Reduced pancreatic β-cell mass is associated with decreased FoxO1 and Erk1/2 protein phosphorylation in low-protein malnourished rats

Detalhes bibliográficos
Autor(a) principal: Rafacho, A. [UNESP]
Data de Publicação: 2009
Outros Autores: Giozzet, V. A. G., Boschero, A. C., Abrantes, J. L. F., Cestari, T. M., Carneiro, E. M., Bosqueiro, José Roberto [UNESP]
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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spelling 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
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