Abstract

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world, whose pathologic features include dysregulated glucose homeostasis and lipid accumulation. Peroxisome proliferators-activated receptor α (PPARα) is a key regulator of fatty acid metabolism and ketogenesis due to its regulatory pathways involve activating fatty acid uptake, accelerating fatty acid oxidation, inhibiting gluconeogenesis, and suppressing inflammation and fibrosis. Therefore, PPARα is considered as a potential target for the treatment of NAFLD and some agonists have entered clinical trials, which drove us to discover more novel PPARα agonists. In current work, new 3H-benzo[b] [1,4] diazepine PPARα agonists were identified from the ChemDiv database by pharmacophore modeling, molecular docking, derivative structure search, and bioassays, where compound LY-2 and its derivatives (LY-10∼LY-19) were discovered to promote the expression of PPARα downstream gene, carnitine palmitoyl transterase-1 α (cpt1α). Among these active compounds, the EC₅₀ value of LY-2 against increasing cpt1α was 2.169 μΜ. Furthermore, the effect of LY-2 on cpt1α was weakened when PPARα knock down, which confirmed that it is a PPARα agonist again. Finally, the results from molecular dynamics simulations and binding free energy calculations showed that π-π stacking and hydrogen bonding interactions played key roles in the binding of LY-2 and PPARα protein and their complex maintained a stable structure to facilitate LY-2 to have a better binding affinity with PPARα protein. Taken together, compound LY-2 might be a novel lead compound for the development of potent PPARα agonists.

Communicated by Ramaswamy H. Sarma

摘要

非酒精性脂肪肝病（NAFLD）是世界上最常见的慢性肝病，其病理特征包括葡萄糖稳态失调和脂质积累。过氧化物酶体增殖物激活受体α（PPARα）是脂肪酸代谢和生酮的关键调节因子，因为其调节途径涉及激活脂肪酸摄取、加速脂肪酸氧化、抑制糖异生以及抑制炎症和纤维化。因此，PPARα被认为是治疗NAFLD的潜在靶点，并且一些激动剂已经进入临床试验，这促使我们发现更多新型的PPARα激动剂。目前的工作中，通过药效团建模、分子对接、衍生结构搜索和生物测定，从 ChemDiv 数据库中鉴定出新的 3H-苯并[b] [1,4]二氮杂 PPARα 激动剂，其中化合物 LY-2 及其衍生物（LY- 10∼LY-19)被发现可以促进PPARα下游基因肉毒碱棕榈酰转移酶-1α(cpt1α)的表达。在这些活性化合物中，LY-2针对增加的cpt1α的EC ₅₀值为2.169μM。此外，当PPARα敲低时，LY-2对cpt1α的作用减弱，这再次证实了LY-2是PPARα激动剂。最后，分子动力学模拟和结合自由能计算结果表明，π-π堆积和氢键相互作用在LY-2和PPARα蛋白的结合中发挥了关键作用，并且它们的复合物保持了稳定的结构，有利于LY-2具有与 PPARα 蛋白有更好的结合亲和力。综上所述，化合物 LY-2 可能是开发强效 PPARα 激动剂的新型先导化合物。

拉马斯瓦米·萨尔马 (Ramaswamy H. Sarma) 通讯