title: The oral lipid sensor GPR120 is not indispensable for the orosensory detection of dietary lipids in mice.
abstract: Implication of the long-chain fatty acid (LCFA) receptor GPR120, also termed free fatty acid receptor 4, in the taste-guided preference for lipids is a matter of debate. To further unravel the role of GPR120 in the "taste of fat", the present study was conducted on GPR120-null mice and their wild-type littermates. Using a combination of morphological [i.e., immunohistochemical staining of circumvallate papillae (CVP)], behavioral (i.e., two-bottle preference tests, licking tests and conditioned taste aversion) and functional studies [i.e., calcium imaging in freshly isolated taste bud cells (TBCs)], we show that absence of GPR120 in the oral cavity was not associated with changes in i) gross anatomy of CVP, ii) LCFA-mediated increases in intracellular calcium levels ([Ca(2+)]i), iii) preference for oily and LCFA solutions and iv) conditioned avoidance of LCFA solutions. In contrast, the rise in [Ca(2+)]i triggered by grifolic acid, a specific GPR120 agonist, was dramatically curtailed when the GPR120 gene was lacking. Taken together, these data demonstrate that activation of lingual GPR120 and preference for fat are not connected, suggesting that GPR120 expressed in TBCs is not absolutely required for oral fat detection in mice.
authors.affiliation: NUTox, UMR U866 INSERM/Université de Bourgogne/AgroSup Dijon, F21000 Dijon, France.
authors.forename: Déborah
authors.initials: D
authors.lastname: Ancel
authors.affiliation: NUTox, UMR U866 INSERM/Université de Bourgogne/AgroSup Dijon, F21000 Dijon, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Bernard
authors.affiliation: NUTox, UMR U866 INSERM/Université de Bourgogne/AgroSup Dijon, F21000 Dijon, France.
authors.forename: Selvakumar
authors.initials: S
authors.lastname: Subramaniam
authors.affiliation: Department of Pharmacogenomics, Kyoto University Graduate School of Pharmaceutical Sciences, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Hirasawa
authors.affiliation: Department of Pharmacogenomics, Kyoto University Graduate School of Pharmaceutical Sciences, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Gozoh
authors.initials: G
authors.lastname: Tsujimoto
authors.affiliation: Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Hashimoto
authors.affiliation: NUTox, UMR U866 INSERM/Université de Bourgogne/AgroSup Dijon, F21000 Dijon, France.
authors.forename: Patricia
authors.initials: P
authors.lastname: Passilly-Degrace
authors.affiliation: NUTox, UMR U866 INSERM/Université de Bourgogne/AgroSup Dijon, F21000 Dijon, France.
authors.forename: Naim-Akhtar
authors.initials: NA
authors.lastname: Khan
authors.affiliation: NUTox, UMR U866 INSERM/Université de Bourgogne/AgroSup Dijon, F21000 Dijon, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Besnard
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D004041:Dietary Fats / Q000378:metabolism*; D005518:Food Preferences / Q000187:drug effects / Q000502:physiology; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D043562:Receptors, G-Protein-Coupled / Q000819:agonists / Q000378:metabolism*; D013650:Taste Buds / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*
chemical_list: D004041:Dietary Fats; C498007:FFAR4 protein, mouse; D043562:Receptors, G-Protein-Coupled; D002118:Calcium
keywords: G-protein; diet and dietary lipids; fat taste; feeding behavior; lipids; mouse; nutrition; receptors