LPAR5

LPAR5 (lysophosphatidic acid receptor 5) is a G protein-coupled receptor for lysophosphatidic acid (LPA) and belongs to the non-EDG family of LPA receptors, where it mediates extracellular lipid signaling through multiple G-protein pathways including G_12/13, G_q, and cAMP-associated signaling mechanisms^[1][2]. Mechanistically, LPAR5 activation regulates cytoskeletal remodeling, intracellular calcium mobilization, receptor internalization, and inflammatory signaling, thereby influencing cell migration and immune-cell responses^[2][3]. In the central nervous system, the LPA-LPAR5 axis promotes microglial activation and induces a pro-inflammatory and migratory phenotype characterized by activation of MAPK, AKT, NF-κB, STAT, and related signaling pathways^[3][4]. Disease-associated studies further demonstrate that LPAR5 contributes to neuropathic pain, neuroinflammatory processes, itch, and cancer-related phenotypes, while altered receptor activity has been linked to tumor cell proliferation, migration, invasion, and modulation of tumor immunity^[4][5]. Compared with the classical EDG-family receptors LPAR1-3, LPAR5 belongs to the structurally distinct non-EDG subgroup and exhibits unique signaling properties that include robust coupling to G_12/13 and G_q-dependent pathways as well as context-dependent regulation of immune-cell function^[1][2]. For experimental applications, selective small-molecule antagonists including AS2717638, Compound 3, and TCLPA5 have been used to suppress LPAR5-dependent inflammatory signaling and represent valuable pharmacological tools for investigating neuroinflammation, immune regulation, and LPA receptor biology^[3][4][5].