Pancreas-specific Sirt1-deficiency in mice compromises beta-cell function without development of hyperglycemia

Andreia V. Pinho, Mohammed Bensellam, Elke Wauters, Maxine Rees, Marc Giry-Laterriere, Amanda Mawson, Le Quan Ly, Andrew V. Biankin, Jianmin Wu, D. Ross Laybutt, Ilse Rooman

Research output: Contribution to journalArticlepeer-review

29 Citations (Scopus)
65 Downloads (Pure)

Abstract

Aims/Hypothesis: Sirtuin 1 (Sirt1) has been reported to be a critical positive regulator of glucose-stimulated insulin secretion in pancreatic beta-cells. The effects on islet cells and blood glucose levels when Sirt1 is deleted specifically in the pancreas are still unclear. Methods: This study examined islet glucose responsiveness, blood glucose levels, pancreatic islet histology and gene expression in Pdx1Cre; Sirt1ex4F/F mice that have loss of function and loss of expression of Sirt1 specifically in the pancreas. Results: We found that in the Pdx1Cre; Sirt1ex4F/F mice, the relative insulin positive area and the islet size distribution were unchanged. However, beta-cells were functionally impaired, presenting with lower glucose-stimulated insulin secretion. This defect was not due to a reduced expression of insulin but was associated with a decreased expression of the glucose transporter Slc2a2/Glut2 and of the Glucagon like peptide-1 receptor (Glp1r) as well as a marked down regulation of endoplasmic reticulum (ER) chaperones that participate in the Unfolded Protein Response (UPR) pathway. Counter intuitively, the Sirt1-deficient mice did not develop hyperglycemia. Pancreatic polypeptide (PP) cells were the only other islet cells affected, with reduced numbers in the Sirt1-deficient pancreas. Conclusions/Interpretation: This study provides new mechanistic insights showing that beta-cell function in Sirt1-deficient pancreas is affected due to altered glucose sensing and deregulation of the UPR pathway. Interestingly, we uncovered a context in which impaired beta-cell function is not accompanied by increased glycemia. This points to a unique compensatory mechanism. Given the reduction in PP, investigation of its role in the control of blood glucose is warranted.

Original languageEnglish
Article numbere0128012
Pages (from-to)1-13
Number of pages13
JournalPLoS ONE
Volume10
Issue number6
DOIs
Publication statusPublished - 5 Jun 2015
Externally publishedYes

Bibliographical note

Copyright the Author(s) 2015. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.

Fingerprint

Dive into the research topics of 'Pancreas-specific Sirt1-deficiency in mice compromises beta-cell function without development of hyperglycemia'. Together they form a unique fingerprint.

Cite this