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Gumerova NI, Rompel A. Speciation atlas of polyoxometalates in aqueous solutions. SCIENCE ADVANCES 2023; 9:eadi0814. [PMID: 37343109 DOI: 10.1126/sciadv.adi0814] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 05/15/2023] [Indexed: 06/23/2023]
Abstract
Speciation is the key parameter in solution chemistry that describes the composition, concentration, and oxidation state of each chemical form of an element present in a sample. The speciation study of complex polyatomic ions has remained challenging because of the large number of factors affecting stability and the limited number of direct methods. To address these challenges, we developed the speciation atlas of 10 polyoxometalates commonly used in catalytic and biological applications in aqueous solutions, where the speciation atlas provides both a species distribution database and a predictive model for other polyoxometalates to be used. Compiled for six different polyoxometalate archetypes with three types of addenda ions based on 1309 nuclear magnetic resonance spectra under 54 different conditions, the atlas has revealed a previously unknown behavior of polyoxometalates that may account for their potency as biological agents and catalysts. The atlas is intended to promote the interdisciplinary use of metal oxides in various scientific fields.
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Affiliation(s)
- Nadiia I Gumerova
- Universität Wien, Fakultät für Chemie, Institut für Biophysikalische Chemie, Josef-Holaubek-Platz 2, 1090 Wien, Austria
| | - Annette Rompel
- Universität Wien, Fakultät für Chemie, Institut für Biophysikalische Chemie, Josef-Holaubek-Platz 2, 1090 Wien, Austria
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Kostenkova K, Arhouma Z, Postal K, Rajan A, Kortz U, Nunes GG, Crick DC, Crans DC. Pt IV- or Mo VI-substituted decavanadates inhibit the growth of Mycobacterium smegmatis. J Inorg Biochem 2021; 217:111356. [PMID: 33582396 DOI: 10.1016/j.jinorgbio.2021.111356] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 01/07/2021] [Accepted: 01/12/2021] [Indexed: 10/22/2022]
Abstract
Inhibitory effects of two monosubstituted decavanadates by PtIV in monoplatino(IV)nonavanadate(V) ([H2PtIVV9O28]5-, V9Pt), and by MoIV in monomolybdo(VI)nonavanadate(V) ([MoVIV9O28]5-,V9Mo) were investigated against the growth of Mycobacterium smegmatis with the EC50 values of 0.0048 mM and 0.015 mM, respectively. These compare to the reported inhibitory value for decavanadate ([V10O28]6-/[HV10O28]5-, V10) on Mycobacterium smegmatis (EC50 = 0.0037 mM). Time-dependent 51V NMR spectroscopic studies were carried out for all three polyanions in aqueous solution, biological medium (7H9), heated and non-heated supernatant to evaluate their stability in their respective media, monitor their hydrolysis to form various oxovanadates over time and calculate the EC50 values. These studies allow us to calculate adjusted and maximum EC50 for the polyoxovanadate (POV) present in solution at the beginning of the study when there is most intact anion in the media and thus the EC50 values represent the initial effects of the POVs. The results have shown that V10 is 1.3 times more potent than V9Pt and 4 times more potent than V9Mo, indicating that the inhibitory effects of monosubstituted polyanions are related to the V10 structure. We attributed the minor differences in the growth inhibitory effects to the differences in charges (5- vs 6-) of V9Pt and V9Mo compared to V10 and/or the differences in the chemical composition. We concluded that the potency of the growth inhibition by V10 is mainly due to the chemical properties of the vanadium and the decametalate's unique structure even though the presence of the Mycobacterium smegmatis facilitate hydrolysis of the anions. SYNOPSIS: Two decavanadate derivatives, monoplatino(IV)nonavanadate(V) ([H2PtIVV9O28]5-), monomolybdo(VI)nonavanadate(V) ([MoVIV9O28]5-) and decavanadate are more potent growth inhibitors of Mycobacterium smegmatis than monomeric vanadate. The spectroscopic characterization carried out in the growth medium led to the conclusion that both the decavanadate structure and its properties are important for its growth effects.
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Affiliation(s)
- Kateryna Kostenkova
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, United States
| | - Zeyad Arhouma
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, United States; Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, United States
| | - Kahoana Postal
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, United States; Department of Chemistry, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | - Ananthu Rajan
- Department of Life Sciences and Chemistry, Jacobs University, 28759 Bremen, Germany
| | - Ulrich Kortz
- Department of Life Sciences and Chemistry, Jacobs University, 28759 Bremen, Germany
| | - Giovana G Nunes
- Department of Chemistry, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | - Dean C Crick
- Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, United States; Microbiology, Immunology, and Pathology Department, Colorado State University, Fort Collins, CO 80523, United States
| | - Debbie C Crans
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, United States; Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, United States.
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Gumerova NI, Rompel A. Polyoxometalates in solution: speciation under spotlight. Chem Soc Rev 2020; 49:7568-7601. [DOI: 10.1039/d0cs00392a] [Citation(s) in RCA: 111] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The review covers stability and transformations of classical polyoxometalates in aqueous solutions and provides their ion-distribution diagrams over a wide pH range.
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Affiliation(s)
- Nadiia I. Gumerova
- Universität Wien
- Fakultät für Chemie
- Institut für Biophysikalische Chemie
- 1090 Vienna
- Austria
| | - Annette Rompel
- Universität Wien
- Fakultät für Chemie
- Institut für Biophysikalische Chemie
- 1090 Vienna
- Austria
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Crans DC, Peters BJ, Wu X, McLauchlan CC. Does anion-cation organization in Na+-containing X-ray crystal structures relate to solution interactions in inhomogeneous nanoscale environments: Sodium-decavanadate in solid state materials, minerals, and microemulsions. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2017.03.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Sánchez-Lombardo I, Baruah B, Alvarez S, Werst KR, Segaline NA, Levinger NE, Crans DC. Size and shape trump charge in interactions of oxovanadates with self-assembled interfaces: application of continuous shape measure analysis to the decavanadate anion. NEW J CHEM 2016. [DOI: 10.1039/c5nj01788b] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using 51V NMR spectroscopy, dynamic light scattering and continuous shape analysis to characterize two polyoxometalate-encapsulation in reverse micelles.
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Affiliation(s)
| | - Bharat Baruah
- Department of Chemistry
- Colorado State University
- Colorado 80523-1872
- USA
- Department of Chemistry
| | - Santiago Alvarez
- Departament de Química Inorganica
- Institut de Química Teorica i Computacional (IQTCUB)
- Universitat de Barcelona
- 08028 Barcelona
- Spain
| | - Katarina R. Werst
- Department of Chemistry
- Colorado State University
- Colorado 80523-1872
- USA
| | | | - Nancy E. Levinger
- Department of Chemistry
- Colorado State University
- Colorado 80523-1872
- USA
| | - Debbie C. Crans
- Department of Chemistry
- Colorado State University
- Colorado 80523-1872
- USA
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Treviño S, Sánchez-Lara E, Sarmiento-Ortega VE, Sánchez-Lombardo I, Flores-Hernández JÁ, Pérez-Benítez A, Brambila-Colombres E, González-Vergara E. Hypoglycemic, lipid-lowering and metabolic regulation activities of metforminium decavanadate (H2Metf)3 [V10O28]·8H2O using hypercaloric-induced carbohydrate and lipid deregulation in Wistar rats as biological model. J Inorg Biochem 2015; 147:85-92. [PMID: 25920353 DOI: 10.1016/j.jinorgbio.2015.04.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Revised: 04/01/2015] [Accepted: 04/01/2015] [Indexed: 12/14/2022]
Abstract
Because of the increasing global spread of type 2 diabetes mellitus, there is a need to develop new antidiabetic agents. Recently we have synthesized new decavanadates using metformin as counterion. In particular, the compound containing three metforminium dications has been obtained in high yield and has been completely characterized. Biological studies using Wistar rats that have been fed with a high caloric diet inducing insulin resistance and metabolic syndrome were carried out. Results of the impact on key biochemical parameters mediated by metformin alone and the new compound are here presented. The metforminium decavanadate (H2Metf)3[V10O28]·8H2O, abbreviated as Metf-V10O28, was shown to have pharmacological potential as a hypoglycemic, lipid-lowering and metabolic regulator, since the resulting compound made of the two components with antidiabetic activities, reduces both dosage and time of administration (twice a week). Hence, due to the beneficial effects induced by the metforminium decavanadate we recommend to continue the exploration into the mechanism and toxicology of this new compound.
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Affiliation(s)
- Samuel Treviño
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio, Col. San Manuel, CP 72570 Puebla, PUE, Mexico
| | - Eduardo Sánchez-Lara
- Centro de Química, ICUAP, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio, Col. San Manuel, CP 72570 Puebla, PUE, Mexico
| | - Víctor Enrique Sarmiento-Ortega
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio, Col. San Manuel, CP 72570 Puebla, PUE, Mexico
| | - Irma Sánchez-Lombardo
- Centro de Química, ICUAP, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio, Col. San Manuel, CP 72570 Puebla, PUE, Mexico
| | - José Ángel Flores-Hernández
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio, Col. San Manuel, CP 72570 Puebla, PUE, Mexico
| | - Aarón Pérez-Benítez
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio, Col. San Manuel, CP 72570 Puebla, PUE, Mexico
| | - Eduardo Brambila-Colombres
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio, Col. San Manuel, CP 72570 Puebla, PUE, Mexico
| | - Enrique González-Vergara
- Centro de Química, ICUAP, Benemérita Universidad Autónoma de Puebla, 14 Sur y Av. San Claudio, Col. San Manuel, CP 72570 Puebla, PUE, Mexico.
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Fedorova EV, Buriakina AV, Vorob'eva NM, Baranova NI. [The vanadium compounds: chemistry, synthesis, insulinomimetic properties]. BIOMEDIT︠S︡INSKAI︠A︡ KHIMII︠A︡ 2014; 60:416-29. [PMID: 25249525 DOI: 10.18097/pbmc20146004416] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The review considers the biological role of vanadium, its participation in various processes in humans and other mammals, and the anti-diabetic effect of its compounds. Vanadium salts have persistent hypoglycemic and antihyperlipidemic effects and reduce the probability of secondary complications in animals with experimental diabetes. The review contains a detailed description of all major synthesized vanadium complexes having antidiabetic activity. Currently, vanadium complexes with organic ligands are more effective and safer than the inorganic salts. Despite the proven efficacy of these compounds as the anti-diabetic agents in animal models, only one organic complex of vanadium is currently under the second phase of clinical trials. All of the considered data suggest that vanadium compound are a new promising class of drugs in modern pharmacotherapy of diabetes.
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Fedorova EV, Buryakina AV, Vorobieva NM, Baranova NI. The vanadium compounds: Chemistry, synthesis, insulinomimetic properties. BIOCHEMISTRY MOSCOW-SUPPLEMENT SERIES B-BIOMEDICAL CHEMISTRY 2013. [DOI: 10.1134/s1990750813040021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Kittipongpittaya K, Panya A, McClements DJ, Decker EA. Impact of Free Fatty Acids and Phospholipids on Reverse Micelles Formation and Lipid Oxidation in Bulk Oil. J AM OIL CHEM SOC 2013. [DOI: 10.1007/s11746-013-2388-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Differentiating impact of the AOT-stabilized droplets of water-in-octane microemulsions as examined using halogenated fluoresceins as molecular probes. J Mol Liq 2013. [DOI: 10.1016/j.molliq.2013.08.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Nunes GG, Bonatto AC, de Albuquerque CG, Barison A, Ribeiro RR, Back DF, Andrade AVC, de Sá EL, Pedrosa FDO, Soares JF, de Souza EM. Synthesis, characterization and chemoprotective activity of polyoxovanadates against DNA alkylation. J Inorg Biochem 2012; 108:36-46. [DOI: 10.1016/j.jinorgbio.2011.11.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 10/31/2011] [Accepted: 11/23/2011] [Indexed: 10/14/2022]
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McPhee JT, Scott E, Levinger NE, Van Orden A. Cy3 in AOT Reverse Micelles II. Probing Intermicellar Interactions Using Fluorescence Correlation Spectroscopy. J Phys Chem B 2011; 115:9585-92. [DOI: 10.1021/jp2001282] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jeffrey T McPhee
- Colorado State University, Department of Chemistry, Fort Collins, Colorado 80523, USA
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Crans DC, Baruah B, Ross A, Levinger NE. Impact of confinement and interfaces on coordination chemistry: Using oxovanadate reactions and proton transfer reactions as probes in reverse micelles. Coord Chem Rev 2009. [DOI: 10.1016/j.ccr.2009.01.031] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Microwave Assisted Crystal Growth of a New Organic—Decavanadate Assembly: [V10O27(OH)] · 2(C6N2H14) · (C6N2H13) · (C6N2H12) · 2H2O. J Inorg Organomet Polym Mater 2009. [DOI: 10.1007/s10904-009-9271-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Aureliano M, Crans DC. Decavanadate (V10 O28 6-) and oxovanadates: oxometalates with many biological activities. J Inorg Biochem 2009; 103:536-46. [PMID: 19110314 DOI: 10.1016/j.jinorgbio.2008.11.010] [Citation(s) in RCA: 190] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2008] [Revised: 11/10/2008] [Accepted: 11/18/2008] [Indexed: 02/07/2023]
Abstract
The decameric vanadate species V(10)O(28)(6-), also referred to as decavanadate, impact proteins, lipid structures and cellular function, and show some effects in vivo on oxidative stress processes and other biological properties. The mode of action of decavanadate in many biochemical systems depends, at least in part, on the charge and size of the species and in some cases competes with the simpler oxovanadate species. The orange decavanadate that contains 10 vanadium atoms is a stable species for several days at neutral pH, but at higher pH immediately converts to the structurally and functionally distinct lower oxovanadates such as the monomer, dimer or tetramer. Although the biological effects of vanadium are generally assumed to derive from monomeric vanadate or the vanadyl cation, we show in this review that not all effects can be attributed to these simple oxovanadate forms. This topic has not previously been reviewed although background information is available [D.C. Crans, Comments Inorg. Chem. 16 (1994) 35-76; M. Aureliano (Ed.), Vanadium Biochemistry, Research Signpost Publs., Kerala, India, 2007]. In addition to pumps, channels and metabotropic receptors, lipid structures represent potential biological targets for decavanadate and some examples have been reported. Decavanadate interact with enzymes, polyphosphate, nucleotide and inositol 3-phosphate binding sites in the substrate domain or in an allosteric site, in a complex manner. In mitochondria, where vanadium was shown to accumulate following decavanadate in vivo administration, nM concentration of decavanadate induces membrane depolarization in addition to inhibiting oxygen consumption, suggesting that mitochondria may be potential targets for decameric toxicity. In vivo effects of decavanadate in piscine models demonstrated that antioxidant stress markers, lipid peroxidation and vanadium subcellular distribution is dependent upon whether or not the solutions administered contain decavanadate. The present review summarizes the reports on biological effects of decavanadate and highlights the importance of considering decavanadate in evaluations of the biological effects of vanadium.
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Affiliation(s)
- Manuel Aureliano
- CCMar and Dept. Chemistry, Biochemistry and Pharmacy, FCT, University of Algarve, Faro, Portugal.
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Griffith CS, Sizgek GD, Sizgek E, Scales N, Yee PJ, Luca V. Mesoporous zirconium titanium oxides. Part 1: Porosity modulation and adsorption properties of xerogels. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:12312-12322. [PMID: 18828619 DOI: 10.1021/la801464s] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A series of zirconium titanium oxide mesophases containing 33 atom % Zr have been prepared using carboxylic acids of different alkyl chain lengths (Cy ) from y=4-18 through organic-inorganic polymer phase segregation as the gel transition is approached. Thermal treatment of these transparent gels up to 450 degrees C eliminated the organic template, and domain coarsening occurred affording stable worm-hole mesoporous materials of homogeneous composition and pore diameters varying from about 3 to 4 nm in fine increments. With such materials, it was subsequently possible to precisely study the adsorption of vanadium oxo-anions and cations from aqueous solutions and, more particularly, probe the kinetics of intraparticle mass transport as a function of the associated pore dimension. The kinetics of mass transport through the pore systems was investigated using aqueous vanadyl (VO2+) and orthovanadate (VO3(OH)2-) probe species at concentrations ranging from 10 to 200 ppm (0.2 to 4 mmol/L) and pH values of 0 and 10.5, respectively. In the case of both of these vanadium species, the zirconium titanate mesophases displayed relatively slow kinetics, taking in excess of about 500 min to achieve maximum uptake. By using a pseudo-second-order rate law, it was possible to extract the instantaneous and overall rate of the adsorption processes and then relate these to the pore diameters. Both the instantaneous and overall rates of adsorption increased with increasing surface area and pore diameter over the studied pore size range. However, the equilibrium adsorption capacity increased linearly with pore diameter only for the higher concentrations and was independent of pore diameter for the lower concentration. These results have been interpreted using a model in which discrete adsorption occurs at low concentrations and is then followed by multilayer adsorption at higher concentration.
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Affiliation(s)
- Christopher S Griffith
- Australian Nuclear Science and Technology Organisation, Institute of Materials Engineering, Menai, NSW, Australia
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Baruah B, Swafford LA, Crans DC, Levinger NE. Do Probe Molecules Influence Water in Confinement? J Phys Chem B 2008; 112:10158-64. [DOI: 10.1021/jp800390t] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Bharat Baruah
- Department of Chemistry, Colorado State University, Colorado 80523-1872
| | - Laura A. Swafford
- Department of Chemistry, Colorado State University, Colorado 80523-1872
| | - Debbie C. Crans
- Department of Chemistry, Colorado State University, Colorado 80523-1872
| | - Nancy E. Levinger
- Department of Chemistry, Colorado State University, Colorado 80523-1872
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Aureliano M, Henao F, Tiago T, Duarte RO, Moura JJG, Baruah B, Crans DC. Sarcoplasmic reticulum calcium ATPase is inhibited by organic vanadium coordination compounds: pyridine-2,6-dicarboxylatodioxovanadium(V), BMOV, and an amavadine analogue. Inorg Chem 2008; 47:5677-84. [PMID: 18510311 DOI: 10.1021/ic702405d] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The general affinity of the sarcoplasmic reticulum (SR) Ca (2+)-ATPase was examined for three different classes of vanadium coordination complexes including a vanadium(V) compound, pyridine-2,6-dicarboxylatodioxovanadium(V) (PDC-V(V)), and two vanadium(IV) compounds, bis(maltolato)oxovanadium(IV) (BMOV), and an analogue of amavadine, bis( N-hydroxylamidoiminodiacetato)vanadium(IV) (HAIDA-V(IV)). The ability of vanadate to act either as a phosphate analogue or as a transition-state analogue with enzymes' catalysis phosphoryl group transfer suggests that vanadium coordination compounds may reveal mechanistic preferences in these classes of enzymes. Two of these compounds investigated, PDC-V(V) and BMOV, were hydrolytically and oxidatively reactive at neutral pH, and one, HAIDA-V(IV), does not hydrolyze, oxidize, or otherwise decompose to a measurable extent during the enzyme assay. The SR Ca (2+)-ATPase was inhibited by all three of these complexes. The relative order of inhibition was PDC-V(V) > BMOV > vanadate > HAIDA-V(IV), and the IC 50 values were 25, 40, 80, and 325 microM, respectively. Because the observed inhibition is more potent for PDC-V(V) and BMOV than that of oxovanadates, the inhibition cannot be explained by oxovanadate formation during enzyme assays. Furthermore, the hydrolytically and redox stable amavadine analogue HAIDA-V(IV) inhibited the Ca (2+)-ATPase less than oxovanadates. To gauge the importance of the lipid environment, studies of oxidized BMOV in microemulsions were performed and showed that this system remained in the aqueous pool even though PDC-V(V) is able to penetrate lipid interfaces. These findings suggest that the hydrolytic properties of these complexes may be important in the inhibition of the calcium pump. Our results show that two simple coordination complexes with known insulin enhancing effects can invoke a response in calcium homeostasis and the regulation of muscle contraction through the SR Ca (2+)-ATPase.
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Affiliation(s)
- Manuel Aureliano
- Dept. Química, Bioquímica e Farmácia, FCT, Universidade do Algarve, 8005-139 Faro, Portugal.
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Impairment of ascorbic acid’s anti-oxidant properties in confined media: Inter and intramolecular reactions with air and vanadate at acidic pH. J Inorg Biochem 2008; 102:1334-47. [DOI: 10.1016/j.jinorgbio.2008.01.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2007] [Revised: 01/04/2008] [Accepted: 01/10/2008] [Indexed: 11/22/2022]
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