Discovery of Novel P2Y ₁₄ R Inhibitors for Ameliorating Liver Fibrosis by Suppressing Hepatic Stellate Cell Activation

The P2Y₁₄ purinergic receptor (P2Y₁₄R) plays a crucial role in the progression of liver fibrosis, and selective inhibition of this receptor has emerged as a promising therapeutic approach. In this study, an integrative computational pipeline identified a unique and highly flexible binding pocket within P2Y₁₄R, which is divided into two quasi-symmetrical subdomains. Leveraging this structural feature, we designed and synthesized two novel families of inhibitors based on benzoxazole-urea and benzoxazole-squaramide scaffolds. The lead compound, <b>47</b> (<b>HDB-1</b>), demonstrates exceptional potency (IC₅₀ = 0.026 nM) and superior metabolic stability. HDB-1 exhibited antihepatic fibrosis activity both <i>in vivo</i> and <i>in vitro.</i> Mechanistically, <b>HDB-1</b> inhibits P2Y₁₄R-mediated signaling by suppressing the PKA/Raf1/MEK/ERK cascade, thereby preventing the activation of hepatic stellate cells-the central pathological event in fibrosis development. Taken together, <b>HDB-1</b> represents a novel and potent P2Y₁₄R inhibitor with strong potential as an available therapeutic for liver fibrosis driven by dysregulated P2Y₁₄R signaling.