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Li Z. Spatiotemporal pattern models for bioaccumulation of pesticides in herbivores: An approximation theory for North American white-tailed deer. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 737:140271. [PMID: 32783856 DOI: 10.1016/j.scitotenv.2020.140271] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 06/10/2020] [Accepted: 06/14/2020] [Indexed: 06/11/2023]
Abstract
Dietary exposure is a major cause of pesticide bioaccumulation in herbivores. However, various types of natural conditions affect the structure of the complicated herbivores' diets, making it difficult to assess their exposure to pesticides. In this study, to evaluate the role of pesticides in the terrestrial food web, a dynamic hybrid dietary model was developed for North American white-tailed deer (or whitetails), which integrates different plant types and the digestibility of deer's foods. Moreover, an equivalent season approach was introduced to generalize the pesticide intake rate geographically. The results indicate that the soil-to-whitetail (meat) bioaccumulation factor (BAF) values in summer are significantly higher than those of other seasonal periods, owing to the high food availability and digestibility. Pesticides with low octanol/water partition coefficients have a high computed soil-to-plant BAF, but a low plant-to-whitetail (meat) BAF, because the transpiration process dominates the bioaccumulation process in plants. Lipid absorption plays a more important role in herbivores and lowers the biomagnification ratio (a smaller amount of pesticides flows to the next level of the food chain). According to the equivalent season approach, geographic locations with warmer climates facilitate pesticide bioaccumulation at a higher level of the terrestrial food web.
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Affiliation(s)
- Zijian Li
- School of Public Health (Shenzhen), Sun Yat-sen University, Guangdong 510275, China.
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2
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Di S, Liu R, Chen L, Diao J, Zhou Z. Selective bioaccumulation, biomagnification, and dissipation of hexachlorocyclohexane isomers in a freshwater food chain. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:18752-18761. [PMID: 29713971 DOI: 10.1007/s11356-018-2044-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 04/16/2018] [Indexed: 06/08/2023]
Abstract
Hexachlorocyclohexane isomers (HCHs) are persistent organic pollutants (POPs), having potential risks to humans and ecosystem. This work evaluated the propensity of organisms to accumulate, eliminate, and transfer HCHs along the food chain (Tubifex tubifex and common carp (Cyprinus carpio)). The accumulation of HCHs from water by worms and carp was observed, and the concentrations increased with exposure time. After 8 days, the HCH concentrations in organisms remained stable. The accumulation factor (AF) values of HCHs in T. tubifex were higher than those in carp, indicating that the bioaccumulation abilities of HCHs in T. tubifex were higher than those in carp. The contaminated worms as a dietary source in the food chain led to significantly higher bioaccumulation in carp. The biomagnification factor (BMF) values of HCH isomers were all greater than 1. In the dissipation experiments, the elimination was fast and the half-lives were shorter than 2.5 days. The enantioselective accumulation and dissipation of α-HCH enantiomers were observed in worms and carp (food chain), and the enantiomeric differences should be taken into consideration in the study of contaminants risk assessment. The results on trophic transfer of HCHs in a freshwater food chain should be helpful for better understanding the fate, transport, and transfer of HCHs in freshwater environments.
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Affiliation(s)
- Shanshan Di
- Institute of Quality and Standard of Agro-Products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
- Agricultural Ministry Key Laboratory for Pesticide Residue Detection, Hangzhou, 310021, China
- Key Laboratory of Detection for Pesticide Residues and Control of Zhejiang, Hangzhou, 310021, China
| | - Ruiquan Liu
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China
| | - Li Chen
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, Yuanmingyuan west road 2, Beijing, 100193, People's Republic of China
| | - Jinling Diao
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China
| | - Zhiqiang Zhou
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China.
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, Yuanmingyuan west road 2, Beijing, 100193, People's Republic of China.
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3
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de Gelder S, Sundh H, Pelgrim TNM, Rasinger JD, van Daal L, Flik G, Berntssen MHG, Klaren PHM. Transepithelial transfer of phenanthrene, but not of benzo[a]pyrene, is inhibited by fatty acids in the proximal intestine of rainbow trout (Oncorhynchus mykiss). Comp Biochem Physiol C Toxicol Pharmacol 2018; 204:97-105. [PMID: 29223736 DOI: 10.1016/j.cbpc.2017.11.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 11/20/2017] [Accepted: 11/21/2017] [Indexed: 11/20/2022]
Abstract
The inclusion of vegetable oils in aquafeeds introduces contaminating polycyclic aromatic hydrocarbons (PAHs) in salmonids. Since lipophilic PAHs solubilize in micelles composed of lipids, bile salts and fatty acids, dietary lipid composition can alter intestinal transepithelial PAH transfer. We studied the uptake of two PAHs, viz. benzo[a]pyrene (BaP) and phenanthrene (PHE), in rainbow trout (Oncorhynchus mykiss) intestine. We also investigated the effects of two fatty acids, viz. fish oil-derived eicosapentaenoic acid (EPA, 20:5n-3) and vegetable oil-derived oleic acid (18:1n-9) on intestinal uptake. Radiolabeled PAHs were solubilized in micelles composed of tritiated EPA and oleic acid, respectively, and administrated to intestinal segments mounted in Ussing chambers. In the absence of micelles, PHE accumulation was two times higher than BaP in the mucosal and serosal layers of proximal and distal intestine. Administration of PHE in micelles composed of oleic acid resulted in a 50% lower accumulation of PHE in the mucosal layers of the proximal intestine compared to EPA-composed micelles. Accumulation of EPA and oleic acid in the proximal intestinal mucosa correlated negatively with the transepithelial transfer of these fatty acids across the proximal intestinal epithelium. Transepithelial PHE transfer across the proximal intestine was reduced by 30% in co-exposure with EPA-composed micelles compared to 80% with oleic acid micelles. BaP was not transferred across the intestine. We conclude that the lipid composition of an aquafeed is an important determinant of PAH bioavailability. Therefore, lipid composition should be an important consideration in choosing vegetable oils as alternatives for fish oil in aquafeeds.
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Affiliation(s)
- Stefan de Gelder
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands; National Institute of Nutrition and Seafood Research, P.O. Box 2029, Nordnes, 5817 Bergen, Norway
| | - Henrik Sundh
- Fish Endocrinology Laboratory, Department of Biological and Environmental Sciences, University of Gothenburg, Box 463, 40530 Gothenburg, Sweden
| | - Thamar N M Pelgrim
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Josef D Rasinger
- National Institute of Nutrition and Seafood Research, P.O. Box 2029, Nordnes, 5817 Bergen, Norway
| | - Lotte van Daal
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Gert Flik
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Marc H G Berntssen
- National Institute of Nutrition and Seafood Research, P.O. Box 2029, Nordnes, 5817 Bergen, Norway
| | - Peter H M Klaren
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands.
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4
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de Gelder S, Sæle Ø, de Veen BTH, Vos J, Flik G, Berntssen MHG, Klaren PHM. The polycyclic aromatic hydrocarbons benzo[a]pyrene and phenanthrene inhibit intestinal lipase activity in rainbow trout (Oncorhynchus mykiss). Comp Biochem Physiol C Toxicol Pharmacol 2017; 198:1-8. [PMID: 28476648 DOI: 10.1016/j.cbpc.2017.04.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 04/18/2017] [Accepted: 04/25/2017] [Indexed: 11/26/2022]
Abstract
Elevated levels of polycyclic aromatic hydrocarbons (PAHs) are detected in aquafeeds where fish oils are (partially) replaced by vegetable oils. The highly lipophilic PAHs solubilize readily in oil droplets and micelles in the intestinal lumen that can affect enzymatic lipid digestion by altering lipase activity. We therefore investigated the effect of two PAHs, benzo[a]pyrene (BaP) and phenanthrene (PHE), on bile salt-activated lipase (BAL) activity in desalted luminal extracts of the proximal intestine of rainbow trout (Oncorhynchus mykiss) using the triacylglycerides rapeseed oil and fish oil as substrates. The hydrolysis of rapeseed oil and fish oil measured at a calculated substrate concentration of 2.2mM, increased linearly up to 30min at 15°C. Substrate dependency under initial velocity conditions was described by simple Michaelis-Menten kinetics with a Km value of 1.2mM for rapeseed and fish oil. Rapeseed oil hydrolysis was inhibited by 1nM BaP and 10nM PHE. The hydrolysis of fish oil was only inhibited by 10μM BaP. The in vitro lipase activity data were corroborated by TLC/HPLC analysis of the reaction products, showing that in the presence of BaP and PHE, 46-80% less free fatty acids (FFA) were hydrolysed from rapeseed and fish oil triacylglycerides. The presence of low concentrations of BaP and PHE decreased rapeseed oil hydrolysis by BAL whereas fish oil hydrolysis was not affected. The replacement of fish oil by rapeseed oil in aquafeeds introduces PAHs that could affect lipid digestion.
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Affiliation(s)
- Stefan de Gelder
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands; National Institute of Nutrition and Seafood Research, P.O. Box 2029, Nordnes, 5817 Bergen, Norway.
| | - Øystein Sæle
- National Institute of Nutrition and Seafood Research, P.O. Box 2029, Nordnes, 5817 Bergen, Norway
| | - Bas T H de Veen
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Joëlle Vos
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Gert Flik
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Marc H G Berntssen
- National Institute of Nutrition and Seafood Research, P.O. Box 2029, Nordnes, 5817 Bergen, Norway
| | - Peter H M Klaren
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
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5
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de Gelder S, van Och L, Zethof J, Pelgrim TNM, Rasinger JD, Flik G, Berntssen MHG, Klaren PHM. Uptake of benzo[a]pyrene, but not of phenanthrene, is inhibited by fatty acids in intestinal brush border membrane vesicles of rainbow trout (Oncorhynchus mykiss). Comp Biochem Physiol C Toxicol Pharmacol 2017; 195:1-8. [PMID: 28216010 DOI: 10.1016/j.cbpc.2017.02.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 02/07/2017] [Accepted: 02/09/2017] [Indexed: 12/31/2022]
Abstract
Partial replacement of fish ingredients with vegetable ingredients has elevated levels of polycyclic aromatic hydrocarbons (PAHs) in Atlantic salmon reared on these feeds. PAH uptake in the intestinal tract is postulated to occur in association with lipid absorption and could well be affected by fatty acid composition. We therefore investigated the effects of a fish oil and vegetable oil fatty acid, eicosapentaenoic acid (EPA; 20:5n-3) and oleic acid (18:1n-9) respectively, on the uptake of benzo[a]pyrene (BaP) and phenanthrene (PHE) across the intestinal brush border membrane in the salmonid species rainbow trout (Oncorhynchus mykiss). BaP and PHE were solubilized in mixed micelles composed of either EPA or oleic acid and administrated to isolated brush border membrane vesicles (BBMV) derived from the pyloric caeca, proximal intestine and distal intestine. In the absence of free fatty acids (FFA) trans-membrane uptake of BaP and PHE was 2-7 times lower than the fraction associated to or in the membrane. In the presence of FFA, trans-membrane BaP uptake had decreased by 80 and 40% at the highest EPA and oleic acid concentration, respectively, whereas PHE uptake was virtually unaffected. In the presence of BaP, but not PHE, trans-membrane EPA uptake in BBMV had decreased. This study obtained evidence for PAH-dependent interactions with FFA uptake. We conclude that intestinal BaP uptake is reduced by luminal FFA contents whereas PHE uptake is not. A large fraction of the administrated BaP and PHE remains associated with the cellular membrane of enterocytes and may interfere with uptake of nutrients.
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Affiliation(s)
- Stefan de Gelder
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands; National Institute of Nutrition and Seafood Research, P.O. Box 2029, Nordnes, 5817 Bergen, Norway.
| | - Liselot van Och
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Jan Zethof
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Thamar N M Pelgrim
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Josef D Rasinger
- National Institute of Nutrition and Seafood Research, P.O. Box 2029, Nordnes, 5817 Bergen, Norway
| | - Gert Flik
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Marc H G Berntssen
- National Institute of Nutrition and Seafood Research, P.O. Box 2029, Nordnes, 5817 Bergen, Norway
| | - Peter H M Klaren
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
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6
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Lo JC, Letinski DJ, Parkerton TF, Campbell DA, Gobas FAPC. In Vivo Biotransformation Rates of Organic Chemicals in Fish: Relationship with Bioconcentration and Biomagnification Factors. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:13299-13308. [PMID: 27993034 DOI: 10.1021/acs.est.6b03602] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In vivo dietary bioaccumulation experiments for 85 hydrophobic organic substances were conducted to derive the in vivo gastrointestinal biotransformation rates, somatic biotransformation rates, bioconcentration factors (BCF), and biomagnification factors (BMF) for improving methods for bioaccumulation assessment and to develop an in vivo biotransformation rate database for QSAR development and in vitro to in vivo biotransformation rate extrapolation. The capacity of chemicals to be biotransformed in fish was found to be highly dependent on the route of exposure. Somatic biotransformation was the dominant pathway for most chemicals absorbed via the respiratory route. Intestinal biotransformation was the dominant metabolic pathway for most chemicals absorbed via the diet. For substances not biotransformed or transformed exclusively in the body of the fish, the BCF and BMF appeared to be closely correlated. For substances subject to intestinal biotransformation, the same correlation did not apply. We conclude that intestinal biotransformation and bioavailability in water can modulate the relationship between the BCF and BMF. This study also supports a fairly simple rule of thumb that may be useful in the interpretation of dietary bioaccumulation tests; i.e., chemicals with a BMFL of <1 tend to exhibit BCFs based on either the freely dissolved (BCFWW,fd) or the total concentration (BCFWW,t) of the chemical in the water that is less than 5000.
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Affiliation(s)
- Justin C Lo
- Department of Biological Sciences, Simon Fraser University , Burnaby, British Columbia V5A 1S6, Canada
| | - Daniel J Letinski
- ExxonMobil Biomedical Sciences, Inc. , Annandale, New Jersey 08801, United States
| | - Thomas F Parkerton
- ExxonMobil Biomedical Sciences, Inc. , Spring, Texas 77339, United States
| | - Dave A Campbell
- Department of Statistics and Actuarial Science, Simon Fraser University , Surrey, British Columbia V5A 1S6, Canada
| | - Frank A P C Gobas
- Department of Biological Sciences, Simon Fraser University , Burnaby, British Columbia V5A 1S6, Canada
- School of Resource and Environmental Management, Faculty of the Environment, Simon Fraser University , Burnaby, British Columbia V5A 1S6, Canada
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7
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de Gelder S, Bakke MJ, Vos J, Rasinger JD, Ingebrigtsen K, Grung M, Ruus A, Flik G, Klaren PHM, Berntssen MHG. The effect of dietary lipid composition on the intestinal uptake and tissue distribution of benzo[a]pyrene and phenanthrene in Atlantic salmon (Salmo salar). Comp Biochem Physiol C Toxicol Pharmacol 2016; 185-186:65-76. [PMID: 26972757 DOI: 10.1016/j.cbpc.2016.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 03/02/2016] [Accepted: 03/09/2016] [Indexed: 01/28/2023]
Abstract
Uptake of polycyclic aromatic hydrocarbons (PAHs) across the intestine is suggested to occur in association with dietary lipids. Partial replacement of fish ingredients by vegetable ingredients in aquafeeds has led to increased levels of PAHs in marine farmed fish. We therefore investigated, intestinal uptake, tissue distribution and PAH metabolism after a single dose of (14)C-benzo[a]pyrene (BaP) or (14)C-phenanthrene (PHE) given to Atlantic salmon (Salmo salar) acclimatized to a fish oil or vegetable oil based diet. Both BaP and PHE were absorbed along the intestine. Fish oil based feed increased BaP concentration in the pyloric caeca and that of PHE in the proximal intestine. In contrast, vegetable oil increased BaP concentrations in the distal intestine. Extraction of whole body autoradiograms removed PHE-associated radiolabeling almost completely from the intestinal mucosa, but not BaP-associated radiolabeling, indicating the presence of BaP metabolites bound to cellular macromolecules. This observation correlates with the increased cyp1a expression in the proximal intestine, distal intestine and liver in the BaP exposed group. Furthermore, BaP-induced cyp1a expression was higher in the distal intestine of salmon fed fish oil compared to the vegetable oil fed group. PHE had no significant effect on cyp1a expression in any of these tissues. We conclude that dietary lipid composition affects intestinal PAH uptake. Fish oil based feed increased intestinal PAH concentrations probably due to an enhanced solubility in micelles composed of fish oil fatty acids. Increased BaP accumulation in the distal intestine of vegetable oil fed fish seems to be associated with a reduced Cyp1a-mediated BaP metabolism.
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Affiliation(s)
- Stefan de Gelder
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands; National Institute of Nutrition and Seafood Research, P.O. Box 2029 Nordnes, 5817 Bergen, Norway.
| | - Marit J Bakke
- University of Life Science (NMBU), Faculty of Veterinary Medicine and Biosciences, Department of Food Safety and Infection Biology, P.O. Box 8146 Dep., 0033 Oslo, Norway
| | - Joëlle Vos
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Josef D Rasinger
- National Institute of Nutrition and Seafood Research, P.O. Box 2029 Nordnes, 5817 Bergen, Norway
| | - Kristian Ingebrigtsen
- University of Life Science (NMBU), Faculty of Veterinary Medicine and Biosciences, Department of Food Safety and Infection Biology, P.O. Box 8146 Dep., 0033 Oslo, Norway
| | - Merete Grung
- Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo, Norway
| | - Anders Ruus
- Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo, Norway
| | - Gert Flik
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Peter H M Klaren
- Radboud University, Institute for Water and Wetland Research, Department of Animal Ecology and Physiology, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands
| | - Marc H G Berntssen
- National Institute of Nutrition and Seafood Research, P.O. Box 2029 Nordnes, 5817 Bergen, Norway
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8
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Comparative absorption and tissue distribution of 14C-benzo(a)pyrene and 14C-phenanthrene in the polar cod (Boreogadus saida) following oral administration. Polar Biol 2015. [DOI: 10.1007/s00300-015-1816-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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9
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Khan S, Khan S, Baboota S, Ali J. Immunosuppressive drug therapy – biopharmaceutical challenges and remedies. Expert Opin Drug Deliv 2015; 12:1333-49. [DOI: 10.1517/17425247.2015.1005072] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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10
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Cho YD, Park YJ. In vitro and in vivo evaluation of a self-microemulsifying drug delivery system for the poorly soluble drug fenofibrate. Arch Pharm Res 2013; 37:193-203. [DOI: 10.1007/s12272-013-0169-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 05/16/2013] [Accepted: 05/28/2013] [Indexed: 11/28/2022]
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11
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Yáñez JA, Wang SW, Knemeyer IW, Wirth MA, Alton KB. Intestinal lymphatic transport for drug delivery. Adv Drug Deliv Rev 2011; 63:923-42. [PMID: 21689702 PMCID: PMC7126116 DOI: 10.1016/j.addr.2011.05.019] [Citation(s) in RCA: 167] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2009] [Revised: 10/15/2010] [Accepted: 01/26/2011] [Indexed: 12/16/2022]
Abstract
Intestinal lymphatic transport has been shown to be an absorptive pathway following oral administration of lipids and an increasing number of lipophilic drugs, which once absorbed, diffuse across the intestinal enterocyte and while in transit associate with secretable enterocyte lipoproteins. The chylomicron-associated drug is then secreted from the enterocyte into the lymphatic circulation, rather than the portal circulation, thus avoiding the metabolically-active liver, but still ultimately returning to the systemic circulation. Because of this parallel and potentially alternative absorptive pathway, first-pass metabolism can be reduced while increasing lymphatic drug exposure, which opens the potential for novel therapeutic modalities and allows the implementation of lipid-based drug delivery systems. This review discusses the physiological features of the lymphatics, enterocyte uptake and metabolism, links between drug transport and lipid digestion/re-acylation, experimental model (in vivo, in vitro, and in silico) of lymphatic transport, and the design of lipid- or prodrug-based drug delivery systems for enhancing lymphatic drug transport.
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12
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Haave M, Bernhard A, Folven KI, Brattelid T, Lundebye AK. Fish consumption reduces transfer of BDE47 from dam to murine offspring. CHEMOSPHERE 2011; 84:348-354. [PMID: 21555145 DOI: 10.1016/j.chemosphere.2011.04.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 03/08/2011] [Accepted: 04/01/2011] [Indexed: 05/30/2023]
Abstract
Fish and seafood are important contributions to a healthy diet, but also contain persistent organic pollutants (POPs) like polybrominated diphenylethers (PBDEs) and polychlorinated biphenyls (PCBs). Discrepancies have been found between intake and accumulated levels of POPs, where fish consumers have had similar levels of POPs to the general population. Similarly fish oil consumption has been found to reduce accumulation of POPs. This study examined the accumulation of BDE47 or PCB153 in mice fed diets with different nutritional composition, using female mice with pre-weanling pups exposed through gestation and lactation. A fish-based diet was compared to a standard casein-based rodent diet. All diets had low background levels of environmental contaminants and were spiked with BDE47 or PCB153 to levels representing a realistic (∼0.004 μmol kg bw(-1) d) or a high dietary exposure (∼1.3 μmol kg bw(-1) d). Accumulation of BDE47 or PCB153 in offspring tissues after 18d lactation reflected the maternal exposure levels. However, the pups of dams fed a fish-based diet had consistently lower BDE47 accumulation in liver, fat and stomach than pups from casein-fed dams. Similarly the pups of dams fed a high dose of PCB153 in a fish diet also accumulated less PCB153 than pups of the dams fed a casein diet, although not significant. In conclusion, the fish based diets seemed to reduce transfer of BDE47 and PCB153 from dams to pups. The study highlights that in-depth knowledge about nutritional impact on toxicokinetics is of great interest to vulnerable consumers.
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Affiliation(s)
- Marte Haave
- National Institute of Nutrition and Seafood Research (NIFES), P.O. Box 2029 Nordnes, N-5817 Bergen, Norway.
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13
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Kobayashi J, Kinoshita K, Mizukawa K, Sakurai T, Imaizumi Y, Takada H, Suzuki N. Dietary uptake kinetics of polychlorinated biphenyls from sediment-contaminated sandworms in a marine benthic fish (Pseudopleuronectes yokohamae). CHEMOSPHERE 2011; 82:745-750. [PMID: 21126752 DOI: 10.1016/j.chemosphere.2010.10.087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 10/26/2010] [Accepted: 10/31/2010] [Indexed: 05/30/2023]
Abstract
To evaluate the dietary uptake of polychlorinated biphenyls (PCBs) from live food, we investigated the dietary uptake and depuration kinetics of PCBs in a marine benthic fish (marbled sole, Pseudopleuronectes yokohamae) by using as food live sandworms (Perinereis nuntia) that were laboratory-exposed to field-collected PCB-contaminated sediment. Marbled sole were fed the PCB-contaminated sandworms for 28d and then uncontaminated sandworms for 56d. The assimilation efficiencies (AEs) of 84 PCB congeners via the gastrointestinal tract (GIT) to the muscle of the fish ranged from 0.21 to 0.78; whole-body AEs would be lower than those of muscle because of the lower PCB concentrations, on a lipid basis. The AEs determined in this study were lower than those in other studies that used PCB-spiked commercial pelletized food. The lower AEs found in this study might be attributable to differences in the food administered (live sandworms vs. commercial pellet food), possibly because of low digestibility of sandworm lipids by marbled sole. In addition, the AEs in this study tended to increase with increasing log octanol-water partition coefficients (K(OW)) up to about seven, although AEs in the other studies using commercial pelletized food did not increase with increasing logK(OW). This result suggests the co-transport of highly hydrophobic PCB congeners along with lipids and fatty acids from the digested sandworms into the GIT epithelium cells. The growth-corrected half-lives of 26 PCB congeners in the muscle of fish ranged from 20 to 107d.
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Affiliation(s)
- Jun Kobayashi
- Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan.
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14
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Formulate-ability of ten compounds with different physicochemical profiles in SMEDDS. Eur J Pharm Sci 2009; 38:479-88. [DOI: 10.1016/j.ejps.2009.09.012] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Revised: 09/02/2009] [Accepted: 09/17/2009] [Indexed: 11/22/2022]
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15
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Harris DL, Washington MK, Hood DB, Roberts LJ, Ramesh A. Dietary fat-influenced development of colon neoplasia in Apc Min mice exposed to benzo(a)pyrene. Toxicol Pathol 2009; 37:938-46. [PMID: 19841130 PMCID: PMC2982189 DOI: 10.1177/0192623309351722] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Colorectal cancer, responsible for 50,000 deaths per year, is a contributing factor for considerable mortalities in the United States. Consumption of well-done red meat and saturated fats rich in polycyclic aromatic hydrocarbons may be one of the causative factors for sporadic colon cancer. The objective of this study was to investigate whether the formation of colon tumors in adult Apc(Min) mice was influenced by the ingestion of different types of fat containing benzo(a)pyrene [B(a)P], a polycyclic aromatic hydrocarbon compound. Treatment consisted of 50 and 100 microg B(a)P/kg body weight dissolved in peanut or coconut oil (representatives of unsaturated and saturated fats, respectively) administered daily to six-week-old male Apc(Min) mice via oral gavage for sixty days. At the end of exposure, mice were sacrificed; jejunum and colons were retrieved and preserved in 10% formalin for observation for gross pathological changes. An increased prevalence of adenomas in colons of mice that ingested B(a)P through saturated dietary fat compared to unsaturated fat and controls (p < .05) was noticed. Interestingly, we also observed adenomas with high-grade dysplasia in the B(a)P + saturated fat group, and these incidences were frequent at the 100 microg/kg B(a)P dose. On the other hand, the B(a)P-alone and unsaturated-fat groups did not show significant differences in the numbers of adenomas and invasive tumors in the both jejunum and the colon. Our studies established that dietary fat, especially saturated fat, potentiates the development of colon tumors caused by B(a)P in the Apc(Min) mouse.
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Affiliation(s)
- Deacqunita L. Harris
- Department of Biochemistry and Cancer Biology, Meharry Medical College, 1005 D. B. Todd Blvd., Nashville, TN 37208
| | - Mary K. Washington
- Department of Pathology, Vanderbilt University School of Medicine, 1161 21st Ave. S., Nashville, TN 37232
| | - Darryl B. Hood
- Department of Neuroscience and Pharmacology, Meharry Medical College, 1005 D. B. Todd Blvd., Nashville, TN 37208
| | - L. Jackson Roberts
- Division of Clinical Pharmacology, Departments of Medicine and Pharmacology, Vanderbilt University School of Medicine, 2222 Pierce Ave., Nashville, Tennessee 37232
| | - Aramandla Ramesh
- Department of Biochemistry and Cancer Biology, Meharry Medical College, 1005 D. B. Todd Blvd., Nashville, TN 37208
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Chakraborty S, Shukla D, Mishra B, Singh S. Lipid – An emerging platform for oral delivery of drugs with poor bioavailability. Eur J Pharm Biopharm 2009; 73:1-15. [DOI: 10.1016/j.ejpb.2009.06.001] [Citation(s) in RCA: 227] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2009] [Revised: 05/30/2009] [Accepted: 06/02/2009] [Indexed: 01/15/2023]
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17
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Walker SA, Ramesh A. RELATIONSHIP BETWEEN DIETARY FAT TYPE AND METABOLIC FATE OF FLUORANTHENE IN F-344 RATS. Polycycl Aromat Compd 2009. [DOI: 10.1080/10406630903127069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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18
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Trevaskis NL, Charman WN, Porter CJ. Lipid-based delivery systems and intestinal lymphatic drug transport: a mechanistic update. Adv Drug Deliv Rev 2008; 60:702-16. [PMID: 18155316 PMCID: PMC7103284 DOI: 10.1016/j.addr.2007.09.007] [Citation(s) in RCA: 277] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2007] [Accepted: 09/30/2007] [Indexed: 12/11/2022]
Abstract
After oral administration, the majority of drug molecules are absorbed across the small intestine and enter the systemic circulation via the portal vein and the liver. For some highly lipophilic drugs (typically log P > 5, lipid solubility > 50 mg/g), however, association with lymph lipoproteins in the enterocyte leads to transport to the systemic circulation via the intestinal lymph. The attendant delivery benefits associated with lymphatic drug transport include a reduction in first-pass metabolism and lymphatic exposure to drug concentrations orders of magnitude higher than that attained in systemic blood. In the current review we briefly describe the mechanisms by which drug molecules access the lymph and the formulation strategies that may be utilised to enhance lymphatic drug transport. Specific focus is directed toward recent advances in understanding regarding the impact of lipid source (both endogenous and exogenous) and intracellular lipid trafficking pathways on lymphatic drug transport and enterocyte-based first-pass metabolism.
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Vasiluk L, Pinto LJ, Tsang WS, Gobas FAPC, Eickhoff C, Moore MM. The uptake and metabolism of benzo[a]pyrene from a sample food substrate in an in vitro model of digestion. Food Chem Toxicol 2007; 46:610-8. [PMID: 17959292 DOI: 10.1016/j.fct.2007.09.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Revised: 08/23/2007] [Accepted: 09/04/2007] [Indexed: 11/28/2022]
Abstract
Food ingestion is the major route of exposure to many hydrophobic organic contaminants (HOCs) such as benzo[a]pyrene (BaP). It has been proposed that food-bound HOCs may become bioavailable after their mobilization by gastrointestinal fluids. The purpose of this research was to measure the uptake efficiency of [(14)C]-BaP bound to skim milk powder using an in vitro model of gastrointestinal digestion followed by sorption to human enterocytes (Caco-2 cells). Neutralization of intestinal fluids released [(14)C]-BaP into the soluble fraction. Ageing of benzo[a]pyrene onto skim milk for 6 months significantly decreased the mobilized fraction but did not affect the amount of benzo[a]pyrene taken up into Caco-2 cells. Hence, significant differences in aqueous phase concentrations may not always be reflected in significant differences in uptake. We obtained evidence that the digestion/uptake of skim milk lipids is accompanied by the diffusive uptake of BaP (the fat flush hypothesis) as trans-cellular transfer of BaP was favoured in the apical to basolateral direction. These data support the theory that non-polar substances including HOCs are preferentially transferred from the lumen into the bloodstream and provide indirect evidence that the uptake is related to the fugacity gradient created by the unidirectional uptake of dietary lipids.
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Affiliation(s)
- Luba Vasiluk
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada V5A 1S6
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20
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Gewurtz SB, Laposa R, Gandhi N, Christensen GN, Evenset A, Gregor D, Diamond ML. A comparison of contaminant dynamics in arctic and temperate fish: A modeling approach. CHEMOSPHERE 2006; 63:1328-41. [PMID: 16293292 DOI: 10.1016/j.chemosphere.2005.09.031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2005] [Revised: 07/26/2005] [Accepted: 09/20/2005] [Indexed: 05/05/2023]
Abstract
In order to compare the abilities of arctic and temperate fish to accumulate PCBs we conduct a metabolic analysis to determine how process rates in a mathematical fish contaminant model change with temperature. We evaluate the model by applying the original and adapted models to estimate PCB concentrations in lake trout (Salvelinus namaycush) in Trout Lake, Ontario, Canada, and in arctic char (Salvelinus alphinus) in Lake Øyangen, in the Norwegian high arctic. Modeled concentrations are, for the most part, within 50% of mean measured values and are comparable to the error associated with the fish data. In order to evaluate differences in fish bioaccumulation processes, the model is applied to hypothetical arctic and temperate systems, assuming the same contaminant input values in water and diet. The model predicts that temperate salmonids are able to biomagnify PCBs 6-60% more than arctic salmonids. For all congeners, the lower BMF(MAX) of arctic fish contribute to their lower concentrations. For congeners with log K(ow) < 6.0, the lower concentrations in arctic fish are also attributed to faster loss due to gill ventilation. Faster growth rates for temperate fish reduce the difference in bioaccumulation for congeners with log K(ow) > 7.0. These processes are controlled by the influence of lipid in the fish and their diet as well as the dependence of growth on temperature. We suggest that fish models originally calibrated for temperate systems may be directly applied to arctic lakes after accounting for the lipid content of the fish and their diet as well as water temperature.
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Affiliation(s)
- Sarah B Gewurtz
- Department of Geography, University of Toronto, 100 St. George Street, Toronto, ON, Canada M5S 3G3
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21
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Marza E, Barthe C, André M, Villeneuve L, Hélou C, Babin PJ. Developmental expression and nutritional regulation of a zebrafish gene homologous to mammalian microsomal triglyceride transfer protein large subunit. Dev Dyn 2005; 232:506-18. [PMID: 15614773 DOI: 10.1002/dvdy.20251] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The microsomal triglyceride transfer protein (MTP) large subunit is required for the assembly and secretion of apolipoprotein B-containing lipoproteins. We have found a zebrafish mtp homologous gene coding a protein with 54% identity with human MTP large subunit with the most conserved regions distributed in the corresponding predicted alpha-helical and C- and A-sheet domains. In situ hybridizations showed that zebrafish mtp transcripts were distributed in the yolk syncytial layer during early embryogenesis and in anterior intestine and liver from 48 hr postfertilization onward. Real-time quantitative RT-PCR confirmed the developmental regulation and tissue-specificity of mtp expression. A significant pretranslational up-regulation of mtp expression was observed in the anterior intestine after feeding. The nutritional regulation of zebrafish mtp expression observed in the anterior intestine supports the notion that this protein, similar to mammalian MTP large subunit, could be a factor implicated directly or indirectly in large lipid droplets accumulation observed in the fish enterocyte after feeding.
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Affiliation(s)
- Esther Marza
- Laboratoire Génomique et Physiologie des Poissons, UMR 1067 NUAGE INRA-IFREMER, Université Bordeaux 1, 33405 Talence Cedex, France
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22
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Cavret S, Feidt C. Intestinal metabolism of PAH: in vitro demonstration and study of its impact on PAH transfer through the intestinal epithelium. ENVIRONMENTAL RESEARCH 2005; 98:22-32. [PMID: 15721880 DOI: 10.1016/j.envres.2004.10.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2003] [Revised: 05/11/2004] [Accepted: 10/29/2004] [Indexed: 05/24/2023]
Abstract
Food would seem to be one of the main ways of animal and human contamination with polycyclic aromatic hydrocarbons (PAHs). In vivo studies suggest a transfer in intestinal epithelium by diffusion, which appears extensively governed by the physicochemical properties of PAHs, particularly lipophilicity. However, other mechanisms, such as metabolism, are considered to intervene. Our work aimed at testing in vitro intestinal metabolism and defining its impact on transepithelial transport of PAHs. Caco-2 cells were cultivated on permeable filters and incubated with 14C-labeled benzo[a]pyrene (BaP), pyrene (Pyr), and phenanthrene (Phe), which differ in their physicochemical properties. The results showed that the cells were able to metabolize the compounds. In basal media, Phe appeared to be the least hydroxylated molecule (45% after a 6-h exposure), followed by Pyr (65%) and finally BaP (96%). Inhibition of PAH metabolism showed a determinant effect on kinetics profiles. Transfer in the basal compartment of BaP, Pyr, and Phe radioactivities was, respectively, 26, 4, and 2 times lower with inhibitors, corroborating that intestinal metabolism of PAHs would have a positive impact on their transfer, an impact that increased with their lipophilicity. Furthermore, after a 6-h incubation, metabolites were also detected in apical medium. These findings suggested that intestinal metabolism might play a key role in intestinal barrier permeability and thus in the bioavailability of tested micropollutants.
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Affiliation(s)
- Séverine Cavret
- ISARAlyon, 31 place Bellecour, F-69288 Lyon Cedex 02, France.
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23
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Cavret S, Feidt C, Laurent F. Differential transfer of organic micropollutants through intestinal barrier using Caco-2 cell line. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2005; 53:2773-2777. [PMID: 15796624 DOI: 10.1021/jf035163w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Food seems to be one of the main ways of animal and human contamination with polycyclic aromatic hydrocarbons (PAHs) and dioxins. In vivo studies showed a blood absorption of these xenobiotics after their ingestion. Our work aimed at studying the in vitro transfer of PAHs and dioxins through intestinal barrier. Caco-2 cells were cultivated on permeable filters to measure transepithelial permeability of (14)C labeled 2,3,7,8-tetrachlorodibenzo-p-dioxin, benzo[a]pyrene, pyrene, and phenanthrene, which differed in their physicochemical properties. The results showed that the molecules were able to cross intestinal cell layers. All the molecules were detected associated with cells, even if the dioxin was the less uptaken compound. Phenanthrene appeared in basal media faster, and its level after a 6-h exposure was respectively 1.1, 2, and 7 times higher than pyrene, benzo[a]pyrene, and 2,3,7,8-tetrachlorodibenzo-p-dioxin levels. These findings suggest that intestinal epithelium plays a key role in selective permeability and then in bioavailibility of micropollutants.
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24
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de Smidt PC, Campanero MA, Trocóniz IF. Intestinal absorption of penclomedine from lipid vehicles in the conscious rat: contribution of emulsification versus digestibility. Int J Pharm 2004; 270:109-18. [PMID: 14726127 DOI: 10.1016/j.ijpharm.2003.10.036] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
While the inclusion of highly lipophilic compounds in self-emulsifying drug delivery systems (SEDDS) is often reported to result in strongly enhanced oral absorption, it is still controversial whether further lipolysis of the dispersed lipidic material is required for final transfer to the enterocyte membranes. In order to assess the relative roles of lipid vehicle dispersion and vehicle digestibility in the oral absorption of penclomedine (Pcm), a series of formulations of Pcm in medium chain triglyceride (MCT)/tocophersolan (TPGS) was developed having three sizes (160 nm, 720 nm, and mm-sized ('crude' oil)); with or without the inclusion of tetrahydrolipstatin (THL), a known lipase-inhibitor. Oral absorption of Pcm was studied after administration of small volumes of these formulations in the conscious rat. Kinetic evaluation was performed using population analysis. Formulations with particle size 160 nm had the highest relative bioavailability (set at F=1), whereas administration in particle size 720 nm had slightly lower bioavailability (F=0.79). Co-inclusion of THL yielded similar bioavailability for these two SEDDS. 'Crude' oil formulations had F=0.62 (without THL) and 0.25 (with THL). The data in the current investigation emphasize the prominent role of increased vehicle dispersion relative to digestibility in the absorption of Pcm from MCT-TPGS in submicron emulsions. Only with Pcm administered as undispersed MCT, absorption was more dependent on the action of lipase as bioavailability was inhibited two-fold by the co-incorporation of THL.
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Affiliation(s)
- P Chris de Smidt
- Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of Navarra, P.O. Box 177, 31080, Pamplona, Spain.
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25
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Cavret S, Rychen G, Feidt C. IN VITRO INTESTINAL TRANSFER AND METABOLISM OF POLYCYCLIC AROMATIC HYDROCARBONS. Polycycl Aromat Compd 2004. [DOI: 10.1080/10406630490471573] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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26
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Voparil IM, Mayer LM, Place AR. Interactions among contaminants and nutritional lipids during mobilization by digestive fluids of marine invertebrates. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2003; 37:3117-3122. [PMID: 12901659 DOI: 10.1021/es026186e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Coastal sediments contain complex mixtures of hydrophobic compounds including organic contaminants such as polycyclic aromatic hydrocarbons and biogenic compounds such as cholesterol and phospholipids. Within the guts of benthic invertebrates, these mixtures are subjected to digestive, chemical conditions that can be rich in surfactants and proteinaceous material. Using in vitro incubations as proxy for digestive exposure, we studied the solubilization of binary mixtures of nutritional and contaminant lipids into artificial seawater and six marine invertebrate gut fluids (Molpadia intermedia, Cucumaria frondosa, Arenicola marina, Arenicola brasiliensis, Parastichopus californicus, and Nereis virens). For animals with surfactant micelles or high protein concentrations, solubilization interactions were frequent. For example, in Arenicola marina gut fluid, benzo(a)pyrene enhanced the solubilization of hexadecane (491% of the compound alone) and palmitic acid (130%) but hindered cholesterol (83%). Benzo(a)pyrene concentrations increased in gut fluids in the presence of cholesterol (137% of BaP alone), phenanthrene (154%), lecithin (140%), and hexadecanol (232%). In A. marina gut fluid, dilution with seawater indicated that these enhancements occur only when micelles are present. Sediment-water partitioning models, used to predict the bioavailability of hydrophobic organic chemicals, do not account for such interactions between solubilizates (compounds solubilized in micelles). However, for animals exposed via a digestive tract containing micelles or high protein concentrations, digestive bioavailability and perhaps bioaccumulation are likely influenced by these interactions.
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Affiliation(s)
- Ian M Voparil
- Darling Marine Center, University of Maine, Walpole, Maine 04573, USA.
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Teles M, Pacheco M, Santos MA. Anguilla anguilla L. liver ethoxyresorufin O-deethylation, glutathione S-transferase, erythrocytic nuclear abnormalities, and endocrine responses to naphthalene and beta-naphthoflavone. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2003; 55:98-107. [PMID: 12706398 DOI: 10.1016/s0147-6513(02)00134-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The effects of naphthalene (NAP) and beta-naphthoflavone (BNF) on phase I biotransformation and genotoxicity in Anguilla anguilla L. were evaluated. Phase II biotransformation and cortisol levels were also assessed in NAP-treated fish. Two groups of eels were exposed to either a NAP or a BNF concentration range (0.1-2.7 microM) for different exposure periods (2-72 h). An early significant ethoxyresorufin O-deethylation (EROD) activity inhibition was observed, especially for the highest NAP concentrations at 2-6 h exposure and for BNF at 2h exposure. However, a significant EROD activity increase was detected from 16 to 72 h exposure for NAP and from 4 to 72 h exposure for BNF. The cytochrome P450 (P450) content was not dose related. However, with regard to BNF exposure, P450 was the first biomarker to respond. Liver alanine transaminase (ALT) activity was measured as an indicator of hepatic health condition. ALT results demonstrated that the EROD activity decrease, previously described for NAP, was not related to tissue damage. Nevertheless, the highest BNF concentrations were demonstrated to induce liver damage and to impair the EROD activity response. An increased genotoxic response, measured as erythrocytic nuclear abnormalities (ENA), was observed during the first 8h NAP exposure. However, for exposures longer than 8 h, ENA frequency returned to the control levels. This response profile may reflect a considerable DNA repair capacity and/or a metabolic adaptation providing an efficient NAP biotransformation and consequent detoxification. BNF revealed no ENA alterations for all concentrations and exposure lengths. In the NAP experiment a causal relationship between immature erythrocytes (IE) and ENA frequency disappearance was not found. BNF results with regard to IE frequency revealed an ability to alter the balance between erythropoiesis and removal of erythrocytes. Liver glutathione S-transferase activity was significantly induced after 2 and 48 h NAP exposure. A cortisol-impaired response seems to occur from 4 to 24 h NAP exposure, demonstrating an endocrine disruption. However, an adaptation process seems to occur after 48 h, since the plasma cortisol had a tendency to increase. The present findings confirm the usefulness of the adopted biomarkers. The ecological risk associated with aquatic contamination by NAP was also confirmed by the present data.
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28
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Page GI, Davies SJ. Astaxanthin and canthaxanthin do not induce liver or kidney xenobiotic-metabolizing enzymes in rainbow trout (Oncorhynchus mykiss Walbaum). Comp Biochem Physiol C Toxicol Pharmacol 2002; 133:443-51. [PMID: 12379428 DOI: 10.1016/s1532-0456(02)00168-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This study was designed to assess the effects of dietary carotenoid supplementation on liver and kidney xenobiotic-metabolizing enzymes in the rainbow trout. Twelve rainbow trout (mean weight 266+/-10 g) were assigned to each of three replicate tanks for each of four dietary treatments; astaxanthin, canthaxanthin, negative control and positive control using beta-naphthoflavone, at a target dietary inclusion of 100 mg kg(-1) for each additive. Fish were fed for 3 weeks at a level of 1.2% body wt. day(-1). Serum carotenoid levels were used as indicators of exposure and were not significantly different (P>0.05) between carotenoid-fed trout. Livers and kidney were frozen separately in liquid N(2) by immersion and microsomal fractions from pooled samples (n=3) assayed for xenobiotic-metabolizing enzyme (cytochrome P450 monoxygenase) activities including ethoxyresorufin O-deethylase; methoxyresorufin O-demethylase; pentoxyresorufin O-dealkylase; benzoxyresorufin O-dearylase; and the conjugating enzymes glucuronosyl transferase; and glutathione-s-transferase. Results revealed that carotenoid treatment did not significantly (P>0.05) induce any enzyme system examined. Results are discussed in the context of metabolism of absorbed carotenoids.
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Affiliation(s)
- G I Page
- Fish Nutrition Unit, Department of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA, UK.
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29
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Moser GA, McLachlan MS. Partitioning of polychlorinated biphenyls and hexachlorobenzene into human faeces. CHEMOSPHERE 2002; 46:449-457. [PMID: 11829401 DOI: 10.1016/s0045-6535(01)00100-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The dietary absorption of persistent lipophilic organic pollutants (PLOPs) in humans is believed to occur via partitioning of the chemical between the lumen and the wall of the digestive tract. As such, the partitioning properties of the lumen contents are a key factor governing absorption. In this study, the partitioning properties of faeces were measured for 11 polychlorinated biphenyls and hexachlorobenzene (HCB). Four volunteers participated in the study, each of them providing faeces from a normal diet and a vegetarian diet. The faeces/gas equilibrium partition coefficient K(FG) varied by over three orders of magnitude between the different compounds. A linear relationship between log K(FG) and log KOA, the octanol/air partition coefficient, was observed. The slope of the relationship was > 1, indicating that the solvent properties of faeces were less polar than those of octanol. For a given compound, KFG varied up to a factor of 2.8 between the individuals on a normal diet. The influence of the vegetarian diet on K(FG) was negligible for the two volunteers who simply deleted fish and animal products from their normal diet, but K(FG) increased on average by a factor of 2 in the two individuals who increased their consumption of less readily digestible whole grains and vegetables in their vegetarian diet. On the basis of K(FG), the fugacities in the faeces were calculated. They were found to be much lower than the fugacities in blood. It is hypothesised that this is due to a temporary decrease in the fugacity in the wall of the jejunum caused by absorption of dietary lipids that results in equilibration between the lumen contents and the wall of the digestive tract at a fugacity below that present in the blood and the rest of the body.
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Affiliation(s)
- G Andreas Moser
- Ecological Chemistry and Geochemistry, University of Bayreuth, Germany
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30
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Sek L, Porter CJH, Kaukonen AM, Charman WN. Evaluation of the in-vitro digestion profiles of long and medium chain glycerides and the phase behaviour of their lipolytic products. J Pharm Pharmacol 2002; 54:29-41. [PMID: 11833493 DOI: 10.1211/0022357021771896] [Citation(s) in RCA: 224] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
An evaluation of the in-vitro digestion profile and phase behaviour of the common formulation lipids Miglyol 812 (medium chain triglyceride, MCT), Capmul MCM (C8/C10 monoglyceride/ diglyceride mixture), soybean oil (long chain triglyceride, LCT) and Maisine 35-1 (C18 monoglyceride/diglyceride mixture), is described. Experiments were conducted using titrimetric, high-performance thin-layer chromatographic (HPTLC) and ultracentrifugational techniques under model fasted and post-prandial intestinal conditions. The rate and extent of digestion of the medium chain lipids was greater than the corresponding long chain lipids, and independent of bile salt concentration, with complete conversion to monoglyceride and fatty acid occurring after 30 min digestion. The long chain lipid digests separated into an oily phase (containing undigested triglyceride and diglyceride), an aqueous phase (containing bile salt, fatty acid and monoglyceride) and a pellet phase (containing approximately 5 mm of fatty acid, presumably as an insoluble soap) after ultracentrifugation. Higher proportions of long chain fatty acid and monoglyceride were dispersed into the aqueous phase with increasing bile salt concentrations. In contrast, medium chain lipolytic products separated only into an aqueous phase and a pellet fraction in a bile-salt-independent manner. The digestion of both the C8/C10 and C18 monoglyceride/diglyceride lipid mixtures was more rapid than the corresponding triglyceride, especially at early time points. This investigation provides insight into the relative digestion kinetics of medium chain and long chain lipids and provides information regarding the phase behaviour of their lipolytic products under conditions modelled on those expected after oral administration. The data also provide a background for improved understanding of the potential utility of long chain and medium chain lipid-based formulations.
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Affiliation(s)
- Leab Sek
- Department of Pharmaceutics, Victorian College of Pharmacy, Monash University, Parkville, Victoria, Australia
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31
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Grova N, Feidt C, Laurent C, Rychen G. Milk, urine and faeces excretion kinetics in lactating goats after an oral administration of aromatic hydrocarbons. Int Dairy J 2002. [DOI: 10.1016/s0958-6946(02)00126-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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32
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Abstract
The term bioaccumulation is defined as uptake, storage, and accumulation of organic and inorganic contaminants by organisms from their environment. Bioaccumulation therefore results from complex interactions between various routes of uptake, excretion, passive release, and metabolization. For fish, the bioaccumulation process includes two routes of uptake: aqueous uptake of water-borne chemicals, and dietary uptake by ingestion of contaminated food particles. The contribution to bioaccumulation that results from aqueous exposure and is taken up by the gills is called bioconcentration. The contribution to bioaccumulation resulting from dietary exposure via uptake by intestinal mucosa is termed biomagnification. In both cases, important co-determinants for bioaccumulation are the various elimination mechanisms. This chapter presents a short historical survey of the problem of bioaccumulation with particular reference to fish and of the various approaches to study bioaccumulation. This is followed by an overview of our present knowledge about basic physico-chemical determinants that either increase or reduce the bioaccumulation potential of various chemicals, and about the physiological basis of gills, blood circulation and intestines, as far as they are crucial for our understanding of uptake and accumulation. Finally, selected quantitative data and modelings of bioaccumulation in fish will be discussed, with regard to such problems as the relative importance of aqueous and dietary uptake.
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Affiliation(s)
- B Streit
- Department of Ecology and Evolution, Biological Sciences, J.W. Goethe-University of Frankfurt, Germany
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33
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Pacheco M, Santos MA. Induction of liver EROD and erythrocytic nuclear abnormalities by cyclophosphamide and PAHs in Anguilla anguilla L. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 1998; 40:71-76. [PMID: 9626538 DOI: 10.1006/eesa.1998.1644] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The induction of liver ethoxyresorufin O-deethylase (EROD) activity and erythrocytic nuclear abnormalities (NA) after treatment with two different polycyclic aromatic hydrocarbons (PAHs) and cyclophosphamide (CP) was investigated in the eel Anguilla anguilla L. EROD activity significantly increases either 3 days after one single i.p. injection or 6 days after two i.p. injections (on days 0 and 3) of 4 mg/kg beta-naphthoflavone (BNF). EROD activity was determined after different lengths of exposure to 4 mg/kg BNF (i.p. injection). The results indicated significant increases from 8-h to 12-day exposure, with a maximum increase at 4 days and a decline between 4 and 12 days. The induction of liver EROD activity and erythrocytic NA was studied, 3 days after one 14.7-mumol/kg treatment (i.p. injection) with BNF, benzo[a]pyrene (BaP), and CP, in three three different groups of eels. The EROD activity significantly increases after BNF and BaP treatment, whereas the erythrocytic NA frequency was kept constant; however, CP induces a significant increase in the erythrocytic NA frequency, but it does not induce a significant increase in liver EROD activity. The sensitivity of A. anguilla liver EROD assay was assessed 3 days after one i.p. injection of BNF (0.0, 0.03, 0.06, 0.125, 0.25, 0.5, 1.0, 2.0, and 4.0 mg/kg). This species exhibits a dose response to BNF at the concentration range 0-4 mg/kg. The NOEL is between 0.125 and 0.25 mg/kg. The eels 3-day exposure to water containing BNF (0.0, 0.1, 0.3, 0.9, and 2.7 microM) induced a significant increase in liver EROD activity, specifically in concentrations of 0.9 and 2.7 microM. The NOEC for the eels external exposure to BNF is between 0.3 and 0.9 microM.
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Affiliation(s)
- M Pacheco
- Department of Biology, University of Aveiro, Portugal
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34
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Sharifi M, Connell WD, Gabric A. Influence of dietary fat on the intestinal absorption of lipophilic compounds in goldfish (Carassius auratus). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 1997; 38:316-321. [PMID: 9469886 DOI: 10.1006/eesa.1997.1548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Dietary uptake of a mixture of pp'DDT and four chlorobenzenes from diets with different lipid contents was measured in goldfish (Carassius auratus) in order to investigate the mechanism of intestinal absorption of organic compounds. The results of the experiments suggest that intestinal absorption is basically controlled by chemical diffusion rather than lipid coassimilation. The extent of dietary uptake as indicated by biomagnification factor was strongly correlated with the chemical log Kow, indicating that uptake of the chemicals from the gastrointestinal fluid is similar to the uptake from other aqueous environments and lipid content of the food in the range used in these experiments (2.9-10.9%) could not influence the uptake of lipophilic chemicals.
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Affiliation(s)
- M Sharifi
- Faculty of Environmental Science, Griffith University, Nathan, Australia
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35
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Dulfer WJ, Groten JP, Govers HA. Effect of fatty acids and the aqueous diffusion barrier on the uptake and transport of polychlorinated biphenyls in Caco-2 cells. J Lipid Res 1996. [DOI: 10.1016/s0022-2275(20)42006-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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36
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Kitts DD, Wijewickreme AN. Effect of dietary caffeic and chlorogenic acids on in vivo xenobiotic enzyme systems. PLANT FOODS FOR HUMAN NUTRITION (DORDRECHT, NETHERLANDS) 1994; 45:287-298. [PMID: 8052584 DOI: 10.1007/bf01094097] [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
The plant phenols chlorogenic and caffeic acids were tested for their affinity to alter hepatic and intestinal xenobiotic Phase I and Phase II enzyme activities in mice. Mice were fed isocaloric and isonitrogenous powdered diets containing 0 and 0.2% caffeic and chlorogenic acids, respectively. Animals pre-treated with benzo(a)pyrene (B(a)P) were sacrificed 18 h after an oral dose (50 mg/kg Bwt). B(a)P induced animals exhibited higher (p < 0.05) microsomal AHH, UDPGT, P-450 and cytosolic GST liver enzyme activities. The presence of these phenolics in the diet was shown to have little effect in modulating hepatic xenobiotic activating-detoxification enzymes. The dietary intake of caffeic and chlorogenic acids was particularly evident with intestinal xenobiotic AHH and GST enzyme activity. These data indicate that the presence of caffeic and chlorogenic acids in the diet may have an integral role in modulating the carcinogenic potential of reactive xenobiotics such as B(a)P.
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Affiliation(s)
- D D Kitts
- Department of Food Science, Faculty of Agricultural Sciences, University of British Columbia, Vancouver, Canada
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37
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Myers RA, Stella VJ. Systemic bioavailability of penclomedine (NSC-338720) from oil-in-water emulsions administered intraduodenally to rats. Int J Pharm 1992. [DOI: 10.1016/0378-5173(92)90374-b] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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38
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James MO, Schell JD, Boyle SM, Altman AH, Cromer EA. Southern flounder hepatic and intestinal metabolism and DNA binding of benzo[a]pyrene (BaP) metabolites following dietary administration of low doses of BaP, BaP-7,8-dihydrodiol or a BaP metabolite mixture. Chem Biol Interact 1991; 79:305-21. [PMID: 1913975 DOI: 10.1016/0009-2797(91)90111-j] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Certain finfish species living in chemically polluted environments exhibit a high incidence of gastrointestinal tract tumors. Carnivorous fish in such environments are likely to consume invertebrates which contain chemical procarcinogens and the invertebrate biotransformation products of these compounds. The retention in tissues, extent of DNA adduct formation in liver and intestine, and metabolite composition of bile was investigated in southern flounder following gavage with pure [3H]- or [14C]benzo[a]pyrene (BaP), pure [14C]benzo[a]pyrene-7,8-dihydrodiol (BaP-7,8D), or hepatopancreas from spiny lobsters previously dosed with [3H]- or [14C]BaP (Metab.HP). Metab.HP contained mainly polar conjugates of BaP diols, triols and tetraols. BaP-7,8D was retained in fish tissues and bile at 24 h to a greater extent (33.6% of the dose), than either BaP (19.00%) or Metab.HP (6.6%). Hepatic and intestinal DNA isolated from all dosed fish contained covalently bound radioactivity, but exposure to BaP-7,8D or BaP resulted in significantly higher binding in both tissues than exposure to Metab.HP. Hepatic DNA from BaP and BaP-7,8D-dosed flounder contained 0.24 +/- 0.07 and 0.33 +/- 0.06 pmol BaP equivalents/mg DNA respectively (mean +/- S.E.), while hepatic DNA isolated from Metab.HP-dosed flounder contained 0.006 +/- 0.002 pmol BaP equivalents/mg DNA. Binding of radioactivity to intestinal DNA was significantly higher than to hepatic DNA for flounder dosed with Metab.HP (0.026 +/- 0.003) or with BaP (0.76 +/- 0.27) but not for flounder dosed with BaP-7,8D (0.44 +/- 0.09). These studies show that dietary BaP, and metabolites likely to be present in invertebrates, can be absorbed by the southern flounder and form DNA adducts in target organs.
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Affiliation(s)
- M O James
- Department of Medicinal Chemistry, JHMHC, University of Florida, Gainesville 32610
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39
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Khan AA, Coppock RW, Schuler MM, Sharma AK, Lillie LE. Induction of hepatic cytochrome P-450 and xenobiotic metabolizing enzymes in rats gavaged with an Alberta crude oil. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH 1989; 28:297-307. [PMID: 2573735 DOI: 10.1080/15287398909531350] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Changes in body weight gain and in biochemical parameters of blood and liver were assessed in Sprague-Dawley rats after multiple oral administration of three test doses of an Alberta crude oil (ACO). Rats treated with ACO (1.25-5 ml/kg) did not show statistically significant (p greater than .05) differences from control, corn-oil treated (5 ml/kg) rats, in body weight gains, liver weight, and blood biochemical indicators of liver (alanine aminotransferase, gamma glutamyltransferase), kidney (blood urea nitrogen, creatinine), and erythrocyte (adenosine 5'-triphosphate, 2,3-diphosphoglyceric acid, reduced glutathione) cytotoxicity. Treatment with ACO, however, caused statistically significant (p less than .05) and dose-related increases from control in (1) microsomal protein and cytochrome P-450 content, and NADPH-cytochrome c reductase, aryl hydrocarbon hydroxylase (AHH), and 7-ethoxycoumarin-O-deethylase (7-ECOD) activities, and (2) cytosolic glutathione transferase activity of liver. The induction of hepatic cytochrome P-450 and xenobiotic-metabolizing enzymes in microsomes of ACO-treated rats was probably associated with dose-related changes in isozymic forms of cytochrome P-450, as evidenced by (1) appearance of a 448-nm spectral peak in microsomes of ACO-treated rats and (2) differences in the inhibition pattern of AHH and 7-ECOD activities in microsomes of control and ACO-treated rats upon treatment with metyrapone and 7,8-benzoflavone.
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Affiliation(s)
- A A Khan
- Animal Sciences Division, Alberta Environmental Centre, Vegreville, Canada
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40
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Schädlich G, Riis V. [Determination of the benzo(a)pyrene content of microbial biomasses and protein feed]. ARCHIV FUR TIERERNAHRUNG 1989; 39:963-70. [PMID: 2619554 DOI: 10.1080/17450398909432977] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A method for the fluorimetric determination of benzo(a)pyrene content is presented consisting of classical clean-up steps. The method was applied to microbial biomasses and different feed stuffs. The investigated yeasts grown on carbohydrates keep the limit of 5 ppb benzo(a)-pyrene recommended by the IUPAC. Yeast samples of the VEB Petrolchemisches Kombinat Schwedt grown on petroleum distillate have a constant quality with benzo(a)pyrene contents at 1 ppb. A selection of bacterial biomasses shows also contents less than 5 ppb. The benzo(a)pyrene contents of biomasses cultivated on liquid manure exceed the given limit.
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41
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42
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Barrowman JA, Rahman A, Lindstrom MB, Borgstrom B. Intestinal absorption and metabolism of hydrocarbons. Prog Lipid Res 1989; 28:189-203. [PMID: 2694176 DOI: 10.1016/0163-7827(89)90012-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- J A Barrowman
- Faculty of Medicine, Memorial University of Newfoundland St. John's, Canada
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43
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Van Veld PA, Patton JS, Lee RF. Effect of preexposure to dietary benzo[a]pyrene (BP) on the first-pass metabolism of BP by the intestine of toadfish (Opsanus tau): in vivo studies using portal vein-catheterized fish. Toxicol Appl Pharmacol 1988; 92:255-65. [PMID: 3341036 DOI: 10.1016/0041-008x(88)90385-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The effect of preexposure of fish to dietary benzo[a]pyrene (BP) on the intestinal metabolism of BP was examined in toadfish (Opsanus tau). The portal veins of toadfish were cannulated following administration of radiolabeled BP to the intestinal lumen. Because these fish lack a lymphatic vessel system, the portal vein is the sole route by which BP and its metabolites enter the circulation. In fish preexposed to dietary BP (10 mg BP/kg food), the radioactivity entering the portal vein was almost entirely (ca. 90%) BP metabolites. In fish fed a laboratory control diet, a smaller percentage (ca. 60%) of the radioactivity entering the portal vein was in the form of BP metabolites. The enhanced efficiency of the intestines of preexposed fish in metabolizing BP appears to be a result of induction of intestinal aryl hydrocarbon hydroxylase (AHH) activity. Intestinal microsomal AHH activities in control and preexposed fish were 0.033 +/- 0.032 and 0.320 +/- 0.060 nmol.min-1.mg-1, respectively. Gel filtration of portal vein plasma indicated differences in the roles of plasma proteins in transporting BP and BP metabolites. Native BP was associated primarily with the high density lipoproteins, whereas organic-soluble BP metabolites were associated primarily with serum albumin fractions. A large percentage of BP metabolites was recovered as water-soluble conjugates. These studies indicate that in fish, the intestine can be an important organ involved in dietary BP metabolism.
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Affiliation(s)
- P A Van Veld
- Skidaway Institute of Oceanography, Savannah, Georgia 31416
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44
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Abstract
The ways in which dietary polyunsaturated fats and antioxidants affect the balance between activation and detoxification of environmental precarcinogens is discussed, with particular reference to the polycyclic aromatic hydrocarbon benzo(a)pyrene. The structure and composition of membranes and their susceptibility to peroxidation is dependent on the polyunsaturated fatty acid (PUFA) content of the cell and its antioxidant status, both of which are determined to a large degree by dietary intake of these compounds. An increase in the PUFA content of membranes stimulates the oxidation of precarcinogens to reactive intermediates by affecting the configuration and induction of membrane-bound enzymes (e.g., the mixed-function oxidase system and epoxide hydratase); providing increased availability of substrates (hydroperoxides) for peroxidases that cooxidise carcinogens (e.g., prostaglandin synthetase and P-450 peroxidase); and increasing the likelihood of direct activation reactions between peroxyl radicals and precarcinogens. Antioxidants, on the other hand, protect against lipid peroxidation, scavenge oxygen-derived free radicals and reactive carcinogenic species. In addition some synthetic antioxidants exert specific effects on enzymes, which results in increased detoxification and reduced rates of activation. The balance between dietary polyunsaturated fats, antioxidants and the initiation of carcinogenesis is discussed in relation to animal models of chemical carcinogenesis and the epidemiology of human cancer.
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Affiliation(s)
- J D Gower
- Division of Comparative Medicine, Clinical Research Centre, Harrow, Middlesex, U.K
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46
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Charman W, Stella V. Estimating the maximal potential for intestinal lymphatic transport of lipophilic drug molecules. Int J Pharm 1986. [DOI: 10.1016/0378-5173(86)90027-x] [Citation(s) in RCA: 113] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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47
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Charman W, Noguchi T, Stella V. An experimental system designed to study the in situ intestinal lymphatic transport of lipophilic drugs in anesthetized rats. Int J Pharm 1986. [DOI: 10.1016/0378-5173(86)90049-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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48
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Charman W, Stella V. Effects of lipid class and lipid vehicle volume on the intestinal lymphatic transport of DDT. Int J Pharm 1986. [DOI: 10.1016/0378-5173(86)90050-5] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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