Characterization of hepatocyte growth factor activator inhibitors which are being developed for a medicine

正在开发的药物肝细胞生长因子激活剂抑制剂的表征

基本信息

批准号：
13557012
负责人：
KITAMURA Naomi
金额：
$ 8.9万
依托单位：
TOKYO INSTITUTE OF TECHNOLOGY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

It is reported that overaction of hepatocyte growth factor (HGF) causes kidney injury. Thus, it is required to develop a medicine which suppresses overaction of HGF. We identified two novel protease inhibitors (HAI-1 and HAI-2) which inhibit the activity of HGF activator. In this study, we examined whether these inhibitors could function as a medicine for diseases caused by overaction of HGF, and obtained the following results.1. HAI-1 has two Kunitz domains which are thought to be functional domains for the protease inhibitory activity of HAI-1. To determine the roles of the Kunitz domains in the inhibitory activity of HAI-1 against HGF activator, we constructed various human HAI-1 mutant proteins and examined their inhibitory activity against HGF activator. The N-terminal Kunitz domain had potent inhibitory activity, whereas the C-terminal Kunitz domain had only very weak activity. HAI-2 also has two Kunitz domains. We also examined the roles of Kunitz domains in the inhibitory activity of mouse HAI-2 against HGF activator. Unlike human HAI-1, the C-terminal Kunitz domain had potent inhibitory activity, whereas the N-terminal Kunitz domain had less activity. Therefore, it is necessary to examine which Kunitz domain of HAI-1 and HAI-2 is suitable for a medicine.2. To investigate whether the Kunitz domain of HAI suppresses activation of HGF in vivo, it is required to establish an assay system using experimental animals. We examined whether injection of HGF activator into rats induces activation of HGF. Injection of HGF activator induced activation of HGF in the liver of partially hepatectomized rats. This injection also induced liver regeneration. Therefore, this system would be useful to assay the inhibitory activity of the Kunitz domain of HAI.

据报道，肝细胞生长因子（HGF）的过度作用会导致肾损伤。因此，需要开发一种抑制HGF过度作用的药物。我们鉴定了两种新型蛋白酶抑制剂（HAI-1 和 HAI-2），它们可抑制 HGF 激活剂的活性。在本研究中，我们检验了这些抑制剂是否可以作为治疗HGF过度作用引起的疾病的药物，并获得以下结果： 1． HAI-1 具有两个 Kunitz 结构域，这两个结构域被认为是 HAI-1 蛋白酶抑制活性的功能结构域。为了确定 Kunitz 结构域在 HAI-1 对 HGF 激活剂的抑制活性中的作用，我们构建了各种人 HAI-1 突变蛋白并检查了它们对 HGF 激活剂的抑制活性。 N端Kunitz结构域具有有效的抑制活性，而C端Kunitz结构域仅具有非常弱的活性。 HAI-2 还有两个 Kunitz 域。我们还研究了 Kunitz 结构域在小鼠 HAI-2 对 HGF 激活剂的抑制活性中的作用。与人类 HAI-1 不同，C 端 Kunitz 结构域具有有效的抑制活性，而 N 端 Kunitz 结构域的活性较低。因此，有必要考察HAI-1和HAI-2的Kunitz结构域中哪个Kunitz结构域适合作为药物。2．为了研究HAI的Kunitz结构域是否在体内抑制HGF的激活，需要建立使用实验动物的检测系统。我们检查了向大鼠注射 HGF 激活剂是否会诱导 HGF 激活。注射 HGF 激活剂可诱导部分肝切除大鼠肝脏中 HGF 的激活。这种注射还诱导肝脏再生。因此，该系统可用于测定 HAI 的 Kunitz 结构域的抑制活性。