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Krawic C, Zhitkovich A. Chemical mechanisms of DNA damage by carcinogenic chromium(VI). ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2022; 96:25-46. [PMID: 36858775 PMCID: PMC10069994 DOI: 10.1016/bs.apha.2022.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hexavalent chromium is a firmly established human carcinogen with documented exposures in many professional groups. Environmental exposure to Cr(VI) is also a significant public health concern. Cr(VI) exists in aqueous solutions as chromate anion that is unreactive with DNA and requires reductive activation inside the cells to produce genotoxic and mutagenic effects. Reduction of Cr(VI) in cells is nonenzymatic and in vivo principally driven by ascorbate with a secondary contribution from nonprotein thiols glutathione and cysteine. In addition to its much faster rate of reduction, ascorbate-driven metabolism avoids the formation of Cr(V) which is the first intermediate in Cr(VI) reduction by thiols. The end-product of Cr(VI) reduction is Cr(III) which forms several types of Cr-DNA adducts that are collectively responsible for all mutagenic and genotoxic effects in Cr(VI) reactions with ascorbate and thiols. Some Cr(V) forms can react with H2O2 to produce DNA-oxidizing peroxo species although this genotoxic pathway is suppressed in cells with physiological levels of ascorbate. Chemical reactions of Cr(VI) with ascorbate or thiols lack directly DNA-oxidizing metabolites. The formation of oxidative DNA breaks in early studies of these reactions was caused by iron contamination. Production of Cr(III)-DNA adducts in cells showed linear dose-dependence irrespective of the predominant reduction pathway and their processing by mismatch repair generated more toxic secondary genetic lesions in euchromatin. Overall, Cr(III)-DNA adduction is the dominant pathway for the formation of genotoxic and mutagenic DNA damage by carcinogenic Cr(VI).
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Affiliation(s)
- Casey Krawic
- Department of Pathology and Laboratory Medicine, Legorreta Cancer Center, Brown University, Providence, RI, United States
| | - Anatoly Zhitkovich
- Department of Pathology and Laboratory Medicine, Legorreta Cancer Center, Brown University, Providence, RI, United States.
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2
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Schumacher P, Fischer F, Sann J, Walter D, Hartwig A. Impact of Nano- and Micro-Sized Chromium(III) Particles on Cytotoxicity and Gene Expression Profiles Related to Genomic Stability in Human Keratinocytes and Alveolar Epithelial Cells. NANOMATERIALS 2022; 12:nano12081294. [PMID: 35458002 PMCID: PMC9029936 DOI: 10.3390/nano12081294] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/31/2022] [Accepted: 04/05/2022] [Indexed: 02/01/2023]
Abstract
Exposure to Cr(VI) compounds has been consistently associated with genotoxicity and carcinogenicity, whereas Cr(III) is far less toxic, due to its poor cellular uptake. However, contradictory results have been published in relation to particulate Cr2O3. The aim of the present study was to investigate whether Cr(III) particles exerted properties comparable to water soluble Cr(III) or to Cr(VI), including two nano-sized and one micro-sized particles. The morphology and size distribution were determined by TEM, while the oxidation state was analyzed by XPS. Chromium release was quantified via AAS, and colorimetrically differentiated between Cr(VI) and Cr(III). Furthermore, the toxicological fingerprints of the Cr2O3 particles were established using high-throughput RT-qPCR and then compared to water-soluble Cr(VI) and Cr(III) in A549 and HaCaT cells. Regarding the Cr2O3 particles, two out of three exerted only minor or no toxicity, and the gene expression profiles were comparable to Cr(III). However, one particle under investigation released considerable amounts of Cr(VI), and also resembled the toxicity profiles of Cr(VI); this was also evident in the altered gene expression related to DNA damage signaling, oxidative stress response, inflammation, and cell death pathways. Even though the highest toxicity was found in the case of the smallest particle, size did not appear to be the decisive parameter, but rather the purity of the Cr(III) particles with respect to Cr(VI) content.
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Affiliation(s)
- Paul Schumacher
- Department of Food Chemistry and Toxicology, Institute of Applied Biosciences (IAB), Karlsruhe Institute of Technology (KIT), Adenauerring 20a, 76131 Karlsruhe, Germany; (P.S.); (F.F.)
| | - Franziska Fischer
- Department of Food Chemistry and Toxicology, Institute of Applied Biosciences (IAB), Karlsruhe Institute of Technology (KIT), Adenauerring 20a, 76131 Karlsruhe, Germany; (P.S.); (F.F.)
| | - Joachim Sann
- Institute of Physical Chemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 17, 35392 Giessen, Germany;
- Center for Materials Research (LaMa/ZfM), Justus-Liebig-University Giessen, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - Dirk Walter
- Laboratories of Chemistry and Physics, Institute of Occupational and Social Medicine, Justus-Liebig-University Giessen, Aulweg 129, 35392 Giessen, Germany;
- Institute of Inorganic and Analytical Chemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Andrea Hartwig
- Department of Food Chemistry and Toxicology, Institute of Applied Biosciences (IAB), Karlsruhe Institute of Technology (KIT), Adenauerring 20a, 76131 Karlsruhe, Germany; (P.S.); (F.F.)
- Correspondence:
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3
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Pavesi T, Moreira JC. Mechanisms and individuality in chromium toxicity in humans. J Appl Toxicol 2020; 40:1183-1197. [DOI: 10.1002/jat.3965] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 02/10/2020] [Accepted: 02/23/2020] [Indexed: 12/18/2022]
Affiliation(s)
- Thelma Pavesi
- Centro de Estudos da Saúde do Trabalhador e Ecologia HumanaEscola Nacional de Saúde Pública, Fundação Oswaldo Cruz Rio de Janeiro Brazil
| | - Josino Costa Moreira
- Centro de Estudos da Saúde do Trabalhador e Ecologia HumanaEscola Nacional de Saúde Pública, Fundação Oswaldo Cruz Rio de Janeiro Brazil
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4
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Teaching Chemical Kinetics with Dynamic Simulations. TRENDS IN CHEMISTRY 2019. [DOI: 10.1016/j.trechm.2019.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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5
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Bader K, Schlindwein SH, Gudat D, van Slageren J. Molecular qubits based on potentially nuclear-spin-free nickel ions. Phys Chem Chem Phys 2017; 19:2525-2529. [PMID: 28058424 DOI: 10.1039/c6cp08161d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Molecular qubits with the longest coherence times thus far are based on nuclear-spin-carrying central ions. These nuclear spins can cause quantum state leakage, which is detrimental to quantum algorithm performance. We present two novel molecular qubits based on potentially nuclear spin-free Ni in the formal oxidation state 3+. (d20-PPh4)[Ni(mnt)2] (Ni-mnt, mnt2- = maleonitrile-1,2-dithiolate) possesses a coherence time of up to 38.7 μs at 7 K. Functionalization of the dithiolate ligand decreases the coherence time by a factor of only four in (HNEt3)[Ni(dip)2] (Ni-dip, dip2- = 3-(diphenylphosphoryl)-methylbenzene-1,2-dithiolate), indicating that monoanionic Ni-dithiolene complexes are promising and robust building blocks for polynuclear molecular qubit gates.
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Affiliation(s)
- K Bader
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany.
| | - S H Schlindwein
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - D Gudat
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - J van Slageren
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany. and Center for Integrated Quantum Science and Technology (IQST), Stuttgart/Ulm, Germany
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6
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Spectroscopic characterization of genotoxic chromium(V) peptide complexes: Oxidation of Chromium(III) triglycine, tetraglycine and pentaglycine complexes. J Inorg Biochem 2016; 162:227-237. [DOI: 10.1016/j.jinorgbio.2016.06.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 06/07/2016] [Accepted: 06/14/2016] [Indexed: 11/23/2022]
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7
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Van Doorslaer S, Beirinckx Q, Nys K, Mangiameli MF, Cuypers B, Callens F, Vrielinck H, González JC. EPR and DFT analysis of biologically relevant chromium(V) complexes with d-glucitol and d-glucose. J Inorg Biochem 2016; 162:216-226. [PMID: 27460210 DOI: 10.1016/j.jinorgbio.2016.07.012] [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: 10/30/2015] [Revised: 07/15/2016] [Accepted: 07/18/2016] [Indexed: 10/21/2022]
Abstract
1,2-diolato ligands, such as carbohydrates and glycoproteins, tend to stabilize chromium(V), thus forming important intermediates that have been implicated in the genotoxicity of Cr(VI). Since many years, room-temperature continuous-wave electron paramagnetic resonance (EPR) at X-band microwave frequencies has been used as a standard characterization tool to study chromium(V) intermediates formed during the reduction of Cr(VI) in the presence of biomolecules. In this work, the added value is tested of using a combination of pulsed and high-field EPR techniques with density functional theory computations to unravel the nature of Cr(V) complexes with biologically relevant chelators, such as carbohydrates. The study focuses on the oxidochromium(V) complexes formed during reduction of potassium dichromate with glutathione in the presence of the monosaccharide d-glucose or the polyalcohol d-glucitol. It is shown that although the presence of a multitude of Cr(V) intermediates may hamper a complete structural determination, the combined EPR and DFT approach reveals unambiguously the effect of freezing on the location of the counterions, the gradual replacement of water ligands by the diols, and the preference of Cr(V) to bind certain conformers.
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Affiliation(s)
- Sabine Van Doorslaer
- University of Antwerp, Department of Physics, Universiteitsplein 1, B-2610 Antwerp, Belgium.
| | - Quinten Beirinckx
- University of Antwerp, Department of Physics, Universiteitsplein 1, B-2610 Antwerp, Belgium.
| | - Kevin Nys
- University of Antwerp, Department of Physics, Universiteitsplein 1, B-2610 Antwerp, Belgium.
| | - María Florencia Mangiameli
- Universidad National de Rosario, Departamento de Químico Física - Área Química General, Facultad de Ciencias Bioquímicas y Farmacéuticas, IQUIR-CONICET, Suipacha 531, Rosario, Santa Fe, Argentina.
| | - Bert Cuypers
- University of Antwerp, Department of Physics, Universiteitsplein 1, B-2610 Antwerp, Belgium.
| | - Freddy Callens
- Ghent University, Dept. of Solid State Sciences, Krijgslaan 281-S1, B-9000 Ghent, Belgium.
| | - Henk Vrielinck
- Ghent University, Dept. of Solid State Sciences, Krijgslaan 281-S1, B-9000 Ghent, Belgium.
| | - Juan Carlos González
- University of Antwerp, Department of Physics, Universiteitsplein 1, B-2610 Antwerp, Belgium; Universidad National de Rosario, Departamento de Químico Física - Área Química General, Facultad de Ciencias Bioquímicas y Farmacéuticas, IQUIR-CONICET, Suipacha 531, Rosario, Santa Fe, Argentina.
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Hu X, Chai J, Liu Y, Liu B, Yang B. Probing chromium(III) from chromium(VI) in cells by a fluorescent sensor. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2016; 153:505-509. [PMID: 26414552 DOI: 10.1016/j.saa.2015.09.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Revised: 09/09/2015] [Accepted: 09/20/2015] [Indexed: 06/05/2023]
Abstract
Cellular uptake of Cr(VI), followed by its reduction to Cr(III) with the formation of kinetically inert Cr(III) complexes, is a complex process. To better understand its physiological and pathological functions, efficient methods for the monitoring of Cr(VI) are desired. In this paper a selective fluorescent probe L, rhodamine hydrazide bearing a benzo[b]furan-2-carboxaldehyde group, was demonstrated as a red chemosensor for Cr(III) at about 586 nm. This probe has been used to probe Cr(III) which is reduced from Cr(VI) by reductants such as glutathione (GSH), vitamin C, cysteine (Cys), H2O2 and Dithiothreitol (DTT) by fluorescence spectra. Cr(VI) metabolism in vivo is primarily driven by Vc and GSH. Vc could reduce CrO4(2-) to Cr(III) in a faster rate than GSH. The indirectly detection limit for Cr(VI) by L+GSH system was determined to be 0.06 μM at pH=6.2. Moreover, the confocal microscopy image experiments indicated that Cr(VI) can be reduced to Cr(III) inside cells rapidly and the resulted Cr(III) can be captured and imaged timely by L.
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Affiliation(s)
- Xiangquan Hu
- Institute of Molecular Science, Key Laboratory of Chemical Biology of Molecular Engineering of Education Ministry, Shanxi University, Taiyuan 030006, China
| | - Jie Chai
- Institute of Molecular Science, Key Laboratory of Chemical Biology of Molecular Engineering of Education Ministry, Shanxi University, Taiyuan 030006, China
| | - Yanfei Liu
- Institute of Molecular Science, Key Laboratory of Chemical Biology of Molecular Engineering of Education Ministry, Shanxi University, Taiyuan 030006, China
| | - Bin Liu
- Institute of Molecular Science, Key Laboratory of Chemical Biology of Molecular Engineering of Education Ministry, Shanxi University, Taiyuan 030006, China.
| | - Binsheng Yang
- Institute of Molecular Science, Key Laboratory of Chemical Biology of Molecular Engineering of Education Ministry, Shanxi University, Taiyuan 030006, China.
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9
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Wrobel K, Corrales Escobosa AR, Gonzalez Ibarra AA, Mendez Garcia M, Yanez Barrientos E, Wrobel K. Mechanistic insight into chromium(VI) reduction by oxalic acid in the presence of manganese(II). JOURNAL OF HAZARDOUS MATERIALS 2015; 300:144-152. [PMID: 26177490 DOI: 10.1016/j.jhazmat.2015.06.066] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 05/06/2015] [Accepted: 06/30/2015] [Indexed: 06/04/2023]
Abstract
Over the past few decades, reduction of hexavalent chromium (Cr(VI)) has been studied in many physicochemical contexts. In this research, we reveal the mechanism underlying the favorable effect of Mn(II) observed during Cr(VI) reduction by oxalic acid using liquid chromatography with spectrophotometric diode array detector (HPLC-DAD), nitrogen microwave plasma atomic emission spectrometry (HPLC-MP-AES), and high resolution mass spectrometry (ESI-QTOFMS). Both reaction mixtures contained potassium dichromate (0.67 mM Cr(VI)) and oxalic acid (13.3mM), pH 3, one reaction mixture contained manganese sulfate (0.33 mM Mn(II)). In the absence of Mn(II) only trace amounts of reaction intermediates were generated, most likely in the following pathways: (1) Cr(VI)→ Cr(IV) and (2) Cr(VI)+Cr(IV)→ 2Cr(V). In the presence of Mn(II), the active reducing species appeared to be Mn(II) bis-oxalato complex (J); the proposed reaction mechanism involves a one-electron transfer from J to any chromium compound containing CrO bond, which is reduced to CrOH, and the generation of Mn(III) bis-oxalato complex (K). Conversion of K to J was observed, confirming the catalytic role of Mn(II). Since no additional acidification was required, the results obtained in this study may be helpful in designing a new, environmentally friendly strategy for the remediation of environments contaminated with Cr(VI).
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Affiliation(s)
- Katarzyna Wrobel
- Chemistry Department, Division of Natural and Exact Sciences, University of Guanajuato, L. de Retana 5, 36000 Guanajuato, Mexico
| | - Alma Rosa Corrales Escobosa
- Chemistry Department, Division of Natural and Exact Sciences, University of Guanajuato, L. de Retana 5, 36000 Guanajuato, Mexico
| | - Alan Alexander Gonzalez Ibarra
- Chemistry Department, Division of Natural and Exact Sciences, University of Guanajuato, L. de Retana 5, 36000 Guanajuato, Mexico
| | - Manuel Mendez Garcia
- Chemistry Department, Division of Natural and Exact Sciences, University of Guanajuato, L. de Retana 5, 36000 Guanajuato, Mexico
| | - Eunice Yanez Barrientos
- Chemistry Department, Division of Natural and Exact Sciences, University of Guanajuato, L. de Retana 5, 36000 Guanajuato, Mexico
| | - Kazimierz Wrobel
- Chemistry Department, Division of Natural and Exact Sciences, University of Guanajuato, L. de Retana 5, 36000 Guanajuato, Mexico.
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10
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Wu LE, Levina A, Harris HH, Cai Z, Lai B, Vogt S, James DE, Lay PA. Carcinogenic Chromium(VI) Compounds Formed by Intracellular Oxidation of Chromium(III) Dietary Supplements by Adipocytes. Angew Chem Int Ed Engl 2015; 55:1742-5. [PMID: 26696553 DOI: 10.1002/anie.201509065] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Indexed: 12/31/2022]
Abstract
Chromium(III) nutritional supplements are widely consumed for their purported antidiabetic activities. X-ray fluorescence microscopy (XFM) and X-ray absorption near-edge structure (XANES) studies have now shown that non-toxic doses of [Cr3 O(OCOEt)6 (OH2 )3 ](+) (A), a prospective antidiabetic drug that undergoes similar H2 O2 induced oxidation reactions in the blood as other Cr supplements, was also oxidized to carcinogenic Cr(VI) and Cr(V) in living cells. Single adipocytes treated with A had approximately 1 μm large Cr hotspots containing Cr(III) , Cr(V) , and Cr(VI) (primarily Cr(VI) thiolates) species. These results strongly support the hypothesis that the antidiabetic activity of Cr(III) and the carcinogenicity of Cr(VI) compounds arise from similar mechanisms involving highly reactive Cr(VI) and Cr(V) intermediates, and highlight concerns over the safety of Cr(III) nutritional supplements.
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Affiliation(s)
- Lindsay E Wu
- School of Chemistry, The University of Sydney, NSW, 2006, Australia.,Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, NSW, 2010, Australia.,School of Medical Sciences, UNSW Australia, NSW, 2052, Australia
| | - Aviva Levina
- School of Chemistry, The University of Sydney, NSW, 2006, Australia
| | - Hugh H Harris
- School of Chemistry, The University of Sydney, NSW, 2006, Australia.,School of Chemistry and Physics, The University of Adelaide, SA, 5005, Australia
| | - Zhonghou Cai
- Advanced Photon Source, X-ray Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Barry Lai
- Advanced Photon Source, X-ray Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Stefan Vogt
- Advanced Photon Source, X-ray Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - David E James
- Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, NSW, 2010, Australia.,Charles Perkins Centre, The University of Sydney, NSW, 2006, Australia
| | - Peter A Lay
- School of Chemistry, The University of Sydney, NSW, 2006, Australia.
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11
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Wu LE, Levina A, Harris HH, Cai Z, Lai B, Vogt S, James DE, Lay PA. Carcinogenic Chromium(VI) Compounds Formed by Intracellular Oxidation of Chromium(III) Dietary Supplements by Adipocytes. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201509065] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Lindsay E. Wu
- School of Chemistry; The University of Sydney; NSW 2006 Australia
- Garvan Institute of Medical Research; 384 Victoria St Darlinghurst NSW 2010 Australia
- School of Medical Sciences; UNSW Australia; NSW 2052 Australia
| | - Aviva Levina
- School of Chemistry; The University of Sydney; NSW 2006 Australia
| | - Hugh H. Harris
- School of Chemistry; The University of Sydney; NSW 2006 Australia
- School of Chemistry and Physics; The University of Adelaide; SA 5005 Australia
| | - Zhonghou Cai
- Advanced Photon Source; X-ray Science Division; Argonne National Laboratory; Argonne IL 60439 USA
| | - Barry Lai
- Advanced Photon Source; X-ray Science Division; Argonne National Laboratory; Argonne IL 60439 USA
| | - Stefan Vogt
- Advanced Photon Source; X-ray Science Division; Argonne National Laboratory; Argonne IL 60439 USA
| | - David E. James
- Garvan Institute of Medical Research; 384 Victoria St Darlinghurst NSW 2010 Australia
- Charles Perkins Centre; The University of Sydney; NSW 2006 Australia
| | - Peter A. Lay
- School of Chemistry; The University of Sydney; NSW 2006 Australia
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12
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Mangiameli MF, González JC, Bellú S, Bertoni F, Sala LF. Redox and complexation chemistry of the CrVI/CrV-D-glucaric acid system. Dalton Trans 2015; 43:9242-54. [PMID: 24816781 DOI: 10.1039/c4dt00717d] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
When an excess of uronic acid over Cr(VI) is used, the oxidation of D-glucaric acid (Glucar) by Cr(VI) yields D-arabinaric acid, CO2 and Cr(III)-Glucar complex as final redox products. The redox reaction involves the formation of intermediate Cr(IV) and Cr(V) species. The reaction rate increases with [H(+)] and [substrate]. The experimental results indicated that Cr(IV) and Cr(V) are very reactive intermediates since their disappearance rates are much faster than Cr(VI). Cr(IV) and Cr(V) intermediates are involved in fast steps and do not accumulate in the redox reaction of the mixture Cr(VI)-Glucar. Kinetic studies show that the redox reaction between Glucar and Cr(VI) proceeds through a mechanism combining one- and two-electron pathways: Cr(VI) → Cr(IV) → Cr(II) and Cr(VI) → Cr(IV) → Cr(III). After the redox reaction, results show a slow hydrolysis of the Cr(III)-Glucar complex into [Cr(OH2)6](3+). The proposed mechanism is supported by the observation of free radicals, CrO2(2+) (superoxo-Cr(III) ion) and oxo-Cr(V)-Glucar species as reaction intermediates. The continuous-wave electron paramagnetic resonance, CW-EPR, spectra show that five-coordinate oxo-Cr(V) bischelates are formed at pH ≤ 4 with the aldaric acid bound to oxo-Cr(V) through the carboxylate and the α-OH group. A different oxo-Cr(V) species with Glucar was detected at pH 6.0. The high g(iso) value for the last species suggests a mixed coordination species, a five-coordinated oxo-Cr(V) bischelate with one molecule of Glucar acting as a bi-dentate ligand, using the 2-hydroxycarboxylate group, and a second molecule of Glucar with any vic-diolate sites. At pH 7.5 only a very weak EPR signal was observed, which may point to instability of these complexes. This behaviour contrasts with oxo-Cr(V)-uronic species, and must thus be related to the Glucar acyclic structure. In vitro, our studies on the chemistry of oxo-Cr(V)-Glucar complexes can provide information on the nature of the species that are likely to be stabilized in vivo.
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Affiliation(s)
- María Florencia Mangiameli
- Área Química General, Departamento de Químico-Física, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, UNR, Instituto de Química de Rosario-CONICET, Suipacha 531, S2002LRK, Rosario, Santa Fe, Argentina.
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13
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Levina A, McLeod AI, Pulte A, Aitken JB, Lay PA. Biotransformations of Antidiabetic Vanadium Prodrugs in Mammalian Cells and Cell Culture Media: A XANES Spectroscopic Study. Inorg Chem 2015; 54:6707-18. [PMID: 25906315 PMCID: PMC4511291 DOI: 10.1021/ic5028948] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
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The antidiabetic activities of vanadium(V)
and -(IV) prodrugs are determined by their ability to release active
species upon interactions with components of biological media. The
first X-ray absorption spectroscopic study of the reactivity of typical
vanadium (V) antidiabetics, vanadate ([VVO4]3–, A) and a vanadium(IV) bis(maltolato)
complex (B), with mammalian cell cultures has been performed
using HepG2 (human hepatoma), A549 (human lung carcinoma), and 3T3-L1
(mouse adipocytes and preadipocytes) cell lines, as well as the corresponding
cell culture media. X-ray absorption near-edge structure data were
analyzed using empirical correlations with a library of model vanadium(V),
-(IV), and -(III) complexes. Both A and B ([V] = 1.0 mM) gradually converged into similar mixtures of predominantly
five- and six-coordinate VV species (∼75% total
V) in a cell culture medium within 24 h at 310 K. Speciation of V
in intact HepG2 cells also changed with the incubation time (from
∼20% to ∼70% VIV of total V), but it was
largely independent of the prodrug used (A or B) or of the predominant V oxidation state in the medium. Subcellular
fractionation of A549 cells suggested that VV reduction
to VIV occurred predominantly in the cytoplasm, while accumulation
of VV in the nucleus was likely to have been facilitated
by noncovalent bonding to histone proteins. The nuclear VV is likely to modulate the transcription process and to be ultimately
related to cell death at high concentrations of V, which may be important
in anticancer activities. Mature 3T3-L1 adipocytes (unlike for preadipocytes)
showed a higher propensity to form VIV species, despite
the prevalence of VV in the medium. The distinct V biochemistry
in these cells is consistent with their crucial role in insulin-dependent
glucose and fat metabolism and may also point to an endogenous role
of V in adipocytes. The first detailed
speciation study of typical antidiabetic vanadium(V/IV) complexes
in mammalian cell culture systems showed that the complexes decomposed
rapidly in cell culture media and were further metabolized by the
cells, which included interconversions of VV and VIV species.
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Affiliation(s)
- Aviva Levina
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Andrew I McLeod
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Anna Pulte
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Jade B Aitken
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Peter A Lay
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
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14
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Rubino FM. Toxicity of Glutathione-Binding Metals: A Review of Targets and Mechanisms. TOXICS 2015; 3:20-62. [PMID: 29056650 PMCID: PMC5634692 DOI: 10.3390/toxics3010020] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 09/04/2014] [Accepted: 01/14/2015] [Indexed: 02/07/2023]
Abstract
Mercury, cadmium, arsenic and lead are among priority metals for toxicological studies due to the frequent human exposure and to the significant burden of disease following acute and chronic intoxication. Among their common characteristics is chemical affinity to proteins and non-protein thiols and their ability to generate cellular oxidative stress by the best-known Fenton mechanism. Their health effects are however diverse: kidney and liver damage, cancer at specific sites, irreversible neurological damages with metal-specific features. Mechanisms for the induction of oxidative stress by interaction with the cell thiolome will be presented, based on literature evidence and of experimental findings.
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Affiliation(s)
- Federico Maria Rubino
- LaTMA Laboratory for Analytical Toxicology and Metabonomics, Department of Health Sciences, Università degli Studi di Milano at "Ospedale San Paolo" v. A. di Rudinì 8, I-20142 Milano, Italy.
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15
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Bresson C, Spezia R, Solari PL, Jankowski CK, Den Auwer C. XAS examination of glutathione–cobalt complexes in solution. J Inorg Biochem 2015; 142:126-31. [DOI: 10.1016/j.jinorgbio.2014.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 10/17/2014] [Accepted: 10/17/2014] [Indexed: 01/09/2023]
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16
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Zhang WH, Sui CX, Wang X, Yin GJ, Liu YF, Zhang D. Characterization of Cr(V)-induced genotoxicity using CdTe nanocrystals as fluorescent probes. Analyst 2014; 139:6357-60. [PMID: 25343163 DOI: 10.1039/c4an01698j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
CdTe nanocrystals capped by cysteamine were synthesized to study Cr(V)-induced genotoxicity. On the surface of TiO2 thin films, the stepwise process of DNA breakage induced by Cr(V)-GSH complexes was vividly observed by using CdTe-DNA self-assembled fluorescent probes; in acetate buffer solution, an analytical method was developed to detect Cr(V)-induced genotoxicity with CdTe fluorescent probes.
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Affiliation(s)
- Wen-Hao Zhang
- Henan Provincial Center for Disease Control and Prevention, Henan, Zhengzhou, 450003, People's Republic of China.
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17
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Pham THN, Aitken JB, Levina A, Lay PA. Solid-State Structural Studies of Chromium(III) Nicotinato Nutritional Supplements. Inorg Chem 2014; 53:10685-94. [DOI: 10.1021/ic501818w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- T. H. Nguyen Pham
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Jade B. Aitken
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
- Australian Synchrotron, Clayton, Victoria 3168, Australia
- Institute of Materials Structure Science, KEK, Tsukuba, Ibaraki 305-0801, Japan
| | - Aviva Levina
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Peter A. Lay
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
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18
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Bertoni FA, Bellú SE, González JC, Sala LF. Reduction of hypervalent chromium in acidic media by alginic acid. Carbohydr Polym 2014; 114:1-11. [PMID: 25263857 DOI: 10.1016/j.carbpol.2014.07.065] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 07/23/2014] [Accepted: 07/31/2014] [Indexed: 10/24/2022]
Abstract
Selective oxidation of carboxylate groups present in alginic acid by Cr(VI) affords CO2, oxidized alginic acid, and Cr(III) as final products. The redox reaction afforded first-order kinetics in [alginic acid], [Cr(VI)], and [H(+)], at fixed ionic strength and temperature. Kinetic studies showed that the redox reaction proceeds through a mechanism which combines Cr(VI)→Cr(IV)→Cr(II) and Cr(VI)→Cr(IV)→Cr(III) pathways. The mechanism was supported by the observation of free radicals, CrO2(2+) and Cr(V) as reaction intermediates. The reduction of Cr(IV) and Cr(V) by alginic acid was independently studied and it was found to occur more than 10(3) times faster than alginic acid/Cr(VI) reaction, in acid media. At pH 1-3, oxo-chromate(V)-alginic acid species remain in solution during several hours at 15°C. The results showed that this abundant structural polysaccharide present on brown seaweeds is able to reduce Cr(VI/V/IV) or stabilize high-valent chromium depending on pH value.
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Affiliation(s)
- Fernando A Bertoni
- Área Química General, Departamento de Químico-Física, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Santa Fe, Argentina; Instituto de Química de Rosario-CONICET, Suipacha 570, S2002LRK Rosario, Santa Fe, Argentina
| | - Sebastian E Bellú
- Área Química General, Departamento de Químico-Física, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Santa Fe, Argentina; Instituto de Química de Rosario-CONICET, Suipacha 570, S2002LRK Rosario, Santa Fe, Argentina.
| | - Juan C González
- Área Química General, Departamento de Químico-Física, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Santa Fe, Argentina; Instituto de Química de Rosario-CONICET, Suipacha 570, S2002LRK Rosario, Santa Fe, Argentina
| | - Luis F Sala
- Área Química General, Departamento de Químico-Física, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Santa Fe, Argentina; Instituto de Química de Rosario-CONICET, Suipacha 570, S2002LRK Rosario, Santa Fe, Argentina
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19
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Abstract
Chromium is ubiquitous in the environment as Cr(III) and Cr(VI) oxidation states, which interconvert under environmentally and biologically relevant conditions (although Cr(III) usually predominates). While Cr(VI) is an established human carcinogen and a major occupational and environmental hazard, Cr(III) has long been regarded as an essential human micronutrient, although recent literature has cast serious doubts on the validity of this postulate. Despite five decades of research, no functional Cr-containing enzymes or cofactors have been characterized conclusively, and several hypotheses on their possible structures have been refuted. Gastrointestinal absorption pathways for both Cr(III) and Cr(VI) are apparent and whole-blood speciation can involve Cr(VI) uptake and reduction by red blood cells, as well as Cr(III) binding to both proteins and low-molecular-mass ligands in the plasma. DNA-damaging effects of Cr(VI) and anti-diabetic activities of Cr(III) are likely to arise from common mechanistic pathways that involve reactive Cr(VI/V/IV) intermediates and kinetically inert Cr(III)-protein and Cr(III)-DNA adducts. Both Cr(III) and Cr(VI) are toxic to plants and microorganisms, particularly Cr(VI) due to its higher bioavailability and redox chemistry. Some bacteria reduce Cr(VI) to Cr(III) without the formation of toxic Cr(V) intermediates and these bacteria are being considered for use in the bioremediation of Cr(VI)-polluted environments.
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Affiliation(s)
- Peter A. Lay
- School of Chemistry, The University of Sydney Sydney NSW 2006 Australia
| | - Aviva Levina
- School of Chemistry, The University of Sydney Sydney NSW 2006 Australia
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20
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DeLoughery Z, Luczak MW, Zhitkovich A. Monitoring Cr intermediates and reactive oxygen species with fluorescent probes during chromate reduction. Chem Res Toxicol 2014; 27:843-51. [PMID: 24646070 PMCID: PMC4027954 DOI: 10.1021/tx500028x] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
![]()
Cr(VI)
genotoxicity is caused by products of its reductive metabolism
inside the cells. Reactive oxygen species (ROS) and Cr(V,IV) intermediates
are potential sources of oxidative damage by Cr(VI). Here, we investigated
seven fluorescent probes for the detection of ROS and non-ROS oxidants
in Cr(VI) reactions with its main reducers. We found that Cr(V)-skipping
metabolism of Cr(VI) by ascorbate in vitro gave no
responses with all tested dyes, indicating nonreactivity of Cr(IV)
and absence of ROS. Cr(VI) reduction with glutathione (GSH) or Cys
strongly enhanced the fluorescence of dichlorofluorescein (DCF) and
dihydrorhodamine 123 (DHR123) but produced minimal fluorescence with
dihydroethidium and no increases with aminophenylfluorescein and CellRox
Green, Orange, and Red. Several tests showed that Cr(VI)-thiol reactions
lacked ROS and that Cr(V) caused oxidation of DCF and DHR123. DCF
reacted only with free Cr(V), whereas DHR123 detected both the free
Cr(V) and Cr(V)-GSH complex. We estimated that Cr(VI)-GSH reactions
generated approximately 75% Cr(V)-GSH and 25% free Cr(V), whereas
Cys reactions appeared to produce only free Cr(V). DHR123 measurements
in H460 cells showed that reduction of Cr(VI) was complete within
20 min postexposure, but it lasted at least 1 h without GSH. Cells
with restored ascorbate levels exhibited no DCF or DHR123 oxidation
by Cr(VI). Overall, our results demonstrated that Cr(VI) metabolism
with its biological reducers lacked ROS and that DHR123 and DCF responses
were indicators of total and free Cr(V), respectively. CellRox dyes,
dihydroethidium and aminophenylfluorescein, are insensitive to Cr(V,IV)
and can be used for monitoring ROS during coexposure to Cr(VI) and
oxidants.
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Affiliation(s)
- Zachary DeLoughery
- Department of Pathology and Laboratory Medicine, Brown University , 70 Ship Street, Providence, Rhode Island 02912, United States
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21
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Morse JL, Luczak MW, Zhitkovich A. Chromium(VI) causes interstrand DNA cross-linking in vitro but shows no hypersensitivity in cross-link repair-deficient human cells. Chem Res Toxicol 2013; 26:1591-8. [PMID: 24059640 DOI: 10.1021/tx400293s] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Hexavalent chromium is a human carcinogen activated primarily by direct reduction with cellular ascorbate and to a lesser extent, by glutathione. Cr(III), the final product of Cr(VI) reduction, forms six bonds allowing intermolecular cross-linking. In this work, we investigated the ability of Cr(VI) to cause interstrand DNA cross-links (ICLs) whose formation mechanisms and presence in human cells are currently uncertain. We found that in vitro reduction of Cr(VI) with glutathione showed a sublinear production of ICLs, the yield of which was less than 1% of total Cr-DNA adducts at the optimal conditions. Formation of ICLs in fast ascorbate-Cr(VI) reactions occurred during a short reduction interval and displayed a linear dose dependence with the average yield of 1.3% of total adducts. In vitro production of ICLs was strongly suppressed by increasing buffer molarity, indicating inhibitory effects of ligand-Cr(III) binding on the formation of cross-linking species. The presence of ICLs in human cells was assessed from the impact of ICL repair deficiencies on Cr(VI) responses. We found that ascorbate-restored FANCD2-null and isogenic FANCD2-complemented cells showed similar cell cycle inhibition and toxicity by Cr(VI). XPA-null cells are defective in the repair of Cr-DNA monoadducts, but stable knockdowns of ERCC1 or XPF in these cells with extended time for the completion of cross-linking reactions did not produce any sensitization to Cr(VI). Our results together with chemical and steric considerations of Cr(III) reactivity suggest that ICL generation by chromate is probably an in vitro phenomenon occurring at conditions permitting the formation of Cr(III) oligomers.
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Affiliation(s)
- Jessica L Morse
- Department of Pathology and Laboratory Medicine, Brown University , 70 Ship Street, Providence, Rhode Island 02912, United States
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22
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Bartholomäus R, Irwin JA, Shi L, Smith SM, Levina A, Lay PA. Isolation, Characterization, and Nuclease Activity of Biologically Relevant Chromium(V) Complexes with Monosaccharides and Model Diols. Likely Intermediates in Chromium-Induced Cancers. Inorg Chem 2013; 52:4282-92. [DOI: 10.1021/ic3022408] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ruben Bartholomäus
- Fachbereich Chemie, Philipps-Universität Marburg,
Hans-Meerwein-Strasse, D-35032 Marburg, Germany
- School of Chemistry, The University of Sydney, New South
Wales 2006, Australia
| | - Jennifer A. Irwin
- School of Chemistry, The University of Sydney, New South
Wales 2006, Australia
| | - Liwei Shi
- School of Chemistry, The University of Sydney, New South
Wales 2006, Australia
| | - Siwaporn Meejoo Smith
- School of Chemistry, The University of Sydney, New South
Wales 2006, Australia
- Department of Chemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand
| | - Aviva Levina
- School of Chemistry, The University of Sydney, New South
Wales 2006, Australia
| | - Peter A. Lay
- School of Chemistry, The University of Sydney, New South
Wales 2006, Australia
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23
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Kaufman SH, Weber JM. Spectroscopy and Photochemistry of Sodium Chromate Ester Cluster Ions. J Phys Chem A 2013; 117:2144-51. [DOI: 10.1021/jp309380v] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Sydney H. Kaufman
- JILA and Department of Chemistry
and Biochemistry, University of Colorado at Boulder, Boulder, Colorado
80309-0440, United States
| | - J. Mathias Weber
- JILA and Department of Chemistry
and Biochemistry, University of Colorado at Boulder, Boulder, Colorado
80309-0440, United States
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24
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Pacheco M, Santos MA, Pereira P, Martínez JI, Alonso PJ, Soares MJ, Lopes JC. EPR detection of paramagnetic chromium in liver of fish (Anguilla anguilla) treated with dichromate(VI) and associated oxidative stress responses-contribution to elucidation of toxicity mechanisms. Comp Biochem Physiol C Toxicol Pharmacol 2013; 157:132-40. [PMID: 23142145 DOI: 10.1016/j.cbpc.2012.10.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 10/29/2012] [Accepted: 10/30/2012] [Indexed: 11/20/2022]
Abstract
The impact of chromium (Cr) on fish health has been the subject of numerous investigations, establishing a wide spectrum of toxicity, attributed particularly to the hexavalent form [Cr(VI)]. However, reports on the simultaneous assessment of Cr toxicity in fish and its toxico-kinetics, namely involving metal speciation, are scarce. Therefore, keeping in view the understanding of the mechanisms of Cr(VI) toxicity, this work intended to detect the formation of paramagnetic Cr species in liver of Anguilla anguilla following short-term dichromate(VI) intraperitoneal treatment (up to 180 min), assessing simultaneously the pro-oxidant properties. The formation of Cr(V) and Cr(III) was examined by electron paramagnetic resonance (EPR), as an innovative approach in the context of fish toxicology, and related with the levels of total Cr. Cr(V) was successfully detected and quantified by EPR spectrometry, showing a transient occurrence, mostly between 15 and 90 min post-injection, with a peak at 30 min. The limitations of EPR methodology towards the detection and quantification of Cr(III) were confirmed. Although Cr(VI) exposure induced the antioxidant system in the eel's liver, the oxidative deterioration of lipids was not prevented. Overall, the results suggested that Cr(V), as a short-lived species, did not appear to be directly and primarily responsible for the cellular damaging effects observed, since stress responses persisted up to the end of exposure regardless Cr(V) drastic decay. Though further research is needed, ROS mediated pathways (suggested by superoxide dismutase and catalase activity induction) and formation of Cr(III) complexes emerged as the most plausible mechanisms involved in Cr(VI) toxicity.
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Affiliation(s)
- M Pacheco
- Biology Department of the University of Aveiro & CESAM, 3810-193 Aveiro, Portugal.
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25
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Facile preparation of glutathione-stabilized gold nanoclusters for selective determination of chromium (III) and chromium (VI) in environmental water samples. Anal Chim Acta 2013; 770:140-6. [PMID: 23498696 DOI: 10.1016/j.aca.2013.01.042] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 01/14/2013] [Accepted: 01/20/2013] [Indexed: 11/22/2022]
Abstract
A novel method for selective determination of Cr(III) and Cr(VI) in environmental water samples was developed based on target-induced fluorescence quenching of glutathione-stabilized gold nanoclusters (GSH-Au NCs). Fluorescent GSH-Au NCs were synthesized by a one-step approach employing GSH as reducing/protecting reagent. It was found that Cr(III) and Cr(VI) showed pH-dependent fluorescence quenching capabilities for GSH-Au NCs, and thus selective determination of Cr(III) and Cr(VI) could be achieved at different pHs. Addition of EDTA was able to effectively eliminate the interferences from other metal ions, leading to a good selectivity for this method. Under optimized conditions, Cr(III) showed a linear range of 25-3800 μg L(-1) and a limit of detection (LOD) of 2.5 μg L(-1). The Cr(VI) ion demonstrated a linear range of 5-500 μg L(-1) and LOD of 0.5 μg L(-1). The run-to-run relative standard deviations (n=5) for Cr(III) and Cr(VI) were 3.9% and 2.8%, respectively. The recoveries of Cr(III) and Cr(VI) in environmental water samples were also satisfactory (76.3-116%). This method, with its simplicity, low cost, high selectivity and sensitivity, could be used as a promising tool for chromium analysis in environmental water samples.
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26
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Abstract
Drinking water supplies in many geographic areas contain chromium in the +3 and +6 oxidation states. Public health concerns are centered on the presence of hexavalent Cr that is classified as a known human carcinogen via inhalation. Cr(VI) has high environmental mobility and can originate from anthropogenic and natural sources. Acidic environments with high organic content promote the reduction of Cr(VI) to nontoxic Cr(III). The opposite process of Cr(VI) formation from Cr(III) also occurs, particularly in the presence of common minerals containing Mn(IV) oxides. Limited epidemiological evidence for Cr(VI) ingestion is suggestive of elevated risks for stomach cancers. Exposure of animals to Cr(VI) in drinking water induced tumors in the alimentary tract, with linear and supralinear responses in the mouse small intestine. Chromate, the predominant form of Cr(VI) at neutral pH, is taken up by all cells through sulfate channels and is activated nonenzymatically by ubiquitously present ascorbate and small thiols. The most abundant form of DNA damage induced by Cr(VI) is Cr-DNA adducts, which cause mutations and chromosomal breaks. Emerging evidence points to two-way interactions between DNA damage and epigenetic changes that collectively determine the spectrum of genomic rearrangements and profiles of gene expression in tumors. Extensive formation of DNA adducts, clear positivity in genotoxicity assays with high predictive values for carcinogenicity, the shape of tumor-dose responses in mice, and a biological signature of mutagenic carcinogens (multispecies, multisite, and trans-sex tumorigenic potency) strongly support the importance of the DNA-reactive mutagenic mechanisms in carcinogenic effects of Cr(VI). Bioavailability results and kinetic considerations suggest that 10-20% of ingested low-dose Cr(VI) escapes human gastric inactivation. The directly mutagenic mode of action and the incompleteness of gastric detoxification argue against a threshold in low-dose extrapolation of cancer risk for ingested Cr(VI).
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Affiliation(s)
- Anatoly Zhitkovich
- Department of Pathology and Laboratory Medicine, Brown University, 70 Ship Street, Providence, RI 02912, United States.
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27
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Levina A, Zhang L, Lay PA. Formation and reactivity of chromium(V)-thiolato complexes: a model for the intracellular reactions of carcinogenic chromium(VI) with biological thiols. J Am Chem Soc 2010; 132:8720-31. [PMID: 20527748 DOI: 10.1021/ja101675w] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The nature of the long-lived EPR-active Cr(V) species observed in cells and biological fluids exposed to carcinogenic Cr(VI) has been definitively assigned from detailed kinetic and spectroscopic analyses of a model reaction of Cr(VI) with p-bromobenzenethiol (RSH) in the presence or absence of cyclic 1,2-diols (LH(2)) in aprotic or mixed solvents. The first definitive structures for Cr(V) complexes with a monodentate thiolato ligand, [Cr(V)O(SR)(4)](-) (g(iso) = 1.9960, A(iso) = 14.7 x 10(-4) cm(-1)), [Cr(V)OL(SR)(2)](-) (g(iso) = 1.9854, A(iso) = (15.8-16.2) x 10(-4) cm(-1)) and [Cr(V)(O)(2)(SR)(2)](-) (g(iso) = 1.9828, A(iso) = 6.8 x 10(-4) cm(-1)) were assigned by EPR spectroscopy and electrospray mass spectrometry. The unusually low A(iso) ((53)Cr) value for the latter species is consistent with its rare four-coordinate, bis-oxido structure. The [Cr(V)OL(SR)(2)](-) species are responsible for the transient g(iso) approximately 1.986 EPR signals observed in living cells and animals treated with Cr(VI) (where RSH and LH(2) are biological thiols and 1,2-diols, respectively). For the first time, concentrations of Cr(V) intermediates formed during the reduction of Cr(VI) were determined by quantitative EPR spectroscopy, and a detailed reaction mechanism was proposed on the basis of stochastic simulations of the kinetic curves for Cr(V) species. A key feature of the proposed mechanism is the regeneration of Cr(V) species in the presence of Cr(VI) through the formation of organic free radicals, followed by the rapid reactions of the formed radicals with Cr(VI). The concentration of Cr(V) grows rapidly at the beginning of the reaction, reaches a steady-state level, and then drops sharply once Cr(VI) is spent. Similar mechanisms are likely to operate during the reduction of Cr(VI) in biological environment rich in reactive C-H bonds, including the oxidative DNA damage by Cr(V) intermediates.
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Affiliation(s)
- Aviva Levina
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
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28
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Finney L, Chishti Y, Khare T, Giometti C, Levina A, Lay PA, Vogt S. Imaging metals in proteins by combining electrophoresis with rapid x-ray fluorescence mapping. ACS Chem Biol 2010; 5:577-87. [PMID: 20392082 DOI: 10.1021/cb1000263] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Growing evidence points toward a very dynamic role for metals in biology. This suggests that physiological circumstance may mandate metal ion redistribution among ligands. This work addresses a critical need for technology that detects, identifies, and measures the metal-containing components of complex biological matrixes. We describe a direct, user-friendly approach for identifying and quantifying metal-protein adducts in complex samples using native- or SDS-PAGE, blotting, and rapid synchrotron X-ray fluorescence mapping with micro-XANES (X-ray absorption near-edge structure) of entire blots. The identification and quantification of each metal bound to a protein spot has been demonstrated, and the technique has been applied in two exemplary cases. In the first, the speciation of the in vitro binding of exogenous chromium to blood serum proteins was influenced markedly by both the oxidation state of chromium exposed to the serum proteins and the treatment conditions, which is of relevance to the biochemistry of Cr dietary supplements. In the second case, in vivo changes in endogenous metal speciation were examined to probe the influence of oxygen depletion on iron speciation in Shewanella oneidensis.
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Affiliation(s)
- Lydia Finney
- Biosciences Division and
- X-ray Sciences Division, Argonne National Laboratory, Argonne, Illinois
| | | | | | | | - Aviva Levina
- School of Chemistry, The University of Sydney, NSW 2006, Australia
| | - Peter A Lay
- School of Chemistry, The University of Sydney, NSW 2006, Australia
| | - Stefan Vogt
- X-ray Sciences Division, Argonne National Laboratory, Argonne, Illinois
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29
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Benedito FL, Petrenko T, Bill E, Weyhermüller T, Wieghardt K. Square Planar Bis{3,6-bis(trimethylsilyl)benzene-1,2-dithiolato}metal Complexes of CrII, CoIII, and RhII: An Experimental and Density Functional Theoretical Study. Inorg Chem 2009; 48:10913-25. [DOI: 10.1021/ic9008976] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Flávio Luiz Benedito
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Taras Petrenko
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Eckhard Bill
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Thomas Weyhermüller
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Karl Wieghardt
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
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30
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31
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Yang XD, Zhang QQ, Chen RF, Shen RF. Speciation of aluminum(III) complexes with oxidized glutathione in acidic aqueous solutions. ANAL SCI 2008; 24:1005-12. [PMID: 18689941 DOI: 10.2116/analsci.24.1005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The structural speciation aspects, including the binding sites, species, complexation abilities and effects of the oxidized glutathione (GSSG) with aluminum(III) in aqueous solutions, have been studied by means of many analytical techniques: pH-potentiometry (25 degrees C, 0.1 M KCl and 37 degrees C, 0.15 M NaCl medium) was used to characterize the stoichiometry and stability of the species formed in the interactions of the Al(III) ion and the peptide GSSG, while multinuclear ((1)H, (13)C, (27)Al) nuclear magnetic resonance (NMR) and electrospray mass spectroscopy (ESI-MS) were applied to characterize the binding sites and species of the metal ion in the complexes. Two-dimensional ((1)H, (1)H-NOESY) was also employed to reveal the difference in the conformational behavior of the peptide and its complexes. The following results were obtained: (1) Aluminum(III) can coordinate with the important biomolecule GSSG through the following binding sites: glycyl and glutamyl carboxyl groups to form various mononuclear 1:1 (AlLH(4), AlLH(3), AlLH(2), AlLH, AlL, AlLH(-1), AlLH(-2)) and several binuclear 2:1 (Al(2)LH(4), Al(2)LH(2), Al(2)L) species (where H(6)L(2+) denotes the totally protonated oxidized glutathione) in acidic aqueous solutions. (2) It indicates that the COO(-) groups at low level of preorganization in such small peptide are not sufficient to keep the Al(III) ion in solution and to prevent the precipitation of Al(OH)(3) in the physiological pH range. (3) It also suggests that the occurrence of an Al-linked complexation, the conformation of the peptide GSSG in aqueous solutions appeared to change a little, relative to the initial structure.
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Affiliation(s)
- Xiao Di Yang
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, P. R. China
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High selectivity for l-cysteine residue at axial solvated site of trigonal–bipyramidal palladium(II) complex with tripodal tetradentate phosphine. J Organomet Chem 2008. [DOI: 10.1016/j.jorganchem.2008.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Raghunathan VK, Tettey JN, Grant MH. Uptake of Cr (VI) and Cr (III)–GSH complex across rat liver cell nuclei. Toxicology 2008. [DOI: 10.1016/j.tox.2008.07.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Borthiry GR, Antholine WE, Myers JM, Myers CR. Addition of DNA to Cr(VI) and cytochrome b5 containing proteoliposomes leads to generation of DNA strand breaks and Cr(III) complexes. Chem Biodivers 2008; 5:1545-1557. [PMID: 18729091 PMCID: PMC2715337 DOI: 10.1002/cbdv.200890143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Chromium (Cr) is a cytotoxic metal that can be associated with a variety of types of DNA damage, including Cr-DNA adducts and strand breaks. Prior studies with purified human cytochrome b(5) and NADPH:P450 reductase in reconstituted proteoliposomes (PLs) demonstrated rapid reduction of Cr(VI) (hexavalent chromium, as CrO(4)(2-), and the generation of Cr(V), superoxide (O(2)(*-)), and hydroxyl radical (HO(*)). Studies reported here examined the potential for the species produced by this system to interact with DNA. Strand breaks of purified plasmid DNA increased over time aerobically, but were not observed in the absence of O(2). Cr(V) is formed under both conditions, so the breaks are not mediated directly by Cr(V). The aerobic strand breaks were significantly prevented by catalase and EtOH, but not by the metal chelator diethylenetriaminepentaacetic acid (DTPA), suggesting that they are largely due to HO(*) from Cr-mediated redox cycling. EPR was used to assess the formation of Cr-DNA complexes. Following a 10-min incubation of PLs, CrO(4)(2-), and plasmid DNA, intense EPR signals at g=5.7 and g=5.0 were observed. These signals are attributed to specific Cr(III) complexes with large zero field splitting (ZFS). Without DNA, the signals in the g=5 region were weak. The large ZFS signals were not seen, when Cr(III)Cl(3) was incubated with DNA, suggesting that the Cr(III)-DNA interactions are different when generated by the PLs. After 24 h, a broad signal at g=2 is attributed to Cr(III) complexes with a small ZFS. This g=2 signal was observed without DNA, but it was different from that seen with plasmid. It is concluded that EPR can detect specific Cr(III) complexes that depend on the presence of plasmid DNA and the manner in which the Cr(III) is formed.
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Affiliation(s)
- Griselda R. Borthiry
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - William E. Antholine
- Department of Biophysics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Judith M. Myers
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Charles R. Myers
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
- Free Radical Research Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
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Borthiry GR, Antholine WE, Myers JM, Myers CR. Reductive activation of hexavalent chromium by human lung epithelial cells: generation of Cr(V) and Cr(V)-thiol species. J Inorg Biochem 2008; 102:1449-62. [PMID: 18279960 PMCID: PMC2497427 DOI: 10.1016/j.jinorgbio.2007.12.030] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 11/26/2007] [Accepted: 12/21/2007] [Indexed: 11/25/2022]
Abstract
Chromium(VI) compounds (e.g. chromates) are cytotoxic, mutagenic, and potentially carcinogenic. The reduction of Cr(VI) can yield reactive intermediates such as Cr(V) and reactive oxygen species. Bronchial epithelial cells are the primary site of pulmonary exposure to inhaled Cr(VI) and are the primary cells from which Cr(VI)-associated human cancers arise. BEAS-2B cells were used here as a model of normal human bronchial epithelium for studies on the reductive activation of Cr(VI). Cells incubated with Na(2)CrO(4) exhibited two Cr(V) ESR signals, g=1.979 and 1.985, which persisted for at least 1h. The g=1.979 signal is similar to that generated in vitro by human microsomes and by proteoliposomes containing P450 reductase and cytochrome b(5). Unlike many cells in culture, these cells continued to express P450 reductase and cytochrome b(5). Studies with the non-selective thiol oxidant diamide indicated that the g=1.985 signal was thiol-dependent whereas the g=1.979 signal was not. Pretreatment with phenazine methosulfate eliminated both Cr(V) signals suggesting that Cr(V) generation is largely NAD(P)H-dependent. ESR spectra indicated that a portion of the Cr(VI) was rapidly reduced to Cr(III). Cells incubated with an insoluble chromate, ZnCrO(4), also generated both Cr(V) signals, whereas Cr(V) was not detected with insoluble PbCrO(4). In clonogenic assays, the cells were very sensitive to Na(2)CrO(4) and ZnCrO(4), but considerably less sensitive to PbCrO(4).
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Affiliation(s)
- Griselda R. Borthiry
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - William E. Antholine
- Department of Biophysics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Judith M. Myers
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Charles R. Myers
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
- Free Radical Research Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
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Salnikow K, Zhitkovich A. Genetic and epigenetic mechanisms in metal carcinogenesis and cocarcinogenesis: nickel, arsenic, and chromium. Chem Res Toxicol 2008; 21:28-44. [PMID: 17970581 PMCID: PMC2602826 DOI: 10.1021/tx700198a] [Citation(s) in RCA: 561] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Chronic exposure to nickel(II), chromium(VI), or inorganic arsenic (iAs) has long been known to increase cancer incidence among affected individuals. Recent epidemiological studies have found that carcinogenic risks associated with chromate and iAs exposures were substantially higher than previously thought, which led to major revisions of the federal standards regulating ambient and drinking water levels. Genotoxic effects of Cr(VI) and iAs are strongly influenced by their intracellular metabolism, which creates several reactive intermediates and byproducts. Toxic metals are capable of potent and surprisingly selective activation of stress-signaling pathways, which are known to contribute to the development of human cancers. Depending on the metal, ascorbate (vitamin C) has been found to act either as a strong enhancer or suppressor of toxic responses in human cells. In addition to genetic damage via both oxidative and nonoxidative (DNA adducts) mechanisms, metals can also cause significant changes in DNA methylation and histone modifications, leading to epigenetic silencing or reactivation of gene expression. In vitro genotoxicity experiments and recent animal carcinogenicity studies provided strong support for the idea that metals can act as cocarcinogens in combination with nonmetal carcinogens. Cocarcinogenic and comutagenic effects of metals are likely to stem from their ability to interfere with DNA repair processes. Overall, metal carcinogenesis appears to require the formation of specific metal complexes, chromosomal damage, and activation of signal transduction pathways promoting survival and expansion of genetically/epigenetically altered cells.
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Affiliation(s)
- Konstantin Salnikow
- Konstantin Salnikow, National Cancer Institute, Bldg. 538, Room 205 E, Frederick, MD 21702, Phone: 301-846-5623, Fax: 301-846-5946, E-mail:
| | - Anatoly Zhitkovich
- Anatoly Zhitkovich, Brown University, Center for Genomics and Proteomics, Department of Pathology and Laboratory Medicine, 70 Ship Street, Providence RI 02912, Phone: 401-863-2912, Fax: 401-863-9008, E-mail:
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Patel S, Mishra B. Chromium(VI) oxidants having quaternary ammonium ions: studies on synthetic applications and oxidation kinetics. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.02.073] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Venkataramanan NS, Rajagopal S, Vairamani M. Oxidation of methionines by oxochromium(V) cations: A kinetic and spectral study. J Inorg Biochem 2007; 101:274-82. [PMID: 17098287 DOI: 10.1016/j.jinorgbio.2006.09.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2006] [Revised: 09/26/2006] [Accepted: 09/28/2006] [Indexed: 11/20/2022]
Abstract
The oxidation of methionine (Met) plays an important role during biological conditions of oxidative stress as well as for protein stability. By choosing [oxo(salen)chromium(V)] ions, [(salen)Cr(V)=O](+) (where salen = bis(salicylidene)ethylenediamine) as suitable biomimics for the peptide complexes that are formed during the reduction of Cr(VI) with biological reductants, the oxidation of methionine and substituted methionines with five [oxo(salen)chromium(V)] complexes in aqueous acetonitrile has been investigated by spectrophotometric, electron paramagnetic resonance (EPR) spectroscopy and electrospray ionization mass spectrometry (ESI-MS) methods. In aqueous solution [(salen)Cr(V)=O](+) ion is short lived, ligation of H(2)O to the Cr center takes place and [O=Cr(V)(salen)-H(2)O](+) adduct is the active oxidant. The reaction is found to be first order each in the oxidant and the substrate. The presence of water in the reaction system accelerates the reaction rate and an inactive, stable mu-oxo dimer is also formed during the course of the reaction. On the basis of spectral, kinetic and product analysis study a mechanism involving direct oxygen transfer from [O=Cr(V)(salen)-H(2)O](+) to methionine has been proposed as a suitable mechanism for the reaction.
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Chaudhary S, Van Horn JD. Biphasic kinetics in the reaction between amino acids or glutathione and the chromium acetate cluster, [Cr3O(OAc)6]+. Mutat Res 2006; 610:56-65. [PMID: 16890480 DOI: 10.1016/j.mrgentox.2006.06.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/05/2006] [Indexed: 11/20/2022]
Abstract
Kinetics for the breakdown of the trinuclear chromium acetate cluster with a series of monoprotic and diprotic amino acid ligands and with glutathione in aqueous media have been investigated spectrophotometrically at pH 3.5-5.5 and in a temperature range of 45-60 degrees C. Under pseudo-first-order conditions, reactions with these ligands exhibited biphasic kinetic behavior that can be accounted for by a consecutive two-step reaction, A-->B-->C, where A is assumed to be a forced ion pair, B an intermediate and C is the product; experimental data fit to a biexponential equation for the transformation. Rates for k(short), k(long), and k(obs) were determined by manual extrapolation of absorbance data or curve-fitting routines; associated activation parameters for each step of the reaction were calculated using the Eyring equation. Rates for the first and second steps of the reaction are on the order of approximately 10(-4) and approximately 10(-5)s(-1), respectively. The large negative values of DeltaS++ and smaller DeltaH++ in the first step indicate an associative step, while high positive values of DeltaS(double dagger) in the second step indicate dissociation. To account for the results mechanistically, the results are interpreted to be a first step of ligand exchange with a pseudo-axial aqua ligand, followed by a dissociative step involving acetate or oxo ligand displacement. The dissociative step is the rate determining step, with k(obs) approximately k(long). The results demonstrate reaction pathways that are available to the Cr(III) metal centers that may be physiologically relevant in the ligand-rich environment of biological systems. Under general conditions Cr(III) clusters may be expected to be broken down, unless some unique biological environment stabilizes the cluster. The present study has application to the processes related to Cr(III) transport and excretion, to potential mechanisms of Cr(III) action in a biological setting, and to the pharmacokinetics of Cr(III) supplements for animal and human consumption.
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Affiliation(s)
- Shveta Chaudhary
- University of Missouri-Kansas City, Department of Chemistry, 5110 Rockhill Road, Kansas City, MO 64110-2446, USA
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Chromium(V) complexes generated in Arthrobacter oxydans by simulation analysis of EPR spectra. J Inorg Biochem 2006; 100:1827-33. [DOI: 10.1016/j.jinorgbio.2006.07.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2006] [Revised: 07/13/2006] [Accepted: 07/13/2006] [Indexed: 11/23/2022]
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Di Marco VB, Bombi GG. Electrospray mass spectrometry (ESI-MS) in the study of metal-ligand solution equilibria. MASS SPECTROMETRY REVIEWS 2006; 25:347-79. [PMID: 16369936 DOI: 10.1002/mas.20070] [Citation(s) in RCA: 215] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In the 20 years, since the introduction of electrospray mass spectrometry (ESI-MS), the use of this technique in various fields of inorganic, organometallic, and analytical chemistry has been steadily increasing. In this study, the application of ESI-MS to the study of metal-ligand solution equilibria is reviewed (till 2004 included). In a first section, advantages and drawbacks of ESI-MS in this type of application are described. Subsequently, a list of ca. 300 studies is reported, in which ESI-MS was used to give number and stoichiometry of the species at equilibrium, or also to estimate their stability constants. All studies are classified according to the metal ions under examination. Other related applications, such as host-guest interactions and metal ion-protein binding studies, are briefly reviewed as well.
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Kapre R, Ray K, Sylvestre I, Weyhermüller T, DeBeer George S, Neese F, Wieghardt K. Molecular and Electronic Structures of Oxo-bis(benzene-1,2-dithiolato)chromate(V) Monoanions. A Combined Experimental and Density Functional Study. Inorg Chem 2006; 45:3499-509. [PMID: 16634580 DOI: 10.1021/ic051844s] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Two oxo-bis(benzene-1,2-dithiolato)chromate(V) complexes, namely, [CrO(L(Bu))2]1- and [CrO(L(Me))2]1-, have been synthesized and studied by UV-vis, EPR, magnetic circular dichroism (MCD), and X-ray absorption spectroscopy and by X-ray crystallography; their electro- and magnetochemistries are reported. H2L(Bu) represents the pro-ligand 3,5-di-tert-butylbenzene-1,2-dithiol, and H2L(Me) is the corresponding 4-methyl-benzene-1,2-dithiol. A structural feature of interest for both the complexes is the folding of the dithiolate ligands about the S-S vector providing Cs symmetry to the complexes. Geometry optimizations using all-electron density functional theory with scalar relativistic corrections at the second-order Douglas-Kroll-Hess (DKH2) and zeroth-order regular approximation (ZORA) levels result in excellent agreement with the experimentally determined structures and electronic and S K-edge X-ray absorption spectra. From DFT calculations, the Cs instead of C2v symmetry for the complexes is attributed to the strong S(3p) --> Cr(3d(x2-y2)) pi-donation in Cs geometry providing additional stability to the complexes.
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Affiliation(s)
- Ruta Kapre
- Max-Planck Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
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Bosco Bharathy J, Ganesan T, Rajkumar E, Rajagopal S, Manimaran B, Rajendran T, Lu KL. Micellar effect on the electron transfer reaction of chromium(V) ion with organic sulfides. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.02.052] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Harris HH, Levina A, Dillon CT, Mulyani I, Lai B, Cai Z, Lay PA. Time-dependent uptake, distribution and biotransformation of chromium(VI) in individual and bulk human lung cells: application of synchrotron radiation techniques. J Biol Inorg Chem 2005; 10:105-18. [PMID: 15714299 DOI: 10.1007/s00775-004-0617-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2004] [Accepted: 11/22/2004] [Indexed: 10/25/2022]
Abstract
Chromium(VI) is a human carcinogen, primarily affecting the respiratory tract probably via active transport into cells, followed by the reduction to Cr(III) with the formation of DNA-damaging intermediates. Distribution of Cr and endogenous elements within A549 human lung adenocarcinoma epithelial cells, following treatment with Cr(VI) (100 microM, 20 min or 4 h) were studied by synchrotron-radiation-induced X-ray emission (SRIXE) of single freeze-dried cells. After the 20-min treatment, Cr was confined to a small area of the cytoplasm and strongly co-localized with S, Cl, K, and Ca. After the 4-h treatment, Cr was distributed throughout the cell, with higher concentrations in the nucleus and the cytoplasmic membrane. This time-dependence corresponded to approximately 100% or 0% clonogenic survival of the cells following the 20-min or 4-h treatments, respectively, and could potentially be explained by a new cellular protective mechanism. Such processes may also be important in reducing the potential hazards of Cr(III) dietary supplements, for which there is emerging evidence that they exert their anti-diabetic effects via biological oxidation to Cr(VI). The predominance of Cr(III) was confirmed by micro-XANES spectroscopy of intracellular Cr hotspots. X-ray absorption spectroscopy (XANES and EXAFS, using freeze-dried cells after the 0-4-h treatments) was used to gain insight into the chemical structures of Cr(III) complexes formed during the intracellular reduction of Cr(VI). The polynuclear nature of such complexes (probably with a combination of carboxylato and hydroxo bridging groups and O-donor atoms of small peptides or proteins) was established by XAFS data analyses.
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Affiliation(s)
- Hugh H Harris
- Centre for Heavy Metals Research, and Centre for Structural Biology and Structural Chemistry, School of Chemistry, University of Sydney, NSW, Australia
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Levina A, Lay PA. Mechanistic studies of relevance to the biological activities of chromium. Coord Chem Rev 2005. [DOI: 10.1016/j.ccr.2004.02.017] [Citation(s) in RCA: 156] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Levina A, Armstrong RS, Lay PA. Three-dimensional structure determination using multiple-scattering analysis of XAFS: applications to metalloproteins and coordination chemistry. Coord Chem Rev 2005. [DOI: 10.1016/j.ccr.2004.10.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Kinetics and mechanism of a macrocyclic chromium(III) complex oxidation to chromium(IV) by hexacyanoferrate(III) in strongly alkaline media. TRANSIT METAL CHEM 2004. [DOI: 10.1007/s11243-004-4991-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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49
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Gotoh T, Iguchi H, Kikuchi KI. Separation of glutathione and its related amino acids by nanofiltration. Biochem Eng J 2004. [DOI: 10.1016/j.bej.2003.12.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Codd R. Metalloglycomics: a new perspective upon competitive metal–carbohydrate binding using EPR spectroscopy. Chem Commun (Camb) 2004:2653-5. [PMID: 15568052 DOI: 10.1039/b411335g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ternary complexes formed between calcium, the oxochromium(v) ion and N-acetylneuraminic (sialic) acid (naH(6)) of the form, Ca(ii)-oxoCr(v)-naH(6), have electronic structures and equilibrium distributions distinct from the binary oxoCr(v)-naH(6) analogues, as illustrated by electron paramagnetic resonance (EPR) spectroscopy.
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Affiliation(s)
- Rachel Codd
- Centre for Heavy Metals Research, School of Chemistry, University of Sydney, NSW 2006, Australia.
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