Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished rats
Autor(a) principal: | |
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Data de Publicação: | 2009 |
Outros Autores: | , , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1590/S0100-879X2009001000010 http://hdl.handle.net/11449/8343 |
Resumo: | A low-protein diet leads to functional and structural pancreatic islet alterations, including islet hypotrophy. Insulin-signaling pathways are involved in several adaptive responses by pancreatic islets. We determined the levels of some insulin-signaling proteins related to pancreatic islet function and growth in malnourished rats. Adult male Wistar rats (N = 20 per group) were fed a 17% protein (normal-protein diet; NP) or 6% protein (low-protein diet; LP), for 8 weeks. At the end of this period, blood glucose and serum insulin and albumin levels were measured. The morphometric parameters of the endocrine pancreas and the content of some proteins in islet lysates were determined. The β-cell mass was significantly reduced (≅65%) in normoglycemic but hypoinsulinemic LP rats compared to NP rats. Associated with these alterations, a significant 30% reduction in insulin receptor substrate-1 and a 70% increase in insulin receptor substrate-2 protein content were observed in LP islets compared to NP islets. The phosphorylated serine-threonine protein kinase (pAkt)/Akt protein ratio was similar in LP and NP islets. The phosphorylated forkhead-O1 (pFoxO1)/FoxO1 protein ratio was decreased by 43% in LP islets compared to NP islets (P < 0.05). Finally, the ratio of phosphorylated-extracellular signal-related kinase 1/2 (pErk1/2) to total Erk1/2 protein levels was decreased by 71% in LP islets compared to NP islets (P < 0.05). Therefore, the reduced β-cell mass observed in LP rats is associated with the reduction of phosphorylation in mitogenic-related signals, FoxO1 and Erk proteins. The cause/effect basis of this association remains to be determined. |
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Repositório Institucional da UNESP |
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Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished ratsβ-cell massInsulin signalingLow-protein dietPancreatic isletsProtein phosphorylationA low-protein diet leads to functional and structural pancreatic islet alterations, including islet hypotrophy. Insulin-signaling pathways are involved in several adaptive responses by pancreatic islets. We determined the levels of some insulin-signaling proteins related to pancreatic islet function and growth in malnourished rats. Adult male Wistar rats (N = 20 per group) were fed a 17% protein (normal-protein diet; NP) or 6% protein (low-protein diet; LP), for 8 weeks. At the end of this period, blood glucose and serum insulin and albumin levels were measured. The morphometric parameters of the endocrine pancreas and the content of some proteins in islet lysates were determined. The β-cell mass was significantly reduced (≅65%) in normoglycemic but hypoinsulinemic LP rats compared to NP rats. Associated with these alterations, a significant 30% reduction in insulin receptor substrate-1 and a 70% increase in insulin receptor substrate-2 protein content were observed in LP islets compared to NP islets. The phosphorylated serine-threonine protein kinase (pAkt)/Akt protein ratio was similar in LP and NP islets. The phosphorylated forkhead-O1 (pFoxO1)/FoxO1 protein ratio was decreased by 43% in LP islets compared to NP islets (P < 0.05). Finally, the ratio of phosphorylated-extracellular signal-related kinase 1/2 (pErk1/2) to total Erk1/2 protein levels was decreased by 71% in LP islets compared to NP islets (P < 0.05). Therefore, the reduced β-cell mass observed in LP rats is associated with the reduction of phosphorylation in mitogenic-related signals, FoxO1 and Erk proteins. The cause/effect basis of this association remains to be determined.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Estadual Paulista Faculdade de Ciências Departamento de Educação FísicaUniversidade Estadual de Campinas Instituto de Biologia Biologia Celular e FisiologiaUniversidade de São Paulo Faculdade de Odontologia de Bauru Departamento de Ciências BiológicasUniversidade Estadual Paulista Faculdade de Ciências Departamento de Educação FísicaFAPESP: 02/04310-4FAPESP: 04/11684-9FAPESP: 03/10829-0Associação Brasileira de Divulgação Científica (ABRADIC)Universidade Estadual Paulista (Unesp)Universidade Estadual de Campinas (UNICAMP)Universidade de São Paulo (USP)Rafacho, A. [UNESP]Giozzet, V. A. G.Boschero, A. C.Abrantes, J. L. F.Cestari, T. M.Carneiro, E. M.Bosqueiro, José Roberto [UNESP]2014-05-20T13:26:04Z2014-05-20T13:26:04Z2009-10-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article935-941application/pdfhttp://dx.doi.org/10.1590/S0100-879X2009001000010Brazilian Journal of Medical and Biological Research. Associação Brasileira de Divulgação Científica, v. 42, n. 10, p. 935-941, 2009.0100-879Xhttp://hdl.handle.net/11449/834310.1590/S0100-879X2009001000010S0100-879X2009001000010WOS:000270233400010S0100-879X2009001000010.pdf2423477869556138SciELOreponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengBrazilian Journal of Medical and Biological Research1.492info:eu-repo/semantics/openAccess2024-04-24T18:53:32Zoai:repositorio.unesp.br:11449/8343Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-04-24T18:53:32Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished rats |
title |
Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished rats |
spellingShingle |
Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished rats Rafacho, A. [UNESP] β-cell mass Insulin signaling Low-protein diet Pancreatic islets Protein phosphorylation |
title_short |
Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished rats |
title_full |
Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished rats |
title_fullStr |
Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished rats |
title_full_unstemmed |
Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished rats |
title_sort |
Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished rats |
author |
Rafacho, A. [UNESP] |
author_facet |
Rafacho, A. [UNESP] Giozzet, V. A. G. Boschero, A. C. Abrantes, J. L. F. Cestari, T. M. Carneiro, E. M. Bosqueiro, José Roberto [UNESP] |
author_role |
author |
author2 |
Giozzet, V. A. G. Boschero, A. C. Abrantes, J. L. F. Cestari, T. M. Carneiro, E. M. Bosqueiro, José Roberto [UNESP] |
author2_role |
author author author author author author |
dc.contributor.none.fl_str_mv |
Universidade Estadual Paulista (Unesp) Universidade Estadual de Campinas (UNICAMP) Universidade de São Paulo (USP) |
dc.contributor.author.fl_str_mv |
Rafacho, A. [UNESP] Giozzet, V. A. G. Boschero, A. C. Abrantes, J. L. F. Cestari, T. M. Carneiro, E. M. Bosqueiro, José Roberto [UNESP] |
dc.subject.por.fl_str_mv |
β-cell mass Insulin signaling Low-protein diet Pancreatic islets Protein phosphorylation |
topic |
β-cell mass Insulin signaling Low-protein diet Pancreatic islets Protein phosphorylation |
description |
A low-protein diet leads to functional and structural pancreatic islet alterations, including islet hypotrophy. Insulin-signaling pathways are involved in several adaptive responses by pancreatic islets. We determined the levels of some insulin-signaling proteins related to pancreatic islet function and growth in malnourished rats. Adult male Wistar rats (N = 20 per group) were fed a 17% protein (normal-protein diet; NP) or 6% protein (low-protein diet; LP), for 8 weeks. At the end of this period, blood glucose and serum insulin and albumin levels were measured. The morphometric parameters of the endocrine pancreas and the content of some proteins in islet lysates were determined. The β-cell mass was significantly reduced (≅65%) in normoglycemic but hypoinsulinemic LP rats compared to NP rats. Associated with these alterations, a significant 30% reduction in insulin receptor substrate-1 and a 70% increase in insulin receptor substrate-2 protein content were observed in LP islets compared to NP islets. The phosphorylated serine-threonine protein kinase (pAkt)/Akt protein ratio was similar in LP and NP islets. The phosphorylated forkhead-O1 (pFoxO1)/FoxO1 protein ratio was decreased by 43% in LP islets compared to NP islets (P < 0.05). Finally, the ratio of phosphorylated-extracellular signal-related kinase 1/2 (pErk1/2) to total Erk1/2 protein levels was decreased by 71% in LP islets compared to NP islets (P < 0.05). Therefore, the reduced β-cell mass observed in LP rats is associated with the reduction of phosphorylation in mitogenic-related signals, FoxO1 and Erk proteins. The cause/effect basis of this association remains to be determined. |
publishDate |
2009 |
dc.date.none.fl_str_mv |
2009-10-01 2014-05-20T13:26:04Z 2014-05-20T13:26:04Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://dx.doi.org/10.1590/S0100-879X2009001000010 Brazilian Journal of Medical and Biological Research. Associação Brasileira de Divulgação Científica, v. 42, n. 10, p. 935-941, 2009. 0100-879X http://hdl.handle.net/11449/8343 10.1590/S0100-879X2009001000010 S0100-879X2009001000010 WOS:000270233400010 S0100-879X2009001000010.pdf 2423477869556138 |
url |
http://dx.doi.org/10.1590/S0100-879X2009001000010 http://hdl.handle.net/11449/8343 |
identifier_str_mv |
Brazilian Journal of Medical and Biological Research. Associação Brasileira de Divulgação Científica, v. 42, n. 10, p. 935-941, 2009. 0100-879X 10.1590/S0100-879X2009001000010 S0100-879X2009001000010 WOS:000270233400010 S0100-879X2009001000010.pdf 2423477869556138 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Brazilian Journal of Medical and Biological Research 1.492 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
935-941 application/pdf |
dc.publisher.none.fl_str_mv |
Associação Brasileira de Divulgação Científica (ABRADIC) |
publisher.none.fl_str_mv |
Associação Brasileira de Divulgação Científica (ABRADIC) |
dc.source.none.fl_str_mv |
SciELO reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
_version_ |
1799965379946086400 |