Meeting Abstract

P1.106  Sunday, Jan. 4  Fatty acid taste receptor expression during cold-induced changes in dietary lipid preference in Mus musculus HUNTER-SMITH, Sarah; HUANG, Liquan; HIEBERT, Sara M*; Monell Chemical Senses Center; Monell Chemical Senses Center; Swarthmore College shieber1@swarthmore.edu

Previous studies have shown that heterotherms such as the Siberian hamster Phodopus sungorus as well as an obligate homeotherm, the outbred ICR (CD-1) mouse Mus musculus, increase their preference for a diet rich in polyunsaturated fatty acids (PUFAs) when they are exposed to a cold environment. However, the proximate mechanism by which this change in preference is brought about, and specifically the role of taste receptors in this process, have not previously been investigated. After two weeks at 22 C, during which each mouse established its baseline preference for a PUFA-rich diet relative to a simultaneously offered SFA (saturated fatty acid)-rich diet, one treatment group was moved to 5 C while the control group remained at 22 C. Over the following three weeks, the cold treatment group developed a significantly higher preference for the PUFA-rich diet than 22 C controls. We used quantitative real-time PCR analysis of tongue tissues obtained after three weeks of cold exposure to examine the expression of several genes reportedly involved in fat taste (CD36, GPR120, and several delayed rectifying potassium channels) as well as three genes involved in sweet, bitter, and umami taste (TrpM5, gustducin, and T1R3) for comparison. Expression of the putative long-chain unsaturated fatty acid taste receptor GPR120 was significantly higher in the cold-treatment group, in circumvallate and foliate papillae as well as in non-taste epithelium. In addition, GPR120 expression was significantly correlated with PUFA-rich diet preference. These data suggest that GPR120 contributes to the observed cold-induced changes in lipid preference by increasing PUFA sensitivity through both taste and trigeminal pathways.