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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Reduced AMPK2 protein expression restores glucose-induced insulin secretion in islets from calorie-restricted rats

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Author(s):
Amaral, Maria Esmeria C. [1] ; Ribeiro, Rosane A. [2] ; Vanzela, Emerielle C. [3] ; Barbosa-Sampaio, Helena C. [3]
Total Authors: 4
Affiliation:
[1] UNIARARAS, Ctr Univ Herminio Ometto, Programa Posgrad Ciencias Biomed, Ave Dr Maximiliano Barutto, 500 Jd Univ Araras, BR-13607339 Araras, SP - Brazil
[2] Univ Fed Rio de Janeiro, Campus UFRJ Macae, Macae, RJ - Brazil
[3] Univ Estadual Campinas, UNICAMP, Inst Biol, Dept Biol Estrutural & Func, Campinas, SP - Brazil
Total Affiliations: 3
Document type: Journal article
Source: International Journal of Experimental Pathology; v. 97, n. 1, p. 50-55, FEB 2016.
Web of Science Citations: 3
Abstract

In a state of caloric restriction (CR), improved insulin action was associated with the activation of AMP-activated kinase (AMPK). Here, we verified whether AMPK was involved in impaired -cell function in islets from rats subjected to CR for 21days. Eight-week-old male rats were distributed into a control (CTL) group that was fed an isocaloric diet adlibitum or a CR group that received 60% of the food consumed by the CTL group. From days 18-21, CTL and CR rats were treated with sense (CTLS and CRS) or antisense (CTLAS and CRAS) AMPK2 oligonucleotides. Caloric restriction was associated with decreased body weight, perigonadal fat pads and insulinaemia, while higher glucose tolerance was observed in CRS rats. Antisense treatment normalized insulinaemia and glucose tolerance in CRAS rats and increased cholesterolaemia in CRAS and CTLAS groups. These effects were associated with reduced pAMPK/AMPK protein expression in the liver of rats treated with antisense oligonucleotides. Additionally, CRS islets showed higher pAMPK/AMPK content and lower glucose-induced insulin release. As expected, antisense oligonucleotides against AMPK2 efficiently reduced pAMPK/AMPK protein in CRAS and CTLAS islets. The lower AMPK content in CRAS islets normalized the insulin secretion in islets exposed to 16.7mM glucose. In addition, CTLAS islets presented higher insulin secretion at 2.8 and 16.7mM glucose. These findings support the hypothesis that higher AMPK protein expression is involved in impaired -cell function in islets from rats subjected to CR for 21days. (AU)

FAPESP's process: 07/08405-9 - Effect of caloric restriction in the regulation Sirt 1, Sirt 4 and AMPK on the secretory function of beta pancreatic cells in vivo and in vitro
Grantee:Maria Esméria Corezola do Amaral
Support Opportunities: Regular Research Grants