The Lipid-Sensor Candidates CD36 and GPR120 Are Differentially Regulated by Dietary Lipids in Mouse Taste Buds: Impact on Spontaneous Fat Preference

• Published in: PloS one Vol. 6; no. 8; p. e24014
• Main Authors: Martin, Céline, Passilly-Degrace, Patricia, Gaillard, Dany, Merlin, Jean-François, Chevrot, Michaël, Besnard, Philippe
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 25.08.2011; Public Library of Science (PLoS)
• Subjects: Animals; Biology; Blotting, Western; CD36 antigen; CD36 Antigens - genetics; CD36 Antigens - metabolism; Chemoreception; Circadian Rhythm; Deactivation; Diet; Dietary Fats - pharmacology; Diurnal; Down-regulation; Experiments; Fatty acids; Food; Food intake; Food preferences; Food Preferences - drug effects; Food Preferences - physiology; Gene expression; Gene Expression - drug effects; Genes; Glycoproteins; Human subjects; Immunohistochemistry; Inactivation; Kinases; Laboratory animals; Lipids; Male; Medicine; Messenger RNA; Mice; Mice, Knockout; Motivation; Mutation; Nutrition; Obesity; Oral cavity; Papillae; Peptides; Pharmacology; Physiology; Post-transcription; Preferences; Protein folding; Proteins; Real-Time Polymerase Chain Reaction; Receptors; Receptors, G-Protein-Coupled - genetics; Receptors, G-Protein-Coupled - metabolism; Rodents; Satiety; Sensors; Sensory perception; Soybeans; Taste; Taste buds; Taste Buds - drug effects; Taste Buds - metabolism; Vegetable oils; France
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0024014

Recent studies in rodents and humans suggest that the chemoreception of long-chain fatty acids (LCFA) in oral cavity is involved in the spontaneous preference for fatty foods and might contribute to the obesity risk. CD36 and GPR120 are LCFA receptors identified in rodent taste bud cells. The fact that CD36 or GPR120 gene inactivation leads to a decrease in the preference for lipids raises the question of the respective role(s) played by these gustatory lipid-sensor candidates. Using a combination of biochemical, nutritional and behavioural studies in wild-type, CD36(+/-)and CD36(-/-) mice, it was found that: 1°) CD36 and GPR120 display different diurnal rhythms in the gustatory circumvallate papillae, CD36 mRNA levels being down-regulated during the dark period in contrast to GPR120, 2°) this change is due to food intake and strictly dependent of the presence of lipids in the diet, 3°) CD36 protein levels are also rapidly but transiently decreased by the food intake, a two-fold drop in CD36 protein levels being found 1 h after refeeding, followed by a progressive return to the pre-prandial values, 4°) this down-regulation, which has a post-transcriptional origin, seems sufficient to alter the spontaneous fat preference, independently to change in the GPR120 gene expression. In contrast to GPR120, CD36 appears to be a food-sensitive lipid sensor in the gustatory circumvallate papillae. Lipid-mediated change in lingual CD36 expression might modulate the motivation for fat during a meal, initially high and then gradually decreasing secondary to the food intake. This short-term lipid-mediated effect is reminiscent of sensory-specific satiety. These findings, which highlight the role played by CD36 in the oro-sensory perception of dietary lipids, raise the possibility of novel pharmacological strategies to modify attraction for fatty foods and decrease obesity risks.