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159269. [PMID: 36208744 DOI: 10.1016/j.scitotenv.2022.159269] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 09/24/2022] [Accepted: 10/02/2022] [Indexed: 06/16/2023]
Abstract
Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) are formed by metabolism from the flame retardants polybrominated diphenyl ethers (PBDEs). In the aquatic environment, they are also produced naturally. OH-PBDEs are known for their potential to disrupt energy metabolism, the endocrine system, and the nervous system. This is the first study focusing on the effects of OH-PBDEs at the metabolite level in vivo. The aim of the current study was to investigate the metabolic effects of exposure to OH-PBDEs using metabolomics, and to identify potential biomarker(s) for energy disruption of OH-PBDEs. Zebrafish (Danio rerio) embryos were exposed to two different concentrations of 6-OH-BDE47 and 6-OH-BDE85 and a mixture of these two compounds. In total, 342 metabolites were annotated and 79 metabolites were affected in at least one exposure. Several affected metabolites, e.g. succinic acid, glutamic acid, glutamine, tyrosine, tryptophan, adenine, and several fatty acids, could be connected to known toxic mechanisms of OH-PBDEs. Several phospholipids were strongly up-regulated with up to a six-fold increase after exposure to 6-OH-BDE47, a scarcely described effect of OH-PBDEs. Based on the observed metabolic effects, a possible connection between disruption of the energy metabolism, neurotoxicity and potential immunotoxicity of OH-PBDEs was suggested. Single compound exposures to 6-OH-BDE47 and 6-OH-BDE85 showed little overlap in the affected metabolites. This shows that compounds of similar chemical structure can induce different metabolic effects, possibly relating to their different toxic mechanisms. There were inter-concentration differences in the metabolic profiles, indicating that the metabolic effects were concentration dependent. After exposure to the mixture of 6-OH-BDE47 and 6-OH-BDE85, a new metabolic profile distinct from the profiles obtained from the single compounds was observed. Succinic acid was up-regulated at the highest, but still environmentally relevant, concentration of 6-OH-BDE47, 6-OH-BDE85, and the mixture. Therefore, succinic acid is suggested as a potential biomarker for energy disruption of OH-PBDEs.
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Affiliation(s)
- Johan Gustafsson
- Department of Environmental Science, Stockholm University, Stockholm, Sweden; Amsterdam Institute for Life and Environment, Vrije Universiteit, Amsterdam, the Netherlands.
| | - Jessica Legradi
- Amsterdam Institute for Life and Environment, Vrije Universiteit, Amsterdam, the Netherlands
| | - Marja H Lamoree
- Amsterdam Institute for Life and Environment, Vrije Universiteit, Amsterdam, the Netherlands
| | - Lillemor Asplund
- Department of Environmental Science, Stockholm University, Stockholm, Sweden
| | - Pim E G Leonards
- Amsterdam Institute for Life and Environment, Vrije Universiteit, Amsterdam, the Netherlands
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Li T, Sun Y, Zeng Y, Sanganyado E, Liang B, Liu W. 6-OH-BDE-47 inhibited proliferation of skin fibroblasts from pygmy killer whale by inducing cell cycle arrest. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 807:150561. [PMID: 34624692 DOI: 10.1016/j.scitotenv.2021.150561] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 08/16/2021] [Accepted: 09/20/2021] [Indexed: 06/13/2023]
Abstract
Hydroxylated polybrominated diphenyl ethers (OH-BDEs) are major transformation products of PBDEs that readily bioaccumulate in the marine food web. Although 6-OH-BDE-47 is frequently and abundantly detected in cetaceans, its potential toxic effects are largely unknown. We explored the toxicological pathways and mechanisms of OH-BDEs by exposing pygmy killer whale skin fibroblast cell lines (PKW-LWHT) to 6-OH-BDE-47 at concentrations ranging from 0.02, 0.2, 2 to 4 μM. The result showed that 6-OH-BDE-47 inhibited cell proliferation in a concentration- and time-dependent manner. The cell cycle data revealed that the cell cycle was arrest at the G0/G1 phase by 6-OH-BDE-47. Using qPCR and Western blot assay, we found that 6-OH-BDE-47 up-regulated the transcription and expression level of p21 and RB1 and down-regulated the expression level of Proliferating Cell Nuclear Antigen (PCNA), CDK2, CDK4, cyclin D1, cyclin E2, E2F1, and E2F3 and the cellular phosphorylated RB1. The results showed that 6-OH-BDE-47 was able to arrest the cell cycle of PKW-LWHT cells at G1 phase by changing the expression level of related regulatory genes in G1 stage, and finally inhibit cell proliferation.
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Affiliation(s)
- Tong Li
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Science, Shantou University, Shantou, Guangdong 515063, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
| | - Yajing Sun
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Science, Shantou University, Shantou, Guangdong 515063, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
| | - Ying Zeng
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Science, Shantou University, Shantou, Guangdong 515063, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
| | - Edmond Sanganyado
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Science, Shantou University, Shantou, Guangdong 515063, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China
| | - Bo Liang
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Science, Shantou University, Shantou, Guangdong 515063, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China.
| | - Wenhua Liu
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Science, Shantou University, Shantou, Guangdong 515063, China; Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou 511458, China.
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Wei J, Xiang L, Cai Z. Emerging environmental pollutants hydroxylated polybrominated diphenyl ethers: From analytical methods to toxicology research. MASS SPECTROMETRY REVIEWS 2021; 40:255-279. [PMID: 32608069 DOI: 10.1002/mas.21640] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/13/2020] [Accepted: 05/23/2020] [Indexed: 06/11/2023]
Abstract
Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) are of particular concern due to their ubiquitous distribution and adverse health effects. Significant progress has been made in the characterization of OH-PBDEs by using mass spectrometry (MS). In this review, we summarize applications of MS-based techniques in detection, environmental and biota distribution, and potential health risk effects, hoping to unfold an overall picture on account of current knowledge of OH-PBDEs. The analytical methodologies are discussed from sample pretreatment to MS analysis. The methods including gas chromatography-MS (GC-MS), liquid chromatography-MS (LC-MS), and ion mobility spectrometry-MS (IMS-MS) are discussed. GC-MS is the most frequently adopted method in the analysis of OH-PBDEs due to its excellent chromatographic resolution, high sensitivity, and strong ability for unknown identification. LC-MS has been widely used for its high sensitivity and capability of direct analysis. As a newly developed technique, IMS-MS provides high specificity, which greatly facilitates the identification of isomers. OH-PBDEs pervasively existed in both abiotic and biotic samples, including humans, animals, and environmental matrices. Multiple adverse health effects have been reported, such as thyroid hormone disruption, estrogen effects, and neurotoxicity. The reported potential pathological mechanisms are also reviewed. Additionally, MS-based metabolomics, lipidomics, and proteomics have been shown as promising tools to unveil the molecular mechanisms of the toxicity of OH-PBDEs. © 2020 John Wiley & Sons Ltd. Mass Spec Rev.
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Affiliation(s)
- Juntong Wei
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong SAR, China
| | - Li Xiang
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong SAR, China
| | - Zongwei Cai
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong SAR, China
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6
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Zhang M, Zhao F, Zhang J, Shi J, Tao H, Ge H, Guo W, Liu D, Cai Z. Toxicity and accumulation of 6-OH-BDE-47 and newly synthesized 6,6'-diOH-BDE-47 in early life-stages of Zebrafish (Danio rerio). THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 763:143036. [PMID: 33131876 DOI: 10.1016/j.scitotenv.2020.143036] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 10/07/2020] [Accepted: 10/10/2020] [Indexed: 06/11/2023]
Abstract
Dihydroxylated polybrominated diphenyl ethers (diOH-PBDEs) appear to be natural products or metabolites of PBDEs in some marine organisms, yet its toxicity is still largely unknown. With a newly lab-synthesized diOH-PBDE, 6,6'-dihydroxy-2,2',4'4'-tetrabromodiphenyl ether (6,6'-diOH-BDE-47) in hand, the present study has provided the first data set to compare 6-hydroxy-2,2',4'4'- tetrabromodiphenyl ether (6-OH-BDE-47) and 6,6'-diOH-BDE-47 for their acute toxicity and accumulation, and thyroid hormone levels in treated zebrafish larvae. By real time-PCR technique, transcripts of hypothalamic-pituitary-thyroid axis associated genes were also investigated in developing larvae at 96 h post fertilization (96 hpf). Apparently, 6,6'-diOH-BDE-47 was less toxic than that of 6-OH-BDE-47: 1) the 96-h LC50 (96-h median lethal concentration) of 6-OH-BDE-47 and 6,6'-diOH-BDE-47 were 235 nM and 516 nM, respectively; 2) although severe developmental delays and morphological deformities were observed in zebrafish larvae in high exposure doses, at the exposure concentration of 1-50 nM, the accumulated 6-OH-BDE-47 and 6,6'-diOH-BDE-47 is ranged between 226-2279 nmol/g and 123-539 nmol/g in treated larvae; and 3) for 6-OH-BDE-47, its bioconcentration factor (BCF) were 1.83- to 4.30-fold more than that of 6,6'-diOH-BDE-47, suggesting that the lower internal exposure concentration of 6,6'-diOH-BDE-47 may lead to lower toxicity. The increased thyroid hormone levels were recorded for 1 nM of 6-OH-BDE-47 and 20 nM of 6,6'-diOH-BDE-47, and the exposures both significantly increased thyroid gland-specific transcription of thyroglobulin gene, indicating an adverse effect associated with the HPT axis. Therefore, 6,6'-diOH-BDE-47, with lower toxicity compared to that of 6-OH-BDE-47, still possesses hazards and environmental risk.
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Affiliation(s)
- Mengtao Zhang
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; China State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China
| | - Feng Zhao
- Department of Biology, Southern University of Science and Technology, Shenzhen, China
| | - Jiawei Zhang
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Jianghong Shi
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Huanyu Tao
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Hui Ge
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Wei Guo
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Dong Liu
- Department of Biology, Southern University of Science and Technology, Shenzhen, China
| | - Zongwei Cai
- China State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China.
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Félix LM, Luzio A, Santos A, Antunes LM, Coimbra AM, Valentim AM. MS-222 induces biochemical and transcriptional changes related to oxidative stress, cell proliferation and apoptosis in zebrafish embryos. Comp Biochem Physiol C Toxicol Pharmacol 2020; 237:108834. [PMID: 32585370 DOI: 10.1016/j.cbpc.2020.108834] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/23/2020] [Accepted: 06/19/2020] [Indexed: 12/19/2022]
Abstract
MS-222, the most widely used anaesthetic in fish, has been shown to induce embryotoxic effects in zebrafish. However, the underlying molecular effects are still elusive. This study aimed to investigate the effects of MS-222 exposure during early developmental stages by evaluating biochemical and molecular changes. Embryos were exposed to 50, 100 or 150 mg L-1 MS-222 for 20 min at one of three developmental stages (256-cell, 50% epiboly, or 1-4 somite stage) and oxidative-stress, cell proliferation and apoptosis-related parameters were determined at two time-points (8 and 26 hpf). Following exposure during the 256-cell stage, the biochemical redox balance was not affected. The genes associated with glutathione homeostasis (gstpi and gclc) were affected at 8 hpf, while genes associated with apoptosis (casp3a and casp6) and cellular proliferation (pcna) were found affected at 26 hpf. An inverted U-shaped response was observed at 8 hpf for catalase activity. After exposure at the 50% epiboly stage, the gclc gene associated with oxidative stress was found upregulated at 8 hpf, while gstpi was downregulated and casp6 was upregulated later on, coinciding with a decrease in glutathione peroxidase (GPx) activity and a non-monotonic elevation of protein carbonyls and casp3a. Additionally, MS-222 treated embryos showed a decrease in DCF-staining at 26 hpf. When exposure was performed at the 1-4 somite stage, a similar DCF-staining pattern was observed. The activity of GPx was also affected whereas RT-qPCR showed that caspase transcripts were dose-dependently increased (casp3a, casp6 and casp9). The pcna mRNA levels were also found to be upregulated while gclc was changed by MS-222. These results highlight the impact of MS-222 on zebrafish embryo development and its interference with the antioxidant, cell proliferation and cellular death systems by mechanisms still to be explained; however, the outcomes point to the Erk/Nrf2 signalling pathway as a target candidate.
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Affiliation(s)
- Luís M Félix
- Instituto de Investigação e Inovação em Saúde (i3S), Laboratory Animal Science (LAS), Instituto de Biologia Molecular Celular (IBMC), Universidade of Porto (UP), Porto, Portugal; Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal.
| | - Ana Luzio
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
| | - Ana Santos
- School of Life and Environmental Sciences (ECVA), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
| | - Luís M Antunes
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal; School of Agrarian and Veterinary Sciences (ECAV), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
| | - Ana M Coimbra
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal; School of Life and Environmental Sciences (ECVA), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
| | - Ana M Valentim
- Instituto de Investigação e Inovação em Saúde (i3S), Laboratory Animal Science (LAS), Instituto de Biologia Molecular Celular (IBMC), Universidade of Porto (UP), Porto, Portugal
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González-Doncel M, Fernández Torija C, Pablos MV, García Hortigüela P, López Arévalo M, Beltrán EM. The role of PFOS on triclosan toxicity to two model freshwater organisms. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 263:114604. [PMID: 33618454 DOI: 10.1016/j.envpol.2020.114604] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 04/02/2020] [Accepted: 04/14/2020] [Indexed: 06/12/2023]
Abstract
Surface-active substances may enhance the bioavailability of certain pollutants by modifying the permeability of cell membranes. However, they could also interact in a positive manner by increasing toxicity to aquatic organisms. A comparative effects assessment of waterborne exposure to triclosan (TCS) alone vs. combined with perfluorooctanesulfonic acid (PFOS) was herein investigated in daphnids (Daphnia magna) and medaka (Oryzias latipes) early life stages (ELS) using a battery of non-invasive behavioral, physiological and anatomical endpoints. Additionally, TCS bioaccumulation was evaluated in medaka embryos to help discern differences in effects caused by either, changes in TCS permeability or by a positive interaction with PFOS. The TCS analytical measurements in the medaka ELS exposure media revealed fast dissipation with half-lives < 12 h. The D. magna immobilization and feeding inhibition assays suggested an increased response when TCS (≥200 and 37.50 μg/L, respectively) was co-exposed with PFOS. Concentrations <800 μg TCS/L did not affect medaka ELS. However, exposures to ≥400 μg TCS/L + PFOS had effects on the embryo and eleutheroembryo viability. The morphometric analysis of the embryonic gallbladder area and the oxidative stress, determined in vivo by the manifestation of reactive oxygen species (ROS), revealed a hormetic response in both experimental sets. The TCS + PFOS experimental set generally resulted in increased gallbladder areas and ROS activity levels compared to those quantified in the corresponding TCS set. The bioaccumulation studies in the medaka embryos revealed comparable TCS levels regardless of PFOS presence. Without disregarding any TCS's enhanced bioavailability caused by the surface-active substance, overall results primarily indicate increased biological effects of TCS due to a potentiation action of PFOS as a binary mixture with TCS.
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Affiliation(s)
- Miguel González-Doncel
- Laboratory for Ecotoxicology, Department of the Environment, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040, Madrid, Spain.
| | - Carlos Fernández Torija
- Laboratory for Ecotoxicology, Department of the Environment, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040, Madrid, Spain
| | - María Victoria Pablos
- Laboratory for Ecotoxicology, Department of the Environment, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040, Madrid, Spain
| | - Pilar García Hortigüela
- Laboratory for Ecotoxicology, Department of the Environment, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040, Madrid, Spain
| | - Manuel López Arévalo
- Laboratory for Ecotoxicology, Department of the Environment, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040, Madrid, Spain
| | - Eulalia María Beltrán
- Laboratory for Ecotoxicology, Department of the Environment, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040, Madrid, Spain
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Liu QS, Sun Z, Ren X, Ren Z, Liu A, Zhang J, Zhou Q, Jiang G. Chemical Structure-Related Adipogenic Effects of Tetrabromobisphenol A and Its Analogues on 3T3-L1 Preadipocytes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:6262-6271. [PMID: 32314580 DOI: 10.1021/acs.est.0c00624] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Tetrabromobisphenol A (TBBPA), the most widely used brominated flame retardant, is reported to potentially possess risks in inducing obesity or obesity-related metabolic diseases. Considering the increasing environmental contamination of TBBPA analogues and their high structural similarities to the parent compound, whether they could influence adipogenesis or not remains to be elucidated. In this study, two of the most prevalent TBBPA derivatives [i.e., TBBPA bis(allyl ether) (TBBPA-BAE) and TBBPA bis(2,3-dibromopropyl ether) (TBBPA-BDBPE)] and their byproducts [i.e., TBBPA mono(allyl ether) (TBBPA-MAE) and TBBPA mono(2,3-dibromopropyl ether) (TBBPA-MDBPE)], together with TBBPA, were screened for their capacities in activating peroxisome proliferator-activated receptor-γ (PPARγ) and glucocorticoid receptor (GR), the key nuclear receptors involved in adipogenesis, and their structure-related effects on differentiation of 3T3-L1 preadipocytes were explored. The results indicated that the binding affinities of TBBPA and its analogues for the PPARγ ligand-binding domain (PPARγ-LBD) and GR, as well as their effects on PPARγ transactivation, followed the order of TBBPA > TBBPA-MAE > TBBPA-MDBPE > TBBPA-BAE, TBBPA-BDBPE. Nevertheless, TBBPA-MAE and TBBPA-MDBPE showed higher potentials in promoting adipogenesis in 3T3-L1 cells than did TBBPA, as evidenced by intracellular triglyceride contents and adipogenic biomarkers at both protein and transcriptional levels. The etherified group at position 4 of TBBPA phenolic rings was crucial in chemical-induced adipogenic effects, which was related with the recruitment of PPARγ and GR-mediated networks and some other unidentified signaling pathways. The findings on the disturbance of TBBPA analogues on adipogenesis revealed their potential risk in causing obesity and other lipid metabolism-related human health concerns.
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Affiliation(s)
- Qian S Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P. R. China
| | - Zhendong Sun
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P. R. China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Xiaomin Ren
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P. R. China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Zhihua Ren
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P. R. China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Aifeng Liu
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, P. R. China
| | - Jianqing Zhang
- Department of POPs Lab, Shenzhen Center for Disease Control and Prevention, Shenzhen 518055, P. R. China
| | - Qunfang Zhou
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P. R. China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- School of Environment, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310000, P.R. China
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P. R. China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- School of Environment, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310000, P.R. China
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10
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AnvariFar H, Amirkolaie AK, Jalali AM, Miandare HK, Sayed AH, Üçüncü Sİ, Ouraji H, Ceci M, Romano N. Environmental pollution and toxic substances: Cellular apoptosis as a key parameter in a sensible model like fish. AQUATIC TOXICOLOGY 2018; 204:144-159. [PMID: 30273782 DOI: 10.1016/j.aquatox.2018.09.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 08/06/2018] [Accepted: 09/17/2018] [Indexed: 02/07/2023]
Abstract
The industrial wastes, sewage effluents, agricultural run-off and decomposition of biological waste may cause high environmental concentration of chemicals that can interfere with the cell cycle activating the programmed process of cells death (apoptosis). In order to provide a detailed understanding of environmental pollutants-induced apoptosis, here we reviewed the current knowledge on the interactions of environmental chemicals and programmed cell death. Metals (aluminum, arsenic, cadmium, chromium, cobalt, zinc, copper, mercury and silver) as well as other chemicals including bleached kraft pulp mill effluent (BKME), persistent organic pollutants (POPs), and pesticides (organo-phosphated, organo-chlorinated, carbamates, phyretroids and biopesticides) were evaluated in relation to apoptotic pathways, heat shock proteins and metallothioneins. Although research performed over the past decades has improved our understanding of processes involved in apoptosis in fish, yet there is lack of knowledge on associations between environmental pollutants and apoptosis. Thus, this review could be useful tool to study the cytotoxic/apoptotic effects of different pollutants in fish species.
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Affiliation(s)
- Hossein AnvariFar
- Department of Fisheries, Faculty of Animal Science and Fisheries, University of Agriculture and Natural Resources, P.O. Box 578, Sari, Iran; University of Applied Science and Technology, Provincial Unit, P.O. Box: 4916694338, Golestan, Iran
| | - A K Amirkolaie
- Department of Fisheries, Faculty of Animal Science and Fisheries, University of Agriculture and Natural Resources, P.O. Box 578, Sari, Iran
| | - Ali M Jalali
- Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, 49138-15739, Iran; Sturgeon Affairs Management, Gorgan, Golestan, Iran; Center for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, VIC, 3280, Australia
| | - H K Miandare
- Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, 49138-15739, Iran
| | - Alaa H Sayed
- Department of Zoology, Faculty of Science, Assiut University, 71516 Assiut, Egypt
| | - Sema İşisağ Üçüncü
- Department of Biology, Faculty of Science, Ege University, Bornova, 35100, İzmir, Turkey
| | - Hossein Ouraji
- Department of Fisheries, Faculty of Animal Science and Fisheries, University of Agriculture and Natural Resources, P.O. Box 578, Sari, Iran
| | - Marcello Ceci
- Department Ecological and Biological Sciences, University of Tuscia, Tuscia University, Viterbo, 01100, Italy
| | - Nicla Romano
- Department Ecological and Biological Sciences, University of Tuscia, Tuscia University, Viterbo, 01100, Italy.
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The chemical cue tetrabromopyrrole induces rapid cellular stress and mortality in phytoplankton. Sci Rep 2018; 8:15498. [PMID: 30341338 PMCID: PMC6195506 DOI: 10.1038/s41598-018-33945-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/04/2018] [Indexed: 02/08/2023] Open
Abstract
Eukaryotic phytoplankton contribute to the flow of elements through marine food webs, biogeochemical cycles, and Earth's climate. Therefore, how phytoplankton die is a critical determinate of the flow and fate of nutrients. While heterotroph grazing and viral infection contribute to phytoplankton mortality, recent evidence suggests that bacteria-derived cues also control phytoplankton lysis. Here, we report exposure to nanomolar concentrations of 2,3,4,5-tetrabromopyrrole (TBP), a brominated chemical cue synthesized by marine γ-proteobacteria, resulted in mortality of seven phylogenetically-diverse phytoplankton species. A comparison of nine compounds of marine-origin containing a range of cyclic moieties and halogenation indicated that both a single pyrrole ring and increased bromination were most lethal to the coccolithophore, Emiliania huxleyi. TBP also rapidly induced the production of reactive oxygen species and the release of intracellular calcium stores, both of which can trigger the activation of cellular death pathways. Mining of the Ocean Gene Atlas indicated that TBP biosynthetic machinery is globally distributed throughout the water column in coastal areas. These findings suggest that bacterial cues play multiple functions in regulating phytoplankton communities by inducing biochemical changes associated with cellular death. Chemically-induced lysis by bacterial infochemicals is yet another variable that must be considered when modeling oceanic nutrient dynamics.
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12
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Zota AR, Geller RJ, Romano LE, Coleman-Phox K, Adler NE, Parry E, Wang M, Park JS, Elmi AF, Laraia BA, Epel ES. Association between persistent endocrine-disrupting chemicals (PBDEs, OH-PBDEs, PCBs, and PFASs) and biomarkers of inflammation and cellular aging during pregnancy and postpartum. ENVIRONMENT INTERNATIONAL 2018; 115:9-20. [PMID: 29533840 PMCID: PMC5970048 DOI: 10.1016/j.envint.2018.02.044] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 01/31/2018] [Accepted: 02/25/2018] [Indexed: 05/18/2023]
Abstract
BACKGROUND Endocrine-disrupting chemicals (EDCs) can target immune and metabolic pathways. However, few epidemiologic studies have examined the influence of EDCs on measures of inflammation and cellular aging during pregnancy and postpartum. OBJECTIVE We investigated associations between prenatal exposures to polybrominated diphenyl ethers (PBDEs), hydroxylated PBDE metabolites (OH-PBDEs), polychlorinated biphenyls (PCBs), and per- and polyfluorochemicals (PFASs) with repeated biomarker measurements of inflammation and cellular aging in women during pregnancy and the postpartum period. METHODOLOGY Overweight or obese pregnant women were recruited from the San Francisco Bay area (n = 103) during their first or second trimester of pregnancy. Blood samples were collected from participants at baseline (median 16 weeks gestation) and at three and nine months postpartum. Serum concentrations of PBDEs, OH-PBDEs, PCBs, and PFASs were measured at baseline. Inflammation biomarkers (interleukin 6 [IL-6], interleukin 10 [IL-10], and tumor necrosis factor [TNF-α]) and leukocyte telomere length (LTL), a biomarker of cellular aging, were measured at all three time points. Associations between serum chemical concentrations and repeated measures of IL-6, IL-10, TNF-α, and LTL were examined using linear mixed models. We also examined the potential for effect modification by time (visit) and obesity. RESULTS In adjusted models, we observed positive relationships between PBDEs and pro-inflammatory cytokines (IL-6 and TNF-α). A doubling in ∑PBDEs was associated with a 15.26% (95% CI 1.24, 31.22) and 3.74% (95% CI -0.19, 7.82) increase in IL-6 and TNF-α, respectively. Positive associations were also observed for PFASs and IL-6. A two-fold increase in ∑PFASs was associated with a 20.87% (95% CI 3.46, 41.22) increase in IL-6. 5-OHBDE-47 was inversely associated with anti-inflammatory cytokine IL-10. Some EDC-outcome associations, including those of PBDEs with TNF-α, were stronger during pregnancy (compared to three or nine months postpartum) and among obese (compared to overweight) women (p-interaction <0.05). CONCLUSIONS These findings suggest that exposure to specific EDCs is associated with increased inflammation among women during pregnancy and the postpartum period. Future studies should replicate these findings in additional study populations and examine the implications of these associations for maternal and child health.
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Affiliation(s)
- Ami R Zota
- Milken Institute School of Public Health, The George Washington University, Washington, DC, USA.
| | - Ruth J Geller
- Milken Institute School of Public Health, The George Washington University, Washington, DC, USA
| | - Laura E Romano
- Milken Institute School of Public Health, The George Washington University, Washington, DC, USA
| | - Kimberly Coleman-Phox
- Center for Health and Community, School of Medicine, University of California, San Francisco, CA, USA
| | - Nancy E Adler
- Department of Psychiatry, School of Medicine, University of California, San Francisco, CA, USA
| | - Emily Parry
- Environmental Chemistry Laboratory, California Department of Toxic Substances Control, Berkeley, CA, USA
| | - Miaomiao Wang
- Environmental Chemistry Laboratory, California Department of Toxic Substances Control, Berkeley, CA, USA
| | - June-Soo Park
- Environmental Chemistry Laboratory, California Department of Toxic Substances Control, Berkeley, CA, USA
| | - Angelo F Elmi
- Milken Institute School of Public Health, The George Washington University, Washington, DC, USA
| | - Barbara A Laraia
- Division of Community Health and Human Development, School of Public Health, University of California, Berkeley, CA, USA
| | - Elissa S Epel
- Department of Psychiatry, School of Medicine, University of California, San Francisco, CA, USA
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13
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Félix LM, Vidal AM, Serafim C, Valentim AM, Antunes LM, Monteiro SM, Matos M, Coimbra AM. Ketamine induction of p53-dependent apoptosis and oxidative stress in zebrafish (Danio rerio) embryos. CHEMOSPHERE 2018; 201:730-739. [PMID: 29547861 DOI: 10.1016/j.chemosphere.2018.03.049] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 03/06/2018] [Accepted: 03/07/2018] [Indexed: 06/08/2023]
Abstract
Ketamine is a widely used pharmaceutical that has been detected in water sources worldwide. Zebrafish embryos were used in this study to investigate the oxidative stress and apoptotic signals following a 24h exposure to different ketamine concentrations (0, 50, 70 and 90 mg L-1). Early blastula embryos (∼2 h post fertilisation-hpf) were exposed for 24 h and analysed at 8 and 26 hpf. Reactive oxygen species and apoptotic cells were identified in vivo, at 26 hpf. Enzymatic activities (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), lactate dehydrogenase (LDH) and acetylcholinesterase (AChE)), glutathione levels (oxidised (GSSG) and reduced (GSH)), oxidative damage (lipid peroxidation (LPO) and protein carbonyls (CO)) as well as oxidative stress (gclc, gstp1, sod1 and cat), apoptosis (casp3a, casp6, casp8, casp9, aifm1 and tp53) and cell proliferation (pcna) related-genes were evaluated at 8 and 26 hpf. Caspase (3 and 9) activity was also determined at both time-points by colorimetric methods. Superoxide dismutase (SOD), catalase (CAT), glutathione levels (GSSG), caspase-9 and reactive oxygen species (ROS) were shown to be affected by ketamine exposure while in vivo analysis showed no difference in ROS. A significant up-regulation of superoxide dismutase (sod1) and catalase (cat) genes expression was also perceived. Ketamine-induced apoptosis was observed in vivo and confirmed by the apoptotic-related genes up-regulation. The overall results suggest that ketamine induced oxidative stress and apoptosis through the involvement of p53-dependent pathways in zebrafish embryos which could be important for the evaluation of the overall risk of ketamine in aquatic environments.
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Affiliation(s)
- Luís M Félix
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal; Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto (UP), Porto, Portugal; Laboratory Animal Science (LAS), Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto (UP), Porto, Portugal.
| | - Ana M Vidal
- Life Sciences and Environment School (ECVA), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
| | - Cindy Serafim
- Life Sciences and Environment School (ECVA), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
| | - Ana M Valentim
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal; Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto (UP), Porto, Portugal; Laboratory Animal Science (LAS), Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto (UP), Porto, Portugal
| | - Luís M Antunes
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal; Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto (UP), Porto, Portugal; Laboratory Animal Science (LAS), Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto (UP), Porto, Portugal; School of Agrarian and Veterinary Sciences (ECAV), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
| | - Sandra M Monteiro
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
| | - Manuela Matos
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal; Department of Genetics and Biotechnology (DGB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
| | - Ana M Coimbra
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), University of Trás-os-Montes and Alto Douro (UTAD), Vila Real, Portugal
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Saquib Q, Siddiqui MA, Ahmad J, Ansari SM, Al-Wathnani HA, Rensing C. 6-OHBDE-47 induces transcriptomic alterations of CYP1A1, XRCC2, HSPA1A, EGR1 genes and trigger apoptosis in HepG2 cells. Toxicology 2018; 400-401:40-47. [DOI: 10.1016/j.tox.2018.03.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 03/17/2018] [Accepted: 03/26/2018] [Indexed: 12/19/2022]
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15
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Wang F, Fang M, Hinton DE, Chernick M, Jia S, Zhang Y, Xie L, Dong W, Dong W. Increased coiling frequency linked to apoptosis in the brain and altered thyroid signaling in zebrafish embryos (Danio rerio) exposed to the PBDE metabolite 6-OH-BDE-47. CHEMOSPHERE 2018; 198:342-350. [PMID: 29421749 PMCID: PMC7006228 DOI: 10.1016/j.chemosphere.2018.01.081] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/13/2018] [Accepted: 01/16/2018] [Indexed: 05/04/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are a group of brominated flame retardants that are ubiquitously detected in the environment and associated with adverse health outcomes. 6-OH-BDE-47 is a metabolite of the flame retardant, 2,2',4,4'-Tetrabromodiphenyl ether (BDE-47), and there is increasing concern regarding its developmental neurotoxicity and endocrine disrupting properties. In this study, we report that early life exposure in zebrafish (Danio rerio) embryos to 6-OH-BDE-47 (50 and 100 nM) resulted in higher coiling frequency and significantly increased apoptotic cells in the brain. These effects were partially rescued by overexpression of thyroid hormone receptor β (THRβ) mRNA. Moreover, exposure to 100 nM 6-OH-BDE-47 significantly reduced the number of hypothalamic 5-hydroxytryptamine (5-HT, serotonin)-immunoreactive (5-HT-ir) neurons and the mRNA expression of tryptophan hydroxylase 2 (TPH2). These results indicate that 6-OH-BDE-47 affected thyroid hormone regulation through THRβ and negatively impacted the nervous system, in turn, affecting coiling behavior. Correlations of these endpoints suggest that coiling frequency could be used as an indicator of neurotoxicity in embryos.
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Affiliation(s)
- Feng Wang
- Inner Mongolia Key Laboratory of Toxicant Monitoring and Toxicology, Collage of Animal Science and Technology, Inner Mongolia University for Nationalities, Tongliao, Inner Mongolia, 028000, China
| | - Mingliang Fang
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - David E Hinton
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, United States
| | - Melissa Chernick
- Nicholas School of the Environment, Duke University, Durham, NC, 27708, United States
| | - Shenglan Jia
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Yingdan Zhang
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
| | - Lingtian Xie
- The Environmental Research Institute, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, Guangdong, 510006, China
| | - Wenjing Dong
- Inner Mongolia Key Laboratory of Toxicant Monitoring and Toxicology, Collage of Animal Science and Technology, Inner Mongolia University for Nationalities, Tongliao, Inner Mongolia, 028000, China
| | - Wu Dong
- Inner Mongolia Key Laboratory of Toxicant Monitoring and Toxicology, Collage of Animal Science and Technology, Inner Mongolia University for Nationalities, Tongliao, Inner Mongolia, 028000, China; Nicholas School of the Environment, Duke University, Durham, NC, 27708, United States.
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Lackmann C, Santos MM, Rainieri S, Barranco A, Hollert H, Spirhanzlova P, Velki M, Seiler TB. Novel procedures for whole organism detection and quantification of fluorescence as a measurement for oxidative stress in zebrafish (Danio rerio) larvae. CHEMOSPHERE 2018; 197:200-209. [PMID: 29366951 DOI: 10.1016/j.chemosphere.2018.01.045] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 01/10/2018] [Accepted: 01/11/2018] [Indexed: 06/07/2023]
Abstract
The modes of action of pollutants are diverse, and a common consequences to pollutant exposure is oxidative stress. This phenomenon is caused by an imbalance or disurption in the control of Reactive Oxygen Species (ROS) resulting in an accumulation of free radicals. Oxidative stress may cause damages to the DNA, phospholipids and proteins, and lead to cell death. Due to the possible contribution of oxidative stress to pollutant toxicity, it is valuable to assess its occurrence, role and mechanism. Detection of oxidative stress at low concentrations soon after the onset of exposure can be a sensitive, general marker for contamination. This study aimed at developing and benchmarking a set of novel fluorescence-based procedures to assess the occurrence of oxidative stress in zebrafish larvae (96 hpf) by measuring the antioxidant glutathione (GSH) and general ROS. Zebrafish larvae were exposed to tert-butyl hydroperoxide (t-BHP). ROS and GSH were made visible by means of specific fluorescent molecular probes in different experimental scenarios. The induction was qualified using microscopy and quantified through photometric measurement. For quantitative assessment, an approach based on homogenized larvae and a non-invasive plate assay were developed. The novel procedures proved suitable for oxidative stress detection. Comparisons of qualitative to quantitative data showed that the orientation of the larvae in the well can influence fluorescence data evaluation. The non-invasive quantitative assay proved robust against any influence of the orientation of the larvae. The developed protocols promise to be useful tools for the detection of oxidative stress in zebrafish larvae.
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Affiliation(s)
- Carina Lackmann
- RWTH Aachen University, Institute for Environmental Research, Worringerweg 1, 52074 Aachen, Germany
| | - Monica Martinez Santos
- AZTI, Food Research Division, Parque Tecnológico de Bizkaia, Astondo bidea 609, 48160 Derio, Spain
| | - Sandra Rainieri
- AZTI, Food Research Division, Parque Tecnológico de Bizkaia, Astondo bidea 609, 48160 Derio, Spain
| | - Alejandro Barranco
- AZTI, Food Research Division, Parque Tecnológico de Bizkaia, Astondo bidea 609, 48160 Derio, Spain
| | - Henner Hollert
- RWTH Aachen University, Institute for Environmental Research, Worringerweg 1, 52074 Aachen, Germany
| | | | - Mirna Velki
- Josip Juraj Strossmayer University in Osijek, Department of Biology, Cara Hadrijana 8/A, 31000 Osijek, Croatia
| | - Thomas-Benjamin Seiler
- RWTH Aachen University, Institute for Environmental Research, Worringerweg 1, 52074 Aachen, Germany.
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Dufour P, Pirard C, Charlier C. Determination of phenolic organohalogens in human serum from a Belgian population and assessment of parameters affecting the human contamination. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 599-600:1856-1866. [PMID: 28545212 DOI: 10.1016/j.scitotenv.2017.05.157] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 05/03/2017] [Accepted: 05/17/2017] [Indexed: 06/07/2023]
Abstract
Many in vitro or in vivo studies highlighted the potential deleterious effects of phenolic organohalogenated compounds (POHs) on the health, particularly on the thyroid system homeostasis, however few large scale human epidemiological studies have been carried out, especially in Europe. Further studies monitoring the human contamination by POHs, the sources of exposure and the influence of these compounds on thyroid health are still needed. Therefore we determined the concentrations of 16 POHs (pentachlorophenol (PCP), tetrabromobisphenol A (TBBPA), 4 bromophenols (BPs), 3 hydroxy-polybromodiphenylethers (OH-PBDEs) and 7 hydroxy-polychlorobiphenyls (OH-PCBs)) in serum from 274 people aged from 18 to 76years old living in Liege (Belgium) and the surrounding area. A questionnaire about their alimentary habits, life style and home environment was also administered to the volunteers. The predominant compound measured in the population was PCP (median concentration of 593.0pgmL-1). 4-OH-CB 107, 4-OH-CB 146 and 4-OH-CB 187 were detected in all samples and contributed for 75% of the sum of OH-PCBs (ΣOH-PCBs). The median measured in our population for ΣOH-PCBs was 143.7pgmL-1. TBBPA and 2,4,6-tribromophenol were detected in 31% and 63.8% of the samples respectively while the detection frequency observed for the other BPs and the OH-PBDEs was close to zero. We computed multivariate regression models in order to assess the influence of demographic and lifestyle parameters on the PCP and ΣOH-PCBs contamination levels. Significant correlation was found between the PCP concentration and sex, smoker status, sea fish consumption and level of education, although the model seemed to be a poor (R2=0.14) predictor of the PCP concentration. The model computed for ΣOH-PCBs was more explanatory (R2=0.61) and involved age, BMI and sea fish consumption. Finally, we assessed the parameters affecting the ΣOH-PCBs/ΣPCBs ratio. The model proposed involved age, BMI, smoker status and parent PCB level, and explained 41% of the variability of the ΣOH-PCBs/ΣPCBs ratio.
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Affiliation(s)
- Patrice Dufour
- Laboratory of Clinical, Forensic and Environmental Toxicology, University of Liege (ULg) CHU (B35), 4000, Liege, Belgium; Center for Interdisciplinary Research on Medicines (C.I.R.M.), University of Liege (ULg) CHU (B35), 4000, Liege, Belgium.
| | - Catherine Pirard
- Laboratory of Clinical, Forensic and Environmental Toxicology, University of Liege (ULg) CHU (B35), 4000, Liege, Belgium; Center for Interdisciplinary Research on Medicines (C.I.R.M.), University of Liege (ULg) CHU (B35), 4000, Liege, Belgium
| | - Corinne Charlier
- Laboratory of Clinical, Forensic and Environmental Toxicology, University of Liege (ULg) CHU (B35), 4000, Liege, Belgium; Center for Interdisciplinary Research on Medicines (C.I.R.M.), University of Liege (ULg) CHU (B35), 4000, Liege, Belgium
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18
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Kang HM, Lee YH, Kim BM, Kim IC, Jeong CB, Lee JS. Adverse effects of BDE-47 on in vivo developmental parameters, thyroid hormones, and expression of hypothalamus-pituitary-thyroid (HPT) axis genes in larvae of the self-fertilizing fish Kryptolebias marmoratus. CHEMOSPHERE 2017; 176:39-46. [PMID: 28254713 DOI: 10.1016/j.chemosphere.2017.02.081] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 02/13/2017] [Accepted: 02/14/2017] [Indexed: 06/06/2023]
Abstract
2,2',4,4'-tetrabromodiphenylether (BDE-47) is known to have the potential to disrupt the thyroid endocrine system in fishes due to its structural similarity to the thyroid hormones triiodothyronine (T3) and thyroxine (T4). However, the effects of BDE-47 on thyroid function in fishes remain unclear. In this study, abnormal development (e.g. deformity, hemorrhaging) and an imbalance in thyroid hormone (TH) homeostasis was shown in the early developmental stages of the mangrove killifish Kryptolebias marmoratus in response to BDE-47 exposure. To examine the thyroid endocrinal effect of BDE-47 exposure in mangrove killifish K. marmoratus larvae, transcript levels of genes involved in TH homeostasis and hypothalamus-pituitary-thyroid (HPT) axis-related genes were measured. The expression of thyroid hormone metabolism-related genes (e.g. deiodinases, UGT1ab) and HPT axis-related genes was up-regulated and there were significant changes in TH levels (P < 0.05) in response to BDE-47 exposure. This study provides insights into the regulation of TH homeostasis at the transcriptional level and provides a better understanding on the potential impacts of BDE-47 on the thyroid endocrine system of fishes.
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Affiliation(s)
- Hye-Min Kang
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Young Hwan Lee
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea
| | - Bo-Mi Kim
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea; Unit of Polar Genomics, Korea Polar Research Institute, Incheon 21990, South Korea
| | - Il-Chan Kim
- Division of Polar Life Sciences, Korea Polar Research Institute, Incheon 21990, South Korea
| | - Chang-Bum Jeong
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
| | - Jae-Seong Lee
- Department of Biological Science, College of Science, Sungkyunkwan University, Suwon 16419, South Korea.
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Effects of Hydroxylated Polybrominated Diphenyl Ethers in Developing Zebrafish Are Indicative of Disruption of Oxidative Phosphorylation. Int J Mol Sci 2017; 18:ijms18050970. [PMID: 28467386 PMCID: PMC5454883 DOI: 10.3390/ijms18050970] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/10/2017] [Accepted: 04/21/2017] [Indexed: 12/31/2022] Open
Abstract
Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) have been detected in humans and wildlife. Using in vitro models, we recently showed that OH-PBDEs disrupt oxidative phosphorylation (OXPHOS), an essential process in energy metabolism. The goal of the current study was to determine the in vivo effects of OH-PBDE reported in marine wildlife. To this end, we exposed zebrafish larvae to 17 OH-PBDEs from fertilisation to 6 days of age, and determined developmental toxicity as well as OXPHOS disruption potential with a newly developed assay of oxygen consumption in living embryos. We show here that all OH-PBDEs tested, both individually and as mixtures, resulted in a concentration-dependant delay in development in zebrafish embryos. The most potent substances were 6-OH-BDE47 and 6'-OH-BDE49 (No-Effect-Concentration: 0.1 and 0.05 µM). The first 24 h of development were the most sensitive, resulting in significant and irreversible developmental delay. All substances increased oxygen consumption, an effect indicative of OXPHOS disruption. Our results suggest that the induced developmental delay may be caused by disruption of OXPHOS. Though further studies are needed, our findings suggest that the environmental concentrations of some OH-PBDEs found in Baltic Sea wildlife in the Baltic Sea may be of toxicological concern.
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Uptake and biotransformation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) in four marine microalgae species. Sci Rep 2017; 7:44263. [PMID: 28287149 PMCID: PMC5347160 DOI: 10.1038/srep44263] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 02/07/2017] [Indexed: 11/30/2022] Open
Abstract
Hydroxylated- and methoxylated- polybrominated diphenyl ethers (OH-PBDEs and MeO-PBDEs) are more toxic than PBDEs and occur widely in the marine environment, and yet their origins remain controversial. In this study, four species of microalgae (Isochrysis galbana, Prorocentrum minimum, Skeletonema grethae and Thalassiosira pseudonana) were exposed to BDE-47, which is synthetic and is the predominant congener of PBDEs in the environment. By chemical analysis after incubation of 2 to 6 days, the efficiency of uptake of BDE-47 and, more importantly, the potential of undergoing biotransformation to form OH-PBDEs and MeO-PBDEs by the microalgae were investigated. Growth rates of these axenic microalgae were not affected upon exposure to environmentally relevant concentrations (0.2–20 μg BDE-47 L−1), and accumulation ranged from 0.772 ± 0.092 μg BDE-47 g−1 lipid to 215 ± 54 μg BDE-47 g−1 lipid within 2 days. Debromination of BDE-47 and formation of BDE-28 occurred in all microalgae species (0.01 to 0.87%), but biotransformation to OH-PBDEs was only found in I. galbana upon exposure to extremely high concentration. The results of this study showed that biotransformation of microalgae species is unlikely an explanation for the OH-PBDEs and MeO-PBDEs found in the marine environment.
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Macaulay LJ, Chernick M, Chen A, Hinton DE, Bailey JM, Kullman SW, Levin ED, Stapleton HM. Exposure to a PBDE/OH-BDE mixture alters juvenile zebrafish (Danio rerio) development. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2017; 36:36-48. [PMID: 27329031 PMCID: PMC5535307 DOI: 10.1002/etc.3535] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 04/08/2016] [Accepted: 06/18/2016] [Indexed: 05/03/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) and their metabolites (e.g., hydroxylated BDEs [OH-BDEs]) are contaminants frequently detected together in human tissues and are structurally similar to thyroid hormones. Thyroid hormones partially mediate metamorphic transitions between life stages in zebrafish, making this a critical developmental window that may be vulnerable to chemicals disrupting thyroid signaling. In the present study, zebrafish were exposed to 6-OH-BDE-47 (30 nM; 15 μg/L) alone, or to a low-dose (30 μg/L) or high-dose (600 μg/L) mixture of PentaBDEs, 6-OH-BDE-47 (0.5-6 μg/L), and 2,4,6-tribromophenol (5-100 μg/L) during juvenile development (9-23 d postfertilization) and evaluated for developmental endpoints mediated by thyroid hormone signaling. Fish were sampled at 3 time points and examined for developmental and skeletal morphology, apical thyroid and skeletal gene markers, and modifications in swimming behavior (as adults). Exposure to the high-dose mixture resulted in >85% mortality within 1 wk of exposure, despite being below reported acute toxicity thresholds for individual congeners. The low-dose mixture and 6-OH-BDE-47 groups exhibited reductions in body length and delayed maturation, specifically relating to swim bladder, fin, and pigmentation development. Reduced skeletal ossification was also observed in 6-OH-BDE-47-treated fish. Assessment of thyroid and osteochondral gene regulatory networks demonstrated significantly increased expression of genes that regulate skeletal development and thyroid hormones. Overall, these results indicate that exposures to PBDE/OH-BDE mixtures adversely impact zebrafish maturation during metamorphosis. Environ Toxicol Chem 2017;36:36-48. © 2016 SETAC.
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Affiliation(s)
- Laura J. Macaulay
- Nicholas School of the Environment, Duke University, Durham, NC 27708 USA
| | - Melissa Chernick
- Nicholas School of the Environment, Duke University, Durham, NC 27708 USA
| | - Albert Chen
- Nicholas School of the Environment, Duke University, Durham, NC 27708 USA
| | - David E. Hinton
- Nicholas School of the Environment, Duke University, Durham, NC 27708 USA
| | - Jordan M. Bailey
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710 USA
| | - Seth W. Kullman
- Department of Biological Sciences, NC State University, Raleigh, NC 27695 USA
| | - Edward D. Levin
- Nicholas School of the Environment, Duke University, Durham, NC 27708 USA
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710 USA
| | - Heather M. Stapleton
- Nicholas School of the Environment, Duke University, Durham, NC 27708 USA
- Corresponding author: Heather Stapleton, Nicholas School of the Environment, Duke University, Box 90328 LSRC A220, Durham, NC 27708, Phone: 919-613-8717, Fax: (919) 684-8741.,
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Yuan Y, Meeker JD, Ferguson KK. Serum polybrominated diphenyl ether (PBDE) concentrations in relation to biomarkers of oxidative stress and inflammation: The National Health and Nutrition Examination Survey 2003-2004. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 575:400-405. [PMID: 27750136 PMCID: PMC5164963 DOI: 10.1016/j.scitotenv.2016.10.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 10/03/2016] [Accepted: 10/04/2016] [Indexed: 05/08/2023]
Abstract
Exposure to polybrominated diphenyl ethers (PBDEs) has been associated with various adverse health outcomes related to liver, neural and endocrine systems. Some of these may be the result of PBDE-induced oxidative stress or inflammation, but these associations have been explored minimally in humans. In the present study we examined the relationship between PBDE concentrations and biomarkers of oxidative stress and inflammation measured in blood samples among a representative US sample from the National Health and Nutrition Examination Survey. Oxidative stress biomarkers showed no significant associations with PBDEs in adjusted regression models. For inflammation biomarkers, we observed small but statistically significant positive associations between BDE-153 and alkaline phosphatase (percent change with an interquartile range [IQR] increase in BDE-153=0.82, 95% confidence interval [CI]=0.01, 1.65) and absolute neutrophil count (percent change with IQR increase in BDE-153=0.53%, 95% CI=0.03, 1.04). Associations with other PBDE congeners and inflammation markers were generally positive but did not reach statistical significance. These results are consistent with human research of oxidative stress and inflammation in response to PBDE congeners and mixtures, and support previous reports of inflammation in response to PBDE treatment in animal and in vitro studies. More detailed toxicological and epidemiologic research in humans is needed to confirm the present results, and to determine the potential clinical and public health significance of these findings.
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Affiliation(s)
- Ye Yuan
- Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - John D Meeker
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI, USA
| | - Kelly K Ferguson
- Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI, USA; Epidemiology Branch, National Institute of Environmental Health Sciences, USA.
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Polybrominated diphenylethers (PBDEs) and their hydroxylated metabolites (OH-PBDEs) in female serum from Dalian, China. Int J Hyg Environ Health 2016; 219:816-822. [DOI: 10.1016/j.ijheh.2016.07.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 07/20/2016] [Accepted: 07/23/2016] [Indexed: 11/29/2022]
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24
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Marchitti SA, Mazur CS, Dillingham CM, Rawat S, Sharma A, Zastre J, Kenneke JF. Inhibition of the Human ABC Efflux Transporters P-gp and BCRP by the BDE-47 Hydroxylated Metabolite 6-OH-BDE-47: Considerations for Human Exposure. Toxicol Sci 2016; 155:270-282. [PMID: 28031414 DOI: 10.1093/toxsci/kfw209] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
High body burdens of polybrominated diphenyl ethers (PBDEs) in infants and young children have led to increased concern over their potential impact on human development. PBDE exposure can alter the expression of genes involved in thyroid homeostasis, including those of ATP-binding cassette (ABC) transporters, which mediate cellular xenobiotic efflux. However, little information exists on how PBDEs interact with ABC transporters such as P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP). The purpose of this study was to evaluate the interactions of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and its hydroxylated metabolite 6-OH-BDE-47 with P-gp and BCRP, using human MDR1- and BCRP-expressing membrane vesicles and stably transfected NIH-3T3-MDR1 and MDCK-BCRP cells. In P-gp membranes, BDE-47 did not affect P-gp activity; however, 6-OH-BDE-47 inhibited P-gp activity at low µM concentrations (IC50 = 11.7 µM). In BCRP membranes, BDE-47 inhibited BCRP activity; however, 6-OH-BDE-47 was a stronger inhibitor [IC50 = 45.9 µM (BDE-47) vs. IC50 = 9.4 µM (6-OH-BDE-47)]. Intracellular concentrations of known P-gp and BCRP substrates [(3H)-paclitaxel and (3H)-prazosin, respectively] were significantly higher (indicating less efflux) in NIH-3T3-MDR1 and MDCK-BCRP cells in the presence of 6-OH-BDE-47, but not BDE-47. Collectively, our results indicate that the BDE-47 metabolite 6-OH-BDE-47 is an inhibitor of both P-gp and BCRP efflux activity. These findings suggest that some effects previously attributed to BDE-47 in biological systems may actually be due to 6-OH-BDE-47. Considerations for human exposure are discussed.
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Affiliation(s)
- Satori A Marchitti
- U.S. Environmental Protection Agency, National Exposure Research Laboratory, Athens, Georgia 30605
| | - Christopher S Mazur
- U.S. Environmental Protection Agency, National Exposure Research Laboratory, Athens, Georgia 30605
| | - Caleb M Dillingham
- U.S. Environmental Protection Agency, National Exposure Research Laboratory, Athens, Georgia 30605
| | - Swati Rawat
- U.S. Environmental Protection Agency, National Exposure Research Laboratory, Athens, Georgia 30605
| | - Anshika Sharma
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, Georgia 30602
| | - Jason Zastre
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, Georgia 30602
| | - John F Kenneke
- U.S. Environmental Protection Agency, National Exposure Research Laboratory, Athens, Georgia 30605;
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25
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Usenko CY, Abel EL, Hopkins A, Martinez G, Tijerina J, Kudela M, Norris N, Joudeh L, Bruce ED. Evaluation of Common Use Brominated Flame Retardant (BFR) Toxicity Using a Zebrafish Embryo Model. TOXICS 2016; 4:E21. [PMID: 29051424 PMCID: PMC5606660 DOI: 10.3390/toxics4030021] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 08/16/2016] [Accepted: 08/16/2016] [Indexed: 11/16/2022]
Abstract
Brominated flame retardants (BFRs) are used to reduce the flammability of plastics, textiles, and electronics. BFRs vary in their chemical properties and structures, and it is expected that these differences alter their biological interactions and toxicity. Zebrafish were used as the model organism for assessing the toxicity of nine structurally-diverse BFRs. In addition to monitoring for overt toxicity, the rate of spontaneous movement, and acetylcholinesterase and glutathione-S-transferase (GST) activities were assessed following exposure. The toxicities of BFRs tested can be ranked by LC50 as tetrabromobisphenol A (TBBPA) < 4,4'-isopropylidenebis[2-(2,6-dibromophenoxyl)ethanol] (TBBPA-OHEE) < Pentabromochlorocyclohexane (PBCH) < 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB) < hexabromocyclododecane (HBCD) < hexabromobenzene (HBB) < Tetrabromophthalic anhydride (PHT4). No adverse effect was observed in di(2-ethylhexyl) tetrabromophthalate (TBPH) or dibromoneopentyl glycol (DBNPG)-treated embryos. The rate of spontaneous movement was decreased in a concentration-dependent manner following exposure to four of the nine compounds. GST activity was elevated following treatment with PBCH, TBBPA, HBCD, and HBB. The results indicate that exposure to several BFRs may activate an antioxidant response and alter behavior during early development. Some of the BFRs, such as TBBPA and TBBPA-OHEE, induced adverse effects at concentrations lower than chemicals that are currently banned. These results suggest that zebrafish are sensitive to exposure to BFRs and can be used as a comparative screening model, as well as to determine alterations in behavior following exposure and probe mechanisms of action.
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Affiliation(s)
- Crystal Y. Usenko
- Department of Biology, Baylor University, Waco, TX 76798, USA; (E.L.A.); (A.H.); (G.M.); (M.K.); (N.N.); (L.J.)
| | - Erika L. Abel
- Department of Biology, Baylor University, Waco, TX 76798, USA; (E.L.A.); (A.H.); (G.M.); (M.K.); (N.N.); (L.J.)
| | - Aaron Hopkins
- Department of Biology, Baylor University, Waco, TX 76798, USA; (E.L.A.); (A.H.); (G.M.); (M.K.); (N.N.); (L.J.)
| | - Gerardo Martinez
- Department of Biology, Baylor University, Waco, TX 76798, USA; (E.L.A.); (A.H.); (G.M.); (M.K.); (N.N.); (L.J.)
| | - Jonathan Tijerina
- Department of Biology, Baylor University, Waco, TX 76798, USA; (E.L.A.); (A.H.); (G.M.); (M.K.); (N.N.); (L.J.)
- School of Medicine, Stanford University, Palo Alto, CA 94305, USA;
| | - Molly Kudela
- Department of Biology, Baylor University, Waco, TX 76798, USA; (E.L.A.); (A.H.); (G.M.); (M.K.); (N.N.); (L.J.)
| | - Nick Norris
- Department of Biology, Baylor University, Waco, TX 76798, USA; (E.L.A.); (A.H.); (G.M.); (M.K.); (N.N.); (L.J.)
| | - Lana Joudeh
- Department of Biology, Baylor University, Waco, TX 76798, USA; (E.L.A.); (A.H.); (G.M.); (M.K.); (N.N.); (L.J.)
| | - Erica D. Bruce
- Department of Environmental Science, Baylor University, Waco, TX 76798, USA;
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26
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Díaz-Jaramillo M, Miglioranza KSB, Gonzalez M, Barón E, Monserrat JM, Eljarrat E, Barceló D. Uptake, metabolism and sub-lethal effects of BDE-47 in two estuarine invertebrates with different trophic positions. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 213:608-617. [PMID: 27017137 DOI: 10.1016/j.envpol.2016.03.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 03/02/2016] [Accepted: 03/02/2016] [Indexed: 06/05/2023]
Abstract
Two microcosm types -sediment-biota and biota-biota- were constructed to simulate different pathways of BDE-47 uptake, metabolism and oxidative stress effects in two key estuarine invertebrates (polychaete Laeonereis acuta and crab Cyrtograpsus angulatus). In the sediment-biota experiment, both species were exposed to spiked sediments; an environmentally reported and a high concentration of BDE-47 for 2 weeks. In the biota-biota experiment, crabs were fed with polychaetes pre-exposed to BDE-47 in the sediment-biota experiment. The sediment-biota experiment first revealed that polychaetes significantly accumulated BDE-47 (biota-sediment accumulation factor >2; p < 0.05) to a much greater extent than the crab organs (muscle, hepatopancreas, gills) at both sediment concentrations. For oxidative stress responses, polychaete and crab tissues exposed to spiked sediment showed a significant increase (p < 0.05) of only glutathione S-transferase (GST) activity with respect to controls in both BDE-47 concentrations. No lipid peroxidation (TBARS) or total antioxidant capacity (ACAP) changes were evident in the species or organs exposed to either BDE-47 sediment concentration. The biota-biota experiment showed that feeding crabs with pre-exposed polychaetes caused BDE-47 accumulation in organs as well as significant amounts of BDE-47 eliminated through feces (p < 0.05). Unlike the sediment-biota exposure, crabs fed with pre-exposed BDE-47 polychaetes showed the most conspicuous oxidative stress responses. Significant changes in GST and ACAP in both hepatopancreas and gills, in addition to enhanced TBARS levels in the hepatopancreas with respect to controls (p < 0.05), revealed that BDE-47 assimilated by invertebrates represents a potential source of toxicity to their predators. No methoxylated metabolites (MeO-PBDEs) were detected during BDE-47 metabolism in the invertebrates in either of the two different exposure types. In contrast, hydroxylated metabolites (OH-PBDEs) were detected in polychaetes and crab organs/feces in both experiments. Our results demonstrate that PBDE hydroxylation is one of the main biotransformation routes of BDE-47 in estuarine animals, which could be associated with the oxidative stress responses found.
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Affiliation(s)
- M Díaz-Jaramillo
- Laboratorio de Ecotoxicología y Contaminación Ambiental, Instituto de Investigaciones Marinas y Costeras (IIMyC), Universidad de Mar del Plata-CONICET, Argentina.
| | - K S B Miglioranza
- Laboratorio de Ecotoxicología y Contaminación Ambiental, Instituto de Investigaciones Marinas y Costeras (IIMyC), Universidad de Mar del Plata-CONICET, Argentina
| | - M Gonzalez
- Laboratorio de Ecotoxicología y Contaminación Ambiental, Instituto de Investigaciones Marinas y Costeras (IIMyC), Universidad de Mar del Plata-CONICET, Argentina
| | - E Barón
- Water and Soil Quality Research Group, Dep. of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - J M Monserrat
- Universidade Federal do Rio Grande - FURG, Instituto de Ciências Biológicas (ICB), Rio Grande, RS, Brazil
| | - E Eljarrat
- Water and Soil Quality Research Group, Dep. of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - D Barceló
- Water and Soil Quality Research Group, Dep. of Environmental Chemistry, IDAEA-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
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Deng D, Tam NFY. Adsorption-uptake-metabolism kinetic model on the removal of BDE-47 by a Chlorella isolate. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 212:290-298. [PMID: 26854698 DOI: 10.1016/j.envpol.2016.01.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Revised: 12/11/2015] [Accepted: 01/22/2016] [Indexed: 06/05/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are persistent and toxic organic pollutants, causing hazardous to ecosystems and human health but are difficult to remove from contaminated environments. The mechanism and kinetics of a Chlorella isolate to remove BDE-47 were investigated. This species isolated from the influent of wastewater treatment plants in Hong Kong was PBDE tolerant. More than 80% of BDE-47 was removed in short- and long-term experiments lasting 1 h and 7 days, respectively. The dominant removal process was adsorption on cell surfaces, with 73% of the spiked BDE-47 removed within five minutes of exposure. As the exposure prolonged, the adsorption became saturated. BDE-47 on cell surfaces was then gradually taken up into cells. At the end of the 7-day exposure, 17% of the spiked BDE-47 was within cells, while 27% was metabolized. Four metabolites, including BDE-28, 6-OH- and 5-OH-BDE-47, and 6-MeO-BDE-47, were produced from the debromination, hydroxylation and methoxylation of BDE-47. The removal kinetics of BDE-47 by freshwater microalgae could be explained by the multi-compartmental adsorption-uptake-metabolism model developed in this study.
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Affiliation(s)
- Dan Deng
- Department of Biology & Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon, Hong Kong, China
| | - Nora F Y Tam
- Department of Biology & Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon, Hong Kong, China; State Key Laboratory in Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Kowloon, Hong Kong, China.
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28
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Krieger LK, Szeitz A, Bandiera SM. Evaluation of hepatic biotransformation of polybrominated diphenyl ethers in the polar bear (Ursus maritimus). CHEMOSPHERE 2016; 146:555-564. [PMID: 26745384 DOI: 10.1016/j.chemosphere.2015.11.120] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 11/27/2015] [Accepted: 11/29/2015] [Indexed: 06/05/2023]
Abstract
Polar bears are at the top of the Arctic marine food chain and are subject to exposure and bioaccumulation of environmental chemicals of concern such as polybrominated diphenyl ethers (PBDEs), which were widely used as flame retardants. The aim of the present study was to evaluate the in vitro oxidative metabolism of 2,2',4,4'-tetrabrominated diphenyl ether (BDE-47) and 2,2',4,4',5-pentabrominated diphenyl ether (BDE-99) by polar bear liver microsomes. The identification and quantification of the hydroxy-brominated diphenyl ethers formed were assessed using an ultra-high performance liquid chromatography-tandem mass spectrometry-based method. Incubation of BDE-47 with archived individual liver microsomes, prepared from fifteen polar bears from northern Canada, produced a total of eleven hydroxylated metabolites, eight of which were identified using authentic standards. The major metabolites were 4'-hydroxy-2,2',4,5'-tetrabromodiphenyl ether and 5'-hydroxy-2,2',4,4'-tetrabromodiphenyl ether. Incubation of BDE-99 with polar bear liver microsomes produced a total of eleven hydroxylated metabolites, seven of which were identified using authentic standards. The major metabolites were 2,4,5-tribromophenol and 4-hydroxy-2,2',3,4',5-pentabromodiphenyl ether. Among the CYP specific antibodies tested, anti-rat CYP2B was found to be the most active in inhibiting the formation of hydroxylated metabolites of both BDE-47 and BDE-99, indicating that CYP2B was the major CYP enzyme involved in the oxidative biotransformation of these two congeners. Our study shows that polar bears are capable of forming multiple hydroxylated metabolites of BDE-47 and BDE-99 in vitro and demonstrates the role of CYP2B in the biotransformation and possibly in the toxicity of BDE-47 and BDE-99 in polar bears.
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Affiliation(s)
- Lisa K Krieger
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - András Szeitz
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Stelvio M Bandiera
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
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Dahlberg AK, Bignert A, Legradi J, Legler J, Asplund L. Anthropogenic and naturally produced brominated substances in Baltic herring (Clupea harengus membras) from two sites in the Baltic Sea. CHEMOSPHERE 2016; 144:2408-2414. [PMID: 26613358 DOI: 10.1016/j.chemosphere.2015.10.134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 10/23/2015] [Accepted: 10/31/2015] [Indexed: 06/05/2023]
Abstract
In the eutrophicated Baltic Sea, several naturally produced hydroxylated polybrominated diphenyl ethers (OH-PBDEs) have been found in marine biota. OH-PBDEs are toxic to adult and developing zebrafish and shown to be potent disruptors of oxidative phosphorylation (OXPHOS). Disturbed OXPHOS can result in altered energy metabolism and weight loss. In herring, the concentration of OH-PBDEs (i.e. 2'-OH-BDE68 and 6-OH-BDE47) has increased during the period 1980-2010 in the Baltic Proper. Over the same time period, the condition and fat content in Baltic herring have decreased. Given the toxicity and increasing trends of OH-PBDEs in Baltic herring it is important to further assess the exposure to OH-PBDEs in Baltic herring. In this study, the concentrations of OH-PBDEs and related brominated substances i.e. polybrominated phenols (PBPs), polybrominated anisoles (PBAs), methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and polybrominated diphenyl ethers (PBDEs) were measured in herring sampled in the northern Baltic Proper (Askö, n = 12) and the southern Bothnian Sea (Ängskärsklubb, n = 12). The geometric mean (GM) concentrations (ng/g l.w.) at Askö and Ängskärsklubb were; Σ2PBPs: 4.3 and 9.6, Σ(2)PBAs: 34 and 20, Σ(6)OH-PBDEs: 9.4 and 10, Σ(7)MeO-PBDEs: 42 and 150, Σ(6)PBDEs: 54 and 27, respectively. 6-OH-BDE47 dominated the OH-PBDE profile and comprised 87% (Askö) and 91% (Ängskärsklubb) of the ΣOH-PBDEs. At Ängskärsklubb the mean concentration of ΣMeO-PBDEs (150 ng/g l.w.) was 15 times higher than ΣOH-PBDEs. As other fish species are known to metabolically transform MeO-PBDEs to OH-PBDEs, high levels of MeO-PBDEs can be of concern as a precursor for more toxic OH-PBDEs in herring and their roe.
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Affiliation(s)
- Anna-Karin Dahlberg
- Analytical and Toxicological Unit, Department of Environmental Science and Analytical Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Anders Bignert
- Contaminant Research Group, Swedish Museum of Natural History, Box 50007, 104 05 Stockholm, Sweden
| | - Jessica Legradi
- Institute for Environmental Studies, VU University Amsterdam, De Boelelaan 1087, 1081 HV Amsterdam, The Netherlands
| | - Juliette Legler
- Institute for Environmental Studies, VU University Amsterdam, De Boelelaan 1087, 1081 HV Amsterdam, The Netherlands
| | - Lillemor Asplund
- Analytical and Toxicological Unit, Department of Environmental Science and Analytical Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden.
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30
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Dahlgren E, Lindqvist D, Dahlgren H, Asplund L, Lehtilä K. Trophic transfer of naturally produced brominated aromatic compounds in a Baltic Sea food chain. CHEMOSPHERE 2016; 144:1597-604. [PMID: 26517387 DOI: 10.1016/j.chemosphere.2015.10.024] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 10/04/2015] [Accepted: 10/05/2015] [Indexed: 05/26/2023]
Abstract
Brominated aromatic compounds (BACs) are widely distributed in the marine environment. Some of these compounds are highly toxic, such as certain hydroxylated polybrominated diphenyl ethers (OH-PBDEs). In addition to anthropogenic emissions through use of BACs as e.g. flame retardants, BACs are natural products formed by marine organisms such as algae, sponges, and cyanobacteria. Little is known of the transfer of BACs from natural producers and further up in the trophic food chain. In this study it was observed that total sum of methoxylated polybrominated diphenyl ethers (MeO-PBDEs) and OH-PBDEs increased in concentration from the filamentous red alga Ceramium tenuicorne, via Gammarus sp. and three-spined stickleback (Gasterosteus aculeatus) to perch (Perca fluviatilis). The MeO-PBDEs, which were expected to bioaccumulate, increased in concentration accordingly up to perch, where the levels suddenly dropped dramatically. The opposite pattern was observed for OH-PBDEs, where the concentration exhibited a general trend of decline up the food web, but increased in perch, indicating metabolic demethylation of MeO-PBDEs. Debromination was also indicated to occur when progressing through the food chain resulting in high levels of tetra-brominated MeO-PBDE and OH-PBDE congeners in fish, while some penta- and hexa-brominated congeners were observed to be the dominant products in the alga. As it has been shown that OH-PBDEs are potent disruptors of oxidative phosphorylation and that mixtures of different congener may act synergistically in terms of this toxic mode of action, the high levels of OH-PBDEs detected in perch in this study warrants further investigation into potential effects of these compounds on Baltic wildlife, and monitoring of their levels.
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Affiliation(s)
- Elin Dahlgren
- Legal Affairs, Swedish Environmental Protection Agency, SE-10648, Stockholm, Sweden
| | - Dennis Lindqvist
- Department of Environmental Science and Analytic Chemistry, Stockholm University, Sweden
| | - Henrik Dahlgren
- Department of Environmental Research and Monitoring, Swedish Museum of Natural History, Sweden
| | - Lillemor Asplund
- Department of Environmental Science and Analytic Chemistry, Stockholm University, Sweden.
| | - Kari Lehtilä
- The School of Natural Sciences, Technology and Environmental Studies, Södertörn University, Sweden
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31
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Félix LM, Vidal AM, Serafim C, Valentim AM, Antunes LM, Campos S, Matos M, Monteiro SM, Coimbra AM. Ketamine-induced oxidative stress at different developmental stages of zebrafish (Danio rerio) embryos. RSC Adv 2016. [DOI: 10.1039/c6ra08298j] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The changes induced by ketamine exposure were developmental stage-dependent, and related with the gradual development of the antioxidant defense system of the embryo, which is dependent on changes in energy-sensing pathways.
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Affiliation(s)
- Luís M. Félix
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
- Laboratory Animal Science (LAS)
| | - Ana M. Vidal
- Life Sciences and Environment School (ECVA)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
| | - Cindy Serafim
- Life Sciences and Environment School (ECVA)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
| | - Ana M. Valentim
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
- Laboratory Animal Science (LAS)
| | - Luís M. Antunes
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
- Laboratory Animal Science (LAS)
| | - Sónia Campos
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
- Laboratory Animal Science (LAS)
| | - Manuela Matos
- Biosystems & Integrative Sciences Institute (BioISI)
- Faculty of Sciences
- University of Lisboa
- Lisboa
- Portugal
| | - Sandra M. Monteiro
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
| | - Ana M. Coimbra
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB)
- University of Trás-os-Montes and Alto Douro (UTAD)
- Vila Real
- Portugal
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32
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Macaulay LJ, Chen A, Rock KD, Dishaw LV, Dong W, Hinton DE, Stapleton HM. Developmental toxicity of the PBDE metabolite 6-OH-BDE-47 in zebrafish and the potential role of thyroid receptor β. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2015; 168:38-47. [PMID: 26433919 PMCID: PMC4618599 DOI: 10.1016/j.aquatox.2015.09.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 09/14/2015] [Accepted: 09/15/2015] [Indexed: 05/13/2023]
Abstract
6-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (6-OH-BDE-47) is both a polybrominated diphenyl ether (PBDE) flame retardant metabolite and a marine natural product. It has been identified both as a neurotoxicant in cell-based studies and as a developmental toxicant in zebrafish. However, hydroxylated PBDE metabolites are also considered thyroid hormone disruptors due to their structural similarity to endogenous thyroid hormones. The purpose of this study was to evaluate the effects of 6-OH-BDE-47 on a developmental pathway regulated by thyroid hormones in zebrafish. Morphological measurements of development (head trunk angle, otic vesicle length, and eye pigmentation) were recorded in embryos at 30h post fertilization (hpf) and detailed craniofacial morphology was examined in 4 day old larvae using cartilage staining. Exposure to 6-OH-BDE-47 resulted in severe developmental delays. A 100nM concentration resulted in a 26% decrease in head trunk angle, a 54% increase in otic vesicle length, and a 42% decrease in eye pigmentation. Similarly, altered developmental morphology was observed following thyroid receptor β morpholino knockdown, exposure to the thyroid hormone triiodothyronine (T3) or to thyroid disrupting chemicals (TDC; iopanoic acid and propylthiouracil). The threshold for lower jaw deformities and craniofacial cartilage malformations was at doses greater than 50nM. Of interest, these developmental delays and effects were rescued by microinjection of TRβ mRNA during the 1-2 cell stage. These data indicate that OH-BDEs can adversely affect early life development of zebrafish and suggest they may be impacting thyroid hormone regulation in vivo through downregulation of the thyroid hormone receptor.
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Affiliation(s)
- Laura J Macaulay
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - Albert Chen
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - Kylie D Rock
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - Laura V Dishaw
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - Wu Dong
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - David E Hinton
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
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33
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Braunbeck T, Kais B, Lammer E, Otte J, Schneider K, Stengel D, Strecker R. The fish embryo test (FET): origin, applications, and future. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:16247-61. [PMID: 25395325 DOI: 10.1007/s11356-014-3814-7] [Citation(s) in RCA: 148] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 11/03/2014] [Indexed: 05/06/2023]
Abstract
Originally designed as an alternative for the acute fish toxicity test according to, e.g., OECD TG 203, the fish embryo test (FET) with the zebrafish (Danio rerio) has been optimized, standardized, and validated during an OECD validation study and adopted as OECD TG 236 as a test to assess toxicity of embryonic forms of fish. Given its excellent correlation with the acute fish toxicity test and the fact that non-feeding developmental stages of fish are not categorized as protected stages according to the new European Directive 2010/63/EU on the protection of animals used for scientific purposes, the FET is ready for use not only for range-finding but also as a true alternative for the acute fish toxicity test, as required for a multitude of national and international regulations. If-for ethical reasons-not accepted as a full alternative, the FET represents at least a refinement in the sense of the 3Rs principle. Objections to the use of the FET have mainly been based on the putative lack of biotransformation capacity and the assumption that highly lipophilic and/or high molecular weight substances might not have access to the embryo due to the protective role of the chorion. With respect to bioactivation, the only substance identified so far as not being activated in the zebrafish embryo is allyl alcohol; all other biotransformation processes that have been studied in more detail so far were found to be present, albeit, in some cases, at lower levels than in adult fish. With respect to larger molecules, the extension of the test duration to 96 h (i.e., beyond hatch) has-at least for the substances tested so far-compensated for the reduced access to the embryo; however, more research is necessary to fully explore the applicability of the FET to substances with a molecular weight >3 kDa as well as substances with a neurotoxic mode of action. An extension of the endpoints to also cover sublethal endpoints makes the FET a powerful tool for the detection of teratogenicity, dioxin-like activity, genotoxicity and mutagenicity, neurotoxicity, as well as various forms of endocrine disruption.
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Affiliation(s)
- Thomas Braunbeck
- Aquatic Ecology and Toxicology Group, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany.
| | - Britta Kais
- Aquatic Ecology and Toxicology Group, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany
| | - Eva Lammer
- Aquatic Ecology and Toxicology Group, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany
| | - Jens Otte
- Aquatic Ecology and Toxicology Group, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany
| | - Katharina Schneider
- Aquatic Ecology and Toxicology Group, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany
| | - Daniel Stengel
- Aquatic Ecology and Toxicology Group, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany
| | - Ruben Strecker
- Aquatic Ecology and Toxicology Group, Center for Organismal Studies, University of Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany
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34
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Macaulay LJ, Bailey JM, Levin ED, Stapleton HM. Persisting effects of a PBDE metabolite, 6-OH-BDE-47, on larval and juvenile zebrafish swimming behavior. Neurotoxicol Teratol 2015; 52:119-26. [PMID: 25979796 DOI: 10.1016/j.ntt.2015.05.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 04/30/2015] [Accepted: 05/04/2015] [Indexed: 12/09/2022]
Abstract
Polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants that are widely detected in the environment, biota, and humans. In mammals, PBDEs can be oxidatively metabolized to form hydroxylated polybrominated diphenyl ethers (OH-BDEs). While studies have examined behavioral deficits or alterations induced by exposure to PBDEs in both rodents and fish, no study to date has explored behavioral effects from exposure to OH-BDEs, which have been shown to have greater endocrine disrupting potential compared to PBDEs. In the present study, zebrafish (Danio rerio) were exposed during embryonic and larval development (0-6 days post fertilization, dpf) to a PBDE metabolite, 6-hydroxy, 2,2',4,4' tetrabromodiphenyl ether (10-50 nM) and then examined for short and long-term behavioral effects. Exposed zebrafish tested as larvae (6 dpf) showed an altered swimming response to light-dark transitions, exhibiting hypoactivity in light periods compared to control fish. When fish exposed from 0-6 dpf were tested as juveniles (45 dpf), they showed an increased fear response and hyperactivity in response to tests of novel environment exploration and habituation learning. These results demonstrate that early life exposure to a PBDE metabolite can have immediate or later life (more than a month after exposure) effects on activity levels, habituation, and fear/anxiety.
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Affiliation(s)
- Laura J Macaulay
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - Jordan M Bailey
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710, USA
| | - Edward D Levin
- Nicholas School of the Environment, Duke University, Durham, NC 27708, USA; Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710, USA
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35
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Usenko CY, Abel EL, Kudela M, Janise A, Bruce ED. Comparison of PBDE congeners as inducers of oxidative stress in zebrafish. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2015; 34:1154-1160. [PMID: 25663549 DOI: 10.1002/etc.2922] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 01/02/2015] [Accepted: 01/29/2015] [Indexed: 06/04/2023]
Abstract
A proposed primary pathway through which polybrominated diphenyl ethers (PBDEs) disrupt normal biological functions is oxidative stress. In the present study, 4 PBDE congeners were evaluated for their potential to initiate oxidative stress in zebrafish during development: BDE 28, BDE 47, BDE 99, and BDE 100. N-acetylcysteine (NAC) was used to increase intracellular glutathione concentrations and only decreased the effects of BDE 28 at 10 ppm and 20 ppm and BDE 47 at 20 ppm. N-acetylcysteine coexposure did not alter the rates of mortality or curved body axis compared with PBDE exposure alone. The activity of glutathione-S-transferase (GST) was not altered at 24 h postfertilization (hpf), but increased following 10 ppm BDE 28 exposure at 120 hpf. Transcription of several genes associated with stress was also evaluated. At 24 hpf, cytochrome c oxidase subunit 6a (COX6a) transcription was up-regulated in embryos exposed to BDE 99, and BDE 28 exposure up-regulated the transcription of Glutathione-S-transferase-pi (GSTpi). At 24 hpf, glutamate-cysteine ligase (GCLC) was slightly down-regulated by all congeners evaluated. At 120 hpf, TNF receptor-associated protein 1 (TRAP1) and COX6A were up-regulated by all congeners, however GSTpi was down-regulated by all congeners. The results of quantitative real-time transcription polymerase chain reaction are mixed and do not strongly support a transcriptional response to oxidative stress. According to the authors' data, PBDEs do not induce oxidative stress. Oxidative stress may occur at high exposure concentrations; however, this does not appear to be a primary mechanism of action for the PBDE congeners tested.
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36
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Liu H, Tang S, Zheng X, Zhu Y, Ma Z, Liu C, Hecker M, Saunders DMV, Giesy JP, Zhang X, Yu H. Bioaccumulation, biotransformation, and toxicity of BDE-47, 6-OH-BDE-47, and 6-MeO-BDE-47 in early life-stages of zebrafish (Danio rerio). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:1823-33. [PMID: 25565004 DOI: 10.1021/es503833q] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
2,2',4,4'-Tetrabromodiphenyl ether (BDE-47), 6-hydroxy-tetrabromodiphenyl ether (6-OH-BDE-47), and 6-methoxy-tetrabromodiphenyl ether (6-MeO-BDE-47) are the most detected congeners of polybrominated diphenyl ethers (PBDEs), OH-BDEs, and MeO-BDEs, respectively, in aquatic organisms. Although it has been demonstrated that BDE-47 can interfere with certain endocrine functions that are mediated through several nuclear hormone receptors (NRs), most of these findings were from mammalian cell lines exposed in vitro. In the present study, embryos and larvae of zebrafish were exposed to BDE-47, 6-OH-BDE-47, and 6-MeO-BDE-47 to compare their accumulation, biotransformation, and bioconcentration factors (BCF) from 4 to 120 hpf. In addition, effects on expression of genes associated with eight different pathways regulated by NRs were investigated at 120 hpf. 6-MeO-BDE-47 was most bioaccumulated and 6-OH-BDE-47, which was the most potent BDE, was least bioaccumulated. Moreover, the amount of 6-MeO-BDE-47, but not BDE-47, transformed to 6-OH-BDE-47 increased in a time-dependent manner, approximately 0.01%, 0.04%, and 0.08% at 48, 96, and 120 hpf, respectively. Expression of genes regulated by the aryl hydrocarbon receptor (AhR), estrogen receptor (ER), and mineralocorticoid receptor (MR) was affected in larvae exposed to 6-OH-BDE-47, whereas genes regulated by AhR, ER, and the glucocorticoid receptor (GR) were altered in larvae exposed to BDE-47. The greatest effect on expression of genes was observed in larvae exposed to 6-MeO-BDE-47. Specifically, 6-MeO-BDE-47 affected the expression of genes regulated by AhR, ER, AR, GR, and thyroid hormone receptor alpha (TRα). These pathways were mostly down-regulated at 2.5 μM. Taken together, these results demonstrate the importance of usage of an internal dose to assess the toxic effects of PBDEs. BDE-47 and its analogs elicited distinct effects on expression of genes of different hormone receptor-mediated pathways, which have expanded the knowledge of different mechanisms of endocrine disrupting effects in aquatic vertebrates. Because some of these homologues are natural products, assessments of risks of anthropogenic PBDE need to be made against the background of concentrations from naturally occurring products. Even though PBDEs are being phased out as flame retardants, the natural products remain.
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MESH Headings
- Animals
- Anisoles/pharmacokinetics
- Anisoles/toxicity
- Biotransformation
- Embryo, Nonmammalian/drug effects
- Embryo, Nonmammalian/metabolism
- Endocrine Disruptors/pharmacokinetics
- Endocrine Disruptors/toxicity
- Flame Retardants/pharmacokinetics
- Flame Retardants/toxicity
- Gene Expression Regulation, Developmental/drug effects
- Halogenated Diphenyl Ethers/pharmacokinetics
- Halogenated Diphenyl Ethers/toxicity
- Larva/drug effects
- Larva/genetics
- Larva/metabolism
- Polybrominated Biphenyls/pharmacokinetics
- Polybrominated Biphenyls/toxicity
- Receptors, Androgen/genetics
- Receptors, Aryl Hydrocarbon/genetics
- Receptors, Estrogen/genetics
- Receptors, Glucocorticoid/genetics
- Receptors, Mineralocorticoid/genetics
- Receptors, Thyroid Hormone/genetics
- Water Pollutants, Chemical/pharmacokinetics
- Water Pollutants, Chemical/toxicity
- Zebrafish/embryology
- Zebrafish/genetics
- Zebrafish/metabolism
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Affiliation(s)
- Hongling Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing, Jiangsu 210023, China
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37
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Yang J, Chan KM. Evaluation of the toxic effects of brominated compounds (BDE-47, 99, 209, TBBPA) and bisphenol A (BPA) using a zebrafish liver cell line, ZFL. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2015; 159:138-147. [PMID: 25544063 DOI: 10.1016/j.aquatox.2014.12.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 12/10/2014] [Accepted: 12/12/2014] [Indexed: 06/04/2023]
Abstract
The toxic effects of three polybrominated diphenyl ether (PBDE) congeners (BDE-47, -99, and -209), tetrabromobisphenol A (TBBPA) and bisphenol A (BPA), were evaluated by determining their 24h and 96 h median lethal concentrations using a zebrafish liver cell line, ZFL. It was found that BDE-47, BDE-99 and TBBPA showed comparative cytotoxicity within the range of 1.2-4.2 μM, and were more toxic than BPA (367.1 μM at 24 h and 357.6 μM at 96 h). However, BDE-209 induced only 15% lethality with exposures up to 25 μM. The molecular stresses of BDE-47, -99, TBBPA and BPA involved in thyroid hormone (TH) homeostasis and hepatic metabolism were also investigated. Using a reporter gene system to detect zebrafish thyroid hormone receptor β (zfTRβ) transcriptional activity, the median effective concentration of triiodothyronine (T3) was determined to be 9.2×10(-11) M. BDE-47, BDE-99, TBBPA and BPA alone, however, did not exhibit zfTRβ agonistic activity. BPA displayed T3 (0.1 nM) induced zfTRβ antagonistic activity with a median inhibitory concentration of 19.3 μM. BDE-47, BDE-99 and TBBPA displayed no antagonistic effects of T3-induced zfTRβ activity. Target gene expressions were also examined under acute exposures. The significant inhibition of different types of deiodinases by all of the test chemicals indicated TH circulation disruption. All four chemicals, especially BPA, were able to affect transcripts of phase II hepatic metabolizing enzymes (UGT2A1, SULT1) in vitro. In conclusion, the zfTRβ reporter gene system developed here helps delineate an in vitro model to enable the analysis of the TH disruption effects of environmental pollutants in fish. BPA and the brominated compounds tested were able to disrupt the TH system at the gene expression level, probably through the deiodination pathways.
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Affiliation(s)
- Jie Yang
- School of Life Sciences, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong Special Administrative Region
| | - King Ming Chan
- School of Life Sciences, The Chinese University of Hong Kong, Sha Tin, N.T., Hong Kong Special Administrative Region.
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38
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Qu BL, Yu W, Huang YR, Cai BN, Du LH, Liu F. 6-OH-BDE-47 promotes human lung cancer cells epithelial mesenchymal transition via the AKT/Snail signal pathway. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2015; 39:271-279. [PMID: 25531265 DOI: 10.1016/j.etap.2014.11.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Revised: 11/27/2014] [Accepted: 11/29/2014] [Indexed: 06/04/2023]
Abstract
Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) have been detected in the various human tissues. The OH-PBDEs are suggested to be stronger endocrine-disrupting compounds than PBDEs, therefore the toxicological effects of OH-PBDEs had received lots of attention. However, there is no study about the carcinogenic effect of OH-PBDEs and their estrogen potencies on the tumorigenesis and development of cancer. In the present study, we found that 6-hydroxy-2,2',4',4'-tetrabromodiphenyl ether (6-OH-BDE-47), the most abundant OH-PBDE congeners in human serum, promoted the in vitro migration of lung cancer A549 and H358 cells by induction of epithelial to mesenchymal transition (EMT). This was confirmed by that 6-OH-BDE-47 significantly down regulated the expression of epithelial markers E-cadherin (E-Cad) and zona occludin-1 (ZO-1) while up regulated the mesenchymal markers vimentin (Vim) and N-cadherin (N-Cad). 6-OH-BDE-47 up regulated the protein while not mRNA levels of Snail, which was the key transcription factor of EMT. Silencing of Snail by use of siRNA attenuated the 6-OH-BDE-47 induced EMT. This suggested that the stabilization of Snail was essential for 6-OH-BDE-47 induced EMT. Further, the treatment of 6-OH-BDE-47 increased the phosphorylation of AKT and ERK in A549 cells. Only PI3K/AKT inhibitor (LY294002), but not ERK inhibitor (PD98059), completely blocked the 6-OH-BDE-47 induced up regulation of Snail and down regulation of E-Cad, suggesting that PI3K/AKT pathway is important for 6-OH-BDE-47-mediated Snail stabilization and EMT in A549 cells. Generally, our results revealed for the first time that 6-OH-BDE-47 promoted the EMT of lung cancer cells via AKT/Snail signals. This suggested that more attention should be paid to the effects of OH-PBDEs on tumorigenesis and development of lung cancer.
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Affiliation(s)
- Bao-Lin Qu
- Department of Radiation Oncology, PLA General Hospital, Beijing 100853, China.
| | - Wei Yu
- Department of Radiation Oncology, PLA General Hospital, Beijing 100853, China
| | - Yu-Rong Huang
- Department of Radiation Oncology, PLA General Hospital, Beijing 100853, China
| | - Bo-Ning Cai
- Department of Radiation Oncology, PLA General Hospital, Beijing 100853, China
| | - Le-Hui Du
- Department of Radiation Oncology, PLA General Hospital, Beijing 100853, China
| | - Fang Liu
- Department of Radiation Oncology, PLA General Hospital, Beijing 100853, China
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39
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Legradi J, Dahlberg AK, Cenijn P, Marsh G, Asplund L, Bergman Å, Legler J. Disruption of oxidative phosphorylation (OXPHOS) by hydroxylated polybrominated diphenyl ethers (OH-PBDEs) present in the marine environment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:14703-11. [PMID: 25422162 DOI: 10.1021/es5039744] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) are of growing concern, as they have been detected in both humans and wildlife and have been shown to be toxic. Recent studies have indicated that OH-PBDEs can be more toxic than PBDEs, partly due to their ability to disrupt oxidative phosphorylation (OXPHOS), an essential process in energy metabolism. In this study, we determined the OXPHOS disruption potential of 18 OH-PBDE congeners reported in marine wildlife using two in vitro bioassays, namely the classic rat mitochondrial respiration assay, and a mitochondrial membrane potential assay using zebrafish PAC2 cells. Single OH-PBDE congeners as well as mixtures were tested to study potential additive or synergistic effects. An environmental mixture composed of seven OH-PBDE congeners mimicking the concentrations reported in Baltic blue mussels were also studied. We report that all OH-PBDEs tested were able to disrupt OXPHOS via either protonophoric uncoupling and/or inhibition of the electron transport chain. Additionally we show that OH-PBDEs tested in combinations as found in the environment have the potential to disrupt OXPHOS. Importantly, mixtures of OH-PBDEs may show very strong synergistic effects, stressing the importance of further research on the in vivo impacts of these compounds in the environment.
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Affiliation(s)
- Jessica Legradi
- Institute for Environmental Studies, VU University Amsterdam , De Boelelaan 1087, 1081 HV Amsterdam, The Netherlands
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40
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Jarque S, Piña B. Deiodinases and thyroid metabolism disruption in teleost fish. ENVIRONMENTAL RESEARCH 2014; 135:361-375. [PMID: 25462686 DOI: 10.1016/j.envres.2014.09.022] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 09/09/2014] [Accepted: 09/26/2014] [Indexed: 06/04/2023]
Abstract
Many xenobiotic compounds with endocrine disrupting activity have been described since the late eighties. These compounds are able to interact with natural hormone systems and potentially induce deleterious effects in wildlife, notably piscine species. However, while the characterization of endocrine disruptors with "dioxin-like", estrogenic or androgenic activities is relatively well established, little is known about environmentally relevant pollutants that may act at thyroid system level. Iodothyronine deiodinases, the key enzymes in the activation and inactivation of thyroid hormones, have been suggested as suitable biomarkers for thyroid metabolism disruption. The present article reviews the biotic and abiotic factors that are able to modulate deiodinases in teleosts, a representative model organism for vertebrates. Data show that deiodinases are highly sensitive to several physiological and physical variables, so they should be taken into account to establish natural basal deiodination patterns to further understand responses under chemical exposure. Among xenobiotic compounds, brominated flame retardants are postulated as chemicals of major concern because of their similar structure shared with thyroid hormones. More ambiguous results are shown for the rest of compounds, i.e. polychlorinated biphenyls, perfluorinated chemicals, pesticides, metals and synthetic drugs, in part due to the limited information available. The different mechanisms of action still remain unknown for most of those compounds, although several hypothesis based on observed effects are discussed. Future tasks are also suggested with the aim of moving forward in the full characterization of chemical compounds with thyroid disrupting activity.
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Affiliation(s)
- Sergio Jarque
- Masaryk University, Faculty of Science, RECETOX, Kamenice 5/753, CZ62500 Brno, Czech Republic.
| | - Benjamin Piña
- Institute of Environmental Assessment and Water Research, IDAEA-CSIC, Jordi Girona, 18, 08034 Barcelona, Spain.
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41
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Costa LG, de Laat R, Tagliaferri S, Pellacani C. A mechanistic view of polybrominated diphenyl ether (PBDE) developmental neurotoxicity. Toxicol Lett 2014; 230:282-94. [PMID: 24270005 PMCID: PMC4028440 DOI: 10.1016/j.toxlet.2013.11.011] [Citation(s) in RCA: 190] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 11/12/2013] [Indexed: 01/01/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs), extensively used in the past few decades as flame retardants in a variety of consumer products, have become world-wide persistent environmental pollutants. Levels in North America are usually higher than those in Europe and Asia, and body burden is 3-to-9-fold higher in infants and toddlers than in adults. The latter has raised concern for potential developmental toxicity and neurotoxicity of PBDEs. Experimental studies in animals and epidemiological observations in humans suggest that PBDEs may be developmental neurotoxicants. Pre- and/or post-natal exposure to PBDEs may cause long-lasting behavioral abnormalities, particularly in the domains of motor activity and cognition. The mechanisms underlying the developmental neurotoxic effects of PBDEs are not known, though several hypotheses have been put forward. One general mode of action relates to the ability of PBDEs to impair thyroid hormone homeostasis, thus indirectly affecting the developing brain. An alternative or additional mode of action involves a direct effect of PBDEs on nervous system cells; PBDEs can cause oxidative stress-related damage (DNA damage, mitochondrial dysfunction, apoptosis), and interfere with signal transduction (particularly calcium signaling), and with neurotransmitter systems. Important issues such as bioavailability and metabolism of PBDEs, extrapolation of results to low level of exposures, and the potential effects of interactions among PBDE congeners and between PBDEs and other contaminants also need to be taken into account.
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Affiliation(s)
- Lucio G Costa
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA; Department of Neuroscience, University of Parma, Parma, Italy.
| | - Rian de Laat
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
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42
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Chen X, Xu B, Han X, Mao Z, Chen M, Du G, Talbot P, Wang X, Xia Y. The effects of triclosan on pluripotency factors and development of mouse embryonic stem cells and zebrafish. Arch Toxicol 2014; 89:635-46. [PMID: 24879426 DOI: 10.1007/s00204-014-1270-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Accepted: 05/13/2014] [Indexed: 01/27/2023]
Abstract
Triclosan (TCS) poses potential risks to reproduction and development due to its endocrine-disrupting properties. However, the mechanism of TCS's effects on early embryonic development is little known. Embryonic stem cells (ESC) and zebrafish embryos provide valuable models for testing the toxic effects of environmental chemicals on early embryogenesis. In this study, mouse embryonic stem cells (mESC) were acutely exposed to TCS for 24 h, and general cytotoxicity and the effect of TCS on pluripotency were then evaluated. In addition, zebrafish embryos were exposed to TCS from 2- to 24-h post-fertilization (hpf), and their morphology was evaluated. In mESC, alkaline phosphatase staining was significantly decreased after treatment with the highest concentration of TCS (50 μM). Although the expression levels of Sox2 mRNA were not changed, the mRNA levels of Oct4 and Nanog in TCS-treated groups were significantly decreased compared to controls. In addition, the protein levels of Oct4, Sox2 and Nanog were significantly reduced in response to TCS treatment. MicroRNA (miR)-134, an expression inhibitor of pluripotency markers, was significantly increased in TCS-treated mESC. In zebrafish experiments, after 24 hpf of treatment, the controls had developed to the late stage of somitogenesis, while embryos exposed to 300 μg/L of TCS were still at the early stage of somitogenesis, and three genes (Oct4, Sox2 and Nanog) were upregulated in treated groups when compared with the controls. The two models demonstrated that TCS may affect early embryonic development by disturbing the expression of the pluripotency markers (Oct4, Sox2 and Nanog).
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Affiliation(s)
- Xiaojiao Chen
- State Key Laboratory of Reproductive Medicine, Nanjing Maternity and Child Health Hospital, Nanjing Medical University, Nanjing, 210029, China
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43
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Feo ML, Gonzalez O, Baron E, Casado M, Piña B, Esplugas S, Eljarrat E, Barceló D. Advanced UV/H₂O₂ oxidation of deca-bromo diphenyl ether in sediments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 479-480:17-20. [PMID: 24534697 DOI: 10.1016/j.scitotenv.2014.01.091] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 01/23/2014] [Accepted: 01/24/2014] [Indexed: 06/03/2023]
Abstract
Removal of BDE-209 from contaminated sediments by UV/H2O2 treatment was investigated under different reaction conditions (different UV irradiance and H2O2 concentrations). After 10h of UV/H2O2 treatment, 90% of BDE-209 was removed with a half-life time (t1/2) of 3.5h and a kinetic constant (k) of 0.22 h(-1). Possible formation of OH-PBDEs and debrominated polybromodiphenyl ethers was investigated by GC-MS and LC-MS/MS. None of the abovementioned BDE-209 by-products was found after 2.5, 5.5 and 10h of UV/H2O2 treatment. Toxicity experiments carried out with zebrafish embryos exposed to the sediment before and after the UV/H2O2 treatment did not show any morphological or behavioural alterations, suggesting that no putative debrominated or oxidation products were originated by the treatment in concentrations high enough to elicit significant toxic effects in zebrafish embryos.
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Affiliation(s)
- M L Feo
- Department of Environmental Chemistry, IDAEA, CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain; Department of Chemical Engineering, University of Barcelona, Marti i Franques, 1, 08082 Barcelona, Spain.
| | - O Gonzalez
- Department of Chemical Engineering, University of Barcelona, Marti i Franques, 1, 08082 Barcelona, Spain
| | - E Baron
- Department of Environmental Chemistry, IDAEA, CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - M Casado
- Department of Environmental Chemistry, IDAEA, CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - B Piña
- Department of Environmental Chemistry, IDAEA, CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - S Esplugas
- Department of Chemical Engineering, University of Barcelona, Marti i Franques, 1, 08082 Barcelona, Spain
| | - E Eljarrat
- Department of Environmental Chemistry, IDAEA, CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - D Barceló
- Department of Environmental Chemistry, IDAEA, CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain; Catalan Institute for Water Research (ICRA), Parc Científic i Tecnològic de la UdG (Edifici H(2)O), C/Emili Grahit 101, E-17003 Girona, Spain
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44
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Westerink RHS. Modulation of cell viability, oxidative stress, calcium homeostasis, and voltage- and ligand-gated ion channels as common mechanisms of action of (mixtures of) non-dioxin-like polychlorinated biphenyls and polybrominated diphenyl ethers. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:6373-6383. [PMID: 23686757 DOI: 10.1007/s11356-013-1759-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 04/22/2013] [Indexed: 06/02/2023]
Abstract
Non-dioxin-like polychlorinated biphenyls (NDL-PCBs) and polybrominated diphenyl ethers (PBDEs) are environmental pollutants that exert neurodevelopmental and neurobehavioral effects in vivo in humans and animals. Acute in vitro neurotoxic effects include changes in cell viability, oxidative stress, and basal intracellular calcium levels. Though these acute cellular effects could partly explain the observed in vivo effects, other mechanisms, such as effects on calcium influx and neurotransmitter receptor function, likely contribute to the disturbance in neurotransmission. This concise review combines in vitro data on cell viability, oxidative stress and basal calcium levels with recent data that clearly demonstrate that (hydroxylated) PCBs and (hydroxylated) PBDEs can exert acute effects on voltage-gated Ca(2+) channels as well as on excitatory and inhibitory neurotransmitter receptors in vitro. These novel mechanisms of action are shared by NDL-PCBs, OH-PBDEs, and some other persistent organic pollutants, such as tetrabromobisphenol-A, and could have profound effects on neurodevelopment, neurotransmission, and neurobehavior in vivo.
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Affiliation(s)
- Remco H S Westerink
- Neurotoxicology Research Group, Toxicology Division, Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, P.O. Box 80.177, 3508 TD, Utrecht, The Netherlands,
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45
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Rawat S, Bruce ED. Designing quantitative structure activity relationships to predict specific toxic endpoints for polybrominated diphenyl ethers in mammalian cells. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2014; 25:527-549. [PMID: 24738916 DOI: 10.1080/1062936x.2014.899512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are known as effective flame retardants and have vast industrial application in products like plastics, building materials and textiles. They are found to be structurally similar to thyroid hormones that are responsible for regulating metabolism in the body. Structural similarity with the hormones poses a threat to human health because, once in the system, PBDEs have the potential to affect thyroid hormone transport and metabolism. This study was aimed at designing quantitative structure-activity relationship (QSAR) models for predicting toxic endpoints, namely cell viability and apoptosis, elicited by PBDEs in mammalian cells. Cell viability was evaluated quantitatively using a general cytotoxicity bioassay using Janus Green dye and apoptosis was evaluated using a caspase assay. This study has thus modelled the overall cytotoxic influence of PBDEs at an early and a late endpoint by the Genetic Function Approximation method. This research was a twofold process including running in vitro bioassays to collect data on the toxic endpoints and modeling the evaluated endpoints using QSARs. Cell viability and apoptosis responses for Hep G2 cells exposed to PBDEs were successfully modelled with an r(2) of 0.97 and 0.94, respectively.
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Affiliation(s)
- S Rawat
- a Department of Environmental Science , Baylor University , Waco , TX , USA
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46
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González-Doncel M, Torija CF, Beltrán EM, García-Mauriño JE, Sastre S, Carbonell G. Limitations of waterborne exposure of fish early life stages to BDE-47. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2014; 148:184-194. [PMID: 24508762 DOI: 10.1016/j.aquatox.2014.01.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 12/10/2013] [Accepted: 01/15/2014] [Indexed: 06/03/2023]
Abstract
2,2',4,4'-Tetrabromodiphenyl ether (BDE-47) is acknowledged as the most abundant congener of all polybrominated diphenyl ethers (PBDEs). Despite its limited residence in the water column, most ecotoxicological research using fish early life stages (ELS) has focused on its waterborne bioavailability. These studies have been supported either by chemical analysis in solutions or in tissues after ≤ 168 h exposures to relatively high waterborne concentrations with dimethyl sulfoxide (DMSO) as solvent carrier (≤ 0.5%). Using noninvasive physiological and anatomical features in medaka ELS, we investigated the viability of waterborne BDE-47 exposures (100-10,000 μg/L; 1% DMSO) and evaluated the developmental effects in relation to the actual BDE-47 present in water. Embryos were exposed for 10 days under semi-static (24-h renewal) conditions and waterborne BDE-47 concentrations (i.e., dissolved) were quantitated daily and their accumulation in eleutheroembryonic tissues was analyzed 4 days after exposures finished. BDE-47 in solution rapidly decreased after each renewal by >50% in 24h. This was confirmed by discernible precipitation occurring at ≥ 5,000 μg/L on the bottom of the container and attached to the chorionic filaments of eggshell. The fast dissipation from water may explain why, besides the subtle, yet significant effects on post-hatching growth (short length at ≥5000μg/L), no other significant deleterious developmental effects were observed despite the fact that BDE-47 accumulated in tissues in response to BDE-47 treatment. Waterborne BDE-47 exposure was unachievable under traditional semi-static exposure conditions, but was achievable in repeated pulse exposures lasting a few hours whenever the medium was renewed. Hence, this research encourages the use of alternate - more realistic - exposure routes (e.g., particulate matter or sediments) when evaluating early developmental toxicity of BDE-47 or any other PBDE sharing similar properties.
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Affiliation(s)
- Miguel González-Doncel
- Laboratory for Ecotoxicology, Department of the Environment, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040 Madrid, Spain.
| | - Carlos Fernández Torija
- Laboratory for Ecotoxicology, Department of the Environment, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040 Madrid, Spain
| | - Eulalia María Beltrán
- Laboratory for Ecotoxicology, Department of the Environment, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040 Madrid, Spain
| | - José Enrique García-Mauriño
- Department of Cell Biology, School of Medicine, Complutense University, Ciudad Universitaria, E-28040 Madrid, Spain
| | - Salvador Sastre
- Laboratory of Forest Soils, Department of Forest Ecology, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040 Madrid, Spain
| | - Gregoria Carbonell
- Laboratory for Ecotoxicology, Department of the Environment, National Institute for Agricultural and Food Research and Technology, A-6, Km. 7.5, E-28040 Madrid, Spain
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47
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Montaño M, Weiss J, Hoffmann L, Gutleb AC, Murk AJ. Metabolic activation of nonpolar sediment extracts results in enhanced thyroid hormone disrupting potency. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:8878-8886. [PMID: 23786620 DOI: 10.1021/es4011898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Traditional sediment risk assessment predominantly considers the hazard derived from legacy contaminants that are present in nonpolar sediment extracts, such as polychlorinated biphenyls (PCBs), dioxins, furans (PCDD/Fs), and polyaromatic hydrocarbons (PAHs). Although in vivo experiments with these compounds have shown to be thyroid hormone disrupting (THD), in vitro their THD potency is not observed in nonpolar sediment extracts. This is hypothesized to be due to the absence of in vitro biotransformation which will result in bioactivation of the lipophilic compounds into THD hydroxyl metabolites. This study reveals that indeed metabolically activated nonpolar contaminants in sediments can competitively bind to thyroid hormone transport proteins. Sediment fractions were incubated with S9 rat microsomes, and the metabolites were extracted with a newly developed method that excludes most of the lipids to avoid interference in the applied nonradioactive 96-well plate TTR competitive binding assay. Metabolic activation increased the TTR binding potency of nonpolar fractions of POP-polluted sediments up to 100 times, resulting in potencies up to 240 nmol T4 equivalents/g sediment equivalent (nmol T4-Eq/g SEQ). This demonstrates that a more realistic in vitro sediment THD risk characterization should also include testing of both polar and medium polar sediment extracts for THD, as well as bioactivated nonpolar sediment fractions to prevent underestimation of its toxic potency.
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Affiliation(s)
- Mauricio Montaño
- Department of Environment and Agro-biotechnologies, Centre de Recherche Public-Gabriel Lippmann , 41, rue du Brill, L-4422 Belvaux, Grand Duchy of Luxembourg
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48
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Montaño M, Gutleb AC, Murk AJ. Persistent toxic burdens of halogenated phenolic compounds in humans and wildlife. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:6071-6081. [PMID: 23635024 DOI: 10.1021/es400478k] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Halogenated phenolic compounds (HPCs) including hydroxylated polychlorobiphenyls (OH-PCBs) and hydroxylated polybromodiphenyl-ethers (OH-PBDEs) can be persistent organic pollutant (POP) metabolites or natural marine compounds. Structurally similar to thyroid hormones (THs), they are retained in blood, transported through selective barriers, and the cause of endocrine and neuronal POP effects. This study presents a meta-analysis of HPC burdens in human and wildlife tissues, including OH-PCBs, OH-PBDEs, Pentachlorophenol, and polybromophenols. HPC blood plasma levels were also compared to known in vitro and in vivo toxicological effect concentrations. Blood, highly perfused, and fetal tissues contained the highest levels of HPCs. Plasma concentrations of analyzed OH-PCBs/PBDEs ranged from 0.1 to 100 nM in humans and up to 240, 454, 800, and 7650 nM for birds, fish, cetaceans, and other mammals, respectively. These concentrations fully fall within the in vitro effect concentrations reported in literature for HPCs of 0.05-10000 nM. We strongly advise further study of HPC blood levels in the general population, children, and fetal tissue to establish background levels and the risk at sensitive development stages. As not all HPCs are, or can be, chemically analyzed, the application of additional bioanalysis might reveal an even greater toxicological relevance of HPCs. In addition, metabolic activation should always be included within in vitro hazard assessment of POPs.
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Affiliation(s)
- Mauricio Montaño
- Centre de Recherche Public - Gabriel Lippmann, Department Environment and Agro-biotechnologies, 41 rue du Brill, L-4422 Belvaux, Grand Duchy of Luxembourg
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49
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Dong W, Macaulay L, Kwok KWH, Hinton DE, Stapleton HM. Using whole mount in situ hybridization to examine thyroid hormone deiodinase expression in embryonic and larval zebrafish: a tool for examining OH-BDE toxicity to early life stages. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2013; 132-133:190-9. [PMID: 23531416 PMCID: PMC3642849 DOI: 10.1016/j.aquatox.2013.02.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Revised: 02/11/2013] [Accepted: 02/13/2013] [Indexed: 05/20/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) and their oxidative metabolites (hydroxylated PBDEs; OH-BDEs) are known endocrine disrupting contaminants that have been shown to disrupt thyroid hormone regulation both in mammals and in fish. The purpose of this study was to determine the precise organ and tissue locations that express genes critical to thyroid hormone regulation in developing zebrafish (Danio rerio), and to determine the effects of an OH-BDE on their expression. While RT-PCR can provide quantitative data on gene expression, it lacks spatial sensitivity to examine localized gene expression; and, isolation of organs from zebrafish embryos is technically difficult, if not impossible. For this reason, the present study used whole mount in situ hybridization to simultaneously localize and quantify gene expression in vivo. While PBDEs and OH-BDEs have been shown to inhibit the activity and expression of deiodionases, a family of enzymes that regulate thyroid hormone concentrations intracellularly, it is unclear whether or not they can affect regional expression of the different isoforms during early development. In this study we investigated deiodinase 1 (Dio1), deiodinase 2 (Dio2), and deiodinase 3 (Dio3) mRNA expression at the following life stages (2, 8, and 1k-cells; 50%-epiboly, 6 and 18-somites, 22, 24, 48, 72 hpf and/or 10 dpf) in zebrafish and found life stage specific expression of these genes that were highly localized. To demonstrate the use of this technique for investigating potential endocrine disrupting effects, zebrafish embryos were exposed to 1, 10 and 100nM 6-OH-BDE-47. Significant increases in mean intensity of Dio1 and Dio3 expression in the periventricular zone of brain and pronephric duct, respectively (quantified by measuring intensity of coloration using ImageJ analysis software) were observed, suggesting localized response at the HPT axis with the possibility of impacting neurodevelopment. Our results demonstrate effects of OH-BDEs on thyroid regulating gene expression and provide more insight into potential sites of injury during early life stages.
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Affiliation(s)
- Wu Dong
- To whom correspondence should be addressed. Heather Stapleton, Phone: 919-613-8717, Fax: (919) 684-8741.
| | | | | | | | - Heather M. Stapleton
- To whom correspondence should be addressed. Heather Stapleton, Phone: 919-613-8717, Fax: (919) 684-8741.
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50
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Johnson LL, Anulacion BF, Arkoosh MR, Burrows DG, da Silva DA, Dietrich JP, Myers MS, Spromberg J, Ylitalo GM. Effects of Legacy Persistent Organic Pollutants (POPs) in Fish—Current and Future Challenges. FISH PHYSIOLOGY 2013. [DOI: 10.1016/b978-0-12-398254-4.00002-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
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