NE 52-QQ57 is a selective, and orally available antagonist of G-protein coupled receptor 4 (GPR4) with IC50 of 0.07 μM. NE 52-QQ57 effectively blocks GPR4-mediated cAMP accumulation with IC50 of 26.8 nM in HEK293 cells. The antagonism of GPR4 with NE 52-QQ57 significantly inhibits the AGE-induced increased expression of several key inflammatory cytokines and signaling molecules, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, inducible nitric oxide synthase (iNOS), nitric oxide (NO), cyclooxygenase 2 (COX2), and prostaglandin E2 (PGE2).