Exocrine pancreatic zymogen activation

外分泌胰腺酶原激活

基本信息

批准号：
9244026
负责人：
Fred Sanford Gorelick
金额：
$ 22.78万
依托单位：
YALE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
1998
资助国家：
美国
起止时间：
1998-07-15 至 2019-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9244026
关键词：
5&apos -AMP-activated protein kinase Acinar Cell Acinus organ component Affect Apical Blood flow Calcium Catalytic Domain Cause of Death Cell Death Clinical Co-Immunoprecipitations Data Development Disease Drug Targeting Drug usage Effectiveness Enzyme Activation Enzyme Precursors Enzymes Exocrine pancreas Exposure to Genetic Hand Human Inflammation Inflammation Mediators Inflammatory Injury Islets of Langerhans Transplantation Knockout Mice Knowledge Lead Link Mediator of activation protein Metformin Modeling Molecular Target Mus Pancreas Pancreatic Diseases Pancreatitis Pathologic Pathway interactions Perfusion Pharmaceutical Preparations Phase Phosphorylation Preparation Process Protein Isoforms Protein Kinase Protein Kinase C Publications Publishing Rattus Reporting Rodent Role SRC gene Salicylic Acids Severities Severity of illness Signal Transduction Signaling Molecule Small Interfering RNA Therapeutic Time Trypsinogen acute pancreatitis base cellular targeting in vivo in vivo Model knock-down novel therapeutics prevent protective effect public health relevance response therapeutic target vacuolar H+-ATPase

项目摘要

DESCRIPTION (provided by applicant): Acute pancreatitis, an inflammatory disease of the pancreas, causes death in over 30% of those with severe disease. Specific therapies to prevent pancreatitis or reduce injury are lacking. The disease is thought to begin in the pancreatic acinar cell after exposure to insults that initiate pathologic changes in this cell's signaling. Subsequen pathologic acinar cell responses are followed by changes in blood flow, inflammation, and cell death. We propose to examine a previously undescribed mediator of intracellular signaling that modulates pancreatitis responses, AMP-regulated protein kinase (AMPK). The enzyme may be an attractive therapeutic target. Based on our preliminary findings and recent publication, we hypothesize that AMPK serves a protective role in pancreatitis within the acinar cell and does so by inhibiting key mediators of pancreatitis, including the vacuolar ATPase (vATPase). Further, its protective role appears to be reduced in the acinar cell during the early phases of pancreatiti when AMPK activity rapidly decreases in selective cellular compartments. In preliminary studies, the proposed protective role for AMPK was supported by findings in cellular and in vivo pancreatitis models which showed that: a) clinically used drugs that can activate AMPK reduce disease severity, b) genetically reducing AMPK using either siRNA in pancreatic acini (groups of 20-100 acinar cells) or a knockout mouse lacking the essential AMPK alpha-1 subunit, increases the severity of pancreatitis. Finally, preliminary studies indicate that human acinar cells contain AMPK and have an essential subunit isoform (beta-1) that is required for drug targeting. To examine the role of AMPK in pancreatitis, the following Specific Aims are planned: 1) Examine agents that activate AMPK in isolated pancreatic acini, 2) Examine agents that activate AMPK using in vivo models of pancreatitis, and 3) Determine the molecular and cellular targets of AMPK. Studies will be carried out with isolated groups of pancreatic acinar cells (acini) and in vivo pancreatitis models that produce mild and severe disease. Effects observed in isolated rodent acinar cells will be confirmed in a similar preparation of human acinar cells. Genetic knockdown of AMPK in acini has been performed and intact mice with deletions of AMPK's catalytic subunits are on hand and will be used to confirm AMPK's role in pancreatitis and to show that drugs found to reduce disease severity are acting through AMPK. The effects of AMPK activating drugs on AMPK translocation and downstream processes such as vATPase activation will be examined. We have identified AMPK activators that are currently available medications with safe profiles that also decrease the severity of acute pancreatitis in our models. Thus, the proposed studies have strong translational and therapeutic potential.

描述（由申请人提供）：急性胰腺炎是一种胰腺炎症性疾病，导致 30% 以上的重症患者死亡。目前缺乏预防胰腺炎或减少损伤的具体疗法。这种疾病被认为始于胰腺腺泡细胞受到损伤后，会引发该细胞信号传导的病理变化。随后的病理性腺泡细胞反应是血流变化、炎症和细胞死亡。我们建议检查一种以前未描述过的调节胰腺炎反应的细胞内信号传导介质，即 AMP 调节蛋白激酶 (AMPK)。该酶可能是一个有吸引力的治疗靶点。根据我们的初步研究结果和最近发表的文章，我们假设 AMPK 在腺泡细胞内的胰腺炎中发挥保护作用，并通过抑制胰腺炎的关键介质（包括液泡 ATP 酶（vATP 酶））来实现这一作用。此外，在胰腺炎的早期阶段，当选择性细胞区室中 AMPK 活性迅速降低时，其在腺泡细胞中的保护作用似乎会减弱。在初步研究中，所提出的 AMPK 保护作用得到了细胞和体内胰腺炎模型中的发现的支持，该模型表明：a）临床使用的可激活 AMPK 的药物可减轻疾病的严重程度，b）在胰腺腺泡中使用 siRNA 从基因上减少 AMPK（ 20-100 个腺泡细胞组）或缺乏必需 AMPK α-1 亚基的基因敲除小鼠，会增加胰腺炎的严重程度。最后，初步研究表明，人类腺泡细胞含有 AMPK，并具有药物靶向所需的重要亚基异构体 (β-1)。为了检查 AMPK 在胰腺炎中的作用，计划实现以下具体目标：1) 检查在分离的胰腺腺泡中激活 AMPK 的药物，2) 使用胰腺炎体内模型检查激活 AMPK 的药物，以及 3) 确定分子和细胞AMPK 的目标。研究将使用分离的胰腺腺泡细胞（acini）组和产生轻度和重度疾病的体内胰腺炎模型进行。在分离的啮齿动物腺泡细胞中观察到的效果将在人类腺泡细胞的类似制剂中得到证实。腺泡中 AMPK 的基因敲除已经完成，并且已经有了 AMPK 催化亚基缺失的完整小鼠，这些小鼠将用于证实 AMPK 在胰腺炎中的作用，并表明减轻疾病严重程度的药物是通过 AMPK 发挥作用的。将检查 AMPK 激活药物对 AMPK 易位和下游过程（例如 vATP 酶激活）的影响。我们已经确定了 AMPK 激活剂，它们是目前可用的具有安全特性的药物，也可以降低我们模型中急性胰腺炎的严重程度。因此，拟议的研究具有强大的转化和治疗潜力。