Abstract
Understanding the mechanisms underlying oro-gustatory detection of dietary fat is critical for the prevention and treatment of obesity. The lipid-binding glycoprotein CD36, which is expressed by circumvallate papillae (CVP) of the mouse tongue, has been implicated in oro-gustatory perception of dietary lipids. Here, we demonstrate that stromal interaction molecule 1 (STIM1), a sensor of Ca2+ depletion in the endoplasmic reticulum, mediates fatty acid–induced Ca2+ signaling in the mouse tongue and fat preference. We showed that linoleic acid (LA) induced the production of arachidonic acid (AA) and lysophosphatidylcholine (Lyso-PC) by activating multiple phospholipase A2 isoforms via CD36. This activation triggered Ca2+ influx in CD36-positive taste bud cells (TBCs) purified from mouse CVP. LA also induced the production of Ca2+ influx factor (CIF). STIM1 was found to regulate LA-induced CIF production and the opening of multiple store-operated Ca2+ (SOC) channels. Furthermore, CD36-positive TBCs from Stim1–/– mice failed to release serotonin, and Stim1–/– mice lost the spontaneous preference for fat that was observed in wild-type animals. Our results suggest that fatty acid–induced Ca2+ signaling, regulated by STIM1 via CD36, might be implicated in oro-gustatory perception of dietary lipids and the spontaneous preference for fat.
Authors
Gado Dramane, Souleymane Abdoul-Azize, Aziz Hichami, Timo Vögtle, Simon Akpona, Christophe Chouabe, Hassimi Sadou, Bernhard Nieswandt, Philippe Besnard, Naim Akhtar Khan
Sequences of the primers used to study the expression of mRNA of different genes
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)