Protection of Human Pancreatic Islets from Lipotoxicity by Modulation of the Translocon - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue PLoS ONE Année : 2016

Protection of Human Pancreatic Islets from Lipotoxicity by Modulation of the Translocon

R. Cassel
  • Fonction : Auteur
S. Ducreux
F. Dingreville
  • Fonction : Auteur
C. Berle
  • Fonction : Auteur
K. Burda-Jacob
  • Fonction : Auteur
L. Paita
  • Fonction : Auteur
R. Al-Mawla
  • Fonction : Auteur
C. Crola da Silva
F. van Coppenolle
A. M. Madec
  • Fonction : Auteur

Résumé

Type 2 diabetes is characterized by peripheral insulin resistance and pancreatic beta cell dysfunction. Elevated free fatty acids (FFAs) may impair beta cell function and mass (lipotoxicity). Altered calcium homeostasis may be involved in defective insulin release. The endoplasmic reticulum (ER) is the major intracellular calcium store. Lipotoxicity induces ER stress and in parallel an ER calcium depletion through unknown ER calcium leak channels. The main purposes of this study is first to identify one of these channels and secondly, to check the opportunity to restore beta cells function (i.e., insulin secretion) after pharmacological inhibition of ER calcium store depletion. We investigated the functionality of translocon, an ER calcium leak channel and its involvement on FFAs-induced alterations in MIN6B1 cells and in human pancreatic islets. We evidenced that translocon acts as a functional ER calcium leak channel in human beta cells using anisomycin and puromycin (antibiotics), respectively blocker and opener of this channel. Puromycin induced a significant ER calcium release, inhibited by anisomycin pretreatment. Palmitate treatment was used as FFA model to induce a mild lipotoxic effect: ER calcium content was reduced, ER stress but not apoptosis were induced and glucose induced insulin secretion was decreased in our beta cells. Interestingly, translocon inhibition by chronic anisomycin treatment prevented dysfunctions induced by palmitate, avoiding reticular calcium depletion, ER stress and restoring insulin secretion. Our results provide for the first time compelling evidence that translocon actively participates to the palmitate-induced ER calcium leak and insulin secretion decrease in beta cells. Its inhibition reduces these lipotoxic effects. Taken together, our data indicate that TLC may be a new potential target for the treatment of type 2 diabetes.
Fichier principal
Vignette du fichier
2016_Plos One_Cassel_1.PDF (1.3 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte
Loading...

Dates et versions

hal-01850368 , version 1 (27-05-2020)

Licence

Paternité

Identifiants

Citer

R. Cassel, S. Ducreux, M. R. Alam, F. Dingreville, C. Berle, et al.. Protection of Human Pancreatic Islets from Lipotoxicity by Modulation of the Translocon. PLoS ONE, 2016, 11 (2), pp.e0148686. ⟨10.1371/journal.pone.0148686⟩. ⟨hal-01850368⟩
30 Consultations
27 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More