PUBLICATION

Evaluation of the insulinotropic and glucose-lowering actions of zebrafish GIP in mammalian systems: evidence for involvement of the GLP-1 receptor

Authors
Graham, G.V., Conlon, J.M., Abdel-Wahab, Y.H., Gault, V.A., Flatt, P.R.
ID
ZDB-PUB-171122-4
Date
2017
Source
Peptides   100: 182-189 (Journal)
Registered Authors
Keywords
GIP, GLP-1, Type 2 diabetes, evolution, glucagon, zebrafish
MeSH Terms
  • Animals
  • Blood Glucose/drug effects
  • Disease Models, Animal
  • Gastric Inhibitory Polypeptide/administration & dosage*
  • Gastric Inhibitory Polypeptide/genetics
  • Glucagon/metabolism
  • Glucagon-Like Peptide-1 Receptor/metabolism*
  • Glucose/metabolism
  • Glucose Tolerance Test
  • HEK293 Cells
  • Humans
  • Insulin/metabolism*
  • Insulin-Secreting Cells/drug effects
  • Insulin-Secreting Cells/metabolism
  • Mice
  • Rats
  • Receptors, Gastrointestinal Hormone/genetics*
  • Receptors, Glucagon/genetics
  • Zebrafish/metabolism
PubMed
29157578 Full text @ Peptides
Abstract
The insulinotropic properties of zebrafish GIP (zfGIP) were assessed in vitro using clonal pancreatic β-cell lines and isolated mouse islets and acute effects on glucose tolerance and insulin release in vivo were evaluated in mice. The peptide produced a dose-dependent increase in the rate of insulin release from BRIN-BD11 rat clonal β-cells at concentrations ≥30nM. Insulin release from 1.1 B4 human clonal β-cells and mouse islets was significantly increased by zfGIP (10nM and 1μM). The in vitro insulinotropic activity of zfGIP was decreased after incubating BRIN-BD11 cells with the GLP-1 receptor antagonist, exendin-4(9-39) (p<0.001) and the GIP receptor antagonist, GIP (6-30) Cex-K40[Pal] (p<0.05) but the glucagon receptor antagonist [des-His1,Pro4,Glu9]glucagon amide was without effect. zfGIP (10nM and 1μM) produced significant increases in cAMP concentration in CHL cells transfected with the human GLP-1 receptor but was without effect on HEK293 cells transfected with the human glucagon receptor. Conversely, zfGIP, but not human GIP, significantly stimulated insulin release from CRISPR/Cas9-engineered INS-1 clonal β-cells from which the GIP receptor had been deleted. Intraperitoneal administration of zfGIP (25 and 75nmol/kg body weight) to mice together with an intraperitoneal glucose load (18mmol/kg body weight) produced a significant decrease in plasma glucose concentrations concomitant with an increase in insulin concentrations. The study provides evidence that the insulinotropic action of zfGIP in mammalian systems involves activation of both the GLP-1 and the GIP receptors but not the glucagon receptor.
Genes / Markers
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Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
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Orthology
Engineered Foreign Genes
Mapping