AbstractInhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) plays an increasingly important role in the treatment of hyperlipidemia. In pursuit of potent small molecules that block the PCSK9/low‐density lipoprotein receptor (LDLR) protein−protein interaction (PPI), a series of 2‐phenylquinoline‐4‐carboxylic acid derivatives were designed and synthesized based on previously derived molecules. In the in vitro PPI inhibition test, compounds M1, M12, M14, M18 and M27 exhibited potent activities with IC50 values of 6.25 μM, 0.91 μM, 2.81 μM, 4.26 μM and 0.76 μM, respectively, compared with SBC‐115337 (IC50 value of 9.24 μM). Molecular docking and molecular dynamics simulations revealed the importance of hydrophobic interactions in the binding of inhibitors to the PPI interface of PCSK9. In LDLR expression and LDL uptake assays, the tested compounds M1, M12 and M14 were found to restore LDLR expression levels and to increase the extracellular LDL uptake capacity of HepG2 cells in the presence of exogenous PCSK9. Collectively, novel small‐molecule PCSK9/LDLR PPI inhibitors (especially M12) with in vitro lipid lowering ability, were discovered as lead compounds for further development of hypolipidemic drugs.
摘要在治疗高脂血症的过程中,抑制9型丙蛋白转换酶(PCSK9)发挥着越来越重要的作用。为了寻找能阻断 PCSK9/低密度脂蛋白受体(LDLR)蛋白-蛋白相互作用(PPI)的强效小分子,我们在以前衍生分子的基础上设计并合成了一系列 2-苯基喹啉-4-羧酸衍生物。在体外 PPI 抑制试验中,化合物 M1、M12、M14、M18 和 M27 与 SBC-115337(IC50 值为 9.24 μM)相比,分别具有 6.25 μM、0.91 μM、2.81 μM、4.26 μM 和 0.76 μM 的强效活性。分子对接和分子动力学模拟揭示了疏水相互作用在抑制剂与 PCSK9 的 PPI 界面结合中的重要性。在 LDLR 表达和低密度脂蛋白摄取试验中,发现受试化合物 M1、M12 和 M14 能够恢复 LDLR 表达水平,并在外源性 PCSK9 存在的情况下提高 HepG2 细胞的细胞外低密度脂蛋白摄取能力。总之,研究人员发现了具有体外降脂能力的新型小分子 PCSK9/LDLR PPI 抑制剂(尤其是 M12),可作为进一步开发降血脂药物的先导化合物。