The Role of Trypsin in Pancreatitis

胰蛋白酶在胰腺炎中的作用

• 批准号: 7195516
• 负责人: Baoan Ji
• 金额: $ 18.75万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7195516
• 关键词: Acinar Cell; Acute; Address; Adenoviruses; Animal Disease Models; Animal Model; Cells; DNA Binding; Development; Disease; Dose; Elastases; Enzyme Precursors; Enzymes; Event; Functional disorder; Gene Activation; Gene Transfer; Goals; Green Fluorescent Proteins; In Vitro; Inflammatory; Inherited; Inhibition of NF-KB activation; Measures; Modeling; Mutation; Pancreas; Pancreatic Elastase; Pancreatic Injury; Pancreatitis; Patients; Phosphorylation; Process; Purpose; Rattus; Research Personnel; Role; Severities; Signal Pathway; Signal Transduction; Site; Tamoxifen; Testing; Time; Tissues; Transgenic Mice; Trypsin; Trypsin Inhibitors; Trypsinogen; Virus; acute pancreatitis; adenoviral-mediated; chronic pancreatitis; enteropeptidase; improved; in vivo; mutant; novel; programs; promoter

DESCRIPTION (provided by applicant): The central goal of this proposal is to establish and characterize novel models of acute and chronic pancreatitis by direct intra-acinar cell trypsinogen activation. Recent discoveries of trypsinogen and trypsin inhibitor mutations in patients with hereditary pancreatitis support the hypothesis that an inappropriate activation of pancreatic zymogens to active enzymes within the pancreas starts the inflammatory process. Thus premature activation of trypsin is believed to be the initial step in the development of pancreatitis. However, current animal models of acute pancreatitis involve treatments that have many non-specific effects and trigger numerous signaling pathways in addition to activating trypsin. The situation for chronic pancreatitis is even less clear, as there are no reliable animal models of this disease. Specific aim #1 is to induce acute pancreatitis by direct trypsin activation within pancreatic acinar cells in rats. We will initially use adenoviral mediated gene transfer into the rat pancreas of a mutant trypsinogen (AdPACE-TRY) which we developed and have shown to become activated within the acinar cells. We hypothesize that delivery of this virus to the pancreas in vivo will active trypsin and thereby initiate pancreatitis. Specific aim #2 is to determine whether intracellular trypsin induces NF-KB activation and the role of NF-KB in trypsin induced acute pancreatitis. We have previously shown that NF-KB activation does not cause trypsinogen activation. Here we will test if trypsin activity within the acinar cell can activate NF-KB using AdPACE-TRY to activate trypsin intracellularly and investigate the mechanisms involved. We will further examine the importance of trypsin activation of NF-KB in the initiation of the inflammatory cascade by co-administering an adenovirus expressing kB-cc which will block NF-KB activation. Specific aim #3 is to establish a chronic pancreatitis model by directly regulating intra-acinar trypsin activity. We will create a chronic pancreatitis model by directly regulating intra-acinar trypsin activity. For this purpose, an elastase promoter driven tamoxifen regulatable Cre-Er transgenic mouse will be crossed with a loxP- GFP flanked PACE-TRY transgenic mouse. Tamoxifen activation of Cre will then remove a stop sequence allowing the expression of the active trypsin. We expect that a high dose tamoxifen will induce high trypsin activity and thus cause severe acute pancreatitis and that a low dose tamoxifen will induce partially pancreatic injury and prolonged pancreatic damage that will result in chronic pancreatitis.

描述（由申请方提供）：本提案的中心目标是通过直接腺泡内细胞胰蛋白酶原激活建立和表征急性和慢性胰腺炎的新型模型。最近在遗传性胰腺炎患者中发现胰蛋白酶原和胰蛋白酶抑制剂突变，这支持了胰腺内胰腺酶原不适当地激活为活性酶启动炎症过程的假设。因此，胰蛋白酶的过早激活被认为是胰腺炎发展的初始步骤。然而，目前的急性胰腺炎动物模型涉及具有许多非特异性作用的治疗，并且除了激活胰蛋白酶之外还触发许多信号传导途径。慢性胰腺炎的情况甚至更不清楚，因为没有可靠的这种疾病的动物模型。具体目标#1是通过在大鼠胰腺腺泡细胞内直接激活胰蛋白酶来诱导急性胰腺炎。我们将首先使用腺病毒介导的基因转移到大鼠胰腺的突变胰蛋白酶原（AdPACE-TRY），我们开发并已被证明成为激活的腺泡细胞内。我们推测，这种病毒在体内传递到胰腺将激活胰蛋白酶，从而引发胰腺炎。具体目标#2是确定细胞内胰蛋白酶是否诱导NF-κ B活化以及NF-κ B在胰蛋白酶诱导的急性胰腺炎中的作用。我们先前已经证明NF-κ B激活不会引起胰蛋白酶原激活。在这里，我们将测试腺泡细胞内的胰蛋白酶活性是否可以使用AdPACE-TRY激活细胞内的胰蛋白酶激活NF-κ B，并研究所涉及的机制。我们将通过共同施用表达kB-a的腺病毒（其将阻断NF-κ B活化）来进一步检查NF-κ B的胰蛋白酶活化在炎症级联反应的起始中的重要性。具体目标#3是通过直接调节腺泡内胰蛋白酶活性来建立慢性胰腺炎模型。我们将通过直接调节腺泡内胰蛋白酶活性来建立慢性胰腺炎模型。为此目的，将弹性蛋白酶启动子驱动的他莫昔芬可调节的Cre-Er转基因小鼠与loxP-GFP侧翼的PACE-TRY转基因小鼠杂交。他莫昔芬激活Cre然后将去除终止序列，从而允许活性胰蛋白酶的表达。我们预期高剂量的他莫昔芬将诱导高胰蛋白酶活性，从而引起重症急性胰腺炎，低剂量的他莫昔芬将诱导部分胰腺损伤和长期胰腺损伤，这将导致慢性胰腺炎。