Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats

Autores
Lazcano, Iván; Cabral, Agustina Soledad; Uribe, Rosa María; Jaimes Hoy, Lorraine; Perello, Mario; Joseph Bravo, Patricia; Sánchez-Jaramillo, Edith; Charli, Jean Louis
Año de publicación
2015
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Fasting down-regulates the hypothalamus-pituitary-thyroid (HPT) axis activity through a reduction of TRH synthesis in neurons of the parvocellular paraventricular nucleus of the hypothalamus (PVN). These TRH neurons project to the median eminence (ME), where TRH terminals are close to the cytoplasmic extensions of β2 tanycytes. Tanycytes express pyroglutamyl peptidase II (PPII), the TRH-degrading ectoenzyme that controls the amount of TRH that reaches the anterior pituitary. We tested the hypothesis that regulation of ME PPII activity is another mechanism by which fasting affects the activity of the HPT axis. Semiquantitative in situ hybridization histochemistry data indicated that PPII and deiodinase 2 mRNA levels increased in tanycytes after 48 hours of fasting. This increase was transitory, followed by an increase of PPII activity in the ME, and a partial reversion of the reduction in PVN pro-TRH mRNA levels and the number of TRH neurons detected by immunohistochemistry. In fed animals, adrenalectomy and corticosterone treatment did not change ME PPII activity 72 hours later. Methimazole-induced hypothyroidism produced a profound drop in tanycytes PPII mRNA levels, which was reverted by 3 days of treatment with T4. The activity of thyroliberinase, the serum isoform of PPII, was increased at most fasting time points studied. We conclude that delayed increases in both the ME PPII as well as the thyroliberinase activities in fasted male rats may facilitate the maintenance of the deep down-regulation of the HPT axis function, despite a partial reactivation of TRH expression in the PVN.
Fil: Lazcano, Iván. Universidad Nacional Autónoma de México; México
Fil: Cabral, Agustina Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina
Fil: Uribe, Rosa María. Universidad Nacional Autónoma de México; México
Fil: Jaimes Hoy, Lorraine. Universidad Nacional Autónoma de México; México
Fil: Perello, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina
Fil: Joseph Bravo, Patricia. Universidad Nacional Autónoma de México; México
Fil: Sánchez-Jaramillo, Edith. Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz; México
Fil: Charli, Jean Louis. Universidad Nacional Autónoma de México; México
Materia
Thyroid
Trh
Tsh
Thyroid
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/53387
Acceder
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oai_identifier_str oai:ri.conicet.gov.ar:11336/53387
network_acronym_str CONICETDig
repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult ratsLazcano, IvánCabral, Agustina SoledadUribe, Rosa MaríaJaimes Hoy, LorrainePerello, MarioJoseph Bravo, PatriciaSánchez-Jaramillo, EdithCharli, Jean LouisThyroidTrhTshThyroidhttps://purl.org/becyt/ford/3.1https://purl.org/becyt/ford/3Fasting down-regulates the hypothalamus-pituitary-thyroid (HPT) axis activity through a reduction of TRH synthesis in neurons of the parvocellular paraventricular nucleus of the hypothalamus (PVN). These TRH neurons project to the median eminence (ME), where TRH terminals are close to the cytoplasmic extensions of β2 tanycytes. Tanycytes express pyroglutamyl peptidase II (PPII), the TRH-degrading ectoenzyme that controls the amount of TRH that reaches the anterior pituitary. We tested the hypothesis that regulation of ME PPII activity is another mechanism by which fasting affects the activity of the HPT axis. Semiquantitative in situ hybridization histochemistry data indicated that PPII and deiodinase 2 mRNA levels increased in tanycytes after 48 hours of fasting. This increase was transitory, followed by an increase of PPII activity in the ME, and a partial reversion of the reduction in PVN pro-TRH mRNA levels and the number of TRH neurons detected by immunohistochemistry. In fed animals, adrenalectomy and corticosterone treatment did not change ME PPII activity 72 hours later. Methimazole-induced hypothyroidism produced a profound drop in tanycytes PPII mRNA levels, which was reverted by 3 days of treatment with T4. The activity of thyroliberinase, the serum isoform of PPII, was increased at most fasting time points studied. We conclude that delayed increases in both the ME PPII as well as the thyroliberinase activities in fasted male rats may facilitate the maintenance of the deep down-regulation of the HPT axis function, despite a partial reactivation of TRH expression in the PVN.Fil: Lazcano, Iván. Universidad Nacional Autónoma de México; MéxicoFil: Cabral, Agustina Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Uribe, Rosa María. Universidad Nacional Autónoma de México; MéxicoFil: Jaimes Hoy, Lorraine. Universidad Nacional Autónoma de México; MéxicoFil: Perello, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Joseph Bravo, Patricia. Universidad Nacional Autónoma de México; MéxicoFil: Sánchez-Jaramillo, Edith. Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz; MéxicoFil: Charli, Jean Louis. Universidad Nacional Autónoma de México; MéxicoEndocrine Society2015-07info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/53387Lazcano, Iván; Cabral, Agustina Soledad; Uribe, Rosa María; Jaimes Hoy, Lorraine; Perello, Mario; et al.; Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats; Endocrine Society; Endocrinology; 156; 7; 7-2015; 2713-27230013-7227CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1210/en.2014-1885info:eu-repo/semantics/altIdentifier/url/https://academic.oup.com/endo/article/156/7/2713/2423409info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-03T09:48:19Zoai:ri.conicet.gov.ar:11336/53387instacron: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:34982025-09-03 09:48:19.457CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats
title Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats
spellingShingle Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats
Lazcano, Iván
Thyroid
Trh
Tsh
Thyroid
title_short Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats
title_full Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats
title_fullStr Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats
title_full_unstemmed Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats
title_sort Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats
dc.creator.none.fl_str_mv Lazcano, Iván
Cabral, Agustina Soledad
Uribe, Rosa María
Jaimes Hoy, Lorraine
Perello, Mario
Joseph Bravo, Patricia
Sánchez-Jaramillo, Edith
Charli, Jean Louis
author Lazcano, Iván
author_facet Lazcano, Iván
Cabral, Agustina Soledad
Uribe, Rosa María
Jaimes Hoy, Lorraine
Perello, Mario
Joseph Bravo, Patricia
Sánchez-Jaramillo, Edith
Charli, Jean Louis
author_role author
author2 Cabral, Agustina Soledad
Uribe, Rosa María
Jaimes Hoy, Lorraine
Perello, Mario
Joseph Bravo, Patricia
Sánchez-Jaramillo, Edith
Charli, Jean Louis
author2_role author
author
author
author
author
author
author
dc.subject.none.fl_str_mv Thyroid
Trh
Tsh
Thyroid
topic Thyroid
Trh
Tsh
Thyroid
purl_subject.fl_str_mv https://purl.org/becyt/ford/3.1
https://purl.org/becyt/ford/3
dc.description.none.fl_txt_mv Fasting down-regulates the hypothalamus-pituitary-thyroid (HPT) axis activity through a reduction of TRH synthesis in neurons of the parvocellular paraventricular nucleus of the hypothalamus (PVN). These TRH neurons project to the median eminence (ME), where TRH terminals are close to the cytoplasmic extensions of β2 tanycytes. Tanycytes express pyroglutamyl peptidase II (PPII), the TRH-degrading ectoenzyme that controls the amount of TRH that reaches the anterior pituitary. We tested the hypothesis that regulation of ME PPII activity is another mechanism by which fasting affects the activity of the HPT axis. Semiquantitative in situ hybridization histochemistry data indicated that PPII and deiodinase 2 mRNA levels increased in tanycytes after 48 hours of fasting. This increase was transitory, followed by an increase of PPII activity in the ME, and a partial reversion of the reduction in PVN pro-TRH mRNA levels and the number of TRH neurons detected by immunohistochemistry. In fed animals, adrenalectomy and corticosterone treatment did not change ME PPII activity 72 hours later. Methimazole-induced hypothyroidism produced a profound drop in tanycytes PPII mRNA levels, which was reverted by 3 days of treatment with T4. The activity of thyroliberinase, the serum isoform of PPII, was increased at most fasting time points studied. We conclude that delayed increases in both the ME PPII as well as the thyroliberinase activities in fasted male rats may facilitate the maintenance of the deep down-regulation of the HPT axis function, despite a partial reactivation of TRH expression in the PVN.
Fil: Lazcano, Iván. Universidad Nacional Autónoma de México; México
Fil: Cabral, Agustina Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina
Fil: Uribe, Rosa María. Universidad Nacional Autónoma de México; México
Fil: Jaimes Hoy, Lorraine. Universidad Nacional Autónoma de México; México
Fil: Perello, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina
Fil: Joseph Bravo, Patricia. Universidad Nacional Autónoma de México; México
Fil: Sánchez-Jaramillo, Edith. Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz; México
Fil: Charli, Jean Louis. Universidad Nacional Autónoma de México; México
description Fasting down-regulates the hypothalamus-pituitary-thyroid (HPT) axis activity through a reduction of TRH synthesis in neurons of the parvocellular paraventricular nucleus of the hypothalamus (PVN). These TRH neurons project to the median eminence (ME), where TRH terminals are close to the cytoplasmic extensions of β2 tanycytes. Tanycytes express pyroglutamyl peptidase II (PPII), the TRH-degrading ectoenzyme that controls the amount of TRH that reaches the anterior pituitary. We tested the hypothesis that regulation of ME PPII activity is another mechanism by which fasting affects the activity of the HPT axis. Semiquantitative in situ hybridization histochemistry data indicated that PPII and deiodinase 2 mRNA levels increased in tanycytes after 48 hours of fasting. This increase was transitory, followed by an increase of PPII activity in the ME, and a partial reversion of the reduction in PVN pro-TRH mRNA levels and the number of TRH neurons detected by immunohistochemistry. In fed animals, adrenalectomy and corticosterone treatment did not change ME PPII activity 72 hours later. Methimazole-induced hypothyroidism produced a profound drop in tanycytes PPII mRNA levels, which was reverted by 3 days of treatment with T4. The activity of thyroliberinase, the serum isoform of PPII, was increased at most fasting time points studied. We conclude that delayed increases in both the ME PPII as well as the thyroliberinase activities in fasted male rats may facilitate the maintenance of the deep down-regulation of the HPT axis function, despite a partial reactivation of TRH expression in the PVN.
publishDate 2015
dc.date.none.fl_str_mv 2015-07
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/11336/53387
Lazcano, Iván; Cabral, Agustina Soledad; Uribe, Rosa María; Jaimes Hoy, Lorraine; Perello, Mario; et al.; Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats; Endocrine Society; Endocrinology; 156; 7; 7-2015; 2713-2723
0013-7227
CONICET Digital
CONICET
url http://hdl.handle.net/11336/53387
identifier_str_mv Lazcano, Iván; Cabral, Agustina Soledad; Uribe, Rosa María; Jaimes Hoy, Lorraine; Perello, Mario; et al.; Fasting enhances pyroglutamyl peptidase II activity in tanycytes of the mediobasal hypothalamus of male adult rats; Endocrine Society; Endocrinology; 156; 7; 7-2015; 2713-2723
0013-7227
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1210/en.2014-1885
info:eu-repo/semantics/altIdentifier/url/https://academic.oup.com/endo/article/156/7/2713/2423409
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
application/pdf
dc.publisher.none.fl_str_mv Endocrine Society
publisher.none.fl_str_mv Endocrine Society
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
_version_ 1842268917650685952
score 13.13397

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