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Miret NV, Pontillo CA, Zárate LV, Kleiman de Pisarev D, Cocca C, Randi AS. Impact of endocrine disruptor hexachlorobenzene on the mammary gland and breast cancer: The story thus far. ENVIRONMENTAL RESEARCH 2019; 173:330-341. [PMID: 30951959 DOI: 10.1016/j.envres.2019.03.054] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 02/19/2019] [Accepted: 03/21/2019] [Indexed: 06/09/2023]
Abstract
Breast cancer incidence is increasing globally and exposure to endocrine disruptors has gained importance as a potential risk factor. Hexachlorobenzene (HCB) was once used as a fungicide and, despite being banned, considerable amounts are still released into the environment. HCB acts as an endocrine disruptor in thyroid, uterus and mammary gland and was classified as possibly carcinogenic to human. This review provides a thorough analysis of results obtained in the last 15 years of research and evaluates data from assays in mammary gland and breast cancer in diverse animal models. We discuss the effects of environmentally relevant HCB concentrations on the normal mammary gland and different stages of carcinogenesis, and attempt to elucidate its mechanisms of action at molecular level. HCB weakly binds to the aryl hydrocarbon receptor (AhR), activating both membrane (c-Src) and nuclear pathways. Through c-Src stimulation, AhR signaling interacts with other membrane receptors including estrogen receptor-α, insulin-like growth factor-1 receptor, epidermal growth factor receptor and transforming growth factor beta 1 receptors. In this way, several pathways involved in mammary morphogenesis and breast cancer development are modified, inducing tumor progression. HCB thus stimulates epithelial cell proliferation, preneoplastic lesions and alterations in mammary gland development as well as neoplastic cell migration and invasion, metastasis and angiogenesis in breast cancer. In conclusion, our findings support the hypothesis that the presence and bioaccumulation of HCB in high-fat tissues and during highly sensitive time windows such as pregnancy, childhood and adolescence make exposure a risk factor for breast tumor development.
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Affiliation(s)
- Noelia V Miret
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Laboratorio de Efectos Biológicos de Contaminantes Ambientales, Paraguay 2155, 5to piso, CP1121, Buenos Aires, Argentina.
| | - Carolina A Pontillo
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Laboratorio de Efectos Biológicos de Contaminantes Ambientales, Paraguay 2155, 5to piso, CP1121, Buenos Aires, Argentina.
| | - Lorena V Zárate
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Laboratorio de Efectos Biológicos de Contaminantes Ambientales, Paraguay 2155, 5to piso, CP1121, Buenos Aires, Argentina.
| | - Diana Kleiman de Pisarev
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Laboratorio de Efectos Biológicos de Contaminantes Ambientales, Paraguay 2155, 5to piso, CP1121, Buenos Aires, Argentina.
| | - Claudia Cocca
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Laboratorio de Radioisótopos, Junín 954, subsuelo, CP1113, Buenos Aires, Argentina.
| | - Andrea S Randi
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Laboratorio de Efectos Biológicos de Contaminantes Ambientales, Paraguay 2155, 5to piso, CP1121, Buenos Aires, Argentina.
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2
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Castilla R, Asuaje A, Rivière S, Romero CG, Martín P, Cao G, Kleiman de Pisarev D, Milesi V, Alvarez L. Environmental pollutant hexachlorobenzene induces hypertension in a rat model. CHEMOSPHERE 2018; 195:576-584. [PMID: 29277037 DOI: 10.1016/j.chemosphere.2017.11.117] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 10/27/2017] [Accepted: 11/21/2017] [Indexed: 05/10/2023]
Abstract
Hexachlorobenzene (HCB) is a dioxin-like environmental pollutant, widely distributed in the environment. New research links exposure to high levels of persistent organic environmental toxicants to cardiovascular disease, however little is known about the effect of HCB on vascular function and on blood pressure. The purpose of the present study was to evaluate biochemical and cardiovascular changes resulting from subchronic HCB exposure. Adult female Sprague-Dawley rats were treated with vehicle or HCB (5 or 500 mg/kg b.w) for 45 days. Systolic blood pressure (BP), recorded by tail cuff plethysmography, was significantly increased at 35, 40 and 45 days of 500 mg/kg HCB-treatment. HCB (500 mg/kg) increased arterial thickness, while both 5 and 500 mg/kg HCB decreased proliferating cell nuclear antigen (PCNA) protein levels and cellular nuclei in abdominal aortas indicating a hypertrophic process. Also, aortas from both groups of HCB-treated rats presented higher sensitivity to noradrenalin (NA) and a significant decrease in maximum contractile response. Arteries from 500 mg/kg HCB-treated rats showed a significant increase in the levels of transforming growth factor-β1 (TGF-β1) mRNA and angiotensin II type1 receptor (AT1), and a significant decrease in estrogen receptor alpha (ERα), endothelial nitric oxidide synthase (eNOS) protein expression and deiodinase II (DII) mRNA levels. In conclusion, we have demonstrated for the first time that subchronic HCB administration significantly increases BP and alters associated cardiovascular parameters in rats. In addition, HCB alters the expression of key vascular tissue molecules involved in BP regulation, such as TGF-β1, AT1, ERα, eNOS and DII.
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Affiliation(s)
- Rocío Castilla
- Universidad de Buenos Aires, CONICET, Instituto de Investigaciones Cardiológicas (ININCA), C1122AAJ Buenos Aires, Argentina.
| | - Agustín Asuaje
- Universidad Nacional de La Plata, Facultad de Ciencias Exactas, CONICET, Instituto de Estudios Inmunológicos y Fisiopatológicos (IIFP), 1900, La Plata, Buenos Aires, Argentina.
| | - Stéphanie Rivière
- Universidad de Buenos Aires, CONICET, Instituto de Investigaciones Cardiológicas (ININCA), C1122AAJ Buenos Aires, Argentina.
| | - Caimi Giselle Romero
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Laboratorio de Efectos Biológicos de Contaminantes Ambientales, C1121ABG, Buenos Aires, Argentina.
| | - Pedro Martín
- Universidad Nacional de La Plata, Facultad de Ciencias Exactas, CONICET, Instituto de Estudios Inmunológicos y Fisiopatológicos (IIFP), 1900, La Plata, Buenos Aires, Argentina.
| | - Gabriel Cao
- Universidad de Buenos Aires, CONICET, Instituto de Investigaciones Cardiológicas (ININCA), C1122AAJ Buenos Aires, Argentina.
| | - Diana Kleiman de Pisarev
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Laboratorio de Efectos Biológicos de Contaminantes Ambientales, C1121ABG, Buenos Aires, Argentina.
| | - Verónica Milesi
- Universidad Nacional de La Plata, Facultad de Ciencias Exactas, CONICET, Instituto de Estudios Inmunológicos y Fisiopatológicos (IIFP), 1900, La Plata, Buenos Aires, Argentina.
| | - Laura Alvarez
- Universidad de Buenos Aires, Facultad de Medicina, Departamento de Bioquímica Humana, Laboratorio de Efectos Biológicos de Contaminantes Ambientales, C1121ABG, Buenos Aires, Argentina.
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3
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Lehmann GM, Verner MA, Luukinen B, Henning C, Assimon SA, LaKind JS, McLanahan ED, Phillips LJ, Davis MH, Powers CM, Hines EP, Haddad S, Longnecker MP, Poulsen MT, Farrer DG, Marchitti SA, Tan YM, Swartout JC, Sagiv SK, Welsh C, Campbell JL, Foster WG, Yang RS, Fenton SE, Tornero-Velez R, Francis BM, Barnett JB, El-Masri HA, Simmons JE. Improving the risk assessment of lipophilic persistent environmental chemicals in breast milk. Crit Rev Toxicol 2014; 44:600-17. [PMID: 25068490 PMCID: PMC4115797 DOI: 10.3109/10408444.2014.926306] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Lipophilic persistent environmental chemicals (LPECs) have the potential to accumulate within a woman's body lipids over the course of many years prior to pregnancy, to partition into human milk, and to transfer to infants upon breastfeeding. As a result of this accumulation and partitioning, a breastfeeding infant's intake of these LPECs may be much greater than his/her mother's average daily exposure. Because the developmental period sets the stage for lifelong health, it is important to be able to accurately assess chemical exposures in early life. In many cases, current human health risk assessment methods do not account for differences between maternal and infant exposures to LPECs or for lifestage-specific effects of exposure to these chemicals. Because of their persistence and accumulation in body lipids and partitioning into breast milk, LPECs present unique challenges for each component of the human health risk assessment process, including hazard identification, dose-response assessment, and exposure assessment. Specific biological modeling approaches are available to support both dose-response and exposure assessment for lactational exposures to LPECs. Yet, lack of data limits the application of these approaches. The goal of this review is to outline the available approaches and to identify key issues that, if addressed, could improve efforts to apply these approaches to risk assessment of lactational exposure to these chemicals.
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Affiliation(s)
- Geniece M. Lehmann
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, US
| | - Marc-André Verner
- Channing Division of Network Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, US
| | | | - Cara Henning
- ICF International, Research Triangle Park, NC, US
| | - Sue Anne Assimon
- Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD, US
| | - Judy S. LaKind
- LaKind Associates, LLC, Catonsville, MD, US
- University of Maryland School of Medicine, Baltimore, MD, US
- Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, PA, US
| | - Eva D. McLanahan
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, US
| | - Linda J. Phillips
- Office of Research and Development, U.S. Environmental Protection Agency, Washington, DC, US
| | - Matthew H. Davis
- Office of Children’s Health Protection, U.S. Environmental Protection Agency, Washington, DC, US
| | - Christina M. Powers
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, US
| | - Erin P. Hines
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, US
| | - Sami Haddad
- Department of Environmental Health and Occupational Health, IRSPUM (Université de Montréal Public Health Research Institute), Université de Montréal, Montreal, Quebec, Canada
| | - Matthew P. Longnecker
- National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, US
| | | | | | - Satori A. Marchitti
- Office of Research and Development, U.S. Environmental Protection Agency, Athens, GA, US
| | - Yu-Mei Tan
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, US
| | - Jeffrey C. Swartout
- Office of Research and Development, U.S. Environmental Protection Agency, Cincinnati, OH, US
| | - Sharon K. Sagiv
- Department of Environmental Health, Boston University School of Public Health, Boston, MA, US
| | - Clement Welsh
- Division of Toxicology and Human Health Sciences, Agency for Toxic Substances and Disease Registry, Atlanta, GA, US
| | - Jerry L. Campbell
- The Hamner Institutes for Health Sciences, Research Triangle Park, NC, US
| | - Warren G. Foster
- Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada
| | - Raymond S.H. Yang
- Quantitative and Computational Toxicology Group, Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, US
| | - Suzanne E. Fenton
- National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC, US
| | - Rogelio Tornero-Velez
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, US
| | | | - John B. Barnett
- Department of Microbiology, Immunology, and Cell Biology, West Virginia University School of Medicine, Morgantown, WV, US
| | - Hisham A. El-Masri
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, US
| | - Jane Ellen Simmons
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, US
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Alterations in c-Src/HER1 and estrogen receptor α signaling pathways in mammary gland and tumors of hexachlorobenzene-treated rats. Toxicology 2012; 293:68-77. [DOI: 10.1016/j.tox.2011.12.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Revised: 12/07/2011] [Accepted: 12/28/2011] [Indexed: 11/18/2022]
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Aylward LL, Hays SM, Gagné M, Nong A, Krishnan K. Biomonitoring equivalents for hexachlorobenzene. Regul Toxicol Pharmacol 2010; 58:25-32. [PMID: 20547196 DOI: 10.1016/j.yrtph.2010.06.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 06/03/2010] [Accepted: 06/03/2010] [Indexed: 11/25/2022]
Abstract
Recent efforts worldwide have resulted in a growing database of measured concentrations of chemicals in blood and urine samples taken from the general population. However, few tools exist to assist in the interpretation of the measured values in a health risk context. Biomonitoring equivalents (BEs) are defined as the concentration or range of concentrations of a chemical or its metabolite in a biological medium (blood, urine, or other medium) that is consistent with an existing health-based exposure guideline. This study reviews available health-based exposure guidance values for hexachlorobenzene (HCB) from Health Canada, the United States Environmental Protection Agency (US EPA), the US Agency for Toxic Substances and Disease Registry (ATSDR) and World Health Organization (WHO). HCB liver tissue concentrations in chronic rodent bioassays and information on human elimination rates and tissue distribution of HCB were extrapolated to estimate serum lipid-adjusted HCB concentrations that are consistent with the exposure guidance values for HCB. Estimated serum lipid-adjusted HCB concentrations ranging from 16 to 250 ng/g lipid were consistent with non-cancer-based exposure guidance values from various agencies. Concentrations associated with cancer risk-specific doses at target risk levels of interest were also estimated. These BE values may be used as screening tools for evaluation of population biomonitoring data for HCB in a risk assessment context and can assist in prioritization of the potential need for additional risk assessment efforts for HCB relative to other chemicals.
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6
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Opinion of the Scientific Panel on contaminants in the food chain [CONTAM] related to Hexachlorobenzene as undesirable substance in animal feed. EFSA J 2006. [DOI: 10.2903/j.efsa.2006.402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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7
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Lu Y, Lohitnavy M, Reddy MB, Lohitnavy O, Ashley A, Yang RSH. An updated physiologically based pharmacokinetic model for hexachlorobenzene: incorporation of pathophysiological states following partial hepatectomy and hexachlorobenzene treatment. Toxicol Sci 2006; 91:29-41. [PMID: 16481338 DOI: 10.1093/toxsci/kfj133] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Physiologically based pharmacokinetic (PBPK) modeling is generally used for describing xenobiotic disposition in animals and humans with normal physiological conditions. We describe here an updated PBPK model for hexachlorobenzene (HCB) in male F344 rats with the incorporation of pathophysiological conditions. Two more features contribute to the distinctness of this model from the earlier published versions. This model took erythrocyte binding into account, and a particular elimination process of HCB, the plasma-to-gastrointestinal (GI) lumen passive diffusion (i.e., exsorption), was incorporated. Our PBPK model was developed using data mined from multiple pharmacokinetic studies in the literature, and then modified to simulate HCB disposition under the conditions of our integrated pharmacokinetics/liver foci bioassay. This model included plasma, erythrocytes, liver, fat, rapidly and slowly perfused compartments, and GI lumen. To account for the distinct characteristics of HCB absorption, the GI lumen was split into an upper and a lower part. HCB was eliminated through liver metabolism and the exsorption process. The pathophysiological changes after partial hepatectomy, such as alterations in the liver and body weights and fat volume, were incorporated in our model. With adjustment of the transluminal diffusion-related parameters, the model adequately described the data from the literature and our bioassay. Our PBPK model simulation suggests that HCB absorption and exsorption processes depend on exposure conditions; different exposure conditions dictate different absorption and exsorption rates. This model forms a foundation for our further exploration of the quantitative relationship between HCB exposure and development of preneoplastic liver foci.
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Affiliation(s)
- Yasong Lu
- Quantitative and Computational Toxicology Group, Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado 80523, USA
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8
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Randi AS, Cocca C, Carbone V, Nuñez M, Croci M, Gutiérrez A, Bergoc R, Kleiman de Pisarev DL. Hexachlorobenzene is a tumor co-carcinogen and induces alterations in insulin-growth factors signaling pathway in the rat mammary gland. Toxicol Sci 2005; 89:83-92. [PMID: 16237195 DOI: 10.1093/toxsci/kfj023] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Hexachlorobenzene (HCB) is a widespread environmental pollutant. Controversy still exists about the breast carcinogenic properties of organochlorines in humans. The ligands, receptors, and related signaling proteins of the insulin growth factor family are involved in the regulation of breast-cancer cell growth. The aims of this study were to determine: (1) whether HCB is co-carcinogenic in a medium term assay of N-nitroso N-methylurea (NMU)-induced mammary tumors in rats; (2) the effect of HCB on insulin receptor (IR), insulin-like growth factor-I receptor (IGF-IR) and insulin receptor substrate-1 (IRS-1) levels and on IRS-1 phosphorylation; (3) microsomal and cytosolic Protein Tyrosine Kinase (PTK) activities in mammary glands and NMU-induced tumors. Sprague Dawley rats were injected with 50 mg/kg body weight of NMU at 50, 80, and 110 days old. HCB (100 mg/kg body weight) was administered three times a week from 65 to 110 days of age. Rats were separated in four groups: control, NMU, HCB, and NMU-HCB. HCB alone did not induce tumor development. Parameters of tumor development were increased in NMU-HCB compared to NMU rats. A higher cellular undifferentiation was observed in NMU-HCB tumors. IR, IGF-IR, and IRS-1 levels were higher in HCB than in controls. Conversely IGF-IR levels decreased in NMU-HCB vs. NMU group. The IRS-1 phosphorylation increased in HCB rats; however, it decreased in NMU-HCB vs. NMU. HCB decreased microsomal PTK activity in tumors. This study showed for the first time that HCB is a co-carcinogenic agent in NMU-induced mammary tumors in rats. Our results suggest that the IR and/or IGF-IR signaling pathway may be involved in the mechanism of action of HCB.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Animals
- Carcinogenicity Tests
- Carcinogens/toxicity
- Cocarcinogenesis
- Disease Models, Animal
- Drug Therapy, Combination
- Female
- Hexachlorobenzene/classification
- Hexachlorobenzene/toxicity
- Insulin Receptor Substrate Proteins
- Insulin-Like Growth Factor I/metabolism
- Mammary Glands, Animal/drug effects
- Mammary Glands, Animal/metabolism
- Mammary Neoplasms, Animal/chemically induced
- Mammary Neoplasms, Animal/metabolism
- Mammary Neoplasms, Animal/pathology
- Methylnitrosourea
- Phosphoproteins/metabolism
- Protein-Tyrosine Kinases/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, IGF Type 1/metabolism
- Receptor, Insulin/metabolism
- Signal Transduction/drug effects
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Affiliation(s)
- Andrea S Randi
- Departamento de Bioquímica Humana, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, 5to piso, Buenos Aires, CP 1121, Argentina.
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9
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Abstract
Toxic organochlorines that are present in food are lipophilic and carried by chylomicrons. We have studied the clearance of an organochlorine, hexachlorobenzene, from chylomicrons. Chylomicrons were obtained from mesenteric lymph of rats that were intraduodenally given 14C-hexachlorobenzene and 3H-triolein. The labeled chylomicrons were injected intravenously into recipient rats, and the clearance of isotopes was followed. Surprisingly, the hexachlorobenzene disappeared from the plasma more rapidly than the triolein. This unexpected result raises questions about the manner in which hexachlorobenzene is delivered to tissues. The tissue distribution of the hexachlorobenzene is consistent with its rapid uptake.
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Affiliation(s)
- Ronald J Jandacek
- The University of Cincinnati, Department of Pathology, Cincinnati, Ohio 45237, USA.
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Alvarez L, Hernández S, Martinez-de-Mena R, Kolliker-Frers R, Obregón MJ, Kleiman de Pisarev DL. The role of type I and type II 5′ deiodinases on hexachlorobenzene-induced alteration of the hormonal thyroid status. Toxicology 2005; 207:349-62. [PMID: 15664263 DOI: 10.1016/j.tox.2004.10.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2004] [Revised: 07/12/2004] [Accepted: 10/11/2004] [Indexed: 10/26/2022]
Abstract
Treatment of male Wistar rats with hexachlorobenzene (HCB) (1000 mg/kg b.w.) for 3-30 days decreases circulating levels of thyroxine (T4) but does not affect triiodothyronine (T3). Time courses were determined for 5' deiodinase type I (5' D-I) activity in thyroid, liver, and kidney and 5' deiodinase type II (5' D-II) activity in brown adipose tissue (BAT) to test the possibility that increased deiodinase activity might contribute to the maintenance of the serum T3 level. Specific 5' D-I activity was increased in the thyroid at 21 days and thereafter. No significant changes were observed in the liver, however, total 5' D-I activity in this tissue was increased at 30 days of treatment as a consequence of liver weight enhancement. HCB decreased kidney 5' D-I activity after 15 days, and BAT 5' D-II activity after 21 days of treatment. Total body 5' D-I activity was significantly increased by 30 days of HCB-treatment. HCB increased the activity of hepatic T4 uridine diphosphoglucuronosyl transferase (UDPGT) in a time-dependent manner, without changes in T3 UDPGT. We propose that increased T4 to T3 conversion in the thyroid and in the greatly enlarged liver may account for the maintenance of serum T3 concentration in hypothyroxinemic HCB-treated rats.
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Affiliation(s)
- L Alvarez
- Departamento de Bioquímica Humana, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, Buenos Aires 1121, Argentina.
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11
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Cochón AC, González N, San Martín de Viale LC. Effects of the porphyrinogenic compounds hexachlorobenzene and 3,5-diethoxycarbonyl-1,4-dihydrocollidine on polyamine metabolism. Toxicology 2002; 176:209-19. [PMID: 12093617 DOI: 10.1016/s0300-483x(02)00145-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The naturally occurring polyamines--putrescine, spermidine and spermine--are organic cations present in all living cells and essential for cell growth and differentiation. The aim of the present study was to extend the investigations on the effects of porphyrinogenic compounds on polyamine metabolism. This was achieved by studying putrescine, spermidine and spermine levels in a model of acute porphyria, i.e. 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced porphyria, and in a model of non-acute porphyria, i.e. hexachlorobenzene (HCB)-induced porphyria. HCB administration to female Wistar rats for 7, 14, 21, 28 and 56 days did not alter polyamine levels in liver, even though rats presented clear signs of HCB-induced porphyria. In contrast to HCB, DDC treatment resulted in a remarkable increase in putrescine levels in the liver of female and male Sprague-Dawley rats. This increase was due, at least in part, to ornithine decarboxylase (ODC) activation. DDC induction of putrescine levels did not show organ specificity, since it could also be seen in adrenal gland. Interestingly, the deregulation of polyamine biosynthesis occurred concomitantly with the deregulation of the heme biosynthetic pathway. In addition to porphyria, it is known that DDC intoxication affects several proteins of the hepatocyte cytoskeleton. It is suggested that DDC-induced increase in ODC activity and putrescine levels may be an early event contributing to alter the cytoskeleton.
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Affiliation(s)
- Adriana Cristina Cochón
- Laboratorio de Porfirias Experimentales y Metabolismo del Hemo, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Nuñez, 1428 Buenos Aires, Argentina
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12
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Cochón AC, San Martín de Viale LC, Billi de Catabbi SC. Phospholipid alterations elicited by hexachlorobenzene in rat brain are strain-dependent and porphyria-independent. Comp Biochem Physiol C Toxicol Pharmacol 2001; 130:199-207. [PMID: 11574289 DOI: 10.1016/s1532-0456(01)00240-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hexachlorobenzene (HCB) alters phospholipid and heme metabolisms in the liver and Harderian gland. The effects of HCB on phospholipid metabolism, in an organ considered to be non-responsive to its porphyrinogenic effects, remain to be studied. Therefore, as the brain is an organ with this feature, this paper analyzes the effects of HCB on brain phospholipid composition in order to investigate if there is any relationship between HCB-induced porphyrin metabolism disruption and phospholipid alterations. For this purpose, a time-course study of HCB effects on brain phospholipids was performed in two strains of rats differing in their susceptibility to acquire hepatic porphyria: Chbb THOM (low); and Wistar (high). This paper shows for the first time that rat brain phospholipids are affected by HCB exposure. Comparative studies show that HCB-induced disturbances in brain phospholipid patterns are time and strain-dependent. Thus, whereas major phospholipids, phosphatidylcholine and phosphatidylethanolamine were more altered in Wistar rats, minor phospholipids, phosphatidylinositol and phosphatidylserine were more affected in Chbb THOM rats. HCB intoxication led to a sphingomyelin/phosphatidylcholine molar ratio lower than the normal, in both strains. As was expected, brain porphyrin content was not altered by HCB intoxication in either strain. It can be concluded that HCB is able to alter brain phospholipid metabolism in a strain-dependent fashion, and in the absence of alterations in brain heme metabolism. In addition, HCB-induced disturbances in brain phospholipids were not related to the degree of hepatic porphyria achieved by the rats.
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Affiliation(s)
- A C Cochón
- Laboratorio de Porfirias Experimentales y Metabolismo del Hemo, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Nuñez, 1428, Buenos Aires, Argentina
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13
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Hendriks AJ, van der Linde A, Cornelissen G, Sijm DT. The power of size. 1. Rate constants and equilibrium ratios for accumulation of organic substances related to octanol-water partition ratio and species weight. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2001; 20:1399-1420. [PMID: 11434281 DOI: 10.1002/etc.5620200703] [Citation(s) in RCA: 149] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Most of the thousands of substances and species that risk assessment has to deal with are not investigated empirically because of financial, practical, and ethical constraints. To facilitate extrapolation, we have developed a model for accumulation kinetics of organic substances as a function of the octanol-water partition ratio (Kow) of the chemical and the weight, lipid content, and trophic level of the species. The ecological parameters were obtained from a previous review on allometric regressions. The chemical parameters, that is, resistances that substances encounter in water and lipid layers of organisms, were calibrated on 1,939 rate constants for absorption from water for assimilation from food and for elimination. Their ratio was validated on 37 laboratory bioconcentration and biomagnification regressions and on 2,700 field bioaccumulation data. The rate constant for absorption increased with the hydrophobicity of the substances with a Kow up to about 1,000 and then leveled off, decreasing with the weight of the species. About 39% of the variation was explained by the model, while deviations of more than a factor of 5 were noted for labile, large, and less hydrophobic molecules as well as for algae, mollusks, and arthropods. The efficiency for assimilation of contaminants from food was determined mainly by the food digestibility and thus by the trophic level of the species. A distinction was made between substances that are stable, that is, with a minimum elimination only, and those that are labile, that is, with an excess elimination probably largely due to biotransformation. The rate constant for minimum elimination decreased with the hydrophobicity of the substance and the weight of the species. About 70% of the variation was explained by the model, while deviations of more than a factor of 5 were noted for algae, terrestrial plants, and benthic animals. Labile substances were eliminated faster than isolipophilic stable compounds, but differences in laboratory elimination and accumulation were small compared with those in field accumulation. Excess elimination by vertebrates was faster than by invertebrates. Differences between terrestrial and aquatic species were attributed to water turnover rates, whereas differences between trophic levels were due to the food digestibility. Food web accumulation, expressed as organism-organic solids and organism-food concentrations ratios could be largely explained by ecological variables only. The model is believed to facilitate various types of scientific interpretation as well as environmental risk assessment.
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Affiliation(s)
- A J Hendriks
- Institute for Inland Water Management and Waste Water Treatment, P.O. Box 17, 8200 AA Lelystad, The Netherlands.
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van der Linde A, Hendriks AJ, Sijm DT. Estimating biotransformation rate constants of organic chemicals from modeled and measured elimination rates. CHEMOSPHERE 2001; 44:423-435. [PMID: 11459147 DOI: 10.1016/s0045-6535(00)00213-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In this study, biotransformation rate constants are estimated for a large set of organic compounds. Biotransformation (km) is considered part of the total elimination, further consisting of physico-chemical elimination to water (kw), depuration by feces (kf) and growth dilution (gamma). Existing models are used to estimate kw and kf, and gamma. The difference between measured elimination rate constants and the sum of predicted elimination rate constants for water, feces and growth indicates the ration of biotransformation in the total elimination. In all examined animal classes, polycyclic aromatic hydrocarbons seem to be metabolized at an intermediate rate. Because of the relative low hydrophobicity of some of the studied compounds, their physico-chemical elimination rate constant is relatively high, and the relative contribution of metabolism to total elimination of these compounds is therefore relatively low. Fish seem to be capable of metabolizing chlorodibenzo-p-dioxins and -furans, DDT, chloroanilines and phenol.
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Affiliation(s)
- A van der Linde
- Department of Chemistry and Ecotoxicology, Institute for Inland Water Management and Waste Water Treatment, Lelystad, The Netherlands
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Aldonatti C, de Viale LC. Heme metabolism after discontinued hexachlorobenzene administration in rats: possible irreversible changes and biomarker for hexachlorobenzene persistence. Comp Biochem Physiol C Toxicol Pharmacol 2000; 127:165-75. [PMID: 11083027 DOI: 10.1016/s0742-8413(00)00149-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aim of the present study was to determine whether short-term administration of hexachlorobenzene (HCB) (1 g/kg body wt., suspended in water, 5 days/week), could cause and maintain marked porphyria in the absence of the exogenous drug, and whether porphyria parameters can be useful as biomarkers of HCB persistence in rats. Hepatic uroporphyrinogen decarboxylase activity, its inhibitor formation, porphyrin content and composition were studied in Wistar rats treated with the fungicide for 1, 2, 3, or 4 weeks and then withdrawn for a 20-week period. The time course of urinary porphyrin excretion was studied for 7 weeks either by continuous treatment for the entire period, or a 1-week HCB administration. The degree of porphyria achieved by rats after 20 weeks of suspended HCB administration was severe, independent of the length of the treatment, and even higher than that observed in animals analysed immediately at the end of each treatment. Rats treated with HCB for 1 week showed a modest decrease in uroporphyrinogen decarboxylase and low inhibitor formation, and exhibited a greater enzyme inhibition, inhibitor formation, hepatic porphyrin accumulation, and an altered pattern of porphyrin composition in the absence of the exogenous drug. Independent of the treatment, urinary porphyrins rose after a delay of 5 weeks. Substantial amounts of HCB were still found in fat of rats treated with HCB for 1 week, after a withdrawal period of 20 weeks. These results suggest that the high persistence of HCB in tissues acts as a continuous source of the xenobiotic, and stimulus for heme biosynthesis derangement. The alterations induced by HCB within 1 week of treatment could be regarded as an initial trigger for irreversible damage on heme metabolism. Thus, abnormalities in heme biosynthesis can be considered effective markers of HCB persistence in rats or of irreversible HCB-induced damage. Taking into account the delayed and enhanced metabolic effects of HCB, it is advisable that porphyria parameters should be evaluated not only immediately after exposure, but also some time afterwards, especially in susceptible and occupationally-exposed populations.
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Billi de Catabbi SC, Setton-Advruj CP, Sterin-Speziale N, San Martín de Viale LC, Cochón AC. Hexachlorobenzene-induced alterations on neutral and acidic sphingomyelinases and serine palmitoyltransferase activities. A time course study in two strains of rats. Toxicology 2000; 149:89-100. [PMID: 10967406 DOI: 10.1016/s0300-483x(00)00234-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hexachlorobenzene (HCB) induces porphyria both in humans and rodents, and hepatocarcinoma in rodents. In a previous work we observed that HCB produces a continuous decrease in hepatic sphingomyelin (SM) content in Wistar rats. A distinguishing characteristic of sphingolipids breakdown products is their participation in anti-proliferative and apoptotic processes and in the suppression of oncogenesis. As a first step to elucidate the role of SM decrease in the hepatotoxicity induced by HCB, the present study evaluates the metabolic causes of the continuous decrease in hepatic SM content observed in Wistar rats with HCB intoxication, and its relation with porphyria development. For this purpose, the time-course (3, 7, 15, 21 and 28 days) of the effects of HCB on hepatic SM levels and on some of the enzymes of SM synthesis (serine palmitoyltransferase, SPT) and catabolism (sphingomyelinases, SMases) was followed, using two strains of rats differing in their susceptibility to acquire porphyria: Chbb THOM (low) and Wistar (high). HCB (1 g kg(-1) b.w. per day) was administered by gastric intubation as an aqueous suspension. After 5 days of HCB treatment, animals were allowed a 2-day recovery period without HCB administration. Two phases in the HCB-induced damages to sphingolipid metabolism were observed. The first stage (7 days of treatment), common to both strains of rats, was characterized by a decrease in hepatic SM levels (17-25%) and in SPT activity (50-43%), while strain differences were found for the later stage. In Chbb THOM rats, hepatic SM content was restored to normal values concomitantly with an increase in SPT activity (44%, at day 28), and without any increase in SM catabolism. In addition, the level of the other phospholipids was not altered. In Wistar rats, hepatic SM levels decreased continuously throughout the experiment, accompanied by increases in SPT, acidic sphingomyelinase (A-SMase) and neutral sphingomyelinase (N-SMase) activities (86, 28.5 and 78% increase, respectively). A role for glutathione (GSH) in the interstrain differences or a direct effect of HCB on SM metabolism was not found. The present study: (a) demonstrates that N-SMase, A-SMase, and SPT are some of the enzymes that play a role in the HCB-induced decrease of hepatic SM content; (b) finds that HCB-induced alterations of SM metabolism do not correlate with HCB-induced accumulation of hepatic porphyrins; and (c) proposes a link between HCB-induced alterations in phospholipid pattern and in SM metabolism. The increased SM hydrolysis produced as a consequence of SMases induction could be regarded as a cellular response to liver injury elicited by HCB, perhaps acting through the activation of SM signal transduction pathway delaying the proliferative processes observed after long-term treatment with HCB in some rodent species. However, such protective mechanism appears to be strain-dependent.
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Affiliation(s)
- S C Billi de Catabbi
- Departamento de Química Biológica, Laboratorio de Porfirias Experimentales y Metabolismo del Hemo, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. II. 4to piso, 1428 Buenos Aires, Argentina
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Cochón AC, San Martín de Viale LC, Billi de Catabbi SC. Effects of hexachlorobenzene on phospholipid and porphyrin metabolism in Harderian glands: a time-course study in two strains of rats. Toxicol Lett 1999; 106:129-36. [PMID: 10403656 DOI: 10.1016/s0378-4274(99)00015-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hexachlorobenzene, one of the most persistent environmental pollutants, induces uroporphyria and phospholipid alterations in rat liver. Harderian glands produce a secretion that is rich in lipids and accumulate large amounts of protoporphyrin. The aim of the present study was to determine if hexachlorobenzene administration to rats affects phospholipid and porphyrin metabolisms in Harderian glands and if these effects are strain dependent. For this purpose, a time-course study (2, 3 and 4 weeks of hexachlorobenzene treatment) of phospholipid pattern and porphyrin content was performed comparatively in two strains of rats (Wistar and Chbb THOM) which differ in their susceptibility to develop HCB-induced porphyria. Hexachlorobenzene produced decreases in several phospholipid contents, but no changes in phosphatidylcholine levels. While the sphingomyelin/phosphatidylcholine molar ratio remained essentially constant until the third week in Chbb THOM rats, it showed a constant drop in Wistar rats, suggesting a more pronounced alteration of membrane fluidity in the later strain. In regard to porphyrin metabolism, Wistar rats showed an increase in the porphyrin content of the gland, while Chbb THOM animals showed a decrease. The study revealed that not only are the normal parameters of phospholipid and porphyrin metabolism in rat Harderian glands strain dependent, but the response to hexachlorobenzene is also.
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Affiliation(s)
- A C Cochón
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Argentina
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Hendriks AJ. Modelling non-equilibrium concentrations of microcontaminants in organisms: comparative kinetics as a function of species size and octanol-water partitioning. CHEMOSPHERE 1995; 30:265-292. [PMID: 7874474 DOI: 10.1016/0045-6535(94)00389-c] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
From our experience, risk assessment for environmental management and research purposes is in need of models that apply to many of the species we want to protect from many of the microcontaminants released. The traditional one-compartment model serves as such a tool during interpretation and extrapolation of information on concentration kinetics. Unfortunately, its non-steady parameters are specific for a combination of a compound and a species. So, one must seriously face the prospect that their values will never be measured for most compounds and species due to experimental, ethical and financial constraints. It was therefore considered worthwhile to relate the main non-steady state parameter, viz. the outflow (elimination, clearance, depuration) rate, to common characteristics of compounds and species. The outflow rate (kout) for persistent organic microcontaminants was correlated to the octanol-water partition ratio of the compound (Kow) and the size of the species (z). The regressions for aquatic invertebrates, fish and warm-blooded animals were kout = (1/(4*10(-3)*Kow + 7*10(-8)) + 5*10(-3))*z-0.36 (n = 53, r2 = 0.45), kout = (1/(4*10(-4)*Kow + 5) + 4*10(-3))*z-0.19 (n = 140, r2 = 0.68) and kout = (1/(3*10(-4)*Kow + 2*10(-5)) + 8*10(-3))* z-0.86 (n = 51, r2 = 0.48) respectively. The correlation was less strong if Kow or z were omitted. In addition to the minimum loss rate for persistent compounds, one may distinguish an excess outflow rate (mainly caused by biotransformation) for less persistent organic microcontaminants. The order of magnitude difference is explored and ways to refine these estimations are discussed briefly. Outflow rates for cadmium and mercury are linked to species size with the same type of function. The internal consistency of the model was verified by calculating inflow rates from calibrated outflow rates and comparing these to independent measurements. Moreover, the constants in the regressions are explained physically and their value is compared with those obtained in ecology for consumption, production and respiration. The exponent that scales these rates to the species size is similar to the regressions for outflow rates obtained here. The model allows estimations for fairly unknown substances or species and it is thought to help refining risk evaluations without extensive experimental or desk studies. As this paper shows that joint application of chemical (Kow) and ecological (z) information yields more accurate estimations, this study contributes to the often advocated integration of both disciplines in ecotoxicology.
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Affiliation(s)
- A J Hendriks
- Institute for Inland Water Management and Waste Water Treatment, Lelystad, The Netherlands
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Appendix F: Chlorinated benzenes. Regul Toxicol Pharmacol 1994. [DOI: 10.1016/s0273-2300(05)80031-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Roth WL, Freeman RA, Wilson AG. A physiologically based model for gastrointestinal absorption and excretion of chemicals carried by lipids. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 1993; 13:531-543. [PMID: 8259443 DOI: 10.1111/j.1539-6924.1993.tb00012.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Pharmacokinetic models which incorporate independently measured anatomical characteristics and physiological flows have been widely used to predict the pharmacokinetic behavior of drugs, anesthetics, and other chemicals. Models appearing in the literature have included as many as 18, or as few as 5 tissue compartments. With the exception of the multiple-compartment delay trains used by Bischoff to model the delays inherent to the appearance of drug metabolites in bile and segments of the intestinal lumen, very little effort has been made to incorporate the available information on gastrointestinal anatomy and physiology into more accurate gastrointestinal absorption/enterohepatic recirculation submodels. Since several authors have shown that the lymphatic system is the most significant route of absorption for highly lipophilic chemicals, we have constructed a model of gastrointestinal absorption that emphasizes chylomicron production and transport as the most significant route of absorption for nonvolatile, lipophilic chemicals. The absorption and distribution of hexachlorobenzene after intravenous vs. oral dosing are used to demonstrate features of this model.
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Affiliation(s)
- W L Roth
- Monsanto Company, Environmental Health Laboratory, St. Louis, Missouri
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To-Figueras J, Gómez-Catalán J, Rodamilans M, Corbella J. Mobilization of stored hexachlorobenzene and p,p-dichlorodiphenyldichloroethylene during partial starvation in rats. Toxicol Lett 1988; 42:79-86. [PMID: 3388450 DOI: 10.1016/0378-4274(88)90105-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Hexachlorobenzene (HCB) and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) kinetics were compared in rats before, during and after partial starvation. Food restriction produced a drastic mobilization of the residues stored in the adipose tissue resulting in symptoms of neurotoxicity. The redistribution was reversible and did not produce a significant reduction in the chemicals body burden. HCB and p,p'-DDE, although both highly lipophilic, showed important differences in their blood transport and distribution pattern, with more HCB being transported by red blood cells and with a greater facility for HCB to reach the liver and the brain.
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Affiliation(s)
- J To-Figueras
- Department of Toxicology, Hospital Clínic, Facultat de Medicina, Universitat de Barcelona, Spain
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Abstract
Sixty rats were divided into two groups; one group received normal Rat Chow and the other the same feed supplemented with 5% hexadecane. Twenty-four hours later, the rats were injected iv with 1.0 mg/kg [14C]hexachlorobenzene (HCB). For 1 month after dosing, the activity of 14C was determined in various tissues and in serum at predetermined intervals. A biexponential decline of radioactivity was observed in serum and tissues of both groups; the decline of 14C in tissues roughly paralleled the decline of radioactivity in serum; exceptions were fat, skin, and the contents of the large intestine, which showed an initial uptake phase. Hexadecane increased the disposition rate constant beta in serum, leading to a significantly reduced body burden after 4 weeks of treatment. The more rapid loss of tissue radioactivity was accompanied by increased levels of 14C in intestinal contents of the large intestine. Biliary excretion was unaffected. Data are compatible with describing the kinetics of HCB by a two-compartment open model, where elimination occurs from a part of the peripheral compartment.
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Bleavins MR, Aulerich RJ, Ringer RK. Effects of chronic dietary hexachlorobenzene exposure on the reproductive performance and survivability of mink and European ferrets. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1984; 13:357-365. [PMID: 6742893 DOI: 10.1007/bf01055287] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Gopalaswamy UV, Aiyar AS. Biotransformation of lindane in the rat. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1984; 32:148-156. [PMID: 6200164 DOI: 10.1007/bf01607478] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Breslin WJ, Bleavins MR, Ringer RK. Distribution and excretion of hexachlorobenzene in bobwhite (Colinus virginianus). JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1983; 11:885-96. [PMID: 6620419 DOI: 10.1080/15287398309530392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
After a single dose of [14C]hexachlorobenzene (HCB) via gavage into the crop, the accumulation of [14C]HCB in female bobwhite (Colinus virginianus) tissues occurred to the greatest extent in adipose tissue followed by skin, liver, brain, heart and kidney, whole blood, and muscle. There was a general relation between increasing HCB concentration and increasing fat content of the tissue. Absorption of [14C]-HCB was rapid with peak radioactivity occurring at 4 h in all tissues except for fat and skin, where it continued to rise until 32 and 16 h after dosing, respectively. Elimination of HCB from tissue was biphasic with phase I representing the combination of HCB excretion and HCB redistribution from tissue into fat stores. Phase II represented solely HCB excretion, which appeared to be a first-order process. The half-life of [14C]HCB in tissues, feces, and eggs ranged from 9-13 d regardless of HCB concentration. Radioactive HCB accumulation in egg yolk was a significant mechanism for the removal of this chemical from bobwhite and accounted for 50% of the total HCB excreted.
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Koss G, Seubert S, Seubert A, Seidel J, Koransky W, Ippen H. Studies on the toxicology of hexachlorobenzene. V. Different phases of porphyria during and after treatment. Arch Toxicol 1983; 52:13-22. [PMID: 6838374 DOI: 10.1007/bf00317978] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Bleavins MR, Breslin WJ, Aulerich RJ, Ringer RK. Excretion and placental and mammary transfer of hexachlorobenzene in the European ferret (Mustela putorius furo). JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1982; 10:929-40. [PMID: 7161840 DOI: 10.1080/15287398209530307] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Female European ferrets (Mustela putorius furo) absorbed 98.5% of a single dietary exposure of hexachlorobenzene (HCB). The HCB was found to readily cross the placenta and to be excreted in the milk of pregnant/lactating ferrets. After consuming HCB-treated feed, ferrets raising offspring excreted 50% of the initial dose by 32 d, while unbred ferrets achieved this same degree of HCB elimination in 41 d. The percentages of HCB excreted via the urine and feces were approximately 5 and 45%, respectively, in both groups at the 50% stage of elimination. Adipose tissue was the most significant long-term repository for HCB in the ferret. The other tissues analyzed for [14C]HCB showed a general relationship of increased radioactivity with increased fat content of the tissue. The ferrets with nursing kits were able to significantly reduce their body burden of HCB when compared to unbred females. The developing ferret kits were subjected to HCB insult both in utero and via dam's milk. The ratio of milk to placental exposure in the growing offspring was calculated to be 31:1. Thus, in addition to any toxic effects HCB may have on the adult reproducing population, the placental and mammary transfer of HCB constitutes a potential threat to the developing and growing animal.
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Debets F, Reinders JH, Koss G, Seidel J, Strik A. Effects of dietary antioxidants on the biotransformation and porphyrinogenic action of hexachlorobenzene in two strains of rats. Chem Biol Interact 1981; 37:77-94. [PMID: 7285248 DOI: 10.1016/0009-2797(81)90167-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Abstract
This overview of the metabolism of the fungicides hexachlorobenzene (HCB) and pentachloronitrobenzene (PCNB) indicates similarities in their pathways of biotransformation. Several metabolites of HCB and PCNB, such as chlorinated benzenes, the mercapturic acid, thiophenols, thioanisoles and phenols are identical. Both Fungicides initially react with glutathione, with elimination or of the chlorine of the nitro group respectively. The conjugate, S-(pentachlorophenyl)glutathione, is further metabolized by cleavage of the glutamate and glycine results and acetylation of the amino group of the cysteinyl moiety, to give the mercapturic acid N-acetyl-S-(pentachlorophenyl)cysteine, a major metabolite of HCB and PCNB in rats and rabbits respectively, which is further metabolized to simpler sulphur-containing products.
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Debets FM, Reinders JH, Debets AJ, Lössbroek TG, Strik JJ, Koss G. Biotransformation and porphyringogenic action of hexachlorobenzene and its metabolites in a primary liver cell culture. Toxicology 1981; 19:185-96. [PMID: 7233443 DOI: 10.1016/0300-483x(81)90128-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Hexachlorobenzene (HCB) is metabolized in a primary culture of chick embryo liver cells and causes porphyrin accumulation within 24 h after administration. The HCB-metabolites, pentachlorothiophenol (PCThP), pentachlorobenzene (PeCB) and pentachlorophenol (PCP) identified in liver cell culture are already known from long-term experiments with rats. The pattern of accumulated porphyrins is comparable with the pathological porphyrin pattern observed in oral feeding studies with warm blooded laboratory animals. Protein bound radioactivity was found in cell cultures treated with [14C] HCB. Addition of the monooxygenase-inhibitor piperonyl butoxide or ascorbic acid decreased the irreversible binding of 14C-metabolites. The results show that biotransformation of HCB fulfils an essential role in the onset of porphyria. Since none of the main HCB-metabolites could induce a pathological porphyrin pattern, a reactive intermediate capable of reacting with glutathione or thiol-groups of uroporphyrinogen decarboxylase (UROG-D) is believed to be responsible for the inhibition of UROG-D. The chick embryo liver cell system may be considered as a useful and sensitive system for studying the metabolism of xenobiotics in relation to their toxicity.
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Niimi AJ, Cho CY. Uptake of hexachlorobenzene (HCB) from feed by rainbow trout (Salmo gairdneri). BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1980; 24:834-839. [PMID: 7397419 DOI: 10.1007/bf01608198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Koss G, Seubert S, Seubert A, Koransky W, Kraus P, Ippen H. Conversion products of hexachlorobenzene and their role in the disturbance of the porphyrin pathway in rats. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1980; 12:1003-6. [PMID: 7450109 DOI: 10.1016/0020-711x(80)90202-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Bickel MH, Muehlebach S. Pharmacokinetics and ecodisposition of polyhalogenated hydrocarbons: aspects and concepts. Drug Metab Rev 1980; 11:149-90. [PMID: 6783377 DOI: 10.3109/03602538008994024] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Dunn JS, Bush PB, Booth NH, Farrell RL, Thomason DM, Goetsch DD. Effect of pentachloronitrobenzene upon egg production, hatchability, and residue accumulation in the tissues of White Leghorn hens. Toxicol Appl Pharmacol 1979; 48:425-33. [PMID: 473189 DOI: 10.1016/0041-008x(79)90426-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Koss G, Koransky W, Steinbach K. Studies on the toxicology of hexachlorobenzene. IV. Sulphur-containing metabolites. Arch Toxicol 1979; 42:19-31. [PMID: 454182 DOI: 10.1007/bf00351821] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
After administration of hexachlorobenzene rats excrete sulphur-containing conjugates from which pentachlorothiophenol can be split off. In the present study we describe the identification of pentachlorothiophenol and pentachlorothioanisol in the livers of animals treated with hexachlorobenzene. In order to clarify the further fate of these two substances, we administered them to rats, and isolated the conversion products excreted in the urine and feces. The metabolites of pentachlorothiophenol and pentachlorothioanisol are excreted in both conjugated and free form. From extracts of the excreta, we isolated tetra- and trichlorobenzene with two or three sulphur-containing substituents on the ring, analogous compounds in which thiol groups were converted into sulphoxide and sulphone groups, as well as analogous compounds with a phenolic oxygen in addition to sulphur, and sulphur-containing compounds in which clorine was replaced by hydrogen. Following administration of the sulphoxide and of the sulphone of pentachlorothioanisol under analogous conditions, pentachlorothiophenol and pentachlorothioanisol and their metabolites were detected in the excreta of the animals. No evidence was obtained that the parent compounds are excreted in the unchanged form.
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36
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Allen JR, Hargraves WA, Hsia MT, Lin FS. Comparative toxicology of chlorinated compounds on mammalian species. Pharmacol Ther 1979; 7:513-47. [PMID: 93291 DOI: 10.1016/0163-7258(79)90041-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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37
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Koss G, Seubert S, Seubert A, Koransky W, Ippen H. Studies on the toxicology of hexachlorobenzene. III. Observations in a long-term experiment. Arch Toxicol 1978; 40:285-94. [PMID: 581261 DOI: 10.1007/bf00310334] [Citation(s) in RCA: 41] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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38
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Laska AL, Bartell CK, Condie DB, Brown JW, Evans RL, Laseter JL. Acute and chronic effects of hexachlorobenzene and hexachlorobutadiene in red swamp crayfish (Procambarus clarki) and selected fish species. Toxicol Appl Pharmacol 1978; 43:1-12. [PMID: 625754 DOI: 10.1016/s0041-008x(78)80027-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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den Tonkelaar EM, Verschuuren HG, Bankovska J, de Vries T, Kroes R, van Esch GJ. Hexachlorobenzene toxicity in pigs. Toxicol Appl Pharmacol 1978; 43:137-45. [PMID: 625756 DOI: 10.1016/s0041-008x(78)80038-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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40
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Renner G, Schuster KP. 2,4,5-trichlorophenol, a new urinary metabolite of hexachlorobenzene. Toxicol Appl Pharmacol 1977; 39:355-6. [PMID: 847760 DOI: 10.1016/0041-008x(77)90168-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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41
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Koss G, Koransky W, Steinbach K. Studies on the toxicology of hexachlorobenzene. II. Identification and determination of metabolites. Arch Toxicol 1976; 35:107-14. [PMID: 947309 DOI: 10.1007/bf00372764] [Citation(s) in RCA: 87] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Female rats were dosed intraperitoneally with 14C-hexaxhlorobenzene. The drug was administered on 2 or 3 occasions. The total doses amounted to 260 and 390 mg/kg 14C-hexachlorobenzene, respectively. Urine and feces from the animals were collected over a period of 4 weeks after the first injection. Both excreta and some tissues of the animals were examined for their content of radioactivity and for hexachlorobenzene and its metabolites. Gas chromatography, isotope dilution analysis, and combined gas chromatography-mass spectrometry were used to identify the metabolites of hexachlorobenzene. In urine pentachlorophenol, tetrachlorohydroquinone, and pentachlorothiophenol were present as major metabolites. One of the isomers of tetrachlorothiophenol was present as a minor metabolite. In the feces pentachlorophenol and pentachlorothiophenol only were identified. At the end of the experiment, carbon-14 excreted with urine and feces amounted to 7% and 27%, respectively, of the radioactivity administered. More than 90% of carbon-14 excreted in urine was contained in the major metabolites. In the feces about 30% of the excreted radioactivity was bound to metabolites and about 70% was contained in the unchanged drug, while in the tissues of the animals only pentachlorophenol was detected in measurable amounts, accounting for 10% of label in blood and less than 0.1% of carbon-14 determined in body fat. Total radioactivity contained in the metabolites detected in the animal body and in the excreta at the end of the experiment accounted for about 16% of the administered radioactivity.
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