1
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Qin L, Huang CH, Liu CQ, Zhao CF, Li PL, Tang TS, Li J, Xie LN, Shao B, Shao J, Mao L, Li R, Zhang L, Zhu BZ. Molecular mechanism for the activation of the potent hepatotoxin acetylhydrazine: Identification of the initial N-centered radical and the secondary C-centered radical intermediates. Free Radic Biol Med 2023; 204:20-27. [PMID: 37094755 DOI: 10.1016/j.freeradbiomed.2023.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 04/06/2023] [Accepted: 04/19/2023] [Indexed: 04/26/2023]
Abstract
Acetylhydrazine (AcHZ), a major human metabolite of the widely-used anti-tuberculosis drug isoniazid (INH), was considered to be responsible for its serious hepatotoxicity and potentially fatal liver injury. It has been proposed that reactive radical species produced from further metabolic activation of AcHZ might be responsible for its hepatotoxicity. However, the exact nature of such radical species remains not clear. Through complementary applications of ESR spin-trapping and HPLC/MS methods, here we show that the initial N-centered radical intermediate can be detected and identified from AcHZ activated by transition metal ions (Mn(III)Acetate and Mn(III) pyrophosphate) and myeloperoxidase. The exact location of the radical was found to be at the distal-nitrogen of the hydrazine group by 15N-isotope-labeling techniques via using 15N-labeled AcHZ we synthesized. Additionally, the secondary C-centered radical was identified unequivocally as the reactive acetyl radical by complementary applications of ESR spin-trapping and persistent radical TEMPO trapping coupled with HPLC/MS analysis. This study represents the first detection and unequivocal identification of the initial N-centered radical and its exact location, as well as the reactive secondary acetyl radical. These findings should provide new perspectives on the molecular mechanism of AcHZ activation, which may have potential biomedical and toxicological significance for future research on the mechanism of INH-induced hepatotoxicity.
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Affiliation(s)
- Li Qin
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, School of Resources and Environment, The University of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing, 100085, PR China; School of Public Health, Zhejiang Chinese Medical University, Hangzhou, 310053, China
| | - Chun-Hua Huang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, School of Resources and Environment, The University of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing, 100085, PR China.
| | - Cui-Qing Liu
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, 310053, China
| | - Chuan-Fang Zhao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, School of Resources and Environment, The University of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing, 100085, PR China
| | - Pei-Lin Li
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, School of Resources and Environment, The University of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing, 100085, PR China
| | - Tian-Shu Tang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, School of Resources and Environment, The University of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing, 100085, PR China
| | - Jun Li
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, School of Resources and Environment, The University of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing, 100085, PR China
| | - Lin-Na Xie
- National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Bo Shao
- School of Public Health, Jining Medical University, Jining, Shandong, 272067, PR China
| | - Jie Shao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, School of Resources and Environment, The University of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing, 100085, PR China
| | - Li Mao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, School of Resources and Environment, The University of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing, 100085, PR China
| | - Ran Li
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, 310053, China
| | - Lu Zhang
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, 310053, China
| | - Ben-Zhan Zhu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, School of Resources and Environment, The University of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing, 100085, PR China; School of Resources and Environment, The University of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Beijing, PR China.
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2
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Qin L, Huang CH, Mao L, Shao B, Zhu BZ. First unequivocal identification of the critical acyl radicals from the anti-tuberculosis drug isoniazid and its hydrazide analogs by complementary applications of ESR spin-trapping and HPLC/MS methods. Free Radic Biol Med 2020; 154:1-8. [PMID: 32360612 DOI: 10.1016/j.freeradbiomed.2020.04.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/17/2020] [Accepted: 04/23/2020] [Indexed: 10/24/2022]
Abstract
The carbon-centered isonicotinic acyl radical of isoniazid (INH), a widely-used frontline anti-tuberculosis drug, has been considered to play a critical role in inhibiting Mycobacterium tuberculosis, but not fully identified. Here we show that this radical intermediate can be unequivocally characterized by complementary applications of ESR spin-trapping and HPLC/MS methods by employing N-tert-butyl-α-phenylnitrone (PBN) as the suitable spin-trapping agent, which can form the most stable radical adduct. More importantly, for the first time, analogous carbon-centered acyl radicals and their respective NAD+ adducts have also been detected and identified from its two isomers (nicotinic acid hydrazide and 2-pyridinecarbohydrazide) and benzhydrazide which are structurally-related to INH, but not by 2-chloroisonicotinohydrazide. This study represents the first unequivocal identification of the carbon-centered acyl radicals of INH and other hydrazide analogs by both ESR spin-trapping and HPLC/MS methods, which may have broad biomedical and toxicological significance for future research for more efficient hydrazide anti-tuberculosis drugs.
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Affiliation(s)
- Li Qin
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Chun-Hua Huang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China.
| | - Li Mao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Bo Shao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; School of Public Health, Jining Medical University, Jining, Shandong, 272067, PR China
| | - Ben-Zhan Zhu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China; Joint Institute for Environmental Science, Research Center for Eco-Environmental Sciences and Hong Kong Baptist University, Beijing/Hong Kong, PR China.
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3
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Qin L, Huang CH, Xu D, Xie LN, Shao J, Mao L, Kalyanaraman B, Zhu BZ. Molecular mechanism for the activation of the anti-tuberculosis drug isoniazid by Mn(III): First detection and unequivocal identification of the critical N-centered isoniazidyl radical and its exact location. Free Radic Biol Med 2019; 143:232-239. [PMID: 31319159 DOI: 10.1016/j.freeradbiomed.2019.07.012] [Citation(s) in RCA: 8] [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: 04/08/2019] [Revised: 07/13/2019] [Accepted: 07/14/2019] [Indexed: 01/24/2023]
Abstract
Isoniazid (INH), the most-widely used anti-tuberculosis drug, has been shown to be activated by Mn(III) to produce the reactive carbon-centered isonicotinic acyl radical, which was considered to be responsible for its anti-tuberculosis activity. However, it is still not clear whether the previously-proposed N-centered isoniazidyl radical intermediate can be initially produced or not; and if so, what is its exact location on the hydrazine group, distal- or proximal-nitrogen? Through complementary applications of ESR spin-trapping and HPLC/MS methods, here we show that the characteristic and transient N-centered isoniazidyl radical intermediate can be detected and identified from INH activation uniquely by Mn(III)Acetate not by Mn(III) pyrophosphate. The exact location of the radical was found to be at the distal-nitrogen of the hydrazine group by 15N-isotope-labeling techniques via using 15N-labeled INH. Diisonicotinyl hydrazine was identified as a new reaction product from INH/Mn(III). Analogous results were observed with other hydrazides. This study represents the first detection and unequivocal identification of the initial N-centered isoniazidyl radical and its exact location. These findings should provide a new perspective on the molecular mechanism of INH activation, which may have broad biomedical and toxicological significance for future research for more efficient hydrazide anti-tuberculosis drugs.
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Affiliation(s)
- Li Qin
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, P. R. China; University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Chun-Hua Huang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, P. R. China; University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Dan Xu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, P. R. China; University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Lin-Na Xie
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, P. R. China; National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, 100021, China
| | - Jie Shao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, P. R. China; University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Li Mao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, P. R. China; University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | | | - Ben-Zhan Zhu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, P. R. China; University of Chinese Academy of Sciences, Beijing, 100049, P. R. China; Linus Pauling Institute, Oregon State University, Corvallis, OR, 97331, USA.
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4
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Babu D, Morgan AG, Reiz B, Whittal RM, Almas S, Lacy P, Siraki AG. Eosinophil peroxidase oxidizes isoniazid to form the active metabolite against M. tuberculosis, isoniazid-NAD . Chem Biol Interact 2019; 305:48-53. [PMID: 30922765 DOI: 10.1016/j.cbi.2019.03.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 03/14/2019] [Accepted: 03/21/2019] [Indexed: 11/24/2022]
Abstract
The formation of isonicotinyl-nicotinamide adenine dinucleotide (INH-NAD+) by the mycobacterial catalase-peroxidase enzyme, KatG, was known to be the major component of the mode of action of isoniazid (INH), an anti-tuberculosis drug. However, there are other enzymes that may catalyze this reaction. We have previously reported that neutrophil myeloperoxidase (MPO) is capable of metabolizing INH through the formation of INH-NAD+ adduct, which could be attributed to being a possible mode of action of INH. However, eosinophilic infiltration of the lungs is more pronounced and characteristic of granulomas in Mycobacterium tuberculosis-infected patients. Thus, the aim of the present study is to investigate the role of eosinophil peroxidase (EPO), a key eosinophil enzyme, during INH metabolism and the formation of its active metabolite, INH-NAD+ using purified EPO and eosinophils isolated from asthmatic donors. UV-Vis spectroscopy revealed INH oxidation by EPO led to a new product (λmax = 326 nm) in the presence of NAD+. This adduct was confirmed to be INH-NAD+ using LC-MS analysis where the intact adduct was detected (m/z = 769). Furthermore, EPO catalyzed the oxidation of INH and formed several free radical intermediates as assessed by electron paramagnetic resonance (EPR) spin-trapping; a carbon-centred radical, which is considered to be the reactive metabolite that binds with NAD+, was found when superoxide dismutase was included in the reaction. Our findings suggest that eosinophilic EPO may also play a role in the pharmacological activity of INH through the formation of INH-NAD+ adduct, and supports further evidence that human cells and enzymes are capable of producing the active metabolite involved in tuberculosis treatment.
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Affiliation(s)
- Dinesh Babu
- Faculty of Pharmacy and Pharmaceutical Sciences, Katz Group Centre for Pharmacy & Health Research, University of Alberta, Edmonton, AB, Canada
| | - Andrew G Morgan
- Faculty of Pharmacy and Pharmaceutical Sciences, Katz Group Centre for Pharmacy & Health Research, University of Alberta, Edmonton, AB, Canada
| | - Béla Reiz
- Department of Chemistry, Faculty of Sciences, University of Alberta, Edmonton, AB, Canada
| | - Randy M Whittal
- Department of Chemistry, Faculty of Sciences, University of Alberta, Edmonton, AB, Canada
| | - Sarah Almas
- Pulmonary Research Group, Department of Medicine, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Paige Lacy
- Pulmonary Research Group, Department of Medicine, Faculty of Medicine & Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Arno G Siraki
- Faculty of Pharmacy and Pharmaceutical Sciences, Katz Group Centre for Pharmacy & Health Research, University of Alberta, Edmonton, AB, Canada.
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5
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Jaladanki CK, Shaikh A, Bharatam PV. Biotransformation of Isoniazid by Cytochromes P450: Analyzing the Molecular Mechanism using Density Functional Theory. Chem Res Toxicol 2017; 30:2060-2073. [DOI: 10.1021/acs.chemrestox.7b00129] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chaitanya K. Jaladanki
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector -67, S. A. S. Nagar, Mohali, 160 062 Punjab, India
| | - Akbar Shaikh
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector -67, S. A. S. Nagar, Mohali, 160 062 Punjab, India
| | - Prasad V. Bharatam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), Sector -67, S. A. S. Nagar, Mohali, 160 062 Punjab, India
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6
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Marchand V, Charlier N, Verrax J, Buc-Calderon P, Levêque P, Gallez B. Use of a cocktail of spin traps for fingerprinting large range of free radicals in biological systems. PLoS One 2017; 12:e0172998. [PMID: 28253308 PMCID: PMC5333873 DOI: 10.1371/journal.pone.0172998] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 02/13/2017] [Indexed: 11/18/2022] Open
Abstract
It is well established that the formation of radical species centered on various atoms is involved in the mechanism leading to the development of several diseases or to the appearance of deleterious effects of toxic molecules. The detection of free radical is possible using Electron Paramagnetic Resonance (EPR) spectroscopy and the spin trapping technique. The classical EPR spin-trapping technique can be considered as a "hypothesis-driven" approach because it requires an a priori assumption regarding the nature of the free radical in order to select the most appropriate spin-trap. We here describe a "data-driven" approach using EPR and a cocktail of spin-traps. The rationale for using this cocktail was that it would cover a wide range of biologically relevant free radicals and have a large range of hydrophilicity and lipophilicity in order to trap free radicals produced in different cellular compartments. As a proof-of-concept, we validated the ability of the system to measure a large variety of free radicals (O-, N-, C-, or S- centered) in well characterized conditions, and we illustrated the ability of the technique to unambiguously detect free radical production in cells exposed to chemicals known to be radical-mediated toxic agents.
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Affiliation(s)
- Valérie Marchand
- Louvain Drug Research Institute, Biomedical Magnetic Resonance Research Group, Université catholique de Louvain, Brussels, Belgium
| | - Nicolas Charlier
- Louvain Drug Research Institute, Biomedical Magnetic Resonance Research Group, Université catholique de Louvain, Brussels, Belgium
| | - Julien Verrax
- Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group, Université catholique de Louvain, Brussels, Belgium
| | - Pedro Buc-Calderon
- Louvain Drug Research Institute, Toxicology and Cancer Biology Research Group, Université catholique de Louvain, Brussels, Belgium
- Facultad de Ciencias de la Salud, Universidad Arturo Prat, Iquique, Chile
| | - Philippe Levêque
- Louvain Drug Research Institute, Biomedical Magnetic Resonance Research Group, Université catholique de Louvain, Brussels, Belgium
| | - Bernard Gallez
- Louvain Drug Research Institute, Biomedical Magnetic Resonance Research Group, Université catholique de Louvain, Brussels, Belgium
- * E-mail:
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7
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Melton D, Lewis CD, Price NE, Gates KS. Covalent adduct formation between the antihypertensive drug hydralazine and abasic sites in double- and single-stranded DNA. Chem Res Toxicol 2014; 27:2113-8. [PMID: 25405892 PMCID: PMC4269403 DOI: 10.1021/tx5003657] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
![]()
Hydralazine
(4) is an antihypertensive agent that
displays both mutagenic and epigenetic properties. Here, gel electrophoretic,
mass spectroscopic, and chemical kinetics methods were used to provide
evidence that medicinally relevant concentrations of 4 rapidly form covalent adducts with abasic sites in double- and single-stranded
DNA under physiological conditions. These findings raise the intriguing
possibility that the genotoxic properties of this clinically used
drug arise via reactions with an endogenous DNA lesion rather than
with the canonical structure of DNA.
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Affiliation(s)
- Douglas Melton
- Department of Chemistry, ‡Department of Biochemistry, University of Missouri , 125 Chemistry Building, Columbia, Missouri 65211, United States
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8
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Elucidating the structural basis of diphenyl ether derivatives as highly potent enoyl-ACP reductase inhibitors through molecular dynamics simulations and 3D-QSAR study. J Mol Model 2014; 20:2319. [PMID: 24935113 DOI: 10.1007/s00894-014-2319-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 05/26/2014] [Indexed: 10/25/2022]
Abstract
Diphenyl ether derivatives are good candidates for anti-tuberculosis agents that display a promising potency for inhibition of InhA, an essential enoyl-acyl carrier protein (ACP) reductase involved in fatty acid biosynthesis pathways in Mycobacterium tuberculosis. In this work, key structural features for the inhibition were identified by 3D-QSAR CoMSIA models, constructed based on available experimental binding properties of diphenyl ether inhibitors, and a set of four representative compounds was subjected to MD simulations of inhibitor-InhA complexes for the calculation of binding free energies. The results show that bulky groups are required for the R1 substituent on the phenyl A ring of the inhibitors to favor a hydrophobic pocket formed by residues Phe149, Met155, Pro156, Ala157, Tyr158, Pro193, Met199, Val203, Leu207, Ile215, and Leu218. Small substituents with a hydrophilic property are required at the R3 and R4 positions of the inhibitor phenyl B rings to form hydrogen bonds with the backbones of Gly96 and Met98, respectively. For the R2 substituent, small substituents with simultaneous hydrophilic or hydrophobic properties are required to favor the interaction with the pyrophosphate moiety of NAD(+) and the methyl side chain of Ala198, respectively. The reported data provide structural guidance for the design of new and potent diphenyl ether-based inhibitors with high inhibitory activities against M. tuberculosis InhA.
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9
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Kamsri P, Koohatammakun N, Srisupan A, Meewong P, Punkvang A, Saparpakorn P, Hannongbua S, Wolschann P, Prueksaaroon S, Leartsakulpanich U, Pungpo P. Rational design of InhA inhibitors in the class of diphenyl ether derivatives as potential anti-tubercular agents using molecular dynamics simulations. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2014; 25:473-488. [PMID: 24785640 DOI: 10.1080/1062936x.2014.898690] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A series of diphenyl ether derivatives were developed and showed promising potency for inhibiting InhA, an essential enoyl acyl carrier protein reductase involved in mycolic acid biosynthesis, leading to the lysis of Mycobacterium tuberculosis. To understand the structural basis of diphenyl ether derivatives for designing more potent inhibitors, molecular dynamics (MD) simulations were performed. Based on the obtained results, the dynamic behaviour in terms of flexibility, binding free energy, binding energy decomposition, conformation, and the inhibitor-enzyme interaction of diphenyl ether inhibitors were elucidated. Phe149, Tyr158, Met161, Met199, Val203 and NAD+ are the key residues for binding of diphenyl ether inhibitors in the InhA binding pocket. Our results could provide the structural concept to design new diphenyl ether inhibitors with better enzyme inhibitory activity against M. tuberculosis InhA. The present work facilitates the design of new and potentially more effective anti-tuberculosis agents.
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Affiliation(s)
- P Kamsri
- a Department of Chemistry, Faculty of Science , Ubon Ratchathani University , Ubonratchathani , Thailand
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10
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Sinha BK, Leinisch F, Bhattacharjee S, Mason RP. DNA cleavage and detection of DNA radicals formed from hydralazine and copper (II) by ESR and immuno-spin trapping. Chem Res Toxicol 2014; 27:674-82. [PMID: 24502259 DOI: 10.1021/tx500011m] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Metal ion-catalyzed oxidation of hydrazine and its derivatives leads to the formation of the hydrazyl radical and subsequently to oxy-radicals in the presence of molecular oxygen. Here, we have examined the role of Cu(2+)-catalyzed oxidation of hydralazine in the induction of DNA damage. Neither 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) nor dimethyl sulfoxide (DMSO) was effective in inhibiting hydralazine-Cu(2+)-induced DNA damage. Singlet oxygen did not appear to participate in this DNA cleavage. The one-electron oxidation of hydralazine also leads to the formation of DNA radicals as confirmed by immuno-spin trapping with 5,5-dimethyl-1-pyrroline-N-oxide. Electron spin resonance (ESR) and spin-trapping studies further confirmed the formation of DNA radicals; predominantly, 2'-deoxyadenosine radical adducts were detected, while some radicals were also detected with other nucleosides. Our results suggest that free hydroxyl radicals may not be the main damaging species causing DNA cleavage and that possibly Cu-peroxide complexes, formed from Cu(+)-H2O2, are responsible for this hydralazine-Cu(2+)-induced DNA cleavage.
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Affiliation(s)
- Birandra K Sinha
- Laboratory of Toxicology and Pharmacology, National Institutes of Environmental Health Sciences , Research Triangle Park, North Carolina, United States
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11
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Isoniazid: Radical-induced oxidation and reduction chemistry. Bioorg Med Chem Lett 2013; 23:3096-100. [DOI: 10.1016/j.bmcl.2013.03.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 02/27/2013] [Accepted: 03/04/2013] [Indexed: 11/19/2022]
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12
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Arvadia P, Narwaley M, Whittal RM, Siraki AG. 4-Aminobenzoic acid hydrazide inhibition of microperoxidase-11: catalytic inhibition by reactive metabolites. Arch Biochem Biophys 2011; 515:120-6. [PMID: 21840294 DOI: 10.1016/j.abb.2011.07.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 07/27/2011] [Accepted: 07/29/2011] [Indexed: 11/30/2022]
Abstract
Inhibition of human peroxidase enzymes such as myeloperoxidase or eosinophil peroxidase represents a novel therapeutic area, for which there are no current clinical therapeutics. We utilized 4-aminobenzoic acid hydrazide which was reported to be a potent irreversible inhibitor of myeloperoxidase to gain insight into the role of reactive metabolites in catalytic inhibition. In order to carry out detailed studies, we used a model peroxidase, microperoxidase-11 (MP-11). We investigated the heme spectrum of MP-11 in the presence of 4-ABAH and found that heme bleaching occurred that was irreversible. This coincided with an absence of catalytic activity. The spin trap 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) was able to significantly prevent inactivation of peroxidase activity, therefore, we performed ESR spin trapping studies and detected a carbonyl carbon-centered radical of 4-ABAH. In order to determine if the free radical metabolites became bound to MP-11, we performed high-resolution MALDI with elemental analysis to determine the change in elemental composition that occurred in these reactions. These masses were assigned to free radical metabolites of 4-ABAH and were not observed in reactions containing DMPO. We conclude that the 4-ABAH free radical metabolites which were bound to MP-11 were involved in the catalytic inhibition and were scavenged by DMPO.
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Affiliation(s)
- Pratik Arvadia
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada
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13
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Grotzky A, Manaka Y, Kojima T, Walde P. Preparation of catalytically active, covalent α-polylysine-enzyme conjugates via UV/vis-quantifiable bis-aryl hydrazone bond formation. Biomacromolecules 2010; 12:134-44. [PMID: 21171644 DOI: 10.1021/bm101074s] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Covalent UV/vis-quantifiable bis-aryl hydrazone bond formation was investigated for the preparation of conjugates between α-poly-d-lysine (PDL) and either α-chymotrypsin (α-CT) or horseradish peroxidase (HRP). PDL and the enzymes were first modified via free amino groups with the linking reagents succinimidyl 6-hydrazinonicotinate acetone hydrazone (S-HyNic, at pH 7.6) and succinimidyl 4-formylbenzoate (S-4FB, at pH 7.2), respectively. The modified PDL and enzymes were then conjugated at pH 4.7, whereby polymer chains carrying several enzymes were obtained. Kinetics of the bis-aryl hydrazone bond formation was investigated spectrophotometrically at 354 nm. Retention of the enzymatic activity after conjugate formation was confirmed by using the substrates N-succinimidyl-l-Ala-l-Ala-l-Pro-l-Phe-p-nitroanilide (for α-CT) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS, for HRP). Thus, not only a mild and efficient preparation and convenient quantification of a conjugate between the polycationic α-polylysine and enzymes could be shown, but also the complete preservation of the enzymatic activity.
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Affiliation(s)
- Andrea Grotzky
- Department of Materials, ETH Zürich, Wolfgang-Pauli-Strasse 10, CH-8093 Zürich, Switzerland
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14
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Investigating the structural basis of arylamides to improve potency against M. tuberculosis strain through molecular dynamics simulations. Eur J Med Chem 2010; 45:5585-93. [DOI: 10.1016/j.ejmech.2010.09.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2010] [Revised: 08/13/2010] [Accepted: 09/04/2010] [Indexed: 11/18/2022]
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15
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Insight into crucial inhibitor–enzyme interaction of arylamides as novel direct inhibitors of the enoyl ACP reductase (InhA) from Mycobacterium tuberculosis: computer-aided molecular design. MONATSHEFTE FUR CHEMIE 2010. [DOI: 10.1007/s00706-010-0359-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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16
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Development of antitubercular compounds based on a 4-quinolylhydrazone scaffold. Further structure–activity relationship studies. Bioorg Med Chem 2009; 17:6063-72. [DOI: 10.1016/j.bmc.2009.06.051] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 06/15/2009] [Accepted: 06/18/2009] [Indexed: 11/18/2022]
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17
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Suarez J, Ranguelova K, Schelvis JPM, Magliozzo RS. Antibiotic resistance in Mycobacterium tuberculosis: peroxidase intermediate bypass causes poor isoniazid activation by the S315G mutant of M. tuberculosis catalase-peroxidase (KatG). J Biol Chem 2009; 284:16146-16155. [PMID: 19363028 DOI: 10.1074/jbc.m109.005546] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
KatG (catalase-peroxidase) in Mycobacterium tuberculosis is responsible for activation of isoniazid (INH), a pro-drug used to treat tuberculosis infections. Resistance to INH is a global health problem most often associated with mutations in the katG gene. The origin of INH resistance caused by the KatG[S315G] mutant enzyme is examined here. Overexpressed KatG[S315G] was characterized by optical, EPR, and resonance Raman spectroscopy and by studies of the INH activation mechanism in vitro. Catalase activity and peroxidase activity with artificial substrates were moderately reduced (50 and 35%, respectively), whereas the rates of formation of oxyferryl heme:porphyrin pi-cation radical and the decay of heme intermediates were approximately 2-fold faster in KatG[S315G] compared with WT enzyme. The INH binding affinity for the resting enzyme was unchanged, whereas INH activation, measured by the rate of formation of an acyl-nicotinamide adenine dinucleotide adduct considered to be a bactericidal molecule, was reduced by 30% compared with WT KatG. INH resistance is suggested to arise from a redirection of catalytic intermediates into nonproductive reactions that interfere with oxidation of INH. In the resting mutant enzyme, a rapid evolution of 5-c heme to 6-c species occurred in contrast with the behavior of WT KatG and KatG[S315T] and consistent with greater flexibility at the heme edge in the absence of the hydroxyl of residue 315. Insights into the effects of mutations at residue 315 on enzyme structure, peroxidation kinetics, and specific interactions with INH are presented.
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Affiliation(s)
- Javier Suarez
- From the Department of Chemistry, Brooklyn College of the City University of New York, Brooklyn, New York 11210; Department of Biochemistry, The Graduate Center of the City University of New York, New York, New York 11216
| | - Kalina Ranguelova
- From the Department of Chemistry, Brooklyn College of the City University of New York, Brooklyn, New York 11210; Department of Biochemistry, The Graduate Center of the City University of New York, New York, New York 11216
| | | | - Richard S Magliozzo
- From the Department of Chemistry, Brooklyn College of the City University of New York, Brooklyn, New York 11210; Department of Biochemistry, The Graduate Center of the City University of New York, New York, New York 11216.
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18
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Ranguelova K, Suarez J, Magliozzo RS, Mason RP. Spin trapping investigation of peroxide- and isoniazid-induced radicals in Mycobacterium tuberculosis catalase-peroxidase. Biochemistry 2008; 47:11377-85. [PMID: 18831539 DOI: 10.1021/bi800952b] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new approach, the immuno-spin trapping assay, used a novel rabbit polyclonal anti-DMPO (5,5-dimethyl-1-pyrroline N-oxide) antiserum to detect protein radical-derived DMPO nitrone adducts in the hemoprotein Mycobacterium tuberculosis catalase-peroxidase (KatG). This work demonstrates that the formation of protein nitrone adducts is dependent on the concentrations of tert-BuOOH and DMPO as shown by Western blotting and an enzyme-linked immunosorbent assay (ELISA). We have also detected protein-protein cross-links formed during turnover of Mtb KatG driven by tert-butyl peroxide ( tert-BuOOH) or enzymatic generation of hydrogen peroxide. DMPO inhibits this dimerization due to its ability to trap the amino acid radicals responsible for the cross-linkage. Chemical modifications by tyrosine and tryptophan blockage suggest that tyrosine residues are one site of formation of the dimers. The presence of the tuberculosis drug isoniazid (INH) also prevented cross-linking as a result of its competition for the protein radical. Protein-DMPO nitrone adducts were also generated by a continuous flux of hydrogen peroxide. These findings demonstrated that the protein-based radicals were formed not only during Mtb KatG turnover with alkyl peroxides but also in the presence of hydrogen peroxide. Furthermore, the formation of protein-DMPO nitrone adducts was accelerated in the presence of isoniazid.
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Affiliation(s)
- Kalina Ranguelova
- Laboratory of Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, P.O. Box 12233, MD F0-01, 111 T. W. Alexander Drive, Research Triangle Park, North Carolina 27709, USA.
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19
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Identification of radical species derived from allergenic 15-hydroperoxyabietic acid and insights into the behaviour of cyclic tertiary allylic hydroperoxides in Fe(II)/Fe(III) systems. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.04.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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20
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Siraki AG, Deterding LJ, Bonini MG, Jiang J, Ehrenshaft M, Tomer KB, Mason RP. Procainamide, but not N-acetylprocainamide, induces protein free radical formation on myeloperoxidase: a potential mechanism of agranulocytosis. Chem Res Toxicol 2008; 21:1143-53. [PMID: 18489081 DOI: 10.1021/tx700415b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Procainamide (PA) is a drug that is used to treat tachycardia in postoperative patients or for long-term maintenance of cardiac arrythmias. Unfortunately, its use has also been associated with agranulocytosis. Here, we have investigated the metabolism of PA by myeloperoxidase (MPO) and the formation of an MPO protein free radical. We hypothesized that PA oxidation by MPO/H 2O 2 would produce a PA cation radical that, in the absence of a biochemical reductant, would lead to the free radical oxidation of MPO. We utilized a novel anti-DMPO antibody to detect DMPO (5,5-dimethyl-1-pyrroline N-oxide) covalently bound to protein, which forms by the reaction of DMPO with a protein free radical. We found that PA metabolism by MPO/H 2O 2 induced the formation of DMPO-MPO, which was inhibited by MPO inhibitors and ascorbate. N-acetyl-PA did not cause DMPO-MPO formation, indicating that the unsubstituted aromatic amine was more oxidizable. PA had a lower calculated ionization potential than N-acetyl-PA. The DMPO adducts of MPO metabolism, as analyzed by electron spin resonance spectroscopy, included a nitrogen-centered radical and a phenyl radical derived from PA, either of which may be involved in the free radical formation on MPO. Furthermore, we also found protein-DMPO adducts in MPO-containing, intact human promyelocytic leukemia cells (HL-60). MPO was affinity-purified from HL-60 cells treated with PA/H 2O 2 and was found to contain DMPO using the anti-DMPO antibody. Mass spectrometry analysis confirmed the identity of the protein as human MPO. These findings were also supported by the detection of protein free radicals with electron spin resonance in the cellular cytosolic lysate. The formation of an MPO protein free radical is believed to be mediated by free radical metabolites of PA, which we characterized by spin trapping. We propose that drug-induced free radical formation on MPO may play a role in the origin of agranulocytosis.
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Affiliation(s)
- Arno G Siraki
- Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, National Institutes of Health, 111 Alexander Dr., Research Triangle Park, NC 27709, USA.
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21
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Tafazoli S, O’Brien PJ. Accelerated Cytotoxic Mechanism Screening of Hydralazine Using an in Vitro Hepatocyte Inflammatory Cell Peroxidase Model. Chem Res Toxicol 2008; 21:904-10. [DOI: 10.1021/tx700371x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shahrzad Tafazoli
- Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada M5S 3M2
| | - Peter J. O’Brien
- Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada M5S 3M2
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22
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Delaine T, Bernardes-Génisson V, Meunier B, Bernadou J. Synthesis of the isonicotinoylnicotinamide scaffolds of the naturally occurring isoniazid-NAD(P) adducts. J Org Chem 2007; 72:675-8. [PMID: 17221997 DOI: 10.1021/jo062100e] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The first syntheses of the 1-hydroxy-1-(pyridin-4-yl)-1,2-dihydro-3H-pyrrolo[3,4-c]pyridin-3-one heterocycle and the 3-aminocarbonyl-4-isonicotinoyl-1,4-dihydropyridine framework present in the isoniazid-NAD(P) adducts are described.
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Affiliation(s)
- Tamara Delaine
- Laboratoire de Chimie de Coordination du CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
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23
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Abstract
For decades after its introduction, the mechanisms of action of the front-line antituberculosis therapeutic agent isoniazid (INH) remained unclear. Recent developments have shown that peroxidative activation of isoniazid by the mycobacterial enzyme KatG generates reactive species that form adducts with NAD(+) and NADP(+) that are potent inhibitors of lipid and nucleic acid biosynthetic enzymes. A direct role for some isoniazid-derived reactive species, such as nitric oxide, in inhibiting mycobacterial metabolic enzymes has also been shown. The concerted effects of these activities - inhibition of cell wall lipid synthesis, depletion of nucleic acid pools and metabolic depression - drive the exquisite potency and selectivity of this agent. To understand INH action and resistance fully, a synthesis of knowledge is required from multiple separate lines of research - including molecular genetic approaches, in vitro biochemical studies and free radical chemistry - which is the intent of this review.
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Affiliation(s)
- Graham S Timmins
- College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
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24
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Broussy S, Bernardes-Génisson V, Quémard A, Meunier B, Bernadou J. The first chemical synthesis of the core structure of the benzoylhydrazine-NAD adduct, a competitive inhibitor of the Mycobacterium tuberculosis enoyl reductase. J Org Chem 2006; 70:10502-10. [PMID: 16323864 DOI: 10.1021/jo051901z] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] An isoniazid-NAD adduct has been recently proposed as the ultimate metabolite responsible for the antituberculous activity of isoniazid (INH). Its structure results from binding of the isonicotinoyl radical at C4 position of the nicotinamide ring of NAD with further possible and debated cyclization to form a cyclic hemiamidal derivative. Replacing the pyridine cycle of INH in INH-NAD adduct by a phenyl cycle (BH-NAD adduct) was shown previously to still retain the activity. On these bases, the core structure (4-benzoyl-1,4-dihydronicotinamide ribonucleoside) of the BH-NAD adduct and a series of analogues have been synthesized by using 3,4-pyridinedicarboximide as starting material. Depending on the nature of the substituent (pyridine or aryl) and on the oxidized or the reduced state of the nicotinamide nucleus, they were found either in a cyclized hemiamidal or an opened form or were shown to exist in equilibrium under cyclized or opened forms. Although none of these compounds could significantly inhibit activity of the InhA or MabA reductases (two possible targets of isoniazid), they represent attractive targets to develop potential second-generation inhibitors, including the total chemical synthesis of the bioactive BH-NAD adduct.
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Affiliation(s)
- Sylvain Broussy
- Laboratoire de Chimie de Coordination du CNRS, 205 route de Narbonne, 31077 Toulouse Cedex 4, France
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25
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Zhao X, Yu H, Yu S, Wang F, Sacchettini JC, Magliozzo RS. Hydrogen peroxide-mediated isoniazid activation catalyzed by Mycobacterium tuberculosis catalase-peroxidase (KatG) and its S315T mutant. Biochemistry 2006; 45:4131-40. [PMID: 16566587 DOI: 10.1021/bi051967o] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Inhibition of the enzyme Mycobacterium tuberculosis InhA (enoyl-acyl carrier protein reductase) due to formation of an isonicotinoyl-NAD adduct (IN-NAD) from isoniazid (INH) and nicotinamide adenine dinucleotide cofactor is considered central to the mode of action of INH, a first-line treatment for tuberculosis infection. INH action against mycobacteria requires catalase-peroxidase (KatG) function, and IN-NAD adduct formation is catalyzed in vitro by M. tuberculosis KatG under a variety of conditions, yet a physiologically relevant approach to the process has not emerged that allows scrutiny of the mechanism and the origins of INH resistance in the most prevalent drug-resistant strain bearing KatG[S315T]. In this report, we describe how hydrogen peroxide, delivered at very low concentrations to ferric KatG, leads to efficient inhibition of InhA due to formation of the IN-NAD adduct. The rate of adduct formation mediated by wild-type KatG was about 20-fold greater than by the isoniazid-resistant KatG[S315T] mutant under optimal conditions (H2O2 supplied along with NAD+ and INH). Slow adduct formation also occurs starting with NADH and INH, in the presence of KatG even in the absence of added peroxide, due to endogenous peroxide. The poor efficiency of the KatG[S315T] mutant can be enhanced merely by increasing the concentration of INH, consistent with this enzyme's reduced affinity for INH binding to the resting enzyme and the catalytically competent enzyme intermediate (Compound I). Origins of drug resistance in the KatG[S315T] mutant enzyme are analyzed at the structural level through examination of the three-dimensional X-ray crystal structure of the mutant enzyme.
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Affiliation(s)
- Xiangbo Zhao
- Department of Chemistry, Brooklyn College, Brooklyn, New York 11210, USA
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26
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Rota C, Liverani L, Spelta F, Mascellani G, Tomasi A, Iannone A, Vismara E. Free radical generation during chemical depolymerization of heparin. Anal Biochem 2006; 344:193-203. [PMID: 16098471 DOI: 10.1016/j.ab.2005.06.043] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2005] [Revised: 06/15/2005] [Accepted: 06/27/2005] [Indexed: 11/16/2022]
Abstract
Low-molecular weight heparins (LMWHs), as compared with unfractionated heparin (UFH), present superior bioavailability, much longer plasma half-life, and lower incidence of side effects. For these reasons, over the past two decades LMWHs have become the drugs of choice for the treatment of deep venous thrombosis, pulmonary embolism, arterial thrombosis, and unstable angina. Furthermore, their use in acute ischemic stroke is currently under study. LMWHs are obtained by UFH depolymerization, which can be performed using various methods, including nitrous acid depolymerization, cleavage by beta-elimination of benzyl ester, enzymatic depolymerization, and peroxyl radical-dependent depolymerization. This article addresses the chemical depolymerization, obtained by free radical attack (mainly hydroxyl radical), of heparin. The electron spin resonance (ESR) spectroscopy, coupled to the spin trapping technique, was employed to study this reaction. Free radical-mediated heparin depolymerization was performed under different chemical conditions. The final products of the reactions were purified and classified on the basis of their molecular weight and other characteristics. The level of heparin fragmentation was different depending on the type of depolymerization reaction used. Moreover, the level of reproducibility and the resulting radical species were different for every type of reaction performed.
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Affiliation(s)
- Cristina Rota
- Department of Biomedical Sciences, University of Modena and Reggio Emilia, Modena 41100, Italy
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27
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Broussy S, Bernardes-Génisson V, Coppel Y, Quémard A, Bernadou J, Meunier B. 1H and 13C NMR characterization of pyridinium-type isoniazid-NAD adducts as possible inhibitors of InhA reductase of Mycobacterium tuberculosis. Org Biomol Chem 2005; 3:670-3. [PMID: 15703806 DOI: 10.1039/b417698g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Oxidative activation of the antituberculous drug isoniazid (INH) in the presence of the NADH cofactor gives a pool of INH-NAD adducts proposed to be involved in the mechanism of action of this drug through inhibition of the reductase InhA. Among these adducts and besides dihydropyridine derivatives, two pyridinium-type isoniazid-NAD adducts were shown to be formed in solution and have been fully characterized by 1H/13C NMR and MS. One of them results from the oxidation of dihydropyridine-type INH-NAD adducts. The spectral data strongly support its existence under two epimeric structures. These epimers arise from a cyclization process between the carboxamide group and the ketone function with the creation of a new chiral center at C-7. The second pyridinium-type adduct was formed in acidic solution by dehydration of the cyclized dihydropyridine-type INH-NAD adducts and also exists as a cyclized structure. Both of these pyridinium-type compounds were inactive as inhibitors of InhA activity and can be considered as deactivated species.
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Affiliation(s)
- Sylvain Broussy
- Laboratoire de Chimie de Coordination du CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
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28
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Sipe HJ, Jaszewski AR, Mason RP. Fast-Flow EPR Spectroscopic Observation of the Isoniazid, Iproniazid, and Phenylhydrazine Hydrazyl Radicals. Chem Res Toxicol 2004; 17:226-33. [PMID: 14967010 DOI: 10.1021/tx0341759] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Hydrazyl radical intermediates have been suggested as important intermediates in the biochemistry of hydrazides and hydrazines. Although spin-trapping studies have intercepted those species previously, there has been no report of the direct observation of the unstable hydrazyl radicals of isoniazid and iproniazid. We have employed the fast-flow technique in electron paramagnetic resonance (EPR) spectroscopy to measure spectra for the short-lived hydrazyl radicals of a family of hydrazides, including the pharmacologically important compounds isoniazid and iproniazid, as well as for a series of phenylhydrazines. Our investigations of the phenylhydrazine radical and the related chloro-substituted analogues have allowed definitive assignments of the hyperfine coupling constants of that toxicologically important free radical. Theoretical values of hyperfine coupling constants, calculated by density functional formalism, provided a guide to assignments for the hydrazyl species and confirmed the experimentally based assignments for phenylhydrazyl radical.
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Affiliation(s)
- Herbert J Sipe
- Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, National Institutes of Health, P.O. Box 12233, Research Triangle Park, North Carolina 27709, USA
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29
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Chouchane S, Girotto S, Yu S, Magliozzo RS. Identification and characterization of tyrosyl radical formation in Mycobacterium tuberculosis catalase-peroxidase (KatG). J Biol Chem 2002; 277:42633-8. [PMID: 12205099 DOI: 10.1074/jbc.m207916200] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The catalytic function of Mycobacterium tuberculosis catalase-peroxidase (KatG) and its role in activation of the anti-tuberculosis antibiotic isoniazid were investigated using rapid freeze-quench electron paramagnetic resonance (RFQ-EPR) experiments. The reaction of KatG with peroxyacetic acid was followed as a function of time using x-band EPR at 77 K. A doublet EPR signal appears within 6.4 ms after mixing and at time points through hundreds of milliseconds. Thereafter, a singlet signal develops and finally predominates after 1 s, with a total yield of radical approximately 0.5 spin/heme. Simulation of the spectra provided EPR parameters consistent with those for tyrosyl radicals. Changes in the hyperfine splitting and/or line width in spectra for l-3,3-[2H2]tyrosine-labeled, but not l-2,4,5,6,7-[2H5]tryptophan-labeled KatG confirmed this assignment. The initial rate of radical formation was unchanged using a 3-fold or 10-fold excess of peroxyacetic acid, consistent with a rate-determining step involving an intermediate. Although Compound I is likely to be the precursor of tyrosyl radical in KatG, neither its EPR signal nor its reduction to Compound II during formation of the radical(s) could be observed. The tyrosyl radical doublet signal was rapidly quenched by addition of isoniazid and benzoic hydrazide, but not by iproniazid, which binds poorly to KatG.
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Affiliation(s)
- Salem Chouchane
- Department of Chemistry, Brooklyn College and the Graduate Center of the City University of New York, Brooklyn, New York 11210, USA
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30
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Nguyen M, Quémard A, Broussy S, Bernadou J, Meunier B. Mn(III) pyrophosphate as an efficient tool for studying the mode of action of isoniazid on the InhA protein of Mycobacterium tuberculosis. Antimicrob Agents Chemother 2002; 46:2137-44. [PMID: 12069966 PMCID: PMC127317 DOI: 10.1128/aac.46.7.2137-2144.2002] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The antituberculosis drug isoniazid (INH) is quickly oxidized by stoichiometric amounts of manganese(III) pyrophosphate. In the presence of nicotinamide coenzymes (NAD+, NADH, nicotinamide mononucleotide [NMN+]) and nicotinic acid adenine dinucleotide (DNAD+), INH oxidation produced the formation of INH-coenzyme adducts in addition to known biologically inactive products (isonicotinic acid, isonicotinamide, and isonicotinaldehyde). A pool of INH-NAD(H) adducts preformed in solution allowed the rapid and strong inhibition of in vitro activity of the enoyl-acyl carrier protein reductase InhA, an INH target in the biosynthetic pathway of mycolic acids: the inhibition was 90 or 60% when the adducts were formed in the presence of NAD+ or NADH, respectively. Under similar conditions, no inhibitory activity of INH-NMN(H) and INH-DNAD(H) adducts was detected. When an isolated pool of 100 nM INH-NAD(H) adducts was first incubated with InhA, the enzyme activity was inhibited by 80%; when present in excess, both NADH and decenoyl-coenzyme A are able to prevent this phenomenon. InhA inhibition by several types of INH-coenzyme adducts coexisting in solution is discussed in relation with the structure of the coenzyme, the stereochemistry of the adducts, and their existence as both open and cyclic forms. Thus, manganese(III) pyrophosphate appears to be an efficient and convenient alternative oxidant to mimic the activity of the Mycobacterium tuberculosis KatG catalase-peroxidase and will be useful for further mechanistic studies of INH activation and for structural investigations of reactive INH species in order to promote the design of new inhibitors of InhA as potential antituberculous drugs.
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Affiliation(s)
- Michel Nguyen
- Laboratoire de Chimie de Coordination du CNRS, 31077 Toulouse Cedex, France
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31
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Nguyen M, Claparols C, Bernadou J, Meunier B. A fast and efficient metal-mediated oxidation of isoniazid and identification of isoniazid-NAD(H) adducts. Chembiochem 2001; 2:877-83. [PMID: 11948876 DOI: 10.1002/1439-7633(20011203)2:12<877::aid-cbic877>3.0.co;2-v] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
It is currently believed that isoniazid (INH) is oxidised inside Mycobacterium tuberculosis to generate, by covalent attachment to the nicotinamide ring of NAD(H) (beta-nicotinamide adenine dinucleotide), a strong inhibitor of InhA, an enzyme essential for mycolic acid biosynthesis. This work was carried out to characterise the InhA inhibitors (named INH-NAD(H) adducts) which are generated, in the presence of the nicotinamide coenzyme NAD+, by oxidation of INH with manganese(III) pyrophosphate, a nonenzymatic and efficient oxidant used to mimic INH activation by the catalase-peroxidase KatG inside M. tuberculosis. The oxidation process is almost complete in less than 15 minutes (in comparison to the slow activation obtained in the KatG-dependent process (2.5 hours) or in the nonenzymatic O2/Mn(II)-dependent activation (5 hours)). The alkylation of NAD+ by the postulated isonicotinoyl radical generates, in solution, a family of INH-NAD(H) adducts. Analyses with liquid chromatography/electrospray ionisation mass spectrometry (LC/ESI-MS) and experiments performed with 18O- and 2H-labelled substrates allowed us to propose two open and four hemiamidal cyclised dihydropyridine structures as the main forms present in solution; these result from the combination of the isonicotinoyl radical and the nicotinamide part of NAD+. A small amount of a secondary oxidation product was also detected. Structural data on the forms present in solution should help in the design of inhibitors of enzymes involved in the biosynthesis of mycolic acids to act as potential antituberculosis drugs.
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Affiliation(s)
- M Nguyen
- Laboratoire de Chimie de Coordination du CNRS, 205 route de Narbonne, 31077 Toulouse cedex 4, France
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32
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Wengenack NL, Rusnak F. Evidence for isoniazid-dependent free radical generation catalyzed by Mycobacterium tuberculosis KatG and the isoniazid-resistant mutant KatG(S315T). Biochemistry 2001; 40:8990-6. [PMID: 11467961 DOI: 10.1021/bi002614m] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The antitubercular agent isoniazid can be activated by Mycobacterium tuberculosis KatG using either a peroxidase compound I/II or a superoxide-dependent oxyferrous pathway. The identity of activated isoniazid is unknown, but it has been suggested that it may be a free radical intermediate. In this work, EPR spin trapping experiments detected isoniazid-derived radicals generated during KatG-mediated oxidation via the peroxidase compound I/II pathway. On the basis of hyperfine splitting patterns and oxygen dependence, these radicals were identified as the acyl, acyl peroxo, and pyridyl radicals of isoniazid. Isoniazid-resistant KatG(S315T) produced the same radicals found with KatG, while the less potent antitubercular agent nicotinic acid hydrazide produced the corresponding nicotinyl radicals. The time course of radical production was similar for KatG and KatG(S315T), while a lower steady-state level of radicals was produced from nicotinic acid hydrazide. These results support an earlier finding that the peroxidase pathway does not correlate with isoniazid resistance conferred by KatG(S315T). Trace amounts of radicals were detected via the superoxide-dependent pathway. The low level of isoniazid-derived radicals found in the superoxide-dependent pathway may be due to scavenging by superoxide.
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Affiliation(s)
- N L Wengenack
- Department of Biochemistry and Molecular Biology and Section of Hematology Research, Mayo Clinic, Rochester, Minnesota 55905, USA
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33
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Abstract
Short-lived free radicals formed in the reaction of 11 substrates and radiolytically produced hydroxyl radicals were trapped successfully with 5, 5-dimethyl-1-pyrroline-N-oxide (DMPO) in dilute aqueous solution. The in situ radiolysis steady-state ESR spectra of the spin adducts were analyzed to determine accurate ESR parameters for these spin adducts in a uniform environment. Parent alkyl radicals include methyl, ethyl, 1-propyl and 2-propyl (1-methylethyl). Hydroxyalkyl parent radicals were hydroxymethyl, hydroxyethyl, 2-hydroxy-2-propyl (1-methyl-1-hydroxyethyl), 1-hydroxypropyl and 2-hydroxy-2-methylpropyl. Carboxyl radical (carbon dioxide anion, formate radical) and sulfite anion radical were the sigma radicals studied. The DMPO spin adduct of 1-propyl was identified for the first time. For most spin adducts, g factors were also determined for the first time. In DMPO spin adducts of hydroxyalkyl radicals, nitrogen and C(2)-proton hyperfine coupling constants are smaller than those of alkyl radical adducts; the hydroxyalkyl spin adducts possess larger g values than their unsubstituted counterparts. These changes are ascribed to the spread of pi conjugation to include the hydroxyl group. Strong evidence of spin addend-aminoxyl group interaction can be seen in the asymmetrical line shapes in the hydroxyethyl and the hydroxypropyl spin adducts.
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Affiliation(s)
- H Taniguchi
- Department of Veterinary Radiology, Faculty of Agriculture, Yamaguchi University, Yamaguchi 753-8515, Japan
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Dussurget O, Rodriguez M, Smith I. Protective role of the Mycobacterium smegmatis IdeR against reactive oxygen species and isoniazid toxicity. TUBERCLE AND LUNG DISEASE : THE OFFICIAL JOURNAL OF THE INTERNATIONAL UNION AGAINST TUBERCULOSIS AND LUNG DISEASE 2000; 79:99-106. [PMID: 10645447 DOI: 10.1054/tuld.1998.0011] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To understand the mechanism by which IdeR is necessary for maintaining wild type levels of KatG and SodA enzyme activity and normal isoniazid (INH) resistance. DESIGN To identify the step(s) of SodA and KatG function that were affected by the ideR mutation, quantitative western immunoassays and ribonucleic acid (RNA) hybridizations were performed. To see if the increased INH sensitivity of the ideR mutant was caused by lower SodA activity, the Mycobacterium smegmatis sod gene was inactivated. RESULTS The levels of KatG and SodA mRNA and protein in the M. smegmatis IdeR mutant are decreased to approximately 20-40% of those observed in the wild type parent strain. This is quantitatively similar to the decrease in KatG and SodA enzyme activities originally observed in the ideR strain. The M. smegmatis sodA mutant was slightly more sensitive to INH, compared to the wild type strain and was more resistant than the ideR mutant. CONCLUSION IdeR is necessary for full expression of the M. smegmatis katG and sodA genes. It is not yet known whether this protein acts directly at the gene level. The lower levels of SodA contribute slightly to the increased susceptibility to INH of the ideR mutant, but cannot explain the magnitude of the INH sensitivity observed when IdeR is not present. These data suggest that IdeR is a regulator of the cellular stress response, as it has a protective role in cells facing environmental stresses, such as increased levels of reactive oxygen species and INH toxic intermediates. These conclusions do not necessarily apply to IdeR's role in M. tuberculosis physiology, since we have not inactivated its gene in this pathogen.
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Affiliation(s)
- O Dussurget
- Department of Microbiology, Public Health Research Institute, New York, NY 10016, USA
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Brennan RJ, Schiestl RH. The aromatic amine carcinogens o-toluidine and o-anisidine induce free radicals and intrachromosomal recombination in Saccharomyces cerevisiae. Mutat Res 1999; 430:37-45. [PMID: 10592316 DOI: 10.1016/s0027-5107(99)00118-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Aniline-based aromatic amine carcinogens are poorly detected in short-term mutagenicity assays such as the Salmonella reverse mutation (Ames) assay. More information on the mechanism of toxicity of such Salmonella-negative carcinogens is needed. Aniline and o-toluidine are negative in the Ames assay, but induce deletions (DEL) due to intrachromosomal recombination in Saccharomyces cerevisiae with an apparent threshold. We show here that the DEL assay also detects the genotoxic activity of another aromatic amine carcinogen, o-anisidine, which is also negative in the Salmonella assay. We also show that the DEL assay distinguishes between o-anisidine and its non-carcinogenic structural analog 2, 4-dimethoxyaniline. We have investigated whether the ability of the DEL assay to detect the carcinogens and to distinguish between the carcinogen/non-carcinogen pair is linked to rises in intracellular free radical species following exposure to the carcinogens. Toxicity induced by all three compounds was reduced in the presence of the free radical scavenger and antioxidant N-acetyl cysteine, recombination induced by o-anisidine and o-toluidine was also reduced by N-acetyl cysteine. All three compounds induced oxidation of the free radical-sensitive reporter compound dichlorofluorescin diacetate. Superoxide dismutase-deficient strains, however, were hypersensitive to cytotoxicity induced by o-toluidine and o-anisidine but not by the non-carcinogen 2,4-dimethoxyaniline, indicating a different potential for generating superoxide radical between the carcinogens and the non-carcinogen analog. The results indicate that the yeast DEL assay is a useful tool for investigating the genotoxic activity of aromatic amine carcinogens.
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Affiliation(s)
- R J Brennan
- Department of Cancer Cell Biology, Division of Toxicology, Harvard School of Public Health, 665 Huntington Ave., Boston, MA 02115-6021, USA.
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36
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Brennan RJ, Schiestl RH. Free radicals generated in yeast by the Salmonella test-negative carcinogens benzene, urethane, thiourea and auramine O. Mutat Res 1998; 403:65-73. [PMID: 9726007 DOI: 10.1016/s0027-5107(98)00050-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A large fraction of carcinogens score negative in short-term genotoxicity assays such as the Salmonella reverse mutation (Ames) assay. More information is needed about the mechanism of action of such Salmonella-negative carcinogens. Many Salmonella-negative carcinogens induce deletions due to intrachromosomal recombination in Saccharomyces cerevisiae with an apparent threshold. We have previously shown that the Salmonella-negative carcinogens cadmium, aniline, chloroform and carbon tetrachloride generate free radical species in S. cerevisiae. We have further investigated the possible generation of intracellular free radical species by the diverse Salmonella-negative carcinogens benzene, urethane, thiourea and auramine O. The toxicity and recombinagenicity of thiourea and auramine O was reduced in the presence of the free radical scavenger N-acetyl cysteine. N-acetyl cysteine did not protect against toxicity or recombination induced by the Salmonella-positive carcinogens ethyl methane sulfonate, methyl methane sulfonate or nitroquinoline-N-oxide. A strain deficient in the enzyme superoxide dismutase, which catalyses the dismutation of superoxide anion radical, was hypersensitive to killing by benzene, urethane and thiourea. The sod- strain was only slightly more sensitive to the Salmonella-positive carcinogens. Intracellular oxidation of the free radical-sensitive reporter compound dichlorofluorescin diacetate was increased in yeast cultures exposed to benzene, urethane and auramine O; again, the Salmonella mutagens had no effect on oxidation of the dye. These data show that free radical species are produced in Saccharomyces cerevisiae following exposure to benzene, urethane, thiourea and auramine O, and suggest a possible role for oxidative stress is recombination induced by these carcinogens.
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Affiliation(s)
- R J Brennan
- Dept. of Cancer Cell Biology, Harvard School of Public Health, Boston, MA 02115-6021, USA.
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37
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Weglarz L, Koceva-Chyła A. Changes in DNA supercoiling in fibroblasts cultured in the presence of hydralazine. Biochimie 1998; 80:627-30. [PMID: 9810470 DOI: 10.1016/s0300-9084(98)80025-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We have analyzed changes in the supercoiling of nucleoid DNA of murine fibroblasts cultured in the presence of hydralazine. The entire DNA attached to the nuclear matrix was extracted from the cells and sedimented in neutral sucrose density gradients containing ethidium bromide. Nucleoids from cells treated with hydralazine responded to increasing ethidium bromide concentrations in a different way than those from control cultures. That is, supercoiled loops of DNA unwound with lower concentrations of ethidium bromide sedimented less rapidly than those of control cells, indicating that hydralazine reduced the degree of DNA supercoiling. Also, nucleoids from the drug-treated cells resisted the transition from relaxed to positive supercoiling at higher concentrations of ethidium bromide. Changes in nucleoid DNA supercoiling correlated directly with the dose of hydralazine in the fibroblast culture.
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Affiliation(s)
- L Weglarz
- Department of Biochemistry and Chemistry, Silesian Medical Academy, Katowice, Poland
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38
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Rozwarski DA, Grant GA, Barton DH, Jacobs WR, Sacchettini JC. Modification of the NADH of the isoniazid target (InhA) from Mycobacterium tuberculosis. Science 1998; 279:98-102. [PMID: 9417034 DOI: 10.1126/science.279.5347.98] [Citation(s) in RCA: 501] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The preferred antitubercular drug isoniazid specifically targets a long-chain enoyl-acyl carrier protein reductase (InhA), an enzyme essential for mycolic acid biosynthesis in Mycobacterium tuberculosis. Despite the widespread use of this drug for more than 40 years, its precise mode of action has remained obscure. Data from x-ray crystallography and mass spectrometry reveal that the mechanism of isoniazid action against InhA is covalent attachment of the activated form of the drug to the nicotinamide ring of nicotinamide adenine dinucleotide bound within the active site of InhA.
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Affiliation(s)
- D A Rozwarski
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
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39
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Brennan RJ, Schiestl RH. Diaminotoluenes induce intrachromosomal recombination and free radicals in Saccharomyces cerevisiae. Mutat Res 1997; 381:251-8. [PMID: 9434881 DOI: 10.1016/s0027-5107(97)00201-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The carcinogenicity of aniline-based aromatic amines is poorly reflected by their activity in short-term mutagenicity assays such as the Salmonella typhimurium reverse mutation (Ames) assay. More information about the mechanism of action of such carcinogens is needed. Here we report the effects on DEL recombination in Saccharomyces cerevisiae of the carcinogen 2,4-diaminotoluene and its structural isomer 2,6-diaminotoluene, which is reported to be non-carcinogenic. Both compounds are detected as equally mutagenic in the Salmonella assay. In the absence of any external metabolizing system both compounds were recombinagenic in the DEL assay with the carcinogen being a more potent inducer of deletions than the non-carcinogen. In the presence of Aroclor-induced rat liver S9, however, the carcinogen 2,4-diaminotoluene became a 2-fold more potent inducer of deletions, and the non-carcinogen 2,6-diaminotoluene was rendered less toxic and no induced recombination was observed. 2,4-Diaminotoluene is distinguished from its non-carcinogen analog in the DEL assay, therefore, on the basis of a preferential activation of the carcinogen in the presence of a rat liver microsomal metabolizing system. Free radical species are produced by several carcinogens and have been implicated in carcinogenesis. We further investigated whether exposure of yeast to either 2,4-diaminotoluene or 2,6-diaminotoluene resulted in a rise in intracellular free radical species. The effects of the free radical scavenger N-acetylcysteine on toxicity and recombination induced by the two compounds and intracellular oxidation of the free radical-sensitive reporter compound dichlorofluorescin diacetate were studied. Both 2,4- and 2,6-diaminotoluene produced tree radical species in yeast, indicating that the reason for the differential activity of the compounds for induced deletions is not reflected in any difference in the production of free radical species.
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Affiliation(s)
- R J Brennan
- Department of Molecular and Cellular Toxicology, Harvard School of Public Health, Boston, MA 02115-6012, USA.
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40
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Reilly CA, Aust SD. Peroxidase substrates stimulate the oxidation of hydralazine to metabolites which cause single-strand breaks in DNA. Chem Res Toxicol 1997; 10:328-34. [PMID: 9084913 DOI: 10.1021/tx960189l] [Citation(s) in RCA: 157] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Hydrazines are believed to be oxidized by peroxidases to reactive intermediates responsible for a variety of adverse side effects including cancer and drug-induced lupus. However, hydrazines are regarded as a poor peroxidase substrates because inactivation of the peroxidase occurs during oxidation of these compounds. We have investigated the hypothesis that efficient peroxidase substrates, termed mediators, may stimulate peroxidase-catalyzed oxidation of hydrazines to intermediates capable of causing DNA damage. Oxidation of hydralazine by horseradish peroxidase was stimulated, enzyme inactivation was significantly decreased, and DNA strand breakage was enhanced by the addition of chlorpromazine. Similar results were obtained using other peroxidases, mediators, and hydrazine derivatives. DNA damage required the addition of a minimum of 3 equiv of hydrogen peroxide, suggesting the involvement of a three-electron oxidation product of hydralazine in DNA damage. Efficient substrates may therefore play a critical role in peroxidase-dependent oxidative metabolism and subsequent damage to biological macromolecules by certain chemicals.
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Affiliation(s)
- C A Reilly
- Biotechnology Center, Utah State University, Logan 84322-4705, USA
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41
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Evans M, Griffiths H, Lunec J. Reactive Oxygen Species and their Cytotoxic Mechanisms. MECHANISMS OF CELL TOXICITY 1997. [DOI: 10.1016/s1569-2558(08)60271-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Goodwin DC, Aust SD, Grover TA. Free radicals produced during the oxidation of hydrazines by hypochlorous acid. Chem Res Toxicol 1996; 9:1333-9. [PMID: 8951237 DOI: 10.1021/tx960108l] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Hypochlorous acid (HOCl) derived from activated neutrophils and monocytes has been implicated in the activation of hydrazine-containing drugs to toxic intermediates. However, reactive intermediates formed during the reaction between HOCl and these drugs have not been identified. We investigated the oxidation of the hydrazine derivatives isoniazid, iproniazid, and hydralazine by HOCl. The reaction between HOCl and all three hydrazines resulted in O2 consumption, indicating that free radicals were produced, but the rate and extent of O2 consumption were different for each hydrazine. Moreover, reduction of nitroblue tetrazolium (NBT) was observed only during the reaction between HOCl and isoniazid, suggesting that different radical species may be produced from HOCl reaction with each hydrazine. The oxidation of iproniazid by HOCl in the presence of the radical trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) resulted in the formation of a carbon-centered radical adduct. In contrast, the reaction between HOCl and hydralazine resulted in the formation of a nitrogen-centered DMPO radical adduct. The oxidation of isoniazid by HOCl resulted in the formation of two oxygen-centered radical adducts, DMPO-OOH and DMPO-OH. Myeloperoxidase-catalyzed oxidation of these hydrazines in the presence of Cl- and H2O2 produced radical species that were identical to those observed with HOCl. Thus, some of the toxic side effects of these drugs may be the result of the production of free-radical intermediates from reaction with neutrophil-derived oxidants, such as HOCl. The types of radicals produced and the consequences of generating these reactive species are discussed.
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Affiliation(s)
- D C Goodwin
- Biotechnology Center, Utah State University, Logan 84322-4700, USA
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Chatterjee R, Bandyopadhyay U, Mazumdar A, Banerjee RK. Lactoperoxidase-catalysed oxidation of indomethacin, a nonsteroidal antiinflammatory drug, through the formation of a free radical. Biochem Pharmacol 1996; 52:1169-75. [PMID: 8937423 DOI: 10.1016/0006-2952(96)00453-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Lactoperoxidase (LPO, EC 1.11.1.7; donor-H2O2 oxidoreductase) catalyses the oxidation of indomethacin, a nonsteroidal antiinflammatory drug by H2O2 as measured by time-dependent decay of indo-methacin extinction at 280 nm and concurrent appearance of stable oxidation product(s) at 412 nm. From a plot of log Vmax against varying pH of indomethacin oxidation, involvement of an ionizable group of the enzyme having pka = 5.7 could be ascertained for controlling the oxidation process. Spectral studies revealed that LPO-compound II oxidises indomethacin through one-electron transfer and is reduced to the native ferric state as shown by its spectral shift from 430 nm to 412 nm through an isosbestic point at 421 nm. The one-electron oxidation product is a nitrogen-centered free radical detected as a 5,5-dimethyl-l-pyrroline N-oxide (DMPO) adduct (alpha N = 15 G, alpha H beta = 16 G) in electron spin resonance spectroscopy. The free radical is scavenged by reaction with O2 as shown by O2 consumption sensitive to the free-radical trap, DMPO. Binding studies by optical difference spectroscopy indicate that indomethacin binds to LPO with an apparent KD value of 24.5 microM. The free energy change, delta G', for the binding is -26.3 KJ mol-1, suggesting that the interaction is favourable for oxidation. Indomethacin binding remains unaltered by a change of pH from 5.25 to 7.5, presumably because of hydrophobic interaction. The binding is competitive with resorcinol, an aromatic electron donor, showing the KD value to be as high as 100 microM. We suggest that indomethacin interacts at the aromatic donor binding site and is oxidised by one-electron transfer by LPO catalytic intermediates to stable oxidation product(s) through the formation of a free radical.
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Affiliation(s)
- R Chatterjee
- Department of Physiology, Indian Institute of Chemical Biology, Calcutta, India
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Abstract
The heavy metal cadmium is a carcinogen in long-term rodent studies and is a suspect human carcinogen. Cadmium scores negative in the Ames Salmonella mutagenicity assay and in most other short-term genotoxicity assays, but induces deletions in the yeast Saccharomyces cerevisiae. We have investigated whether cadmium induces an oxidative stress in S. cerevisiae which may be responsible for its recombinagenic activity. The free radical scavenger N-acetylcysteine blocked toxicity and recombination induced in S. cerevisiae by cadmium. Yeast strains deficient in the antioxidant defense enzymes superoxide dismutase or gamma-glutamylcysteine synthetase were hypersensitive to cadmium toxicity. Cells grown in the absence of oxygen were more resistant to cadmium. An intracellular free radical-sensitive reporter compound was activated in S. cerevisiae exposed to cadmium. Toxicity or recombination induced by the mutagenic carcinogen methyl methanesulfonate were unaffected in any of the above experiments. These results suggest that the toxicity and recombinagenic activity of cadmium in S. cerevisiae is caused by oxidative stress.
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Affiliation(s)
- R J Brennan
- Department of Molecular and Cellular Toxicology, Harvard School of Public Health, Boston, MA 02115, USA.
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45
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Goodwin DC, Grover TA, Aust SD. Redox mediation in the peroxidase-catalyzed oxidation of aminopyrine: possible implications for drug-drug interactions. Chem Res Toxicol 1996; 9:476-83. [PMID: 8839052 DOI: 10.1021/tx950186t] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Many drugs, industrial pollutants, and other xenobiotics are known to be oxidized by peroxidases to potentially harmful free-radical intermediates. We have examined the possibility that certain compounds, acting as efficient peroxidase substrates, may stimulate the formation of reactive free radicals by acting as mediators of electron transfer reactions (redox mediators). To explore this hypothesis, we have investigated the interaction of two well-known peroxidase substrates, chlorpromazine and aminopyrine. As shown by ESR and UV-visible spectroscopy, chlorpromazine radical was able to oxidize aminopyrine to aminopyrine cation radical. The rate constant for this rapid, pH-dependent, reaction was estimated to be 1 x 10(7) M-1 s-1 at pH 4.5. Transient-state and steady-state kinetic studies both showed that rate constants for chlorpromazine oxidation to its cation radical by horseradish peroxidase (HRP) were about 100-fold greater than for the corresponding HRP-catalyzed oxidation of aminopyrine to its cation radical. When both aminopyrine and chlorpromazine were present with HRP and H2O2, aminopyrine cation radical formation was stimulated 100-fold. Concomitantly, the accumulation of chlorpromazine cation radical was completely inhibited in the presence of aminopyrine. Similar results were obtained when lactoperoxidase, myeloperoxidase, or the myeloperoxidase mimic HOCl were substituted for HRP. These data suggest that chlorpromazine can act as a redox mediator for peroxidase-catalyzed oxidation of aminopyrine and other chemicals. We suggest that some peroxidase substrates, acting as redox mediators, may stimulate the production of toxic free-radical intermediates from various drugs and other xenobiotics. As such, this may have implications for a number of adverse effects caused by these xenobiotic chemicals.
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Affiliation(s)
- D C Goodwin
- Biotechnology Center, Utah State University, Logan 84322-4705, USA
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Adachi K, Matsuhashi T, Nishizawa Y, Usukura J, Popinigis J, Wakabayashi T. Suppression of the hydrazine-induced formation of megamitochondria in the rat liver by coenzyme Q10. Toxicol Pathol 1995; 23:667-76. [PMID: 8772252 DOI: 10.1177/019262339502300604] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effects of coenzyme Q10 (CoQ10) on the hydrazine-induced changes in the structure of mitochondria and those in antioxidant systems of the liver were investigated using rats as experimental animals. Animals were placed on a powdered diet containing 1.0% hydrazine for 7-8 days in the presence or absence of the combined treatment with CoQ10. Results obtained were as follows: (a) treatment of animals with CoQ10 prevented the hydrazine-induced formation of megamitochondria in the liver; (b) changes observed in the liver of the hydrazine-treated animals in comparison to the control were increases in the contents of alpha-tocopherol and CoQ analogs, increases in the levels of lipid peroxidation, decreases in the level of reduced glutathione with increases in that of oxidized glutathione, and increases in the ratio of unsaturated to saturated fatty acids in phospholipid domains of mitochondrial membranes; and (c) administration of CoQ10 to hydrazine-treated animals suppressed enhanced lipid peroxidation and improved lowered adenosine diphosphate/O ratios of mitochondria. The present data suggest that CoQ10 suppresses the hydrazine-induced formation of megamitochondria by scavenging free radicals generated from hydrazine and its metabolites.
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Affiliation(s)
- K Adachi
- Department of Cell Biology and Molecular Pathology, Nagoya University School of Medicine, Japan
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47
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Van Zyl JM, Van der Walt BJ. Apparent hydroxyl radical generation without transition metal catalysis and tyrosine nitration during oxidation of the anti-tubercular drug, isonicotinic acid hydrazide. Biochem Pharmacol 1994; 48:2033-42. [PMID: 7802692 DOI: 10.1016/0006-2952(94)90502-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Aromatic hydroxylation and formation of thiobarbituric acid-reactive substances occurred in a mixture of isonicotinic acid hydrazide (isoniazid) and catalase. Since these reactions were stimulated by phytic acid (a potent metal chelator), rather than inhibited, transition metal-catalysed hydroxyl radical generation was not implicated. Hydroxylation also occurred with isoniazid and phytic acid in the absence of catalase, albeit to a lesser extent. The independent effects of catalase and phytic acid are related to their abilities to catalyse isoniazid oxidation. In the presence of tyrosine, both the isoniazid/phytic acid system and authentic peroxynitrite generated dityrosine. Authentic peroxynitrite, as well as a phytic acid-mediated isoniazid oxidation product, have absorbance maxima at 302 nm. The yield of this isoniazid-derived product increased with pH and in the presence of a superoxide-generating system. A good correlation existed between absorbance at 302 nm and aromatic hydroxylation. Acid-induced decomposition of the 302 nm absorbance in the presence of superoxide dismutase led to the formation of a product absorbing in the same region as peroxynitrite-modified superoxide dismutase (350 nm at acid pH). Catalase catalysed peroxynitrite-mediated, as well as isoniazid/phytic acid-mediated tyrosine nitration, which was accompanied by Compound II formation (ferryl-catalase) in both cases. We postulate that peroxynitrite or a similar species is formed during isoniazid oxidation.
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Affiliation(s)
- J M Van Zyl
- Department of Pharmacology, Medical School, University of Stellenbosch, Tygerberg, South Africa
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48
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van der Walt BJ, van Zyl JM, Kriegler A. Different oxidative pathways of isonicotinic acid hydrazide and its meta-isomer, nicotinic acid hydrazide. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1994; 26:1081-93. [PMID: 7988733 DOI: 10.1016/0020-711x(94)90130-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
1. Superoxide was generated during the auto-oxidation of the antituberculous drug, isonicotinic acid hydrazide (INH), but not with its meta-isomer, nicotinic acid hydrazide (NH). During Fe(3+)-stimulated oxidation of INH and NH, aromatic hydroxylation occurred which was inhibited by the chelating agent, phytic acid. 2. A mixture of myeloperoxidase (MPO) and a hydrazide induced formation of compound III (oxyperoxidase) and aromatic hydroxylation which was stimulated by phytic acid. INH was considerably more potent than NH. 3. Co-oxidation of a hydrazide and thyroxine (T4) in the MPO system resulted in the formation of a pink-coloured product (maximum absorbance at 504 nm) which was more stable with NH than with INH. 4. The hydrazides and Cl- acted synergistically on MPO haem modification when co-oxidised in the MPO-H2O2 system. INH was more destructive than NH. 5. The different oxidative pathways of the hydrazides are consistent with the fact that an acyl intermediate of INH, unlike that of NH, is resonance stabilized.
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Affiliation(s)
- B J van der Walt
- Department of Pharmacology, Medical School, University of Stellenbosch, Tygerberg, South Africa
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Brennan RJ, Swoboda BE, Schiestl RH. Oxidative mutagens induce intrachromosomal recombination in yeast. Mutat Res 1994; 308:159-67. [PMID: 7518043 DOI: 10.1016/0027-5107(94)90151-1] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Active oxygen species are thought to be involved in the causation of a number of diseases including cancers. We have investigated the effect of 5 oxidative mutagens, methyl viologen (paraquat), mitomycin C, phenylhydrazine, cumene hydroperoxide and hydrogen peroxide, on the frequency of both intrachromosomal recombination and interchromosomal recombination in the yeast Saccharomyces cerevisiae. All of the chemicals significantly increased the frequency of intrachromosomal recombination in a dose-dependent manner. Only hydrogen peroxide increased the frequency of interchromosomal recombination at the doses tested in this study. A role for hydroxyl radical (.OH) in the effect of H2O2 on recombination is indicated by the ability of the radical scavenger dimethyl sulfoxide (DMSO) to significantly inhibit the induction of both intrachromosomal and interchromosomal recombination by H2O2. The results presented here give further support for the suitability of intrachromosomal recombination measurements as a short-term test for the detection of mutagens and carcinogens.
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Affiliation(s)
- R J Brennan
- Department of Chemistry, University of Warwick, Coventry, UK
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van der Walt BJ, van Zyl JM, Kriegler A. Aromatic hydroxylation during the myeloperoxidase-oxidase oxidation of hydrazines. Biochem Pharmacol 1994; 47:1039-46. [PMID: 8147902 DOI: 10.1016/0006-2952(94)90415-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Benzoic acid was found to be hydroxylated by a mixture of myeloperoxidase (MPO) and the mycobactericidal drug, isoniazid. Aromatic hydroxylation and formation of compound III (oxyperoxidase) were coincident during the MPO-oxidase oxidation of isoniazid which proceeded without augmentation from the reagent hydrogen peroxide. An intermediate of isoniazid reduced ferric MPO to ferrous MPO which associated with dioxygen to form compound III. Aromatic hydroxylation also occurred in a mixture of isoniazid (or phenylhydrazine) and a ferric salt. Hydroxylations in both the enzymatic and nonenzymatic reaction systems were inhibited by the iron chelator, desferal, as well as by the specific hydroxyl radical scavenger, mannitol. To distinguish between the hydroxylating intermediates in the different reaction systems, the unique properties of the natural antioxidant, phytic acid, were exploited. Phytic acid inhibited aromatic hydroxylation in the Fe(3+)-INH system, which is in accordance with its known properties as a powerful inhibitor of iron-driven reactions (.OH formation). By contrast, phytic acid stimulated hydroxylation in the enzymatic system which was accompanied by a concomitant stimulation in the rate of compound III formation. These events were, however, not directly related to each other. Phytic acid had a direct effect on the redox transformation of isoniazid by stimulating superoxide generation during auto-oxidation of the drug. In addition, phytic acid also facilitated compound III decay in the absence of isoniazid, suggesting that it may also regulate the oxygen affinity of MPO, similar to its effect on the oxygenation of haemoglobin. The data on aromatic hydroxylation in the MPO-isoniazid system do not support a role for .OH in the reaction and may fit the model for the P450 mixed oxidase system.
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Affiliation(s)
- B J van der Walt
- Department of Pharmacology, Medical School, University of Stellenbosch, Tygerberg, South Africa
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