School of Pharmacy, Fudan University, No.826, Zhangheng Rd, Shanghai, 201203, China; Institute for Agro-food Standards and Testing Technology, Shanghai Academy of Agricultural Sciences, No.1000, Jinqi Rd., Shanghai, 201403, China.
School of Pharmacy, Fudan University, No.826, Zhangheng Rd, Shanghai, 201203, China; Eye Ear Nose Throat Hospital, Fudan University, No. 83, Fenyang Rd., Shanghai, 200031, China.
Eur J Med Chem. 2019 Feb 1;163:864-882. doi: 10.1016/j.ejmech.2018.12.028. Epub 2018 Dec 13.
The sphingomyelin synthase 2 (SMS2) is a potential target for pharmacological intervention in atherosclerosis. However, so far, few selective SMS2 inhibitors and their pharmacological activities were reported. In this study, a class of 2-benzyloxybenzamides were discovered as novel SMS2 inhibitors through scaffold hopping and structural optimization. Among them, Ly93 as one of the most potent inhibitors exhibited IC values of 91 nM and 133.9 μM against purified SMS2 and SMS1 respectively. The selectivity ratio of Ly93 was more than 1400-fold for purified SMS2 over SMS1. The in vitro studies indicated that Ly93 not only dose-dependently diminished apoB secretion from Huh7 cells, but also significantly reduced the SMS activity and increased cholesterol efflux from macrophages. Meanwhile, Ly93 inhibited the secretion of LPS-mediated pro-inflammatory cytokine and chemokine in macrophages. The pharmacokinetic profiles of Ly93 performed on C57BL/6J mice demonstrated that Ly93 was orally efficacious. As a potent selective SMS2 inhibitor, Ly93 significantly decreased the plasma SM levels of C57BL/6J mice. Furthermore, Ly93 was capable of dose-dependently attenuating the atherosclerotic lesions in the root and the entire aorta as well as macrophage content in lesions, in apolipoprotein E gene knockout mice treated with Ly93. In conclusion, we discovered a novel selective SMS2 inhibitor Ly93 and demonstrated its anti-atherosclerotic activities in vivo. The preliminary molecular mechanism-of-action studies revealed its function in lipid homeostasis and inflammation process, which indicated that the selective inhibition of SMS2 would be a promising treatment for atherosclerosis.
鞘氨醇磷酸合成酶 2（SMS2）是动脉粥样硬化药物干预的潜在靶点。然而，到目前为止，很少有选择性的 SMS2 抑制剂及其药理学活性被报道。在这项研究中，通过支架跃迁和结构优化，发现了一类 2-苯氧基苯甲酰胺类化合物是新型 SMS2 抑制剂。其中，Ly93 作为最有效的抑制剂之一，对纯化的 SMS2 和 SMS1 的 IC 值分别为 91 nM 和 133.9 μM。Ly93 对纯化的 SMS2 相对于 SMS1 的选择性比值大于 1400 倍。体外研究表明，Ly93 不仅能剂量依赖性地减少 Huh7 细胞中 apoB 的分泌，而且能显著降低 SMS 活性，增加巨噬细胞中的胆固醇外排。同时，Ly93 抑制巨噬细胞中 LPS 介导的促炎细胞因子和趋化因子的分泌。在 C57BL/6J 小鼠上进行的 Ly93 的药代动力学研究表明，Ly93 具有口服疗效。作为一种有效的选择性 SMS2 抑制剂，Ly93 能显著降低 C57BL/6J 小鼠的血浆 SM 水平。此外，Ly93 能剂量依赖性地减轻载脂蛋白 E 基因敲除小鼠的动脉粥样硬化病变，包括根部和整个主动脉以及病变中的巨噬细胞含量。总之，我们发现了一种新型的选择性 SMS2 抑制剂 Ly93，并在体内证明了其抗动脉粥样硬化活性。初步的分子作用机制研究表明，它在脂质平衡和炎症过程中具有功能，这表明选择性抑制 SMS2 将是治疗动脉粥样硬化的一种有前途的方法。
