The sense of taste informs the organism about the quality of ingested food. It comprises five sub-modalities that perceive sweet, salt, sour, bitter, and umami stimuli. The possibility for an additional taste modality directed to lipid has often been suggested because many animals exhibit a spontaneous attraction for fats, but the existence of an actual sensor remained a matter of debate.
In a paper appearing in the November 1 issue of the Journal of Clinical Investigation, Phillipe Besnard and colleagues identify the first candidate for lipid detection in the oral cavity.
The authors combine genetic, morphological, behavioral and physiological approaches to pinpoint the multifunctional glycoprotein CD36 (also termed fatty acid transporter, FAT) as the sensor for fat. They show that lingual stimulation of CD36 by fatty acids influences behavioral and digestive physiology. CD36 gene inactivation fully abolishes both the spontaneous preference for fat and the changes in gastrointenstinal secretions mediated by oral delivery of lipids. These findings unveil one potential pathway mediating fat taste.
The data suggest that an alteration in the fat perception system might increase obesity risk through feeding dysregulation.
In an accompanying commentary, Nada Abumrad writes that this report provides insight into the basis of our preference for fat and may help us devise better strategies to address the addictive potential of dietary fat.
Source : Journal of Clinical Investigation