1
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Kingston E, Tingle M, Bellissima BL, Helsby N, Burns K. CYP-catalysed cycling of clozapine and clozapine- N-oxide promotes the generation of reactive oxygen species in vitro. Xenobiotica 2024; 54:26-37. [PMID: 38108307 DOI: 10.1080/00498254.2023.2294473] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 12/10/2023] [Indexed: 12/19/2023]
Abstract
Clozapine is an effective atypical antipsychotic indicated for treatment-resistant schizophrenia, but is under-prescribed due to the risk of severe adverse drug reactions such as myocarditis.A mechanistic understanding of clozapine cardiotoxicity remains elusive.This study aimed to investigate the contribution of selected CYP isoforms to cycling between clozapine and its major circulating metabolites, N-desmethylclozapine and clozapine-N-oxide, with the potential for reactive species production.CYP supersome™-based in vitro techniques were utilised to quantify specific enzyme activity associated with clozapine, clozapine-N-oxide and N-desmethylclozapine metabolism.The formation of reactive species within each incubation were quantified, and known intermediates detected.CYP3A4 predominately catalysed clozapine-N-oxide formation from clozapine and was associated with concentration-dependent reactive species production, whereas isoforms favouring the N-desmethylclozapine pathway (CYP2C19 and CYP1A2) did not produce reactive species.Extrahepatic isoforms CYP2J2 and CYP1B1 were also associated with the formation of clozapine-N-oxide and N-desmethylclozapine but did not favour one metabolic pathway over another.Unique to this investigation is that various CYP isoforms catalyse clozapine-N-oxide reduction to clozapine.This process was associated with the concentration-dependent formation of reactive species with CYP3A4, CYP1B1 and CYP1A1 that did not correlate with known reactive intermediates, implicating metabolite cycling and reactive oxygen species in the mechanism of clozapine-induced toxicity.
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Affiliation(s)
- Ellen Kingston
- Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Auckland, New Zealand
| | - Malcolm Tingle
- Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Auckland, New Zealand
| | - Brandi L Bellissima
- Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Auckland, New Zealand
| | - Nuala Helsby
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland, New Zealand
| | - Kathryn Burns
- Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Auckland, New Zealand
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2
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Kato R, Yamada T, Noda T, Tanaka S, Kohda Y, Ijiri Y. Mechanism of non-steroidal anti-androgen-induced liver injury: Reactive metabolites of flutamide and bicalutamide activate inflammasomes. Toxicol In Vitro 2023; 90:105606. [PMID: 37146920 DOI: 10.1016/j.tiv.2023.105606] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/10/2023] [Accepted: 04/27/2023] [Indexed: 05/07/2023]
Abstract
Flutamide is a non-steroidal anti-androgen agent, which is mainly used for the treatment of prostate cancer. Flutamide is known to cause severe adverse events, which includes idiosyncratic liver injury. However, details of the mechanism of these adverse reactions have not been elucidated. We investigated whether flutamide induces the release of damage-associated molecular patterns (DAMPs) that activate inflammasomes. We also tested bicalutamide, enzalutamide, apalutamide, and darolutamide for their ability to activate inflammasomes in differentiated THP-1 cells. The supernatant from the incubation of flutamide and bicalutamide with human hepatocarcinoma functional liver cell-4 (FLC-4) cells increased caspase-1 activity and production of IL-1ß by differentiated THP-1 cells. In the supernatant of FLC-4 cells with flutamide and bicalutamide, the heat shock protein (HSP) 40 or 60 was significantly increased. Addition of a carboxylesterase or a CYP inhibitor to the FLC-4 cells prevented release of HSPs from the FLC-4 cells. These results suggested that the reactive metabolites of flutamide and bicalutamide can cause the release of DAMPs from hepatocytes and activate inflammasomes. Inflammasome activation may be an important step in the activation of the immune system by flutamide or bicalutamide, which in some patients, can cause immune-related adverse events.
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Affiliation(s)
- Ryuji Kato
- Department of Cardiovascular Pharmacotherapy and Toxicology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Osaka 569-1094, Japan.
| | - Tomoyuki Yamada
- Department of Pharmacy, Osaka Medical and Pharmaceutical University Hospital, Osaka 569-8686, Japan
| | - Takumi Noda
- Department of Cardiovascular Pharmacotherapy and Toxicology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Osaka 569-1094, Japan
| | - Saori Tanaka
- Department of Pharmacotherapeutics, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Osaka 569-1094, Japan
| | - Yuka Kohda
- Department of Pharmacotherapeutics, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Osaka 569-1094, Japan
| | - Yoshio Ijiri
- Department of Cardiovascular Pharmacotherapy and Toxicology, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Osaka 569-1094, Japan
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3
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Chatterjee S, Makai S, Morandi B. Hydroxylamin‐abgeleitetes Reagenz als duales Oxidationsmittel und Aminogruppendonor für die eisenkatalysierte Herstellung von ungeschützten Sulfinamiden aus Thiolen. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202011138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Sayanti Chatterjee
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Deutschland
| | - Szabolcs Makai
- Laboratorium für Organische Chemie ETH Zürich Vladimir-Prelog-Weg 3, HCI 8093 Zürich Schweiz
| | - Bill Morandi
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim an der Ruhr Deutschland
- Laboratorium für Organische Chemie ETH Zürich Vladimir-Prelog-Weg 3, HCI 8093 Zürich Schweiz
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4
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Chatterjee S, Makai S, Morandi B. Hydroxylamine-Derived Reagent as a Dual Oxidant and Amino Group Donor for the Iron-Catalyzed Preparation of Unprotected Sulfinamides from Thiols. Angew Chem Int Ed Engl 2021; 60:758-765. [PMID: 32955152 PMCID: PMC7839456 DOI: 10.1002/anie.202011138] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Indexed: 11/10/2022]
Abstract
An iron catalyzed reaction for the selective transformation of thiols (-SH) to sulfinamides (-SONH2 ) by a direct transfer of -O and free -NH2 groups has been developed. The reaction operates under mild conditions using a bench stable hydroxylamine derived reagent, exhibits broad functional group tolerance, is scalable and proceeds without the use of any precious metal catalyst or additional oxidant. This novel, practical reaction leads to the formation of two distinct new bonds (S=O and S-N) in a single step to chemoselectively form valuable, unprotected sulfinamide products. Preliminary mechanistic studies implicate the role of the alcoholic solvent as an oxygen atom donor.
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Affiliation(s)
- Sayanti Chatterjee
- Max-Planck-Institut für KohlenforschungKaiser-Wihelm-Platz 145470Mülheim an der RuhrGermany
| | - Szabolcs Makai
- Laboratorium für Organische ChemieETH ZürichVladimir-Prelog-Weg 3, HCI8093ZürichSwitzerland
| | - Bill Morandi
- Max-Planck-Institut für KohlenforschungKaiser-Wihelm-Platz 145470Mülheim an der RuhrGermany
- Laboratorium für Organische ChemieETH ZürichVladimir-Prelog-Weg 3, HCI8093ZürichSwitzerland
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5
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Dang NL, Matlock MK, Hughes TB, Swamidass SJ. The Metabolic Rainbow: Deep Learning Phase I Metabolism in Five Colors. J Chem Inf Model 2020; 60:1146-1164. [DOI: 10.1021/acs.jcim.9b00836] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Na Le Dang
- Department of Pathology and Immunology, Washington University School of Medicine, Campus Box 8118, 660 S. Euclid Ave., St. Louis, Missouri 63110, United States
| | - Matthew K. Matlock
- Department of Pathology and Immunology, Washington University School of Medicine, Campus Box 8118, 660 S. Euclid Ave., St. Louis, Missouri 63110, United States
| | - Tyler B. Hughes
- Department of Pathology and Immunology, Washington University School of Medicine, Campus Box 8118, 660 S. Euclid Ave., St. Louis, Missouri 63110, United States
| | - S. Joshua Swamidass
- Department of Pathology and Immunology, Washington University School of Medicine, Campus Box 8118, 660 S. Euclid Ave., St. Louis, Missouri 63110, United States
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6
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Mei H, Liu J, Pajkert R, Röschenthaler GV, Han J. A Selectfluor-promoted oxidative reaction of disulfides and amines: access to sulfinamides. Org Biomol Chem 2020; 18:3761-3766. [DOI: 10.1039/d0ob00720j] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
An unprecedented metal-free oxidative reaction of disulfides and amines with Selectfluor as a mild oxidant under aerobic conditions was developed.
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Affiliation(s)
- Haibo Mei
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources
- College of Chemical Engineering
- Nanjing Forestry University
- Nanjing 210037
- China
| | - Jiang Liu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources
- College of Chemical Engineering
- Nanjing Forestry University
- Nanjing 210037
- China
| | - Romana Pajkert
- Department of Life Sciences and Chemistry
- Jacobs University Bremen gGmbH
- 28759 Bremen
- Germany
| | | | - Jianlin Han
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources
- College of Chemical Engineering
- Nanjing Forestry University
- Nanjing 210037
- China
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7
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Fan H, Zhang A, Liao C, Yang Y, Zhang L, Liu J, Xia Y, Si D, Dong S, Liu C. In vitro metabolism and in vivo pharmacokinetics of bentysrepinine (Y101), an investigational new drug for anti-HBV-infected hepatitis: focus on interspecies comparison. Xenobiotica 2019; 50:468-478. [PMID: 31329010 DOI: 10.1080/00498254.2019.1646946] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The objective of this study was to clarify the species differences of pharmacokinetics of Y101 (N-[N-benzoyl-O-(2-dimethylaminoethyl)-l-tyrosyl]-l-phenylalaninol hydrochloride), a derivative of herbal ingredient with anti-HBV hepatitis activity, in rats, dogs, monkeys and humans.The metabolic stability and metabolite identification studies using liver microsomes in vitro, plasma protein binding using a rapid equilibrium dialysis in vitro, pharmacokinetic studies in vivo were carried out to evaluate the interspecies differences. The toxicokinetic study in monkeys was also investigated.The metabolic profiles were similar in monkeys and humans, which were significant different from rats and dogs in vitro. In vitro plasma protein binding showed no major differences between species with medium to high protein binding rates. After single oral dose to rats, dogs, and monkeys, the absolute oral bioavailability of Y101 was 44.9%, 43.1%, and 19.2%, respectively. There was no accumulation for Y101 toxicokinetics in monkeys after oral administration for 90 d.The metabolic profiles indicated monkey was the very animal model for preclinical safety evaluation of Y101. Our results have demonstrated the favorable pharmacokinetics profile of Y101, which supports the clinical trials in humans.
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Affiliation(s)
- Huirong Fan
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - Aijie Zhang
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - Cuiping Liao
- Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yuanhui Yang
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - Lihua Zhang
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - Jianfeng Liu
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - Yuanyuan Xia
- State Key Laboratory of Drug Delivery Technology and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin, China
| | - Duanyun Si
- State Key Laboratory of Drug Delivery Technology and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin, China
| | - Shiqi Dong
- Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
| | - Changxiao Liu
- State Key Laboratory of Drug Delivery Technology and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin, China
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8
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Tamura R, Balabanova A, Frakes SA, Bargmann A, Grimm J, Koch TH, Yin H. Photoactivatable Prodrug of Doxazolidine Targeting Exosomes. J Med Chem 2019; 62:1959-1970. [PMID: 30703330 DOI: 10.1021/acs.jmedchem.8b01508] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Natural lipid nanocarriers, exosomes, carry cell-signaling materials such as DNA and RNA for intercellular communications. Exosomes derived from cancer cells contribute to the progression and metastasis of cancer cells by transferring oncogenic signaling molecules to neighboring and remote premetastatic sites. Therefore, applying the unique properties of exosomes for cancer therapy has been expected in science, medicine, and drug discovery fields. Herein, we report that an exosome-targeting prodrug system, designated MARCKS-ED-photodoxaz, could spatiotemporally control the activation of an exquisitely cytotoxic agent, doxazolidine (doxaz), with UV light. The MARCKS-ED peptide enters a cell by forming a complex with the exosomes in situ at its plasma membrane and in the media. MARCKS-ED-photodoxaz releases doxaz under near-UV irradiation to inhibit cell growth with low nanomolar IC50 values. The MARCKS-ED-photodoxaz system targeting exosomes and utilizing photochemistry will potentially provide a new approach for the treatment of cancer, especially for highly progressive and invasive metastatic cancers.
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Affiliation(s)
- Ryo Tamura
- Molecular Pharmacology Program , Memorial Sloan Kettering Cancer Center , New York , New York 10065 , United States
| | | | | | | | - Jan Grimm
- Molecular Pharmacology Program , Memorial Sloan Kettering Cancer Center , New York , New York 10065 , United States
| | | | - Hang Yin
- School of Pharmaceutical Sciences, Tsinghua University-Peking University Joint Center for Life Sciences , Tsinghua University , Beijing 100082 , China
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9
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Machine Learning Models for the Prediction of Chemotherapy-Induced Peripheral Neuropathy. Pharm Res 2019; 36:35. [DOI: 10.1007/s11095-018-2562-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 12/17/2018] [Indexed: 01/01/2023]
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10
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Low YS, Alves VM, Fourches D, Sedykh A, Andrade CH, Muratov EN, Rusyn I, Tropsha A. Chemistry-Wide Association Studies (CWAS): A Novel Framework for Identifying and Interpreting Structure-Activity Relationships. J Chem Inf Model 2018; 58:2203-2213. [PMID: 30376324 DOI: 10.1021/acs.jcim.8b00450] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Quantitative structure-activity relationships (QSAR) models are often seen as a "black box" because they are considered difficult to interpret. Meanwhile, qualitative approaches, e.g., structural alerts (SA) or read-across, provide mechanistic insight, which is preferred for regulatory purposes, but predictive accuracy of such approaches is often low. Herein, we introduce the chemistry-wide association study (CWAS) approach, a novel framework that both addresses such deficiencies and combines advantages of statistical QSAR and alert-based approaches. The CWAS framework consists of the following steps: (i) QSAR model building for an end point of interest, (ii) identification of key chemical features, (iii) determination of communities of such features disproportionately co-occurring more frequently in the active than in the inactive class, and (iv) assembling these communities to form larger (and not necessarily chemically connected) novel structural alerts with high specificity. As a proof-of-concept, we have applied CWAS to model Ames mutagenicity and Stevens-Johnson Syndrome (SJS). For the well-studied Ames mutagenicity data set, we identified 76 important individual fragments and assembled co-occurring fragments into SA both replicative of known as well as representing novel mutagenicity alerts. For the SJS data set, we identified 29 important fragments and assembled co-occurring communities into SA including both known and novel alerts. In summary, we demonstrate that CWAS provides a new framework to interpret predictive QSAR models and derive refined structural alerts for more effective design and safety assessment of drugs and drug candidates.
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Affiliation(s)
- Yen S Low
- Laboratory for Molecular Modeling, UNC Eshelman School of Pharmacy , University of North Carolina , Chapel Hill , North Carolina 27599 , United States
| | - Vinicius M Alves
- Laboratory for Molecular Modeling, UNC Eshelman School of Pharmacy , University of North Carolina , Chapel Hill , North Carolina 27599 , United States.,Laboratory for Molecular Modeling and Design, Department of Pharmacy , Federal University of Goias , Goiania , Goias 74605-170 , Brazil
| | - Denis Fourches
- Department of Chemistry and Bioinformatics Research Center , North Carolina State University , Raleigh , North Carolina 27695 , United States
| | - Alexander Sedykh
- Sciome LLC , Research Triangle Park , North Carolina 27709 , United States
| | - Carolina Horta Andrade
- Laboratory for Molecular Modeling and Design, Department of Pharmacy , Federal University of Goias , Goiania , Goias 74605-170 , Brazil
| | - Eugene N Muratov
- Laboratory for Molecular Modeling, UNC Eshelman School of Pharmacy , University of North Carolina , Chapel Hill , North Carolina 27599 , United States.,Department of Chemical Technology , Odessa National Polytechnic University , Odessa 65000 , Ukraine
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences , Texas A&M University , College Station , Texas 77843 , United States
| | - Alexander Tropsha
- Laboratory for Molecular Modeling, UNC Eshelman School of Pharmacy , University of North Carolina , Chapel Hill , North Carolina 27599 , United States
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11
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Affiliation(s)
- Balaswamy Reddy
- 1 Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bengaluru, India
| | - Soumitra Das
- 1 Department of Psychiatry, National Institute of Mental Health and Neurosciences, Bengaluru, India
| | - Udairaj B
- 2 Department of Dermatology, ESIC Hospital Peenya, Bengaluru, India
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12
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Godinho ALA, Martins IL, Nunes J, Charneira C, Grilo J, Silva DM, Pereira SA, Soto K, Oliveira MC, Marques MM, Jacob CC, Antunes AMM. High resolution mass spectrometry-based methodologies for identification of Etravirine bioactivation to reactive metabolites: In vitro and in vivo approaches. Eur J Pharm Sci 2018; 119:70-82. [PMID: 29592839 DOI: 10.1016/j.ejps.2018.03.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 02/28/2018] [Accepted: 03/22/2018] [Indexed: 01/16/2023]
Abstract
Drug bioactivation to reactive metabolites capable of covalent adduct formation with bionucleophiles is a major cause of drug-induced adverse reactions. Therefore, elucidation of reactive metabolites is essential to unravel the toxicity mechanisms induced by drugs and thereby identify patient subgroups at higher risk. Etravirine (ETR) was the first second-generation Non-Nucleoside Reverse Transcriptase Inhibitor (NNRTI) to be approved, as a therapeutic option for HIV-infected patients who developed resistance to the first-generation NNRTIs. Additionally, ETR came into market aiming to overcome some adverse effects associated with the previously used efavirenz (neurotoxicity) and nevirapine (hepatotoxicity) therapies. Nonetheless, post-marketing reports of severe ETR-induced skin rash and hypersensitivity reactions have prompted the U.S. FDA to issue a safety alert on ETR. Taking into consideration that ETR usage may increase in the near future, due to the possible use of the drug for coinfection with malaria and HIV, the development of reliable prognostic tools for early risk/benefit estimations is urgent. In the current study, high resolution mass spectrometry-based methodologies were integrated with MS3 experiments for the identification of reactive ETR metabolites/adducts: 1) in vitro incubation of the drug with human and rat liver S9 fractions in the presence of Phase I and II co-factors, including glutathione, as a trapping bionucleophile; and 2) in vivo, using urine samples from HIV-infected patients on ETR therapy. We obtained evidence for multiple bioactivation pathways leading to the formation of covalent adducts with glutathione and N-acetyl-L-cysteine. These results suggest that similar reactions may occur with cysteine residues of proteins, supporting a role for ETR bioactivation in the onset of the toxic effects elicited by the drug. Additionally, ETR metabolites stemming from amine oxidation, with potential toxicological significance, were identified in vitro and in vivo. Also noteworthy is the fact that new metabolic conjugation pathways of glucuronide metabolites were demonstrated for the first time, raising questions about their potential toxicological implications. In conclusion, these results represent not only a contribution towards the elucidation of new metabolic pathways of drugs in general but also an important step towards the elucidation of potentially toxic ETR pathways, whose understanding may be crucial for reliable risk/benefit estimations of ETR-based regimens.
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Affiliation(s)
- Ana L A Godinho
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Inês L Martins
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - João Nunes
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Catarina Charneira
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Jorge Grilo
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal
| | - Diogo M Silva
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Sofia A Pereira
- CEDOC, Chronic Diseases Research Centre, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, 1169-006 Lisboa, Portugal
| | - Karina Soto
- Hospital Prof. Doutor Fernando Fonseca E.P.E., IC 19, 2720-276 Amadora, Portugal
| | - M Conceição Oliveira
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - M Matilde Marques
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal
| | - Cristina C Jacob
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
| | - Alexandra M M Antunes
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal.
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13
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Choi JS, Kim CS, Berdis A. Inhibition of Translesion DNA Synthesis as a Novel Therapeutic Strategy to Treat Brain Cancer. Cancer Res 2017; 78:1083-1096. [PMID: 29259011 DOI: 10.1158/0008-5472.can-17-2464] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 10/30/2017] [Accepted: 12/12/2017] [Indexed: 11/16/2022]
Abstract
Temozolomide is a DNA-alkylating agent used to treat brain tumors, but resistance to this drug is common. In this study, we provide evidence that efficacious responses to this drug can be heightened significantly by coadministration of an artificial nucleoside (5-nitroindolyl-2'-deoxyriboside, 5-NIdR) that efficiently and selectively inhibits the replication of DNA lesions generated by temozolomide. Conversion of this compound to the corresponding nucleoside triphosphate, 5-nitroindolyl-2'-deoxyriboside triphosphate, in vivo creates a potent inhibitor of several human DNA polymerases that can replicate damaged DNA. Accordingly, 5-NIdR synergized with temozolomide to increase apoptosis of tumor cells. In a murine xenograft model of glioblastoma, whereas temozolomide only delayed tumor growth, its coadministration with 5-NIdR caused complete tumor regression. Exploratory toxicology investigations showed that high doses of 5-NIdR did not produce the side effects commonly seen with conventional nucleoside analogs. Collectively, our results offer a preclinical pharmacologic proof of concept for the coordinate inhibition of translesion DNA synthesis as a strategy to improve chemotherapeutic responses in aggressive brain tumors.Significance: Combinatorial treatment of glioblastoma with temozolomide and a novel artificial nucleoside that inhibits replication of damaged DNA can safely enhance therapeutic responses. Cancer Res; 78(4); 1083-96. ©2017 AACR.
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Affiliation(s)
- Jung-Suk Choi
- Department of Chemistry, Cleveland State University, Cleveland, Ohio
| | - Casey Seol Kim
- Department of Biological, Geological, and Environmental Sciences, Cleveland State University, Cleveland, Ohio
| | - Anthony Berdis
- Department of Chemistry, Cleveland State University, Cleveland, Ohio. .,Department of Biological, Geological, and Environmental Sciences, Cleveland State University, Cleveland, Ohio.,Center for Gene Regulation in Health and Disease, Cleveland State University, Cleveland, Ohio.,Case Comprehensive Cancer Center, Cleveland, Ohio
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14
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Rabelo VWH, Romeiro NC, Abreu PA. Design strategies of oxidosqualene cyclase inhibitors: Targeting the sterol biosynthetic pathway. J Steroid Biochem Mol Biol 2017; 171:305-317. [PMID: 28479228 DOI: 10.1016/j.jsbmb.2017.05.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 04/29/2017] [Accepted: 05/04/2017] [Indexed: 01/04/2023]
Abstract
Targeting the sterol biosynthesis pathway has been explored for the development of new bioactive compounds. Among the enzymes of this pathway, oxidosqualene cyclase (OSC) which catalyzes lanosterol cyclization from 2,3-oxidosqualene has emerged as an attractive target. In this work, we reviewed the most promising OSC inhibitors from different organisms and their potential for the development of new antiparasitic, antifungal, hypocholesterolemic and anticancer drugs. Different strategies have been adopted for the discovery of new OSC inhibitors, such as structural modifications of the natural substrate or the reaction intermediates, the use of the enzyme's structural information to discover compounds with novel chemotypes, modifications of known inhibitors and the use of molecular modeling techniques such as docking and virtual screening to search for new inhibitors. This review brings new perspectives on structural insights of OSC from different organisms and reveals the broad structural diversity of OSC inhibitors which may help evidence lead compounds for further investigations with various therapeutic applications.
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Affiliation(s)
- Vitor Won-Held Rabelo
- Laboratório de Modelagem Molecular e Pesquisa em Ciências Farmacêuticas, LaMCiFar, Universidade Federal do Rio de Janeiro - Campus Macaé, Av. São José do Barreto, Macaé 27965-045, RJ, Brazil; Programa de Pós-Graduação em Produtos Bioativos e Biociências, Universidade Federal do Rio de Janeiro, Campus Macaé Professor Aloísio Teixeira, Macaé, RJ, Brazil
| | - Nelilma Correia Romeiro
- Laboratório Integrado de Computação Científica, LICC, Universidade Federal do Rio de Janeiro, Campus Macaé, Macaé, RJ, 27965-045, Brazil
| | - Paula Alvarez Abreu
- Laboratório de Modelagem Molecular e Pesquisa em Ciências Farmacêuticas, LaMCiFar, Universidade Federal do Rio de Janeiro - Campus Macaé, Av. São José do Barreto, Macaé 27965-045, RJ, Brazil.
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15
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Abstract
A number of drugs have been withdrawn from the market or severely restricted in their use because of unexpected toxicities that become apparent only after the launch of new drug entities. Circumstantial evidence suggests that, in most cases, reactive metabolites are responsible for these unexpected toxicities. In this review, a general overview of the types of reactive metabolites and the consequences of their formation are presented. The current approaches to evaluate bioactivation potential of new compounds with particular emphasis on the advantages and limitation of these procedures will be discussed. Reasonable reasons for the excellent safety record of certain drugs susceptible to bioactivation will also be explored and should provide valuable guidance in the use of reactive-metabolite assessments when nominating drug candidates for development. This will, in turn, help us to design and bring safer drugs to the market.
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Affiliation(s)
- Sabry M Attia
- Department of Pharmacology and Toxicology; College of Pharmacy; King Saud University; Riyadh, Saudi Arabia.
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16
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Low YS, Caster O, Bergvall T, Fourches D, Zang X, Norén GN, Rusyn I, Edwards R, Tropsha A. Cheminformatics-aided pharmacovigilance: application to Stevens-Johnson Syndrome. J Am Med Inform Assoc 2015; 23:968-78. [PMID: 26499102 PMCID: PMC4997030 DOI: 10.1093/jamia/ocv127] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 07/11/2015] [Indexed: 11/21/2022] Open
Abstract
Objective
Quantitative Structure-Activity Relationship (QSAR) models can predict adverse drug reactions (ADRs), and thus provide early warnings of potential hazards. Timely identification of potential safety concerns could protect patients and aid early diagnosis of ADRs among the exposed. Our objective was to determine whether global spontaneous reporting patterns might allow chemical substructures associated with Stevens-Johnson Syndrome (SJS) to be identified and utilized for ADR prediction by QSAR models.
Materials and Methods
Using a reference set of 364 drugs having positive or negative reporting correlations with SJS in the VigiBase global repository of individual case safety reports (Uppsala Monitoring Center, Uppsala, Sweden), chemical descriptors were computed from drug molecular structures. Random Forest and Support Vector Machines methods were used to develop QSAR models, which were validated by external 5-fold cross validation. Models were employed for virtual screening of DrugBank to predict SJS actives and inactives, which were corroborated using knowledge bases like VigiBase, ChemoText, and MicroMedex (Truven Health Analytics Inc, Ann Arbor, Michigan).
Results
We developed QSAR models that could accurately predict if drugs were associated with SJS (area under the curve of 75%–81%). Our 10 most active and inactive predictions were substantiated by SJS reports (or lack thereof) in the literature.
Discussion
Interpretation of QSAR models in terms of significant chemical descriptors suggested novel SJS structural alerts.
Conclusions
We have demonstrated that QSAR models can accurately identify SJS active and inactive drugs. Requiring chemical structures only, QSAR models provide effective computational means to flag potentially harmful drugs for subsequent targeted surveillance and pharmacoepidemiologic investigations.
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Affiliation(s)
- Yen S Low
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina, USA Department of Environmental Sciences and Engineering, Gillings School of Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Ola Caster
- Uppsala Monitoring Centre, Uppsala, Sweden Department of Computer and Systems Sciences, Stockholm University, Kista, Sweden
| | | | - Denis Fourches
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Xiaoling Zang
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina, USA
| | - G Niklas Norén
- Uppsala Monitoring Centre, Uppsala, Sweden Department of Mathematics, Stockholm University, Stockholm, Sweden
| | - Ivan Rusyn
- Department of Environmental Sciences and Engineering, Gillings School of Public Health, University of North Carolina, Chapel Hill, North Carolina, USA
| | | | - Alexander Tropsha
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina, USA
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17
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Association of decreased mRNA expression of multidrug and toxin extrusion protein 1 in peripheral blood cells with the development of flutamide-induced liver injury. Cancer Chemother Pharmacol 2015; 75:1191-7. [DOI: 10.1007/s00280-015-2743-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 03/31/2015] [Indexed: 11/26/2022]
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18
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Ng W, Metushi IG, Uetrecht J. Hepatic effects of aminoglutethimide: A model aromatic amine. J Immunotoxicol 2013; 12:24-32. [DOI: 10.3109/1547691x.2013.867912] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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19
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Ng W, Uetrecht J. Effect of Aminoglutethimide on Neutrophils in Rats: Implications for Idiosyncratic Drug-Induced Blood Dyscrasias. Chem Res Toxicol 2013; 26:1272-81. [DOI: 10.1021/tx400224j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Winnie Ng
- Department
of Pharmaceutical
Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada M5S 3M2
| | - Jack Uetrecht
- Department
of Pharmaceutical
Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada M5S 3M2
- Department of Pharmacology and
Toxicology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada M5S 1A8
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20
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Ng W, Uetrecht J. Changes in gene expression induced by aromatic amine drugs: Testing the danger hypothesis. J Immunotoxicol 2012; 10:178-91. [DOI: 10.3109/1547691x.2012.707699] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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21
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Ng W, Lobach AR, Zhu X, Chen X, Liu F, Metushi IG, Sharma A, Li J, Cai P, Ip J, Novalen M, Popovic M, Zhang X, Tanino T, Nakagawa T, Li Y, Uetrecht J. Animal Models of Idiosyncratic Drug Reactions. CURRENT CONCEPTS IN DRUG METABOLISM AND TOXICOLOGY 2012; 63:81-135. [DOI: 10.1016/b978-0-12-398339-8.00003-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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22
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23
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24
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Affiliation(s)
- Graham F Smith
- Central Chemistry Team Lead, Merck Research Laboratories, Boston, 33 Avenue Louis Pasteur, Boston, MA 02115, USA
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25
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Yang M, Chordia MD, Li F, Huang T, Linden J, Macdonald TL. Neutrophil- and Myeloperoxidase-Mediated Metabolism of Reduced Nimesulide: Evidence for Bioactivation. Chem Res Toxicol 2010; 23:1691-700. [DOI: 10.1021/tx1001496] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Min Yang
- Department of Chemistry and Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Mahendra D. Chordia
- Department of Chemistry and Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Fengping Li
- Department of Chemistry and Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Tao Huang
- Department of Chemistry and Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Joel Linden
- Department of Chemistry and Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Timothy L. Macdonald
- Department of Chemistry and Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia 22904, United States
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26
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Feng J, Sun J, Wang MZ, Zhang Z, Kim ST, Zhu Y, Sun J, Xu J. Compilation of a comprehensive gene panel for systematic assessment of genes that govern an individual’s drug responses. Pharmacogenomics 2010; 11:1403-25. [DOI: 10.2217/pgs.10.99] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Aims: Polymorphisms of genes involved in the pharmacokinetic and pharmacodynamic processes underlie the divergent drug responses among individuals. Despite some successes in identifying these polymorphisms, the candidate gene approach suffers from insufficient gene coverage whereas the genome-wide association approach is limited by less than ideal coverage of SNPs in some important genes. To expand the potential of the candidate approach, we aim to delineate a comprehensive network of drug-response genes for in-depth genetic studies. Materials & methods: Pharmacologically important genes were extracted from various sources including literatures and web resources. These genes, along with their homologs and regulatory miRNAs, were organized based on their pharmacological functions and weighted by literature evidence and confidence levels. Their coverage was evaluated by analyzing three commercial SNP chips commonly used for genome-wide association studies: Affymetrix SNP array 6.0, Illumina HumanHap1M and Illumina Omni. Results: A panel of drug-response genes was constructed, which contains 923 pharmacokinetic genes, 703 pharmacodynamic genes and 720 miRNAs. There are only 16.7% of these genes whose all known SNPs can be directly or indirectly (r2 > 0.8) captured by the SNP chips with coverage of more than 80%. This is possibly because these SNPs chips have notably poor performance over rare SNPs and miRNA genes. Conclusion: We have compiled a panel of candidate genes that may be pharmacologically important. Using this knowledgebase, we are able to systematically evaluate genes and their variants that govern an individual’s response to a given pharmaceutical therapy. This approach can serve as a necessary complement to genome-wide associations.
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Affiliation(s)
- Junjie Feng
- Center for Cancer Genomics, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Jielin Sun
- Center for Cancer Genomics, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Michael Zhuo Wang
- Division of Pharmacotherapy & Experimental Therapeutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, NC, USA
| | - Zheng Zhang
- Center for Cancer Genomics, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Seong-Tae Kim
- Center for Cancer Genomics, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Yi Zhu
- Center for Cancer Genomics, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Jishan Sun
- Center for Cancer Genomics, Wake Forest University School of Medicine, Winston-Salem, NC, USA
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27
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Abstract
The danger hypothesis has had a profound effect on the way immunologists view the immune response. This hypothesis proposes that the major determinant of whether an immune response is mounted against some agent is determined by whether that agent causes some type of cell damage. Assuming that most idiosyncratic drug reactions (IDRs) are immune-mediated, this hypothesis also has the potential to explain many aspects of the mechanism of these adverse drug reactions. For example, most IDRs appear to be caused by chemical metabolites rather than the parent drug, but not all drugs that form reactive metabolites are associated with a significant incidence of IDRs. Therefore, using the danger hypothesis, one feature of a drug candidate that may predict whether it causes an IDR is whether the drug, or more likely its reactive metabolites, cause cell damage. Although the range of molecules that can act as danger signals is unknown, the most attractive candidates are high mobility group box 1 protein (HMGB1), heat shock proteins, and S100 proteins. These molecules act through the same receptors (toll-like receptors) as pathogen-associated molecules that stimulate the immune system. Therefore, other environmental factors such as infections or trauma might determine which patients would be at increased risk for IDRs. Although there are examples where this appears to be the case, in most cases there are no obvious environmental factors that determine IDR risk. In addition, in animal models of immune-mediated reactions, stimulation of toll-like receptors often does not increase the immune response, and depending on the timing, it can actually be protective. Therefore, there may be additional unknown control mechanisms that are involved. A better understanding of these fundamental immune mechanisms has the potential to have a significant impact on many areas of medicine.
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28
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Fries A, Winkler R, Hertweck C. Structural and biochemical basis for the firm chemo- and regioselectivity of the nitro-forming N-oxygenase AurF. Chem Commun (Camb) 2010; 46:7760-2. [DOI: 10.1039/c0cc02811h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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29
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Griffith DA, Hadcock JR, Black SC, Iredale PA, Carpino PA, DaSilva-Jardine P, Day R, DiBrino J, Dow RL, Landis MS, O'Connor RE, Scott DO. Discovery of 1-[9-(4-chlorophenyl)-8-(2-chlorophenyl)-9H-purin-6-yl]-4-ethylaminopiperidine-4-carboxylic acid amide hydrochloride (CP-945,598), a novel, potent, and selective cannabinoid type 1 receptor antagonist. J Med Chem 2009; 52:234-7. [PMID: 19102698 DOI: 10.1021/jm8012932] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report the structure-activity relationships, design, and synthesis of the novel cannabinoid type 1 (CB1) receptor antagonist 3a (CP-945,598). Compound 3a showed subnanomolar potency at human CB1 receptors in binding (Ki = 0.7 nM) and functional assays (Ki = 0.12 nM). In vivo, compound 3a reversed cannabinoid agonist-mediated responses, reduced food intake, and increased energy expenditure and fat oxidation in rodents.
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Affiliation(s)
- David A Griffith
- Department of Cardiovascular, Metabolic, and Endocrine Diseases, Pfizer Global Research and Development, Groton, Connecticut 06340, USA.
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30
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Redox-active dinitrodiphenylthioethers against Leishmania: synthesis, structure-activity relationships and mechanism of action studies. Bioorg Med Chem 2008; 17:820-9. [PMID: 19058972 DOI: 10.1016/j.bmc.2008.11.031] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Revised: 11/11/2008] [Accepted: 11/13/2008] [Indexed: 11/24/2022]
Abstract
BTB 06237 (2-[(2,4-dichloro-5-methylphenyl)sulfanyl]-1,3-dinitro-5-(trifluoromethyl) benzene), a compound previously identified through QSAR pharmacophore development and a virtual screen of the Maybridge database, possesses potent and selective activity against Leishmania parasites. In the present study, several analogs of BTB 06237 were synthesized and analyzed for activity against Leishmania axenic amastigotes, their ability to reduce the level of parasitemia in peritoneal macrophages, and their ability to generate reactive oxygen species (ROS) in L. donovani promastigotes. It was found that an aromatic ring must be present in the position occupied by the 2,4-dichloro-5-methylphenyl group in the lead compound, but changing the functional groups generally has little effect on the antileishmanial potency. Alterations to the 1,3-dinitro-5-(trifluoromethyl)benzene ring have more influence on antiparasitic activity with two aromatic nitro groups and a third electron-withdrawing group being required. This structural requirement corresponds with redox potential, the ability to generate ROS in the parasites, and dissipation of the mitochondrial membrane potential. Finally, we used this collection of data to design a new antileishmanial compound with strong activity in vitro and improved properties as an antileishmanial candidate.
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31
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Uetrecht J. Evaluation of Which Reactive Metabolite, If Any, Is Responsible for a Specific Idiosyncratic Reaction. Drug Metab Rev 2008; 38:745-53. [PMID: 17145699 DOI: 10.1080/03602530600959615] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Reactive metabolites are believed to be responsible for most idiosyncratic drug reactions. It is often assumed that if a reactive metabolite is found, it must be responsible for the idiosyncratic reactions associated with that drug. However, the evidence linking reactive metabolites and idiosyncratic reactions is circumstantial at best, and in many cases we have virtually no evidence. Furthermore, it is common for a drug to form several reactive metabolites, so it can be difficult to determine which, if any, is responsible for a given idiosyncratic reaction. Although the reactive metabolite hypothesis is logical, it has important implications for drug development, and we need to develop ways to test the hypothesis for specific drugs rigorously. Valid animal models are a powerful tool for testing whether a specific reactive metabolite is responsible for a specific adverse reaction and for studying further the mechanism by which it may induce such reactions; however, such models are rare.
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Affiliation(s)
- Jack Uetrecht
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada.
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32
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Ohbuchi M, Miyata M, Nagai D, Shimada M, Yoshinari K, Yamazoe Y. Role of Enzymatic N-Hydroxylation and Reduction in Flutamide Metabolite-Induced Liver Toxicity. Drug Metab Dispos 2008; 37:97-105. [DOI: 10.1124/dmd.108.021964] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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33
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Uetrecht J. Idiosyncratic drug reactions: past, present, and future. Chem Res Toxicol 2007; 21:84-92. [PMID: 18052104 DOI: 10.1021/tx700186p] [Citation(s) in RCA: 177] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Although the major working hypothesis for the mechanism of idiosyncratic drug reactions (IDRs), the hapten hypothesis, has not changed since 1987, several hypotheses have been added, for example, the danger hypothesis and the pharmaceutical interaction hypothesis. Genetic studies have found that several IDRs are linked to specific HLA genes, providing additional evidence that they are immune-mediated. Evidence that most IDRs are caused by reactive metabolites has led pharmaceutical companies to avoid drug candidates that form significant amounts of reactive metabolites; however, at least one IDR, ximelagatran-induced liver toxicity, does not appear to be caused by a reactive metabolite. It is possible that there are biomarkers such as those related to cell stress that would predict that a drug candidate would cause a significant incidence of IDRs; however, there has been no systematic study of the changes in gene expression induced by drugs known to cause IDRs. A major impediment to the study of the mechanisms of IDRs is the paucity of valid animal models, and if we had a better mechanistic understanding, it should be easier to develop such models. There is growing evidence that these adverse reactions are more varied and complex than previously recognized, and it is unlikely that a quick fix will be achieved. However, IDRs are an important cause of patient morbidity and mortality and markedly increase the uncertainty of drug development; therefore, continued basic research in this area is essential.
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Affiliation(s)
- Jack Uetrecht
- Leslie Dan Facultyof Pharmacy, University of Toronto, Toronto, Canada.
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34
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Abstract
Clinical characteristics and circumstantial evidence suggest that idiosyncratic drug reactions are caused by reactive metabolites and are immune-mediated; however, there are few definitive data and there are likely exceptions. There are three principal hypotheses for how reactive metabolites might induce an immune-mediated idiosyncratic reaction: the hapten hypothesis, the danger hypothesis, and the PI hypothesis. It has been proposed that some idiosyncratic reactions, especially those involving the liver, represent metabolic idiosyncrasy; however, there are even less data to support this hypothesis. The unpredictable nature of these reactions makes mechanistic studies difficult. There is a very strong association with specific human leukocyte antigen (HLA) genes for certain reactions, but this has only been demonstrated for very few drugs. Animal models represent a very powerful tool for mechanistic studies, but the number of valid models is also limited. There may be biomarkers of risk; however, much more work needs to be done.
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Affiliation(s)
- Jack Uetrecht
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario M5S 2S2, Canada.
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35
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Yamada H, Yamaguchi JI, Iida I, Okuyama S. [Idiosyncratic drug toxicity]. Nihon Yakurigaku Zasshi 2006; 127:473-80. [PMID: 16880698 DOI: 10.1254/fpj.127.473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
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36
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Yang XX, Hu ZP, Chan SY, Zhou SF. Monitoring drug-protein interaction. Clin Chim Acta 2005; 365:9-29. [PMID: 16199025 DOI: 10.1016/j.cca.2005.08.021] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Revised: 08/16/2005] [Accepted: 08/23/2005] [Indexed: 11/25/2022]
Abstract
A variety of therapeutic drugs can undergo biotransformation via Phase I and Phase II enzymes to reactive metabolites that have intrinsic chemical reactivity toward proteins and cause potential organ toxicity. A drug-protein adduct is a protein complex that forms when electrophilic drugs or their reactive metabolite(s) covalently bind to a protein molecule. Formation of such drug-protein adducts eliciting cellular damages and immune responses has been a major hypothesis for the mechanism of toxicity caused by numerous drugs. The monitoring of protein-drug adducts is important in the kinetic and mechanistic studies of drug-protein adducts and establishment of dose-toxicity relationships. The determination of drug-protein adducts can also provide supportive evidence for diagnosis of drug-induced diseases associated with protein-drug adduct formation in patients. The plasma is the most commonly used matrix for monitoring drug-protein adducts due to its convenience and safety. Measurement of circulating antibodies against drug-protein adducts may be used as a useful surrogate marker in the monitoring of drug-protein adducts. The determination of plasma protein adducts and/or relevant antibodies following administration of several drugs including acetaminophen, dapsone, diclofenac and halothane has been conducted in clinical settings for characterizing drug toxicity associated with drug-protein adduct formation. The monitoring of drug-protein adducts often involves multi-step laboratory procedure including sample collection and preliminary preparation, separation to isolate or extract the target compound from a mixture, identification and determination. However, the monitoring of drug-protein adducts is often difficult because of short half-lives of the protein adducts, sampling problem and lack of sensitive analytical techniques for the protein adducts. Currently, chromatographic (e.g. high performance liquid chromatography) and immunological methods (e.g. enzyme-linked immunosorbent assay) are two major techniques used to determine protein adducts of drugs in patients. The present review highlights the importance for clinical monitoring of drug-protein adducts, with an emphasis on methodology and with a further discussion of the application of these techniques to individual drugs and their target proteins.
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Affiliation(s)
- Xiao-Xia Yang
- Department of Pharmacy, Faculty of Science, National University of Singapore, Science Drive 4, Singapore 117543, Singapore
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37
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Bergh MS, Budsberg SC. The Coxib NSAIDs: Potential Clinical and Pharmacologic Importance in Veterinary Medicine. J Vet Intern Med 2005. [DOI: 10.1111/j.1939-1676.2005.tb02741.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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38
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Lim HK, Duczak N, Brougham L, Elliot M, Patel K, Chan K. AUTOMATED SCREENING WITH CONFIRMATION OF MECHANISM-BASED INACTIVATION OF CYP3A4, CYP2C9, CYP2C19, CYP2D6, AND CYP1A2 IN POOLED HUMAN LIVER MICROSOMES. Drug Metab Dispos 2005; 33:1211-9. [PMID: 15860655 DOI: 10.1124/dmd.104.003475] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A strategy is proposed to profile compounds for mechanism-based inactivation of CYP3A4, CYP2C19, CYP2C9, CYP2D6, and CYP1A2 based on an apparent partition ratio screen. Potent positives from the screen are confirmed by time- and concentration-dependent inactivation assays. Quasi-irreversible inhibitions are then differentiated from irreversible inactivations by oxidation with potassium ferricyanide and/or dialysis. The three-step screening procedure has been validated with acceptable accuracy and precision for detection and confirmation of mechanism-based inactivators in drug discovery. We report here the apparent partition ratios for 19 mechanism-based inactivators and four quasi-irreversible inhibitors obtained under the same experimental conditions. The apparent partition ratio screen was automated to provide throughput for determining structure-mechanism-based inactivation relationships. Information about reversibility can be used to assess potential toxicity mediated by covalent adducts, as well as the potential for pharmacokinetic drug-drug interactions. Direct comparison of known mechanism-based inactivators and quasi-irreversible inhibitors, based on our screening of apparent partition ratios, has identified ritonavir, mibefradil, and azamulin as highly effective mechanism-based inactivators; e.g., 1 mol of CYP3A4 was inactivated on turnover of about 2 mol of compound. Other mechanism-based inactivators we identified include bergamottin (CYP1A2 besides previously reported CYP3A4), troglitazone (CYP3A4), rosiglitazone (CYP3A4), and pioglitazone (CYP3A4). Comparison of the apparent partition ratios and inactivation clearance data for the three glitazones suggests that the chromane moiety on troglitazone contributes to its greater potency for mechanism-based inactivation.
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Affiliation(s)
- Heng-Keang Lim
- Johnson & Johnson Pharmaceutical Research Institute, Preclinical Pharmacokinetics, Preclinical Drug Evaluation, OCD, K-007, 1001 Route 202 North, P.O. Box 300, Raritan, NJ 08869, USA.
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39
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Abstract
A comprehensive, multidisciplinary approach is proposed here for the development of a drug with an acceptable safety profile. Key parameters to be considered for drug safety evaluation based on this comprehensive approach include the following: (1) Pharmacology: Possible toxicity due to drug-target interactions, including interactions with unintended molecular targets, or with molecular targets in unintended organs. (2) Chemistry: Chemical scaffolding and side-chains with safety concerns. (3) Toxicology: Toxicity in animals in vivo, and in relevant animal and human cells in culture. (4) Drug metabolism and pharmacokinetics: Safety concerns due to toxification or detoxification, organ distribution, clearance and pharmacokinetic drug-drug interactions. (5) RISK FACTORS: Physiological, environmental and genetic factors that may enhance a patient's susceptibility. It is proposed that this integrated, multidisciplinary approach to safety evaluation may enhance the accuracy of the prediction of drug safety and thereby the efficiency of drug development.
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Affiliation(s)
- Albert P Li
- Advanced Pharmaceutical Sciences, Inc., PMB #146, 6400 Baltimore National Pike, Baltimore, MD 21228, USA.
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40
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Kurian JR, Bajad SU, Miller JL, Chin NA, Trepanier LA. NADH cytochrome b5 reductase and cytochrome b5 catalyze the microsomal reduction of xenobiotic hydroxylamines and amidoximes in humans. J Pharmacol Exp Ther 2004; 311:1171-8. [PMID: 15302896 DOI: 10.1124/jpet.104.072389] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Hydroxylamine metabolites, implicated in dose-dependent and idiosyncratic toxicity from arylamine drugs, and amidoximes, used as pro-drugs, are metabolized by an as yet incompletely characterized NADH-dependent microsomal reductase system. We hypothesized that NADH cytochrome b5 reductase and cytochrome b5 were responsible for this enzymatic activity in humans. Purified human soluble NADH cytochrome b5 reductase and cytochrome b5, expressed in Escherichia coli, efficiently catalyzed the reduction of sulfamethoxazole hydroxylamine, dapsone hydroxylamine, and benzamidoxime, with apparent Km values similar to those found in human liver microsomes and specific activities (Vmax) 74 to 235 times higher than in microsomes. Minimal activity was seen with either protein alone, and microsomal protein did not enhance activity other than additively. All three reduction activities were significantly correlated with immunoreactivity for cytochrome b5 in individual human liver microsomes. In addition, polyclonal antibodies to both NADH cytochrome b5 reductase and cytochrome b5 significantly inhibited reduction activity for sulfamethoxazole hydroxylamine. Finally, fibroblasts from a patient with type II hereditary methemoglobinemia (deficient in NADH cytochrome b5 reductase) showed virtually no activity for hydroxylamine reduction, compared with normal fibroblasts. These results indicate a novel direct role for NADH cytochrome b5 reductase and cytochrome b5 in xenobiotic metabolism and suggest that pharmacogenetic variability in either of these proteins may effect drug reduction capacity.
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Affiliation(s)
- Joseph R Kurian
- Department of Medical Sciences, University of Wisconsin-Madison, School of Veterinary Medicine, 2015 Linden Drive, Madison, WI 53706, USA
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Affiliation(s)
- Albert P Li
- Advanced Pharmaceutical Sciences, PMB#146, 6400 Baltimore National Pike, Baltimore, MD 21228, USA
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Trepanier LA, Yoder AR, Bajad S, Beckwith MD, Bellehumeur JL, Graziano FM. Plasma Ascorbate Deficiency Is Associated With Impaired Reduction of Sulfamethoxazole-Nitroso in HIV Infection. J Acquir Immune Defic Syndr 2004; 36:1041-50. [PMID: 15247557 DOI: 10.1097/00126334-200408150-00007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The objective of these studies was to determine the role of ascorbate deficiency in HIV infection in the defective detoxification of sulfamethoxazole-nitroso, the metabolite thought to mediate sulfonamide hypersensitivity reactions. METHODS Fifty-one HIV-infected patients and 26 healthy volunteers were evaluated. Vitamin supplementation histories were obtained, and blood samples were collected for determination of plasma ascorbate, dehydroascorbate, and cysteine concentrations, erythrocyte glutathione concentrations, and plasma reduction of sulfamethoxazole-nitroso in vitro. RESULTS Plasma ascorbate concentrations were significantly lower in HIV-positive patients not taking vitamin supplements (29.5 +/- 22.3 microM) than in healthy subjects (54.8 +/- 22.3 microM; P = 0.0005) and patients taking 500-1000 mg of ascorbate daily (82.5 +/- 26.3 microM; P < 0.0001). Plasma ascorbate deficiency was strongly correlated with impaired reduction of sulfamethoxazole-nitroso to its hydroxylamine (r = 0.60, P < 0.0001), and during in vitro reduction, the loss of plasma ascorbate was strongly associated with the amount of nitroso reduced (r = 0.70, P < 0.0001). Ascorbate added ex vivo normalized this reduction pathway. Erythrocyte glutathione concentrations were significantly lower in HIV-positive patients (0.98+/-0.32 mM) than in healthy subjects (1.45+/-0.49 mM; P = 0.001), but this finding was unrelated to ascorbate supplementation. There was trend toward lower plasma cysteine concentrations in patients (8.4+/-3.9 microM) than in controls (10.3+/-4.3 microM), but this trend was similarly unrelated to ascorbate supplementation. Dehydroascorbate concentrations were not significantly higher in HIV-positive patients (7.4+/-10.5%) than in healthy controls (4.0+/-6.2%), even in the subset of patients taking ascorbate (8.4+/-9.4%). CONCLUSIONS Ascorbate deficiency is common in HIV-positive patients and is associated with impaired detoxification of sulfamethoxazole-nitroso, the suspected proximate toxin in sulfonamide hypersensitivity. Patients taking daily ascorbate supplements (500-1000 mg) achieved high plasma ascorbate concentrations and did not show this detoxification defect. Ascorbate deficiency (or supplementation) was not associated with changes in glutathione or cysteine concentrations. These data suggest that ascorbate deficiency, independent of thiol status, may be an important determinant of impaired drug detoxification in HIV infection.
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Affiliation(s)
- Lauren A Trepanier
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin--Madison, Madison, WI 53706-1102, USA.
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Abstract
Idiosyncratic toxicity to potentiated sulfonamides occurs in both humans and dogs, with considerable clinical similarities. The syndrome in dogs can consist of fever, arthropathy, blood dyscrasias (neutropenia, thrombocytopenia, or hemolytic anemia), hepatopathy consisting of cholestasis or necrosis, skin eruptions, uveitis, or keratoconjunctivitis sicca. Other manifestations seen less commonly include protein-losing nephropathy, meningitis, pancreatitis, pneumonitis, or facial nerve palsy. The pathogenesis of these reactions is not completely understood, but may be due to a T-cell-mediated response to proteins haptenated by oxidative sulfonamide metabolites. Our laboratory is working on tests to characterize dogs with possible idiosyncratic sulfonamide reactions, to include ELISA for anti-drug antibodies, immunoblotting for antibodies directed against liver proteins, flow cytometry for drug-dependent anti-platelet antibodies, and in vitro cytotoxicity assays. The management of idiosyncratic sulfonamide toxicity involves client education to identify clinical signs early and allow rapid drug discontinuation, supportive care to include possibly ascorbate and glutathione precursors, and avoidance of subsequent re-exposure. It is important to realize that only antimicrobial sulfonamides, such as sulfamethoxazole, sulfadiazine, and sulfadimethoxine, share this clinical syndrome. There is no evidence for cross-reactivity with drugs that have different underlying structures but share a sulfonamide moiety, such as acetazolamide, furosemide, glipizide, or hydrochlorthiazide.
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Affiliation(s)
- L A Trepanier
- Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI 53706, USA.
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Becker K, Tilley L, Vennerstrom JL, Roberts D, Rogerson S, Ginsburg H. Oxidative stress in malaria parasite-infected erythrocytes: host–parasite interactions. Int J Parasitol 2004; 34:163-89. [PMID: 15037104 DOI: 10.1016/j.ijpara.2003.09.011] [Citation(s) in RCA: 420] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2003] [Revised: 09/18/2003] [Accepted: 09/18/2003] [Indexed: 01/09/2023]
Abstract
Experimenta naturae, like the glucose-6-phosphate dehydrogenase deficiency, indicate that malaria parasites are highly susceptible to alterations in the redox equilibrium. This offers a great potential for the development of urgently required novel chemotherapeutic strategies. However, the relationship between the redox status of malarial parasites and that of their host is complex. In this review article we summarise the presently available knowledge on sources and detoxification pathways of reactive oxygen species in malaria parasite-infected red cells, on clinical aspects of redox metabolism and redox-related mechanisms of drug action as well as future prospects for drug development. As delineated below, alterations in redox status contribute to disease manifestation including sequestration, cerebral pathology, anaemia, respiratory distress, and placental malaria. Studying haemoglobinopathies, like thalassemias and sickle cell disease, and other red cell defects that provide protection against malaria allows insights into this fine balance of redox interactions. The host immune response to malaria involves phagocytosis as well as the production of nitric oxide and oxygen radicals that form part of the host defence system and also contribute to the pathology of the disease. Haemoglobin degradation by the malarial parasite produces the redox active by-products, free haem and H(2)O(2), conferring oxidative insult on the host cell. However, the parasite also supplies antioxidant moieties to the host and possesses an efficient enzymatic antioxidant defence system including glutathione- and thioredoxin-dependent proteins. Mechanistic and structural work on these enzymes might provide a basis for targeting the parasite. Indeed, a number of currently used drugs, especially the endoperoxide antimalarials, appear to act by increasing oxidant stress, and novel drugs such as peroxidic compounds and anthroquinones are being developed.
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Affiliation(s)
- Katja Becker
- Interdisciplinary Research Center, Heinrich-Buff-Ring 26-32, Justus-Liebig University, D-35392 Giessen, Germany.
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Coleman MD, Khalaf LF, Nicholls PJ. Aminoglutethimide-induced leucopenia in a mouse model: effects of metabolic and structural determinates. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2003; 15:27-32. [PMID: 21782676 DOI: 10.1016/j.etap.2003.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2003] [Accepted: 08/07/2003] [Indexed: 05/31/2023]
Abstract
A model of human leucopenia has been developed further in the female mouse. Following daily administration to female mice of 50 mg/kg of the aromatase inhibitor aminoglutethimide, significant falls in platelet and white cell counts occurred after 2 and 3 weeks. At week 4, drug dosage was stopped and the cell counts recovered at the end of that week, although on rechallenge at the beginning of week 5, both platelet and white cell counts fell rapidly. Administration to the mice of structural analogues of aminoglutethimide, such as WSP-3, glutethimide and 4-nitroglutethimide, showed no reductions in platelet and white cell counts. The haemotoxicity of aminoglutethimide over 21 days was unaffected by the presence of either the P-450 inhibitor SKF-525A or the hepatic P-450 inducer phenobarbitone. However, the co-administration of cimetidine abolished the haemotoxicity of aminoglutethimide in terms of platelet and white cell levels. In in vitro studies, both aminoglutethimide and WSP-3 were oxidised to cytotoxic species, although aminoglutethimide was significantly more cytotoxic than WSP-3. The NADPH-dependent covalent binding of (14)C aminoglutethimide to mouse microsomes in vitro was significantly reduced by the presence of cimetidine. The activation of the compound to reactive species in vitro, the inhibitory effects of cimetidine in vivo and in vitro, as well as the rapid fall in the in vivo white cell count on rechallenge with aminoglutethimide suggest that this model illustrates a form of leucopenia which may be related to hapten formation and subsequent immune-mediated platelet and white cell lysis.
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Affiliation(s)
- Michael D Coleman
- Mechanisms of Drug Toxicity Group, Pharmaceutical Sciences Institute, Aston University, Aston Triangle, Birmingham B47ET, UK
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Abstract
Toxicity testing has been ineffective in the prediction of drug candidates that will be associated with a relatively high incidence of idiosyncratic drug reactions (IDRs). Circumstantial evidence suggests the involvement of reactive metabolites in the aetiology of these reactions and this has prompted several companies to screen drug candidates for the formation of such compounds. Most drugs form at least one reactive metabolite. To develop efficient prediction methods, a better understanding of the basic mechanisms involved is essential. This review highlights the current mechanistic hypotheses of IDRs and discusses future directions in the development of better predictive tests.
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Affiliation(s)
- Jack Uetrecht
- Faculty of Pharmacy, University of Toronto, 19 Russell St, Toronto, Canada M5S 2S2.
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