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Beausoleil C, Thébault A, Andersson P, Cabaton NJ, Ermler S, Fromenty B, Garoche C, Griffin JL, Hoffmann S, Kamstra JH, Kubickova B, Lenters V, Kos VM, Poupin N, Remy S, Sapounidou M, Zalko D, Legler J, Jacobs MN, Rousselle C. Weight of evidence evaluation of the metabolism disrupting effects of triphenyl phosphate using an expert knowledge elicitation approach. Toxicol Appl Pharmacol 2024:116995. [PMID: 38862081 DOI: 10.1016/j.taap.2024.116995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 06/05/2024] [Accepted: 06/07/2024] [Indexed: 06/13/2024]
Abstract
Identification of Endocrine-Disrupting Chemicals (EDCs) in a regulatory context requires a high level of evidence. However, lines of evidence (e.g. human, in vivo, in vitro or in silico) are heterogeneous and incomplete for quantifying evidence of the adverse effects and mechanisms involved. To date, for the regulatory appraisal of metabolism-disrupting chemicals (MDCs), no harmonised guidance to assess the weight of evidence has been developed at the EU or international level. To explore how to develop this, we applied a formal Expert Knowledge Elicitation (EKE) approach within the European GOLIATH project. EKE captures expert judgment in a quantitative manner and provides an estimate of uncertainty of the final opinion. As a proof of principle, we selected one suspected MDC -triphenyl phosphate (TPP) - based on its related adverse endpoints (obesity/adipogenicity) relevant to metabolic disruption and a putative Molecular Initiating Event (MIE): activation of peroxisome proliferator activated receptor gamma (PPARγ). We conducted a systematic literature review and assessed the quality of the lines of evidence with two independent groups of experts within GOLIATH, with the objective of categorising the metabolic disruption properties of TPP, by applying an EKE approach. Having followed the entire process separately, both groups arrived at the same conclusion, designating TPP as a "suspected MDC" with an overall quantitative agreement exceeding 85%, indicating robust reproducibility. The EKE method provides to be an important way to bring together scientists with diverse expertise and is recommended for future work in this area.
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Affiliation(s)
- Claire Beausoleil
- French Agency for Food, Environmental and Occupational Health and Safety (Anses), 94701 Maisons-Alfort, France.
| | - Anne Thébault
- French Agency for Food, Environmental and Occupational Health and Safety (Anses), 94701 Maisons-Alfort, France
| | | | - Nicolas J Cabaton
- INRAE. UMR1331 Toxalim (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, INP-Purpan, UT3, 31027 Toulouse, France
| | - Sibylle Ermler
- Department of Life Sciences, Centre of Genome Engineering and Maintenance, College of Health, Medicine and Life Sciences, Brunel University London, UB8 3PH Uxbridge, United Kingdom
| | - Bernard Fromenty
- INSERM, Univ Rennes, INRAE, Institut NUMECAN (Nutrition Metabolisms and Cancer) UMR_A 1341, UMR_S 1317, F-35000 Rennes, France
| | - Clémentine Garoche
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194, Université Montpellier, Institut Régional du Cancer de Montpellier (ICM), Montpellier, France
| | - Julian L Griffin
- The Rowett Institute, Foresterhill Health Campus, University of Aberdeen, Aberdeen, UK
| | | | - Jorke H Kamstra
- Institute for Risk Assessment Sciences, Department of Population Health Sciences, Utrecht University, Utrecht, the Netherlands
| | - Barbara Kubickova
- Radiation, Chemical and Environmental Hazards (RCE), Department of Toxicology, UK Health Security Agency (UKHSA), Harwell Science and Innovation Campus, Chilton OX11 0RQ, Oxon, United Kingdom
| | - Virissa Lenters
- Institute for Risk Assessment Sciences, Department of Population Health Sciences, Utrecht University, Utrecht, the Netherlands
| | - Vesna Munic Kos
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Nathalie Poupin
- INRAE. UMR1331 Toxalim (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, INP-Purpan, UT3, 31027 Toulouse, France
| | - Sylvie Remy
- Flemish Institute for Technological Research (VITO), 2400 Mol, Belgium
| | | | - Daniel Zalko
- INRAE. UMR1331 Toxalim (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, INP-Purpan, UT3, 31027 Toulouse, France
| | - Juliette Legler
- Institute for Risk Assessment Sciences, Department of Population Health Sciences, Utrecht University, Utrecht, the Netherlands
| | - Miriam N Jacobs
- Radiation, Chemical and Environmental Hazards (RCE), Department of Toxicology, UK Health Security Agency (UKHSA), Harwell Science and Innovation Campus, Chilton OX11 0RQ, Oxon, United Kingdom
| | - Christophe Rousselle
- French Agency for Food, Environmental and Occupational Health and Safety (Anses), 94701 Maisons-Alfort, France
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Yun K, Jeon H, Kho Y, Ji K. Potential adverse outcome pathway of neurodevelopmental toxicity, inflammatory response, and oxidative stress induction mediated by three alkyl organophosphate flame retardants in zebrafish larvae. CHEMOSPHERE 2024; 356:141901. [PMID: 38583538 DOI: 10.1016/j.chemosphere.2024.141901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Revised: 04/01/2024] [Accepted: 04/02/2024] [Indexed: 04/09/2024]
Abstract
Following restrictions on polybrominated flame retardants, trimethyl phosphate (TMP), triethyl phosphate (TEP), and tris(2-butoxyethyl) phosphate (TBEP) have been frequently used as plasticizers for fire-resistant plastics. This study investigated the neurodevelopmental effects, inflammatory response, and oxidative stress induction of three alkyl organophosphate flame retardants using a zebrafish embryo/larvae model. After exposure of zebrafish embryos to TMP, TEP, and TBEP (0, 0.02, 0.2, 2, 20, and 200 μg L-1) for 96 h, survival, development, swimming behavior, changes in acetylcholinesterase (AChE) activity, dopamine, tumor necrosis factor-alpha (TNF-α), interleukin (IL), reactive oxygen species (ROS), and antioxidant enzyme activities were observed. Concentrations of TMP, TEP, and TBEP were also measured in the whole body of exposed larvae. Our results showed that exposure to 200 μg L-1 TEP and ≥20 μg L-1 TBEP significantly reduced larval body length; however, TMP had no significant effects on developmental parameters up to 200 μg L-1. After 96 h of exposure to TBEP, total distance moved, mean velocity, AChE, and dopamine concentrations were significantly decreased. Exposure to TEP and TBEP decreased the expression of genes that regulate central nervous system development (e.g. gap43 and mbpa), whereas ROS, antioxidant enzymes, TNF-α, and IL-1β concentrations were significantly increased. Notably, pretreatment with an antioxidant N-acetylcysteine reduced neurotoxicity and oxidative stress caused by TEP and TBEP. The results of this study demonstrated that exposure to TEP and TBEP causes oxidative stress and has adverse effects on the neurobehavioral and immune system of zebrafish, leading to hypoactivity and ultimately impairing development.
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Affiliation(s)
- Kijeong Yun
- Department of Environmental Health, Graduate School at Yongin University, Yongin, 17092, Republic of Korea
| | - Hyeri Jeon
- Department of Health, Environment and Safety, Eulji University, Seongnam, Gyeonggi, 13135, Republic of Korea
| | - Younglim Kho
- Department of Health, Environment and Safety, Eulji University, Seongnam, Gyeonggi, 13135, Republic of Korea
| | - Kyunghee Ji
- Department of Environmental Health, Graduate School at Yongin University, Yongin, 17092, Republic of Korea.
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Cheng FJ, Tsai KF, Huang KC, Kung CT, Huang WT, You HL, Li SH, Wang CC, Lee WC, Pan HY. Association between organophosphate flame retardant exposure and lipid metabolism: data from the 2013-2014 National Health and Nutrition Examination Survey. Front Public Health 2024; 12:1340261. [PMID: 38525338 PMCID: PMC10959188 DOI: 10.3389/fpubh.2024.1340261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 02/06/2024] [Indexed: 03/26/2024] Open
Abstract
Organophosphate flame retardants (OPFRs) are emerging environmental pollutants that can be detected in water, dust, and biological organisms. Certain OPFRs can disrupt lipid metabolism in animal models and cell lines. However, the effects of OPFRs on human lipid metabolism remain unclear. We included 1,580 participants (≥20 years) from the 2013-2014 National Health and Nutrition Examination Survey (NHANES) to explore the relationship between OPFR exposure and lipid metabolism biomarkers. After adjusting for confounding factors, results showed that one-unit increases in the log levels of diphenyl phosphate (DPhP) (regression coefficient = -5.755; S.E. = 2.289; p = 0.023) and log bis-(1-chloro-2-propyl) phosphate (BCPP) (regression coefficient = -4.637; S.E. = 2.019; p = 0.036) were negatively associated with the levels of total cholesterol (TC) in all participants. One-unit increases in the levels of DPhP (regression coefficient = -2.292; S.E. = 0.802; p = 0.012), log bis (1,3-dichloro-2-propyl) phosphate (BDCPP) (regression coefficient = -2.046; S.E. = 0.825; p = 0.026), and log bis-2-chloroethyl phosphate (BCEP) (regression coefficient = -2.604; S.E. = 0.704; p = 0.002) were negatively associated with the levels of high-density lipoprotein cholesterol (HDL-C). With increasing quartiles of urine BDCPP levels, the mean TC levels significantly decreased in all participants (p value for trend = 0.028), and quartile increases in the levels of DPhP (p value for trend = 0.01), BDCPP (p value for trend = 0.001), and BCEP (p value for trend<0.001) were negatively corelated with HDL-C, with approximately 5.9, 9.9, and 12.5% differences between the upper and lower quartiles. In conclusion, DPhP, BDCPP, and BCEP were negatively related to HDL-C concentration, whereas DPhP and BCPP levels were negatively associated with TC level. Thus, exposure to OPFRs may interfere with lipid metabolism.
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Affiliation(s)
- Fu-Jen Cheng
- Department of Emergency Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Kai-Fan Tsai
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Kuo-Chen Huang
- Department of Emergency Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Chia-Te Kung
- Department of Emergency Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Wan-Ting Huang
- Department of Laboratory Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Huey-Ling You
- Department of Laboratory Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Shau-Hsuan Li
- Division of Hematology-Oncology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Chin-Chou Wang
- Department of Occupational Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Wen-Chin Lee
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Hsiu-Yung Pan
- Department of Emergency Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
- Department of Safety, Health and Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan
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Ai S, Chen X, Zhou Y. Critical review on organophosphate esters in water environment: Occurrence, health hazards and removal technologies. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 343:123218. [PMID: 38147949 DOI: 10.1016/j.envpol.2023.123218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/15/2023] [Accepted: 12/22/2023] [Indexed: 12/28/2023]
Abstract
Organophosphate esters (OPEs), which are phosphoric acid ester derivatives, are anthropogenic substances that are widely used in commerce. Nevertheless, there is growing public concern about these ubiquitous contaminants, which are frequently detected in contaminated water sources. OPEs are mostly emitted by industrial operations, and the primary routes of human exposure to OPEs include food intake and dermal absorption. Because of their negative effects on both human health and the environment, it is clear that innovative methods are needed to facilitate their eradication. In this study, we present a comprehensive overview of the existing characteristics and origins of OPEs, their possible impacts on human health, and the merits, drawbacks, and future possibilities of contemporary sophisticated remediation methods. Current advanced remediation approaches for OPEs include adsorption, degradation (advanced oxidation, advanced reduction, and redox technology), membrane filtration, and municipal wastewater treatment plants, degradation and adsorption are the most promising removal technologies. Meanwhile, we proposed potential areas for future research (appropriate management approaches, exploring the combination treatment process, economic factors, and potential for secondary pollution). Collectively, this work gives a comprehensive understanding of OPEs, providing useful insights for future research on OPEs pollution.
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Affiliation(s)
- Shali Ai
- Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Environment and Ecology, Hunan Agricultural University, Changsha, 410128, China
| | - Xia Chen
- Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Environment and Ecology, Hunan Agricultural University, Changsha, 410128, China
| | - Yaoyu Zhou
- Hunan International Scientific and Technological Cooperation Base of Agricultural Typical Pollution Remediation and Wetland Protection, College of Environment and Ecology, Hunan Agricultural University, Changsha, 410128, China.
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Zhou Y, Liao H, Yin S, Wang P, Ye X, Zhang J. Aryl-, halogenated- and alkyl- organophosphate esters induced oxidative stress, endoplasmic reticulum stress and NLRP3 inflammasome activation in HepG2 cells. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 316:120559. [PMID: 36328282 DOI: 10.1016/j.envpol.2022.120559] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 10/24/2022] [Accepted: 10/28/2022] [Indexed: 06/16/2023]
Abstract
Organophosphate esters (OPEs) are a group of extensively used man-made chemicals with diverse substituents that are ubiquitously detected in human-related samples including serum, breastmilk, food and house dust. The understanding of their toxicological effects and potential mechanisms on hepatocytes is still limited. In this study, nine most frequently detected OPEs were selected and divided into three subgroups (aryl-, halogenated- and alkyl-OPEs) based on their substituents. The cytotoxicity, apoptosis, oxidative stress, endoplasmic reticulum (ER) stress and NLRP3 inflammasome activation induced by OPEs were evaluated in human hepatocellular carcinomas HepG2 cells. All OPEs induced apoptosis likely through a caspase-dependent apoptotic pathway. The activities of anti-oxidative enzyme SOD and CAT exhibited sensitive responses after OPEs treatment for 6 h. The OPEs induced ROS overproduction, DNA damage, endoplasmic reticulum (ER) stress and NLRP3 inflammasome activation varied among aryl-, halogenated- and alkyl-OPEs. Halogenated- and alkyl- OPEs induced overproduction of ROS and DNA damage, and elevated ER stress and NLRP3 inflammasome activation are observed aryl-OPEs induced cytotoxicity.
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Affiliation(s)
- Yuanyuan Zhou
- Department of Nutrition and Toxicology, School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang, 311121, China
| | - Hanyu Liao
- Department of Nutrition and Toxicology, School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang, 311121, China
| | - Shanshan Yin
- Interdisciplinary Research Academy (IRA), Zhejiang Shuren University, Hangzhou, 310015, China
| | - Pengqiao Wang
- Department of Nutrition and Toxicology, School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang, 311121, China
| | - Xiaoqing Ye
- School of Medical Technology and Information Engineering, Zhejiang Chinese Medical University, Hangzhou 310053, China
| | - Jianyun Zhang
- Department of Nutrition and Toxicology, School of Public Health, Hangzhou Normal University, Hangzhou, Zhejiang, 311121, China.
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Pan HY, Cheng FJ, Huang KC, Kung CT, Huang WT, You HL, Li SH, Wang CC, Lee WC, Hsu PC. Exposure to tris(2-butoxyethyl) phosphate induces abnormal sperm morphology and testicular histopathology in male rats. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 241:113718. [PMID: 35660377 DOI: 10.1016/j.ecoenv.2022.113718] [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: 03/15/2022] [Revised: 05/25/2022] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
Tris(2-butoxyethyl) phosphate (TBEP) is one of the most abundant organophosphate flame retardants in the environment. This study aimed to evaluate the effect of TBEP exposure during adolescence on male reproductive function in adult rats. Male Sprague-Dawley rats were treated with 20 and 200 mg/kg body weight of TBEP or corn oil from postnatal day (PND) 42 to PND 105. A significant increase in the proportion of sperm with abnormal morphology (flattened head and bent tail) and superoxide anion (O2-.) production in the sperm of the 200 mg/kg treated group was observed (p < 0.05). Excessive production of sperm hydrogen peroxide (H2O2) was found in both the 20 and 200 mg/kg treatment groups (p < 0.05). Disruption of testicular structure was observed in the 20 and 200 mg/kg treated groups and seminiferous tubule degeneration was observed in the 200 mg/kg treated group. Our study demonstrated the adverse effects of TBEP on male reproductive function in rats.
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Affiliation(s)
- Hsiu-Yung Pan
- Department of Emergency Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung County, Taiwan; Department of Safety, Health and Environmental Engineering, National Kaohsiung University of Science and Technology, Taiwan
| | - Fu-Jen Cheng
- Department of Emergency Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung County, Taiwan
| | - Kuo-Chen Huang
- Department of Emergency Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung County, Taiwan
| | - Chia-Te Kung
- Department of Emergency Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung County, Taiwan
| | - Wan-Ting Huang
- Department of Laboratory Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Huey-Ling You
- Department of Laboratory Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Shau-Hsuan Li
- Division of Hematology-Oncology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Chin-Chou Wang
- Department of Occupational Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Wen-Chin Lee
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Ping-Chi Hsu
- Department of Safety, Health and Environmental Engineering, National Kaohsiung University of Science and Technology, Taiwan.
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Delbes G, Blázquez M, Fernandino JI, Grigorova P, Hales BF, Metcalfe C, Navarro-Martín L, Parent L, Robaire B, Rwigemera A, Van Der Kraak G, Wade M, Marlatt V. Effects of endocrine disrupting chemicals on gonad development: Mechanistic insights from fish and mammals. ENVIRONMENTAL RESEARCH 2022; 204:112040. [PMID: 34509487 DOI: 10.1016/j.envres.2021.112040] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 09/03/2021] [Accepted: 09/08/2021] [Indexed: 06/13/2023]
Abstract
Over the past century, evidence has emerged that endocrine disrupting chemicals (EDCs) have an impact on reproductive health. An increased frequency of reproductive disorders has been observed worldwide in both wildlife and humans that is correlated with accidental exposures to EDCs and their increased production. Epidemiological and experimental studies have highlighted the consequences of early exposures and the existence of key windows of sensitivity during development. Such early in life exposures can have an immediate impact on gonadal and reproductive tract development, as well as on long-term reproductive health in both males and females. Traditionally, EDCs were thought to exert their effects by modifying the endocrine pathways controlling reproduction. Advances in knowledge of the mechanisms regulating sex determination, differentiation and gonadal development in fish and rodents have led to a better understanding of the molecular mechanisms underlying the effects of early exposure to EDCs on reproduction. In this manuscript, we review the key developmental stages sensitive to EDCs and the state of knowledge on the mechanisms by which model EDCs affect these processes, based on the roadmap of gonad development specific to fish and mammals.
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Affiliation(s)
- G Delbes
- Centre Armand Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Canada.
| | - M Blázquez
- Institute of Marine Sciences (ICM-CSIC), Barcelona, Spain
| | - J I Fernandino
- Instituto Tecnológico de Chascomús (CONICET-UNSAM), Chascomús, Argentina
| | | | - B F Hales
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Canada
| | - C Metcalfe
- School of Environment, Trent University, Trent, Canada
| | - L Navarro-Martín
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Barcelona, Spain
| | - L Parent
- Université TELUQ, Montréal, Canada
| | - B Robaire
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Canada; Department of Obstetrics and Gynecology, McGill University, Montreal, Canada
| | - A Rwigemera
- Centre Armand Frappier Santé Biotechnologie, Institut National de la Recherche Scientifique (INRS), Laval, Canada
| | - G Van Der Kraak
- Department of Integrative Biology, University of Guelph, Guelph, Canada
| | - M Wade
- Environmental Health Science & Research Bureau, Health Canada, Ottawa, Canada
| | - V Marlatt
- Department of Biological Sciences, Simon Fraser University, Burnaby, Canada
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Yanagisawa R, Koike E, Win-Shwe TT, Kawaguchi M, Takano H. The impact of oral exposure to low-dose tris(2-butoxyethyl) phosphate in allergic asthmatic mice. J Appl Toxicol 2020; 40:1498-1510. [PMID: 32497324 DOI: 10.1002/jat.4001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/29/2020] [Accepted: 04/29/2020] [Indexed: 12/24/2022]
Abstract
Tris(2-butoxyethyl) phosphate (TBEP) is a major organophosphorus flame retardant and has been widely increasing as a substitute for brominated flame retardants. TBEP may have adverse effects on human health; however, its impact on immune and allergic responses remains largely uncharacterized. In this study, the effects of low-dose TBEP comparable with the level of actual human exposure to that of human tolerable daily intake on allergic asthmatic mice were explored. Five-week-old C3H/HeJSlc male mice consumed a diet containing approximately 0.02, 0.2 or 2 μg/kg/day TBEP and were intratracheally administrated ovalbumin (OVA) (1 μg/mouse every 2 weeks from 5 to 11 weeks of age). Exposure to 2 μg/kg/day TBEP with OVA tended to enhance allergic pulmonary inflammation and significantly elevated mRNA levels of interleukin-5, eotaxin-1 and estrogen receptor alpha (ERα) compared with OVA alone. In mediastinal lymph nodes (MLNs), TBEP (0.2 or 2 μg/kg/day) with OVA significantly increased in total cell number and promoted conventional dendritic cell activation than OVA alone; MLN cell proliferation by OVA restimulation was also enhanced in these groups. In the bone marrow (BM), TBEP (0.02 or 0.2 μg/kg/day) with OVA resulted in a net decrease in total cell number and fraction of CCR2+ Gr-1+ cells; the fraction of Gr-1+ cells increased. In conclusion, oral exposure to low-dose TBEP levels equivalent to tolerable daily intake may exacerbate allergic pulmonary inflammation by promoting a skewed T-helper 2 cell response, upregulation of ERα and dysregulation of both MLN and BM microenvironments.
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Affiliation(s)
- Rie Yanagisawa
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, Japan
| | - Eiko Koike
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, Japan
| | - Tin-Tin Win-Shwe
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, Japan
| | | | - Hirohisa Takano
- Graduate School of Global Environmental Studies, Kyoto, Japan
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Kuiper JR, Stapleton HM, Wills-Karp M, Wang X, Burd I, Buckley JP. Predictors and reproducibility of urinary organophosphate ester metabolite concentrations during pregnancy and associations with birth outcomes in an urban population. Environ Health 2020; 19:55. [PMID: 32448197 PMCID: PMC7247187 DOI: 10.1186/s12940-020-00610-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/15/2020] [Indexed: 05/14/2023]
Abstract
BACKGROUND Organophosphate esters (OPEs) are synthetic chemicals used as flame retardants and plasticizers in a variety of goods. Despite ubiquitous human exposures and laboratory evidence that prenatal OPE exposures may disrupt offspring metabolism, perinatal studies of OPE health effects are limited. The objectives of this study were to: 1) Determine predictors and reproducibility of urinary OPE biomarker concentrations during pregnancy, and 2) Estimate the relation of prenatal OPE exposures with birth outcomes and cord blood adipokine and insulin concentrations. METHODS We analyzed five OPE metabolites in urine samples collected at up to three visits during pregnancy from 90 women enrolled in the ORigins of Child Health And Resilience in Development (ORCHARD) pregnancy cohort in Baltimore, MD from 2017 to 2019. To quantify the variability of metabolite concentrations during pregnancy, we calculated intraclass correlation coefficients (ICCs) for each metabolite using mixed effects regression models. Using self-reported questionnaire data collected during gestation, we assessed possible sociodemographic and environmental/behavioral predictors of each OPE metabolite using generalized estimating equations to account for repeated exposure measures. We ascertained birth outcomes of 76 offspring from medical records, including weight-for-gestational age, length, ponderal index, and gestational age. In a subset of 37 infants, we measured cord blood concentrations of leptin, adiponectin, and insulin. To account for repeated exposure measures, we used linear structural equation models to assess the relations of standard deviation (SD) increases in prenatal OPE metabolite factor scores with continuous birth outcomes and cord blood biomarker concentrations. RESULTS ICCs ranged from 0.09 for isopropylphenyl-phenyl phosphate (ip-PPP) to 0.59 for bis(1,3-dichloro-2-propyl) phosphate (BDCIPP). We observed little consistency in environmental or behavioral predictors of OPE exposures, although concentrations were generally lower for samples collected in the afternoon compared to morning and winter compared to other seasons. In adjusted analyses, a SD increase in BDCIPP concentration was associated with a 0.06 g/cm3 (95% CI: 0.00, 0.12) greater ponderal index. A SD increase in BDCIPP was associated with a 0.37 (95% CI: - 0.62, - 0.13) SD lower insulin concentration and 0.24 (95% CI: - 0.39, - 0.08) SD lower leptin concentration. Other OPEs were not associated with infant outcomes. CONCLUSIONS These findings suggest some OPEs may be metabolic disruptors warranting investigation in larger studies.
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Affiliation(s)
- Jordan R. Kuiper
- Department of Environmental Health and Engineering, Johns Hopkins University Bloomberg School of Public Health, 615 N. Wolfe Street, Room W7513A, Baltimore, MD 21205 USA
| | | | - Marsha Wills-Karp
- Department of Environmental Health and Engineering, Johns Hopkins University Bloomberg School of Public Health, 615 N. Wolfe Street, Room W7513A, Baltimore, MD 21205 USA
| | - Xiaobin Wang
- Department of Population, Family, and Reproductive Health, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD USA
| | - Irina Burd
- Integrated Research Center for Fetal Medicine, Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Jessie P. Buckley
- Department of Environmental Health and Engineering, Johns Hopkins University Bloomberg School of Public Health, 615 N. Wolfe Street, Room W7513A, Baltimore, MD 21205 USA
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10
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Yuan S, Han Y, Ma M, Rao K, Wang Z, Yang R, Liu Y, Zhou X. Aryl-phosphorus-containing flame retardants induce oxidative stress, the p53-dependent DNA damage response and mitochondrial impairment in A549 cells. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 250:58-67. [PMID: 30981936 DOI: 10.1016/j.envpol.2019.03.109] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/26/2019] [Accepted: 03/26/2019] [Indexed: 06/09/2023]
Abstract
Aryl phosphorus-containing flame retardants (aryl-PFRs) have been frequently detected with increasingly used worldwide as one of alternatives for brominated flame retardants. However, information on their adverse effects on human health and ecosystem is insufficient, with limited study on their molecular mode of action in vitro. In this study, the cytotoxicity, DNA damage, mitochondrial impairment and the involved molecular mechanisms of certain frequently detectable aryl-PFRs, including 2-ethylhexyldiphenyl phosphate (EHDPP), methyl diphenyl phosphate (MDPP), bisphenol-A bis (diphenyl phosphate) (BDP), isodecyl diphenyl phosphate (IDPP), cresyl diphenyl phosphate (CDP) and the structurally similar and widely used organophosphorus pesticide chlorpyrifos (CPF), were evaluated in A549 cells using high-content screening (HCS) system. Aryl-PFRs showed different lethal concentration 50 (LC50) values ranging from 97.94 to 546.85 μM in A549 cells using CCK-8 assay. EHDPP, IDPP, CDP, MDPP and CPF demonstrated an ability to induce DNA damage, evidenced by increased DNA content and S phase-reducing cell cycle arrest effect using fluorophore dye cocktail assay. Additionally, the selected aryl-PFRs induced mitochondrial impairment by the increasing mitochondrial mass and decreasing mitochondrial membrane potential. Moreover, BDP, MDPP, and CDP, which contain short alkyl chains showed their potential oxidative stress with intracellular ROS and mitochondrial superoxide overproduction from an initially relatively low concentration. Additionally, based on the promotion of firefly luminescence in p53-transfected A549 cells, p53 activation was found to be involved in aryl-PFRs-induced DNA damage. Further real-time PCR results showed that all selected aryl-PFRs triggered p53/p21/gadd45β-, and p53/p21/mdm2-mediated cell cycle pathways, and the p53/bax mediated apoptosis pathway to induce DNA damage and cytotoxic effects. These results suggest that aryl-PFRs (e.g., BDP, MDPP, CDP) cause oxidative stress-mediated DNA damage and mitochondrial impairment, and p53-dependent pathway was involved in the aryl-PFRs-induced DNA damage and cell cycle arrest. In conclusion, this study improves the understanding of PFRs-induced adverse outcomes and the involved molecular mechanism.
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Affiliation(s)
- Shengwu Yuan
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yingnan Han
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Mei Ma
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Kaifeng Rao
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Zijian Wang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Rong Yang
- Beijing Water Quality Monitoring Center for South-to-North Water Diversion, Beijing, 100093, China
| | - Yihong Liu
- Beijing Water Quality Monitoring Center for South-to-North Water Diversion, Beijing, 100093, China
| | - Xiaohong Zhou
- Center for Sensor Technology of Environment and Health, State Key Joint Laboratory of ESPC, School of Environment, Tsinghua University, Beijing, 100084, China
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11
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Hou R, Yuan S, Feng C, Xu Y, Rao K, Wang Z. Toxicokinetic patterns, metabolites formation and distribution in various tissues of the Chinese rare minnow (Gobiocypris rarus) exposed to tri(2‑butoxyethyl) phosphate (TBOEP) and tri-n-butyl phosphate (TNBP). THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 668:806-814. [PMID: 30870749 DOI: 10.1016/j.scitotenv.2019.03.038] [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: 12/14/2018] [Revised: 02/02/2019] [Accepted: 03/03/2019] [Indexed: 06/09/2023]
Abstract
Alkylated organophosphate esters (alkyl-OPEs) are widely used and extensively detected in aquatic organisms. This work investigated the tissue-specific toxicokinetics of two common alkyl-OPEs, tri(2‑butoxyethyl) phosphate (TBOEP) and tri‑n‑butyl phosphate (TNBP) in Chinese rare minnow (Gobiocypris rarus) through a 50 day uptake and depuration experiment. The tissue-specific bioconcentration factor (BCF) values for the two alkyl-OPEs ranged from 1 to 30 L/kg wet weight (ww), with the kidney and ovary as the tissues with the highest accumulation. The tissue BCFs only exhibited a significant correlation with lipid contents only in storage tissues (i.e., muscle, brain, ovary and testis), indicating that lipids might not be the major contributor to tissue distribution of TBOEP and TNBP. However, the contribution of blood perfusion and active transport to tissue-specific OPE accumulation needs to be further investigated. Lower accumulation of metabolites than parent chemicals was observed, with metabolite parent concentration factors (MPCFs) <1. Di-alkyl phosphate (DAP), bis(2‑butoxyethyl) phosphate (BBOEP) and di(n-butyl) phosphate (DNBP) were the most abundantly formed metabolites of TBOEP and TNBP in various tissues, followed by the monohydroxylated OPEs (OH-OPEs). However, bis(2‑butoxyethyl) hydroxyethyl phosphate (BBOEHEP), was detected at much lower levels in the tissues. All the investigated metabolites showed high production rates (kprod,metabolites) in the fish liver, followed by the GI tract and the kidney, indicating the importance of the hepatobiliary and urinary systems in eliminating the metabolites. Our study suggested that metabolism plays an important role in eliminating these two alkyl-OPEs in rare minnow and results in different tissue distribution mechanisms for metabolites and their compounds.
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Affiliation(s)
- Rui Hou
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Shengwu Yuan
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Chenglian Feng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yiping Xu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Kaifeng Rao
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Zijian Wang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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12
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Boyle M, Buckley JP, Quirós-Alcalá L. Associations between urinary organophosphate ester metabolites and measures of adiposity among U.S. children and adults: NHANES 2013-2014. ENVIRONMENT INTERNATIONAL 2019; 127:754-763. [PMID: 31003058 PMCID: PMC6685532 DOI: 10.1016/j.envint.2019.03.055] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 02/25/2019] [Accepted: 03/24/2019] [Indexed: 05/11/2023]
Abstract
BACKGROUND Organophosphate esters (OPEs) are synthetic chemicals found in many consumer products, including furniture, electronics, processed foods, and building materials. Emerging in vitro and in vivo studies suggest that OPEs are metabolism disrupting compounds; however, epidemiologic studies investigating their associations with adiposity markers are sparse. OBJECTIVE We examined cross-sectional associations between OPE biomarkers and adiposity measures among U.S. children and adults participating in the National Health and Nutrition Examination Survey (NHANES: 2013-2014). METHODS Concentrations of five OPE metabolites were quantified in urine: diphenyl phosphate (DPHP), bis(1,3-dichloro-2-propyl) phosphate (BDCPP), bis(2-chloroethyl) phosphate (BCEP), dibutyl phosphate (DBUP), and bis(1-chloro-2-propyl) phosphate (BCPP). We conducted covariate-adjusted logistic and linear regressions to examine associations between log2-transformed and dichotomized OPE metabolite concentrations and obesity, body mass index (BMI), and waist circumference (WC), separately among 784 children (6-19 years) and 1672 adults (≥20 years). We also assessed heterogeneity of associations by sex. RESULTS DBUP concentrations were inversely associated with the prevalence odds of being obese vs. normal weight in children (adjusted Prevalence Odds Ratio, aPOR: 0.82, 95% Confidence Interval, 95% CI: 0.70, 0.95) and adults (aPOR: 0.83, 95% CI: 0.72, 0.96). DBUP was also significantly associated with lower BMI z-scores (β:-0.08, 95% CI:-0.17, 0.01) and WC (β:-0.71, 95% CI: -1.49, 0.07) in children. BCEP concentrations were associated with increased prevalence odds of being overweight vs. normal weight (aPOR: 1.15, 95% CI: 1.01, 1.32) among children; similar, albeit not statistically significant, relationships were observed with other child adiposity outcomes. Among adults, detectable BCPP concentrations were associated with increased prevalence odds of being obese vs. normal weight (aPOR: 1.70, 95% CI: 1.21, 2.38) and having a high vs. normal WC (aPOR: 1.51, 95% CI: 1.11, 2.07) as well as higher BMI (β: 1.31, 95% CI: 0.30, 2.33). Other OPE metabolites were not consistently associated with adiposity measures among adults. Although associations of BCPP exposure with adiposity outcomes were generally inverse among boys, but not girls, we did not observe consistent evidence of sexually-dimorphic associations for other OPE metabolites. CONCLUSIONS Exposure to select OPEs may be differentially associated with body size among children and adults. Given the cross-sectional design of the present study, future prospective studies are needed to confirm these findings.
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Affiliation(s)
- M Boyle
- Maryland Institute of Applied Environmental Health, School of Public Health, University of Maryland, College Park, MD, USA
| | - J P Buckley
- Johns Hopkins University, Department of Environmental Health & Engineering, Department of Epidemiology, Baltimore, MD, USA
| | - L Quirós-Alcalá
- Maryland Institute of Applied Environmental Health, School of Public Health, University of Maryland, College Park, MD, USA.
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13
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Liu Q, Tang X, Wang Y, Yang Y, Zhang W, Zhao Y, Zhang X. ROS changes are responsible for tributyl phosphate (TBP)-induced toxicity in the alga Phaeodactylum tricornutum. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2019; 208:168-178. [PMID: 30677712 DOI: 10.1016/j.aquatox.2019.01.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/14/2019] [Accepted: 01/14/2019] [Indexed: 06/09/2023]
Abstract
As a newly emerging environmental contaminant, tributyl phosphate (TBP) is an additive flame retardant of high production volume that is frequently detected in biota and the environment. Despite evidence that TBP is a potential threat to marine organisms, ecotoxicology data for TBP in marine organisms at low trophic levels are scarce. In this study, the acute toxicological effect of TBP on the marine phytoplankton Phaeodactylum tricornutum was thoroughly investigated, and the possible mechanism was explored. The results showed that TBP at concentrations ≥0.2 mg L-1 significantly inhibited P. tricornutum growth in a clear dose-response manner, with 72-h EC10, EC20, EC50 and EC90 values of 0.067, 0.101, 0.219 and 0.716 mg L-1, respectively. Algal cells treated with TBP exhibited distorted shapes, ruptured cell membranes and damaged organelles, especially mitochondria. Additionally, apoptosis was triggered, followed by a decrease in mitochondrial membrane potential, indicating that cellular damage occurred during exposure. Although the activities of two antioxidant enzymes, superoxide peroxidase and catalase, were upregulated by TBP at 1.2 mg L-1, excess reactive oxygen species (ROS) and malondialdehyde still accumulated in algal cells after exposure, suggesting that the cells experienced oxidative stress. Moreover, both growth inhibition and apoptosis were positively correlated with ROS levels and were ameliorated by pretreatment with the ROS scavenger N-acetyl-l-cysteine. Taken together, the results indicate that TBP exposure leads to growth inhibition and cellular damage in P. tricornutum, and a ROS-mediated pathway might contribute to these observed toxicological effects.
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Affiliation(s)
- Qian Liu
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao, 266003, 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.
| | - Yingying Yang
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao, 266003, China.
| | - Wei Zhang
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao, 266003, China.
| | - Yunchen Zhao
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, Fujian, China.
| | - Xinxin Zhang
- 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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14
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Hou R, Huang C, Rao K, Xu Y, Wang Z. Characterized in Vitro Metabolism Kinetics of Alkyl Organophosphate Esters in Fish Liver and Intestinal Microsomes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:3202-3210. [PMID: 29439571 DOI: 10.1021/acs.est.7b05825] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Tris(2-butoxyethyl) phosphate (TBOEP) and tris( n-butyl) phosphate (TNBP) are the most commonly used alkyl organophosphate esters (alkyl-OPEs), and they increasingly accumulate in organisms and create potential health hazards. This study examined the metabolism of TNBP and TBOEP in Carassius carassius liver and intestinal microsomes and the production of their corresponding monohydroxylated and dealkylated metabolites. After 140 min of incubation with fish liver microsomes, the rapid depletion of TNBP and TBOEP were both best fitted to the Michaelis-Menten model (at administrated concentrations ranging from 0.5 to 200 μM), with a CLint (intrinsic clearance) of 3.1 and 3.9 μL·min-1·mg-1 protein, respectively. But no significant ( P > 0.05) biotransformation was observed for these compounds in intestinal microsomes at any administrated concentrations. In fish liver microsomes assay, bis(2-butoxyethyl) hydroxyethyl phosphate (BBOEHEP) and bis(2-butoxyethyl) 3-hydroxyl-2-butoxyethyl phosphate (3-OH-TBOEP) were the most abundant metabolites of TBOEP, and dibutyl-3-hydroxybutyl phosphate (3-OH-TNBP) was the predominant metabolite of TNBP. Similarly, the apparent Vmax values (maximum metabolic rate) of BBOEHEP and 3-OH-TNBP were also respectively highest among those of other metabolites. Further inhibition studies were conducted to identify the specific cytochrome P450 (CYP450) isozymes involved in the metabolism of TNBP and TBOEP in liver microsomes. It was confirmed that CYP3A4 and CYP1A were the significant CYP450 isoforms catalyzing the metabolism of TNBP and TBOEP in fish liver microsomes. Overall, this study emphasized the importance of hydroxylated metabolites as biomarkers for alkyl-OPEs exposure, and further research is needed to validate the in vivo formation and toxicological implications of these metabolites.
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Affiliation(s)
- Rui Hou
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
- University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Chao Huang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
- University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Kaifeng Rao
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
| | - Yiping Xu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
| | - Zijian Wang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences , Chinese Academy of Sciences , Beijing 100085 , China
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15
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Engeli RT, Fürstenberger C, Kratschmar DV, Odermatt A. Currently available murine Leydig cell lines can be applied to study early steps of steroidogenesis but not testosterone synthesis. Heliyon 2018; 4:e00527. [PMID: 29560447 PMCID: PMC5857625 DOI: 10.1016/j.heliyon.2018.e00527] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 12/12/2017] [Accepted: 01/23/2018] [Indexed: 02/08/2023] Open
Abstract
Androgen biosynthesis in males occurs to a large extent in testicular Leydig cells. This study focused on the evaluation of three murine Leydig cell lines as potential screening tool to test xenobiotics interfering with gonadal androgen synthesis. The final step of testosterone (T) production in Leydig cells is catalyzed by the enzyme 17β-hydroxysteroid dehydrogenase 3 (17β-hsd3). The endogenous 17β-hsd3 mRNA expression and Δ4-androstene-3,17-dione (AD) to T conversion were determined in the murine cell lines MA-10, BLTK1 and TM3. Additionally, effects of 8-Br-cAMP and forskolin stimulation on steroidogenesis and T production were analyzed. Steroids were quantified in supernatants of cells using liquid chromatography–tandem mass spectrometry. Unstimulated cells incubated with AD produced only very low T but substantial amounts of the inactive androsterone. Stimulated cells produced low amounts of T, moderate amounts of AD, but high amounts of progesterone. Gene expression analyses revealed barely detectable 17β-hsd3 levels, absence of 17β-hsd5 (Akr1c6), but substantial 17β-hsd1 expression in all three cell lines. Thus, MA-10, BLTK1 and TM3 cells are not suitable to study the expression and activity of the gonadal T synthesizing enzyme 17β-hsd3. The low T production reported in stimulated MA-10 cells are likely a result of the expression of 17β-hsd1. This study substantiates that the investigated Leydig cell lines MA-10, BLTK1, and TM3 are not suitable to study gonadal androgen biosynthesis due to altered steroidogenic pathways. Furthermore, this study emphasizes the necessity of mass spectrometry-based steroid quantification in experiments using steroidogenic cells such as Leydig cells.
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Affiliation(s)
- Roger T Engeli
- Swiss Centre for Applied Human Toxicology and Division of Molecular and Systems Toxicology, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland
| | - Cornelia Fürstenberger
- Swiss Centre for Applied Human Toxicology and Division of Molecular and Systems Toxicology, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland
| | - Denise V Kratschmar
- Swiss Centre for Applied Human Toxicology and Division of Molecular and Systems Toxicology, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland
| | - Alex Odermatt
- Swiss Centre for Applied Human Toxicology and Division of Molecular and Systems Toxicology, University of Basel, Klingelbergstrasse 50, 4056 Basel, Switzerland
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16
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Chen H, Wang P, Du Z, Wang G, Gao S. Oxidative stress, cell cycle arrest, DNA damage and apoptosis in adult zebrafish (Danio rerio) induced by tris(1,3-dichloro-2-propyl) phosphate. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2018; 194:37-45. [PMID: 29149642 DOI: 10.1016/j.aquatox.2017.11.001] [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: 07/18/2017] [Revised: 10/31/2017] [Accepted: 11/01/2017] [Indexed: 06/07/2023]
Abstract
Tris(1,3-dichloro-2-propyl)phosphate (TDCPP) is an additive flame retardant of high production volume, and frequently detected in biota and environment. However, knowledge on its potential risk and toxicological mechanism still remains limited. In this study, DNA damage, transcriptomic responses and biochemical changes in the liver of zebrafish (Danio rerio) induced by TDCPP were investigated. Zebrafish was exposed to 45.81μg/L (1/100 (96h-LC50)) and 229.05μg/L (1/20 (96h-LC50)) TDCPP for 7 d. The reactive oxygen species (ROS) and GSH contents, in addition to antioxidant enzyme activities in the liver changed significantly, and the mRNA levels of genes related to oxidative stress were alerted in a dose-dependent and/or sex-dependent manner after exposure to TDCPP. Significant DNA damage in zebrafish liver was found, and olive tail moment increased in a concentration-dependent manner. Moreover, exposure of TDCPP at 45.81μg/L level activated the cell cycle arrest, DNA repair system and apoptosis pathway in male zebrafish, and 229.05μg/L TDCPP exposure inhibited those pathways in both male and female zebrafish. The cell apoptosis was confirmed in TUNEL assay as higher incidence of TUNEL-positive cells were observed in zebrafish exposed to 229.05μg/L TDCPP. Our results also indicated that males were more sensitive to TDCPP exposure compared with females. Taken together, our results showed that TDCPP could induce oxidative stress, cell cycle arrest, DNA damage and apoptosis in adult zebrafish liver in sex- and concentration-dependent manners.
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Affiliation(s)
- Hanyan Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China
| | - Pingping Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China
| | - Zhongkun Du
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China
| | - Guowei Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China
| | - Shixiang Gao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China.
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17
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Wang X, He B, Kong B, Wei L, Wang R, Zhou C, Shao Y, Lin J, Jin Y, Fu Z. β-Cypermethrin and its metabolite 3-phenoxybenzoic acid exhibit immunotoxicity in murine macrophages. Acta Biochim Biophys Sin (Shanghai) 2017; 49:1083-1091. [PMID: 29040392 DOI: 10.1093/abbs/gmx111] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 09/24/2017] [Indexed: 12/13/2022] Open
Abstract
β-Cypermethrin (β-CYP), one of most important pyrethroids, is widely used to control insects, and has been detected in organisms, including human. Pyrethroids have been shown to pose neurotoxicity, hepatotoxicity, endocrine disruption and reproductive risks in mammals. However, research in immunotoxicity of pyrethroids, especially their metabolites, is limited. A common metabolite of pyrethroids is 3-phenoxybenzoic acid (3-PBA) in mammals. Thus, in this study, we evaluated the immunotoxicity of β-CYP and 3-PBA in mouse macrophages, RAW 264.7 cells. MTT assays showed that both β-CYP and 3-PBA reduced cell viability in a concentration- and time-dependent manner. Flow cytometry with Annexin-V/PI staining demonstrated that both β-CYP and 3-PBA induced RAW 264.7 cell apoptosis. Furthermore, our results also showed that N-acetylcysteine partially blocked β-CYP- and 3-PBA-induced cytotoxicity and apoptosis. Intrinsic apoptotic pathway was stimulated by both β-CYP and 3-PBA exposure. In addition, we found that β-CYP and 3-PBA inhibited mRNA levels of pro-inflammatory cytokines with or without LPS stimulation. Phagocytosis assay showed that both β-CYP and 3-PBA inhibited phagocytic ability of macrophages. Moreover, it was also found that both β-CYP and 3-PBA increased reactive oxygen species (ROS) levels in RAW 264.7 cells. Accordingly, both β-CYP and 3-PBA were found to regulate the mRNA levels of oxidative stress-related genes in RAW 264.7 cells. Taken together, the results obtained in this study demonstrated that β-CYP and 3-PBA may have immunotoxic effect on macrophages and that elevated ROS may underlie the mechanism. The present study will help to understand the health risks caused by β-CYP and other pyrethroids.
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Affiliation(s)
- Xia Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Bingnan He
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Baida Kong
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Lai Wei
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Rong Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Chenqian Zhou
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Yiyan Shao
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Jiajia Lin
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Yuanxiang Jin
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
| | - Zhengwei Fu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China
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18
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Huang C, Li N, Yuan S, Ji X, Ma M, Rao K, Wang Z. Aryl- and alkyl-phosphorus-containing flame retardants induced mitochondrial impairment and cell death in Chinese hamster ovary (CHO-k1) cells. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 230:775-786. [PMID: 28732339 DOI: 10.1016/j.envpol.2017.07.024] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Revised: 06/15/2017] [Accepted: 07/07/2017] [Indexed: 06/07/2023]
Abstract
Phosphorus-containing flame retardants (PFRs) are increasingly in demand worldwide as replacements for brominated flame retardants (BFRs), but insufficient available toxicological information on PFRs makes assessing their health risks challenging. Mitochondria are important targets of various environmental pollutants, and mitochondrial dysfunction may lead to many common diseases. In the present study, mitochondria impairment-related endpoints were measured by a high content screening (HCS) assay for 11 selected non-halogen PFRs in Chinese hamster ovary (CHO-k1) cells. A cluster analysis was used to categorize these PFRs into three groups according to their structural characteristics and results from the HCS assay. Two groups, containing long-chain alkyl-PFRs and all aryl-PFRs, were found to cause mitochondrial impairment but showed different mechanisms of toxicity. Due to the high correlation between cell death and mitochondrial impairment, two PFRs with different structures, trihexyl phosphate (THP) and cresyl diphenyl phosphate (CDP), were selected and compared with chlorpyrifos (CPF) to elucidate their mechanism of inducing cell death. THP (an alkyl-PFR) was found to utilize a similar pathway as CPF to induce apoptosis. However, cell death induced by CDP (an aryl-PFR) was different from classical necrosis based on experiments to discriminate among the different modes of cell death. These results confirm that mitochondria might be important targets for some PFRs and that differently structured PFRs could function via distinct mechanisms of toxicity.
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Affiliation(s)
- Chao Huang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 100085 Beijing, China; College of Resources and Environment, University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Na Li
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 100085 Beijing, China
| | - Shengwu Yuan
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 100085 Beijing, China; College of Resources and Environment, University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Xiaoya Ji
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 100085 Beijing, China; College of Resources and Environment, University of Chinese Academy of Sciences, 100049 Beijing, China
| | - Mei Ma
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 100085 Beijing, China; College of Resources and Environment, University of Chinese Academy of Sciences, 100049 Beijing, China.
| | - Kaifeng Rao
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 100085 Beijing, China
| | - Zijian Wang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 100085 Beijing, China
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Liu Y, Wu D, Xu Q, Yu L, Liu C, Wang J. Acute exposure to tris (2-butoxyethyl) phosphate (TBOEP) affects growth and development of embryo-larval zebrafish. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2017; 191:17-24. [PMID: 28772162 DOI: 10.1016/j.aquatox.2017.07.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 07/22/2017] [Accepted: 07/26/2017] [Indexed: 06/07/2023]
Abstract
Tris (2-butoxyethyl) phosphate (TBOEP), is used as a flame retardant worldwide. It is an additive in materials and can be easily discharged into the surrounding environment. There is evidence linking TBOEP exposure to abnormal development and growth in zebrafish embryos/larvae. Here, using zebrafish embryo as a model, we investigated toxicological effects on developing zebrafish (Danio rerio) caused by TBOEP at concentrations of 0, 20, 200, 1000, 2000μg/L starting from 2h post-fertilization (hpf). Our findings revealed that TBOEP exposure caused developmental toxicity, such as malformation, growth delay and decreased heart rate in zebrafish larvae. Correlation analysis indicated that inhibition of growth was possibly due to down-regulation of expression of genes related to the growth hormone/insulin-like growth factor (GH/IGF) axis. Furthermore, exposure to TBOEP significantly increased thyroxine (T4) and 3,5,3'-triiodothyronine (T3) in whole larvae. In addition, changed expression of genes involved in the hypothalamic-pituitary-thyroid (HPT) axis was observed, indicating that perturbation of HPT axis might be responsible for the developmental damage and growth delay induced by TBOEP. The present study provides a new set of evidence that exposure of embryo-larval zebrafish to TBOEP can cause perturbation of GH/IGF axis and HPT axis, which could result in developmental impairment and growth inhibition.
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Affiliation(s)
- Yiran Liu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Ding Wu
- Department of Urology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China
| | - Qinglong Xu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Liqin Yu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Chunsheng Liu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Jianghua Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China.
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Toxicokinetic of tris(2-butoxyethyl) phosphate (TBOEP) in humans following single oral administration. Arch Toxicol 2017; 92:651-660. [DOI: 10.1007/s00204-017-2078-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 09/21/2017] [Indexed: 10/18/2022]
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21
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Testis Transcriptome Modulation in Klinefelter Patients with Hypospermatogenesis. Sci Rep 2017; 7:45729. [PMID: 28361989 PMCID: PMC5374630 DOI: 10.1038/srep45729] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 03/02/2017] [Indexed: 12/15/2022] Open
Abstract
The main genetic cause of male infertility is represented by the Klinefelter Syndrome (KS), a condition accounting for 3% of all cases of infertility and up to15% of cases of azoospermia. KS is generally characterized by azoospermia; approximately 10% of cases have severe oligozoospermia. Among these, the 30-40% of patients show hypospermatogenesis. The mechanisms leading to adult testis dysfunctions are not completely understood. A microarray transcriptome analysis was performed on testis biopsies obtained from three KS patients with hypospermatogenesis and three control subjects. KS testis showed a differential up- and down-regulation of 303 and 747 transcripts, respectively, as compared to controls. The majority of down-regulated transcripts were involved in spermiogenesis failure and testis morphological defects, whereas up-regulated genes were responsible for testis apoptotic processes. Functional analysis of the transcriptionally altered genes indicated a deregulation in cell death, germ cell function and morphology as well as blood-testis-barrier maintenance and Leydig cells activity. These data support a complex scenario in which spermatogenic impairment is the result of functional and morphological alterations in both germinal and somatic components of KS testis. These findings could represent the basis for evaluating new markers of KS spermatogenesis and potential targets of therapeutic intervention to preserve residual spermatogenesis.
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Xu Q, Wu D, Dang Y, Yu L, Liu C, Wang J. Reproduction impairment and endocrine disruption in adult zebrafish (Danio rerio) after waterborne exposure to TBOEP. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2017; 182:163-171. [PMID: 27912163 DOI: 10.1016/j.aquatox.2016.11.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 11/20/2016] [Accepted: 11/22/2016] [Indexed: 05/03/2023]
Abstract
Tris (2-butoxyethyl) phosphate (TBOEP) is widely used as a substitute of polybrominated diphenyl ethers (PBDEs). It has been frequently measured at concentrations of micrograms per liter (μg/L) in surface waters and waste water. However, limited information is available about the reproduction toxicology of TBOEP. In this study, adult zebrafish pairs were exposed to TBOEP at concentrations of 0, 5, 50, and 500μg/L for 21days. The effects on reproduction, hormone concentration, transcription of genes along the hypothalamic-pituitary-gonadal (HPG) axis, and gonadal development were investigated. After exposure to TBOEP, plasma concentrations of 17β-estradiol were significantly increased in both sexes of fish, while increase of testosterone was observed only in male fish. Transcription of genes along the HPG axis was significantly influenced by exposure to TBOEP in both male and female fish. Moreover, TBOEP decreases the average number of eggs production, as well as hatching success and survival rates in offspring. Histological examination shows inhibition of oocyte maturation in females and retardation spermiation in males, respectively. The results demonstrate that TBOEP could disturb the sex hormone balance by altering regulatory circuits of the HPG axis, affect gonadal development, eventually leading to disruption of reproductive performance and the development of progeny.
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Affiliation(s)
- Qinglong Xu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Ding Wu
- Department of Urology, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China
| | - Yao Dang
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Liqin Yu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China
| | - Chunsheng Liu
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China; Collaborative Innovation Center for Efficient and Health Productioon of Fisherise in Huhan Province, Changde 415000, China; Hubei Provincial Engineering Laboratory for Pond Aquaculture, Wuhan 430070, China
| | - Jianghua Wang
- College of Fisheries, Huazhong Agricultural University, Wuhan 430070, China.
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