Schwarz Patrik F, Perhal Alexander F, Guder Famke, Hernández González Jorge Enrique, Janssen Kerrin, Sağıroğlu Ece, Tahir Ammar, Kirchmair Johannes, Rochel Natacha, Dirsch Verena M, Chen Ya
Department of Pharmaceutical Sciences, Division of Pharmacognosy, Faculty of Life Sciences, University of Vienna, Josef-Holaubek-Platz 2, 1090 Vienna, Austria.
Vienna Doctoral School of Pharmaceutical, Nutritional and Sport Sciences (PhaNuSpo), University of Vienna, 1090 Vienna, Austria.
J Nat Prod. 2025 Aug 22;88(8):1887-1900. doi: 10.1021/acs.jnatprod.5c00416. Epub 2025 Jul 28.
Targeting retinoic acid-related orphan receptor γ (RORγ) with inverse agonists presents a promising therapeutic strategy for treating autoimmune diseases, including psoriasis, rheumatoid arthritis, and multiple sclerosis. Through structure-based virtual screening, we identified a lupane-type pentacyclic triterpenoid, (2Z)-2-(2-furanylmethylene)-3-oxolup-20(29)-en-28-oic acid (), as a new inverse agonist of RORγ. The compound exhibited IC values of 0.4 μM and 0.9 μM in Gal4-RORγ and full-length RORγ luciferase assays, respectively. Compound showed improved potency and efficacy compared to a structurally related known inverse agonist, betulinic acid. Among the four additional analogues tested (-), two ( and ) also demonstrated RORγ inverse agonist activity with low micromolar IC values in Gal4-RORγ luciferase assay. Real-time quantitative polymerase chain reaction experiments confirmed that compounds , , and downregulated RORγ target genes. Thermal shift assays showed that both betulinic acid and stabilized the RORγ ligand-binding domain. Molecular docking and structure-activity relationship analysis revealed distinct binding modes within the RORγ ligand-binding domains, further supported by site-directed mutagenesis. These findings expand the repertoire of RORγ inverse agonists based on the pentacyclic triterpenoid scaffolds.
用反向激动剂靶向视黄酸相关孤儿受体γ（RORγ）是一种治疗自身免疫性疾病（包括银屑病、类风湿性关节炎和多发性硬化症）的有前景的治疗策略。通过基于结构的虚拟筛选，我们鉴定出一种羽扇烷型五环三萜类化合物，（2Z）-2-（2-呋喃基亚甲基）-3-氧代羽扇-20（29）-烯-28-酸（），作为一种新的RORγ反向激动剂。该化合物在Gal4-RORγ和全长RORγ荧光素酶测定中的IC值分别为0.4μM和0.9μM。与结构相关的已知反向激动剂桦木酸相比，化合物显示出更高的效力和功效。在测试的另外四种类似物（-）中，两种（和）在Gal4-RORγ荧光素酶测定中也表现出RORγ反向激动剂活性，IC值为低微摩尔浓度。实时定量聚合酶链反应实验证实化合物、和下调了RORγ靶基因。热位移测定表明桦木酸和都稳定了RORγ配体结合结构域。分子对接和构效关系分析揭示了RORγ配体结合结构域内不同的结合模式，定点诱变进一步支持了这一点。这些发现扩展了基于五环三萜支架的RORγ反向激动剂的种类。
