Calcineurin in pancreatitis

描述（由申请人提供）：急性胰腺炎是一种痛苦的、危及生命的疾病，目前尚无靶向治疗方法。我们和其他人已经表明，胰腺腺泡细胞内的病理性钙信号启动早期胰腺炎反应。此外，我们假设钙依赖性丝氨酸、苏氨酸磷酸酶钙调磷酸酶（CN）是这种病理性钙信号的新靶点。因此，我们建议使用遗传学和药理学策略来（目的1）检验CN在临床相关的胰腺炎实验模型中的作用[1a，胆汁酸导管内输注；1 b, post-ERCP;1c，酒精致敏]，以（目标2）确定在分离的腺泡细胞中，使用CN抑制剂、腺病毒转染CN构建物和来自CN转基因的细胞来确定腺泡细胞CN对胰腺炎的贡献，以及（目标3）在体内使用可诱导的、腺泡细胞特异性CN转基因（内源性降低CN活性或删除CN）。我们的初步数据支持我们的假设和计划研究的可行性，表明在导管内胆汁输注的体内模型中，用CN抑制剂FK506或CN基因缺陷（CN A2 KOs）治疗的小鼠显着降低了胰腺炎的严重程度。我们还表明，在使用化学CN抑制的分离的腺泡细胞或CN缺陷小鼠的细胞中，腺泡内蛋白酶活性降低。预计这些研究(1)将为理解钙磷酸酶CN在各种形式的胰腺炎中的作用提供基础，(2)将为使用CN抑制剂靶向胰腺炎的新型临床试验奠定框架。

DESCRIPTION (provided by applicant): Acute pancreatitis is a painful, life-threatening disorder for which there are no targeted therapies. We and others have shown that pathologic calcium signals within the pancreatic acinar cell initiate early pancreatitis responses. Further, we have hypothesized that the calcium-dependent serine, threonine phosphatase calcineurin (CN) is a novel target of this pathological calcium signal. Thus, we propose to use genetic and pharmacologic strategies to (Aim 1) examine the role of CN in clinically relevant experimental models of pancreatitis in vivo [1a, intra-ductal bile acid infusion; 1b, post-ERCP; 1c, alcohol sensitized], to (Aim 2) determine the contribution of acinar cell CN to pancreatitis in isolated acinar cells using CN inhibitors, adenoviral transfection of CN constructs, and cells from CN transgenics, as well as (Aim 3) in vivo using inducible, acinar cell specific CN transgenics that either endogenously reduce CN activity or delete CN. Our preliminary data support our hypothesis and the feasibility of the planned studies by showing that mice either treated with the CN inhibitor FK506 or genetically deficient in CN (CN A2 KOs) have markedly reduced pancreatitis severity in an in vivo model of intra-ductal bile infusion. We also show that in isolated acinar cells using chemical CN inhibition or cells from CN deficient mice that intra-acinar protease activation is reduced. It is anticipated that these studies (1) will provide a basis for understanding the role of the calcium phosphatase CN in various forms of pancreatitis and (2) will lay the framework for novel clinical trials that target pancreatitis using CN inhibitors. PUBLIC HEALTH RELEVANCE: Acute pancreatitis is a painful and life-threatening disease of the pancreas for which we have no specific treatments. Based on the fact that calcium signals within the pancreas are required for pancreatitis to occur, our proposal seeks to examine the role of an important calcium target protein called calcineurin. We will use animal models of pancreatitis that mimic three common human causes, namely, gallstones, alcohol abuse, and a complication of an endoscopic procedure called an ERCP. We are hopeful that our studies will lead to clinical trials that test the use of already available calcineurin blocking drugs for the treatment of pancreatitis.