Molecular Pathomechanism of Hereditary Pancreatitis

遗传性胰腺炎的分子病理机制

• 批准号: 7052760
• 负责人: Miklos Sahin-Toth
• 金额: $ 29.1万
• 依托单位: BOSTON UNIVERSITY MEDICAL CAMPUS
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-05-01 至 2010-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7052760
• 关键词: SDS polyacrylamide gel electrophoresis; anions; cathepsin B; disease /disorder model; genetic disorder; genetic polymorphism; model design /development; mutant; pancreatitis; protein degradation; protein structure function; trypsin; zymogens

DESCRIPTION (provided by applicant): The broad, long-term objectives of this grant-proposal are to understand the molecular mechanisms of human pancreatitis using hereditary pancreatitis and other forms of genetically determined pancreatitis as biochemical models. The most frequently found mutations in genetic pancreatitis affect the PRSS1 gene that codes for human cationic trypsinogen and the SPINK1 gene encoding pancreatic secretory trypsin inhibitor. In the previous funding period our laboratory has developed methodology for the in vitro study of human trypsinogen mutations and through characterization of several pancreatitis-associated mutants we have formulated a working hypothesis. This model states that elevated intraacinar trypsin activity is the fundamental initiating step of genetic pancreatitis and trypsinogen mutations generally exert this effect through increased autocatalytic activation. In the present proposal we seek to extend our mechanistic model, and prove that increased trypsin activity plays the central role in all forms of genetic pancreatitis. The following specific aims will be studied. (1) The role of human mesotrypsin in pancreatitis. Mesotrypsin is a unique protease specialized for the degradation of trypsin inhibitors. Premature mesotrypsinogen activation might lower protective SPINK1 levels in the pancreas and contribute to the pathogenesis of pancreatitis. (2) Characterization of pancreatitis-associated cationic trypsinogen (PRSS1) mutants. Identification of novel mutation-dependent biochemical defects will allow us to refine our model of molecular pathogenesis. (3) Functional analysis of novel anionic trypsinogen (PRSS2) mutants that afford protection against pancreatitis. The concept that loss-of-function trypsinogen mutations can protect against pancreatitis provides independent evidence for the central role of trypsin in this disease. (4) Identification of the disease-causing biochemical defects in pancreatitis-associated SPINK1 mutants.

描述（由申请人提供）：这种赠款权利的广泛，长期目标是使用遗传性胰腺炎和其他形式的遗传确定的胰腺炎作为生化模型来了解人类胰腺炎的分子机制。遗传胰腺炎中最常见的突变会影响编码人阳离子胰蛋白酶原和编码胰腺分泌胰蛋白酶抑制剂的Spink1基因的PRSS1基因。在上一个资金期间，我们的实验室开发了对人胰蛋白酶原突变的体外研究的方法论，并通过表征了几个胰腺炎相关突变体，我们提出了一个有效的假设。该模型指出，较高的素内胰蛋白酶活性是遗传胰腺炎和胰蛋白酶原突变的基本启动步骤，通常通过增加的自催化激活来发挥这种作用。在本提案中，我们试图扩展机械模型，并证明增加胰蛋白酶活性在各种形式的遗传胰腺炎中起着核心作用。将研究以下特定目标。 （1）人类性丙吡啶蛋白酶在胰腺炎中的作用。美索丙吡啶蛋白酶是一种独特的蛋白酶，专门用于胰蛋白酶抑制剂降解。过早的间替蛋白酶原激活可能会降低胰腺中的保护性Spink1水平，并导致胰腺炎的发病机理。 （2）表征胰腺炎相关的阳离子胰蛋白酶原（PRSS1）突变体。鉴定新型突变依赖性生化缺陷将使我们能够完善分子发病机理模型。 （3）对胰腺炎进行保护的新型阴离子胰蛋白酶原（PRSS2）突变体的功能分析。功能丧失胰蛋白酶原突变可以预防胰腺炎的概念为胰蛋白酶在该疾病中的核心作用提供了独立的证据。 （4）鉴定胰腺炎相关的Spink1突变体中引起疾病​​的生化缺陷。