FFAR2

FFAR2 (free fatty acid receptor 2, also known as GPR43) is a short-chain fatty acid (SCFA)-sensing G protein-coupled receptor that links microbiota-derived metabolites to host immune and metabolic responses^[1][2]. Mechanistically, FFAR2 is activated by acetate, propionate, and butyrate and regulates intracellular signaling pathways involved in leukocyte activation, chemotaxis, cytokine production, and epithelial barrier function^[1][3]. Through these processes, FFAR2 contributes to the coordination of innate immune responses and maintenance of intestinal homeostasis, establishing a functional connection between dietary fiber fermentation and host physiology^[2][3]. In disease-relevant settings, FFAR2 has been extensively studied in inflammatory bowel disease, metabolic disorders, infection models, and other conditions characterized by dysregulated immune responses, where modulation of SCFA-FFAR2 signaling influences inflammatory outcomes and tissue protection^[2][3][4]. Compared with the closely related receptor FFAR3 (GPR41), which also recognizes SCFAs, FFAR2 displays distinct ligand preferences, signaling properties, and immune-cell expression patterns, particularly its prominent expression in neutrophils and other leukocyte populations^[1][4]. This distinction has made FFAR2 a key target for dissecting receptor-specific effects of microbial metabolites in experimental systems^[4]. For research applications, multiple synthetic agonists and antagonists have been developed to investigate FFAR2 biology, including selective pharmacological probes and the clinical-stage antagonist GLPG0974, enabling mechanistic studies of receptor signaling and therapeutic target validation^[5].