Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels

Autores
Soria, Leandro Raul; Marrone, Julieta; Calamita, Giuseppe; Marinelli, Raul Alberto
Año de publicación
2013
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Hepatocyte mitochondrial ammonia detoxification via ureagenesis is critical for the prevention of hyperammonemia and hepatic encephalopathy. Aquaporin-8 (AQP8) channels facilitate the membrane transport of ammonia. Because AQP8 is expressed in hepatocyte inner mitochondrial membranes (IMMs), we studied whether mitochondrial AQP8 (mtAQP8) plays a role in ureagenesis from ammonia. Primary cultured rat hepatocytes were transfected with small interfering RNAs (siRNAs) targeting two different regions of the rat AQP8 molecule or with scrambled control siRNA. After 48 hours, the levels of mtAQP8 protein decreased by approximately 80% (P < 0.05) without affecting cell viability. mtAQP8 knockdown cells in the presence of ammonium chloride showed a decrease in ureagenesis of approximately 30% (P < 0.05). Glucagon strongly stimulated ureagenesis in control hepatocytes (+120%, P < 0.05) but induced no significant stimulation in mtAQP8 knockdown cells. Contrarily, mtAQP8 silencing induced no significant change in basal and glucagon-induced ureagenesis when glutamine or alanine was used as a source of nitrogen. Nuclear magnetic resonance studies using 15N-labeled ammonia confirmed that glucagon-induced 15N-labeled urea synthesis was markedly reduced in mtAQP8 knockdown hepatocytes (-90%, P < 0.05). In vivo studies in rats showed that under glucagon-induced ureagenesis, hepatic mtAQP8 protein expression was markedly up-regulated (+160%, P < 0.05). Moreover, transport studies in liver IMM vesicles showed that glucagon increased the diffusional permeability to the ammonia analog [(14) C]methylamine (+80%, P < 0.05).
Fil: Soria, Leandro Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); Argentina
Fil: Marrone, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); Argentina
Fil: Calamita, Giuseppe. Universita degli Studi di Bari Aldo Moro; Italia
Fil: Marinelli, Raul Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); Argentina
Materia
Urea Synthesis
Mitochondrial Ammonia Transport
Aqua-Ammoniaporin
Glucagon
Liver
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:11336/6107

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repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channelsSoria, Leandro RaulMarrone, JulietaCalamita, GiuseppeMarinelli, Raul AlbertoUrea SynthesisMitochondrial Ammonia TransportAqua-AmmoniaporinGlucagonLiverhttps://purl.org/becyt/ford/3.1https://purl.org/becyt/ford/3Hepatocyte mitochondrial ammonia detoxification via ureagenesis is critical for the prevention of hyperammonemia and hepatic encephalopathy. Aquaporin-8 (AQP8) channels facilitate the membrane transport of ammonia. Because AQP8 is expressed in hepatocyte inner mitochondrial membranes (IMMs), we studied whether mitochondrial AQP8 (mtAQP8) plays a role in ureagenesis from ammonia. Primary cultured rat hepatocytes were transfected with small interfering RNAs (siRNAs) targeting two different regions of the rat AQP8 molecule or with scrambled control siRNA. After 48 hours, the levels of mtAQP8 protein decreased by approximately 80% (P < 0.05) without affecting cell viability. mtAQP8 knockdown cells in the presence of ammonium chloride showed a decrease in ureagenesis of approximately 30% (P < 0.05). Glucagon strongly stimulated ureagenesis in control hepatocytes (+120%, P < 0.05) but induced no significant stimulation in mtAQP8 knockdown cells. Contrarily, mtAQP8 silencing induced no significant change in basal and glucagon-induced ureagenesis when glutamine or alanine was used as a source of nitrogen. Nuclear magnetic resonance studies using 15N-labeled ammonia confirmed that glucagon-induced 15N-labeled urea synthesis was markedly reduced in mtAQP8 knockdown hepatocytes (-90%, P < 0.05). In vivo studies in rats showed that under glucagon-induced ureagenesis, hepatic mtAQP8 protein expression was markedly up-regulated (+160%, P < 0.05). Moreover, transport studies in liver IMM vesicles showed that glucagon increased the diffusional permeability to the ammonia analog [(14) C]methylamine (+80%, P < 0.05).Fil: Soria, Leandro Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); ArgentinaFil: Marrone, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); ArgentinaFil: Calamita, Giuseppe. Universita degli Studi di Bari Aldo Moro; ItaliaFil: Marinelli, Raul Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); ArgentinaAmerican Association for the Study of Liver Diseases2013-05info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/6107Soria, Leandro Raul; Marrone, Julieta; Calamita, Giuseppe; Marinelli, Raul Alberto; Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels; American Association for the Study of Liver Diseases; Hepatology (baltimore, Md.); 57; 5; 5-2013; 2061-20710270-9139enginfo:eu-repo/semantics/altIdentifier/url/www.onlinelibrary.wiley.com/doi/10.1002/hep.26236info:eu-repo/semantics/altIdentifier/doi/10.1002/hep.26236info:eu-repo/semantics/altIdentifier/doi/info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:18:55Zoai:ri.conicet.gov.ar:11336/6107instacron: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:34982025-09-29 10:18:55.32CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels
title Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels
spellingShingle Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels
Soria, Leandro Raul
Urea Synthesis
Mitochondrial Ammonia Transport
Aqua-Ammoniaporin
Glucagon
Liver
title_short Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels
title_full Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels
title_fullStr Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels
title_full_unstemmed Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels
title_sort Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels
dc.creator.none.fl_str_mv Soria, Leandro Raul
Marrone, Julieta
Calamita, Giuseppe
Marinelli, Raul Alberto
author Soria, Leandro Raul
author_facet Soria, Leandro Raul
Marrone, Julieta
Calamita, Giuseppe
Marinelli, Raul Alberto
author_role author
author2 Marrone, Julieta
Calamita, Giuseppe
Marinelli, Raul Alberto
author2_role author
author
author
dc.subject.none.fl_str_mv Urea Synthesis
Mitochondrial Ammonia Transport
Aqua-Ammoniaporin
Glucagon
Liver
topic Urea Synthesis
Mitochondrial Ammonia Transport
Aqua-Ammoniaporin
Glucagon
Liver
purl_subject.fl_str_mv https://purl.org/becyt/ford/3.1
https://purl.org/becyt/ford/3
dc.description.none.fl_txt_mv Hepatocyte mitochondrial ammonia detoxification via ureagenesis is critical for the prevention of hyperammonemia and hepatic encephalopathy. Aquaporin-8 (AQP8) channels facilitate the membrane transport of ammonia. Because AQP8 is expressed in hepatocyte inner mitochondrial membranes (IMMs), we studied whether mitochondrial AQP8 (mtAQP8) plays a role in ureagenesis from ammonia. Primary cultured rat hepatocytes were transfected with small interfering RNAs (siRNAs) targeting two different regions of the rat AQP8 molecule or with scrambled control siRNA. After 48 hours, the levels of mtAQP8 protein decreased by approximately 80% (P < 0.05) without affecting cell viability. mtAQP8 knockdown cells in the presence of ammonium chloride showed a decrease in ureagenesis of approximately 30% (P < 0.05). Glucagon strongly stimulated ureagenesis in control hepatocytes (+120%, P < 0.05) but induced no significant stimulation in mtAQP8 knockdown cells. Contrarily, mtAQP8 silencing induced no significant change in basal and glucagon-induced ureagenesis when glutamine or alanine was used as a source of nitrogen. Nuclear magnetic resonance studies using 15N-labeled ammonia confirmed that glucagon-induced 15N-labeled urea synthesis was markedly reduced in mtAQP8 knockdown hepatocytes (-90%, P < 0.05). In vivo studies in rats showed that under glucagon-induced ureagenesis, hepatic mtAQP8 protein expression was markedly up-regulated (+160%, P < 0.05). Moreover, transport studies in liver IMM vesicles showed that glucagon increased the diffusional permeability to the ammonia analog [(14) C]methylamine (+80%, P < 0.05).
Fil: Soria, Leandro Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); Argentina
Fil: Marrone, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); Argentina
Fil: Calamita, Giuseppe. Universita degli Studi di Bari Aldo Moro; Italia
Fil: Marinelli, Raul Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); Argentina
description Hepatocyte mitochondrial ammonia detoxification via ureagenesis is critical for the prevention of hyperammonemia and hepatic encephalopathy. Aquaporin-8 (AQP8) channels facilitate the membrane transport of ammonia. Because AQP8 is expressed in hepatocyte inner mitochondrial membranes (IMMs), we studied whether mitochondrial AQP8 (mtAQP8) plays a role in ureagenesis from ammonia. Primary cultured rat hepatocytes were transfected with small interfering RNAs (siRNAs) targeting two different regions of the rat AQP8 molecule or with scrambled control siRNA. After 48 hours, the levels of mtAQP8 protein decreased by approximately 80% (P < 0.05) without affecting cell viability. mtAQP8 knockdown cells in the presence of ammonium chloride showed a decrease in ureagenesis of approximately 30% (P < 0.05). Glucagon strongly stimulated ureagenesis in control hepatocytes (+120%, P < 0.05) but induced no significant stimulation in mtAQP8 knockdown cells. Contrarily, mtAQP8 silencing induced no significant change in basal and glucagon-induced ureagenesis when glutamine or alanine was used as a source of nitrogen. Nuclear magnetic resonance studies using 15N-labeled ammonia confirmed that glucagon-induced 15N-labeled urea synthesis was markedly reduced in mtAQP8 knockdown hepatocytes (-90%, P < 0.05). In vivo studies in rats showed that under glucagon-induced ureagenesis, hepatic mtAQP8 protein expression was markedly up-regulated (+160%, P < 0.05). Moreover, transport studies in liver IMM vesicles showed that glucagon increased the diffusional permeability to the ammonia analog [(14) C]methylamine (+80%, P < 0.05).
publishDate 2013
dc.date.none.fl_str_mv 2013-05
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/11336/6107
Soria, Leandro Raul; Marrone, Julieta; Calamita, Giuseppe; Marinelli, Raul Alberto; Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels; American Association for the Study of Liver Diseases; Hepatology (baltimore, Md.); 57; 5; 5-2013; 2061-2071
0270-9139
url http://hdl.handle.net/11336/6107
identifier_str_mv Soria, Leandro Raul; Marrone, Julieta; Calamita, Giuseppe; Marinelli, Raul Alberto; Ammonia detoxification via ureagenesis in rat hepatocytes involves mitochondrial aquaporin-8 channels; American Association for the Study of Liver Diseases; Hepatology (baltimore, Md.); 57; 5; 5-2013; 2061-2071
0270-9139
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/url/www.onlinelibrary.wiley.com/doi/10.1002/hep.26236
info:eu-repo/semantics/altIdentifier/doi/10.1002/hep.26236
info:eu-repo/semantics/altIdentifier/doi/
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
application/pdf
dc.publisher.none.fl_str_mv American Association for the Study of Liver Diseases
publisher.none.fl_str_mv American Association for the Study of Liver Diseases
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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