Research Center for Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, China; Shenzhen Pingle Orthopaedic Hospital (Shenzhen Pingshan Traditional Chinese Medicine Hospital), Shenzhen, 518118, China.
Research Center for Drug Discovery, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, China.
Eur J Med Chem. 2020 Nov 15;206:112793. doi: 10.1016/j.ejmech.2020.112793. Epub 2020 Sep 6.
Based on the co-crystal structures of LXRβ and its agonists (spiro [pyrrolidine-3,3'-oxindole] derivatives) discovered by us previously, we designed and synthesized a compound library to explore the agonistic activities. The library was screened with luciferase reporter assays, interestingly, it resulted in the discovery of 10 LXR inverse agonists besides 5 LXR agonists. To clarify the mechanism of the actions, we conducted molecular dynamics (MD) simulations on the LXR and inverse agonists complexes, and revealed that H3, H11 and H12 configurations are the key to turn on agonism or inverse agonism status for LXR. Binding tightly with H3, pushing H11 out and destabilizing H12 could form a bigger hydrophobic groove to accommodate NCOR1 to turn on LXR inverse agonism. The inverse agonist 10rr was further studied, and found as a lipogenesis inhibitor through down-regulating LXR target genes SREBP-1c, ACC, FAS and SCD-1, and demonstrated lipid-lowering effects in 3T3-L1 cells, HepG2 cells and mice with Triton WR-1339-induced hyperlipidemia. Therefore, we have proved that LXR inverse agonists can be promising agents for hyperlipidemia treatment.
基于我们之前发现的 LXRβ 及其激动剂（螺吡咯[吡咯烷-3,3'-吲哚]衍生物）的共晶结构，我们设计并合成了一个化合物文库，以探索激动剂的活性。该文库通过荧光素酶报告基因检测进行筛选，有趣的是，除了 5 种 LXR 激动剂外，还发现了 10 种 LXR 反向激动剂。为了阐明作用机制，我们对 LXR 和反向激动剂复合物进行了分子动力学（MD）模拟，结果表明 H3、H11 和 H12 的构象是决定 LXR 激动或反向激动状态的关键。与 H3 紧密结合，将 H11 推出并破坏 H12 的稳定性，可以形成一个更大的疏水性凹槽，容纳 NCOR1 以开启 LXR 反向激动作用。进一步研究了反向激动剂 10rr，发现它可以通过下调 LXR 靶基因 SREBP-1c、ACC、FAS 和 SCD-1 来抑制脂肪生成，并在 3T3-L1 细胞、HepG2 细胞和 Triton WR-1339 诱导的高脂血症小鼠中显示出降脂作用。因此，我们已经证明 LXR 反向激动剂可能是治疗高血脂症的有前途的药物。
