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Bullert A, Li X, Gautam B, Wang H, Adamcakova-Dodd A, Wang K, Thorne PS, Lehmler HJ. Distribution of 2,2',5,5'-Tetrachlorobiphenyl (PCB52) Metabolites in Adolescent Rats after Acute Nose-Only Inhalation Exposure. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6105-6116. [PMID: 38547313 PMCID: PMC11008251 DOI: 10.1021/acs.est.3c09527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 02/02/2024] [Accepted: 03/09/2024] [Indexed: 04/10/2024]
Abstract
Inhalation of PCB-contaminated air is increasingly recognized as a route for PCB exposure. Because limited information about the disposition of PCBs following inhalation exposure is available, this study investigated the disposition of 2,2',5,5'-tetrachlorobiphenyl (PCB52) and its metabolites in rats following acute, nose-only inhalation of PCB52. Male and female Sprague-Dawley rats (50-58 days of age, 210 ± 27 g; n = 6) were exposed for 4 h by inhalation to approximately 14 or 23 μg/kg body weight of PCB52 using a nose-only exposure system. Sham animals (n = 6) were exposed to filtered lab air. Based on gas chromatography-tandem mass spectrometry (GC-MS/MS), PCB52 was present in adipose, brain, intestinal content, lung, liver, and serum. 2,2',5,5'-Tetrachlorobiphenyl-4-ol (4-OH-PCB52) and one unknown monohydroxylated metabolite were detected in these compartments except for the brain. Liquid chromatography-high resolution mass spectrometry (LC-HRMS) analysis identified several metabolites, including sulfated, methoxylated, and dechlorinated PCB52 metabolites. These metabolites were primarily found in the liver (7 metabolites), lung (9 metabolites), and serum (9 metabolites) due to the short exposure time. These results demonstrate for the first time that complex mixtures of sulfated, methoxylated, and dechlorinated PCB52 metabolites are formed in adolescent rats following PCB52 inhalation, laying the groundwork for future animal studies of the adverse effects of inhaled PCB52.
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Affiliation(s)
- Amanda
J. Bullert
- Department
of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
- Interdisciplinary
Graduate Program in Neuroscience, The University
of Iowa, Iowa City, Iowa 52242, United States
| | - Xueshu Li
- Department
of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Binita Gautam
- Department
of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Hui Wang
- Department
of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Andrea Adamcakova-Dodd
- Department
of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Kai Wang
- Department
of Biostatistics, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Peter S. Thorne
- Department
of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
- Interdisciplinary
Graduate Program in Neuroscience, The University
of Iowa, Iowa City, Iowa 52242, United States
| | - Hans-Joachim Lehmler
- Department
of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
- Interdisciplinary
Graduate Program in Neuroscience, The University
of Iowa, Iowa City, Iowa 52242, United States
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Wang YY, Luo WK, Tang SX, Xiang J, Dang Y, Tang B, Lu QY, Cai FS, Ren MZ, Yu YJ, Zheng J. Bioaccumulation and biotransformation of 1,2-bis (2,4,6-tribromophenoxyethane) (BTBPE) and 1,2-dibromo-4-(1,2-dibromoethyl)-cyclohexane (TBECH) in zebrafish (Danio rerio). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 345:123460. [PMID: 38290655 DOI: 10.1016/j.envpol.2024.123460] [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: 11/17/2023] [Revised: 01/22/2024] [Accepted: 01/26/2024] [Indexed: 02/01/2024]
Abstract
Despite the increasing production, use, and ubiquitous occurrence of novel brominated flame retardants (NBFRs), little information is available regarding their fate in aquatic organisms. In this study, the bioaccumulation and biotransformation of two typical NBFRs, i.e., 1,2-bis (2,4,6-tribromophenoxyethane) (BTBPE) and 1,2-dibromo-4-(1,2-dibromoethyl)-cyclohexane (TBECH), were investigated in tissues of zebrafish (Danio rerio) being administrated a dose of target chemicals through their diet. Linear accumulation was observed for both BTBPE and TBECH in the muscle, liver, gonads, and brain of zebrafish, and the elimination of BTBPE and TBECH in all tissues followed pseudo-first-order kinetics, with the fastest depuration rate occurring in the liver. BTBPE and TBECH showed low bioaccumulation potential in zebrafish, with biomagnification factors (BMFs) < 1 in all tissues. Individual tissues' function and lipid content are vital factors affecting the distribution of BTBPE and TBECH. Stereoselective accumulation of TBECH enantiomers was observed in zebrafish tissues, with first-eluting enantiomers, i.e. E1-α-TBECH and E1-β-TBECH, preferentially accumulated. Additionally, the transformation products (TPs) in the zebrafish liver were comprehensively screened and identified using high-resolution mass spectrometry. Twelve TPs of BTBPE and eight TPs of TBECH were identified: biotransformation pathways involving ether cleavage, debromination, hydroxylation, and methoxylation reactions for BTBPE and hydroxylation, debromination, and oxidation processes for TBECH. Biotransformation is also a vital factor affecting the bioaccumulation potential of these two NBFRs, and the environmental impacts of NBFR TPs should be further investigated in future studies. The findings of this study provide a scientific basis for an accurate assessment of the ecological and environmental risks of BTBPE and TBECH.
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Affiliation(s)
- Yu-Yu Wang
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
| | - Wei-Keng Luo
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
| | - Song-Xiong Tang
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
| | - Jun Xiang
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
| | - Yao Dang
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
| | - Bin Tang
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China.
| | - Qi-Yuan Lu
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
| | - Feng-Shan Cai
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
| | - Ming-Zhong Ren
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
| | - Yun-Jiang Yu
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
| | - Jing Zheng
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, Research Center of Emerging Contaminants, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510530, PR China
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He W, Cui Y, Yang H, Gao J, Zhao Y, Hao N, Li Y, Zhang M. Aquatic toxicity, ecological effects, human exposure pathways and health risk assessment of liquid crystal monomers. JOURNAL OF HAZARDOUS MATERIALS 2024; 461:132681. [PMID: 37801980 DOI: 10.1016/j.jhazmat.2023.132681] [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: 07/27/2023] [Revised: 09/19/2023] [Accepted: 09/29/2023] [Indexed: 10/08/2023]
Abstract
Liquid crystal monomers (LCMs), one of the key materials for liquid crystal displays, have been considered as emerging pollutants in recent years. However, the environmental behaviors of LCMs have not yet been well investigated. The toxicity data of 1173 LCMs were calculated by integrated computational simulation methods in this study. It showed that 64.6% LCMs exhibited PBT (persistent, bioaccumulative, and toxic) properties. Based on the results, 1173 LCMs were identified as molecules possessing the highest level of acute toxicity to aquatic organisms. Among which, and a human health risk priority control list about LCMs was generated in this study, among which 435 were classified as requiring priority control LCMs. It was confirmed that LCMs could eventually accumulate in the human body along the aquatic food chain or penetrate the bloodstream through the dermis, thereby causing harm to health by identifying the exposure pathways of LCMs in humans. Additionally, the electronegativity of the side chain group of LCMs is the main factor causing toxicity differences; therefore, the LCMs containing halogens presented significant acute and chronic toxic effects. This study provided a more comprehensive understanding of LCMs for the public and scientific strategies for controlling LCMs.
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Affiliation(s)
- Wei He
- MOE Key Laboratory of Resources Environmental Systems Optimization, North China Electric Power University, Beijing 102206, China
| | - Yuhan Cui
- MOE Key Laboratory of Resources Environmental Systems Optimization, North China Electric Power University, Beijing 102206, China
| | - Hao Yang
- MOE Key Laboratory of Resources Environmental Systems Optimization, North China Electric Power University, Beijing 102206, China
| | - Jiaxuan Gao
- MOE Key Laboratory of Resources Environmental Systems Optimization, North China Electric Power University, Beijing 102206, China
| | - Yuanyuan Zhao
- MOE Key Laboratory of Resources Environmental Systems Optimization, North China Electric Power University, Beijing 102206, China
| | - Ning Hao
- College of New Energy and Environment, Jilin University, Changchun 130012, China
| | - Yu Li
- MOE Key Laboratory of Resources Environmental Systems Optimization, North China Electric Power University, Beijing 102206, China
| | - Meng Zhang
- College of Environmental Sciences and Engineering, State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, Peking University, Beijing 100871, China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, International Joint Laboratory for Regional Pollution Control, Ministry of Education, Beijing 100871, China.
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4
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Wang H, Bullert AJ, Li X, Stevens H, Klingelhutz AJ, Ankrum JA, Adamcakova-Dodd A, Thorne PS, Lehmler HJ. Use of a polymeric implant system to assess the neurotoxicity of subacute exposure to 2,2',5,5'-tetrachlorobiphenyl-4-ol, a human metabolite of PCB 52, in male adolescent rats. Toxicology 2023; 500:153677. [PMID: 37995827 PMCID: PMC10757425 DOI: 10.1016/j.tox.2023.153677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/06/2023] [Accepted: 11/18/2023] [Indexed: 11/25/2023]
Abstract
Polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) that ubiquitously exist in the environment. PCB exposure has been linked to cancer and multi-system toxicity, including endocrine disruption, immune inhibition, and reproductive and neurotoxicity. 2,2',5,5'-Tetrachlorobiphenyl (PCB 52) is one of the most frequently detected congeners in the environment and human blood. The hydroxylated metabolites of PCB 52 may also be neurotoxic, especially for children whose brains are still developing. However, it is challenging to discern the contribution of these metabolites to PCB neurotoxicity because the metabolism of PCB is species-dependent. In this study, we evaluated the subacute neurotoxicity of a human-relevant metabolite, 2,2',5,5'-tetrachlorobiphenyl-4-ol (4-52), on male adolescent Sprague Dawley rats, via a novel polymeric implant drug delivery system grafted subcutaneously, at total loading concentrations ranging from 0%, 1%, 5%, and 10% of the implant (w/w) for 28 days. Y-maze, hole board test, open field test, and elevated plus maze were performed on exposure days 24-28 to assess their locomotor activity, and exploratory and anxiety-like behavior. 4-52 and other possible hydroxylated metabolites in serum and vital tissues were quantified using gas chromatography with tandem mass spectrometry (GC-MS/MS). Our results demonstrate the sustained release of 4-52 from the polymeric implants into the systemic circulation in serum and tissues. Dihydroxylated and dechlorinated metabolites were detected in serum and tissues, depending on the dose and tissue type. No statistically significant changes were observed in the neurobehavioral tasks across all exposure groups. The results demonstrate that subcutaneous polymeric implants provide a straightforward method to expose rats to phenolic PCB metabolites to study neurotoxic outcomes, e.g., in memory, anxiety, and exploratory behaviors.
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Affiliation(s)
- Hui Wang
- Department of Occupational and Environmental Health, the University of Iowa, Iowa City, IA, USA
| | - Amanda J Bullert
- Department of Occupational and Environmental Health, the University of Iowa, Iowa City, IA, USA; Interdisciplinary Graduate Program in Neuroscience, the University of Iowa, Iowa City, IA, USA
| | - Xueshu Li
- Department of Occupational and Environmental Health, the University of Iowa, Iowa City, IA, USA
| | - Hanna Stevens
- Interdisciplinary Graduate Program in Neuroscience, the University of Iowa, Iowa City, IA, USA; Department of Psychiatry, the University of Iowa, Iowa City, IA, USA; Interdisciplinary Graduate Program in Human Toxicology, the University of Iowa, Iowa City, IA, USA
| | | | - James A Ankrum
- Roy J. Carver Department of Biomedical Engineering, the University of Iowa, Iowa City, IA, USA
| | - Andrea Adamcakova-Dodd
- Department of Occupational and Environmental Health, the University of Iowa, Iowa City, IA, USA
| | - Peter S Thorne
- Department of Occupational and Environmental Health, the University of Iowa, Iowa City, IA, USA; Interdisciplinary Graduate Program in Neuroscience, the University of Iowa, Iowa City, IA, USA; Interdisciplinary Graduate Program in Human Toxicology, the University of Iowa, Iowa City, IA, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, the University of Iowa, Iowa City, IA, USA; Interdisciplinary Graduate Program in Neuroscience, the University of Iowa, Iowa City, IA, USA; Interdisciplinary Graduate Program in Human Toxicology, the University of Iowa, Iowa City, IA, USA.
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5
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Li X, Bullert AJ, Han W, Yang W, Zhang QY, Ding X, Lehmler HJ. Enantiomeric Fractions Reveal Differences in the Atropselective Disposition of 2,2',3,5',6-Pentachlorobiphenyl (PCB 95) in Wildtype, Cyp2abfgs-Null, and CYP2A6-Humanized Mice. Chem Res Toxicol 2023; 36:1386-1397. [PMID: 37467352 PMCID: PMC10445290 DOI: 10.1021/acs.chemrestox.3c00128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Indexed: 07/21/2023]
Abstract
Polychlorinated biphenyls (PCBs) are environmental contaminants that can cause neurotoxicity. PCBs, such as PCB 95 (2,2',3,5',6-pentachlorobiphenyl), can be metabolized by cytochrome P450 enzymes into neurotoxic metabolites. To better understand how the metabolism of PCB 95 affects neurotoxic outcomes, we conducted a study on the disposition of PCB 95 in transgenic mouse models. The mice were given a single oral dose of PCB 95 (1.0 mg/kg) and were euthanized 24 h later for analysis. PCB 95 levels were highest in adipose tissue, followed by the liver, brain, and blood. Adipose tissue levels were significantly higher in wild-type (WT) mice than in Cyp2abfgs-null (KO) or CYP2A6-transgenic (KI) mice. We also observed genotype-dependent differences in the enrichment of aS-PCB 95 in female mice, with a less pronounced enrichment in KO than WT and KI mice. Ten hydroxylated PCB 95 metabolites were detected in blood and tissue across all exposure groups. The metabolite profiles differed across tissues, while sex and genotype-dependent differences were less pronounced. Total OH-PCB levels were highest in the blood, followed by the liver, adipose tissue, and brain. Total OH-PCB blood levels were lower in KO than in WT mice, while the opposite trend was observed in the liver. In male mice, total OH-PCB metabolite levels were significantly lower in KI than in WT mice in blood and the liver, while the opposite trend was observed in female mice. In conclusion, the study highlights the differences in the atropselective disposition of PCB 95 and its metabolites in different types of mice, demonstrating the usefulness of these transgenic mouse models for characterizing the role of PCB metabolism in PCB neurotoxicity.
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Affiliation(s)
- Xueshu Li
- Department
of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, Iowa 52242, United States
| | - Amanda J. Bullert
- Department
of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, Iowa 52242, United States
- Interdisciplinary
Graduate Program in Neuroscience, University
of Iowa, Iowa City, Iowa 52242, United States
| | - Weiguo Han
- Department
of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
| | - Weizhu Yang
- Department
of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
| | - Qing-Yu Zhang
- Department
of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
| | - Xinxin Ding
- Department
of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, United States
| | - Hans-Joachim Lehmler
- Department
of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, Iowa 52242, United States
- Interdisciplinary
Graduate Program in Neuroscience, University
of Iowa, Iowa City, Iowa 52242, United States
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Lehmler HJ, Uwimana E, Dean LE, Kovalchuk N, Zhang QY, Ding X. Probing the Role of CYP2 Enzymes in the Atropselective Metabolism of Polychlorinated Biphenyls Using Liver Microsomes from Transgenic Mouse Models. Chem Res Toxicol 2022; 35:2310-2323. [PMID: 36473170 PMCID: PMC9957597 DOI: 10.1021/acs.chemrestox.2c00276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Chiral polychlorinated biphenyls (PCB) are environmentally relevant developmental neurotoxicants. Because their hydroxylated metabolites (OH-PCBs) are also neurotoxic, it is necessary to determine how PCB metabolism affects the developing brain, for example, in mouse models. Because the cytochrome P450 isoforms involved in the metabolism of chiral PCBs remain unexplored, we investigated the metabolism of PCB 91 (2,2',3,4',6-pentachlorobiphenyl), PCB 95 (2,2',3,5',6-pentachlorobiphenyl), PCB 132 (2,2',3,3',4,6'-hexachlorobiphenyl), and PCB 136 (2,2',3,3',6,6'-hexachlorobiphenyl) using liver microsomes from male and female Cyp2a(4/5)bgs-null, Cyp2f2-null, and wild-type mice. Microsomes, pooled by sex, were incubated with 50 μM PCB for 30 min, and the levels and enantiomeric fractions of the OH-PCBs were determined gas chromatographically. All four PCB congeners appear to be atropselectively metabolized by CYP2A(4/5)BGS and CYP2F2 enzymes in a congener- and sex-dependent manner. The OH-PCB metabolite profiles of PCB 91 and PCB 132, PCB congeners with one para-chlorine substituent, differed between null and wild-type mice. No differences in the metabolite profiles were observed for PCB 95 and PCB 136, PCB congeners without a para-chlorine group. These findings suggest that Cyp2a(4/5)bgs-null and Cyp2f2-null mice can be used to study how a loss of a specific metabolic function (e.g., deletion of Cyp2a(4/5)bgs or Cyp2f2) affects the toxicity of chiral PCB congeners.
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Affiliation(s)
- Hans-Joachim Lehmler
- Interdisciplinary Graduate Program in Human Toxicology and Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52242, United States
| | - Eric Uwimana
- Interdisciplinary Graduate Program in Human Toxicology and Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52242, United States
| | - Laura E. Dean
- Interdisciplinary Graduate Program in Human Toxicology and Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52242, United States
| | - Nataliia Kovalchuk
- Department of Pharmacology & Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ 85721, United States
| | - Qing-Yu Zhang
- Department of Pharmacology & Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ 85721, United States
| | - Xinxin Ding
- Department of Pharmacology & Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ 85721, United States
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Inui H, Ito T, Miwa C, Haga Y, Kubo M, Itoh T, Yamamoto K, Miyaoka M, Mori T, Tsuzuki H, Mise S, Goto E, Matsumura C, Nakano T. Differences in Enantioselective Hydroxylation of 2,2',3,6-Tetrachlorobiphenyl (CB45) and 2,2',3,4',6-Pentachlorobiphenyl (CB91) by Human and Rat CYP2B Subfamilies. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:10204-10215. [PMID: 35801261 DOI: 10.1021/acs.est.2c01155] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Although polychlorinated biphenyls (PCBs) were commercially banned half a century ago, contamination of the environment and organisms by PCBs is still observed. PCBs show high persistence and bioaccumulation, resulting in toxicity. Among PCBs, chiral PCBs with more than three chlorine atoms at the ortho-position exhibit developmental and neurodevelopmental toxicity. Because toxicity is dependent on the atropisomer, atropisomer-specific metabolism is vital in determining toxicity. However, structural information on enantioselective metabolism remains elusive. Cytochrome P450 (CYP, P450) monooxygenases, particularly human CYP2B6 and rat CYP2B1, metabolize separated atropisomers of 2,2',3,6-tetrachlorobiphenyl (CB45) and 2,2',3,4',6-pentachlorobiphenyl (CB91) to dechlorinated and hydroxylated metabolites. Docking studies using human CYP2B6 predict 4'-hydroxy (OH)-CB45 from (aR)-CB45 as a major metabolite of CB45. Di-OH- and dechlorinated OH-metabolites from human CYP2B6 and rat CYP2B1 are also detected. Several hydroxylated metabolites are derived from CB91 by both P450s; 5-OH-CB91 is predicted as a major metabolite. CB91 dechlorination is also detected by identifying 3-OH-CB51. A stable conformation of PCBs in the substrate-binding cavity and close distance to P450 heme are responsible for high metabolizing activities. As hydroxylation and dechlorination change PCB toxicity, this approach helps understand the possible toxicity of chiral PCBs in mammals.
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Affiliation(s)
- Hideyuki Inui
- Biosignal Research Center, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan
- Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Terushi Ito
- Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Chiharu Miwa
- Faculty of Agriculture, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Yuki Haga
- Hyogo Prefectural Institute of Environmental Sciences, 3-1-18 Yukihiracho, Suma-ku, Kobe, Hyogo 654-0037, Japan
| | - Makoto Kubo
- Laboratory of Drug Design and Medicinal Chemistry, Showa Pharmaceutical University, 3-3165 Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan
| | - Toshimasa Itoh
- Laboratory of Drug Design and Medicinal Chemistry, Showa Pharmaceutical University, 3-3165 Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan
| | - Keiko Yamamoto
- Laboratory of Drug Design and Medicinal Chemistry, Showa Pharmaceutical University, 3-3165 Higashi-Tamagawagakuen, Machida, Tokyo 194-8543, Japan
| | - Masayuki Miyaoka
- Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Tadashi Mori
- Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Harunobu Tsuzuki
- Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Shintaro Mise
- Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Erika Goto
- Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Chisato Matsumura
- Hyogo Prefectural Institute of Environmental Sciences, 3-1-18 Yukihiracho, Suma-ku, Kobe, Hyogo 654-0037, Japan
| | - Takeshi Nakano
- Research Center for Environmental Preservation, Osaka University, 2-4 Yamadaoka, Suita, Osaka 565-0871, Japan
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Abu-Bakar A, Tan BH, Halim H, Ramli S, Pan Y, Ong6 CE. Cytochromes P450: Role in Carcinogenesis and Relevance to Cancers. Curr Drug Metab 2022; 23:355-373. [DOI: 10.2174/1389200223666220328143828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 12/06/2021] [Accepted: 01/25/2022] [Indexed: 11/22/2022]
Abstract
Abstracts:
Cancer is a leading factor of mortality globally. Cytochrome P450 (CYP) enzymes play a pivotal role in the biotransformation of both endogenous and exogenous compounds. Evidence from numerous epidemiological, animal, and clinical studies points to instrumental role of CYPs in cancer initiation, metastasis, and prevention. Substantial research has found that CYPs are involved in activating different carcinogenic chemicals in the environment, such as polycyclic aromatic hydrocarbons and tobacco-related nitrosamines. Electrophilic intermediates produced from these chemicals can covalently bind to DNA, inducing mutation and cellular transformation that collectively result in cancer development. While bioactivation of procarcinogens and promutagens by CYPs has long been established, the role of CYP-derived endobiotics in carcinogenesis has emerged in recent years. Eicosanoids derived from arachidonic acid via CYP oxidative pathways have been implicated in tumorigenesis, cancer progression and metastasis. The purpose of this review is to update on the current state of knowledge about the cancer molecular mechanism involving CYPs with focus on the biochemical and biotransformation mechanisms in the various CYP-mediated carcinogenesis, and the role of CYP-derived reactive metabolites, from both external and endogenous sources, on cancer growth and tumour formation.
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Affiliation(s)
- A’edah Abu-Bakar
- Product Stewardship and Toxicology, Group Health, Safety, Security and Environment, PETRONAS, Kuala Lumpur, Malaysia
| | - Boon Hooi Tan
- Division of Applied Biomedical Sciences and Biotechnology, International Medical University, Bukit Jalil, Kuala Lumpur, Malaysia
| | - Hasseri Halim
- Faculty of Pharmacy, Universiti Teknologi MARA, Selangor, 42300 Puncak Alam, Selangor, Malaysia
| | - Salfarina Ramli
- Faculty of Pharmacy, Universiti Teknologi MARA, Selangor, 42300 Puncak Alam, Selangor, Malaysia
| | - Yan Pan
- Department of Biomedical Science, University of Nottingham Malaysia Campus, Semenyih, Selangor, Malaysia
| | - Chin Eng Ong6
- School of Pharmacy, International Medical University, Bukit Jalil, Kuala Lumpur, Malaysia
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9
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Megson D, Brown T, Jones GR, Robson M, Johnson GW, Tiktak GP, Sandau CD, Reiner EJ. Polychlorinated biphenyl (PCB) concentrations and profiles in marine mammals from the North Atlantic Ocean. CHEMOSPHERE 2022; 288:132639. [PMID: 34687677 DOI: 10.1016/j.chemosphere.2021.132639] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 10/16/2021] [Accepted: 10/19/2021] [Indexed: 06/13/2023]
Abstract
Polychlorinated biphenyls (PCBs) can provide crucial information into the bioaccumulation and biomagnification of POPs in marine mammals. Muscle tissue samples were obtained for detailed PCB congener specific analysis of all 209 PCBs in 11 species of marine mammals stranded across the coast of the UK between 2010 and 2013. At least 145 PCB congeners were found in each individual. The highest concentrations of PCBs were recorded in a killer whale (318 mg/kg lipid) and the highest toxic equivalent in a Risso's dolphin (1687 pg/g TEQ2005 wet). Concentrations of PCBs in the majority of samples exceeded toxic thresholds (9 mg/kg lipid) for marine mammals, highlighting the health risk they face from PCB exposure. Many PCB profiles did not fit typical 'Aroclor' signatures, but instead indicated patterns of congeners that are resistant to biotransformation and elimination. However, this study identified a novel PCB signature in a sei whale that has not yet been previously observed in marine mammals. The whale had a PCB profile that included lighter and inadvertent PCB congeners such as PCB 11, suggesting that the main source of exposure was through atmospheric deposition, rather than terrestrial discharges. Seven subsamples were chosen for chiral analysis of PCB 95, 136 and 149. The enantiomer fractions (EFs) of C-PCBs 95 and 149 were non racemic suggesting there may be enantiomer selective metabolism in marine mammals. Although there has been a shift in the literature towards emerging pollutants, this study acts as a stark reminder that PCBs continue to pose a significant risk to wildlife.
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Affiliation(s)
- David Megson
- Manchester Metropolitan University, Ecology & Environment Research Centre, Department of Natural Science, Manchester, UK; Chemistry Matters, Calgary, AB, Canada.
| | - Thomas Brown
- Scottish Association for Marine Science (SAMS), Oban, Scotland, UK
| | | | - Mathew Robson
- Ontario Ministry of the Environment, Conservation and Parks. 125 Resources Road, Toronto, ON, M9P 3V6, Canada
| | | | - Guuske P Tiktak
- Manchester Metropolitan University, Ecology & Environment Research Centre, Department of Natural Science, Manchester, UK
| | | | - Eric J Reiner
- Ontario Ministry of the Environment, Conservation and Parks. 125 Resources Road, Toronto, ON, M9P 3V6, Canada
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10
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Wang MY, Zhang LF, Wu D, Cai YQ, Huang DM, Tian LL, Fang CL, Shi YF. Simulation experiment on OH-PCB being ingested through daily diet: Accumulation, transformation and distribution of hydroxylated-2, 2', 4, 5, 5'-pentachlorobiphenyl (OH-PCB101) in mice. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 802:149891. [PMID: 34474296 DOI: 10.1016/j.scitotenv.2021.149891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 08/06/2021] [Accepted: 08/21/2021] [Indexed: 05/16/2023]
Abstract
Animals exposure to polychlorinated biphenyls (PCBs) may result in retention of hydroxylated PCBs (OH-PCBs). OH-PCBs can be accumulated in animals, including humans, through the transmission of food chain. However, there are few studies on the accumulation and metabolism of OH-PCBs exposed to the body through daily diet. Therefore, this study was conducted to investigate the fate of OH-PCBs after being ingested through dietary intake. By adding 3-OH-PCB101 and 4-OH-PCB101 to the edible tissue of crucian carp, which were used as raw materials to prepare mouse feed, with an exposure concentration of 2.5 μg/kg ww. The exposure experiment lasted for a total of 80 days. The blood, feces and 11 tissues of mice at different times were analyzed qualitatively and quantitatively. It was found that major OH-PCB101 were accumulated in intestine or excreted with feces. A small part was accumulated in heart, lung and spleen. For the first time that the conversion from OH-PCB101 to PCB101 in mice was discovered, which shows from another perspective that persistent organic pollutants are difficult to be completely degraded in the environment. 4-MeO-PCB101, 3-MeSO2-PCB101, and 4-MeSO2-PCB101 were also found in various tissues. The results of this study show that after OH-PCBs accumulated in animals re-enter the organism through the food chain, they can be metabolized again and may be reversely transformed into the parent compounds. The present research shed new light on simulating the metabolic transformation process of OH-PCBs exposed to mammals through ingestion of fish. Available data show that second-generation persistent organic pollutants in the environment still need to be continuously concerned.
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Affiliation(s)
- Meng-Yuan Wang
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, Shanghai 200090, China; College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Long-Fei Zhang
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, Shanghai 200090, China; College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Di Wu
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, Shanghai 200090, China; College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
| | - You-Qiong Cai
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, Shanghai 200090, China
| | - Dong-Mei Huang
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, Shanghai 200090, China
| | - Liang-Liang Tian
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, Shanghai 200090, China
| | - Chang-Ling Fang
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, Shanghai 200090, China
| | - Yong-Fu Shi
- Fishery Products Quality Inspection and Test Centre (Shanghai), East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs of China, Shanghai 200090, China.
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11
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Chu X, Bu Y, Yang X. Recent Research Progress of Chiral Small Molecular Antitumor-Targeted Drugs Approved by the FDA From 2011 to 2019. Front Oncol 2021; 11:785855. [PMID: 34976824 PMCID: PMC8718447 DOI: 10.3389/fonc.2021.785855] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 11/25/2021] [Indexed: 12/15/2022] Open
Abstract
Chiral drugs usually contain chiral centers, which are present as single enantiomers or racemates. Compared with achiral drugs, they have significant advantages in safety and efficacy with high stereoselectivity. Of these drugs, chirality not only exerts influence on the solubility and pharmacokinetic characteristics but also has specific mechanistic characteristics on their targets. We noted that small molecules with unique chiral properties have emerged as novel components of antitumor drugs approved by the FDA in decade. Since approved, these drugs have been continuously explored for new indications, new mechanisms, and novel combinations. In this mini review, recent research progress of twenty-two FDA-approved chiral small molecular-targeted antitumor drugs from 2011 to 2019 is summarized with highlighting the potential and advantages of their applications. We believe that these updated achievements may provide theoretical foundation and stimulate research interests for optimizing drug efficacy, expanding clinical application, overcoming drug resistance, and advancing safety in future clinical administrations of these chiral targeted drugs.
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Affiliation(s)
| | | | - Xiaoping Yang
- Key Laboratory of Study and Discovery of Small Targeted Molecules of Hunan Province, Department of Pharmacy, School of Medicine, Hunan Normal University, Changsha, China
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12
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Zhu L, Huo X, Zhou J, Zhang Q, Wang W. Metabolic activation mechanism of 2,2',3,3',6,6'-hexachlorobiphenyl (PCB136) by cytochrome P450 2B6: A QM/MM approach. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 776:145579. [PMID: 33652317 DOI: 10.1016/j.scitotenv.2021.145579] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 01/28/2021] [Accepted: 01/28/2021] [Indexed: 06/12/2023]
Abstract
Cytochrome P450 enzymes (CYPs) play an essential role in the bio-transformation of polychlorinated biphenyls (PCBs). The present work implemented quantum mechanic/molecular mechanic methods (QM/MM) and density functional theory (DFT) to study the metabolic activation of 2,2',3,3',6,6'-hexachlorobiphenyl (PCB136) catalyzed by CYP2B6. Electrophilic additions at the Cα and Cβ positions generate different active intermediates. The electrophilic addition energy barrier of Cβ is 10.9 kcal/mol higher than that of Cα, and Cα is the preferred site for the electrophilic addition reaction. Based on the previous experimental studies, this work investigated the mechanism of converting active intermediates into OH-PCB136, which has high toxicity in a non-enzymatic environment. Structural analysis via the electrostatic and noncovalent interactions indicates that Phe108, Ile114, Phe115, Phe206, Phe297, Ala298, Leu363, Val367, TIP32475 and TIP32667 play crucial roles in substrate recognition and metabolism. The analysis suggests that the halogen-π interactions are important factors for the metabolism of CYP2B6 to halogenated environmental pollutants. This work improved the understanding of the metabolism and activation process of chiral PCBs, and can be used as a guide to improve the microbial degradation efficiency of PCB136.
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Affiliation(s)
- Ledong Zhu
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Xinxi Huo
- Environment Research Institute, Shandong University, Qingdao 266237, PR China; Office of Supervisory and Audit, Shandong University, Qingdao 266237, PR China
| | - Jie Zhou
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Qingzhu Zhang
- Environment Research Institute, Shandong University, Qingdao 266237, PR China.
| | - Wenxing Wang
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
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13
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Dai S, Qiu J, Wang M. Concentration-dependent enantioselective accumulation of chiral polychlorinated biphenyls in Nelumbo nucifera Gaertn. root from contaminative sediment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:27878-27884. [PMID: 33517550 DOI: 10.1007/s11356-021-12530-8] [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: 07/15/2020] [Accepted: 01/13/2021] [Indexed: 06/12/2023]
Abstract
Nelumbo nucifera Gaertn. (lotus) roots were collected from contaminated sediments which were artificially adding different concentrations of chiral polychlorinated biphenyls (PCBs) to investigate the effect of concentration on the accumulation characteristics and chiral signatures of PCBs in lotus root during its growth period of 150 days. Under high PCB exposure concentration, the biota-sediment accumulation factors (BSAFs) of PCBs 91, 95, and 136 in the lotus root were up to 0.25-0.46 and 8.10-10.5 times higher than those under low-exposure concentration (0.024-0.052). The BSAFs of PCBs 149, 176, and 183 under high-exposure concentration were up to 0.24-0.44, while they were undetected at low concentration. The significant difference observed in the BSAFs based on different concentrations indicates that the lotus root accumulation efficiency toward chiral PCBs increases with the contaminate concentration. Although the (-)-enantiomers of PCBs 91, 95, and 136 were all preferentially accumulated in lotus root under two exposure concentrations, the extent of the preferential accumulation of (-)-PCB 95 decreased with increasing exposure concentration throughout the whole growth period (30-150 days). In addition, the (-)-enantiomers of PCBs 91 and 136 also showed the same tendency during most of the growth period. Conclusively, the exposure concentrations are an important influence factor on the enantioselective accumulation of chiral PCBs in lotus root.
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Affiliation(s)
- Shouhui Dai
- Equipment Public Service Center, Key Laboratory of Tropical Marine Bio-Resources and Ecology South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, People's Republic of China.
| | - Jing Qiu
- Institute of Quality Standard & Testing Technology for Agro-Products, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Min Wang
- Institute of Quality Standard & Testing Technology for Agro-Products, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
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14
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Zhang CY, Klocke CR, Lein PJ, Lehmler HJ. Disposition of PCB 11 in Mice Following Acute Oral Exposure. Chem Res Toxicol 2021; 34:988-991. [PMID: 33734669 DOI: 10.1021/acs.chemrestox.1c00067] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PCB 11 (3,3'-dichloro-biphenyl) is an emerging environmental contaminant that represents a public health concern. Here, we investigated the distribution of PCB 11 and its metabolites in mice exposed orally to PCB 11. PCB 11 tissue levels followed the rank order adipose > lung ∼ muscle > liver > brain > blood 4 h after PCB 11 exposure, which varied from the rank order predicted with a composition-based model. We detected hydroxylated and sulfate metabolites in the liver and sulfate and glucuronide metabolites in serum. These findings lay the groundwork for future toxicity studies with PCB 11.
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Affiliation(s)
- Chun-Yun Zhang
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, Iowa 52242-5000, United States
| | - Carolyn R Klocke
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, California 95616, United States
| | - Pamela J Lein
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, California 95616, United States
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, Iowa 52242-5000, United States
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15
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Sokal A, Jarmakiewicz-Czaja S, Tabarkiewicz J, Filip R. Dietary Intake of Endocrine Disrupting Substances Presents in Environment and Their Impact on Thyroid Function. Nutrients 2021; 13:867. [PMID: 33800806 PMCID: PMC7998837 DOI: 10.3390/nu13030867] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 02/28/2021] [Accepted: 03/03/2021] [Indexed: 12/11/2022] Open
Abstract
According to the available data, environmental pollution is a serious problem all over the world. Between 2015 and 2016, pollution was responsible for approximately nine million deaths worldwide. They also include endocrine disrupting chemicals (EDCs) that can interfere with the functioning of the thyroid gland. They are characterized by high persistence in the environment. These substances can enter the body through the gastrointestinal tract, respiratory system, as well as contact with the skin and overcome the placental barrier. EDC can be found in food, water, and personal care products. They can get into food from the environment and as a result of their migration to food products and cosmetics from packaging. EDCs can disrupt the functioning of the thyroid gland through a number of mechanisms, including disrupting the activation of thyroid receptors and the expression of genes that are related to the metabolism, synthesis, and transport of thyroid hormones (HT). There is a need to strengthen the food safety policy that aimed at the use of appropriate materials in direct contact with food. At the same time, an important action is to reduce the production of all waste and, when possible, use biodegradable packaging, which may contribute to the improvement of the quality of the entire ecosystem and the health of food, thus reducing the risk of developing thyroid diseases.
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Affiliation(s)
- Aneta Sokal
- Institute of Health Sciences, Medical College of Rzeszow University, 35-959 Rzeszow, Poland;
| | - Sara Jarmakiewicz-Czaja
- Institute of Health Sciences, Medical College of Rzeszow University, 35-959 Rzeszow, Poland;
| | - Jacek Tabarkiewicz
- Institute of Medicine, Medical College of Rzeszow University, 35-959 Rzeszow, Poland; (J.T.); (R.F.)
| | - Rafał Filip
- Institute of Medicine, Medical College of Rzeszow University, 35-959 Rzeszow, Poland; (J.T.); (R.F.)
- Department of Gastroenterology with IBD Unit, Clinical Hospital No. 2, 35-301 Rzeszow, Poland
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16
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Qin Q, Yang B, Liu Z, Xu L, Song E, Song Y. Polychlorinated biphenyl quinone induced the acquisition of cancer stem cells properties and epithelial-mesenchymal transition through Wnt/β-catenin. CHEMOSPHERE 2021; 263:128125. [PMID: 33297114 DOI: 10.1016/j.chemosphere.2020.128125] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 08/20/2020] [Accepted: 08/24/2020] [Indexed: 06/12/2023]
Abstract
Polychlorinated biphenyls (PCBs) are persistent industrial pollutants that have been linked to breast cancer progression. However, their molecular mechanism(s) are currently unclear. Our previous assessment suggested that the highly reactive PCB metabolite 2,3,5-trichloro-6-phenyl-[1,4]-benzoquinone (PCB29-pQ) induces the metastasis of breast cancer. Here, our data illustrate that PCB29-pQ increases cancer stem cell (CSC) marker expression, resulting in an increase in the epithelial-mesenchymal transition (EMT) in MDA-MB-231 breast cancer cells; further, the Wnt/β-catenin pathway also becomes activated by PCB29-pQ. When the Wnt/β-catenin pathway is inhibited, the promotion of CSC properties and EMT by PCB29-pQ were accordingly reversed. In addition, the overproduction of reactive oxygen species (ROS) mediated by PCB29-pQ plays a key role in Wnt/β-catenin activation. Collectively, our current data designated the regulatory role of Wnt/β-catenin in PCB29-pQ-triggered acquisition of CSC properties and EMT.
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Affiliation(s)
- Qi Qin
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Bingwei Yang
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Zixuan Liu
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Lei Xu
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Erqun Song
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People's Republic of China
| | - Yang Song
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, People's Republic of China.
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17
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Li X, Liu Y, Martin JW, Cui JY, Lehmler HJ. Nontarget analysis reveals gut microbiome-dependent differences in the fecal PCB metabolite profiles of germ-free and conventional mice. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 268:115726. [PMID: 33032095 PMCID: PMC7746632 DOI: 10.1016/j.envpol.2020.115726] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/22/2020] [Accepted: 09/24/2020] [Indexed: 05/18/2023]
Abstract
Mammalian polychlorinated biphenyl (PCB) metabolism has not been systematically explored with nontarget high-resolution mass spectrometry (Nt-HRMS). Here we investigated the importance of the gut microbiome in PCB biotransformation by Nt-HRMS analysis of feces from conventional (CV) and germ-free (GF) adult female mice exposed to a single oral dose of an environmental PCB mixture (6 mg/kg or 30 mg/kg in corn oil). Feces were collected for 24 h after PCB administration, PCB metabolites were extracted from pooled samples, and the extracts were analyzed by Nt-HRMS. Twelve classes of PCB metabolites were detected in the feces from CV mice, including PCB sulfates, hydroxylated PCB sulfates (OH-PCB sulfates), PCB sulfonates, and hydroxylated methyl sulfone PCBs (OH-MeSO2-PCBs) reported previously. We also observed eight additional PCB metabolite classes that were tentatively identified as hydroxylated PCBs (OH-PCBs), dihydroxylated PCBs (DiOH-PCBs), monomethoxylated dihydroxylated PCBs (MeO-OH-PCBs), methoxylated PCB sulfates (MeO-PCB sulfates), mono-to tetra-hydroxylated PCB quinones ((OH)x-quinones, x = 1-4), and hydroxylated polychlorinated benzofurans (OH-PCDF). Most metabolite classes were also detected in the feces from GF mice, except for MeO-OH-PCBs, OH-MeSO2-PCBs, and OH-PCDFs. Semi-quantitative analyses demonstrate that relative PCB metabolite levels increased with increasing dose and were higher in CV than GF mice, except for PCB sulfates and MeO-PCB sulfates, which were higher in GF mice. These findings demonstrate that the gut microbiome plays a direct or indirect role in the absorption, distribution, metabolism, or excretion of PCB metabolites, which in turn may affect toxic outcomes following PCB exposure.
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Affiliation(s)
- Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, IA, 52242-5000, USA
| | - Yanna Liu
- Division of Analytical and Environmental Toxicity, Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, T6G 2G3, Canada
| | - Jonathan W Martin
- Science for Life Laboratory, Department of Environmental Science, Stockholm University, Stockholm, 114 18, Sweden
| | - Julia Yue Cui
- Department of Environmental & Occupational Health Sciences, University of Washington, Seattle, WA, 98105-6099, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, IA, 52242-5000, USA.
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18
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Zhang CY, Flor S, Ludewig G, Lehmler HJ. Atropselective Partitioning of Polychlorinated Biphenyls in a HepG2 Cell Culture System: Experimental and Modeling Results. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:13817-13827. [PMID: 33059451 PMCID: PMC7642102 DOI: 10.1021/acs.est.0c02508] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Cell culture models are used to study the toxicity of polychlorinated biphenyls (PCBs); however, it is typically unknown how much PCB enters the cells and, for chiral PCBs, if the partitioning is atropselective. We investigated the partitioning of racemic PCB 91, PCB 95, PCB 132, and PCB 136 in HepG2 cells following a 72 h incubation. PCBs were present in the cell culture medium (60.7-88.8%), cells (8.0-14.6%), and dishes (2.3-7.8%) and displayed atropisomeric enrichment in the cells (enantiomeric fraction [EF] = 0.55-0.77) and dishes (EF = 0.53-0.68). Polyparameter linear free energy relationships coupled with a composition-based model provided a good estimate of the PCB levels in the cells and cell culture medium. The free concentration was subsequently used to extrapolate from the nominal cell culture concentration to PCB tissue levels and vice versa. This approach can be used for in vitro-in vivo extrapolations for all 209 PCB congeners. However, this model (and modified models based on descriptors incorporating atropselective interactions, i.e., relative retention times on chiral columns) did not predict the atropselective partitioning in the cell culture system. Improved chemical descriptors that account for the atropselective binding of PCBs to biological macromolecules are, therefore, needed to predict the atropselective partitioning of PCBs in biological systems.
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Affiliation(s)
- Chun-Yun Zhang
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Susanne Flor
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Gabriele Ludewig
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, The University of Iowa, Iowa City, Iowa 52242, United States
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19
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Cano-Sancho G, Casas M. Interactions between environmental pollutants and dietary nutrients: current evidence and implications in epidemiological research. J Epidemiol Community Health 2020; 75:108-113. [PMID: 33023970 DOI: 10.1136/jech-2020-213789] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 08/18/2020] [Accepted: 09/23/2020] [Indexed: 11/04/2022]
Abstract
Environmental pollutants and nutrients may be present in the same foodstuffs or dietary patterns; share internal mechanisms of transport, metabolism and cellular uptake; or target the same molecular signalling pathways and biological functions. Lipophilic pollutants and nutrients, like dioxins and polyunsaturated fatty acids, may often converge at all aforementioned levels and thus the interactions become more likely. Despite this fact, the topic seems overlooked in mainstream epidemiological research. In this essay, we illustrate different levels of documented interactions between pollutants and nutrients with experimental, interventional and epidemiological evidence, paying special attention to lipophilic chemicals. We first describe common pollutants and nutrients encountered in diets and the internal lipophilic interface such as adipose tissue and serum lipids. Next, we discuss the preventive effects of nutrients against absorption and the toxic effects of pollutants, as well as the pollutant-induced perturbation of nutrient metabolism. Finally, we discuss the implications of nutrient-pollutant interactions in epidemiology, providing some examples of negative confounding, modification effect and statistical interactions reported for different outcomes including fetal growth, diabetes and cancer. The evidence discussed in this essay supports that the health impacts of chemicals have likely been underestimated due to the high risk of residual and coexposure confounding in diseases where interactions between pollutants and nutrients may occur.
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Affiliation(s)
| | - Maribel Casas
- ISGlobal, Barcelona, Spain.,Pompeu Fabra University, Barcelona, Spain.,Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Madrid, Spain
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20
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Luo C, Hu B, Wang S, Wang Y, Zhao Z, Wang Y, Li J, Zhang G. Distribution and Chiral Signatures of Polychlorinated Biphenyls (PCBs) in Soils and Vegetables around an e-Waste Recycling Site. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:10542-10549. [PMID: 32916050 DOI: 10.1021/acs.jafc.0c00479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The distribution and composition of polychlorinated biphenyls (PCBs) within soil-plant systems around a notorious e-waste recycling site were investigated. The average total PCB concentrations in rhizospheric soils (RSs) and nonrhizospheric soils (NRSs) were 2160 and 1270 pg g-1 dry weight (DW), respectively. PCBs were more enriched in RS than NRS for most vegetable species. PCB accumulation in plant tissues varied greatly among plant cultivars, ranging from 4020 to 14 500 pg g-1 DW in shoots and from 471 to 24 400 pg g-1 DW in roots. The compositions of PCBs in soil and plants showed that hexa- and hepta-chlorinated PCBs were preferentially accumulated in soils, while tri- and tetra-PCBs were abundant in plant tissues. These results indicated that low-chlorinated PCBs might be prone to accumulation and transfer within plants, which was confirmed by the relationship between the root concentration factor and octanol-water coefficient. The first eluting enantiomers of PCB 84 and PCB 95 were preferentially transferred between the soil and plants, while the stereoselectivity of PCB 136 varied among plant species. A significant difference in enantiomeric fractionation of PCB 84 between the soil and roots indicated that enantiomeric enhancement of PCB 84 occurred during its translocation from soil to root, whereas no such difference was observed in these chiral PCBs during their translocation from the root to the shoot.
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Affiliation(s)
- Chunling Luo
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- Joint Institute for Environmental Research and Education, South China Agricultural University, Guangzhou 510642, China
| | - Beibei Hu
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shaorui Wang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Yan Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Zhen Zhao
- College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai 201306, China
| | - Yujie Wang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510640, China
| | - Jun Li
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Gan Zhang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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21
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Huang C, Zeng Y, Luo X, Ren Z, Lu Q, Tian Y, Gao S, Wang S, Harrad S, Mai B. Tracing the sources and microbial degradation of PCBs in field sediments by a multiple-line-of-evidence approach including compound-specific stable isotope analysis. WATER RESEARCH 2020; 182:115977. [PMID: 32619684 DOI: 10.1016/j.watres.2020.115977] [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: 01/21/2020] [Revised: 04/29/2020] [Accepted: 05/23/2020] [Indexed: 06/11/2023]
Abstract
Comprehensive monitoring is crucial for tracing micropollutants in the natural environment. To better evaluate the sources and natural attenuation of polychlorinated biphenyls (PCBs), three composite sediment cores were sampled from a closed pond near e-waste recycling plants, and a multiple-line-of-evidence approach (MLEA) including quantification, enantiomer analysis, microbial community profiling, and compound-specific isotope analysis (CSIA) was used to investigate the fate of PCBs in sediment cores. The difference in the maximum PCB concentrations and associated depths between sites 1/2 and 3 and the corresponding significant (p < 0.01) difference in δ13C values strongly indicated two different PCB inputs at sites 1/2 and 3. A significant (p < 0.01) negative correlation between the variation in chlorine per biphenyl (CPB) and Log the abundance of Dehalococcoides/total molar concentration of PCBs (Log Dhc/TPCB) along the cores suggested that different degrees of PCB degradation occurred and that Dehalococcoides likely participated in PCB degradation in these sediments. Nonracemic compositions and pronounced stable carbon isotope fractionation (Δδ13C > 1‰) of PCB congeners were observed, confirming that in situ degradation occurred in the sediment cores. The progressive enrichment in 13C with increasing core depth suggested strengthened microbial degradation of the residual congener pools. The results of this study suggested that MLEA analysis of PCBs can provide reliable information to better monitor the sources and fate of these compounds in the environment.
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Affiliation(s)
- Chenchen Huang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yanhong Zeng
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
| | - Xiaojun Luo
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Zihe Ren
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Qihong Lu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China
| | - Yankuan Tian
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Shutao Gao
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Shanquan Wang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, China
| | - Stuart Harrad
- School of Geography, Earth & Environmental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Bixian Mai
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
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22
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Meng HJ, Tang B, Zheng J, Ma SX, Cai FS, Zhuang X, Wang JL, Yu YJ. Levels and sources of PBDEs and PCBs in human nails from e-waste, urban, and rural areas in South China. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2020; 22:1710-1717. [PMID: 32667371 DOI: 10.1039/d0em00221f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Human nails have been increasingly used as a biomarker for human exposure to persistent organic pollutants (POPs). In the present study, the fingernails of e-waste-dismantling workers from Longtang town, Qingyuan city, rural residents from Shijiao town, Qingyuan city, and urban residents from Guangzhou city, respectively, were collected from South China to monitor the human burdens of polybrominated diphenyl ether (PBDEs) and polychlorinated biphenyl (PCBs). The median concentrations of in the nails of the e-waste-dismantling workers, and urban and rural residents were 412, 129, and 82.1 ng g-1, respectively, and the median concentrations of were 108, 8.4, and 22.1 ng g-1, respectively. The levels of PCBs and PBDEs in the nails of e-waste-dismantling workers were significantly higher as compared to those for urban and rural residents (p < 0.05), implying the continuous and greater exposure to these chemicals in the e-waste recycling areas. BDE 209 (92-98%) was the major congener of PBDEs and CB 52 (26-51%) was the main congener of PCB in nail samples. However, no significant gender difference was observed for PBDE and PCB levels in nails from all three investigated areas, and no significant correlation was found between their levels and the age of the participants. The enantiomer fractions (EFs) of CBs 95 and 132 indicated that the external sources (e.g. dust and/or air) were the primary sources for CBs 95 and 132 in human nails from the e-waste area, while the contribution from the internal sources (e.g. serum) could be in a small percentage. The results of this study indicate that human nails can be used as a proper indicator of human exposure to PCBs and PBDEs, and further studies are needed by a comprehensive investigation of the relationships between the PCB and PBDE levels in the nails and serum and/or other internal tissues.
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Affiliation(s)
- Hua-Jun Meng
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510655, P. R. China.
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23
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Liu J, Tan Y, Song E, Song Y. A Critical Review of Polychlorinated Biphenyls Metabolism, Metabolites, and Their Correlation with Oxidative Stress. Chem Res Toxicol 2020; 33:2022-2042. [DOI: 10.1021/acs.chemrestox.0c00078] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Jing Liu
- College of Eco-Environmental Engineering, Guizhou Minzu University, Guiyang 550025, People’s Republic of China
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People’s Republic of China
| | - Ya Tan
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People’s Republic of China
| | - Erqun Song
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People’s Republic of China
| | - Yang Song
- College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, People’s Republic of China
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24
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Liao G, Song X, Wang X, Zhang W, Zhang L, Qiu J, Hou R. Cytotoxicity of 2,2',3,5',6-Pentachlorobiphenyl (PCB95) and its metabolites in the chicken embryo liver cells of laying hens. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 194:110338. [PMID: 32135376 DOI: 10.1016/j.ecoenv.2020.110338] [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: 12/06/2019] [Revised: 02/10/2020] [Accepted: 02/13/2020] [Indexed: 06/10/2023]
Abstract
2,2',3,5',6-Pentachlorobiphenyl (PCB95) is known as a persistent pollutant that was found in eggs in China. PCB 95 can be metabolized into OH-PCB95 and MeO-PCB95 in liver microsomes. However, the toxicity and its mechanism of PCB95 or its metabolites have been little studied on laying hens. Herein, chicken embryo liver cells of laying hens were selected and treated with different levels of PCB95 and its two metabolites, and the EC50 of PCB95, OH-PCB95, MeO-PCB95 was 80.85, 4.81 and 107.04 μg/mL respectively, indicating that OH-PCB95 is much more cytotoxic than PCB95 or MeO-PCB95. Targeted metabolomics was further used to study the effects of the parent compound and its metabolites on cell metabolism. The results showed that four primary types of glycerophospholipids were down-regulated after exposure to PCB95 and its metabolites, especially PE and PS (60% more than the control for PCB95, 40% for OH-PCB95, and less than 40% for MeO-PCB95). KEGG pathway analysis based on amino acid metabolism showed that PCB95 may mainly interfere with the amino acids involved in immune regulation (phenylalanine and tyrosine), and OH-PCB95 may be associated with genetic disoders (cysteine, methionine and purine metabolism). However, the metabolic pathways induced by MeO-PCB95 are quite different from those induced by PCB95 and OH-PCB95, affecting mainly D-glutamine and D-glutamate metabolism, alanine and glutamate metabolism, and arginine and proline metabolism; these pathways mainly regulate the elimination of excess purines and are involved in the synthesis of the amino acids required by cells. These results showed that OH-PCB95 has the highest toxicity on chicken embryo liver cells and MeO-PCB95 could be a detoxification product of PCB95 and OH-PCB95. This study contributes to the understanding of the different effects of PCB95 and its metabolites on cellular metabolism, and the data are helpful in evaluating the hepatotoxic effects of these compounds.
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Affiliation(s)
- Guangqin Liao
- State Key Laboratory of Tea Plant Biology and Utilization, Key Lab of Food Nutrition and Safety, School of Tea and Food Science & Technology, Anhui Agricultural University, Hefei, 230036, China; Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Key Laboratory of Agri-food Quality and Safety, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China
| | - Xiao Song
- Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Key Laboratory of Agri-food Quality and Safety, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China
| | - Xinlu Wang
- Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Key Laboratory of Agri-food Quality and Safety, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China
| | - Wei Zhang
- Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Key Laboratory of Agri-food Quality and Safety, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China
| | - Lin Zhang
- Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Key Laboratory of Agri-food Quality and Safety, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China
| | - Jing Qiu
- Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Key Laboratory of Agri-food Quality and Safety, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China.
| | - Ruyan Hou
- State Key Laboratory of Tea Plant Biology and Utilization, Key Lab of Food Nutrition and Safety, School of Tea and Food Science & Technology, Anhui Agricultural University, Hefei, 230036, China; Institute of Quality Standards & Testing Technology for Agro-Products, Key Laboratory of Agro-product Quality and Safety, Chinese Academy of Agricultural Sciences, Key Laboratory of Agri-food Quality and Safety, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China.
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25
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Dhakal R, Li X, Parkin SR, Lehmler HJ. Synthesis of mono- and dimethoxylated polychlorinated biphenyl derivatives starting from fluoroarene derivatives. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:8905-8925. [PMID: 31893358 PMCID: PMC7098850 DOI: 10.1007/s11356-019-07133-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 11/20/2019] [Indexed: 06/10/2023]
Abstract
Polychlorinated biphenyls (PCBs) are environmental pollutants implicated in a variety of adverse health effects, including cancer and noncancer diseases in animals and humans. PCBs are metabolized to hydroxylated compounds, and some of these PCB metabolites are more toxic than the parent PCBs. Unfortunately, most PCB metabolites needed for toxicological studies are not available from commercial sources. Moreover, it is challenging to synthesize PCB metabolites because starting materials with suitable substitution patterns are not readily available. Here, we report the novel synthesis of a variety of mono- and dimethoxyarene derivatives from commercially available fluoroarenes via nucleophilic aromatic substitution with sodium methoxide. This reaction provided good to excellent yields of the desired methoxylated products. Suzuki coupling of selected mono- and dimethoxy haloarenes with chlorinated phenylboronic acids yielded methoxylated derivatives of PCB 11, 12, 25, 35, and 36 in low to good yields. Crystal structures of 3,3'-dichloro-2,5-dimethoxy-1,1'-biphenyl and 3',5-dichloro-2,3-dimethoxy-1,1'-biphenyl confirmed the substitution pattern of both compounds. This synthesis strategy provides straightforward access to a range of mono- and dimethoxylated PCB derivatives that were not readily accessible previously.
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Affiliation(s)
- Ram Dhakal
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242, USA
| | - Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242, USA
| | - Sean R Parkin
- Department of Chemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242, USA.
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26
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Abstract
3,5-Dichloro-3',4'-dimethoxybiphenyl, C14H12Cl2O2, is a dihydroxylated metabolite of 3,4-dichlorobiphenyl (PCB 14). The title compound displays π-π stacking interactions between inversion related chlorinated benzene rings, with an inter-planar stacking distance of 3.3695 (17) Å. The dihedral angle between the two benzene rings was 42.49 (6)°. The methoxy groups on the non-chlorinated ring lie essentially in the plane of the benzene ring, with dihedral angles of 4.0 (2)° and -2.07 (19)°.
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Affiliation(s)
- Ram Dhakal
- The University of Iowa, Department of Occupational and Environmental Health, University of Iowa Research Park, Iowa City, IA 52242, USA
| | - Sean Parkin
- Department of Chemistry, University of Kentucky, Lexington, KY 40506, USA
| | - Hans-Joachim Lehmler
- The University of Iowa, Department of Occupational and Environmental Health, University of Iowa Research Park, Iowa City, IA 52242, USA
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27
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Żwierełło W, Maruszewska A, Skórka-Majewicz M, Goschorska M, Baranowska-Bosiacka I, Dec K, Styburski D, Nowakowska A, Gutowska I. The influence of polyphenols on metabolic disorders caused by compounds released from plastics - Review. CHEMOSPHERE 2020; 240:124901. [PMID: 31563713 DOI: 10.1016/j.chemosphere.2019.124901] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 09/06/2019] [Accepted: 09/17/2019] [Indexed: 06/10/2023]
Abstract
Persistent organic pollutants (POPs) released from plastics into water, soil and air are significant environmental and health problem. Continuous exposure of humans to these substances results not only from the slow biodegradation of plastics but also from their ubiquitous use as industrial materials and everyday products. Exposure to POPs may lead to neurodegenerative disorders, induce inflammation, hepatotoxicity, nephrotoxicity, insulin resistance, allergies, metabolic diseases, and carcinogenesis. This has spurred an increasing intense search for natural compounds with protective effects against the harmful components of plastics. In this paper, we discuss the current state of knowledge concerning the protective functions of polyphenols against the toxic effects of POPs: acrylonitrile, polychlorinated biphenyls, dioxins, phthalates and bisphenol A. We review in detail papers from the last two decades, analyzing POPs in terms of their sources of exposure and demonstrate how polyphenols may be used to counteract the harmful environmental effects of POPs. The protective effect of polyphenols results from their impact on the level and activity of the components of the antioxidant system, enzymes involved in the elimination of xenobiotics, and as a consequence - on the level of reactive oxygen species (ROS). Polyphenols present in daily diet may play a protective role against the harmful effects of POPs derived from plastics, and this interaction is related, among others, to the antioxidant properties of these compounds. To our knowledge, this is the first extensive review of in vitro and in vivo studies concerning the molecular mechanisms of interactions between selected environmental toxins and polyphenols.
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Affiliation(s)
- Wojciech Żwierełło
- Department of Human Nutrition and Metabolomics, Pomeranian Medical University in Szczecin, 24 Broniewskiego St., 71-460, Szczecin, Poland
| | - Agnieszka Maruszewska
- Department of Biochemistry, Faculty of Biology, University of Szczecin, 3c Felczaka St., 71-412, Szczecin, Poland
| | - Marta Skórka-Majewicz
- Department of Human Nutrition and Metabolomics, Pomeranian Medical University in Szczecin, 24 Broniewskiego St., 71-460, Szczecin, Poland
| | - Marta Goschorska
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, 72 Powst. Wlkp. St., 70-111, Szczecin, Poland
| | - Irena Baranowska-Bosiacka
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, 72 Powst. Wlkp. St., 70-111, Szczecin, Poland
| | - Karolina Dec
- Department of Human Nutrition and Metabolomics, Pomeranian Medical University in Szczecin, 24 Broniewskiego St., 71-460, Szczecin, Poland
| | - Daniel Styburski
- Department of Human Nutrition and Metabolomics, Pomeranian Medical University in Szczecin, 24 Broniewskiego St., 71-460, Szczecin, Poland
| | - Anna Nowakowska
- Centre for Human Structural and Functional Research, Faculty of Physical Education and Health Promotion, University of Szczecin, 17C Narutowicza St., 70-240, Szczecin, Poland
| | - Izabela Gutowska
- Department of Medical Chemistry, Pomeranian Medical University in Szczecin, 72 Powst. Wlkp. St., 70-111, Szczecin, Poland.
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28
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Dhakal R, Parkin S, Lehmler HJ. 3-(3,5-Dichlorophenyl)benzene-1,2-diol. IUCRDATA 2019; 4:191202. [PMID: 34708161 PMCID: PMC8547764 DOI: 10.1107/s2414314619012021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 08/30/2019] [Indexed: 11/10/2022] Open
Abstract
The title structure [systematic name: 4-(3,5-dichlorophenyl)benzene-1,2-diol], C12H8Cl2O2, is a putative metabolite of 3,5-dichlorobiphenyl (PCB 14). The dihedral angle between the two benzene rings of the title compounds is 58.86 (4)°. In the crystal, it displays intra and intermolecular O-H···O hydrogen bonding and intermolecular O-H···Cl hydrogen···chlorine interactions.
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Affiliation(s)
- Ram Dhakal
- The University of Iowa, Department of Occupational and Environmental Health, University of Iowa Research Park, Iowa City, IA 52242, USA
| | - Sean Parkin
- Department of Chemistry, University of Kentucky, Chemistry-Physics Bldg, Lexington, KY 40506-0055, USA
| | - Hans-Joachim Lehmler
- The University of Iowa, Department of Occupational and Environmental Health, University of Iowa Research Park, Iowa City, IA 52242, USA
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29
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Wu X, Zhai G, Schnoor JL, Lehmler HJ. Atropselective Disposition of 2,2',3,4',6-Pentachlorobiphenyl (PCB 91) and Identification of Its Metabolites in Mice with Liver-Specific Deletion of Cytochrome P450 Reductase. Chem Res Toxicol 2019; 33:1328-1338. [PMID: 31403789 DOI: 10.1021/acs.chemrestox.9b00255] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hepatic cytochrome P450 enzymes metabolize chiral polychlorinated biphenyls (PCBs) to hydroxylated metabolites (OH-PCBs). Animal models with impaired metabolism of PCBs are one approach to study how the atropselective oxidation of PCBs to OH-PCBs contributes to toxic outcomes, such as neurodevelopmental disorders, following PCB exposure. We investigated the disposition of PCB 91, a para-substituted PCB congener, in mice with a liver-specific deletion of the cytochrome P450 reductase (cpr) gene (KO mice). KO mice and wild-type (WT) mice were exposed orally to racemic PCB 91 (30 mg/kg b.w.). Levels and enantiomeric fractions of PCB 91 and its hydroxylated metabolites were determined in tissues 3 days after PCB exposure and in excreta on days 1-3 after PCB exposure. PCB 91, but not OH-PCB levels were higher in KO compared to WT mice. The elevated fat and protein content in the liver of KO mice resulted in the hepatic accumulation of PCB 91. OH-PCBs were detected in blood, liver, and excreta samples of KO and WT mice. 2,2',3,4',6-Pentachlorobiphenyl-5-ol (5-91) was the major metabolite. A considerable percent of the total PCB 91 dose (%TD) was excreted with the feces as 5-91 (23%TD and 31%TD in KO and WT mice, respectively). We tentatively identified glucuronide and sulfate metabolites present in urine samples. The PCB 91 atropisomer eluting first on the chiral column (E1-PCB 91) displayed genotype-dependent atropisomeric enrichment, with a more pronounced atropisomeric enrichment observed in WT compared to KO mice. E1-atropisomers of 5-91 and 2,2',3,4',6-pentachlorobiphenyl-4-ol (4-91) were enriched in blood and liver, irrespective of the genotype; however, the extent of the enrichment of E1-5-91 was genotype dependent. These differences in atropselective disposition are consistent with slower metabolism of PCB 91 in KO compared to WT mice and the accumulation of the parent PCB in the fatty liver of KO mice.
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30
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Uwimana E, Cagle B, Yeung C, Li X, Patterson EV, Doorn JA, Lehmler HJ. Atropselective Oxidation of 2,2',3,3',4,6'-Hexachlorobiphenyl (PCB 132) to Hydroxylated Metabolites by Human Liver Microsomes and Its Implications for PCB 132 Neurotoxicity. Toxicol Sci 2019; 171:406-420. [PMID: 31268529 PMCID: PMC6760323 DOI: 10.1093/toxsci/kfz150] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 06/18/2019] [Accepted: 06/18/2019] [Indexed: 02/05/2023] Open
Abstract
Polychlorinated biphenyls (PCBs) have been associated with neurodevelopmental disorders. Several neurotoxic congeners display axial chirality and atropselectively affect cellular targets implicated in PCB neurotoxicity. Only limited information is available regarding the atropselective metabolism of these congeners in humans and their atropselective effects on neurotoxic outcomes. Here we investigate the hypothesis that the oxidation of 2,2',3,3',4,6'-hexachlorobiphenyl (PCB 132) by human liver microsomes (HLMs) and their effects on dopaminergic cells in culture are atropselective. Racemic PCB 132 was incubated with pooled or single donor HLMs, and levels and enantiomeric fractions of PCB 132 and its metabolites were determined gas chromatographically. The major metabolite was either 2,2',3,4,4',6'-hexachlorobiphenyl-3'-ol (3'-140), a 1,2-shift product, or 2,2',3,3',4,6'-hexachlorobiphenyl-5'-ol (5'-132). The PCB 132 metabolite profiles displayed inter-individual differences and depended on the PCB 132 atropisomer. Computational studies suggested that 3'-140 is formed via a 3,4-arene oxide intermediate. The second eluting atropisomer of PCB 132, first eluting atropisomer of 3'-140, and second eluting atropisomer of 5'-132 were enriched in all HLM incubations. Enantiomeric fractions of the PCB 132 metabolites differed only slightly between the single donor HLM preparations investigated. Reactive oxygen species and levels of dopamine and its metabolites were not significantly altered after a 24 h exposure of dopaminergic cells to pure PCB 132 atropisomers. These findings suggest that there are inter-individual differences in the atropselective biotransformation of PCB 132 to its metabolites in humans; however, the resulting atropisomeric enrichment of PCB 132 is unlikely to affect neurotoxic outcomes associated with the endpoints investigated in the study.
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Affiliation(s)
- Eric Uwimana
- Interdisciplinary Graduate Program in Human Toxicology and Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, Iowa
| | - Brianna Cagle
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA, United States
| | - Coby Yeung
- Department of Chemistry, College of Arts and Sciences, Stony Brook University, Stony Brook, New York
| | - Xueshu Li
- Interdisciplinary Graduate Program in Human Toxicology and Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, Iowa
| | - Eric V Patterson
- Department of Chemistry, College of Arts and Sciences, Stony Brook University, Stony Brook, New York
| | - Jonathan A Doorn
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA, United States
| | - Hans-Joachim Lehmler
- Interdisciplinary Graduate Program in Human Toxicology and Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, Iowa
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31
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Daramola O, Cullen J. Identifying absolute configurations of PCB atropisomers by comparison of their experimental specific rotations with their DFT calculated values. CAN J CHEM 2019. [DOI: 10.1139/cjc-2018-0458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nineteen enantiomer pairs of polychlorinated biphenyls (PCBs) with three or four chloro substituents about the central carbon–carbon bond form a stable subclass of compounds whose biological effects vary with their chirality. Optical rotations for this group of PCBs were determined from density functional calculations employing extended atomic orbital gauge invariant basis sets. A comparison of these results with the experimental ones found from the literature for 10 of the pairs enabled the identification of their absolute configurations as analytes in gas chromatography studies.
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Affiliation(s)
- Oluwadamilola Daramola
- Department of Chemistry, University of Manitoba, 144 Dysart Road, Winnipeg, MB R3T 2N2, Canada
- Department of Chemistry, University of Manitoba, 144 Dysart Road, Winnipeg, MB R3T 2N2, Canada
| | - John Cullen
- Department of Chemistry, University of Manitoba, 144 Dysart Road, Winnipeg, MB R3T 2N2, Canada
- Department of Chemistry, University of Manitoba, 144 Dysart Road, Winnipeg, MB R3T 2N2, Canada
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Wang H, Xia X, Liu R, Wang Z, Zhai Y, Lin H, Wen W, Li Y, Wang D, Yang Z, Muir DCG, Crittenden JC. Dietary Uptake Patterns Affect Bioaccumulation and Biomagnification of Hydrophobic Organic Compounds in Fish. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:4274-4284. [PMID: 30884228 DOI: 10.1021/acs.est.9b00106] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Biomagnification of hydrophobic organic compounds (HOCs) increases the eco-environmental risks they pose. Here, we gained mechanistic insights into biomagnification of deuterated polycyclic aromatic hydrocarbons (PAHs- d10) in zebrafish with carefully controlled water (ng L-1) by a passive dosing method and dietary exposures using pre-exposed Daphnia magna and fish food. A new bioaccumulation kinetic model for fish was established to take into account discrete dietary uptake, while the frequently used model regards dietary uptake as a continuous process. We found that when freely dissolved concentrations of the PAHs- d10 were constant in water, the intake amount of the PAHs- d10 played an important role in affecting their steady-state concentrations in zebrafish, and there was a peak concentration in zebrafish after each dietary uptake. Moreover, considering the randomness of predation, the Monte Carlo simulation results showed that the probabilities of biomagnification of the PAHs- d10 in zebrafish increased with their dietary uptake amount and frequency. This study indicates that in addition to the well-known lipid-water partitioning, the bioaccumulation of HOCs in fish is also a discontinuous kinetic process caused by the fluctuation of HOC concentration in the gastrointestinal tract as a result of the discrete food ingestion. The discontinuity and randomness of dietary uptake can partly explain the differences among aquatic ecosystems with respect to biomagnification for species at similar trophic levels and provides new insight for future analysis of experimental and field bioaccumulation data for fish.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Derek C G Muir
- Aquatic Contaminants Research Division , Environment and Climate Change Canada , Burlington , Ontario L7S 1A1 Canada
- School of Environment , Jinan University , Guangzhou , 510632 , China
| | - John C Crittenden
- Brook Byers Institute for Sustainable Systems and School of Civil and Environmental Engineering , Georgia Institute of Technology , 828 West Peachtree Street , Atlanta , Georgia 30332 , United States
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Lu Q, Qiu L, Yu L, Zhang S, de Toledo RA, Shim H, Wang S. Microbial transformation of chiral organohalides: Distribution, microorganisms and mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2019; 368:849-861. [PMID: 30772625 DOI: 10.1016/j.jhazmat.2019.01.103] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 01/29/2019] [Accepted: 01/30/2019] [Indexed: 05/27/2023]
Abstract
Chiral organohalides including dichlorodiphenyltrichloroethane (DDT), Hexabromocyclododecane (HBCD) and polychlorinated biphenyls (PCBs) raise a significant concern in the environmental occurrence, fate and ecotoxicology due to their enantioselective biological effects. This review provides a state-of-the-art overview on enantioselective microbial transformation of the chiral organohalides. We firstly summarized worldwide field assessments of chiral organohalides in a variety of environmental matrices, which suggested the pivotal role of microorganisms in enantioselective transformation of chiral organohalides. Then, laboratory studies provided experimental evidences to further link enantioselective attenuation of chiral organohalides to specific functional microorganisms and enzymes, revealing mechanistic insights into the enantioselective microbial transformation processes. Particularly, a few amino acid residues in the functional enzymes could play a key role in mediating the enantioselectivity at the molecular level. Finally, major challenges and further developments toward an in-depth understanding of the enantioselective microbial transformation of chiral organohalides are identified and discussed.
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Affiliation(s)
- Qihong Lu
- School of Environmental Science and Engineering, Sun Yat-Sen University, 510275 Guangzhou, China; Environmental Microbiome Research Center, Sun Yat-Sen University, 510275 Guangzhou, China
| | - Lan Qiu
- School of Environmental Science and Engineering, Sun Yat-Sen University, 510275 Guangzhou, China
| | - Ling Yu
- School of Environmental Science and Engineering, Sun Yat-Sen University, 510275 Guangzhou, China; Environmental Microbiome Research Center, Sun Yat-Sen University, 510275 Guangzhou, China
| | - Shangwei Zhang
- UFZ Department of Ecological Chemistry, Helmholtz Centre for Environmental Research, Permoserstraße 15, 04318 Leipzig, Germany
| | - Renata Alves de Toledo
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, 999078 Macau SAR, China
| | - Hojae Shim
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, 999078 Macau SAR, China
| | - Shanquan Wang
- School of Environmental Science and Engineering, Sun Yat-Sen University, 510275 Guangzhou, China; Environmental Microbiome Research Center, Sun Yat-Sen University, 510275 Guangzhou, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, 510275 Guangzhou, China.
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Li X, Wu X, Kelly KM, Veng-Pedersen P, Lehmler HJ. Toxicokinetics of Chiral PCB 136 and Its Hydroxylated Metabolites in Mice with a Liver-Specific Deletion of Cytochrome P450 Reductase. Chem Res Toxicol 2019; 32:727-736. [PMID: 30729780 DOI: 10.1021/acs.chemrestox.8b00389] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Exposure to polychlorinated biphenyls (PCBs) has been implicated in adverse human health effects, including developmental neurotoxicity. Several neurotoxic PCBs are chiral and undergo atropisomeric enrichment in vivo due to atropselective metabolism by cytochrome P450 enzymes. Here we study how the liver-specific deletion of the cytochrome P450 reductase ( cpr) gene alters the toxicokinetics of 2,2',3,3',6,6'-hexachlorobiphenyl (PCB 136) in mice. Male and female mice with a liver-specific deletion of cpr (KO) and congenic wild-type (WT) mice were exposed to a single oral dose of racemic PCB 136 (6.63 mg/kg). Levels and chiral signatures of PCB 136 and its hydroxylated metabolites were determined 1-48 h after PCB exposure in whole blood. Blood levels of PCB 136 were typically higher in M-WT compared to F-WT mice. At the later time points, F-KO mice had significantly higher PCB 136 levels than F-WT mice. 2,2',3',4,6,6'-Hexachlorobiphenyl-3-ol (3-150), 2,2',3,3',6,6'-hexachlorobiphenyl-4-ol (4-136), 2,2',3,3',6,6'-hexachlorobiphenyl-5-ol (5-136), and 4,5-dihydroxy-2,2',3,3',6,6'-hexachlorobiphenyl (4,5-136) were detected in blood, with 5-136 and 4-136 being major metabolites. At later time points, the sum of HO-PCB (∑HO-PCB) levels exceeded PCB 136 levels in the blood; however, higher ∑HO-PCB than PCB 136 levels were observed later in KO than WT mice. PCB 136 and its major metabolites displayed atropisomeric enrichment in a manner that depended on the time point, sex, and genotype. Toxicokinetic analysis revealed sex and genotype-dependent differences in toxicokinetic parameters for PCB 136 atropisomers and its metabolites. The results suggest that mice with a liver-specific deletion of the cpr gene can potentially be used to assess how an altered metabolism of neurotoxic PCB congeners affects neurotoxic outcomes following exposure of the offspring to PCBs via the maternal diet.
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Affiliation(s)
- Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health , University of Iowa , Iowa City , Iowa 52242 , United States
| | - Xianai Wu
- Department of Occupational and Environmental Health, College of Public Health , University of Iowa , Iowa City , Iowa 52242 , United States
| | - Kevin M Kelly
- Department of Occupational and Environmental Health, College of Public Health , University of Iowa , Iowa City , Iowa 52242 , United States
| | - Peter Veng-Pedersen
- College of Pharmacy , University of Iowa , Iowa City , Iowa 52242 , United States
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health , University of Iowa , Iowa City , Iowa 52242 , United States
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Uwimana E, Ruiz P, Li X, Lehmler HJ. Human CYP2A6, CYP2B6, AND CYP2E1 Atropselectively Metabolize Polychlorinated Biphenyls to Hydroxylated Metabolites. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:2114-2123. [PMID: 30576102 PMCID: PMC6380921 DOI: 10.1021/acs.est.8b05250] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Exposure to chiral polychlorinated biphenyls (PCBs) has been associated with neurodevelopmental disorders. Their hydroxylated metabolites (OH-PCBs) are also potentially toxic to the developing human brain; however, the formation of OH-PCBs by human cytochrome P450 (P450) isoforms is poorly investigated. To address this knowledge gap, we investigated the atropselective biotransformation of 2,2',3,4',6-pentachlorobiphenyl (PCB 91), 2,2',3,5',6-pentachlorobiphenyl (PCB 95), 2,2',3,3',4,6'-hexachlorobiphenyl (PCB 132), and 2,2',3,3',6,6'-hexachlorobiphenyl (PCB 136) by different human P450 isoforms. In silico predictions with ADMET Predictor and MetaDrug software suggested a role of CYP1A2, CYP2A6, CYP2B6, CYP2E1, and CYP3A4 in the metabolism of chiral PCBs. Metabolism studies with recombinant human enzymes demonstrated that CYP2A6 and CYP2B6 oxidized PCB 91 and PCB 132 in the meta position and that CYP2A6 oxidized PCB 95 and PCB 136 in the para position. CYP2B6 played only a minor role in the metabolism of PCB 95 and PCB 136 and formed meta-hydroxylated metabolites. Traces of para-hydroxylated PCB metabolites were detected in incubations with CYP2E1. No hydroxylated metabolites were present in incubations with CYP1A2 or CYP3A4. Atropselective analysis revealed P450 isoform-dependent and congener-specific atropselective enrichment of OH-PCB metabolites. These findings suggest that CYP2A6 and CYP2B6 play an important role in the oxidation of neurotoxic PCBs to chiral OH-PCBs in humans.
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Affiliation(s)
- Eric Uwimana
- Interdisciplinary Graduate Program in Human Toxicology and Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52242, United States
| | - Patricia Ruiz
- Division of Toxicology and Human Health Sciences, Computational Toxicology and Methods Development Lab, Agency for Toxic Substances and Disease Registry, Atlanta, GA 30333, United States
| | - Xueshu Li
- Interdisciplinary Graduate Program in Human Toxicology and Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52242, United States
| | - Hans-Joachim Lehmler
- Interdisciplinary Graduate Program in Human Toxicology and Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52242, United States
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36
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He Z, Xu Y, Wang W, Liu X. Stereoselective bioaccumulation and elimination of chiral PCBs 95 and 149 in earthworm Eisenia fetida. CHEMOSPHERE 2018; 212:497-503. [PMID: 30153619 DOI: 10.1016/j.chemosphere.2018.08.075] [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: 07/05/2018] [Revised: 08/13/2018] [Accepted: 08/14/2018] [Indexed: 06/08/2023]
Abstract
The chiral signatures and environmental behaviors of chiral polychlorinated biphenyls (PCBs) have been extensively studied. However, information regarding chiral PCBs in invertebrates, especially earthworms, is limited. This study aimed to investigate the stereoselective bioaccumulation, elimination, and biotransformation of chiral PCBs 95 and 149 in an earthworm-soil system. Preferential enrichment of (+)-atropisomers and elimination of (-)-atropisomers were observed, for both PCBs 95 and 149, during the uptake and elimination phases, respectively, leading to higher enantiomer fractions (EFs). A significant linear correlation between the total concentrations of chiral PCBs and EF values was found in earthworms. The EF values increased with the increase in exposure time and further increased during the elimination phase, indicating the biotransformation of chiral PCBs. Hydroxylated metabolites of PCB 95 were found in earthworms for the first time, thus verifying the ability of earthworms to metabolize chiral PCBs. However, no methylsulfonyl metabolites were observed for PCBs 95 and 149. These findings might be helpful for understanding the biological processes of chiral PCBs in species at lower trophic levels.
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Affiliation(s)
- Zeying He
- Key Laboratory for Environmental Factors Control of Agro-product Quality Safety, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, PR China
| | - Yaping Xu
- Key Laboratory for Environmental Factors Control of Agro-product Quality Safety, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, PR China
| | - Wenwen Wang
- Agilent Technologies (China) Company, Ltd., Beijing 100102, PR China
| | - Xiaowei Liu
- Key Laboratory for Environmental Factors Control of Agro-product Quality Safety, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191, PR China.
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Kania-Korwel I, Lukasiewicz T, Barnhart CD, Stamou M, Chung H, Kelly KM, Bandiera S, Lein PJ, Lehmler HJ. Editor's Highlight: Congener-Specific Disposition of Chiral Polychlorinated Biphenyls in Lactating Mice and Their Offspring: Implications for PCB Developmental Neurotoxicity. Toxicol Sci 2018; 158:101-115. [PMID: 28431184 DOI: 10.1093/toxsci/kfx071] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Chiral polychlorinated biphenyl (PCB) congeners have been implicated by laboratory and epidemiological studies in PCB developmental neurotoxicity. These congeners are metabolized by cytochrome P450 (P450) enzymes to potentially neurotoxic hydroxylated metabolites (OH-PCBs). The present study explores the enantioselective disposition and toxicity of 2 environmentally relevant, neurotoxic PCB congeners and their OH-PCB metabolites in lactating mice and their offspring following dietary exposure of the dam. Female C57BL/6N mice (8-weeks old) were fed daily, beginning 2 weeks prior to conception and continuing throughout gestation and lactation, with 3.1 µmol/kg bw/d of racemic 2,2',3,5',6-pentachlorobiphenyl (PCB 95) or 2,2',3,3',6,6'-hexachlorobiphenyl (PCB 136) in peanut butter; controls received vehicle (peanut oil) in peanut butter. PCB 95 levels were higher than PCB 136 levels in both dams and pups, consistent with the more rapid metabolism of PCB 136 compared with PCB 95. In pups and dams, both congeners were enriched for the enantiomer eluting second on enantioselective gas chromatography columns. OH-PCB profiles in lactating mice and their offspring were complex and varied according to congener, tissue and age. Developmental exposure to PCB 95 versus PCB 136 differentially affected the expression of P450 enzymes as well as neural plasticity (arc and ppp1r9b) and thyroid hormone-responsive genes (nrgn and mbp). The results suggest that the enantioselective metabolism of PCBs to OH-PCBs may influence neurotoxic outcomes following developmental exposures, a hypothesis that warrants further investigation.
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Affiliation(s)
- Izabela Kania-Korwel
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa
| | - Tracy Lukasiewicz
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa
| | - Christopher D Barnhart
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, California
| | - Marianna Stamou
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, California
| | - Haeun Chung
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Kevin M Kelly
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa
| | - Stelvio Bandiera
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Pamela J Lein
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, California
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa
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He Z, Wang Y, Zhang Y, Cheng H, Liu X. Stereoselective bioaccumulation of chiral PCB 91 in earthworm and its metabolomic and lipidomic responses. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 238:421-430. [PMID: 29587213 DOI: 10.1016/j.envpol.2018.03.060] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 02/03/2018] [Accepted: 03/16/2018] [Indexed: 06/08/2023]
Abstract
Stereoselective bioaccumulation, elimination, metabolomic and lipidomic responses of earthworm Eisenia fetida exposed to chiral polychlorinated biphenyl (PCB) 91 in an earthworm-soil system were investigated. Preferential bioaccumulation of (-)-PCB 91 and elimination of (+)-PCB 91 were observed following 50 and 500 μg/kgdwt exposures. Enantiomer fraction (EF) values decreased over time during the uptake and elimination periods. Metabolomics and lipidomics techniques based on ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) revealed significant changes in 108 metabolites after earthworms exposure to (+)-, (-)-, and (±)-PCB 91, compared to control groups. Forty two of these metabolites were identified as amino acids, nucleosides, fatty acids, dicarboxylic acids, vitamins or others. Lysophospholipids including six lysophosphatidylcholines (LPC), six lysophosphatidylethanolamine (LPE), eight lysophosphatidylinositol (LPI) and five lysophosphatidylserine (LPS) were also differentially expressed between exposure and control groups. Alterations in the levels of metabolites and lipids indicated stereoselective effects of chiral PCB 91 on earthworm amino acid, energy, and nucleotide metabolism, neurodevelopment and gene expression. Overall, the effects of (+)-PCB 91 were more pronounced than that of (-)- and (±)-PCB 91.
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Affiliation(s)
- Zeying He
- Key Laboratory for Environmental Factors Control of Agro-product Quality Safety, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin, 300191, PR China
| | - Yuehua Wang
- Key Laboratory for Environmental Factors Control of Agro-product Quality Safety, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin, 300191, PR China
| | - Yanwei Zhang
- Key Laboratory for Environmental Factors Control of Agro-product Quality Safety, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin, 300191, PR China
| | - Haiyan Cheng
- SCIEX, Analytical Instrument Trading Co., Ltd, Beijing, 100015, PR China
| | - Xiaowei Liu
- Key Laboratory for Environmental Factors Control of Agro-product Quality Safety, Ministry of Agriculture, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin, 300191, PR China.
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Nagayoshi H, Kakimoto K, Konishi Y, Kajimura K, Nakano T. Determination of the human cytochrome P450 monooxygenase catalyzing the enantioselective oxidation of 2,2',3,5',6-pentachlorobiphenyl (PCB 95) and 2,2',3,4,4',5',6-heptachlorobiphenyl (PCB 183). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:16420-16426. [PMID: 29043584 DOI: 10.1007/s11356-017-0434-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 10/05/2017] [Indexed: 04/16/2023]
Abstract
2,2',3,5',6-Pentachlorobiphenyl (PCB 95) and 2,2',3,4,4',5',6-heptachlorobiphenyl (PCB 183) possess axial chirality and form the aS and aR enantiomers. The enantiomers of these congeners have been reported to accumulate in the human body enantioselectively via unknown mechanisms. In this study, we determined the cytochrome P450 (CYP) monooxygenase responsible for the enantioselective oxidization of PCB 95 and PCB 183, using a recombinant human CYP monooxygenase. We evaluated 13 CYP monooxygenases, namely CYP1A1, CYP1A2, CYP1B1, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2, CYP3A4, CYP3A5, CYP4F2, and aromatase (CYP19), and revealed that CYP2A6 preferably oxidizes aS-PCB 95 enantioselectively; however, it did not oxidize PCB 183. The enantiomer composition was elevated from 0.5 (racemate) to 0.54. In addition, following incubation with CYP2A6, the enantiomer fraction (EF) of PCB 95 demonstrated a time-dependent increase.
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Key Words
- 2,2′,3,4,4′,5′,6-heptachlorobiphenyl
- 2,2′,3,5′,6-pentachlorobiphenyl
- Cytochrome P450 2A6
- Enantiomer
- Enantioselective analysis
- Enantioselective oxidation
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Affiliation(s)
- Haruna Nagayoshi
- Osaka Institute of Public Health, 1-3-69 Nakamichi, Higashinari-ku, Osaka, 537-0025, Japan.
| | - Kensaku Kakimoto
- Osaka Institute of Public Health, 1-3-69 Nakamichi, Higashinari-ku, Osaka, 537-0025, Japan
| | - Yoshimasa Konishi
- Osaka Institute of Public Health, 1-3-69 Nakamichi, Higashinari-ku, Osaka, 537-0025, Japan
| | - Keiji Kajimura
- Osaka Institute of Public Health, 1-3-69 Nakamichi, Higashinari-ku, Osaka, 537-0025, Japan
| | - Takeshi Nakano
- Research Center for Environment Preservation, Osaka University, 2-4 Yamadaoka, Suita, Osaka, 565-0871, Japan
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Li X, Holland EB, Feng W, Zheng J, Dong Y, Pessah IN, Duffel MW, Robertson LW, Lehmler HJ. Authentication of synthetic environmental contaminants and their (bio)transformation products in toxicology: polychlorinated biphenyls as an example. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:16508-16521. [PMID: 29322390 PMCID: PMC6015536 DOI: 10.1007/s11356-017-1162-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 12/26/2017] [Indexed: 04/15/2023]
Abstract
Toxicological studies use "specialty chemicals" and, thus, should assess and report both identity and degree of purity (homogeneity) of the chemicals (or toxicants) under investigation to ensure that other scientists can replicate experimental results. Although detailed reporting criteria for the synthesis and characterization of organic compounds have been established by organic chemistry journals, such criteria are inconsistently applied to the chemicals used in toxicological studies. Biologically active trace impurities may lead to incorrect conclusions about the chemical entity responsible for a biological response, which in turn may confound risk assessment. Based on our experience with the synthesis of PCBs and their metabolites, we herein propose guidelines for the "authentication" of synthetic PCBs and, by extension, other organic toxicants, and provide a checklist for documenting the authentication of toxicants reported in the peer-reviewed literature. The objective is to expand guidelines proposed for different types of biomedical and preclinical studies to include a thorough authentication of specialty chemicals, such as PCBs and their derivatives, with the goal of ensuring transparent and open reporting of scientific results in toxicology and the environmental health sciences.
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Affiliation(s)
- Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, USA
| | - Erika B Holland
- Department of Biological Sciences, California State University of Long Beach, Long Beach, CA, USA
| | - Wei Feng
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Jing Zheng
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Yao Dong
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Isaac N Pessah
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Michael W Duffel
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, The University of Iowa, Iowa City, IA, USA
| | - Larry W Robertson
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, USA.
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41
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Li X, Parkin SR, Lehmler HJ. Absolute configuration of 2,2',3,3',6-pentachlorinatedbiphenyl (PCB 84) atropisomers. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:16402-16410. [PMID: 28537024 PMCID: PMC5823790 DOI: 10.1007/s11356-017-9259-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 05/10/2017] [Indexed: 05/05/2023]
Abstract
Nineteen polychlorinated biphenyl (PCB) congeners, such as 2,2',3,3',6-pentachlorobiphenyl (PCB 84), display axial chirality because they form stable rotational isomers, or atropisomers, that are non-superimposable mirror images of each other. Although chiral PCBs undergo atropselective biotransformation and atropselectively alter biological processes, the absolute structure of only a few PCB atropisomers has been determined experimentally. To help close this knowledge gap, pure PCB 84 atropisomers were obtained by semi-preparative liquid chromatography with two serially connected Nucleodex β-PM columns. The absolute configuration of both atropisomers was determined by X-ray single-crystal diffraction. The PCB 84 atropisomer eluting first and second on the Nucleodex β-PM column correspond to (aR)-(-)-PCB 84 and (aS)-(+)-PCB 84, respectively. Enantioselective gas chromatographic analysis with the β-cyclodextrin-based CP-Chirasil-Dex CB gas chromatography column showed the same elution order as the Nucleodex β-PM column. Based on earlier reports, the atropisomers eluting first and second on the BGB-172 gas chromatography column are (aR)-(-)-PCB 84 and (aS)-(+)-PCB 84, respectively. An inversion of the elution order is observed on the Cyclosil-B gas chromatography and Cellulose-3 liquid chromatography columns. These results advance the interpretation of environmental and human biomonitoring as well as toxicological studies.
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Affiliation(s)
- Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, 52242, USA
| | - Sean R Parkin
- Department of Chemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, 52242, USA.
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Robertson LW, Weber R, Nakano T, Johansson N. PCBs risk evaluation, environmental protection, and management: 50-year research and counting for elimination by 2028. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:16269-16276. [PMID: 29934860 PMCID: PMC6033322 DOI: 10.1007/s11356-018-2467-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 05/31/2018] [Indexed: 05/27/2023]
Affiliation(s)
| | - Roland Weber
- POPs Environmental Consulting, Schwäbisch Gmünd, Germany
| | - Takeshi Nakano
- Osaka University, Research Center for Environmental Preservation, Osaka, Japan
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Megson D, Brown TA, O'Sullivan G, Robson M, Ortiz X, Worsfold PJ, Comber S, Lohan MC, Reiner EJ. Changes to polychlorinated biphenyl (PCB) signatures and enantiomer fractions across different tissue types in Guillemots. MARINE POLLUTION BULLETIN 2018; 131:174-179. [PMID: 29886934 DOI: 10.1016/j.marpolbul.2018.04.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/06/2018] [Accepted: 04/08/2018] [Indexed: 06/08/2023]
Abstract
Two Guillemot carcases were dissected, each providing 12 discrete tissue samples and 3 samples of partially digested food. One hundred and five PCBs from the 209 PCBs determined by GCxGC-ToFMS were detected. The relative proportions of individual PCBs did not vary greatly within tissue types, although the PCB profile from undigested food could be distinguished. Enantiomer fractions (EFs) were determined for CB-95, CB-136 and CB-149 by GC-HRqToFMS. EFs in the partially digested food were near racemic, with high levels of enrichment for E1 CB-95 in the kidneys and liver (EF of 0.80 and 0.84 respectively). This provides some of the clearest evidence to date that fractionation takes place in the organs where metabolic biotransformation and elimination of PCBs occurs. Our findings also confirm the ability of non-lethal sampling techniques, such as collection of small (<1 g) blood samples, to provide PCB signatures that are representative of an individual organism.
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Affiliation(s)
- David Megson
- School of Science and the Environment, Manchester Metropolitan University, Manchester M1 5GD, UK; Biogeochemistry Research Centre, SoGEES, Plymouth University, Plymouth, Devon PL4 8AA, UK.
| | - Thomas A Brown
- Biogeochemistry Research Centre, SoGEES, Plymouth University, Plymouth, Devon PL4 8AA, UK; Marine Ecology and Chemistry, Scottish Association for Marine Science, Oban PA37 1QA, UK
| | - Gwen O'Sullivan
- Department of Earth & Environmental Science, Mount Royal University, 4825 Mount Royal Gate SW, Calgary, Alberta T3E 6K6, Canada
| | - Matthew Robson
- Ontario Ministry of the Environment and Climate Change, 125 Resources Road, Toronto, Ontario M9P 3V6, Canada
| | - Xavier Ortiz
- Ontario Ministry of the Environment and Climate Change, 125 Resources Road, Toronto, Ontario M9P 3V6, Canada
| | - Paul J Worsfold
- Biogeochemistry Research Centre, SoGEES, Plymouth University, Plymouth, Devon PL4 8AA, UK
| | - Sean Comber
- Biogeochemistry Research Centre, SoGEES, Plymouth University, Plymouth, Devon PL4 8AA, UK
| | - Maeve C Lohan
- Biogeochemistry Research Centre, SoGEES, Plymouth University, Plymouth, Devon PL4 8AA, UK
| | - Eric J Reiner
- Ontario Ministry of the Environment and Climate Change, 125 Resources Road, Toronto, Ontario M9P 3V6, Canada
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Pěnčíková K, Brenerová P, Svržková L, Hrubá E, Pálková L, Vondráček J, Lehmler HJ, Machala M. Atropisomers of 2,2',3,3',6,6'-hexachlorobiphenyl (PCB 136) exhibit stereoselective effects on activation of nuclear receptors in vitro. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:16411-16419. [PMID: 29124635 PMCID: PMC5943194 DOI: 10.1007/s11356-017-0683-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 11/02/2017] [Indexed: 04/16/2023]
Abstract
PCB 136 is an environmentally relevant chiral PCB congener, which has been found in vivo to be present in form of rotational isomers (atropisomers). Its atropselective biotransformation or neurotoxic effects linked with sensitization of ryanodine receptor suggest that it might interact also with other intracellular receptors in a stereospecific manner. However, possible atropselective effects of PCB 136 on nuclear receptor transactivation remain unknown. Therefore, in this study, atropselective effects of PCB 136 on nuclear receptors controlling endocrine signaling and/or expression of xenobiotic and steroid hormone catabolism were investigated. PCB136 atropisomers were found to exert differential effects on estrogen receptor (ER) activation; (+)-PCB 136 was estrogenic, while (-)-PCB 136 was antiestrogenic. In contrast, inhibition of androgen receptor (AR) activity was not stereospecific. Both PCB136 stereoisomers induced the constitutive androgen receptor (CAR)-dependent gene expression; however, no significant stereospecificity of PCB 136 atropisomers was observed. PCB136 was a partial inducer of the pregnane X receptor (PXR)-dependent gene expression. Here, (-)-PCB 136 was a significantly more potent inducer of PXR activity than (+)-PCB 136. Taken together, the present results indicate that at least two nuclear receptors participating in endocrine regulation or metabolism, ER and PXR, could be regulated in an atropselective manner by chiral PCB 136. The enantioselective enrichment of PCB atropisomers in animal and human tissues may thus have significant consequences for endocrine-disrupting effects of chiral ortho-substituted PCB congeners.
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Affiliation(s)
- Kateřina Pěnčíková
- Department of Chemistry and Toxicology, Veterinary Research Institute, 62100, Brno, Czech Republic
| | - Petra Brenerová
- Department of Chemistry and Toxicology, Veterinary Research Institute, 62100, Brno, Czech Republic
| | - Lucie Svržková
- Department of Chemistry and Toxicology, Veterinary Research Institute, 62100, Brno, Czech Republic
| | - Eva Hrubá
- Department of Chemistry and Toxicology, Veterinary Research Institute, 62100, Brno, Czech Republic
| | - Lenka Pálková
- Department of Chemistry and Toxicology, Veterinary Research Institute, 62100, Brno, Czech Republic
| | - Jan Vondráček
- Department of Cytokinetics, Institute of Biophysics of the Czech Academy of Sciences, 62165, Brno, Czech Republic
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, University of Iowa, Iowa City, IA, 52242, USA
| | - Miroslav Machala
- Department of Chemistry and Toxicology, Veterinary Research Institute, 62100, Brno, Czech Republic.
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45
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Dhakal K, Gadupudi GS, Lehmler HJ, Ludewig G, Duffel MW, Robertson LW. Sources and toxicities of phenolic polychlorinated biphenyls (OH-PCBs). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:16277-16290. [PMID: 28744683 PMCID: PMC5785587 DOI: 10.1007/s11356-017-9694-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 06/30/2017] [Indexed: 04/16/2023]
Abstract
Polychlorinated biphenyls (PCBs), a group of 209 congeners that differ in the number and position of chlorines on the biphenyl ring, are anthropogenic chemicals that belong to the persistent organic pollutants (POPs). For many years, PCBs have been a topic of interest because of their biomagnification in the food chain and their environmental persistence. PCBs with fewer chlorine atoms, however, are less persistent and more susceptible to metabolic attack, giving rise to chemicals characterized by the addition of one or more hydroxyl groups to the chlorinated biphenyl skeleton, collectively known as hydroxylated PCBs (OH-PCBs). In animals and plants, this biotransformation of PCBs to OH-PCBs is primarily carried out by cytochrome P-450-dependent monooxygenases. One of the reasons for infrequent detection of lower chlorinated PCBs in serum and other biological matrices is their shorter half-lives, and their metabolic transformation, resulting in OH-PCBs or their conjugates, such as sulfates and glucuronides, or macromolecule adducts. Recent biomonitoring studies have reported the presence of OH-PCBs in human serum. The occurrence of OH-PCBs, the size of this group (there are 837 mono-hydroxyl PCBs alone), and their wide spectra of physical characteristics (pKa's and log P's ranging over 5 to 6 orders of magnitude) give rise to a multiplicity of biological effects. Among those are bioactivation to electrophilic metabolites that can form covalent adducts with DNA and other macromolecules, interference with hormonal signaling, inhibition of enzymes that regulate cellular concentrations of active hormones, and interference with the transport of hormones. This new information creates an urgent need for a new perspective on these often overlooked metabolites.
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Affiliation(s)
- Kiran Dhakal
- Interdisciplinary Graduate Program in Human Toxicology, Graduate College, The University of Iowa, Iowa City, IA, USA
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, 100 Oakdale Campus #219 IREH, Iowa City, IA, 52242-5000, USA
| | - Gopi S Gadupudi
- Interdisciplinary Graduate Program in Human Toxicology, Graduate College, The University of Iowa, Iowa City, IA, USA
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, 100 Oakdale Campus #219 IREH, Iowa City, IA, 52242-5000, USA
| | - Hans-Joachim Lehmler
- Interdisciplinary Graduate Program in Human Toxicology, Graduate College, The University of Iowa, Iowa City, IA, USA
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, 100 Oakdale Campus #219 IREH, Iowa City, IA, 52242-5000, USA
| | - Gabriele Ludewig
- Interdisciplinary Graduate Program in Human Toxicology, Graduate College, The University of Iowa, Iowa City, IA, USA
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, 100 Oakdale Campus #219 IREH, Iowa City, IA, 52242-5000, USA
| | - Michael W Duffel
- Interdisciplinary Graduate Program in Human Toxicology, Graduate College, The University of Iowa, Iowa City, IA, USA
- Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, The University of Iowa, Iowa City, IA, USA
| | - Larry W Robertson
- Interdisciplinary Graduate Program in Human Toxicology, Graduate College, The University of Iowa, Iowa City, IA, USA.
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, 100 Oakdale Campus #219 IREH, Iowa City, IA, 52242-5000, USA.
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46
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Uwimana E, Li X, Lehmler HJ. Human Liver Microsomes Atropselectively Metabolize 2,2',3,4',6-Pentachlorobiphenyl (PCB 91) to a 1,2-Shift Product as the Major Metabolite. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:6000-6008. [PMID: 29659268 PMCID: PMC5966832 DOI: 10.1021/acs.est.8b00612] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Polychlorinated biphenlys (PCBs) and their hydroxylated metabolites (OH-PCBs) have been implicated in neurodevelopmental disorders. Several neurotoxic PCBs, such as PCB 91, are chiral because they form stable rotational isomers, or atropisomers, that are nonsuperimposable mirror images of each other. Because only limited information about the metabolism of these PCBs by human cytochrome P450 (P450) enzymes is available, we investigated the biotransformation of PCB 91 to OH-PCBs by human liver microsomes (HLMs). Racemic PCB 91 was incubated with pooled or individual donor HLMs at 37 °C, and levels and chiral signatures of PCB 91 and its metabolites were determined. Several OH-PCBs were formed in the order 2,2',4,4',6-pentachlorobiphenyl-3-ol (3-100; 1,2 shift product) > 2,2',3,4',6-pentachlorobiphenyl-5-ol (5-91) ≫ 2,2',3,4',6-pentachlorobiphenyl-4-ol (4-91) ≫ 4,5-dihydroxy-2,2',3,4',6-pentachlorobiphenyl (4,5-91). Metabolite formation rates displayed interindividual variability. The first eluting atropisomers of PCB 91, 3-100 and 4-91, and the second eluting atropisomer of 5-91 were enriched in most metabolism studies. The unexpected, preferential formation of a 1,2-shift product and the variability of the OH-PCBs profiles in experiments with individual donor HLMs underline the need for further systematic studies of the atropselective metabolism of PCBs in humans.
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Affiliation(s)
| | | | - Hans-Joachim Lehmler
- Corresponding Author: Dr. Hans-Joachim Lehmler, The University of Iowa, Department of Occupational and Environmental Health, University of Iowa Research Park, #164 MTF, Iowa City, IA 52242-5000, Phone: (319) 335-4310, Fax: (319) 335-4290,
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47
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Liu YY, Xiao JJ, Fu YY, Liao M, Cao HQ, Shi YH. Study of Factors Influencing the Bioaccessibility of Triazolone in Cherry Tomatoes Using a Static SHIME Model. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15050993. [PMID: 29762491 PMCID: PMC5982032 DOI: 10.3390/ijerph15050993] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 05/05/2018] [Accepted: 05/09/2018] [Indexed: 12/20/2022]
Abstract
Estimating the influence of bioaccessibility of pesticide residues in fruits and vegetables on dietary exposure is a challenge for human health risk assessment. This study investigated the bioaccessibility of pesticide residues in cherry tomatoes and contributing factors (digestion time, pH, solid/liquid ratio, and dietary nutrition) using an in vitro test simulating the human gastrointestinal tract. pH had the largest effect on triazolone precipitation in the simulated gastric intestinal juice, which had a significant impact on the bioaccessibility. The bioaccessibility of triazolone in the intestinal stage was slightly higher than that in the stomach stage, owing to bile salts and pancreatic enzymes present in the intestinal juice. The bioaccessibility of triazolone did not change significantly with digestion time. In the gastric stage, there was a logarithmic relationship between the bioaccessibility and solid/liquid ratio (R² = 0.9941). The addition of oil significantly changed the bioaccessibility in the gastrointestinal stage. Protein and dietary fiber only affected bioaccessibility in the stomach stage. Dietary nutrition can reduce the release of pesticides from fruits and vegetables into the stomach, sharply reducing the bioaccessibility, and the dietary exposure of pesticide residues in fruits and vegetables can be properly evaluated.
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Affiliation(s)
- Yu-Ying Liu
- School of Resource & Environment, Anhui Agricultural University, Hefei 230036, China.
- Provincial Key Laboratory for Agri-Food Safety, Anhui Agricultural University, Hefei 230036, China.
| | - Jin-Jing Xiao
- Provincial Key Laboratory for Agri-Food Safety, Anhui Agricultural University, Hefei 230036, China.
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, China.
| | - Yun-Yao Fu
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, China.
| | - Min Liao
- Provincial Key Laboratory for Agri-Food Safety, Anhui Agricultural University, Hefei 230036, China.
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, China.
| | - Hai-Qun Cao
- Provincial Key Laboratory for Agri-Food Safety, Anhui Agricultural University, Hefei 230036, China.
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, China.
| | - Yan-Hong Shi
- School of Resource & Environment, Anhui Agricultural University, Hefei 230036, China.
- Provincial Key Laboratory for Agri-Food Safety, Anhui Agricultural University, Hefei 230036, China.
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48
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Adams KJ, Smith NF, Ramirez CE, Fernandez-Lima F. Discovery and targeted monitoring of polychlorinated biphenyl metabolites in blood plasma using LC-TIMS-TOF MS. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2018; 427:133-140. [PMID: 29915519 PMCID: PMC6003708 DOI: 10.1016/j.ijms.2017.11.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In the present work, the potential for rapid, targeted analysis of hydroxylated metabolites of polychlorinated biphenyls (OH-PCBs) in diluted human blood plasma using liquid chromatography coupled with trapped ion mobility spectrometry and TOF high resolution mass spectrometry (LC-TIMS-TOF MS) was evaluated. Experimental OH-PCB collisional cross section (CCSN2) and gas-phase candidate structures (<3% error) are reported for the first time and used, in addition to the LC retention time and accurate m/z, as OH-PCB identification features in order to increase the detection selectivity. The proposed LC-TIMS-TOF MS workflow combines a "dilute-and-shoot" sample preparation strategy, a robust liquid chromatography step, a high-resolving power mobility separation (R ~ 150-250) and high-resolution mass spectrometry (R ~ 30-40k) for the separation, identification and quantification of common OH-PCB isomers with limits of detection comparable to traditional workflows (e.g., LOD and LOQ of ~10 pg/mL and ~50 pg/mL, respectively). The higher selectivity and low detection limits provides multiple advantages compared to current methodologies that typically require long, labor-intensive preparation and/or derivatization steps prior to gas or liquid chromatography-mass spectrometry.
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Affiliation(s)
- Kendra J. Adams
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, United States
| | - Natalie F. Smith
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, United States
| | - Cesar E. Ramirez
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, United States
| | - Francisco Fernandez-Lima
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, United States
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, United States
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49
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Wang S, Luo C, Zhang D, Wang Y, Song M, Yu Z, Wang Y, Zhang G. Reflection of Stereoselectivity during the Uptake and Acropetal Translocation of Chiral PCBs in Plants in the Presence of Copper. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:13834-13841. [PMID: 29096434 DOI: 10.1021/acs.est.7b03350] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Plant uptake and acropetal translocation of polychlorinated biphenyls (PCBs) is a major concern, with many uncertainties, especially when plants are exposed to coexisting PCBs and metals. Studying atropisomer selectivity behavior is a well-proven method for identifying the biotransformation process of chiral PCBs in plants. This study investigated the uptake, translocation, and stereoselectivity of PCB95 and PCB136 (3 μg/L in hydroponics and 200 μg/kg in pot experiment) by monocot corn and dicot sunflower after copper (Cu) exposure (50 μmol/L in hydroponics and 400 mg/kg in pot experiment). Cu exposure led to significantly increased PCBs accumulation in roots and enhanced their acropetal translocation from roots to shoots, attributed to Cu-induced root damage. In the absence of Cu, the first-eluting enantiomer of PCB95 and second-eluting enantiomer of PCB136 were preferentially enriched in the shoots and roots of both the monocot and the dicot, and the enantioselectivity of chiral PCBs was more pronounced in shoots than in roots. Cu exposure significantly reduced the stereoselectivity of PCB95 and PCB136 in the defective root system, implying that PCB95 and PCB136 uptake into roots after Cu exposure changed from active biotransformation to passive diffusion. Our findings suggest that the ecological risk of PCB95 and PCB136 uptake and accumulation in plants is underestimated at sites cocontaminated with metals and PCBs and, for the first time, reveal the mechanism associated with the uptake and biotransformation of chiral PCBs in plants after exposure to both heavy metals and chiral PCBs.
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Affiliation(s)
- Shaorui Wang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou 510640, China
| | - Chunling Luo
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou 510640, China
- College of Natural Resources and Environment, South China Agricultural University , Guangzhou, 510642, China
| | - Dayi Zhang
- School of Environment, Tsinghua University , Beijing, 100084, China
| | - Yan Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology , Dalian 116024, China
| | - Mengke Song
- College of Natural Resources and Environment, South China Agricultural University , Guangzhou, 510642, China
| | - Zhiqiang Yu
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou 510640, China
| | - Yujie Wang
- School of Environmental Science and Engineering, Guangdong University of Technology , Guangzhou, 510006, China
| | - Gan Zhang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences , Guangzhou 510640, China
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50
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Shi YH, Xiao JJ, Feng RP, Liu YY, Liao M, Wu XW, Hua RM, Cao HQ. In-vitro bioaccessibility of five pyrethroids after human ingestion and the corresponding gastrointestinal digestion parameters: A contribution for human exposure assessments. CHEMOSPHERE 2017; 182:517-524. [PMID: 28521167 DOI: 10.1016/j.chemosphere.2017.05.081] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 04/27/2017] [Accepted: 05/13/2017] [Indexed: 06/07/2023]
Abstract
Bioaccessibility is a crucial parameter in assessing the absorption of contaminants during the human digestive process, but few studies have involved the differences in the bioaccessibilities of pesticides. To investigate the mode of using the in vitro bioaccessibility to refine estimates of dietary exposure to pesticide residues, this study measured the bioaccessibilities of five pyrethroids in apples, and then, it modelled physicochemical predictors (gastrointestinal pH, digestive times, and the solid-liquid (S/L) ratio) of the bioaccessibilities of pyrethroids. Apple samples of gastric and intestinal phase digestive juices were obtained from an in vitro simulated digestion model. Our survey of in vitro digestion models found that the bioaccessibilities ranged from 4.42% to 31.22% and 10.58%-35.63% in the gastric and intestinal phases, respectively. A sharp trend similar to a normal distribution was observed between the bioaccessibilities and pH values. The bioaccessibility reached its highest value at a pH of 1.91 in the simulated gastric juice and did not significantly change with an increase of the digestive time. A significant negative correlation occurred between the bioaccessibility and S/L ratio, which followed a logarithmic equation. The correlation coefficients (R2) ranged from 0.9259 to 0.9831 and 0.9077 to 0.9960 in the simulated gastric and intestinal juice, respectively, suggested that both the pH value and S/L ratio were the main factors affecting the bioaccessibility. Furthermore, a combination of the acceptable daily intake (ADI) and bioaccessibility for human exposure assessments indicated the implication that traditional risk assessment using ADI may seriously overestimate the actual risk.
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Affiliation(s)
- Yan-Hong Shi
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, China; Provincial Key Laboratory for Agri-Food Safety, Anhui Province, China
| | - Jin-Jing Xiao
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, China
| | - Rong-Peng Feng
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, China
| | - Yu-Ying Liu
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, China
| | - Min Liao
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, China; Provincial Key Laboratory for Agri-Food Safety, Anhui Province, China
| | - Xiang-Wei Wu
- Provincial Key Laboratory for Agri-Food Safety, Anhui Province, China
| | - Ri-Mao Hua
- Provincial Key Laboratory for Agri-Food Safety, Anhui Province, China
| | - Hai-Qun Cao
- School of Plant Protection, Anhui Agricultural University, Hefei 230036, China; Provincial Key Laboratory for Agri-Food Safety, Anhui Province, China.
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