6533b82bfe1ef96bd128d441

RESEARCH PRODUCT

Impact of obesity on the oro-sensory detection of dietary lipids in mice and humans

subject

description

Gustation is an essential parameter in the oro-sensory detection of dietary lipids. In mice and most likely in humans, the binding of long-chain fatty acids to the CD36 receptor plays a major role in this oral fat detection. Gustation is involved in the food choice (fat sensitivity) as well as in the preparation of the body to the fat inflow. This oral lipid sensing is highly regulated. As obesity seems to be responsible for an alteration of the basic tastes detection, the aim of this thesis was to investigate whether obesity can impair the oral lipid detection in both mice and humans. In humans, our data show that there is an alteration of the oral fat detection in some obese subjects who have a higher lipid consumption than the other subjects. Besides, an early secretion of plasma triglycerides induced by an oral fat stimulation was observed in lean subjects but not in obese ones. In mice, a decrease in the dietary lipids taste sensitivity was shown to be caused by obesity. This is the consequence of a deregulation of the CD36-dependent calcium signalling in taste cells. In these mice, as in humans, the oral fat stimulation leads to a temporary increase in the blood triglyceride level which might be responsible for a reduced meal size (satiety). To conclude, obesity impairs oral lipid detection in both mice and humans. An altered dietary fat detection associated with an abolition of the early secretion of plasma triglycerides in obese people might induce an impaired regulation of the food intake, leading to an overconsumption of lipid-rich foods, and so a reinforcement of obesity