Publication details
Role of CD36 and GPR120 in fatty acid-mediated Ca2+Signaling in human and mouse taste bud cells
| Authors | |
|---|---|
| Year of publication | 2014 |
| Type | Article in Proceedings |
| Conference | Chemical Senses |
| MU Faculty or unit | |
| Citation | |
| Doi | http://dx.doi.org/10.1093/chemse/bju073 |
| Field | Physiology |
| Keywords | lipids; oral; sense |
| Description | Oral perception of dietary fat was until recently thought to involve mainly texture and olfactory cues; however, accumulating evidence strongly suggests existence of a taste modality, devoted to the detection of long-chain fatty acids (LCFA). Mice can recognize dietary fat and FA solutions in the oral cavity in the absence of olfactory or textural cues. Hence, it is important to increase our understanding of gustatory detection of dietary fat and its contribution to fat preference. We studied the roles of the fat taste receptors CD36 and GPR120 and their interactions via Ca2+ signaling in fungiform taste bud cells (TBC). We measured Ca2+ signaling in human TBC, transfected with small interfering RNAs (siRNAs) against mRNAs encoding CD36 and GPR120 (or control siRNAs). We also studied Ca2+signaling in TBC from CD36–/– mice and from wild-type lean and obese mice. Additional studies were conducted with mouse enteroendocrine cell line STC-1 that express GPR120 and stably transfected with human CD36. We measured release of serotonin and GLP-1 from human and mice TBC in response to CD36 and GPR120 activation. High concentrations of linoleic acid induced Ca2+ signaling via CD36 and GPR120 in human and mice TBC as well as in STC-1 cells, whereas low concentrations induced Ca2+ signaling via only CD36. Incubation of human and mice fungiform TBC with lineoleic acid downregulated CD36 and upregulated GPR120 in membrane lipid rafts. Obese mice had decreased spontaneous preference for fat. Fungiform TBC from obese mice had reduced Ca2+ and serotonin responses but increased release of Glp1, along with reduced levels of Cd36 and increased levels of Gpr120 in lipid rafts. CD36 and GPR120 have non-overlapping roles in TBC signaling during oro-gustatory perception of dietary lipids; these are differentially regulated by obesity |