Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism

Autores
Calero, Cecilia Ines; Beltrán González, Andrea Natalia; Gasulla, Javier; Alvarez, Silvia; Evelson, Pablo Andres; Calvo, Daniel Juan
Año de publicación
2013
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Quercetin is a natural flavonoid widely distributed in plants that acts as a neuroprotective agent and modulates the activity of different synaptic receptors and ion channels, including the ionotropic GABA receptors. GABAArho1 receptors were shown to be antagonized by quercetin, but the mechanisms underlying these antagonistic actions are still unknown. We have analyzed here if the antagonistic action produced by quercetin on GABAArho1 receptors was related to its redox activity or due to alternative mechanism/s. Homomeric GABAArho1 receptors were expressed in frog oocytes and GABA-evoked responses electrophysiologically recorded. Quercetin effects on GABAArho1 receptors were examined in the absence or presence of ascorbic acid. Chemical protection of cysteines by selective sulfhydryl reagents and site directed mutagenesis experiments were also used to determine ρ₁ subunit residues involved in quercetin actions. Quercetin antagonized GABAArho1 receptor responses in a dose-dependent, fast and reversible manner. Quercetin inhibition was prevented in the presence of ascorbic acid, but not by thiol reagents that modify the extracellular Cys-loop of these receptors. H141, an aminoacidic residue located near to the rho1 subunit GABA binding site, was involved in the allosteric modulation of GABAArho1 receptors by several agents including ascorbic acid. Quercetin similarly antagonized GABA-evoked responses mediated by mutant (H141D)GABAArho1 and wild-type receptors, but prevention exerted by ascorbic acid on quercetin effects was impaired in mutant receptors. Taken together the present results suggest that quercetin antagonistic actions on GABAArho1 receptors are mediated through a redox-independent allosteric mechanism.
Fil: Calero, Cecilia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; Argentina
Fil: Beltrán González, Andrea Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; Argentina
Fil: Gasulla, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; Argentina
Fil: Alvarez, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentina
Fil: Evelson, Pablo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentina
Fil: Calvo, Daniel Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; Argentina
Materia
Gaba Receptor
Flavonoid
Quercetin
Ascorbic Acid
Allosteric Modulator
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-nd/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/6601
Acceder
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network_acronym_str CONICETDig
repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanismCalero, Cecilia InesBeltrán González, Andrea NataliaGasulla, JavierAlvarez, SilviaEvelson, Pablo AndresCalvo, Daniel JuanGaba ReceptorFlavonoidQuercetinAscorbic AcidAllosteric Modulatorhttps://purl.org/becyt/ford/3.1https://purl.org/becyt/ford/3Quercetin is a natural flavonoid widely distributed in plants that acts as a neuroprotective agent and modulates the activity of different synaptic receptors and ion channels, including the ionotropic GABA receptors. GABAArho1 receptors were shown to be antagonized by quercetin, but the mechanisms underlying these antagonistic actions are still unknown. We have analyzed here if the antagonistic action produced by quercetin on GABAArho1 receptors was related to its redox activity or due to alternative mechanism/s. Homomeric GABAArho1 receptors were expressed in frog oocytes and GABA-evoked responses electrophysiologically recorded. Quercetin effects on GABAArho1 receptors were examined in the absence or presence of ascorbic acid. Chemical protection of cysteines by selective sulfhydryl reagents and site directed mutagenesis experiments were also used to determine ρ₁ subunit residues involved in quercetin actions. Quercetin antagonized GABAArho1 receptor responses in a dose-dependent, fast and reversible manner. Quercetin inhibition was prevented in the presence of ascorbic acid, but not by thiol reagents that modify the extracellular Cys-loop of these receptors. H141, an aminoacidic residue located near to the rho1 subunit GABA binding site, was involved in the allosteric modulation of GABAArho1 receptors by several agents including ascorbic acid. Quercetin similarly antagonized GABA-evoked responses mediated by mutant (H141D)GABAArho1 and wild-type receptors, but prevention exerted by ascorbic acid on quercetin effects was impaired in mutant receptors. Taken together the present results suggest that quercetin antagonistic actions on GABAArho1 receptors are mediated through a redox-independent allosteric mechanism.Fil: Calero, Cecilia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; ArgentinaFil: Beltrán González, Andrea Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; ArgentinaFil: Gasulla, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; ArgentinaFil: Alvarez, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Evelson, Pablo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Calvo, Daniel Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; ArgentinaElsevier2013-08info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/mswordapplication/pdfapplication/pdfapplication/pdfapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/6601Calero, Cecilia Ines; Beltrán González, Andrea Natalia; Gasulla, Javier; Alvarez, Silvia; Evelson, Pablo Andres; et al.; Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism; Elsevier; European Journal of Pharmacology; 714; 1-3; 8-2013; 274-2800014-2999enginfo:eu-repo/semantics/altIdentifier/url/http://www.sciencedirect.com/science/article/pii/S0014299913005669info:eu-repo/semantics/altIdentifier/doi/info:eu-repo/semantics/altIdentifier/doi/10.1016/j.ejphar.2013.07.044info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-nd/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-10T13:03:45Zoai:ri.conicet.gov.ar:11336/6601instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-10 13:03:46.107CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism
title Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism
spellingShingle Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism
Calero, Cecilia Ines
Gaba Receptor
Flavonoid
Quercetin
Ascorbic Acid
Allosteric Modulator
title_short Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism
title_full Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism
title_fullStr Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism
title_full_unstemmed Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism
title_sort Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism
dc.creator.none.fl_str_mv Calero, Cecilia Ines
Beltrán González, Andrea Natalia
Gasulla, Javier
Alvarez, Silvia
Evelson, Pablo Andres
Calvo, Daniel Juan
author Calero, Cecilia Ines
author_facet Calero, Cecilia Ines
Beltrán González, Andrea Natalia
Gasulla, Javier
Alvarez, Silvia
Evelson, Pablo Andres
Calvo, Daniel Juan
author_role author
author2 Beltrán González, Andrea Natalia
Gasulla, Javier
Alvarez, Silvia
Evelson, Pablo Andres
Calvo, Daniel Juan
author2_role author
author
author
author
author
dc.subject.none.fl_str_mv Gaba Receptor
Flavonoid
Quercetin
Ascorbic Acid
Allosteric Modulator
topic Gaba Receptor
Flavonoid
Quercetin
Ascorbic Acid
Allosteric Modulator
purl_subject.fl_str_mv https://purl.org/becyt/ford/3.1
https://purl.org/becyt/ford/3
dc.description.none.fl_txt_mv Quercetin is a natural flavonoid widely distributed in plants that acts as a neuroprotective agent and modulates the activity of different synaptic receptors and ion channels, including the ionotropic GABA receptors. GABAArho1 receptors were shown to be antagonized by quercetin, but the mechanisms underlying these antagonistic actions are still unknown. We have analyzed here if the antagonistic action produced by quercetin on GABAArho1 receptors was related to its redox activity or due to alternative mechanism/s. Homomeric GABAArho1 receptors were expressed in frog oocytes and GABA-evoked responses electrophysiologically recorded. Quercetin effects on GABAArho1 receptors were examined in the absence or presence of ascorbic acid. Chemical protection of cysteines by selective sulfhydryl reagents and site directed mutagenesis experiments were also used to determine ρ₁ subunit residues involved in quercetin actions. Quercetin antagonized GABAArho1 receptor responses in a dose-dependent, fast and reversible manner. Quercetin inhibition was prevented in the presence of ascorbic acid, but not by thiol reagents that modify the extracellular Cys-loop of these receptors. H141, an aminoacidic residue located near to the rho1 subunit GABA binding site, was involved in the allosteric modulation of GABAArho1 receptors by several agents including ascorbic acid. Quercetin similarly antagonized GABA-evoked responses mediated by mutant (H141D)GABAArho1 and wild-type receptors, but prevention exerted by ascorbic acid on quercetin effects was impaired in mutant receptors. Taken together the present results suggest that quercetin antagonistic actions on GABAArho1 receptors are mediated through a redox-independent allosteric mechanism.
Fil: Calero, Cecilia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; Argentina
Fil: Beltrán González, Andrea Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; Argentina
Fil: Gasulla, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; Argentina
Fil: Alvarez, Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentina
Fil: Evelson, Pablo Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular; Argentina
Fil: Calvo, Daniel Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; Argentina
description Quercetin is a natural flavonoid widely distributed in plants that acts as a neuroprotective agent and modulates the activity of different synaptic receptors and ion channels, including the ionotropic GABA receptors. GABAArho1 receptors were shown to be antagonized by quercetin, but the mechanisms underlying these antagonistic actions are still unknown. We have analyzed here if the antagonistic action produced by quercetin on GABAArho1 receptors was related to its redox activity or due to alternative mechanism/s. Homomeric GABAArho1 receptors were expressed in frog oocytes and GABA-evoked responses electrophysiologically recorded. Quercetin effects on GABAArho1 receptors were examined in the absence or presence of ascorbic acid. Chemical protection of cysteines by selective sulfhydryl reagents and site directed mutagenesis experiments were also used to determine ρ₁ subunit residues involved in quercetin actions. Quercetin antagonized GABAArho1 receptor responses in a dose-dependent, fast and reversible manner. Quercetin inhibition was prevented in the presence of ascorbic acid, but not by thiol reagents that modify the extracellular Cys-loop of these receptors. H141, an aminoacidic residue located near to the rho1 subunit GABA binding site, was involved in the allosteric modulation of GABAArho1 receptors by several agents including ascorbic acid. Quercetin similarly antagonized GABA-evoked responses mediated by mutant (H141D)GABAArho1 and wild-type receptors, but prevention exerted by ascorbic acid on quercetin effects was impaired in mutant receptors. Taken together the present results suggest that quercetin antagonistic actions on GABAArho1 receptors are mediated through a redox-independent allosteric mechanism.
publishDate 2013
dc.date.none.fl_str_mv 2013-08
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/6601
Calero, Cecilia Ines; Beltrán González, Andrea Natalia; Gasulla, Javier; Alvarez, Silvia; Evelson, Pablo Andres; et al.; Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism; Elsevier; European Journal of Pharmacology; 714; 1-3; 8-2013; 274-280
0014-2999
url http://hdl.handle.net/11336/6601
identifier_str_mv Calero, Cecilia Ines; Beltrán González, Andrea Natalia; Gasulla, Javier; Alvarez, Silvia; Evelson, Pablo Andres; et al.; Quercetin antagonism of GABAAρ1 receptors is prevented by ascorbic acid through a redox-independent mechanism; Elsevier; European Journal of Pharmacology; 714; 1-3; 8-2013; 274-280
0014-2999
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/url/http://www.sciencedirect.com/science/article/pii/S0014299913005669
info:eu-repo/semantics/altIdentifier/doi/
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.ejphar.2013.07.044
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-nd/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-nd/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/msword
application/pdf
application/pdf
application/pdf
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application/pdf
application/pdf
dc.publisher.none.fl_str_mv Elsevier
publisher.none.fl_str_mv Elsevier
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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score 12.993085

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