New Calcium‐Selective Smart Contrast Agents for Magnetic Resonance Imaging
Identifieur interne : 000414 ( France/Analysis ); précédent : 000413; suivant : 000415New Calcium‐Selective Smart Contrast Agents for Magnetic Resonance Imaging
Auteurs : Kirti Dhingra Verma [Allemagne, États-Unis] ; Attila Forgács [Italie] ; Hyounsoo Uh [États-Unis] ; Michael Beyerlein [Allemagne] ; Martin E. Maier [Allemagne] ; Stéphane Petoud [États-Unis, France] ; Mauro Botta [Italie] ; Nikos K. Logothetis [Allemagne, Royaume-Uni]Source :
- Chemistry – A European Journal [ 0947-6539 ] ; 2013-12-23.
Descripteurs français
- Wicri :
- topic : Solvant.
English descriptors
- KwdEn :
- Acsf, Activation energy, Aecm, Alcohol group, Aptra, Aptra unit, Aqueous solutions, Aromatic ring, Artificial extracellular matrix, Benzyl bromide, Benzyl group, Botta, Bromoacetic acid, Bromoacetyl bromide, Bruker, Bruker avance, Calcd, Carbon tetrabromide, Carbon unit, Catalog number, Cdcl3, Chem, Chemical shift, Chemical shifts, Column chromatography, Complete addition, Concentration changes, Contrast agents, Dalton trans, Data analysis, Diethyl ether, Dissociation constants, Dropwise addition, Enhancement, Ethyl, Ethyl acetate, Ethyl diazoacetate, Experimental data, Experimental section, Extracellular, Extracellular matrix, Extracellular space, Field strength, Final agent, Financial support, Full paper, Further purification, Gmbh, Heterogeneous mixture, Hydration, Hydration number, Hydration state, Imaging, Kgaa, Kmops buffer, Large relaxivity enhancement, Ligand, Linker, Lniii complexes, Logothetis, Longitudinal relaxation time, Lower curves, Luminescence, Luminescence lifetime measurement, Luminescence lifetimes, Magnetic resonance imaging, Merbach, Minimum amount, Mmol, Molecular mass, Molecular rotation, Molecule, Neural activity, Nmrd, Nmrd profiles, Open symbols, Organic layer, Other hand, Overall relaxivity, Paper figure, Parr apparatus, Pendant, Pendant arms, Phenolic group, Physiological fluids, Plasma membrane, Precursor, Proton, Proton larmor frequencies, Proton peak intensity, Proton sponge, Pure product, Reaction mixture, Relaxation, Relaxation dispersion, Relaxation rate, Relaxation rates, Relaxivity, Relaxivity changes, Relaxivity data, Relaxivity enhancement, Relaxivity response, Relaxometric study, Residence lifetime, Rotational correlation time, Same temperature, Second sphere, Shift experiments, Significant contribution, Similar synthesis, Simple buffer solution, Small portions, Smart contrast agents, Sodium borohydride, Sodium hydride, Solid naoh, Solvent, Solvent mixture, Specific relaxivity response, Structural stability, Synthetic scheme, Temperature dependence, Tighter coordination, Transverse relaxation, Transverse relaxation rate, Transverse relaxation rates, Unused reactant, Upper curves, Vander elst, Verlag, Verlag gmbh, Verma, Vivo conditions, Water exchange, Water exchange rate, Water molecule, Water molecules, Water protons, Weinheim, Weinheim chem.
- Teeft :
- Acsf, Activation energy, Aecm, Alcohol group, Aptra, Aptra unit, Aqueous solutions, Aromatic ring, Artificial extracellular matrix, Benzyl bromide, Benzyl group, Botta, Bromoacetic acid, Bromoacetyl bromide, Bruker, Bruker avance, Calcd, Carbon tetrabromide, Carbon unit, Catalog number, Cdcl3, Chem, Chemical shift, Chemical shifts, Column chromatography, Complete addition, Concentration changes, Contrast agents, Dalton trans, Data analysis, Diethyl ether, Dissociation constants, Dropwise addition, Enhancement, Ethyl, Ethyl acetate, Ethyl diazoacetate, Experimental data, Experimental section, Extracellular, Extracellular matrix, Extracellular space, Field strength, Final agent, Financial support, Full paper, Further purification, Gmbh, Heterogeneous mixture, Hydration, Hydration number, Hydration state, Imaging, Kgaa, Kmops buffer, Large relaxivity enhancement, Ligand, Linker, Lniii complexes, Logothetis, Longitudinal relaxation time, Lower curves, Luminescence, Luminescence lifetime measurement, Luminescence lifetimes, Magnetic resonance imaging, Merbach, Minimum amount, Mmol, Molecular mass, Molecular rotation, Molecule, Neural activity, Nmrd, Nmrd profiles, Open symbols, Organic layer, Other hand, Overall relaxivity, Paper figure, Parr apparatus, Pendant, Pendant arms, Phenolic group, Physiological fluids, Plasma membrane, Precursor, Proton, Proton larmor frequencies, Proton peak intensity, Proton sponge, Pure product, Reaction mixture, Relaxation, Relaxation dispersion, Relaxation rate, Relaxation rates, Relaxivity, Relaxivity changes, Relaxivity data, Relaxivity enhancement, Relaxivity response, Relaxometric study, Residence lifetime, Rotational correlation time, Same temperature, Second sphere, Shift experiments, Significant contribution, Similar synthesis, Simple buffer solution, Small portions, Smart contrast agents, Sodium borohydride, Sodium hydride, Solid naoh, Solvent, Solvent mixture, Specific relaxivity response, Structural stability, Synthetic scheme, Temperature dependence, Tighter coordination, Transverse relaxation, Transverse relaxation rate, Transverse relaxation rates, Unused reactant, Upper curves, Vander elst, Verlag, Verlag gmbh, Verma, Vivo conditions, Water exchange, Water exchange rate, Water molecule, Water molecules, Water protons, Weinheim, Weinheim chem.
Abstract
Calcium plays a vital role in the human body and especially in the central nervous system. Precise maintenance of Ca2+ levels is very crucial for normal cell physiology and health. The deregulation of calcium homeostasis can lead to neuronal cell death and brain damage. To study this functional role played by Ca2+ in the brain noninvasively by using magnetic resonance imaging, we have synthesized a new set of Ca2+‐sensitive smart contrast agents (CAs). The agents were found to be highly selective to Ca2+ in the presence of other competitive anions and cations in buffer and in physiological fluids. The structure of CAs comprises Gd3+‐DO3A (DO3A=1,4,7‐tris(carboxymethyl)‐1,4,7,10‐tetraazacyclododecane) coupled to a Ca2+ chelator o‐amino phenol‐N,N,O‐triacetate (APTRA). The agents are designed to sense Ca2+ present in extracellular fluid of the brain where its concentration is relatively high, that is, 1.2–0.8 mM. The determined dissociation constant of the CAs to Ca2+ falls in the range required to sense and report changes in extracellular Ca2+ levels followed by an increase in neural activity. In buffer, with the addition of Ca2+ the increase in relaxivity ranged from 100–157 %, the highest ever known for any T1‐based Ca2+‐sensitive smart CA. The CAs were analyzed extensively by the measurement of luminescence lifetime measurement on Tb3+ analogues, nuclear magnetic relaxation dispersion (NMRD), and 17O NMR transverse relaxation and shift experiments. The results obtained confirmed that the large relaxivity enhancement observed upon Ca2+ addition is due to the increase of the hydration state of the complexes together with the slowing down of the molecular rotation and the retention of a significant contribution of the water molecules of the second sphere of hydration.
Url:
DOI: 10.1002/chem.201300169
Affiliations:
- Allemagne, France, Italie, Royaume-Uni, États-Unis
- Angleterre, Grand Manchester, Pennsylvanie
- Manchester, Pittsburgh
- Université de Manchester, Université de Pittsburgh
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Max Planck Institute for Biological Cybernetics, Dept. of Physiology of Cognitive Processes</wicri:regionArea><wicri:noRegion>Dept. of Physiology of Cognitive Processes</wicri:noRegion><wicri:noRegion>Dept. of Physiology of Cognitive Processes</wicri:noRegion></affiliation></author></analytic><monogr></monogr><series><title level="j" type="main">Chemistry – A European Journal</title><title level="j" type="alt">CHEMISTRY - A EUROPEAN JOURNAL</title><idno type="ISSN">0947-6539</idno><idno type="eISSN">1521-3765</idno><imprint><biblScope unit="vol">19</biblScope><biblScope unit="issue">52</biblScope><biblScope unit="page" from="18011">18011</biblScope><biblScope unit="page" to="18026">18026</biblScope><biblScope unit="page-count">16</biblScope><publisher>WILEY‐VCH Verlag</publisher><pubPlace>Weinheim</pubPlace><date type="published" when="2013-12-23">2013-12-23</date></imprint><idno type="ISSN">0947-6539</idno></series></biblStruct></sourceDesc><seriesStmt><idno type="ISSN">0947-6539</idno></seriesStmt></fileDesc><profileDesc><textClass><keywords scheme="KwdEn" xml:lang="en"><term>Acsf</term><term>Activation energy</term><term>Aecm</term><term>Alcohol group</term><term>Aptra</term><term>Aptra unit</term><term>Aqueous solutions</term><term>Aromatic ring</term><term>Artificial extracellular matrix</term><term>Benzyl bromide</term><term>Benzyl group</term><term>Botta</term><term>Bromoacetic acid</term><term>Bromoacetyl bromide</term><term>Bruker</term><term>Bruker avance</term><term>Calcd</term><term>Carbon tetrabromide</term><term>Carbon unit</term><term>Catalog number</term><term>Cdcl3</term><term>Chem</term><term>Chemical shift</term><term>Chemical shifts</term><term>Column chromatography</term><term>Complete addition</term><term>Concentration changes</term><term>Contrast agents</term><term>Dalton trans</term><term>Data analysis</term><term>Diethyl ether</term><term>Dissociation constants</term><term>Dropwise addition</term><term>Enhancement</term><term>Ethyl</term><term>Ethyl acetate</term><term>Ethyl diazoacetate</term><term>Experimental data</term><term>Experimental section</term><term>Extracellular</term><term>Extracellular matrix</term><term>Extracellular space</term><term>Field strength</term><term>Final agent</term><term>Financial support</term><term>Full paper</term><term>Further purification</term><term>Gmbh</term><term>Heterogeneous mixture</term><term>Hydration</term><term>Hydration number</term><term>Hydration state</term><term>Imaging</term><term>Kgaa</term><term>Kmops buffer</term><term>Large relaxivity enhancement</term><term>Ligand</term><term>Linker</term><term>Lniii complexes</term><term>Logothetis</term><term>Longitudinal relaxation time</term><term>Lower curves</term><term>Luminescence</term><term>Luminescence lifetime measurement</term><term>Luminescence lifetimes</term><term>Magnetic resonance imaging</term><term>Merbach</term><term>Minimum amount</term><term>Mmol</term><term>Molecular mass</term><term>Molecular rotation</term><term>Molecule</term><term>Neural activity</term><term>Nmrd</term><term>Nmrd profiles</term><term>Open symbols</term><term>Organic layer</term><term>Other hand</term><term>Overall relaxivity</term><term>Paper figure</term><term>Parr apparatus</term><term>Pendant</term><term>Pendant arms</term><term>Phenolic group</term><term>Physiological fluids</term><term>Plasma membrane</term><term>Precursor</term><term>Proton</term><term>Proton larmor frequencies</term><term>Proton peak intensity</term><term>Proton sponge</term><term>Pure product</term><term>Reaction mixture</term><term>Relaxation</term><term>Relaxation dispersion</term><term>Relaxation rate</term><term>Relaxation rates</term><term>Relaxivity</term><term>Relaxivity changes</term><term>Relaxivity data</term><term>Relaxivity enhancement</term><term>Relaxivity response</term><term>Relaxometric study</term><term>Residence lifetime</term><term>Rotational correlation time</term><term>Same temperature</term><term>Second sphere</term><term>Shift experiments</term><term>Significant contribution</term><term>Similar synthesis</term><term>Simple buffer solution</term><term>Small portions</term><term>Smart contrast agents</term><term>Sodium borohydride</term><term>Sodium hydride</term><term>Solid naoh</term><term>Solvent</term><term>Solvent mixture</term><term>Specific relaxivity response</term><term>Structural stability</term><term>Synthetic scheme</term><term>Temperature dependence</term><term>Tighter coordination</term><term>Transverse relaxation</term><term>Transverse relaxation rate</term><term>Transverse relaxation rates</term><term>Unused reactant</term><term>Upper curves</term><term>Vander elst</term><term>Verlag</term><term>Verlag gmbh</term><term>Verma</term><term>Vivo conditions</term><term>Water exchange</term><term>Water exchange rate</term><term>Water molecule</term><term>Water molecules</term><term>Water protons</term><term>Weinheim</term><term>Weinheim chem</term></keywords><keywords scheme="Teeft" xml:lang="en"><term>Acsf</term><term>Activation energy</term><term>Aecm</term><term>Alcohol group</term><term>Aptra</term><term>Aptra unit</term><term>Aqueous solutions</term><term>Aromatic ring</term><term>Artificial extracellular matrix</term><term>Benzyl bromide</term><term>Benzyl group</term><term>Botta</term><term>Bromoacetic acid</term><term>Bromoacetyl bromide</term><term>Bruker</term><term>Bruker avance</term><term>Calcd</term><term>Carbon tetrabromide</term><term>Carbon unit</term><term>Catalog number</term><term>Cdcl3</term><term>Chem</term><term>Chemical shift</term><term>Chemical shifts</term><term>Column chromatography</term><term>Complete addition</term><term>Concentration changes</term><term>Contrast agents</term><term>Dalton trans</term><term>Data analysis</term><term>Diethyl ether</term><term>Dissociation constants</term><term>Dropwise addition</term><term>Enhancement</term><term>Ethyl</term><term>Ethyl acetate</term><term>Ethyl diazoacetate</term><term>Experimental data</term><term>Experimental section</term><term>Extracellular</term><term>Extracellular matrix</term><term>Extracellular space</term><term>Field strength</term><term>Final agent</term><term>Financial support</term><term>Full paper</term><term>Further purification</term><term>Gmbh</term><term>Heterogeneous mixture</term><term>Hydration</term><term>Hydration number</term><term>Hydration state</term><term>Imaging</term><term>Kgaa</term><term>Kmops buffer</term><term>Large relaxivity enhancement</term><term>Ligand</term><term>Linker</term><term>Lniii complexes</term><term>Logothetis</term><term>Longitudinal relaxation time</term><term>Lower curves</term><term>Luminescence</term><term>Luminescence lifetime measurement</term><term>Luminescence lifetimes</term><term>Magnetic resonance imaging</term><term>Merbach</term><term>Minimum amount</term><term>Mmol</term><term>Molecular mass</term><term>Molecular rotation</term><term>Molecule</term><term>Neural activity</term><term>Nmrd</term><term>Nmrd profiles</term><term>Open symbols</term><term>Organic layer</term><term>Other hand</term><term>Overall relaxivity</term><term>Paper figure</term><term>Parr apparatus</term><term>Pendant</term><term>Pendant arms</term><term>Phenolic group</term><term>Physiological fluids</term><term>Plasma membrane</term><term>Precursor</term><term>Proton</term><term>Proton larmor frequencies</term><term>Proton peak intensity</term><term>Proton sponge</term><term>Pure product</term><term>Reaction mixture</term><term>Relaxation</term><term>Relaxation dispersion</term><term>Relaxation rate</term><term>Relaxation rates</term><term>Relaxivity</term><term>Relaxivity changes</term><term>Relaxivity data</term><term>Relaxivity enhancement</term><term>Relaxivity response</term><term>Relaxometric study</term><term>Residence lifetime</term><term>Rotational correlation time</term><term>Same temperature</term><term>Second sphere</term><term>Shift experiments</term><term>Significant contribution</term><term>Similar synthesis</term><term>Simple buffer solution</term><term>Small portions</term><term>Smart contrast agents</term><term>Sodium borohydride</term><term>Sodium hydride</term><term>Solid naoh</term><term>Solvent</term><term>Solvent mixture</term><term>Specific relaxivity response</term><term>Structural stability</term><term>Synthetic scheme</term><term>Temperature dependence</term><term>Tighter coordination</term><term>Transverse relaxation</term><term>Transverse relaxation rate</term><term>Transverse relaxation rates</term><term>Unused reactant</term><term>Upper curves</term><term>Vander elst</term><term>Verlag</term><term>Verlag gmbh</term><term>Verma</term><term>Vivo conditions</term><term>Water exchange</term><term>Water exchange rate</term><term>Water molecule</term><term>Water molecules</term><term>Water protons</term><term>Weinheim</term><term>Weinheim chem</term></keywords><keywords scheme="Wicri" type="topic" xml:lang="fr"><term>Solvant</term></keywords></textClass></profileDesc></teiHeader><front><div type="abstract" xml:lang="en">Calcium plays a vital role in the human body and especially in the central nervous system. Precise maintenance of Ca2+ levels is very crucial for normal cell physiology and health. The deregulation of calcium homeostasis can lead to neuronal cell death and brain damage. To study this functional role played by Ca2+ in the brain noninvasively by using magnetic resonance imaging, we have synthesized a new set of Ca2+‐sensitive smart contrast agents (CAs). The agents were found to be highly selective to Ca2+ in the presence of other competitive anions and cations in buffer and in physiological fluids. The structure of CAs comprises Gd3+‐DO3A (DO3A=1,4,7‐tris(carboxymethyl)‐1,4,7,10‐tetraazacyclododecane) coupled to a Ca2+ chelator o‐amino phenol‐N,N,O‐triacetate (APTRA). The agents are designed to sense Ca2+ present in extracellular fluid of the brain where its concentration is relatively high, that is, 1.2–0.8 mM. The determined dissociation constant of the CAs to Ca2+ falls in the range required to sense and report changes in extracellular Ca2+ levels followed by an increase in neural activity. In buffer, with the addition of Ca2+ the increase in relaxivity ranged from 100–157 %, the highest ever known for any T1‐based Ca2+‐sensitive smart CA. The CAs were analyzed extensively by the measurement of luminescence lifetime measurement on Tb3+ analogues, nuclear magnetic relaxation dispersion (NMRD), and 17O NMR transverse relaxation and shift experiments. The results obtained confirmed that the large relaxivity enhancement observed upon Ca2+ addition is due to the increase of the hydration state of the complexes together with the slowing down of the molecular rotation and the retention of a significant contribution of the water molecules of the second sphere of hydration.</div></front></TEI><affiliations><list><country><li>Allemagne</li><li>France</li><li>Italie</li><li>Royaume-Uni</li><li>États-Unis</li></country><region><li>Angleterre</li><li>Grand Manchester</li><li>Pennsylvanie</li></region><settlement><li>Manchester</li><li>Pittsburgh</li></settlement><orgName><li>Université de Manchester</li><li>Université de Pittsburgh</li></orgName></list><tree><country name="Allemagne"><noRegion><name sortKey="Verma, Kirti Dhingra" sort="Verma, Kirti Dhingra" uniqKey="Verma K" first="Kirti Dhingra" last="Verma">Kirti Dhingra Verma</name></noRegion><name sortKey="Beyerlein, Michael" sort="Beyerlein, Michael" uniqKey="Beyerlein M" first="Michael" last="Beyerlein">Michael Beyerlein</name><name sortKey="Logothetis, Nikos K" sort="Logothetis, Nikos K" uniqKey="Logothetis N" first="Nikos K." last="Logothetis">Nikos K. Logothetis</name><name sortKey="Logothetis, Nikos K" sort="Logothetis, Nikos K" uniqKey="Logothetis N" first="Nikos K." last="Logothetis">Nikos K. Logothetis</name><name sortKey="Logothetis, Nikos K" sort="Logothetis, Nikos K" uniqKey="Logothetis N" first="Nikos K." last="Logothetis">Nikos K. Logothetis</name><name sortKey="Maier, Martin E" sort="Maier, Martin E" uniqKey="Maier M" first="Martin E." last="Maier">Martin E. Maier</name><name sortKey="Verma, Kirti Dhingra" sort="Verma, Kirti Dhingra" uniqKey="Verma K" first="Kirti Dhingra" last="Verma">Kirti Dhingra Verma</name></country><country name="États-Unis"><noRegion><name sortKey="Verma, Kirti Dhingra" sort="Verma, Kirti Dhingra" uniqKey="Verma K" first="Kirti Dhingra" last="Verma">Kirti Dhingra Verma</name></noRegion><name sortKey="Petoud, Stephane" sort="Petoud, Stephane" uniqKey="Petoud S" first="Stéphane" last="Petoud">Stéphane Petoud</name><name sortKey="Uh, Hyounsoo" sort="Uh, Hyounsoo" uniqKey="Uh H" first="Hyounsoo" last="Uh">Hyounsoo Uh</name></country><country name="Italie"><noRegion><name sortKey="Forgacs, Attila" sort="Forgacs, Attila" uniqKey="Forgacs A" first="Attila" last="Forgács">Attila Forgács</name></noRegion><name sortKey="Botta, Mauro" sort="Botta, Mauro" uniqKey="Botta M" first="Mauro" last="Botta">Mauro Botta</name></country><country name="France"><noRegion><name sortKey="Petoud, Stephane" sort="Petoud, Stephane" uniqKey="Petoud S" first="Stéphane" last="Petoud">Stéphane Petoud</name></noRegion></country><country name="Royaume-Uni"><region name="Angleterre"><name sortKey="Logothetis, Nikos K" sort="Logothetis, Nikos K" uniqKey="Logothetis N" first="Nikos K." last="Logothetis">Nikos K. 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