The Role of Caspases in Warm and Cold Ischemia

Caspases 在热缺血和冷缺血中的作用

• 批准号: 7036973
• 负责人: Alkesh Harihar Jani
• 金额: $ 13.11万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-15 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7036973
• 关键词: apoptosis; brush border membrane; cysteine endopeptidases; cytochrome c; enzyme activity; gene expression; genetically modified animals; histocompatibility antigens; immunocytochemistry; interferon gamma; interleukin 18; kidney disorder; kidney function; kidney transplantation; laboratory mouse; morphology; protein structure function; renal ischemia /hypoxia; renal tubule; terminal nick end labeling; western blottings

DESCRIPTION (provided by applicant): Delayed graft function (DGF) independently predicts reduced 1- and 5- year kidney transplant survival and contributes to the development of chronic allograft nephropathy (CAN). DGF is caused by both cold and warm ischemia. Cold ischemia occurs during both pulsatile machine perfusion and static cold storage of kidneys. This grant will focus on the pathophysiology of cold and warm ischemia and specifically the role of caspases. Caspase-3 is a major mediator of apoptotic and necrotic cell death. Caspase-1 converts the proinflammatory cytokines IL-1beta and IL-18 to their active forms. The overall hypothesis is that caspases mediate proximal tubular damage in both cold and warm ischemia. In a model of cold ischemia the contribution of caspase-3 to proximal tubular apoptosis as well as severe brush border injury will be assessed. Gene expression, protein and activity of caspases-3, 7, 9 (mitochondrial pathway of apoptosis) and 8 (death receptor pathway of apoptosis) will be determined during both static and pulsatile cold ischemia. Immunohistochemistry for activated caspase-3 in proximal tubules will be performed. The effect of caspase inhibition on kidney morphology will be assessed. The findings of these experiments will contribute to the understanding of cold ischemia injury and organ preservation. Caspase-1-mediated production of IL-18 mediates ischemic ARF. IL-18 is a potent inducer of interferon gamma, which is a powerful inducer of MHC expression. Caspase-1 and IL-18-mediated increase in interferon gamma expression in the kidney and MHC expression on proximal tubules will be determined in a model of warm ischemia. Interferon gamma and MHC class I and II mRNA expression in the kidney will be assessed. The effect of caspase-1, IL-18 and interferon gamma inhibition on MHC expression will be evaluated. Reduced MHC expression is associated with decreased kidney graft immunogenicity and has important implications for the deleterious effect of DGF on both short and long-term allograft function

描述（由申请人提供）： 移植物功能延迟 (DGF) 独立预测肾移植 1 年和 5 年存活率降低，并导致慢性同种异体移植肾病 (CAN) 的发展。 DGF 是由冷缺血和热缺血引起的。肾脏的脉动机器灌注和静态冷藏期间都会发生冷缺血。这笔资金将重点研究冷缺血和热缺血的病理生理学，特别是半胱天冬酶的作用。 Caspase-3 是细胞凋亡和坏死性细胞死亡的主要介质。 Caspase-1 将促炎细胞因子 IL-1beta 和 IL-18 转化为其活性形式。总体假设是半胱天冬酶在冷缺血和热缺血中介导近端肾小管损伤。在冷缺血模型中，将评估 caspase-3 对近端肾小管细胞凋亡以及严重刷状缘损伤的贡献。在静态和脉冲冷缺血期间，将测定 caspase-3、7、9（凋亡的线粒体途径）和 8（凋亡的死亡受体途径）的基因表达、蛋白质和活性。将进行近曲小管中活化的 caspase-3 的免疫组织化学分析。将评估半胱天冬酶抑制对肾脏形态的影响。这些实验的结果将有助于了解冷缺血损伤和器官保存。 Caspase-1 介导的 IL-18 产生介导缺血性 ARF。 IL-18 是干扰素 γ 的有效诱导剂，干扰素 γ 是 MHC 表达的强大诱导剂。 Caspase-1 和 IL-18 介导的肾脏中干扰素 γ 表达和近端小管上 MHC 表达的增加将在热缺血模型中测定。将评估肾脏中的干扰素 γ 以及 MHC I 类和 II 类 mRNA 表达。将评估 caspase-1、IL-18 和干扰素 γ 抑制对 MHC 表达的影响。 MHC 表达减少与肾移植物免疫原性降低有关，并且对 DGF 对短期和长期同种异体移植物功能的有害影响具有重要意义