Accéder directement au contenu Accéder directement à la navigation
Article dans une revue

β-Arrestin2 plays a key role in the modulation of the pancreatic beta cell mass in mice

Abstract : AIMS/HYPOTHESIS: Beta cell failure due to progressive secretory dysfunction and limited expansion of beta cell mass is a key feature of type 2 diabetes. Beta cell function and mass are controlled by glucose and hormones/neurotransmitters that activate G protein-coupled receptors or receptor tyrosine kinases. We have investigated the role of β-arrestin (ARRB)2, a scaffold protein known to modulate such receptor signalling, in the modulation of beta cell function and mass, with a specific interest in glucagon-like peptide-1 (GLP-1), muscarinic and insulin receptors. METHODS: β-arrestin2-knockout mice and their wild-type littermates were fed a normal or a high-fat diet (HFD). Glucose tolerance, insulin sensitivity and insulin secretion were assessed in vivo. Beta cell mass was evaluated in pancreatic sections. Free cytosolic [Ca(2+)] and insulin secretion were determined using perifused islets. The insulin signalling pathway was evaluated by western blotting. RESULTS: Arrb2-knockout mice exhibited impaired glucose tolerance and insulin secretion in vivo, but normal insulin sensitivity compared with wild type. Surprisingly, the absence of ARRB2 did not affect glucose-stimulated insulin secretion or GLP-1- and acetylcholine-mediated amplifications from perifused islets, but it decreased the islet insulin content and beta cell mass. Additionally, there was no compensatory beta cell mass expansion through proliferation in response to the HFD. Furthermore, Arrb2 deletion altered the islet insulin signalling pathway. CONCLUSIONS/INTERPRETATION: ARRB2 is unlikely to be involved in the regulation of insulin secretion, but it is required for beta cell mass plasticity. Additionally, we provide new insights into the mechanisms involved in insulin signalling in beta cells.
Type de document :
Article dans une revue
Liste complète des métadonnées

Littérature citée [45 références]  Voir  Masquer  Télécharger
Contributeur : Magalie Ravier <>
Soumis le : lundi 23 mars 2020 - 17:41:32
Dernière modification le : mercredi 14 octobre 2020 - 04:04:51


Fichiers produits par l'(les) auteur(s)




Magalie Ravier, Michèle Leduc, Joy Richard, Nathalie Linck, Annie Varrault, et al.. β-Arrestin2 plays a key role in the modulation of the pancreatic beta cell mass in mice. Diabetologia, Springer Verlag, 2014, 57 (3), pp.532-541. ⟨10.1007/s00125-013-3130-7⟩. ⟨hal-02506326⟩



Consultations de la notice


Téléchargements de fichiers