title: Expression of the fatty acid receptor GPR120 in the gut of diet-induced-obese rats and its role in GLP-1 secretion.
abstract: Stimulation of the G protein coupled receptor GPR120 has been shown to have anti-inflammatory and insulin-sensitizing effects, to promote glucagon like peptide-1 (GLP-1) secretion, and to play a key role in sensing dietary fat and control energy balance. In a search for differentially expressed genes potentially involved in food intake and body-weight regulation we identified GPR120 to be differentially regulated in the intestine of selectively bred diet induced obese (DIO) and diet resistant (DR) rats. Subsequently we investigated the effect of GPR120 receptor stimulation with the long chain fatty acid alpha linolenic acid (ALA) on GLP-1 secretion in rats. Independent of diet (high or low fat), GPR120 expression showed a two-fold increase in the intestine of DIO compared to DR rats. In situ hybridization revealed a broad expression of GPR120 in the gut mucosa in both intestinal epithelial and endocrine cells. Using double in situ hybridization GPR120 mRNA did not appear to be enriched in preproglucagon expressing L-cells. In line with the anatomical data, ALA administration did not increase circulating GLP-1 levels. Our data shows a widespread expression of GPR120 in the gut epithelium and can not confirm a major role for GPR120 in the regulation of GLP-1 secretion. The broad expression of GPR120 in the gut epithelium supports reports indicating a putative role of GPR120 as a sensor of dietary fat.
authors: Department of Histology, Gubra, Hørsholm, Denmark.
authors: Sarah Juel
authors: SJ
authors: Paulsen
authors: Department of Molecular Biology, Vipergen Aps, Copenhagen, Denmark.
authors: Leif Kongskov
authors: LK
authors: Larsen
authors: Department of Histology, Gubra, Hørsholm, Denmark.
authors: Gitte
authors: G
authors: Hansen
authors: Department of Preclinical Biology, Aurigene Discovery Technologies Ltd, Bengaluru, India.
authors: Shekar
authors: S
authors: Chelur
authors: Department of Diabetes Research and Translational Science, Sanofi-Aventis, Frankfurt Am Main, Germany.
authors: Philip Just
authors: PJ
authors: Larsen
authors: Department of Histology, Gubra, Hørsholm, Denmark.
authors: Niels
authors: N
authors: Vrang
mesh_terms: D000284:Administration, Oral; D000818:Animals; D002210:Caprylates / Q000008:administration & dosage / Q000494:pharmacology; D004032:Diet; D041981:Gastrointestinal Tract / Q000187:drug effects / Q000378:metabolism*; D052216:Glucagon-Like Peptide 1 / Q000097:blood / Q000378:metabolism*; D005947:Glucose / Q000008:administration & dosage / Q000494:pharmacology; D007328:Insulin / Q000097:blood; D019787:Linoleic Acid / Q000008:administration & dosage / Q000494:pharmacology; D008297:Male; D060885:Multiplex Polymerase Chain Reaction; D009765:Obesity / Q000097:blood / Q000378:metabolism*; D052336:Proglucagon / Q000378:metabolism; D021381:Protein Transport / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*
chemical_list: D002210:Caprylates; C533284:Ffar4 protein, rat; D007328:Insulin; D043562:Receptors, G-Protein-Coupled; D052336:Proglucagon; D052216:Glucagon-Like Peptide 1; D019787:Linoleic Acid; D005947:Glucose; C031492:octanoic acid