Mouse model for neuroprotection

神经保护小鼠模型

• 批准号: 7019332
• 负责人: GOPAL THINAKARAN
• 金额: $ 17.23万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-03-01 至 2008-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7019332
• 关键词: calcium flux; calcium ion; calcium metabolism; cerebral ischemia /hypoxia; cytoprotection; endoplasmic reticulum; genetically modified animals; glycoproteins; homeostasis; hormone regulation /control mechanism; hypercalcemia; laboratory mouse; neuroprotectants; tetracyclines; tissue /cell culture

DESCRIPTION (provided by applicant): Disturbance of Ca2+ homeostasis is a major cause of neuronal injury in transient ischemia and several neurodegenerative disorders such as Alzheimer's disease (AD), polyglutamine diseases, and Parkinson's disease. The endoplasmic reticulum (ER) is a major organelle for Ca2+ storage. The ER regulates multiple cellular functions through Ca2+ signaling, and provides a specialized environment for post-translational folding and maturation of transmembrane and luminal proteins. Loss of Ca2+ from intracellular stores causes elevation of cytosolic Ca2+, which can lead to neuronal vulnerability resulting from activation of intrinsic cell death pathways. In addition, since protein chaperones use Ca2+ as a cofactor, release of ER Ca2+ also causes cell injury through an accumulation of misfolded proteins. Physiological, pathological and experimental conditions that perturb ER function cause accumulation of misfolded proteins within the ER, and as a result of the ensuing ER stress, activate compensatory signaling pathways collectively known as the unfolded protein response (UPR). In this proposal we outline our strategy to develop a mouse model for neuroprotection against Ca2+ deregulation, based on overexpression of stanniocalcin 2 (STC2). We recently identified STC2 as a gene induced by the mammalian UPR, hypoxia, and cerebral ischemia. We further demonstrated that in cultured cells expression of STC2 is essential and sufficient to offer cytoprotection against cell death induced by disruption of ER Ca2+ homeostasis. STC2 is a secreted glycoprotein hormone highly conserved in fish and mammals. We postulate that STC2 carries out a distinct function in mammals as a critical survival component of the UPR, defending cells from injury caused by disruption of Ca2+ homeostasis under pathological conditions. The following are the specific aims of this proposal: Aim 1. To generate transgenic mice with spatial/temporal control of STC2 expression. Aim 2. To characterize the neuroprotective function of STC2. Our investigation will develop a valuable resource for the scientific community - transgenic mice with spatial and temporal control of STC2 expression, and perform in vitro and in vivo feasibility studies that will provide the proof of principle to demonstrate neuroprotective properties of STC2 against cell death initiated by deregulation of Ca2+ homeostasis. Outcome of our investigation will be critical for the future development of STC2 based therapeutic strategy to prevent neuronal death.

描述（由申请人提供）：Ca2+稳态紊乱是短暂性脑缺血和多种神经退行性疾病（如阿尔茨海默病（AD）、多聚谷氨酰胺疾病和帕金森病）中神经元损伤的主要原因。内质网 (ER) 是储存 Ca2+ 的主要细胞器。 ER 通过 Ca2+ 信号传导调节多种细胞功能，并为跨膜和腔蛋白的翻译后折叠和成熟提供专门的环境。细胞内储存的 Ca2+ 损失会导致胞质 Ca2+ 升高，从而导致内在细胞死亡途径激活导致神经元脆弱性。此外，由于蛋白质伴侣使用 Ca2+ 作为辅助因子，内质网 Ca2+ 的释放也会通过错误折叠蛋白质的积累而导致细胞损伤。扰乱 ER 功能的生理、病理和实验条件会导致 ER 内错误折叠蛋白的积累，并且由于随后的 ER 应激，激活代偿信号通路，统称为未折叠蛋白反应 (UPR)。在本提案中，我们概述了基于斯钙素 2 (STC2) 过度表达开发神经保护小鼠模型以防止 Ca2+ 失调的策略。我们最近发现STC2是由哺乳动物UPR、缺氧和脑缺血诱导的基因。我们进一步证明，在培养细胞中，STC2 的表达是必需的，足以提供细胞保护，防止因 ER Ca2+ 稳态破坏而诱导的细胞死亡。 STC2 是一种在鱼类和哺乳动物中高度保守的分泌型糖蛋白激素。我们假设 STC2 作为 UPR 的关键生存成分在哺乳动物中发挥着独特的功能，保护细胞免受病理条件下 Ca2+ 稳态破坏引起的损伤。该提案的具体目标如下： 目标 1. 产生具有 STC2 表达空间/时间控制的转基因小鼠。目标 2. 表征 STC2 的神经保护功能。我们的研究将为科学界开发一种宝贵的资源 - 具有 STC2 表达空间和时间控制的转基因小鼠，并进行体外和体内可行性研究，这将为证明 STC2 对 Ca2+ 稳态失调引起的细胞死亡的神经保护特性提供原理证明。我们的研究结果对于未来开发基于 STC2 的预防神经元死亡的治疗策略至关重要。