title: Cell mechanisms of gustatory lipids perception and modulation of the dietary fat preference.
abstract: Dietary lipids are usually responsible of several metabolic disorders. Recent compelling evidences suggest that there is a sixth taste modality, destined for the detection of oro-gustatory fats. The lipid-binding glycoprotein CD36, expressed by circumvallate papillae (CVP) of the mouse tongue, has been shown to be implicated in oro-gustatory perception of dietary lipids. We demonstrate that linoleic acid (LA) by activating sPLA2, cPLA2 and iPLA2 via CD36, produced arachidonic acid (AA) and lyso-phosphatidylcholine (Lyso-PC) which triggered Ca(2+) influx in CD36-positive taste bud cells (TBC), purified from mouse CVP. LA induced the production of Ca(2+) influx factor (CIF). CIF, AA and Lyso-PC exerted different actions on the opening of store-operated Ca2+ (SOC) channels, constituted of Orai proteins and regulated by STIM1, a sensor of Ca(2+) depletion in the endoplasmic reticulum. We observed that CIF and Lyso-PC opened Orai1 channels whereas AA-opened Ca(2+) channels were composed of Orai1/Orai3. STIM1 was found to regulate LA-induced CIF production and opening of both kinds of Ca(2+) channels. Furthermore, Stim1(-/-) mice lost the spontaneous preference for fat, observed in wild-type animals. Our results suggest that fatty acid-induced Ca(2+) signaling, regulated by STIM1 via CD36, might be implicated in oro-gustatory perception of dietary lipids and the spontaneous preference for fat. Other cell types are involved in, and external factors can influence this preference.
authors.affiliation: UMR U866 Inserm, Université de Bourgogne/AgroSup Dijon, 6, boulevard Gabriel, 21000 Dijon, France; Laboratoire de Pharmacologie et Toxicologie, Institut des Sciences Biologiques Appliquées, 06PB1623 Cotonou, Benin. Electronic address: gdramane@gmail.com.
authors.forename: Gado
authors.initials: G
authors.lastname: Dramane
authors.affiliation: Laboratoire de Biochimie, Centre Hospitalier Départemental, Université de Parakou, Parakou, Benin.
authors.forename: Simon
authors.initials: S
authors.lastname: Akpona
authors.affiliation: UMR U866 Inserm, Université de Bourgogne/AgroSup Dijon, 6, boulevard Gabriel, 21000 Dijon, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Besnard
authors.affiliation: UMR U866 Inserm, Université de Bourgogne/AgroSup Dijon, 6, boulevard Gabriel, 21000 Dijon, France.
authors.forename: Naim A
authors.initials: NA
authors.lastname: Khan
mesh_terms: D000818:Animals; D018955:CD36 Antigens / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage / Q000032:analysis*; D005518:Food Preferences / Q000502:physiology*; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D008954:Models, Biological; D009363:Neoplasm Proteins / Q000378:metabolism; D000071737:Stromal Interaction Molecule 1; D013650:Taste Buds / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D055697:Taste Perception / Q000502:physiology*
chemical_list: D018955:CD36 Antigens; D004041:Dietary Fats; D008565:Membrane Proteins; D009363:Neoplasm Proteins; C103530:STIM1 protein, human; D000071737:Stromal Interaction Molecule 1; D002118:Calcium
keywords: CD36; Calcium signaling; Dietary lipids; Lipids preference