Izuhara Yuko, Takahashi Satoru, Nangaku Masaomi, Takizawa Shunya, Ishida Hideyuki, Kurokawa Kiyoshi, van Ypersele de Strihou Charles, Hirayama Noriaki, Miyata Toshio
Institute of Medical Sciences, Tokai University, Kanagawa, Japan
Arterioscler Thromb Vasc Biol. 2008 Apr;28(4):672-7. doi: 10.1161/ATVBAHA.107.157479. Epub 2008 Jan 31.
Serine protease inhibitors (serpin) play a central role in various pathological processes including coagulation, fibrinolysis, malignancy, and inflammation. Inhibition of serpins may prove therapeutic. As yet, however, only very few small molecule serpin inhibitors have been reported. For the first time, we apply a new approach of virtual screening to discover novel, orally active, small molecule serpin inhibitors and report their effectiveness.
We focused on a clinically important serpin, plasminogen activator inhibitor-1 (PAI-1), whose crystal structure has been described. We identify novel, orally active molecules able to enter into the strand 4 position (s4A) of the A beta-sheet of PAI-I as a mock compound. In vitro they specifically inhibit the PAI-1 activity and enhance fibrinolysis activity. In vivo the most effective molecule (TM5007) inhibits coagulation in 2 models: a rat arteriovenous (AV) shunt model and a mouse model of ferric chloride-induced testicular artery thrombosis. It also prevents the fibrotic process initiated by bleomycin in mouse lung.
The present study demonstrates beneficial in vitro and in vivo effects of novel PAI-1 inhibitors. Our methodology proves to be a useful tool to obtain effective inhibitors of serpin activity.
丝氨酸蛋白酶抑制剂（serpin）在包括凝血、纤维蛋白溶解、恶性肿瘤和炎症等多种病理过程中发挥核心作用。抑制serpin可能具有治疗作用。然而，迄今为止，仅有极少数小分子serpin抑制剂被报道。我们首次应用一种新的虚拟筛选方法来发现新型、口服活性小分子serpin抑制剂并报告其有效性。
我们聚焦于一种临床重要的serpin，即纤溶酶原激活物抑制剂-1（PAI-1），其晶体结构已被描述。我们鉴定出能够作为模拟化合物进入PAI-1的Aβ-折叠的4号链位置（s4A）的新型口服活性分子。在体外，它们特异性抑制PAI-1活性并增强纤维蛋白溶解活性。在体内，最有效的分子（TM5007）在两种模型中抑制凝血：大鼠动静脉（AV）分流模型和氯化铁诱导的小鼠睾丸动脉血栓形成模型。它还能预防博来霉素在小鼠肺中引发的纤维化过程。
本研究证明了新型PAI-1抑制剂在体外和体内的有益作用。我们的方法被证明是获得serpin活性有效抑制剂的有用工具。
