Glucagon-like peptide 1 potentiates glucotoxicity-diminished insulin secretion via stimulation of cAMP-PKA signaling in INS-1E cells and mouse islets

2013 ◽  
Vol 45 (2) ◽  
pp. 483-490 ◽  
Author(s):  
Guochun Luo ◽  
Xiangchen Kong ◽  
Lina Lu ◽  
Xiaohui Xu ◽  
Hui Wang ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Mouse Islets ◽  
Glucagon Like Peptide ◽  
Glucagon Like Peptide 1 ◽  
Stimulation Of

scholarly journals cAMP-Mediated and Metabolic Amplification of Insulin Secretion Are Distinct Pathways Sharing Independence of β-Cell Microfilaments

Endocrinology ◽  
2012 ◽  
Vol 153 (10) ◽  
pp. 4644-4654 ◽  
Author(s):  
Nizar I. Mourad ◽  
Myriam Nenquin ◽  
Jean-Claude Henquin
Keyword(s):  
Insulin Secretion ◽  
Actin Polymerization ◽  
Cytosolic Calcium ◽  
Actin Microfilaments ◽  
Insulin Granules ◽  
Adenylate Cyclase Stimulation ◽  
Mouse Islets ◽  
Glucagon Like Peptide ◽  
Glucagon Like Peptide 1 ◽  
Camp Levels

Abstract Insulin secretion is triggered by an increase in the cytosolic calcium concentration ([Ca2+]c) in β-cells. Ca2+-induced exocytosis of insulin granules can be augmented by metabolic amplification (unknown signals generated through glucose metabolism) or neurohormonal amplification (in particular cAMP mediated). Functional actin microfilaments are not required for metabolic amplification, but their possible role in cAMP-mediated amplification is unknown. It is also uncertain whether cAMP (generated in response to glucose) is implicated in metabolic amplification. These questions were addressed using isolated mouse islets. cAMP levels were increased by phosphodiesterase inhibition (with isobutylmethylxanthine) and adenylate-cyclase stimulation (with forskolin or glucagon-like peptide-1, 7-36 amide). Raising cAMP levels had no steady-state impact on actin polymerization in control islets. Neither disruption (depolymerization by latrunculin) nor stabilization (polymerization by jasplakinolide) of actin microfilaments was counteracted by cAMP. Both changes increased both phases of glucose- or tolbutamide-induced insulin secretion but did not prevent further amplification by cAMP. These large changes in secretion were not caused by changes in [Ca2+]c, which was only slightly increased by cAMP. Both phases of insulin secretion were larger in response to glucose than tolbutamide, although [Ca2+]c was lower. This difference in secretion, which reflects metabolic amplification, was independent of microfilaments, was not attributable to differences in cAMP, and persisted in presence of dibutyryl-cAMP or when cAMP levels were variably raised by isobutylmethylxanthine + forskolin or glucagon-like peptide-1, 7-36 amide. We conclude that metabolic and cAMP-mediated amplification of insulin secretion are distinct pathways that accelerate acquisition of release competence by insulin granules that can access exocytotic sites without intervention of microfilaments.

Stimulation of glucagon-like peptide-1 secretion by water loading in human

2014 ◽  
Vol 459 (1) ◽  
pp. 323-325 ◽  
Author(s):  
A. S. Marina ◽  
A. V. Kutina ◽  
E. I. Shakhmatova ◽  
E. V. Balbotkina ◽  
Yu. V. Natochin
Keyword(s):  
Water Loading ◽  
Glucagon Like Peptide ◽  
Glucagon Like Peptide 1 ◽  
Stimulation Of

The Effect of Zinc-Crystallized Glucagon-Like Peptide-1 on Insulin Secretion of Macroencapsulated Pancreatic Islets

2001 ◽  
Vol 7 (1) ◽  
pp. 35-44 ◽  
Author(s):  
Heather Gappa ◽  
Miroslav Baudyš ◽  
Jae Joon Koh ◽  
Sung Wan Kim ◽  
You Han Bae
Keyword(s):  
Insulin Secretion ◽  
Pancreatic Islets ◽  
Glucagon Like Peptide ◽  
Glucagon Like Peptide 1

scholarly journals Subthreshold α2-Adrenergic Activation Counteracts Glucagon-Like Peptide-1 Potentiation of Glucose-Stimulated Insulin Secretion

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Minglin Pan ◽  
Guang Yang ◽  
Xiuli Cui ◽  
Shao-Nian Yang
Keyword(s):  
Insulin Secretion ◽  
Insulin Release ◽  
Adrenergic Agonist ◽  
Signaling Systems ◽  
Glucagon Like Peptide ◽  
Glucagon Like Peptide 1 ◽  
Glucose Stimulated Insulin Secretion ◽  
Insulin Secretory Response ◽  
Adrenergic Activation ◽  
Gi Proteins

The pancreatic β cell harbors α2-adrenergic and glucagon-like peptide-1 (GLP-1) receptors on its plasma membrane to sense the corresponding ligands adrenaline/noradrenaline and GLP-1 to govern glucose-stimulated insulin secretion. However, it is not known whether these two signaling systems interact to gain the adequate and timely control of insulin release in response to glucose. The present work shows that the α2-adrenergic agonist clonidine concentration-dependently depresses glucose-stimulated insulin secretion from INS-1 cells. On the contrary, GLP-1 concentration-dependently potentiates insulin secretory response to glucose. Importantly, the present work reveals that subthreshold α2-adrenergic activation with clonidine counteracts GLP-1 potentiation of glucose-induced insulin secretion. This counteractory process relies on pertussis toxin- (PTX-) sensitive Gi proteins since it no longer occurs following PTX-mediated inactivation of Gi proteins. The counteraction of GLP-1 potentiation of glucose-stimulated insulin secretion by subthreshold α2-adrenergic activation is likely to serve as a molecular mechanism for the delicate regulation of insulin release.

Self-inducible secretion of glucagon-like peptide-1 (GLP-1) that allows MIN6 cells to maintain insulin secretion and insure cell survival

2012 ◽  
Vol 349 (2) ◽  
pp. 281-288 ◽  
Author(s):  
Koji Nakashima ◽  
Masashi Shimoda ◽  
Sumiko Hamamoto ◽  
Fuminori Tatsumi ◽  
Hidenori Hirukawa ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Cell Survival ◽  
Min6 Cells ◽  
Glucagon Like Peptide ◽  
Glucagon Like Peptide 1
Sign in / Sign up

Export Citation Format

Share Document