Free fatty acid receptor 2 (FFAR2) and Free fatty acid receptor 3 (FFAR3) (FFAR2, FFAR3)

The term "Propionate receptor" most commonly refers to two closely related human G protein-coupled receptors—Free fatty acid receptor 2 (FFAR2/GPR43) and Free fatty acid receptor 3 (FFAR3/GPR41)—that are activated by short-chain fatty acids such as propionate. These receptors play key roles in mediating the physiological effects of dietary fiber fermentation products on host metabolism, inflammation control, cardiovascular function, and immune responses. Both FFAR2 and FFAR3 are expressed in a variety of tissues including the gut epithelium and immune cells. They transduce extracellular signals from microbial metabolites into cellular responses through classic GPCR signaling pathways involving different types of G proteins. While they represent promising therapeutic targets for metabolic diseases and inflammatory conditions due to their central role in host-microbe interactions,[5][7][8] there is ongoing research into selective modulators for clinical use. Note: The phrase "propionate receptor" is not a canonical name; it should be mapped specifically to "Free fatty acid receptor 2" (FFAR2/GPR43) or "Free fatty acid receptor 3" (FFAR3/GPR41), both recognized as primary molecular sensors for propionate among other short-chain fatty acids.[5][7]

Other names

G protein-coupled receptor 43 (GPR43) [for FFAR2]G protein-coupled receptor 41 (GPR41) [for FFAR3]Short-chain fatty acid receptor

Drugs or endogenous ligands activate or inhibit the receptors by binding to their orthosteric sites, leading to downstream signaling via G proteins that modulate immune responses, metabolic pathways, and hormone secretion[5][7][8].