1
|
Rendic SP, Guengerich FP. Formation of potentially toxic metabolites of drugs in reactions catalyzed by human drug-metabolizing enzymes. Arch Toxicol 2024; 98:1581-1628. [PMID: 38520539 DOI: 10.1007/s00204-024-03710-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 02/20/2024] [Indexed: 03/25/2024]
Abstract
Data are presented on the formation of potentially toxic metabolites of drugs that are substrates of human drug metabolizing enzymes. The tabular data lists the formation of potentially toxic/reactive products. The data were obtained from in vitro experiments and showed that the oxidative reactions predominate (with 96% of the total potential toxication reactions). Reductive reactions (e.g., reduction of nitro to amino group and reductive dehalogenation) participate to the extent of 4%. Of the enzymes, cytochrome P450 (P450, CYP) enzymes catalyzed 72% of the reactions, myeloperoxidase (MPO) 7%, flavin-containing monooxygenase (FMO) 3%, aldehyde oxidase (AOX) 4%, sulfotransferase (SULT) 5%, and a group of minor participating enzymes to the extent of 9%. Within the P450 Superfamily, P450 Subfamily 3A (P450 3A4 and 3A5) participates to the extent of 27% and the Subfamily 2C (P450 2C9 and P450 2C19) to the extent of 16%, together catalyzing 43% of the reactions, followed by P450 Subfamily 1A (P450 1A1 and P450 1A2) with 15%. The P450 2D6 enzyme participated in an extent of 8%, P450 2E1 in 10%, and P450 2B6 in 6% of the reactions. All other enzymes participate to the extent of 14%. The data show that, of the human enzymes analyzed, P450 enzymes were dominant in catalyzing potential toxication reactions of drugs and their metabolites, with the major role assigned to the P450 Subfamily 3A and significant participation of the P450 Subfamilies 2C and 1A, plus the 2D6, 2E1 and 2B6 enzymes contributing. Selected examples of drugs that are activated or proposed to form toxic species are discussed.
Collapse
Affiliation(s)
| | - F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, USA
| |
Collapse
|
2
|
Ip BC, Madnick SJ, Zheng S, van Tongeren TCA, Hall SJ, Li H, Martin S, Spriggs S, Carmichael P, Chen W, Ames D, Breitweiser LA, Pence HE, Bowling AJ, Johnson KJ, Cubberley R, Morgan JR, Boekelheide K. Development of a human liver microphysiological coculture system for higher throughput chemical safety assessment. Toxicol Sci 2024; 199:227-245. [PMID: 38335931 PMCID: PMC11131024 DOI: 10.1093/toxsci/kfae018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2024] Open
Abstract
Chemicals in the systemic circulation can undergo hepatic xenobiotic metabolism, generate metabolites, and exhibit altered toxicity compared with their parent compounds. This article describes a 2-chamber liver-organ coculture model in a higher-throughput 96-well format for the determination of toxicity on target tissues in the presence of physiologically relevant human liver metabolism. This 2-chamber system is a hydrogel formed within each well consisting of a central well (target tissue) and an outer ring-shaped trough (human liver tissue). The target tissue chamber can be configured to accommodate a three-dimensional (3D) spheroid-shaped microtissue, or a 2-dimensional (2D) cell monolayer. Culture medium and compounds freely diffuse between the 2 chambers. Human-differentiated HepaRG liver cells are used to form the 3D human liver microtissues, which displayed robust protein expression of liver biomarkers (albumin, asialoglycoprotein receptor, Phase I cytochrome P450 [CYP3A4] enzyme, multidrug resistance-associated protein 2 transporter, and glycogen), and exhibited Phase I/II enzyme activities over the course of 17 days. Histological and ultrastructural analyses confirmed that the HepaRG microtissues presented a differentiated hepatocyte phenotype, including abundant mitochondria, endoplasmic reticulum, and bile canaliculi. Liver microtissue zonation characteristics could be easily modulated by maturation in different media supplements. Furthermore, our proof-of-concept study demonstrated the efficacy of this coculture model in evaluating testosterone-mediated androgen receptor responses in the presence of human liver metabolism. This liver-organ coculture system provides a practical, higher-throughput testing platform for metabolism-dependent bioactivity assessment of drugs/chemicals to better recapitulate the biological effects and potential toxicity of human exposures.
Collapse
Affiliation(s)
- Blanche C Ip
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02903, USA
- Center for Alternatives to Animals in Testing, Brown University, Providence, Rhode Island 02903, USA
| | - Samantha J Madnick
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02903, USA
- Center for Alternatives to Animals in Testing, Brown University, Providence, Rhode Island 02903, USA
| | - Sophia Zheng
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02903, USA
| | - Tessa C A van Tongeren
- Division of Toxicology, Wageningen University and Research, 6700 EA Wageningen, The Netherlands
| | - Susan J Hall
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02903, USA
| | - Hui Li
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02903, USA
| | - Suzanne Martin
- Unilever, Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, MK44 1LQ Bedfordshire, United Kingdom
| | - Sandrine Spriggs
- Unilever, Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, MK44 1LQ Bedfordshire, United Kingdom
| | - Paul Carmichael
- Unilever, Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, MK44 1LQ Bedfordshire, United Kingdom
| | - Wei Chen
- Corteva, Inc, Indianapolis, Indiana 46268, USA
| | - David Ames
- Corteva, Inc, Indianapolis, Indiana 46268, USA
| | | | | | | | | | - Richard Cubberley
- Unilever, Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, MK44 1LQ Bedfordshire, United Kingdom
| | - Jeffrey R Morgan
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02903, USA
- Center for Alternatives to Animals in Testing, Brown University, Providence, Rhode Island 02903, USA
| | - Kim Boekelheide
- Department of Pathology and Laboratory Medicine, Brown University, Providence, Rhode Island 02903, USA
- Center for Alternatives to Animals in Testing, Brown University, Providence, Rhode Island 02903, USA
| |
Collapse
|
3
|
Chen S, Wu Q, Li X, Li D, Mei N, Ning B, Puig M, Ren Z, Tolleson WH, Guo L. Characterization of cytochrome P450s (CYP)-overexpressing HepG2 cells for assessing drug and chemical-induced liver toxicity. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, TOXICOLOGY AND CARCINOGENESIS 2021; 39:68-86. [PMID: 33576714 PMCID: PMC7931144 DOI: 10.1080/26896583.2021.1880242] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Hepatic metabolism catalyzed by the cytochrome P450 (CYP) superfamily affects liver toxicity associated with exposures to natural compounds and xenobiotic agents. Previously we generated a battery of HepG2-derived stable cell lines that individually express 14 CYPs (1A1, 1A2, 1B1, 2A6, 2B6, 2C8, 2C9, 2C18, 2C19, 2D6, 2E1, 3A4, 3A5, and 3A7). In this study, we comprehensively characterized each cell line for its CYP expression and enzyme activity. Specifically, we measured the mRNA expression, protein expression, and metabolite formation. Using CYP3A4, 2D6, and 2C9-overexpressing cells as representatives, we examined the stability of these cells in long-term cultures for up to 10 passages. The results showed that CYPs can be stably overexpressed for up to 10 cell culture passages without losing their activities. The robustness of responses to stimuli among the cells at different passages was also investigated in CYP3A4-overexpressing cells and the response to amiodarone and dronedarone showed no difference between the cells at the passage 2 and 10. Moreover, the mRNA expression level of most CYPs was higher in CYP-overexpressing HepG2 cells than that in HepaRG cells and primary human hepatocytes. This study confirmed the stability of CYP-overexpressing HepG2 cell lines and provided useful information for a broader use of these cells in pharmacologic and toxicologic research.
Collapse
Affiliation(s)
- Si Chen
- Division of Biochemical Toxicology, National Center for Toxicological Research/U.S. FDA, Jefferson, Arkansas, USA
| | - Qiangen Wu
- Division of Biochemical Toxicology, National Center for Toxicological Research/U.S. FDA, Jefferson, Arkansas, USA
| | - Xilin Li
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research/U.S. FDA, Jefferson, Arkansas, USA
| | - Dongying Li
- Division of Bioinformatics and Biostatistics, National Center for Toxicological Research/U.S. FDA, Jefferson, Arkansas, USA
| | - Nan Mei
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research/U.S. FDA, Jefferson, Arkansas, USA
| | - Baitang Ning
- Division of Bioinformatics and Biostatistics, National Center for Toxicological Research/U.S. FDA, Jefferson, Arkansas, USA
| | - Montserrat Puig
- Division of Biotechnology Review and Research III, Office of Biotechnology Products, Center for Drug Evaluation and Research/U.S. FDA, Silver Spring, Maryland, USA
| | - Zhen Ren
- Division of Biochemical Toxicology, National Center for Toxicological Research/U.S. FDA, Jefferson, Arkansas, USA
| | - William H. Tolleson
- Division of Biochemical Toxicology, National Center for Toxicological Research/U.S. FDA, Jefferson, Arkansas, USA
| | - Lei Guo
- Division of Biochemical Toxicology, National Center for Toxicological Research/U.S. FDA, Jefferson, Arkansas, USA
| |
Collapse
|
4
|
Schütz R, Müller M, Geisslinger F, Vollmar A, Bartel K, Bracher F. Synthesis, biological evaluation and toxicity of novel tetrandrine analogues. Eur J Med Chem 2020; 207:112810. [PMID: 32942071 PMCID: PMC7473156 DOI: 10.1016/j.ejmech.2020.112810] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/22/2020] [Accepted: 08/31/2020] [Indexed: 11/16/2022]
Abstract
In this work, we present the design and synthesis of novel fully synthetic analogues of the bisbenzylisoquinoline tetrandrine, a molecule with numerous pharmacological properties and the potential to treat life-threatening diseases, such as viral infections and cancer. Its toxicity to liver and lungs and the underlying mechanisms, however, are controversially discussed. Along this line, novel tetrandrine analogues were synthesized and biologically evaluated for their hepatotoxicity, as well as their antiproliferative and chemoresistance reversing activity on cancer cells. Previous studies suggesting CYP-mediated toxification of tetrandrine prompted us to amend/replace the suspected metabolically instable 12-methoxy group. Of note, employing several in vitro models showed that the proposed CYP3A4-driven metabolism of tetrandrine and analogues is not the major cause of hepatotoxicity. Biological characterization revealed that some of the novel tetrandrine analogues sensitized drug-resistant leukemia cells by inhibition of the P-glycoprotein. Interestingly, direct anticancer effects improved in comparison to tetrandrine, as several compounds displayed a markedly enhanced ability to reduce proliferation of drug-resistant leukemia cells and to induce cell death of liver cancer cells. Those enhanced anticancer properties were linked to influences on activation of the kinase Akt and mitochondrial events. In sum, our study clarifies the role of CYP3A4-mediated toxicity of the bisbenzylisoquinoline alkaloid tetrandrine and provides the basis for the exploitation of novel synthetic analogues for their antitumoral potential.
Collapse
Affiliation(s)
- Ramona Schütz
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Martin Müller
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Franz Geisslinger
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Angelika Vollmar
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Karin Bartel
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, 81377, Munich, Germany
| | - Franz Bracher
- Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-University of Munich, Butenandtstr. 5-13, 81377, Munich, Germany.
| |
Collapse
|
5
|
Li X, Chen S, Guo X, Wu Q, Seo JE, Guo L, Manjanatha MG, Zhou T, Witt KL, Mei N. Development and Application of TK6-derived Cells Expressing Human Cytochrome P450s for Genotoxicity Testing. Toxicol Sci 2020; 175:251-265. [PMID: 32159784 PMCID: PMC7334878 DOI: 10.1093/toxsci/kfaa035] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Metabolism plays a key role in chemical genotoxicity; however, most mammalian cells used for in vitro genotoxicity testing lack effective metabolizing enzymes. We recently developed a battery of TK6-derived cell lines that individually overexpress 1 of 8 cytochrome P450s (CYP1A1, 1A2, 1B1, 2A6, 2B6, 2C9, 2C19, and 3A4) using a lentiviral expression system. The increased expression and metabolic function of each individual CYP in each established cell line were confirmed using real-time PCR, Western blotting, and mass spectrometry analysis; the parental TK6 cells and empty vector (EV) transduced cells had negligible CYP levels. Subsequently, we evaluated these cell lines using 2 prototypical polyaromatic hydrocarbon mutagens, 7,12-dimethylbenz[a]anthracene (DMBA) and benzo[a]pyrene (B[a]P), that require metabolic activation to exert their genotoxicity. DMBA-induced cytotoxicity, phosphorylation of histone H2A.X, and micronucleus formation were significantly increased in TK6 cells with CYP1A1, 1B1, 2B6, and 2C19 expression as compared with EV controls. B[a]P significantly increased cytotoxicity, DNA damage, and chromosomal damage in TK6 cells overexpressing CYP1A1 and 1B1 when compared with EV controls. B[a]P also induced micronucleus formation in TK6 cells expressing CYP1A2. These results suggest that our CYP-expressing TK6 cell system can be used to detect the genotoxicity of compounds requiring metabolic transformation.
Collapse
Affiliation(s)
- Xilin Li
- Division of Genetic and Molecular Toxicology
| | - Si Chen
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079
| | | | - Qiangen Wu
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079
| | - Ji-Eun Seo
- Division of Genetic and Molecular Toxicology
| | - Lei Guo
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079
| | | | - Tong Zhou
- Center for Veterinary Medicine, U.S. Food and Drug Administration, Rockville, Maryland 20855
| | - Kristine L Witt
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
| | - Nan Mei
- Division of Genetic and Molecular Toxicology
| |
Collapse
|
6
|
Guo X, Seo JE, Li X, Mei N. Genetic toxicity assessment using liver cell models: past, present, and future. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2019; 23:27-50. [PMID: 31746269 DOI: 10.1080/10937404.2019.1692744] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Genotoxic compounds may be detoxified to non-genotoxic metabolites while many pro-carcinogens require metabolic activation to exert their genotoxicity in vivo. Standard genotoxicity assays were developed and utilized for risk assessment for over 40 years. Most of these assays are conducted in metabolically incompetent rodent or human cell lines. Deficient in normal metabolism and relying on exogenous metabolic activation systems, the current in vitro genotoxicity assays often have yielded high false positive rates, which trigger unnecessary and costly in vivo studies. Metabolically active cells such as hepatocytes have been recognized as a promising cell model in predicting genotoxicity of carcinogens in vivo. In recent years, significant advances in tissue culture and biological technologies provided new opportunities for using hepatocytes in genetic toxicology. This review encompasses published studies (both in vitro and in vivo) using hepatocytes for genotoxicity assessment. Findings from both standard and newly developed genotoxicity assays are summarized. Various liver cell models used for genotoxicity assessment are described, including the potential application of advanced liver cell models such as 3D spheroids, organoids, and engineered hepatocytes. An integrated strategy, that includes the use of human-based cells with enhanced biological relevance and throughput, and applying the quantitative analysis of data, may provide an approach for future genotoxicity risk assessment.
Collapse
Affiliation(s)
- Xiaoqing Guo
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, Jefferson, AR, USA
| | - Ji-Eun Seo
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, Jefferson, AR, USA
| | - Xilin Li
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, Jefferson, AR, USA
| | - Nan Mei
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, Jefferson, AR, USA
| |
Collapse
|
7
|
Kishino Y, Hasegawa T, Arakawa S, Shibaya Y, Yamoto T, Mori K. Effect of the metabolic capacity in rat liver S9 on the positive results of in vitro micronucleus tests. J Toxicol Sci 2019; 44:145-153. [PMID: 30842367 DOI: 10.2131/jts.44.145] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A high incidence of positive results is obtained with in vitro genotoxicity tests, which do not correlate with the in vivo negative results in many cases. To address this issue, the metabolic profile of rat liver 9000 × g supernatant fraction (S9) pretreated with phenobarbital (PB) and 5,6-benzoflavone (BNF) was characterized. Furthermore, the in vitro micronucleus tests of 10 compounds were performed with PB-BNF-induced rat S9. PB-BNF increased cytochrome P450 (CYP) activity and CYP1A1, CYP1A2, CYP2B1/2, CYP2C6, CYP3A1, and CYP3A2 expression in rat S9, whereas it decreased CYP2C11 and CYP2E1 expression. PB-BNF-induced S9 enhanced the micronucleus induction (MI) of benzo[a]pyrene (BaP), cyclophosphamide (CPA), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine hydrochloride (PhIP), which are metabolized by CYP1A1, CYP2C6, and CYP1A2, respectively. In contrast, coumarin and chlorpheniramine showed MI with PB-BNF-induced S9 despite the fact that they show negative results in the in vivo studies. Furthermore, diclofenac, piroxicam, lansoprazole, and caffeine showed MI regardless of the enzyme induction by PB-BNF, whereas phenacetin did not show MI. These results indicate that PB-BNF-induced rat S9 is effective in detecting the genotoxic potential of promutagens, such as BaP, CPA, and PhIP, but not of coumarin and chlorpheniramine, probably due to the differences in the in vitro and in vivo metabolic profile and its exposure levels of the drugs.
Collapse
Affiliation(s)
- Yuki Kishino
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd
| | - Tomoko Hasegawa
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd
| | - Shingo Arakawa
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd
| | - Yukari Shibaya
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd
| | - Takashi Yamoto
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd
| | - Kazuhiko Mori
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd
| |
Collapse
|
8
|
Metabolism of the Marine Phycotoxin PTX-2 and Its Effects on Hepatic Xenobiotic Metabolism: Activation of Nuclear Receptors and Modulation of the Phase I Cytochrome P450. Toxins (Basel) 2017; 9:toxins9070212. [PMID: 28678150 PMCID: PMC5535159 DOI: 10.3390/toxins9070212] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 06/30/2017] [Accepted: 07/01/2017] [Indexed: 11/29/2022] Open
Abstract
PTX-2 is a marine biotoxin frequently found in shellfish that can lead to food intoxication in humans. Information regarding PTX-2 metabolism is scarce, and little is known of its effect on xenobiotic-metabolizing enzymes (XME) or its molecular pathways. The aim of this study was consequently to examine PTX-2 Phase I metabolism using rat and human liver S9 fractions, and also to assess the capability of PTX-2: (i) to modulate the gene expression of a panel of Phase I (CYP450) and II (UGT, SULT, NAT, and GST) enzymes, as well as the Phase III or 0 (ABC and SLCO) transporters in the human hepatic HepaRG cell line using qPCR; (ii) to induce specific CYP450 in HepaRG cells measured by immunolabeling detection and the measurement of the cells’ activities; and (iii) to activate nuclear receptors and induce CYP promoter activities in HEK-T and HepG2 transfected cell lines using transactivation and reporter gene assay, respectively. Our results indicate that PTX-2 hydroxylation occurred with both rat and human S9 fractions. Whereas PTX-2 mostly upregulated the gene expression of CYP1A1 and 1A2, no induction of these two CYP activities was observed. Lastly, PTX-2 did not act as an agonist of CAR or PXR. Due to its effects on some key XME, more attention should be paid to possible drug–drug interactions with phycotoxins, especially as shellfish can accumulate several phycotoxins as well as other kinds of contaminants.
Collapse
|
9
|
Kolrep F, Rein K, Lampen A, Hessel-Pras S. Metabolism of okadaic acid by NADPH-dependent enzymes present in human or rat liver S9 fractions results in different toxic effects. Toxicol In Vitro 2017; 42:161-170. [PMID: 28414161 DOI: 10.1016/j.tiv.2017.04.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 03/24/2017] [Accepted: 04/11/2017] [Indexed: 12/16/2022]
Abstract
The lipophilic marine biotoxin okadaic acid (OA) represents a natural contaminant produced by algae accumulating in seafood. Acute intoxications result in diarrhetic shellfish poisoning causing symptoms like nausea, vomiting and abdominal cramps. OA was preincubated with liver enzymes present in S9 fractions from humans, rats and rats pretreated with enzyme inducers in the presence or absence of the cofactor NADPH to investigate hepatic metabolism. Cytotoxicity was examined in HepG2 cells and metabolites of OA were determined by LC-MS/MS. Strong cytotoxicity was observed in HepG2 cells treated with OA that was preincubated in S9 fractions without NADPH. However, neither metabolites nor a decrease of OA itself were found. The addition of NADPH to the S9 fractions of rats resulted in a decreased cytotoxicity of OA, but a stronger toxicity in HepG2 cells was observed from OA preincubated in human S9 fractions with NADPH. Metabolite profiles of each S9 mix revealed that higher amounts of detoxified metabolites were formed by NADPH-dependent enzymes of rats compared to the same enzymes of humans. These differences in OA detoxification by NADPH-dependent liver enzymes of rats and humans may be of significance in the extrapolation of toxicological data from animal models (rats to humans, for example).
Collapse
Affiliation(s)
- Franziska Kolrep
- Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany.
| | - Kathleen Rein
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th St., Miami, FL 33199, USA.
| | - Alfonso Lampen
- Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany.
| | - Stefanie Hessel-Pras
- Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany.
| |
Collapse
|
10
|
Le Bihanic F, Di Bucchianico S, Karlsson HL, Dreij K. In vivo
micronucleus screening in zebrafish by flow cytometry. Mutagenesis 2016; 31:643-653. [DOI: 10.1093/mutage/gew032] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
11
|
Kolrep F, Hessel S, These A, Ehlers A, Rein K, Lampen A. Differences in metabolism of the marine biotoxin okadaic acid by human and rat cytochrome P450 monooxygenases. Arch Toxicol 2015; 90:2025-36. [DOI: 10.1007/s00204-015-1591-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/31/2015] [Indexed: 02/07/2023]
|
12
|
Abstract
The ageing process is influenced by many internal and external factors. The toxic substances in the environment can cause genomic damages to cells, which increase the risk of early ageing. Furthermore, the cytochrome P450 1A2 (CYP1A2) gene polymorphism is a susceptibility factor and may enhance the risk of DNA damage in cells. The current study was carried out to show whether occupational exposure could cause genotoxicity in cells carrying the CYP1A2 gene polymorphism, thus enhancing the likelihood of early ageing. This study was conducted on mechanical workshop workers and a control group by collecting buccal cells from their mouths. Restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) was used to identify the CYP1A2 gene polymorphism in the cells. In addition, three extra methods including micronuclei (MN) test, comet assay and real-time PCR (RT-PCR) were applied to determine the effects of gene polymorphisms on DNA damage and ageing from occupational exposure. The results showed that DNA damage in the cells carrying the mutated genotype was higher than the wild genotype. In addition, the difference in MN frequency (p = 0.001) and relative telomere length (p = 0.002) between workers and controls was significant (p <0.05) in the mutated genotype. The findings indicated a possible protective effect of gene polymorphism against early ageing, which was characterized by lack of a significant influence of CYP1A2 gene polymorphism on genetic material in the subjects (p >0.05). It was concluded that the CYP1A2 gene could be a contributing factor to prevent early ageing from occupational exposure.
Collapse
|
13
|
Development of a novel, physiologically relevant cytotoxicity model: Application to the study of chemotherapeutic damage to mesenchymal stromal cells. Toxicol Appl Pharmacol 2012; 263:374-89. [DOI: 10.1016/j.taap.2012.07.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 06/25/2012] [Accepted: 07/16/2012] [Indexed: 11/17/2022]
|
14
|
Abstract
Considerable support exists for the roles of metabolism in modulating the carcinogenic properties of chemicals. In particular, many of these compounds are pro-carcinogens that require activation to electrophilic forms to exert genotoxic effects. We systematically analyzed the existing literature on the metabolism of carcinogens by human enzymes, which has been developed largely in the past 25 years. The metabolism and especially bioactivation of carcinogens are dominated by cytochrome P450 enzymes (66% of bioactivations). Within this group, six P450s--1A1, 1A2, 1B1, 2A6, 2E1, and 3A4--accounted for 77% of the P450 activation reactions. The roles of these P450s can be compared with those estimated for drug metabolism and should be considered in issues involving enzyme induction, chemoprevention, molecular epidemiology, interindividual variations, and risk assessment.
Collapse
|
15
|
Fieber LA, Greer JB, Guo F, Crawford DC, Rein KS. GENE EXPRESSION PROFILING OF HUMAN LIVER CARCINOMA (HepG2) CELLS EXPOSED TO THE MARINE TOXIN OKADAIC ACID. TOXICOLOGICAL AND ENVIRONMENTAL CHEMISTRY 2012; 24:1805-1821. [PMID: 23172983 PMCID: PMC3500632 DOI: 10.1080/02772248.2012.730199] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The marine toxin, okadaic acid (OA) is produced by dinoflagellates of the genera Prorocentrum and Dinophysis and is the causative agent of the syndrome known as diarrheic shellfish poisoning (DSP). In addition, OA acts as both a tumor promoter, attributed to OA-induced inhibition of protein phosphatases as well as an inducer of apoptosis. To better understand the potentially divergent toxicological profile of OA, the concentration dependent cytotoxicity and alterations in gene expression on the human liver tumor cell line HepG2 upon OA exposure were determined using RNA microarrays, DNA fragmentation, and cell proliferation assays as well as determinations of cell detachment and cell death in different concentrations of OA. mRNA expression was quantified for approximately 15,000 genes. Cell attachment and proliferation were both negatively correlated with OA concentration. Detached cells displayed necrotic DNA signatures but apoptosis also was broadly observed. Data suggest that OA has a concentration dependent effect on cell cycle, which might explain the divergent effects that at low concentration OA stimulates genes involved in the cell cycle and at high concentrations it stimulates apoptosis.
Collapse
Affiliation(s)
- Lynne A. Fieber
- Division of Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, 4600 Rickenbacker Cswy, Miami, FL, USA 33149
| | - Justin B. Greer
- Division of Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, 4600 Rickenbacker Cswy, Miami, FL, USA 33149
| | - Fujiang Guo
- Department of Chemistry and Biochemistry, 11200 SW 8 St, Florida International University, Miami, FL, USA33199
| | - Douglas C. Crawford
- Division of Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, 4600 Rickenbacker Cswy, Miami, FL, USA 33149
| | - Kathleen S. Rein
- Department of Chemistry and Biochemistry, 11200 SW 8 St, Florida International University, Miami, FL, USA33199
| |
Collapse
|
16
|
Kashyap MP, Singh AK, Kumar V, Tripathi VK, Srivastava RK, Agrawal M, Khanna VK, Yadav S, Jain SK, Pant AB. Monocrotophos induced apoptosis in PC12 cells: role of xenobiotic metabolizing cytochrome P450s. PLoS One 2011; 6:e17757. [PMID: 21445290 PMCID: PMC3061860 DOI: 10.1371/journal.pone.0017757] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Accepted: 02/09/2011] [Indexed: 12/30/2022] Open
Abstract
Monocrotophos (MCP) is a widely used organophosphate (OP) pesticide. We studied apoptotic changes and their correlation with expression of selected cytochrome P450s (CYPs) in PC12 cells exposed to MCP. A significant induction in reactive oxygen species (ROS) and decrease in glutathione (GSH) levels were observed in cells exposed to MCP. Following the exposure of PC12 cells to MCP (10−5 M), the levels of protein and mRNA expressions of caspase-3/9, Bax, Bcl2, P53, P21, GSTP1-1 were significantly upregulated, whereas the levels of Bclw, Mcl1 were downregulated. A significant induction in the expression of CYP1A1/1A2, 2B1/2B2, 2E1 was also observed in PC12 cells exposed to MCP (10−5 M), whereas induction of CYPs was insignificant in cells exposed to 10−6 M concentration of MCP. We believe that this is the first report showing altered expressions of selected CYPs in MCP-induced apoptosis in PC12 cells. These apoptotic changes were mitochondria mediated and regulated by caspase cascade. Our data confirm the involvement of specific CYPs in MCP-induced apoptosis in PC12 cells and also identifies possible cellular and molecular mechanisms of organophosphate pesticide-induced apoptosis in neuronal cells.
Collapse
Affiliation(s)
- Mahendra Pratap Kashyap
- Indian Institute of Toxicology Research, Lucknow, India
- Council of Scientific and Industrial Research, New Delhi, India
| | - Abhishek Kumar Singh
- Indian Institute of Toxicology Research, Lucknow, India
- Council of Scientific and Industrial Research, New Delhi, India
| | - Vivek Kumar
- Indian Institute of Toxicology Research, Lucknow, India
- Council of Scientific and Industrial Research, New Delhi, India
| | - Vinay Kumar Tripathi
- Indian Institute of Toxicology Research, Lucknow, India
- Council of Scientific and Industrial Research, New Delhi, India
| | - Ritesh Kumar Srivastava
- Indian Institute of Toxicology Research, Lucknow, India
- Council of Scientific and Industrial Research, New Delhi, India
| | - Megha Agrawal
- Indian Institute of Toxicology Research, Lucknow, India
- Council of Scientific and Industrial Research, New Delhi, India
| | - Vinay Kumar Khanna
- Indian Institute of Toxicology Research, Lucknow, India
- Council of Scientific and Industrial Research, New Delhi, India
| | - Sanjay Yadav
- Indian Institute of Toxicology Research, Lucknow, India
- Council of Scientific and Industrial Research, New Delhi, India
| | | | - Aditya Bhushan Pant
- Indian Institute of Toxicology Research, Lucknow, India
- Council of Scientific and Industrial Research, New Delhi, India
- * E-mail:
| |
Collapse
|
17
|
Fagundes Soares Garcia AC, Marcon AE, Ferreira DDM, Barbosa dos Santos EA, do Amaral VS, Medeiros SRBD. Micronucleus study of the quality and mutagenicity of surface water from a semi-arid region. ACTA ACUST UNITED AC 2011; 13:3329-35. [DOI: 10.1039/c1em10582e] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
18
|
Hashizume T, Yoshitomi S, Asahi S, Uematsu R, Matsumura S, Chatani F, Oda H. Advantages of Human Hepatocyte-Derived Transformants Expressing a Series of Human Cytochrome P450 Isoforms for Genotoxicity Examination. Toxicol Sci 2010; 116:488-97. [DOI: 10.1093/toxsci/kfq154] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
19
|
Miyamoto S, Matsumoto A, Mori I, Horinouchi A. Relationship between in vitro phospholipidosis assay using HepG2 cells and 2-week toxicity studies in rats. Toxicol Mech Methods 2010; 19:477-85. [PMID: 19793005 DOI: 10.1080/15376510903322834] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Drug candidates under development by industry frequently show phospholipidosis as a side-effect in pre-clinical toxicity studies. This study sets up a cell-based assay for drug-induced phospholipidosis (PLD) and its performance was evaluated based on the in vivo PLD potential of compounds in 2-week toxicity studies in rats. When HepG2 cells were exposed simultaneously to PLD-inducing chemicals and a phospholipid having a fluorophore, an accumulation of phospholipids was detected as an increasing fluorescent intensity. Amiodarone, amitriptyline, fluoxetine, AY-9944, and perhexiline, which are common PLD-inducing chemicals, increased the fluorescent intensity, but acetaminophen, ampicillin, cimetidine, famotidine, or valproic acid, which are non-PLD-inducing chemicals, did not. The fluorescent intensity showed concordance with the pathological observations of phospholipid lamellar bodies in the cells. Then to confirm the predictive performance of the in vitro PLD assay, the 32 proprietary compounds characterized in 2-week toxicity studies in rats were evaluated with this in vitro assay. Because this in vitro assay was vulnerable to cytotoxicity, the innate PLD potential was calculated for each compound. A statistically significant increase in the in vitro PLD potential was seen for the compounds having in vivo PLD-inducing potential in the rat toxicity studies. The results suggest that the in vitro PLD potential could be appropriate to detect the appearance of PLD as a side effect in pre-clinical toxicity studies in rats.
Collapse
Affiliation(s)
- Saku Miyamoto
- Development Research Center, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Osaka, Japan.
| | | | | | | |
Collapse
|