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Hernandez‐Jerez AF, Adriaanse P, Aldrich A, Berny P, Coja T, Duquesne S, Focks A, Marinovich M, Millet M, Pelkonen O, Pieper S, Tiktak A, Topping CJ, Widenfalk A, Wilks M, Wolterink G, Gundert‐Remy U, Louisse J, Rudaz S, Testai E, Lostia A, Dorne J, Parra Morte JM. Scientific Opinion of the Scientific Panel on Plant Protection Products and their Residues (PPR Panel) on testing and interpretation of comparative in vitro metabolism studies. EFSA J 2021; 19:e06970. [PMID: 34987623 PMCID: PMC8696562 DOI: 10.2903/j.efsa.2021.6970] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
EFSA asked the Panel on Plant Protection Products and their residues to deliver a Scientific Opinion on testing and interpretation of comparative in vitro metabolism studies for both new active substances and existing ones. The main aim of comparative in vitro metabolism studies of pesticide active substances is to evaluate whether all significant metabolites formed in the human in vitro test system, as a surrogate of the in vivo situation, are also present at comparable level in animal species tested in toxicological studies and, therefore, if their potential toxicity has been appropriately covered by animal studies. The studies may also help to decide which animal model, with regard to a particular compound, is the most relevant for humans. In the experimental strategy, primary hepatocytes in suspension or culture are recommended since hepatocytes are considered the most representative in vitro system for prediction of in vivo metabolites. The experimental design of 3 × 3 × 3 (concentrations, time points, technical replicates, on pooled hepatocytes) will maximise the chance to identify unique (UHM) and disproportionate (DHM) human metabolites. When DHM and UHM are being assessed, test item-related radioactivity recovery and metabolite profile are the most important parameters. Subsequently, structural characterisation of the assigned metabolites is performed with appropriate analytical techniques. In toxicological assessment of metabolites, the uncertainty factor approach is the first alternative to testing option, followed by new approach methodologies (QSAR, read-across, in vitro methods), and only if these fail, in vivo animal toxicity studies may be performed. Knowledge of in vitro metabolites in human and animal hepatocytes would enable toxicological evaluation of all metabolites of concern, and, furthermore, add useful pieces of information for detection and evaluation of metabolites in different matrices (crops, livestock, environment), improve biomonitoring efforts via better toxicokinetic understanding, and ultimately, develop regulatory schemes employing physiologically based or physiology-mimicking in silico and/or in vitro test systems to anticipate the exposure of humans to potentially hazardous substances in plant protection products.
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Chanteux H, Rosa M, Delatour C, Nicolaï J, Gillent E, Dell'Aiera S, Ungell AL. Application of Azamulin to Determine the Contribution of CYP3A4/5 to Drug Metabolic Clearance Using Human Hepatocytes. Drug Metab Dispos 2020; 48:778-787. [PMID: 32532738 DOI: 10.1124/dmd.120.000017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 06/01/2020] [Indexed: 11/22/2022] Open
Abstract
Early determination of CYP3A4/5 contribution to the clearance of new chemical entities is critical to inform on the risk of drug-drug interactions with CYP3A inhibitors and inducers. Several in vitro approaches (recombinant P450 enzymes, correlation analysis, chemical and antibody inhibition in human liver microsomes) are available, but they are usually labor-intensive and/or suffer from specific limitations. In the present study, we have validated the use of azamulin as a specific CYP3A inhibitor in human hepatocytes. Azamulin (3 µM) was found to significantly inhibit CYP3A4/5 (>90%), whereas other P450 enzymes were not affected (less than 20% inhibition). Because human hepatocytes were used as a test system, the effect of azamulin on other key drug-metabolizing enzymes (aldehyde oxidase, carboxylesterase, UGT, flavin monooxygenase, and sulfotransferase) was also investigated. Apart from some UGTs showing minor inhibition (∼20%-30%), none of these non-P450 enzymes were inhibited by azamulin. Use of CYP3A5-genotyped human hepatocyte batches in combination with CYP3cide demonstrated that azamulin (at 3 µM) inhibits both CYP3A4 and CYP3A5 enzymes. Finally, 11 compounds with known in vivo CYP3A4/5 contribution have been evaluated in this human hepatocyte assay. Results showed that the effect of azamulin on the in vitro intrinsic clearance of these known CYP3A4/5 substrates was predictive of the in vivo CYP3A4/5 contribution. Overall, the study showed that human hepatocytes treated with azamulin provide a fast and accurate estimation of CYP3A4/5 contribution in metabolic clearance of new chemical entities. SIGNIFICANCE STATEMENT: Accurate estimation of CYP3A4/5 contribution in drug clearance is essential to anticipate risk of drug-drug interactions and select the appropriate candidate for clinical development. The present study validated the use of azamulin as selective CYP3A4/5 inhibitor in suspended human hepatocytes and demonstrated that this novel approach provides a direct and accurate determination of the contribution of CYP3A4/5 (fraction metabolized by CYP3A4/5) in the metabolic clearance of new chemical entities.
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Affiliation(s)
| | - Maria Rosa
- UCB Biopharma SRL, Braine-l'Alleud, Belgium
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Ancuceanu R, Dinu M, Dinu-Pirvu C, Anuţa V, Negulescu V. Pharmacokinetics of B-Ring Unsubstituted Flavones. Pharmaceutics 2019; 11:E370. [PMID: 31374885 PMCID: PMC6723510 DOI: 10.3390/pharmaceutics11080370] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 07/23/2019] [Accepted: 07/23/2019] [Indexed: 02/07/2023] Open
Abstract
B-ring unsubstituted flavones (of which the most widely known are chrysin, baicalein, wogonin, and oroxylin A) are 2-phenylchromen-4-one molecules of which the B-ring is devoid of any hydroxy, methoxy, or other substituent. They may be found naturally in a number of herbal products used for therapeutic purposes, and several have been designed by researchers and obtained in the laboratory. They have generated interest in the scientific community for their potential use in a variety of pathologies, and understanding their pharmacokinetics is important for a grasp of their optimal use. Based on a comprehensive survey of the relevant literature, this paper examines their absorption (with deglycosylation as a preliminary step) and their fate in the body, from metabolism to excretion. Differences among species (inter-individual) and within the same species (intra-individual) variability have been examined based on the available data, and finally, knowledge gaps and directions of future research are discussed.
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Affiliation(s)
- Robert Ancuceanu
- Department of Pharmaceutical Botany and Cell Biology, Faculty of Pharmacy, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Mihaela Dinu
- Department of Pharmaceutical Botany and Cell Biology, Faculty of Pharmacy, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
| | - Cristina Dinu-Pirvu
- Department of Physical Chemistry and Colloidal Chemistry, Faculty of Pharmacy, Carol Davila University of Medicine and Pharmacy, 020956 Bucharest 020956, Romania
| | - Valentina Anuţa
- Department of Physical Chemistry and Colloidal Chemistry, Faculty of Pharmacy, Carol Davila University of Medicine and Pharmacy, 020956 Bucharest 020956, Romania
| | - Vlad Negulescu
- Department of Toxicology, Clinical Pharmacology and Psychopharmacology, Faculty of Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania
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Zhang Z, Liu D, Jiang J, Song X, Zou X, Chu S, Xie K, Dai J, Chen N, Sheng L, Li Y. Metabolism of IMM-H004 and Its Pharmacokinetic-Pharmacodynamic Analysis in Cerebral Ischemia/Reperfusion Injured Rats. Front Pharmacol 2019; 10:631. [PMID: 31249524 PMCID: PMC6584114 DOI: 10.3389/fphar.2019.00631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Accepted: 05/17/2019] [Indexed: 12/23/2022] Open
Abstract
IMM-H004, a derivative of coumarin, is a promising candidate for the treatment of cerebral ischemia. The pharmacodynamic mechanisms of IMM-H004 are still under exploration. The present study was conducted to explore the pharmacoactive substances of IMM-H004 from the perspective of drug metabolism. Four metabolites of IMM-H004 including demethylated metabolites M1 and M2, glucuronide conjugate IMM-H004G (M3), and sulfated conjugate M4 were found in rats in vivo. IMM-H004G was the major metabolite in rats and cultured human hepatocytes, and uridine diphosphate-glucuronosyltransferase (UGT) was found to catalyze the metabolism of IMM-H004 in human liver microsomes (HLMs) and rat liver microsomes (RLMs) with high capacity (V max at 3.25 and 5.04 nmol/min/mg protein). Among 13 recombinant human UGT isoforms, UGT1A7, 1A9, 1A8, and 1A1 appeared to be primarily responsible for IMM-H004G formation. The exposure and duration of IMM-H004G (28,948 h × ng/ml of area under the plasma concentration-time curve (AUC), 6.61 h of t 1/2β) was much higher than that of the parent drug (1,638 h × ng/ml of AUC, 0.42 h of t 1/2β) in transient middle cerebral artery occlusion/reperfusion (MCAO/R) rats, consistent with the malondialdehyde (MDA) inhibition effect for at least 10 h. Further pharmacological study revealed that IMM-H004G exhibited a similar neuroprotective activity to that of the parent drug on both oxygen-glucose deprivation injured PC12 cells and transient MCAO/R injured rats. These results demonstrate that both prototype and IMM-H004G are the active pharmaceutical substances, and IMM-H004G, at least in part, contributes to the maintenance of anti-cerebral ischemia efficacy of IMM-H004.
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Affiliation(s)
- Ziqian Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Laboratory of Non-Clinical Drug Metabolism and PK/PD Study, Key Laboratory of Active Substances Discovery and Drug Ability Evaluation, State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Dandan Liu
- State Key Laboratory of Bioactive Substances and Function Natural Medicines, Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Jianwei Jiang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Laboratory of Non-Clinical Drug Metabolism and PK/PD Study, Key Laboratory of Active Substances Discovery and Drug Ability Evaluation, State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,State Key Laboratory of Bioactive Substances and Function Natural Medicines, Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xiuyun Song
- State Key Laboratory of Bioactive Substances and Function Natural Medicines, Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xiaowen Zou
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Laboratory of Non-Clinical Drug Metabolism and PK/PD Study, Key Laboratory of Active Substances Discovery and Drug Ability Evaluation, State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Shifeng Chu
- State Key Laboratory of Bioactive Substances and Function Natural Medicines, Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Kebo Xie
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jungui Dai
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Naihong Chen
- State Key Laboratory of Bioactive Substances and Function Natural Medicines, Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Li Sheng
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Laboratory of Non-Clinical Drug Metabolism and PK/PD Study, Key Laboratory of Active Substances Discovery and Drug Ability Evaluation, State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yan Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Beijing Laboratory of Non-Clinical Drug Metabolism and PK/PD Study, Key Laboratory of Active Substances Discovery and Drug Ability Evaluation, State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Department of Drug Metabolism, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Li Y, Song W, Ou X, Luo G, Xie Y, Sun R, Wang Y, Qi X, Hu M, Liu Z, Zhu L. Breast Cancer Resistance Protein and Multidrug Resistance Protein 2 Determine the Disposition of Esculetin-7-O-Glucuronide and 4-Methylesculetin-7-O-Glucuronide. Drug Metab Dispos 2019; 47:203-214. [PMID: 30602435 DOI: 10.1124/dmd.118.083493] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 12/27/2018] [Indexed: 01/02/2023] Open
Abstract
Esculetin (ET)-7-O-glucuronide (ET-G) and 4-methylesculetin (4-ME)-7-O-glucuronide (4-ME-G) are the main glucuronide of ET and 4-ME, respectively. The disposition mediated by efflux transporters for glucuronide has significant influence on the pharmacokinetic profile and efficacy of bioactive compounds. In the current study, transporter gene knockout mice and Caco-2 cells were used to explore the effects of breast cancer resistance protein (BCRP) and multidrug resistance-associated protein 2 (MRP2) on the disposition of ET-G and 4-ME-G. After oral or i.v. administration of ET and 4-ME, the area under the plasma concentration-time curve from time 0 to the last data point or infinity values of ET, 4-ME, and their glucuronides (ET-G and 4-ME-G) were remarkably and significantly increased in most Bcrp1-/- and Mrp2-/- mice compared with those in wild-type FVB mice (P < 0.05). These results were accompanied with a significant increase of maximum plasma concentration values (P < 0.05). In Caco-2 monolayers, the efflux and clearance rates of ET-G and 4-ME-G were markedly reduced by the BCRP inhibitor Ko143 and MRP2 inhibitor MK571 on the apical side (P < 0.05). In an intestinal perfusion study, the excretion of ET-G was significantly decreased in perfusate and increased in plasma in Bcrp1-/- mice compared with those in wild-type FVB mice (P < 0.05). The 4-ME-G concentration was also decreased in the bile in transporter gene knockout mice. ET and 4-ME showed good permeability in both Caco-2 monolayers [apparent permeability (Papp ) ≥ 0.59 × 10-5 cm/s] and duodenum (Papp ≥ 1.81). In conclusion, BCRP and MRP2 are involved in excreting ET-G and 4-ME-G. ET and 4-ME are most likely absorbed via passive diffusion in the intestines.
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Affiliation(s)
- Yuhuan Li
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
| | - Wenjie Song
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
| | - Xiaojun Ou
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
| | - Guangkuo Luo
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
| | - Yushan Xie
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
| | - Rongjin Sun
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
| | - Ying Wang
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
| | - Xiaoxiao Qi
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
| | - Ming Hu
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
| | - Zhongqiu Liu
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
| | - Lijun Zhu
- Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People's Republic of China (Y.L., W.S., X.O., G.L., Y.X., R.S., Y.W., X.Q., M.H., Z.L., L.Z.); State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (Special Administration Region), People's Republic of China (Z.L.); and Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas (M.H.)
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6
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Iswandana R, Irianti MI, Oosterhuis D, Hofker HS, Merema MT, de Jager MH, Mutsaers HAM, Olinga P. Regional Differences in Human Intestinal Drug Metabolism. Drug Metab Dispos 2018; 46:1879-1885. [DOI: 10.1124/dmd.118.083428] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 09/27/2018] [Indexed: 01/05/2023] Open
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Xia YL, Dou TY, Liu Y, Wang P, Ge GB, Yang L. In vitro evaluation of the effect of C-4 substitution on methylation of 7,8-dihydroxycoumarin: metabolic profile and catalytic kinetics. ROYAL SOCIETY OPEN SCIENCE 2018; 5:171271. [PMID: 29410835 PMCID: PMC5792912 DOI: 10.1098/rsos.171271] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 11/24/2017] [Indexed: 06/08/2023]
Abstract
Daphnetin (7,8-dihydroxycoumarin (7,8-DHC)) and its C-4 derivatives have multiple pharmacological activities, but the poor metabolic stability of these catechols has severely restricted their application in the clinic. Methylation plays important roles in catechol elimination, although thus far the effects of structural modifications on the metabolic selectivity and the catalytic efficacy of human catechol-O-methyltransferase (COMT) remain unclear. This study was aimed at exploring the structure-methylation relationship of daphnetin and its C-4 derivatives, including 4-methyl, 4-phenyl and 4-acetic acid daphnetin. It was achieved by identifying the methylated products generated and by careful characterization of the reaction kinetics. These catechols are selectively metabolized to the corresponding 8-O-methyl conjugates, and this regioselective methylation could be elucidated by flexible docking, in which all the 8-OH groups of these catechols are much closer than the 7-OH groups to catalytic residue LYS144 and methyl donor AdoMet. The results of the kinetic analyses revealed that the Clint values of the compounds could be strongly affected by the C-4 substitutions, which could be partially explained by the electronic effects of the C-4 substituents and the coordination modes of 7,8- dihydroxycoumarins in the active site of COMT. These findings provide helpful guidance for further structural modification of 7,8-DHCs to improve metabolic stability.
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Affiliation(s)
- Yang-Liu Xia
- Laboratory of Pharmacology & Toxicology, School of Life Science and Medicine, Dalian University of Technology, Panjin 124221, People's Republic of China
| | - Tong-Yi Dou
- Laboratory of Pharmacology & Toxicology, School of Life Science and Medicine, Dalian University of Technology, Panjin 124221, People's Republic of China
| | - Yong Liu
- Laboratory of Pharmacology & Toxicology, School of Life Science and Medicine, Dalian University of Technology, Panjin 124221, People's Republic of China
| | - Ping Wang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicines, Shanghai 201203, People's Republic of China
| | - Guang-Bo Ge
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicines, Shanghai 201203, People's Republic of China
| | - Ling Yang
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicines, Shanghai 201203, People's Republic of China
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Chen JJ, Zhang JX, Zhang XQ, Qi MJ, Shi MZ, Yang J, Zhang KZ, Guo C, Han YL. Effects of diosmetin on nine cytochrome P450 isoforms, UGTs and three drug transporters in vitro. Toxicol Appl Pharmacol 2017; 334:1-7. [DOI: 10.1016/j.taap.2017.08.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 08/23/2017] [Accepted: 08/30/2017] [Indexed: 11/29/2022]
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9
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Żołek T, Maciejewska D. Theoretical evaluation of ADMET properties for coumarin derivatives as compounds with therapeutic potential. Eur J Pharm Sci 2017; 109:486-502. [DOI: 10.1016/j.ejps.2017.08.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 08/29/2017] [Accepted: 08/30/2017] [Indexed: 11/16/2022]
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10
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Ning J, Louisse J, Spenkelink B, Wesseling S, Rietjens IMCM. Study on inter-ethnic human differences in bioactivation and detoxification of estragole using physiologically based kinetic modeling. Arch Toxicol 2017; 91:3093-3108. [PMID: 28357488 PMCID: PMC5562778 DOI: 10.1007/s00204-017-1941-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 02/21/2017] [Indexed: 12/21/2022]
Abstract
Considering the rapid developments in food safety in the past decade in China, it is of importance to obtain insight into what extent safety and risk assessments of chemicals performed for the Caucasian population apply to the Chinese population. The aim of the present study was to determine physiologically based kinetic (PBK) modeling-based predictions for differences between Chinese and Caucasians in terms of metabolic bioactivation and detoxification of the food-borne genotoxic carcinogen estragole. The PBK models were defined based on kinetic constants for hepatic metabolism derived from in vitro incubations using liver fractions of the two ethnic groups, and used to evaluate the inter-ethnic differences in metabolic activation and detoxification of estragole. The models predicted that at realistic dietary intake levels, only 0.02% of the dose was converted to the ultimate carcinogenic metabolite 1′-sulfooxyestragole in Chinese subjects, whereas this amounted to 0.09% of the dose in Caucasian subjects. Detoxification of 1′-hydroxyestragole, mainly via conversion to 1′-oxoestragole, was similar within the two ethnic groups. The 4.5-fold variation in formation of the ultimate carcinogenic metabolite of estragole accompanied by similar rates of detoxification may indicate a lower risk of estragole for the Chinese population at similar levels of exposure. The study provides a proof of principle for how PBK modeling can identify differences in ethnic sensitivity and provide a more refined risk assessment for a specific ethnic group for a compound of concern.
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Affiliation(s)
- Jia Ning
- Division of Toxicology, Wageningen University, Stippeneng 4, 6708 WE, Wageningen, The Netherlands.
| | - Jochem Louisse
- Division of Toxicology, Wageningen University, Stippeneng 4, 6708 WE, Wageningen, The Netherlands
| | - Bert Spenkelink
- Division of Toxicology, Wageningen University, Stippeneng 4, 6708 WE, Wageningen, The Netherlands
| | - Sebastiaan Wesseling
- Division of Toxicology, Wageningen University, Stippeneng 4, 6708 WE, Wageningen, The Netherlands
| | - Ivonne M C M Rietjens
- Division of Toxicology, Wageningen University, Stippeneng 4, 6708 WE, Wageningen, The Netherlands
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Gerstel D, Jacques-Jamin C, Schepky A, Cubberley R, Eilstein J, Grégoire S, Hewitt N, Klaric M, Rothe H, Duplan H. Comparison of protocols for measuring cosmetic ingredient distribution in human and pig skin. Toxicol In Vitro 2016; 34:153-160. [DOI: 10.1016/j.tiv.2016.03.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 03/08/2016] [Accepted: 03/23/2016] [Indexed: 11/28/2022]
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12
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Thiel C, Schneckener S, Krauss M, Ghallab A, Hofmann U, Kanacher T, Zellmer S, Gebhardt R, Hengstler JG, Kuepfer L. A Systematic Evaluation of the Use of Physiologically Based Pharmacokinetic Modeling for Cross-Species Extrapolation. J Pharm Sci 2015; 104:191-206. [DOI: 10.1002/jps.24214] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 09/22/2014] [Accepted: 09/22/2014] [Indexed: 01/06/2023]
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13
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Uchihashi S, Nishikawa M, Sakaki T, Ikushiro SI. The critical role of amino acid residue at position 117 of mouse UDP-glucuronosyltransfererase 1a6a and 1a6b in resveratrol glucuronidation. J Biochem 2012; 152:331-40. [DOI: 10.1093/jb/mvs078] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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14
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Alhusainy W, van den Berg SJPL, Paini A, Campana A, Asselman M, Spenkelink A, Punt A, Scholz G, Schilter B, Adams TB, van Bladeren PJ, Rietjens IMCM. Matrix Modulation of the Bioactivation of Estragole by Constituents of Different Alkenylbenzene-containing Herbs and Spices and Physiologically Based Biokinetic Modeling of Possible In Vivo Effects. Toxicol Sci 2012; 129:174-87. [DOI: 10.1093/toxsci/kfs196] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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15
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Wittgen HGM, van den Heuvel JJMW, van den Broek PHH, Siissalo S, Groothuis GMM, de Graaf IAM, Koenderink JB, Russel FGM. Transport of the coumarin metabolite 7-hydroxycoumarin glucuronide is mediated via multidrug resistance-associated proteins 3 and 4. Drug Metab Dispos 2012; 40:1076-9. [PMID: 22415933 DOI: 10.1124/dmd.111.044438] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Coumarin (1,2-benzopyrone) is a natural compound that has been used as a fragrance in the food and perfume industry and could have therapeutic usefulness in the treatment of lymphedema and different types of cancer. Several previous pharmacokinetic studies of coumarin have been performed in humans, which revealed extensive first-pass metabolism of the compound. 7-Hydroxycoumarin (7-HC) and its glucuronide (7-HC-G) are the main metabolites formed in humans, and via this route, 80 to 90% of the absorbed coumarin is excreted into urine, mainly as 7-HC-G. Active transport processes play a role in the urinary excretion of 7-HC-G; however, until now, the transporters involved remained to be elucidated. In this study, we investigated whether the efflux transporters multidrug resistance-associated proteins (MRP)1-4, breast cancer resistance protein, or P-glycoprotein play a role in 7-HC and 7-HC-G transport. For this purpose, we measured uptake of the metabolites into membrane vesicles overexpressing these transporters. Our results showed that 7-HC is not transported by any of the efflux transporters tested, whereas 7-HC-G was a substrate of MRP3 and MRP4. These results are in line with the pharmacokinetic profile of coumarin and suggest that MRP3 and MRP4 are the main transporters involved in the excretion of the coumarin metabolite 7-HC-G from liver and kidney.
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Affiliation(s)
- Hanneke G M Wittgen
- Department of Pharmacology and Toxicology, Radboud University Nijmegen Medical Centre, Nijmegen Centre for Molecular Life Sciences, Nijmegen, the Netherlands
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Jongeneelen F, ten Berge W. Simulation of urinary excretion of 1-hydroxypyrene in various scenarios of exposure to polycyclic aromatic hydrocarbons with a generic, cross-chemical predictive PBTK-model. Int Arch Occup Environ Health 2011; 85:689-702. [DOI: 10.1007/s00420-011-0713-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Accepted: 10/11/2011] [Indexed: 11/30/2022]
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17
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Yang CH, Tang L, Lv C, Ye L, Xia BJ, Hu M, Liu ZQ. Sulfation of selected mono-hydroxyflavones by sulfotransferases in vitro: a species and gender comparison. ACTA ACUST UNITED AC 2011; 63:967-70. [PMID: 21635263 DOI: 10.1111/j.2042-7158.2011.01298.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Sulfation via sulfotransferases is an important metabolic pathway contributing to the low bioavailability of flavonoids. This study aims to characterize the sulfation of mono-hydroxyflavones (MHFs) to obtain useful information on structure-metabolizing relationships in animal species and gender differences. METHODS Three representative MHFs, namely, 7-, 6- and 4'-MHF, were studied by incubating each MHF at different concentrations with various liver S9 fractions (mouse, rat, dog and human). KEY FINDINGS One mono-sulfate was identified for each MHF. 7-MHF and 4'-MHF usually have greater sulfations than 6-MHF. Regardless of whether the S9 fraction came from a male or female, there was a difference in sulfation in the species observed for all MHFs; the highest activity of sulfotransferases was in dog S9. Furthermore, gender differences affect sulfation of MHFs significantly. In rats, all sulfations for the three MHFs were higher in males than that in females while the opposite was observed in mice. CONCLUSIONS Regiospecific, species and gender dependence exist in the sulfonation of all selected MHFs.
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Affiliation(s)
- Cai Hua Yang
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, China
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18
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Alhusainy W, Paini A, Punt A, Louisse J, Spenkelink A, Vervoort J, Delatour T, Scholz G, Schilter B, Adams T, van Bladeren P, Rietjens I. Identification of nevadensin as an important herb-based constituent inhibiting estragole bioactivation and physiology-based biokinetic modeling of its possible in vivo effect. Toxicol Appl Pharmacol 2010; 245:179-90. [DOI: 10.1016/j.taap.2010.02.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2009] [Revised: 02/17/2010] [Accepted: 02/26/2010] [Indexed: 10/19/2022]
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19
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Liang SC, Ge GB, Liu HX, Zhang YY, Wang LM, Zhang JW, Yin L, Li W, Fang ZZ, Wu JJ, Li GH, Yang L. Identification and characterization of human UDP-glucuronosyltransferases responsible for the in vitro glucuronidation of daphnetin. Drug Metab Dispos 2010; 38:973-80. [PMID: 20176691 DOI: 10.1124/dmd.109.030734] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Daphnetin has been developed as an oral medicine for treatment of coagulation disorders and rheumatoid arthritis in China, but its in vitro metabolism remains unknown. In the present study, the UDP-glucuronosyltransferase (UGT) conjugation pathways of daphnetin were characterized. Two metabolites, 7-O-monoglucuronide daphnetin (M-1) and 8-O-monoglucuronide daphnetin (M-2), were identified by liquid chromatography/mass spectrometry and NMR when daphnetin was incubated, respectively, with liver microsomes from human (HLM), rat (RLM), and minipig (PLM) and human intestinal microsomes (HIM) in the presence of UDP-glucuronic acid. Screening assays with 12 human recombinant UGTs demonstrated that the formations of M-1 and M-2 were almost exclusively catalyzed by UGT1A9 and UGT1A6, whereas M-1 was formed to a minor extent by UGT1A3, 1A4, 1A7, 1A8, and 1A10 at a high substrate concentration. Kinetics studies, chemical inhibition, and correlation analysis were used to demonstrate that human UGT1A9 and UGT1A6 were major isoforms involved in the daphnetin glucuronidations in HLM and HIM. By in vitro-in vivo extrapolation of the kinetic data measured in HLM, the hepatic clearance and the corresponding hepatic extraction ratio were estimated to be 19.3 ml/min/kg b.wt. and 0.93, respectively, suggesting that human clearance of daphnetin via the glucuronidation is extensive. Chemical inhibition of daphnetin glucuronidation in HLM, RLM, and PLM showed large species differences although the metabolites were formed similarly among the species. In conclusion, the UGT conjugation pathways of daphnetin were fully elucidated and its C-8 phenol group was more selectively catalyzed by UGTs than by the C-7 phenol.
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Affiliation(s)
- Si-Cheng Liang
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
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Verreault J, Dietz R, Sonne C, Gebbink WA, Shahmiri S, Letcher RJ. Comparative fate of organohalogen contaminants in two top carnivores in Greenland: captive sledge dogs and wild polar bears. Comp Biochem Physiol C Toxicol Pharmacol 2008; 147:306-15. [PMID: 18248775 DOI: 10.1016/j.cbpc.2007.11.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Revised: 11/27/2007] [Accepted: 11/27/2007] [Indexed: 10/22/2022]
Abstract
The limited knowledge and/or the inability to control physiological condition parameters that influence the fate of organohalogen contaminants (OHCs) has been the foremost confounding aspect in monitoring programs and health risk assessments of wild top predators in the Arctic such as the polar bear (Ursus maritimus). In the present comparative study, we used a potential surrogate Canoidea species for the East Greenland polar bear, the captive sledge dog (Canis familiaris), to investigate some factors that may influence the bioaccumulation and biotransformation of major chlorinated and brominated OHCs in adipose tissue and blood (plasma) of control (fed commercial pork fat) and exposed (fed West Greenland minke whale (Balaenoptera acutorostrata) blubber) adult female sledge dogs. Furthermore, we compared the patterns and concentrations of OHCs and their known or suggested hydroxylated (OH) metabolites (e.g., OH-PCBs) in sledge dogs with those in adipose tissue and blood (plasma) of East Greenland adult female polar bears, and blubber of their main prey species, the ringed seal (Pusa hispida). The two-year feeding regime conducted with sledge dogs led to marked differences in overall adipose tissue (and plasma) OHC residue accumulation between the control and exposed groups. Characteristic prey-to-predator OHC bioaccumulation dynamics for major PCB and PBDE congeners (patterns and concentrations) and biotransformation capacity with respect to PCB metabolite formation and OH-PCB retention distinguished, to some extent, captive sledge dogs and wild polar bears. Based on the present findings, we conclude that the use of surrogate species in toxicological investigations for species in the Canoidea family should be done with great caution, although they remain essential in the context of contaminants research with sensitive arctic top carnivore species such as the polar bear.
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Affiliation(s)
- Jonathan Verreault
- National Wildlife Research Centre, Science and Technology Branch, Environment Canada, Carleton University, Ottawa, Ontario, Canada K1S 5B6
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Genetic Variations and Haplotypes of UDP-glucuronosyltransferase 1A Locus in a Korean Population. Ther Drug Monit 2008; 30:23-34. [DOI: 10.1097/ftd.0b013e3181633824] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Lahoz A, Donato MT, Montero S, Castell JV, Gómez-Lechón MJ. A new in vitro approach for the simultaneous determination of phase I and phase II enzymatic activities of human hepatocyte preparations. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2008; 22:240-244. [PMID: 18088071 DOI: 10.1002/rcm.3359] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Primary hepatocytes are still the best qualified in vitro system to anticipate drug metabolism in man. Recent advances in hepatocytes cryopreservation have notably increased their use not only for drug metabolism studies, but also for other applications such as cell transplantation. Evaluation of the drug-metabolizing competence of each hepatocytes preparation is needed. To date, the metabolic characterization of hepatocytes preparations relies on the assessment of phase I activities and the role of phase II enzymes receives little attention. A novel approach for the rapid assessment of the metabolic functionality of hepatocytes has been developed. A five-probe cocktail was used to simultaneously determine the enzymatic activities of major human phase I CYPs (CYP1A2, CYP2A6, CYP2C9, CYP2E1, CYP3A4), as well as two phase II enzymes: glucuronidase (UGTs) and sulfotransferase (SULT). Liquid chromatography/tandem mass spectrometry was used as the technique of choice for the determination of the enzymatic activities in a single run. Results showed that the method described herein permits a rapid assessment of the metabolic capabilities of human hepatocyte preparations as well as an estimation of the quality of freshly isolated or cryopreserved hepatocytes.
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Affiliation(s)
- Agustín Lahoz
- Unidad Mixta Fundación Hospital La Fe-Advancell, Avenida Campanar 21, Valencia, Spain.
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Somers GI, Lindsay N, Lowdon BM, Jones AE, Freathy C, Ho S, Woodrooffe AJM, Bayliss MK, Manchee GR. A Comparison of the Expression and Metabolizing Activities of Phase I and II Enzymes in Freshly Isolated Human Lung Parenchymal Cells and Cryopreserved Human Hepatocytes. Drug Metab Dispos 2007; 35:1797-805. [PMID: 17627976 DOI: 10.1124/dmd.107.015966] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The pulmonary and hepatic expression and catalytic activities of phase I and II drug-metabolizing enzymes were compared using human lung and liver tissue, and lung parenchymal cells (LPCs) and cryopreserved hepatocytes. Cytochrome P450 gene expression was generally lower in lung than in liver and CYP3A4 expression in lung was negligible. Esterase gene expression was similar in lung and liver. Expression of all sulfotransferase isoforms in lung was similar to or higher than that in liver. Lung tissue expressed low levels of UGT. However, the expression of UGT2A1 in lung was higher than that in liver. There was a range of catalytic activities in LPCs, including cytochrome P450, esterase, and sulfation pathways. Phase I activities were generally less than 10% of those determined in hepatocytes. Rates of ester hydrolysis and sulfation in LPCs were similar to those in hepatocytes. When measurable, glucuronidation in LPCs was present at very low levels, reflecting the gene expression data. The metabolism of salbutamol, formoterol, and budesonide was also investigated. Production of salbutamol-4-O-sulfate and budesonide oleate was observed in LPCs from at least two of three donor preparations studied. Formoterol sulfate and low levels of formoterol glucuronide were detected in one of three donors. In general, drug-metabolizing capability of LPCs is low compared with liver, although some evidence for substantial sulfation and deesterification capacity was observed. Therefore, these data support the use of this cell-based system for the investigation of key routes of xenobiotic metabolism in human lung parenchyma.
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Affiliation(s)
- G I Somers
- Drug Metabolism and Pharmacokinetics, Respiratory and Inflammation Centre of Excellence for Drug Discovery, GlaxoSmithKline, Stevenage, UK.
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