Discovery of Selective P2Y₆R Antagonists with High Affinity and <i>In Vivo</i> Efficacy for Inflammatory Disease Therapy

As a member of purinoceptors, the P2Y6 receptor (P2Y6R) plays a crucial role in modulating immune signals and has been considered as a potential therapeutic target for inflammatory diseases. On the basis of the speculated probable conformation and binding determinants of P2Y6R, a hierarchical strategy that combines virtual screening, bioassays, and chemical optimization was presented. A potent P2Y6R antagonist (compound 50) was identified to possess excellent antagonistic activity (IC50 = 5.914 nM) and high selectivity. In addition, binding assays and chemical pull-down experiments confirmed that compound 50 was nicely bound to P2Y6R. Notably, compound 50 could effectively ameliorate DSS-induced ulcerative colitis in mice through inhibiting the activation of NLRP3 inflammasome in colon tissues. Moreover, treatment with compound 50 reduced LPS-induced pulmonary edema and infiltration of inflammatory cells in mice. These findings suggest that compound 50 could serve as a specific P2Y6R antagonist for treating inflammatory diseases and deserve further optimization studies.作为嘌呤能受体（purinoceptors）家族成员，P2Y6受体（P2Y6 receptor, P2Y6R）在调控免疫信号通路中发挥关键作用，被视为炎症性疾病的潜在治疗靶点。基于P2Y6R的推测合理构象与结合决定簇，本研究提出了一种整合虚拟筛选、生物测定与化学优化的分层研究策略。研究成功鉴定出一种强效P2Y6R拮抗剂（化合物50），其具备优异的拮抗活性（IC50 = 5.914 nM）与极高的选择性。此外，结合实验与化学下拉实验证实，化合物50可与P2Y6R特异性结合。值得注意的是，化合物50可通过抑制结肠组织中NLRP3炎症小体（NLRP3 inflammasome）的活化，有效改善葡聚糖硫酸钠（DSS）诱导的小鼠溃疡性结肠炎。进一步研究显示，化合物50处理可减轻脂多糖（LPS）诱导的小鼠肺水肿与炎症细胞浸润。上述研究结果表明，化合物50可作为特异性P2Y6R拮抗剂用于炎症性疾病的治疗，具备进一步优化的研究价值。