Metabolic insights from a GHSR-A203E mutant mouse model

Autores
Torz, Lola J.; Osborne Lawrence, Sherri; Rodriguez, Juan; He, Zhenyan; Cornejo, María Paula; Mustafá, Emilio Román; Jin, Chunyu; Petersen, Natalia; Hedegaard, Morten A.; Nybo, Maja; Martínez Damonte, Valentina; Metzger, Nathan P.; Mani, Bharath K.; Williams, Kevin W.; Raingo, Jesica; Perello, Mario; Holst, Birgitte; Zigman, Jeffrey M.
Año de publicación
2020
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Objective: Binding of ghrelin to its receptor, growth hormone secretagogue receptor (GHSR), stimulates GH release, induces eating, and increases blood glucose. These processes may also be influenced by constitutive (ghrelin-independent) GHSR activity, as suggested by findings in short people with naturally occurring GHSR-A204E mutations and reduced food intake and blood glucose in rodents administered GHSR inverse agonists, both of which impair constitutive GHSR activity. In this study, we aimed to more fully determine the physiologic relevance of constitutive GHSR activity. Methods: We generated mice with a GHSR mutation that replaces alanine at position 203 with glutamate (GHSR-A203E), which corresponds to the previously described human GHSR-A204E mutation, and used them to conduct ex vivo neuronal electrophysiology and in vivo metabolic assessments. We also measured signaling within COS-7 and HEK293T cells transfected with wild-type GHSR (GHSR-WT) or GHSR-A203E constructs. Results: In COS-7 cells, GHSR-A203E resulted in lower baseline IP3 accumulation than GHSR-WT; ghrelin-induced IP3 accumulation was observed in both constructs. In HEK293T cells co-transfected with voltage-gated CaV2.2 calcium channel complex, GHSR-A203E had no effect on basal CaV2.2 current density while GHSR-WT did; both GHSR-A203E and GHSR-WT inhibited CaV2.2 current in the presence of ghrelin. In cultured hypothalamic neurons from GHSR-A203E and GHSR-deficient mice, native calcium currents were greater than those in neurons from wild-type mice; ghrelin inhibited calcium currents in cultured hypothalamic neurons from both GHSR-A203E and wild-type mice. In brain slices, resting membrane potentials of arcuate NPY neurons from GHSR-A203E mice were hyperpolarized compared to those from wild-type mice; the same percentage of arcuate NPY neurons from GHSR-A203E and wild-type mice depolarized upon ghrelin exposure. The GHSR-A203E mutation did not significantly affect body weight, body length, or femur length in the first ∼6 months of life, yet these parameters were lower in GHSR-A203E mice after 1 year of age. During a 7-d 60% caloric restriction regimen, GHSR-A203E mice lacked the usual marked rise in plasma GH and demonstrated an exaggerated drop in blood glucose. Administered ghrelin also exhibited reduced orexigenic and GH secretagogue efficacies in GHSR-A203E mice. Conclusions: Our data suggest that the A203E mutation ablates constitutive GHSR activity and that constitutive GHSR activity contributes to the native depolarizing conductance of GHSR-expressing arcuate NPY neurons. Although the A203E mutation does not block ghrelin-evoked signaling as assessed using in vitro and ex vivo models, GHSR-A203E mice lack the usual acute food intake response to administered ghrelin in vivo. The GHSR-A203E mutation also blunts GH release, and in aged mice leads to reduced body length and femur length, which are consistent with the short stature of human carriers of the GHSR-A204E mutation.
Fil: Torz, Lola J.. Universidad de Copenhagen; Dinamarca
Fil: Osborne Lawrence, Sherri. Ut Southwestern Medical Center; Estados Unidos
Fil: Rodriguez, Juan. Ut Southwestern Medical Center; Estados Unidos
Fil: He, Zhenyan. Ut Southwestern Medical Center; Estados Unidos
Fil: Cornejo, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina
Fil: Mustafá, Emilio Román. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina
Fil: Jin, Chunyu. Universidad de Copenhagen; Dinamarca
Fil: Petersen, Natalia. Universidad de Copenhagen; Dinamarca
Fil: Hedegaard, Morten A.. Universidad de Copenhagen; Dinamarca
Fil: Nybo, Maja. Universidad de Copenhagen; Dinamarca
Fil: Martínez Damonte, Valentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina
Fil: Metzger, Nathan P.. Ut Southwestern Medical Center; Estados Unidos
Fil: Mani, Bharath K.. Ut Southwestern Medical Center; Estados Unidos
Fil: Williams, Kevin W.. Ut Southwestern Medical Center; Estados Unidos
Fil: Raingo, Jesica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina
Fil: Perello, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina
Fil: Holst, Birgitte. Universidad de Copenhagen; Dinamarca
Fil: Zigman, Jeffrey M.. Ut Southwestern Medical Center; Estados Unidos
Materia
CONSTITUTIVE ACTIVITY
GH
GHRELIN
GROWTH HORMONE
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:11336/180728
Acceder
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repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Metabolic insights from a GHSR-A203E mutant mouse modelTorz, Lola J.Osborne Lawrence, SherriRodriguez, JuanHe, ZhenyanCornejo, María PaulaMustafá, Emilio RománJin, ChunyuPetersen, NataliaHedegaard, Morten A.Nybo, MajaMartínez Damonte, ValentinaMetzger, Nathan P.Mani, Bharath K.Williams, Kevin W.Raingo, JesicaPerello, MarioHolst, BirgitteZigman, Jeffrey M.CONSTITUTIVE ACTIVITYGHGHRELINGROWTH HORMONEhttps://purl.org/becyt/ford/3.1https://purl.org/becyt/ford/3Objective: Binding of ghrelin to its receptor, growth hormone secretagogue receptor (GHSR), stimulates GH release, induces eating, and increases blood glucose. These processes may also be influenced by constitutive (ghrelin-independent) GHSR activity, as suggested by findings in short people with naturally occurring GHSR-A204E mutations and reduced food intake and blood glucose in rodents administered GHSR inverse agonists, both of which impair constitutive GHSR activity. In this study, we aimed to more fully determine the physiologic relevance of constitutive GHSR activity. Methods: We generated mice with a GHSR mutation that replaces alanine at position 203 with glutamate (GHSR-A203E), which corresponds to the previously described human GHSR-A204E mutation, and used them to conduct ex vivo neuronal electrophysiology and in vivo metabolic assessments. We also measured signaling within COS-7 and HEK293T cells transfected with wild-type GHSR (GHSR-WT) or GHSR-A203E constructs. Results: In COS-7 cells, GHSR-A203E resulted in lower baseline IP3 accumulation than GHSR-WT; ghrelin-induced IP3 accumulation was observed in both constructs. In HEK293T cells co-transfected with voltage-gated CaV2.2 calcium channel complex, GHSR-A203E had no effect on basal CaV2.2 current density while GHSR-WT did; both GHSR-A203E and GHSR-WT inhibited CaV2.2 current in the presence of ghrelin. In cultured hypothalamic neurons from GHSR-A203E and GHSR-deficient mice, native calcium currents were greater than those in neurons from wild-type mice; ghrelin inhibited calcium currents in cultured hypothalamic neurons from both GHSR-A203E and wild-type mice. In brain slices, resting membrane potentials of arcuate NPY neurons from GHSR-A203E mice were hyperpolarized compared to those from wild-type mice; the same percentage of arcuate NPY neurons from GHSR-A203E and wild-type mice depolarized upon ghrelin exposure. The GHSR-A203E mutation did not significantly affect body weight, body length, or femur length in the first ∼6 months of life, yet these parameters were lower in GHSR-A203E mice after 1 year of age. During a 7-d 60% caloric restriction regimen, GHSR-A203E mice lacked the usual marked rise in plasma GH and demonstrated an exaggerated drop in blood glucose. Administered ghrelin also exhibited reduced orexigenic and GH secretagogue efficacies in GHSR-A203E mice. Conclusions: Our data suggest that the A203E mutation ablates constitutive GHSR activity and that constitutive GHSR activity contributes to the native depolarizing conductance of GHSR-expressing arcuate NPY neurons. Although the A203E mutation does not block ghrelin-evoked signaling as assessed using in vitro and ex vivo models, GHSR-A203E mice lack the usual acute food intake response to administered ghrelin in vivo. The GHSR-A203E mutation also blunts GH release, and in aged mice leads to reduced body length and femur length, which are consistent with the short stature of human carriers of the GHSR-A204E mutation.Fil: Torz, Lola J.. Universidad de Copenhagen; DinamarcaFil: Osborne Lawrence, Sherri. Ut Southwestern Medical Center; Estados UnidosFil: Rodriguez, Juan. Ut Southwestern Medical Center; Estados UnidosFil: He, Zhenyan. Ut Southwestern Medical Center; Estados UnidosFil: Cornejo, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Mustafá, Emilio Román. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Jin, Chunyu. Universidad de Copenhagen; DinamarcaFil: Petersen, Natalia. Universidad de Copenhagen; DinamarcaFil: Hedegaard, Morten A.. Universidad de Copenhagen; DinamarcaFil: Nybo, Maja. Universidad de Copenhagen; DinamarcaFil: Martínez Damonte, Valentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Metzger, Nathan P.. Ut Southwestern Medical Center; Estados UnidosFil: Mani, Bharath K.. Ut Southwestern Medical Center; Estados UnidosFil: Williams, Kevin W.. Ut Southwestern Medical Center; Estados UnidosFil: Raingo, Jesica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Perello, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Holst, Birgitte. Universidad de Copenhagen; DinamarcaFil: Zigman, Jeffrey M.. Ut Southwestern Medical Center; Estados UnidosElsevier2020-04info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/180728Torz, Lola J.; Osborne Lawrence, Sherri; Rodriguez, Juan; He, Zhenyan; Cornejo, María Paula; et al.; Metabolic insights from a GHSR-A203E mutant mouse model; Elsevier; Molecular Metabolism; 39; 4-2020; 1-332212-8778CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/url/https://linkinghub.elsevier.com/retrieve/pii/S2212877820300788info:eu-repo/semantics/altIdentifier/doi/10.1016/j.molmet.2020.101004info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-nd/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:16:45Zoai:ri.conicet.gov.ar:11336/180728instacron: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 10:16:45.671CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Metabolic insights from a GHSR-A203E mutant mouse model
title Metabolic insights from a GHSR-A203E mutant mouse model
spellingShingle Metabolic insights from a GHSR-A203E mutant mouse model
Torz, Lola J.
CONSTITUTIVE ACTIVITY
GH
GHRELIN
GROWTH HORMONE
title_short Metabolic insights from a GHSR-A203E mutant mouse model
title_full Metabolic insights from a GHSR-A203E mutant mouse model
title_fullStr Metabolic insights from a GHSR-A203E mutant mouse model
title_full_unstemmed Metabolic insights from a GHSR-A203E mutant mouse model
title_sort Metabolic insights from a GHSR-A203E mutant mouse model
dc.creator.none.fl_str_mv Torz, Lola J.
Osborne Lawrence, Sherri
Rodriguez, Juan
He, Zhenyan
Cornejo, María Paula
Mustafá, Emilio Román
Jin, Chunyu
Petersen, Natalia
Hedegaard, Morten A.
Nybo, Maja
Martínez Damonte, Valentina
Metzger, Nathan P.
Mani, Bharath K.
Williams, Kevin W.
Raingo, Jesica
Perello, Mario
Holst, Birgitte
Zigman, Jeffrey M.
author Torz, Lola J.
author_facet Torz, Lola J.
Osborne Lawrence, Sherri
Rodriguez, Juan
He, Zhenyan
Cornejo, María Paula
Mustafá, Emilio Román
Jin, Chunyu
Petersen, Natalia
Hedegaard, Morten A.
Nybo, Maja
Martínez Damonte, Valentina
Metzger, Nathan P.
Mani, Bharath K.
Williams, Kevin W.
Raingo, Jesica
Perello, Mario
Holst, Birgitte
Zigman, Jeffrey M.
author_role author
author2 Osborne Lawrence, Sherri
Rodriguez, Juan
He, Zhenyan
Cornejo, María Paula
Mustafá, Emilio Román
Jin, Chunyu
Petersen, Natalia
Hedegaard, Morten A.
Nybo, Maja
Martínez Damonte, Valentina
Metzger, Nathan P.
Mani, Bharath K.
Williams, Kevin W.
Raingo, Jesica
Perello, Mario
Holst, Birgitte
Zigman, Jeffrey M.
author2_role author
author
author
author
author
author
author
author
author
author
author
author
author
author
author
author
author
dc.subject.none.fl_str_mv CONSTITUTIVE ACTIVITY
GH
GHRELIN
GROWTH HORMONE
topic CONSTITUTIVE ACTIVITY
GH
GHRELIN
GROWTH HORMONE
purl_subject.fl_str_mv https://purl.org/becyt/ford/3.1
https://purl.org/becyt/ford/3
dc.description.none.fl_txt_mv Objective: Binding of ghrelin to its receptor, growth hormone secretagogue receptor (GHSR), stimulates GH release, induces eating, and increases blood glucose. These processes may also be influenced by constitutive (ghrelin-independent) GHSR activity, as suggested by findings in short people with naturally occurring GHSR-A204E mutations and reduced food intake and blood glucose in rodents administered GHSR inverse agonists, both of which impair constitutive GHSR activity. In this study, we aimed to more fully determine the physiologic relevance of constitutive GHSR activity. Methods: We generated mice with a GHSR mutation that replaces alanine at position 203 with glutamate (GHSR-A203E), which corresponds to the previously described human GHSR-A204E mutation, and used them to conduct ex vivo neuronal electrophysiology and in vivo metabolic assessments. We also measured signaling within COS-7 and HEK293T cells transfected with wild-type GHSR (GHSR-WT) or GHSR-A203E constructs. Results: In COS-7 cells, GHSR-A203E resulted in lower baseline IP3 accumulation than GHSR-WT; ghrelin-induced IP3 accumulation was observed in both constructs. In HEK293T cells co-transfected with voltage-gated CaV2.2 calcium channel complex, GHSR-A203E had no effect on basal CaV2.2 current density while GHSR-WT did; both GHSR-A203E and GHSR-WT inhibited CaV2.2 current in the presence of ghrelin. In cultured hypothalamic neurons from GHSR-A203E and GHSR-deficient mice, native calcium currents were greater than those in neurons from wild-type mice; ghrelin inhibited calcium currents in cultured hypothalamic neurons from both GHSR-A203E and wild-type mice. In brain slices, resting membrane potentials of arcuate NPY neurons from GHSR-A203E mice were hyperpolarized compared to those from wild-type mice; the same percentage of arcuate NPY neurons from GHSR-A203E and wild-type mice depolarized upon ghrelin exposure. The GHSR-A203E mutation did not significantly affect body weight, body length, or femur length in the first ∼6 months of life, yet these parameters were lower in GHSR-A203E mice after 1 year of age. During a 7-d 60% caloric restriction regimen, GHSR-A203E mice lacked the usual marked rise in plasma GH and demonstrated an exaggerated drop in blood glucose. Administered ghrelin also exhibited reduced orexigenic and GH secretagogue efficacies in GHSR-A203E mice. Conclusions: Our data suggest that the A203E mutation ablates constitutive GHSR activity and that constitutive GHSR activity contributes to the native depolarizing conductance of GHSR-expressing arcuate NPY neurons. Although the A203E mutation does not block ghrelin-evoked signaling as assessed using in vitro and ex vivo models, GHSR-A203E mice lack the usual acute food intake response to administered ghrelin in vivo. The GHSR-A203E mutation also blunts GH release, and in aged mice leads to reduced body length and femur length, which are consistent with the short stature of human carriers of the GHSR-A204E mutation.
Fil: Torz, Lola J.. Universidad de Copenhagen; Dinamarca
Fil: Osborne Lawrence, Sherri. Ut Southwestern Medical Center; Estados Unidos
Fil: Rodriguez, Juan. Ut Southwestern Medical Center; Estados Unidos
Fil: He, Zhenyan. Ut Southwestern Medical Center; Estados Unidos
Fil: Cornejo, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina
Fil: Mustafá, Emilio Román. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina
Fil: Jin, Chunyu. Universidad de Copenhagen; Dinamarca
Fil: Petersen, Natalia. Universidad de Copenhagen; Dinamarca
Fil: Hedegaard, Morten A.. Universidad de Copenhagen; Dinamarca
Fil: Nybo, Maja. Universidad de Copenhagen; Dinamarca
Fil: Martínez Damonte, Valentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina
Fil: Metzger, Nathan P.. Ut Southwestern Medical Center; Estados Unidos
Fil: Mani, Bharath K.. Ut Southwestern Medical Center; Estados Unidos
Fil: Williams, Kevin W.. Ut Southwestern Medical Center; Estados Unidos
Fil: Raingo, Jesica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina
Fil: Perello, Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina
Fil: Holst, Birgitte. Universidad de Copenhagen; Dinamarca
Fil: Zigman, Jeffrey M.. Ut Southwestern Medical Center; Estados Unidos
description Objective: Binding of ghrelin to its receptor, growth hormone secretagogue receptor (GHSR), stimulates GH release, induces eating, and increases blood glucose. These processes may also be influenced by constitutive (ghrelin-independent) GHSR activity, as suggested by findings in short people with naturally occurring GHSR-A204E mutations and reduced food intake and blood glucose in rodents administered GHSR inverse agonists, both of which impair constitutive GHSR activity. In this study, we aimed to more fully determine the physiologic relevance of constitutive GHSR activity. Methods: We generated mice with a GHSR mutation that replaces alanine at position 203 with glutamate (GHSR-A203E), which corresponds to the previously described human GHSR-A204E mutation, and used them to conduct ex vivo neuronal electrophysiology and in vivo metabolic assessments. We also measured signaling within COS-7 and HEK293T cells transfected with wild-type GHSR (GHSR-WT) or GHSR-A203E constructs. Results: In COS-7 cells, GHSR-A203E resulted in lower baseline IP3 accumulation than GHSR-WT; ghrelin-induced IP3 accumulation was observed in both constructs. In HEK293T cells co-transfected with voltage-gated CaV2.2 calcium channel complex, GHSR-A203E had no effect on basal CaV2.2 current density while GHSR-WT did; both GHSR-A203E and GHSR-WT inhibited CaV2.2 current in the presence of ghrelin. In cultured hypothalamic neurons from GHSR-A203E and GHSR-deficient mice, native calcium currents were greater than those in neurons from wild-type mice; ghrelin inhibited calcium currents in cultured hypothalamic neurons from both GHSR-A203E and wild-type mice. In brain slices, resting membrane potentials of arcuate NPY neurons from GHSR-A203E mice were hyperpolarized compared to those from wild-type mice; the same percentage of arcuate NPY neurons from GHSR-A203E and wild-type mice depolarized upon ghrelin exposure. The GHSR-A203E mutation did not significantly affect body weight, body length, or femur length in the first ∼6 months of life, yet these parameters were lower in GHSR-A203E mice after 1 year of age. During a 7-d 60% caloric restriction regimen, GHSR-A203E mice lacked the usual marked rise in plasma GH and demonstrated an exaggerated drop in blood glucose. Administered ghrelin also exhibited reduced orexigenic and GH secretagogue efficacies in GHSR-A203E mice. Conclusions: Our data suggest that the A203E mutation ablates constitutive GHSR activity and that constitutive GHSR activity contributes to the native depolarizing conductance of GHSR-expressing arcuate NPY neurons. Although the A203E mutation does not block ghrelin-evoked signaling as assessed using in vitro and ex vivo models, GHSR-A203E mice lack the usual acute food intake response to administered ghrelin in vivo. The GHSR-A203E mutation also blunts GH release, and in aged mice leads to reduced body length and femur length, which are consistent with the short stature of human carriers of the GHSR-A204E mutation.
publishDate 2020
dc.date.none.fl_str_mv 2020-04
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/11336/180728
Torz, Lola J.; Osborne Lawrence, Sherri; Rodriguez, Juan; He, Zhenyan; Cornejo, María Paula; et al.; Metabolic insights from a GHSR-A203E mutant mouse model; Elsevier; Molecular Metabolism; 39; 4-2020; 1-33
2212-8778
CONICET Digital
CONICET
url http://hdl.handle.net/11336/180728
identifier_str_mv Torz, Lola J.; Osborne Lawrence, Sherri; Rodriguez, Juan; He, Zhenyan; Cornejo, María Paula; et al.; Metabolic insights from a GHSR-A203E mutant mouse model; Elsevier; Molecular Metabolism; 39; 4-2020; 1-33
2212-8778
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/url/https://linkinghub.elsevier.com/retrieve/pii/S2212877820300788
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.molmet.2020.101004
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/pdf
dc.publisher.none.fl_str_mv Elsevier
publisher.none.fl_str_mv Elsevier
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
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reponame_str CONICET Digital (CONICET)
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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 13.070432

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