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Chen J, Zhao B, Zou J, Yang J, Yang L, Zhang J, Chen W, Huang D, Zhong Y. Macromolecular NO-Donor Micelles for Targeted and Augmented Chemotherapy against Prostate Cancer. Adv Healthc Mater 2023; 12:e2202266. [PMID: 36415059 DOI: 10.1002/adhm.202202266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 11/01/2022] [Indexed: 11/24/2022]
Abstract
Mitoxantrone (MTO) is clinically utilized for treating hormone-refractory prostate cancer (PCa), however, the therapeutic outcome is far from optimal due to the lack of proper drug carrier as well as the inherent MTO detoxification mechanisms of DNA lesion repair and anti-oxidation. Herein, a bombesin-installed nanoplatform combining the chemotherapeutic MTO and the chemotherapeutic sensitizer of nitric oxide (NO) is developed based on MTO-loaded macromolecular NO-donor-containing polymeric micelles (BN-NMMTO ) for targeted NO-sensitized chemotherapy against PCa. BN-NMMTO actively target and accumulates in PCa sites and are internalized into the tumor cells. The macromolecular NO-donor of BN-NMMTO undergoes a reductive reaction to unleash NO upon intracellular glutathione (GSH), accompanying by micelle swelling and MTO release. The targeted intracellular MTO release induces DNA lesion and reactive oxygen species (ROS) generation in tumor cells without damage to the normal cells, and MTO's cytotoxicity is further augmented by NO release via the inhibition of both DNA repair and anti-oxidation pathways as compared with traditional MTO therapies.
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Affiliation(s)
- Jiaxin Chen
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China
| | - Bingbing Zhao
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China
| | - Junhui Zou
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China
| | - Jiachen Yang
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China
| | - Lifen Yang
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China
| | - Junmei Zhang
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China
| | - Wei Chen
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China.,Engineering Research Center for Smart Pharmaceutical Manufacturing Technologies, Ministry of Education, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China
| | - Dechun Huang
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China.,Engineering Research Center for Smart Pharmaceutical Manufacturing Technologies, Ministry of Education, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China
| | - Yinan Zhong
- Department of Pharmaceutical Engineering, School of Engineering, China Pharmaceutical University, Nanjing, 210009, China
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Role of Kynurenine Pathway in Oxidative Stress during Neurodegenerative Disorders. Cells 2021; 10:cells10071603. [PMID: 34206739 PMCID: PMC8306609 DOI: 10.3390/cells10071603] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/18/2021] [Accepted: 06/24/2021] [Indexed: 12/12/2022] Open
Abstract
Neurodegenerative disorders are chronic and life-threatening conditions negatively affecting the quality of patients’ lives. They often have a genetic background, but oxidative stress and mitochondrial damage seem to be at least partly responsible for their development. Recent reports indicate that the activation of the kynurenine pathway (KP), caused by an activation of proinflammatory factors accompanying neurodegenerative processes, leads to the accumulation of its neuroactive and pro-oxidative metabolites. This leads to an increase in the oxidative stress level, which increases mitochondrial damage, and disrupts the cellular energy metabolism. This significantly reduces viability and impairs the proper functioning of central nervous system cells and may aggravate symptoms of many psychiatric and neurodegenerative disorders. This suggests that the modulation of KP activity could be effective in alleviating these symptoms. Numerous reports indicate that tryptophan supplementation, inhibition of KP enzymes, and administration or analogs of KP metabolites show promising results in the management of neurodegenerative disorders in animal models. This review gathers and systematizes the knowledge concerning the role of metabolites and enzymes of the KP in the development of oxidative damage within brain cells during neurodegenerative disorders and potential strategies that could reduce the severity of this process.
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González Esquivel D, Ramírez-Ortega D, Pineda B, Castro N, Ríos C, Pérez de la Cruz V. Kynurenine pathway metabolites and enzymes involved in redox reactions. Neuropharmacology 2017; 112:331-345. [DOI: 10.1016/j.neuropharm.2016.03.013] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 02/28/2016] [Accepted: 03/06/2016] [Indexed: 11/27/2022]
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Chirilă N. Comparative Study to Determine the Nitrate ion Using Spectrophotometric and Chromatographic Methods. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.protcy.2013.12.540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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5
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Salvatorelli E, Menna P, Paz OG, Chello M, Covino E, Singer JW, Minotti G. The Novel Anthracenedione, Pixantrone, Lacks Redox Activity and Inhibits Doxorubicinol Formation in Human Myocardium: Insight to Explain the Cardiac Safety of Pixantrone in Doxorubicin-Treated Patients. J Pharmacol Exp Ther 2012. [DOI: 10.1124/jpet.112.200568] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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Reszka KJ, Sallans L, Macha S, Brown K, McGraw DW, Kovacic MB, Britigan BE. Airway peroxidases catalyze nitration of the {beta}2-agonist salbutamol and decrease its pharmacological activity. J Pharmacol Exp Ther 2010; 336:440-9. [PMID: 20974700 DOI: 10.1124/jpet.110.170027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
β(2)-agonists are the most effective bronchodilators for the rapid relief of asthma symptoms, but for unclear reasons, their effectiveness may be decreased during severe exacerbations. Because peroxidase activity and nitrogen oxides are increased in the asthmatic airway, we examined whether salbutamol, a clinically important β(2)-agonist, is subject to potentially inactivating nitration. When salbutamol was exposed to myeloperoxidase, eosinophil peroxidase or lactoperoxidase in the presence of hydrogen peroxide (H(2)O(2)) and nitrite (NO(2)(-)), both absorption spectroscopy and mass spectrometry indicated formation of a new metabolite with features expected for the nitrated drug. The new metabolites showed an absorption maximum at 410 nm and pK(a) of 6.6 of the phenolic hydroxyl group. In addition to nitrosalbutamol (m/z 285.14), a salbutamol-derived nitrophenol, formed by elimination of the formaldehyde group, was detected (m/z 255.13) by mass spectrometry. It is noteworthy that the latter metabolite was detected in exhaled breath condensates of asthma patients receiving salbutamol but not in unexposed control subjects, indicating the potential for β(2)-agonist nitration to occur in the inflamed airway in vivo. Salbutamol nitration was inhibited in vitro by ascorbate, thiocyanate, and the pharmacological agents methimazole and dapsone. The efficacy of inhibition depended on the nitrating system, with the lactoperoxidase/H(2)O(2)/NO(2)(-) being the most affected. Functionally, nitrated salbutamol showed decreased affinity for β(2)-adrenergic receptors and impaired cAMP synthesis in airway smooth muscle cells compared with the native drug. These results suggest that under inflammatory conditions associated with asthma, phenolic β(2)-agonists may be subject to peroxidase-catalyzed nitration that could potentially diminish their therapeutic efficacy.
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Affiliation(s)
- Krzysztof J Reszka
- Department of Internal Medicine, Veterans Affairs Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH 45267-0557, USA.
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Abstract
The innate host response system is comprised of various mechanisms for orchestrating host response to microbial infection of the oral cavity. The heterogeneity of the oral cavity and the associated microenvironments that are produced give rise to different chemistries that affect the innate defense system. One focus of this review is on how these spatial differences influence the two major defensive peroxidases of the oral cavity, salivary peroxidase (SPO) and myeloperoxidase (MPO). With hydrogen peroxide (H(2)O(2)) as an oxidant, the defensive peroxidases use inorganic ions to produce antimicrobials that are generally more effective than H(2)O(2) itself. The concentrations of the inorganic substrates are different in saliva vs. gingival crevicular fluid (GCF). Thus, in the supragingival regime, SPO and MPO work in unison for the exclusive production of hypothiocyanite (OSCN(-), a reactive inorganic species), which constantly bathes nascent plaques. In contrast, MPO is introduced to the GCF during inflammatory response, and in that environment it is capable of producing hypochlorite (OCl(-)), a chemically more powerful oxidant that is implicated in host tissue damage. A second focus of this review is on inter-person variation that may contribute to different peroxidase function. Many of these differences are attributed to dietary or smoking practices that alter the concentrations of relevant inorganic species in the oral cavity (e.g.: fluoride, F(-); cyanide, CN(-); cyanate, OCN(-); thiocyanate, SCN(-); and nitrate, NO(3)(-)). Because of the complexity of the host and microflora biology and the associated chemistry, it is difficult to establish the significance of the human peroxidase systems during the pathogenesis of oral diseases. The problem is particularly complex with respect to the gingival sulcus and periodontal pockets (where the very different defensive stratagems of GCF and saliva co-mingle). Despite this complexity, intriguing in vitro and in vivo studies are reviewed here that reveal the interplay between peroxidase function and associated inorganic chemistry.
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Affiliation(s)
- M T Ashby
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019, USA.
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Pandurangappa M, Venkataramanappa Y. Aminophenyl Benzimidazole as a New Reagent for the Estimation of NO2/Nitrite/Nitrate at Trace Level: Application to Environmental Samples. ANAL LETT 2007. [DOI: 10.1080/00032710701606382] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Ghasemi J, Jabbari A, Amini A, Oskoei AG, Abdolahi B. Kinetic Spectrophotometric Determination of Nitrite Based on Its Catalytic Effect on the Oxidation of Methyl Red by Bromate. ANAL LETT 2004. [DOI: 10.1081/al-200026698] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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10
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Corna G, Santambrogio P, Minotti G, Cairo G. Doxorubicin Paradoxically Protects Cardiomyocytes against Iron-mediated Toxicity. J Biol Chem 2004; 279:13738-45. [PMID: 14739295 DOI: 10.1074/jbc.m310106200] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The cardiotoxicity induced by the anticancer anthracycline doxorubicin (DOX) is attributed to reactions between iron and reactive oxygen species (ROS) that lead to oxidative damage. We found that DOX forms ROS in H9c2 cardiomyocytes, as shown by dichlorodihydrofluorescein oxidation and the expression of stress-responsive genes such as catalase or aldose reductase. DOX also increased ferritin levels in these cells, particularly the H subunit. A considerable increase in ferritin mRNA levels showed that DOX acted at transcriptional level, but an additional potential mechanism was identified as the down-regulation of iron regulatory protein-2, post-transcriptional inhibitor of ferritin synthesis. Pretreatment with DOX protected H9c2 cells against the damage induced by subsequent exposure to ferric ammonium citrate, and experiments with (55)Fe revealed that the protection was due to the deposition of iron in ferritin. Cytoprotection was also observed when DOX was replaced by glucose/glucose oxidase, a source of H(2)O(2), thus suggesting that DOX increases ferritin synthesis through the action of ROS. This concept was supported by three more lines of evidence. (i) DOX-induced ferritin synthesis was blocked by N-acetylcysteine, a scavenger of ROS. (ii) Mitoxantrone, a ROS-forming analogue, similarly induced ferritin expression and protected the cells against iron toxicity. (iii) 5-Iminodaunorubicin, an analogue lacking ROS-forming activity, did not induce ferritin synthesis or protect the cells against iron toxicity. These results characterize a paradoxically beneficial link between anthracycline-derived ROS, increased ferritin synthesis, and resistance to iron-mediated damage. The role of iron and ROS in anthracycline-induced cardiotoxicity may, therefore, be more complex than previously believed.
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Affiliation(s)
- Gianfranca Corna
- Institute of General Pathology, University of Milan, Via Mangiagalli 31, 20133 Milan, Italy
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11
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Brück TB, Harvey PJ. Oxidation of mitoxantrone by lactoperoxidase. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1649:154-63. [PMID: 12878034 DOI: 10.1016/s1570-9639(03)00168-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The lactoperoxidase (LPO) catalysed oxidation of mitoxantrone, an anthraquinone type anti-cancer drug, was studied spectrophotometrically under turnover and single turnover conditions with a stopped flow apparatus. With Compound I and Compound II, mitoxantrone formed binding complexes that were deactivated with increasing substrate concentration. The productive second-order rate constants for reduction were 3.6 x 10(6) and 2.2 x 10(4) M(-1) s(-1) for Compound I and Compound II, respectively. Under turnover conditions, Compound II was the steady-state intermediate, but with increasing H2O2, Compound II reacted with H2O2 to form the catalytically inactive intermediate Compound III. Nitrite prevented formation of Compound III by reducing Compound II to the native state. It also modulated the pathway of mitoxantrone oxidation by increasing the level of oxidised metabolites such as MH2(2+) and the novel metabolite MH. The biological implication of drug activation by LPO with nitrite is discussed.
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Affiliation(s)
- Thomas B Brück
- School of Chemical and Life Sciences, University of Greenwich, Central Avenue, Chatham Maritime, Kent ME4 4TB, UK
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12
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DiMeco F, Li KW, Tyler BM, Wolf AS, Brem H, Olivi A. Local delivery of mitoxantrone for the treatment of malignant brain tumors in rats. J Neurosurg 2002; 97:1173-8. [PMID: 12450040 DOI: 10.3171/jns.2002.97.5.1173] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Mitoxantrone is a drug with potent in vitro activity against malignant brain tumor cell lines; however, its effectiveness as a systemic agent has been hampered by poor central nervous system penetration and dose-limiting myelosuppression. To avoid these problems, we incorporated mitoxantrone into biodegradable polymeric wafers to be used for intracranial implantation, a strategy that has been shown to be safe and successful in the treatment of malignant gliomas. The authors investigated the release kinetics, toxicity, distribution, and efficacy of mitoxantrone delivered from intracranially implanted biodegradable wafers in the treatment of 9L gliosarcoma in Fischer 344 rats. METHODS Mitoxantrone released from the biodegradable wafer matrix reached therapeutic drug concentrations in the brain for at least 35 days. Only animals with implanted wafers of the highest drug loading dose (20% mitoxantrone by weight) showed signs of significant toxicity. In three separate efficacy experiments, animals treated with mitoxantrone-loaded biodegradable wafers had significantly improved survival compared with control animals. The combined median survival for each treatment group was the following: 0% mitoxantrone wafers, 19 days; 1%, 30 days, p < 0.0001; 5%, 34 days, p < 0.0001; and 10%, 50 days, p < 0.0001. CONCLUSIONS These findings establish that mitoxantrone delivered from intracranially implanted biodegradable wafers is effective in the treatment of malignant gliomas in rodents and should be considered for future clinical application in humans.
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Affiliation(s)
- Francesco DiMeco
- Department of Neurosurgery, Istituto Nazionale Neurologico C. Besta, Milan, Italy
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Ricoux R, Girgenti E, Sauriat-Dorizon H, Blanchard D, Mahy JP. Regioselective nitration of phenol induced by catalytic antibodies. JOURNAL OF PROTEIN CHEMISTRY 2002; 21:473-7. [PMID: 12523651 DOI: 10.1023/a:1021351120772] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Catalytic antibodies with a metalloporphyrin cofactor represent a new generation of biocatalysts tailored for selective oxidations. Thus monoclonal antibodies, 3A3, were raised against microperoxidase 8 (MP8), and the corresponding 3A3-MP8 complexes were shown previously to have a high peroxidase activity. This paper shows that those complexes also catalyzed efficiently the nitration of phenol into 2- and 4-nitrophenol by NO2- in the presence of H2O2. pH dependence studies suggested that no amino acid from the antibody protein participated in the heterolytic cleavage of the O-O bond of H2O2. The inhibition of the reaction by cyanide and radical scavengers suggested a MP8-mediated peroxidase-like mechanism, involving the reduction of high-valent iron-oxo species by NO2- and phenol producing, respectively, NO2* and phenoxy radicals, which then reacted to give nitrophenols. Finally, the antibody protein appears to have two major roles: (i) it protects MP8 toward oxidative degradations and (ii) it induces a regioselectivity of the reaction toward the formation of 2-nitrophenol.
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Affiliation(s)
- Rémy Ricoux
- Laboratoire de Chimie Bioorganique et bioinorganique, FRE 2127 CNRS, Institut de Chimie Moleculaire d-Orsay, Bât. 420, Université de Paris-sud XI, 91405, Orsay Cedex, France
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Tomiyasu T, Konagayoshi Y, Anazawa K, Sakamoto H. A kinetic method for the determination of nitrite by its catalytic effect on the oxidation of chlorpromazine with nitric acid. ANAL SCI 2001; 17:1437-40. [PMID: 11783795 DOI: 10.2116/analsci.17.1437] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A catalytic spectrophotometric method for the determination of trace amounts of nitrite is proposed. In acidic solution, chlorpromazine (CP) is oxidized by nitric acid to form a red compound, which is further oxidized to a colorless compound. The reaction is accelerated by trace amounts of nitrite and can be followed by measuring the absorbance at 525 nm: nitrite ion is regenerated and multiplied by nitric acid. The absorbance of the reaction increased with an increase in the reaction time, reached a maximum and decreased rapidly. Since the time required for the absorbance to reach the maximum decreased with increasing nitrite concentration, this value was used as the measured parameter for the nitrite determination. Under the optimum experimental conditions (2.3 M nitric acid, 1.2 x 10(-5) M CP, 40 degrees C), nitrite can be determined in the range 0-100 microg l(-1). The relative standard deviations (n = 6) are 4.7 and 1.8% for 40 and 100 microg l(-1) nitrite, respectively. The detection limit of this method (3sigma) is 1.2 microg l(-1). This method was successfully applied to a determination of nitrite in natural water samples.
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Affiliation(s)
- T Tomiyasu
- Department of Earth and Environmental Sciences, Faculty of Science, Kagoshima University, Korimoto, Japan.
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Ricoux R, Boucher JL, Mansuy D, Mahy JP. Microperoxidase 8 catalyzed nitration of phenol by nitrogen dioxide radicals. EUROPEAN JOURNAL OF BIOCHEMISTRY 2001; 268:3783-8. [PMID: 11432746 DOI: 10.1046/j.1432-1327.2001.02288.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Microperoxidase 8 (MP8) is a heme octapeptide obtained by hydrolytic digestion of horse heart cytochrome c. At pH below 9, the heme iron is axially coordinated to the imidazole side chain of His18 and to a water molecule. Replacement of this weak ligand by H2O2 allows the formation of high-valent iron-oxo species which are responsible for both peroxidase-like and cytochrome P450-like activities of MP8. This paper shows that MP8 is able to catalyze the nitration of phenol by nitrite. The reaction requires H2O2 and is inhibited by ligands having a high affinity for the iron, catalase and radical scavengers. This suggests that the nitrating species could be NO2* radicals formed by the oxidation of nitrite by high-valent iron-oxo species. This new activity of MP8 opens a new access to nitro-aromatic compounds under mild conditions and validates the use of this minienzyme to mimick heme peroxidases, especially in the reactions of NO-derived species with biomolecules under oxidative stress conditions.
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Affiliation(s)
- R Ricoux
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, UMR 8601 CNRS, Université Paris V, France
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Brück TB, Fielding RJ, Symons MC, Harvey PJ. Mechanism of nitrite-stimulated catalysis by lactoperoxidase. EUROPEAN JOURNAL OF BIOCHEMISTRY 2001; 268:3214-22. [PMID: 11389723 DOI: 10.1046/j.1432-1327.2001.02213.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The reactions of lactoperoxidase (LPO) intermediates compound I, compound II and compound III, with nitrite (NO2(-)) were investigated. Reduction of compound I by NO2(-) was rapid (k2 = 2.3 x 10(7) M(-1) x s(-1); pH = 7.2) and compound II was not an intermediate, indicating that NO2* radicals are not produced when NO2(-) reacts with compound I. The second-order rate constant for the reaction of compound II with NO2(-) at pH = 7.2 was 3.5 x 10(5) M(-1) x s(-1). The reaction of compound III with NO2(-) exhibited saturation behaviour when the observed pseudo first-order rate constants were plotted against NO2(-) concentrations and could be quantitatively explained by the formation of a 1 : 1 ratio compound III/NO2(-) complex. The Km of compound III for NO2(-) was 1.7 x 10(-4) M and the first-order decay constant of the compound III/ NO2(-) complex was 12.5 +/- 0.6 s(-1). The second-order rate constant for the reaction of the complex with NO2(-) was 3.3 x 10(3) M(-1) x s(-1). Rate enhancement by NO2(-) does not require NO2* as a redox intermediate. NO2(-) accelerates the overall rate of catalysis by reducing compound II to the ferric state. With increasing levels of H2O2, there is an increased tendency for the catalytically dead-end intermediate compound III to form. Under these conditions, the 'rescue' reaction of NO2(-) with compound III to form compound II will maintain the peroxidatic cycle of the enzyme.
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Affiliation(s)
- T B Brück
- Department of Chemical and Life Sciences, University of Greenwich, London, UK
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17
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Wagner BA, Buettner GR, Oberley LW, Darby CJ, Burns CP. Myeloperoxidase is involved in H2O2-induced apoptosis of HL-60 human leukemia cells. J Biol Chem 2000; 275:22461-9. [PMID: 10801811 DOI: 10.1074/jbc.m001434200] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We examined the mechanism of H(2)O(2)-induced cytotoxicity and its relationship to oxidation in human leukemia cells. The HL-60 promyelocytic leukemia cell line was sensitive to H(2)O(2), and at concentrations up to about 20-25 micrometer, the killing was mediated by apoptosis. There was limited evidence of lipid peroxidation, suggesting that the effects of H(2)O(2) do not involve hydroxyl radical. When HL-60 cells were exposed to H(2)O(2) in the presence of the spin trap alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (POBN), we detected a 12-line electron paramagnetic resonance spectrum assigned to the POBN/POBN(.) N-centered spin adduct previously described in peroxidase-containing cell-free systems. Generation of this radical by HL-60 cells had the same H(2)O(2) concentration dependence as initiation of apoptosis. In contrast, studies with the K562 human erythroleukemia cell line, which is often used for comparison with the HL-60, and with high passaged HL-60 cells (spent HL-60) studied under the same conditions failed to generate POBN(.). Cellular levels of antioxidant enzymes superoxide dismutase, glutathione peroxidase, and catalase did not explain the differences between these cell lines. Interestingly, the K562 and spent HL-60 cells, which did not generate the radical, also failed to undergo H(2)O(2)-induced apoptosis. Based on this we reasoned that the difference in H(2)O(2)-induced apoptosis might be due to the enzyme myeloperoxidase. Only the apoptosis-manifesting HL-60 cells contained appreciable immunoreactive protein or enzymatic activity of this cellular enzyme. When HL-60 cells were incubated with methimazole or 4-aminobenzoic acid hydrazide, which are inhibitors of myeloperoxidase, they no longer underwent H(2)O(2)-induced apoptosis. Hypochlorous acid stimulated apoptosis in both HL-60 and spent HL-60 cells, indicating that another oxidant generated by myeloperoxidase induces apoptosis and that it may be the direct mediator of H(2)O(2)-induced apoptosis. Taken together these observations indicate that H(2)O(2)-induced apoptosis in the HL-60 human leukemia cell is mediated by myeloperoxidase and is linked to a non-Fenton oxidative event marked by POBN(.).
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Affiliation(s)
- B A Wagner
- Departments of Medicine and Radiology (Free Radical and Radiation Biology Graduate Program), The University of Iowa College of Medicine and The University of Iowa Cancer Center, Iowa City, Iowa 52242, USA
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Zatar NA, Abu-Eid MA, Eid AF. Spectrophotometric determination of nitrite and nitrate using phosphomolybdenum blue complex. Talanta 1999; 50:819-26. [DOI: 10.1016/s0039-9140(99)00152-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/1999] [Revised: 04/26/1999] [Accepted: 05/03/1999] [Indexed: 12/01/2022]
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Reszka KJ, Matuszak Z, Chignell CF, Dillon J. Oxidation of biological electron donors and antioxidants by a reactive lactoperoxidase metabolite from nitrite (NO2-): an EPR and spin trapping study. Free Radic Biol Med 1999; 26:669-78. [PMID: 10218656 DOI: 10.1016/s0891-5849(98)00244-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We report that a lactoperoxidase (LPO) metabolite derived from nitrite (NO2-) catalyses one-electron oxidation of biological electron donors and antioxidants such as NADH, NADPH, cysteine, glutathione, ascorbate, and Trolox C. The radical products of the reaction have been detected and identified using either direct EPR or EPR combined with spin trapping. While LPO/H2O2 alone generated only minute amounts of radicals from these compounds, the yield of radicals increased sharply when nitrite was also present. In aerated buffer (pH 7) the nitrite-dependent oxidation of NAD(P)H by LPO/H2O2 produced superoxide radical, O2*-, which was detected as a DMPO/*O2H adduct. We propose that in the LPO/H2O2/NO2-/biological electron donor systems the nitrite functions as a catalyst because of its preferential oxidation by LPO to a strongly oxidizing metabolite, most likely a nitrogen dioxide radical *NO2, which then reacts with the biological substrates more efficiently than does LPO/H2O2 alone. Because both nitrite and peroxidase enzymes are ubiquitous our observations point at a possible mechanism through which nitrite might exert its biological and cytotoxic action in vivo, and identify some of the physiological targets which might be affected by the peroxidase/H2O2/nitrite systems.
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Affiliation(s)
- K J Reszka
- Department of Ophthalmology, Columbia University, New York, NY, USA.
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Gutierrez-Correa J, Stoppani AO. Inactivation of myocardial dihydrolipoamide dehydrogenase by myeloperoxidase systems: effect of halides, nitrite and thiol compounds. Free Radic Res 1999; 30:105-17. [PMID: 10193578 DOI: 10.1080/10715769900300111] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Dihydrolipoamide dehydrogenase (LADH) lipoamide reductase activity decreased whereas enzyme diaphorase activity increased after LADH treatment with myeloperoxidase (MPO) dependent systems (MPO/H2O2/halide, MPO/NADH/halide and MPO/H2O2/nitrite systems. LADH inactivation was a function of the composition of the inactivating system and the incubation time. Chloride, iodide, bromide, and the thiocyanate anions were effective complements of the MPO/H2O2 system. NaOCl inactivated LADH, thus supporting hypochlorous acid (HOCl) as putative agent of the MPO/H2O2/NaCl system. NaOCl and the MPO/H2O2/NaCl system oxidized LADH thiols and NaOCl also oxidized LADH methionine and tyrosine residues. LADH inactivation by the MPO/NADH/halide systems was prevented by catalase and enhanced by superoxide dismutase, in close agreement with H2O2 production by the LADH/NADH system. Similar effects were obtained with lactoperoxidase and horse-radish peroxidase supplemented systems. L-cysteine, N-acetylcysteine, penicillamine, N-(2-mercaptopropionylglycine), Captopril and taurine protected LADH against MPO systems and NaOCl. The effect of the MPO/H2O2/NaNO2 system was prevented by MPO inhibitors (sodium azide, isoniazid, salicylhydroxamic acid) and also by L-cysteine, L-methionine, L-tryptophan, L-tyrosine, L-histidine and reduced glutathione. The summarized observations support the hypothesis that peroxidase-generated "reactive species" oxidize essential thiol groups at LADH catalytic site.
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Affiliation(s)
- J Gutierrez-Correa
- Bioenergetics Research Centre, School of Medicine, University of Buenos Aires, Paraguay, Argentina
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