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Wu HD, Yang LW, Deng DY, Jiang RN, Song ZK, Zhou LT. The effects of brominated flame retardants (BFRs) on pro-atherosclerosis mechanisms. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 262:115325. [PMID: 37544066 DOI: 10.1016/j.ecoenv.2023.115325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 07/24/2023] [Accepted: 08/01/2023] [Indexed: 08/08/2023]
Abstract
Brominated flame-retardants (BFRs) are environmental endocrine disruptors, comprising several pollutants, which potentially affect the endocrine system and cause dysfunction and disease. Widespread BFR exposure may cause multisystem toxicity, including cardiovascular toxicity in some individuals. Studies have shown that BFRs not only increase heart rate, induce arrhythmia and cardiac hypertrophy, but also cause glycolipid metabolism disorders, vascular endothelial dysfunction, and inflammatory responses, all of which potentially induce pre-pathological changes in atherosclerosis. Experimental data indicated that BFRs disrupt gene expression or signaling pathways, which cause vascular endothelial dysfunction, lipid metabolism-related disease, inflammation, and possibly atherosclerosis. Considerable evidence now suggests that BFR exposure may be a pro-atherosclerotic risk factor. In this study, we reviewed putative BFR effects underpinning pro-atherosclerosis mechanisms, and focused on vascular endothelial cell dysfunction, abnormal lipid metabolism, pro-inflammatory cytokine production and foam cell formation. Consequently, we proposed a scientific basis for preventing atherosclerosis by BFRs and provided concepts for further research.
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Affiliation(s)
- Hai-Di Wu
- Department of Cardiology, The First Hospital of Jilin University, Changchun 130021, China
| | - Li-Wei Yang
- School of Public Health, Jilin University, Changchun 130021, China
| | - Da-Yong Deng
- Department of Radiology, Jilin Provincial Cancer Hospital, 1066 Jinhu Road, 130000 Changchun, China
| | - Rong-Na Jiang
- Department of Intensive Care Unit, Jilin Provincial Cancer Hospital, 1066 Jinhu Road, 130000 Changchun, China
| | - Zi-Kai Song
- Department of Cardiology, The First Hospital of Jilin University, Changchun 130021, China.
| | - Li-Ting Zhou
- School of Public Health, Jilin University, Changchun 130021, China.
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2
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Zhou Z, Chen H, Li Y, Liu Q, Lu K, Zhu X, Wang Y. Transcriptome and biochemical analyses of rainbow trout (Oncorhynchus mykiss) RTG-2 gonadal cells in response to BDE-47 stress indicates effects on cell proliferation. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2022; 245:106108. [PMID: 35189508 DOI: 10.1016/j.aquatox.2022.106108] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 02/03/2022] [Accepted: 02/06/2022] [Indexed: 06/14/2023]
Abstract
2,2',4,4'-Tetrabromodiphenyl ether (BDE-47) is a biotoxin of polybrominated diphenyl ether (PBDEs) frequently detected in the environment. Apoptosis and cell cycle arrest are important toxic phenomena of xenobiotics that inhibit cell proliferation. In this study, we investigated the effects of BDE-47 (5 μM, 10 μM, 20 μM, 40 μM) on cell viability, morphology, cell cycle and apoptosis. BDE-47 significantly decreased cell viability, and morphological alterations were observed. The significant increase in cells at G1 phase indicated the occurrence of G1 phase cell cycle arrest in RTG-2 cells. An acridine orange and ethidium bromide (AO/EB) staining assay was employed and revealed the induction of apoptosis in RTG-2 cells. The results indicated that BDE-47 exposure inhibits cell proliferation. Transcriptome analysis was applied for further evidence. A total of 1300 differentially expressed genes (DEGs) were identified in RTG-2 cells, among which 26 DEGs were associated with the cell cycle and apoptosis. Western blotting and qPCR analyses also showed the expression of cell cycle- and apoptosis-related proteins and genes. Mapping the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, p53, Tumor necrosis factor (TNF), Mitogen-activated protein kinase (MAPK), phosphatidylinositide 3-kinase-AKT (PI3K-AKT), and reaction oxygen species (ROS)-mediated signaling pathways were determined to be the major pathways involved in modulating the cell cycle and apoptosis. Since we demonstrated simultaneous ROS overproduction during BDE-47 exposure in a previous study, we speculated a possible explanation for the observation: BDE-47-induced ROS overproduction was the initiating signal, which activated cell cycle arrest and apoptosis and finally inhibited cell proliferation.
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Affiliation(s)
- Zhongyuan Zhou
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao, 266003, China.
| | - Hongmei Chen
- Key Laboratory of Xinjiang Endemic Phytomedicine Resources, Ministry of Education, Pharmacology Department, School of Pharmacy, Shihezi University, Shihezi, 832002, China.
| | - Yuanyuan Li
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao, 266003, China.
| | - Qian Liu
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao, 266003, China.
| | - Keyu Lu
- Department of Geography, University College London, London WC1E 6BT, UK.
| | - Xiaoshan Zhu
- Physiology and Toxicology, Graduate School of Shenzhen, Tsinghua University.
| | - You Wang
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao, 266003, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
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3
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Dungar BM, Schupbach CD, Jacobson JR, Kopf PG. Adrenal Corticosteroid Perturbation by the Endocrine Disruptor BDE-47 in a Human Adrenocortical Cell Line and Male Rats. Endocrinology 2021; 162:6346795. [PMID: 34370853 PMCID: PMC8402933 DOI: 10.1210/endocr/bqab160] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Indexed: 01/04/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) have been previously shown to alter various endocrine biosynthetic pathways. Growing epidemiological evidence suggests that PBDEs alter cardiovascular function. The goal of this study was to examine the effects of BDE-47 on adrenal corticosteroid pathways that play vital roles in cardiovascular homeostasis and pathophysiology. The effect of BDE-47 on aldosterone and cortisol secretion was characterized in a human adrenocortical cell line. HAC15 cells were exposed to various concentrations of BDE-47 (1 nM to 100 μM). Cell viability, corticosteroid secretion, gene expression of enzymes involved in corticosteroid synthesis, and metabolic activity was examined. Additionally, Sprague Dawley male rats were orally exposed to BDE-47 (10 or 100 µg/kg), 5 days per week for 16 weeks. Organ weights and plasma corticosteroid levels were measured. In HAC15 cells, basal and stimulated aldosterone and cortisol secretion was significantly increased by BDE-47. Gene expression of several enzymes involved in corticosteroid synthesis and mitochondrial metabolism also increased. In Sprague Dawley rats, adrenal but not heart, kidney, or liver weights, were significantly increased in BDE-47 treatment groups. Plasma corticosterone levels were significantly increased in the 100 µg BDE-47/kg treatment group. No change in plasma aldosterone levels were observed with BDE-47 exposure. These data indicate that BDE-47 disrupts the regulation of corticosteroid secretion and provides further evidence that PBDEs are potential endocrine disruptors. Future studies will determine the underlying molecular mechanism of altered corticosteroid production and examine whether these alterations result in underlying cardiovascular disease in our rodent model of 16-week BDE-47 exposure.
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Affiliation(s)
- Benjamin M Dungar
- Department of Pharmacology, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA
| | - Chad D Schupbach
- Department of Pharmacology, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA
| | - Jessie R Jacobson
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515, USA
| | - Phillip G Kopf
- Department of Pharmacology, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA
- Correspondence: Phillip G. Kopf, PhD, Department of Pharmacology, Midwestern University, 555 31st Street, Downers Grove, IL 60515, USA.
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Brito PM, Biscaia SMP, de Souza TL, Ramos AB, Leão-Buchir J, de Almeida Roque A, de Lima Bellan D, da Silva Trindade E, Filipak Neto F, de Oliveira Ribeiro CA. Oral exposure to BDE-209 modulates metastatic spread of melanoma in C57BL/6 mice inoculated with B16-F10 cells. CHEMOSPHERE 2020; 260:127556. [PMID: 32682134 DOI: 10.1016/j.chemosphere.2020.127556] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 06/26/2020] [Accepted: 06/28/2020] [Indexed: 06/11/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are brominated, persistent and bioaccumulative flame retardants widely used in the manufacture of plastic products. Decabromodiphenyl ether (BDE-209) is the most prevalent PBDE in the atmosphere and found in human blood, breast milk and umbilical cord. In vitro studies showed that BDE-209 interferes with murine melanoma cells (B16F10), modulating cell death rates, proliferation and migration, important events for cancer progression. In order to evaluate if BDE-209 modulates metastasis formation in murine models, C57BL/6 mice were exposed to BDE-209 (0.08, 0.8 and 8 μg⁄kg) via gavage (5-day intervals for 45 days) (9 doses in total). Then, mice were inoculated with melanoma cells (B16-F10) at caudal vein receiving 4 additional doses of BDE-209. At 20th day post-cell inoculation, blood, lung, liver, kidney and brain were sampled for hematological, biochemical and morphological analyses. The slightly higher levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the blood and pro-oxidant state in the liver of BDE-exposed mice indicated liver damage. Although the in vivo approach is for metastasis formation in the lung, they were unexpectedly observed in non-target organs (liver, brain, kidney and gonads). The similarity test showed high proximity among individuals from the control and a dissimilarity index between the control and exposed groups. The present data corroborate the known hepatotoxicity of BDE-209 to mice (C57BL/6) and demonstrate for the first time the increase of metastatic dissemination of B16F10 cells in vivo due to previous and continuous BDE-209 exposure, revealing possible implications of this organic compound with melanoma malignancy related traits.
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Affiliation(s)
- Patricia Manuitt Brito
- Laboratório de Toxicologia Celular, Departamento de Biologia Celular, Universidade Federal Do Paraná, CEP 81.531-980, Curitiba, Brazil
| | - Stellee Marcela Petris Biscaia
- Laboratório de Investigações de Polissacarídeos Sulfatados, Departamento de Biologia Celular, Universidade Federal Do Paraná, CEP 81.531-980, Curitiba, Brazil
| | - Tugstenio Lima de Souza
- Laboratório de Toxicologia Celular, Departamento de Biologia Celular, Universidade Federal Do Paraná, CEP 81.531-980, Curitiba, Brazil
| | - Amandia Batscheuer Ramos
- Laboratório de Toxicologia Celular, Departamento de Biologia Celular, Universidade Federal Do Paraná, CEP 81.531-980, Curitiba, Brazil
| | - Joelma Leão-Buchir
- Laboratório de Toxicologia Celular, Departamento de Biologia Celular, Universidade Federal Do Paraná, CEP 81.531-980, Curitiba, Brazil
| | - Aliciane de Almeida Roque
- Laboratório de Toxicologia Celular, Departamento de Biologia Celular, Universidade Federal Do Paraná, CEP 81.531-980, Curitiba, Brazil
| | - Daniel de Lima Bellan
- Laboratório de Investigações de Polissacarídeos Sulfatados, Departamento de Biologia Celular, Universidade Federal Do Paraná, CEP 81.531-980, Curitiba, Brazil
| | - Edvaldo da Silva Trindade
- Laboratório de Investigações de Polissacarídeos Sulfatados, Departamento de Biologia Celular, Universidade Federal Do Paraná, CEP 81.531-980, Curitiba, Brazil
| | - Francisco Filipak Neto
- Laboratório de Toxicologia Celular, Departamento de Biologia Celular, Universidade Federal Do Paraná, CEP 81.531-980, Curitiba, Brazil
| | - Ciro Alberto de Oliveira Ribeiro
- Laboratório de Toxicologia Celular, Departamento de Biologia Celular, Universidade Federal Do Paraná, CEP 81.531-980, Curitiba, Brazil.
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Chen Y, Guo M, Liu R, Ma LQ, Cui X. Effects of novel brominated flame retardants and metabolites on cytotoxicity in human umbilical vein endothelial cells. CHEMOSPHERE 2020; 253:126653. [PMID: 32302898 DOI: 10.1016/j.chemosphere.2020.126653] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 03/23/2020] [Accepted: 03/29/2020] [Indexed: 06/11/2023]
Abstract
Novel brominated flame retardants (NBFRs) have been widely used and frequently detected in various environmental matrices. In this study, 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB), bis-(2-ethylhexyl) tetrabromophthalate (TBPH) and their metabolites (namely 2,3,4,5-tetra-bromo benzoic acid (TBBA) and mono(2-ethylhexyl) tetrabromophthalate (TBMEHP)) were exposed to human umbilical vein endothelial cells (HUVECs). Metabolites can induce stronger cytotoxicity than parent compounds with EC50 at 47.3 (TBBA), 8.6 μg/ml (TBMEHP) vs > 200 μg/mL for parent compounds. Gene expression of platelet endothelial cell adhesion molecule-1, the gene associated with blood platelet kinetics, was significantly induced under TBBA and TBMEHP exposure. The in vivo test was consistent with gene expression result that the number of platelets in mouse blood was significantly increased after gavaged with 0.8 μg/mL TBBA and TBMEHP. In addition, TBB or TBPH were exposed to mice via gavage, and higher concentrations of TBBA (4 h, 60.8 ± 12.9 ng/mL, 8 h, 69.4 ± 2.24 ng/mL) in mouse blood were found than those of TBMEHP (4 h, 17.2 ± 4.01 ng/mL, 8 h, 12.8 ± 3.20 ng/mL), indicating that TBB was more readily in vivo metabolized than TBPH. The in vivo metabolism of TBB and TBPH and the stronger toxicity of their metabolites underscore the potential risk through NBFR exposure and the importance of understanding NBFR metabolism process.
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Affiliation(s)
- Yi Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210046, China
| | - Mengfan Guo
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210046, China
| | - Rongyan Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210046, China
| | - Lena Q Ma
- Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
| | - Xinyi Cui
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210046, China.
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Zhou Z, Zhou B, Chen H, Tang X, Wang Y. Reactive oxygen species (ROS) and the calcium-(Ca 2+) mediated extrinsic and intrinsic pathways underlying BDE-47-induced apoptosis in rainbow trout (Oncorhynchus mykiss) gonadal cells. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 656:778-788. [PMID: 30530147 DOI: 10.1016/j.scitotenv.2018.11.306] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 11/18/2018] [Accepted: 11/20/2018] [Indexed: 06/09/2023]
Abstract
The brominated flame retardant, 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), is well documented to exert potential negative impacts on different marine biota. However, the responsible mechanism remains unknown. The rainbow trout gonadal cell line RTG-2 was used as a model, and the mechanism and pathway underlying BDE-47 (6, 12.5 and 25 μM)-induced apoptosis and toxicity were examined in vitro. Apoptosis occurred in the RTG-2 cells exposed to BDE-47 in a clear concentration-dependent manner. The morphology of the mitochondrial alterations was observed using transmission electron microscopy. BDE-47 exposure decreased the cellular mitochondrial membrane potential, increased the cytochrome c released into the cytoplasm and elevated Fas protein expression. The mRNA expressions of Fas-associated death domain-containing protein (FADD), CHOP and GRP78 were also elevated, and similar increases were found in the activities of intracellular caspase-8, caspase-12, caspase-9 and caspase-3. These results indicated that the mitochondrial, endoplasmic reticulum and death-receptor pathways were involved in apoptosis in RTG-2 cells following BDE-47 exposure. ROS and Ca2+ were responsible for these changes because their overproduction was detected prior to apoptosis. However, the addition of the ROS scavenger N-acetyl-l-cysteine (NAC) and the intracellular calcium chelator (acetoxymethyl)-1,2-bis-(o-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA-AM) did not significantly alleviate the apoptosis rate. The results of the present study show that BDE-47 exposure induced apoptosis in RTG-2 cells via ROS- and Ca2-mediated mitochondrial, endoplasmic reticulum and death-receptor apoptotic pathways.
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Affiliation(s)
- Zhongyuan Zhou
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China
| | - Bin Zhou
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China; Laboratory for Marine Ecology and Environmental Science, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China.
| | - Hongmei Chen
- Key Laboratory of Xinjiang Endemic Phytomedicine Resources, Ministry of Education, Pharmacology Department, School of Pharmacy, Shihezi University, Shihezi 832002, China
| | - Xuexi Tang
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China; Laboratory for Marine Ecology and Environmental Science, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China.
| | - You Wang
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China; Laboratory for Marine Ecology and Environmental Science, Pilot National Laboratory for Marine Science and Technology, Qingdao 266237, China.
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7
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Xing X, Kang J, Qiu J, Zhong X, Shi X, Zhou B, Wei Y. Waterborne exposure to low concentrations of BDE-47 impedes early vascular development in zebrafish embryos/larvae. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2018; 203:19-27. [PMID: 30071320 DOI: 10.1016/j.aquatox.2018.07.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 07/13/2018] [Accepted: 07/14/2018] [Indexed: 06/08/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are persistent flame retardants ubiquitously existing in various environment matrices. In spite of a recent reduction in use according to the phase-out policy, high levels of PBDEs are still found in both environmental and biological samples due to their persistent property and large-scale production over a long history. Developmental toxicity is a major health concern of PBDEs. However, the impact of PBDE exposure on vascular development remains poorly understood. In this study, we investigated the effect of low concentrations of 2,2',4,4'-Tetrabromodiphenyl ether (BDE-47), a predominant PBDE congener, in environmental matrices and biota, on early vascular development using zebrafish. Zebrafish embryos were continuously exposed to waterborne BDE-47 at 0.06, 0.2, 0.6 μM starting from 2 h post-fertilization (hpf). Fluorescent images of vasculatures in Tg(kdrl:eGFP) zebrafish were acquired using a confocal microscope. The results indicated that BDE-47 exposure had no effect on hatching rate, survival, body weight, body length or heart rate in the early stage within 72 hpf, whereas zebrafish exposed to BDE-47 exhibited impairments in the growth of multiple types of blood vessels. The percentage of completed intersegmental vessels (ISV) at 30 hpf decreased in embryos treated with BDE-47 in a dose-dependent fashion. BDE-47 exposure led to a slight decrease in the growth of common cardinal vein (CCV), while dramatically hindered CCV remodeling process reflected by the larger CCV area and wider ventral diameter. BDE-47 exposure significantly reduced sub-intestinal vessels (SIV) area as well as the vascularized yolk area in zebrafish larvae at 72 hpf. In addition, the expression of genes related to vascular growth and remodeling was markedly suppressed in BDE-47-exposed zebrafish. These findings demonstrate the adverse effects of BDE-47 on early vascular development, and confirm the vascular toxicity of PBDEs in vivo. The results indicate that developing vasculature in zebrafish is sensitive to BDE-47 exposure, and may serve as a powerful tool for the assessment of early exposure to PBDEs.
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Affiliation(s)
- Xiumei Xing
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Jianmeng Kang
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Jiahuang Qiu
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Xiali Zhong
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Xiongjie Shi
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, The Insitute for Advanced Studies, Wuhan University, Wuhan 430072, China
| | - Bingsheng Zhou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yanhong Wei
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou 510080, China.
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Chen J, Li K, Le XC, Zhu L. Metabolomic analysis of two rice (Oryza sativa) varieties exposed to 2, 2', 4, 4'-tetrabromodiphenyl ether. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 237:308-317. [PMID: 29499574 DOI: 10.1016/j.envpol.2018.02.027] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 02/07/2018] [Accepted: 02/08/2018] [Indexed: 06/08/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are toxic chemicals widely distributed in the environment, but few studies are available on their potential toxicity to rice at metabolic level. Therefore we exposed ten rice (Oryza sativa) varieties to 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), a predominant congener of PBDEs, in hydroponic solutions with different concentrations. Two varieties that showed different biological effects to BDE-47, YY-9 and LJ-7, were screened as sensitive and tolerant varieties according to changes of morphological and physiological indicators. Metabolic research was then conducted using gas chromatography-mass spectrometry combined with diverse analyses. Results showed that LJ-7 was more active in metabolite profiles and adopted more effective antioxidant defense machinery to protect itself against oxidative damages induced by BDE-47 than YY-9. For LJ-7, the contents of 13 amino acids and 24 organic acids, especially l-glutamic acid, beta-alanine, glycolic acid and glyceric acid were up-regulated significantly which contributed to scavenging reactive oxygen species. In the treatment of 500 μg/L BDE-47, the contents of these four metabolites increased by 33.6-, 19.3-, 10.6- and 10.2-fold, respectively. The levels of most saccharides (such as d-glucose, lactulose, maltose, sucrose and d-cellobiose) also increased by 1.7-12.4 fold which promoted saccharide-related biosynthesis metabolism. Elevation of tricarboxylic acid cycle and glyoxylate and dicarboxylate metabolism enhanced energy-producing processes. Besides, the contents of secondary metabolites, chiefly polyols and glycosides increased significantly to act on defending oxidative stress induced by BDE-47. In contrast, the levels of most metabolites decreased significantly for YY-9, especially those of 13 amino acids (by 0.9%-67.1%) and 19 organic acids (by 7.8%-70.0%). The positive metabolic responses implied LJ-7 was tolerant to BDE-47, while the down-regulation of most metabolites indicated the susceptible nature of YY-9. Since metabolic change might affect the yield and quality of rice, this study can provide useful reference for rice cultivation in PBDEs-polluted areas.
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Affiliation(s)
- Jie Chen
- Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang, 310058, China
| | - Kelun Li
- Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang, 310058, China
| | - X Chris Le
- Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, T6G 2G3, Canada
| | - Lizhong Zhu
- Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang, 310058, China.
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9
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Li M, Huo X, Pan Y, Cai H, Dai Y, Xu X. Proteomic evaluation of human umbilical cord tissue exposed to polybrominated diphenyl ethers in an e-waste recycling area. ENVIRONMENT INTERNATIONAL 2018; 111:362-371. [PMID: 29169793 DOI: 10.1016/j.envint.2017.09.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 08/17/2017] [Accepted: 09/19/2017] [Indexed: 02/05/2023]
Abstract
Parental exposure to polybrominated diphenyl ethers (PBDEs) is associated with adverse birth outcomes. This study aims to examine differentially-expressed protein profiles in umbilical cord tissue, derived from mothers exposed to PBDEs, and investigate candidate biomarkers to reveal the underlying molecular mechanisms. Umbilical cord samples were obtained from women residing in an electronic waste (e-waste) recycling area (Guiyu) and reference area (Haojiang) in China. The concentration of PBDEs in umbilical cord tissue was determined by gas chromatography and mass spectrometry (GC/MS). Isobaric tagging for relative and absolute quantification (iTRAQ)-based proteomic technology was conducted to analyze differentially-expressed protein profiles. The total PBDE concentration was approximately five-fold higher in umbilical cords from Guiyu than from Haojiang (median 71.92ng/g vs. 15.52ng/g lipid, P<0.01). Neonatal head circumference, body-mass index (BMI) and Apgar1 score were lower in Guiyu and negatively correlated with PBDE concentration (P<0.01). Proteomic analysis showed 697 proteins were differentially expressed in the e-waste-exposed group compared with the reference group. The differentially-expressed proteins were principally involved in antioxidant defense, apoptosis, cell structure and metabolism. Among them, catalase and glutathione S-transferase omega-1, were down-regulated, and cytochrome c was found to be up-regulated, changes which were further verified by enzyme-linked immunosorbent assays. These results suggest that an antioxidant imbalance and cell apoptosis in the umbilical cord following PBDE exposure is associated with neonatal birth outcomes.
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Affiliation(s)
- Minghui Li
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Xia Huo
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Yukui Pan
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Haoxing Cai
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Yifeng Dai
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Xijin Xu
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, Guangdong, China; Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, China.
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Wong S, Napoli E, Krakowiak P, Tassone F, Hertz-Picciotto I, Giulivi C. Role of p53, Mitochondrial DNA Deletions, and Paternal Age in Autism: A Case-Control Study. Pediatrics 2016; 137:peds.2015-1888. [PMID: 27033107 PMCID: PMC4811307 DOI: 10.1542/peds.2015-1888] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/06/2016] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND The tumor suppressor p53 responds to a variety of environmental stressors by regulating cell cycle arrest, apoptosis, senescence, DNA repair, bioenergetics and mitochondrial DNA (mtDNA) copy number maintenance. Developmental abnormalities have been reported in p53-deficient mice, and altered p53 and p53-associated pathways in autism (AU). Furthermore, via the Pten-p53 crosstalk, Pten haploinsufficient-mice have autisticlike behavior accompanied by brain mitochondrial dysfunction with accumulation of mtDNA deletions. METHODS mtDNA copy number and deletions, and p53 gene copy ratios were evaluated in peripheral blood monocytic cells from children aged 2-5 years with AU (n = 66), race-, gender-, and age-matched typically neurodeveloping children (n = 46), and both parents from each diagnostic group, recruited by the Childhood Autism Risk from Genes and Environment study at the University of California, Davis. RESULTS mtDNA deletions and higher p53 gene copy ratios were more common in children with AU and their fathers. The incidence of mtDNA deletions in fathers of children with AU was increased 1.9-fold over fathers of typically neurodeveloping children, suggesting a role for deficient DNA repair capacity not driven by paternal age. Deletions in mtDNA and altered p53 gene copy ratios seem to result from genetics (children with severity scores ≥8) and/or act in concert with environmental factors (children with 6-7 severity scores). CONCLUSIONS Given pro- and antioxidant activities of p53, and associations of genomic instability with disorders other than AU, our study suggests a link between DNA repair capacity, genomic instability in the 17p13.1 region influenced by environmental triggers, and AU diagnosis.
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Affiliation(s)
- Sarah Wong
- Department of Molecular Biosciences, School of Veterinary Medicine
| | - Eleonora Napoli
- Department of Molecular Biosciences, School of Veterinary Medicine
| | | | - Flora Tassone
- Biochemistry and Molecular Medicine, School of Medicine, and,Medical Investigations of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Davis, California
| | - Irva Hertz-Picciotto
- Departments of Public Health Sciences and,Medical Investigations of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Davis, California
| | - Cecilia Giulivi
- Department of Molecular Biosciences, School of Veterinary Medicine, Medical Investigations of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Davis, California
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11
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Pallocca G, Grinberg M, Henry M, Frickey T, Hengstler JG, Waldmann T, Sachinidis A, Rahnenführer J, Leist M. Identification of transcriptome signatures and biomarkers specific for potential developmental toxicants inhibiting human neural crest cell migration. Arch Toxicol 2015; 90:159-80. [PMID: 26705709 PMCID: PMC4710658 DOI: 10.1007/s00204-015-1658-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 12/09/2015] [Indexed: 01/03/2023]
Abstract
The in vitro test battery of the European research consortium ESNATS (‘novel stem cell-based test systems’) has been used to screen for potential human developmental toxicants. As part of this effort, the migration of neural crest (MINC) assay has been used to evaluate chemical effects on neural crest function. It identified some drug-like compounds in addition to known environmental toxicants. The hits included the HSP90 inhibitor geldanamycin, the chemotherapeutic arsenic trioxide, the flame-retardant PBDE-99, the pesticide triadimefon and the histone deacetylase inhibitors valproic acid and trichostatin A. Transcriptome changes triggered by these substances in human neural crest cells were recorded and analysed here to answer three questions: (1) can toxicants be individually identified based on their transcript profile; (2) how can the toxicity pattern reflected by transcript changes be compacted/dimensionality-reduced for practical regulatory use; (3) how can a reduced set of biomarkers be selected for large-scale follow-up? Transcript profiling allowed clear separation of different toxicants and the identification of toxicant types in a blinded test study. We also developed a diagrammatic system to visualize and compare toxicity patterns of a group of chemicals by giving a quantitative overview of altered superordinate biological processes (e.g. activation of KEGG pathways or overrepresentation of gene ontology terms). The transcript data were mined for potential markers of toxicity, and 39 transcripts were selected to either indicate general developmental toxicity or distinguish compounds with different modes-of-action in read-across. In summary, we found inclusion of transcriptome data to largely increase the information from the MINC phenotypic test.
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Affiliation(s)
- Giorgia Pallocca
- Department of In Vitro Toxicology and Biomedicine, University of Konstanz, Box 657, 78457, Constance, Germany.
| | - Marianna Grinberg
- Department of Statistics, TU Dortmund University, 44139, Dortmund, Germany
| | - Margit Henry
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, University of Cologne, 50931, Cologne, Germany
| | - Tancred Frickey
- Department of Bioinformatics, University of Konstanz, 78457, Constance, Germany
| | - Jan G Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Technical University of Dortmund, 44139, Dortmund, Germany
| | - Tanja Waldmann
- Department of In Vitro Toxicology and Biomedicine, University of Konstanz, Box 657, 78457, Constance, Germany
| | - Agapios Sachinidis
- Department of Bioinformatics, University of Konstanz, 78457, Constance, Germany
| | - Jörg Rahnenführer
- Department of Statistics, TU Dortmund University, 44139, Dortmund, Germany
| | - Marcel Leist
- Department of In Vitro Toxicology and Biomedicine, University of Konstanz, Box 657, 78457, Constance, Germany
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12
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Wu H, Cao L, Li F, Lian P, Zhao J. Multiple biomarkers of the cytotoxicity induced by BDE-47 in human embryonic kidney cells. CHEMOSPHERE 2015; 126:32-39. [PMID: 25697951 DOI: 10.1016/j.chemosphere.2015.01.055] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 01/23/2015] [Accepted: 01/27/2015] [Indexed: 06/04/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are widely used as brominated flame-retardants in a variety of industrial products. Among these PBDEs, 2,2',4,4'-tetra-bromodiphenyl ether (BDE-47) is one of the most predominant congeners inducing multiple toxicities, including hepatotoxicity, neurotoxicity, cytotoxicity, genotoxicity, carcinogenecity and immunotoxicity in human body. In this study, the cytotoxicity of BDE-47 in human embryonic kidney cells (HEK293) was investigated by a set of bioassays, including cell proliferation, apoptosis, oxidative stress and metabolic responses as well as gene expressions related to apoptosis. Results showed that BDE-47 induced an inverted U-shaped curve of cell proliferation in HEK293 cells from 10(-6) to 10(-4) M. Cell apoptosis and ROS overproduction were detected at 10(-5) M of BDE-47 (p<0.05). In addition, the expressions of Bcl-2 family-encoding genes (Bad, Hrk and Bcl-2) increased significantly in 10(-4)M group (p<0.05). Metabolic responses indicated that BDE-47 mainly caused disturbance in energy metabolism marked by differentially altered ethanol, glutathione, creatine, aspartate, UDP-glucose and NAD(+). The increased lactate/alanine ratios indicated the higher reductive state induced by BDE-47 in all exposures confirmed by the overproduction of ROS.
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Affiliation(s)
- Huifeng Wu
- Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes, Yantai, Shandong 264003, PR China
| | - Lulu Cao
- Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes, Yantai, Shandong 264003, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Fei Li
- Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes, Yantai, Shandong 264003, PR China.
| | - Peiwen Lian
- Department of Center Laboratory, Yantai Yuhuangding Hospital, Yuhuangdingdong Road 20, Yantai 264000, PR China
| | - Jianmin Zhao
- Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Provincial Key Laboratory of Coastal Zone Environmental Processes, Yantai, Shandong 264003, PR China
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13
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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: 189] [Impact Index Per Article: 18.9] [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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14
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Tetz LM, Cheng AA, Korte CS, Giese RW, Wang P, Harris C, Meeker JD, Loch-Caruso R. Mono-2-ethylhexyl phthalate induces oxidative stress responses in human placental cells in vitro. Toxicol Appl Pharmacol 2013; 268:47-54. [PMID: 23360888 DOI: 10.1016/j.taap.2013.01.020] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 01/11/2013] [Accepted: 01/12/2013] [Indexed: 12/12/2022]
Abstract
Di-2-ethylhexyl phthalate (DEHP) is an environmental contaminant commonly used as a plasticizer in polyvinyl chloride products. Exposure to DEHP has been linked to adverse pregnancy outcomes in humans including preterm birth, low birth-weight, and pregnancy loss. Although oxidative stress is linked to the pathology of adverse pregnancy outcomes, effects of DEHP metabolites, including the active metabolite, mono-2-ethylhexyl phthalate (MEHP), on oxidative stress responses in placental cells have not been previously evaluated. The objective of the current study is to identify MEHP-stimulated oxidative stress responses in human placental cells. We treated a human placental cell line, HTR-8/SVneo, with MEHP and then measured reactive oxygen species (ROS) generation using the dichlorofluorescein assay, oxidized thymine with mass-spectrometry, redox-sensitive gene expression with qRT-PCR, and apoptosis using a luminescence assay for caspase 3/7 activity. Treatment of HTR-8 cells with 180μM MEHP increased ROS generation, oxidative DNA damage, and caspase 3/7 activity, and resulted in differential expression of redox-sensitive genes. Notably, 90 and 180μM MEHP significantly induced mRNA expression of prostaglandin-endoperoxide synthase 2 (PTGS2), an enzyme important for synthesis of prostaglandins implicated in initiation of labor. The results from the present study are the first to demonstrate that MEHP stimulates oxidative stress responses in placental cells. Furthermore, the MEHP concentrations used were within an order of magnitude of the highest concentrations measured previously in human umbilical cord or maternal serum. The findings from the current study warrant future mechanistic studies of oxidative stress, apoptosis, and prostaglandins as molecular mediators of DEHP/MEHP-associated adverse pregnancy outcomes.
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Affiliation(s)
- Lauren M Tetz
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI 48109-2029, USA.
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15
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Vagula MC, Kubeldis N, Nelatury CF. Effects of BDE-85 on the Oxidative Status and Nerve Conduction in Rodents. Int J Toxicol 2011; 30:428-34. [DOI: 10.1177/1091581811411109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BDE-85 is a congener of a class of flame-retardant compounds called polybrominated diphenyl ethers (PBDEs). Although there are some studies on other congeners of PBDEs, there are none on the toxicity potential of this penta-BDE member. This study, therefore, reports the oxidative status and sciatic nerve conduction properties following BDE-85 treatment in rodents. The oxidative stress markers, lipid hydroperoxides, and the activities of antioxidant enzymes, namely superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione-S-transferase (GST), and catalase, in the exposed mice liver and brain tissues showed tissue-specific alterations following intraperitoneal injection of 0.25 mg/kg body weight of BDE-85 for 4 days. The results indicate a significant disruption in the oxidant/antioxidant equilibrium and setting in of oxidative stress. Isolated sciatic nerves of rats exposed to 5 µg/mL or 20 µg/mL of BDE-85 showed a significant reduction in nerve conduction velocity and compound action potential amplitudes, indicating physiological damage to the sciatic nerves.
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16
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Is decabromodiphenyl ether (BDE-209) a developmental neurotoxicant? Neurotoxicology 2010; 32:9-24. [PMID: 21182867 DOI: 10.1016/j.neuro.2010.12.010] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Revised: 12/13/2010] [Accepted: 12/13/2010] [Indexed: 11/24/2022]
Abstract
Polybrominated diphenyl ether (PBDE) flame retardants have become ubiquitous environmental pollutants. The relatively higher body burden in toddlers and children has raised concern for their potential developmental neurotoxicity, which has been suggested by animal studies, in vitro experiments, and recent human epidemiological evidence. While lower brominated PBDEs have been banned in several countries, the fully brominated decaBDE (BDE-209) is still utilized, though manufacturers will discontinue production in the U.S.A. in 2013. The recent decision by the U.S. Environmental Protection Agency to base the reference dose (RfD) for BDE-209 on a developmental neurotoxicity study has generated some controversy. Because of its bulky configuration, BDE-209 is poorly absorbed and does not easily penetrate the cell wall. Its acute and chronic toxicities are relatively low, with the liver and the thyroid as the primary targets, though there is some evidence of carcinogenicity. A few animal studies have indicated that BDE-209 may cause developmental neurotoxicity, affecting motor and cognitive domains, as seen for other PBDEs. Limited in vivo and in vitro studies have also evidenced effects of BDE-209 on thyroid hormone homeostasis and direct effects on nervous cells, again similar to what found with other lower brominated PBDEs. In contrast, a recent developmental neurotoxicity study, carried out according to international guidelines, has provided no evidence of adverse effects on neurodevelopment, and this should be considered in a future re-evaluation of BDE-209. While estimated exposure to BDE-209 in children is believed to be several orders of magnitude below the most conservative RfD proposed by the USEPA, questions remain on the extent and relevance of BDE-209 metabolism to lower brominated PBDEs in the environment and in humans.
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