PGI2 IP receptor role in global ischemia in young and aged mice

描述(申请人提供)：中风是导致西方人口死亡和长期残疾的第三大原因。类似的损伤在成人中的结果比在年轻人中更糟糕，但这种差异背后的机制尚不清楚。我在这里的主要目标是找出临床上相关的PGI2作为炎症过程的调节器在老年和年轻小鼠的全脑缺血小鼠模型中的重要性，以解决这个问题。一个在分子和行为神经科学方面具有神经学专长的跨学科研究团队和神经病理学家将解决以下假说：与WT小鼠相比，老年前列环素受体(PGI2)(IP)KO因全脑缺血引起的炎症反应增加将恶化学习记忆能力，减少局部脑血流量(RCBF)，增加白细胞渗透和海马神经细胞死亡。这些实验测试了特定的假设，即在老年小鼠中，增强的炎症反应会导致全脑缺血后磷酸化CREB和CREB水平的下降。初步数据显示，与WT小鼠相比，IP KO小鼠的学习和记忆能力降低，海马细胞死亡增加，这一假说。提出了四个特定的目标来验证这些假说：1)确定与年轻小鼠(2-3月龄)相比，PGI2(IP)受体的基因缺失是否会加剧C57BL6老年小鼠(12-15月龄)的神经行为缺陷和神经细胞死亡。2)确定与其对照相比，老年IP-/-小鼠是否会观察到绝对rCBF减少和白细胞浸润增加。3)确定IP激动剂是否改善WT小鼠全脑缺血后的学习记忆能力，拮抗剂是否降低WT小鼠的学习记忆能力。4)采用免疫组织化学方法检测全脑缺血后1h、3h、1、4、7d不同时间点脑组织中磷酸化CREB和CREB水平，以确定神经元死亡情况，并探讨其作用机制。这些新的临床相关药物的开发可能会为治疗全脑缺血和潜在的其他神经退行性疾病提供一种新的治疗策略。这项研究建议通过开发治疗性的PGI2(IP)受体刺激药物来改善老年人的学习和记忆，并控制老年人心脏骤停引起的脑损伤，将具有直接的临床前意义。

DESCRIPTION (provided by applicant): Stroke is the third leading cause of death and long-term disability in the Western population. The results of a similar injury are worse in the adults than in young people, but the mechanisms underlying this difference are unknown. My main goal here is to find out the importance of clinically relevant PGI2 as a modulator of the inflammatory process, in global cerebral ischemia mouse model in old and young mice to address this question. An interdisciplinary research team with neurologist expertise in molecular and behavioral neuroscience and neuropathologist will address the hypotheses that increased inflammatory response due to global cerebral ischemia in older prostacyclin receptor ( PGI2) (IP) KO will worsen the learning and memory performance, decrease regional cerebral blood flow (rCBF), increase leukocyte infiltration and hippocampal neuronal cell death as compared to WT mice. The experiments test the specific hypothesis that in old mice, an enhanced inflammatory response results in decrease in phospho CREB and CREB levels after global cerebral ischemia. Preliminary data this hypothesis by demonstrating reduced learning and memory performance and increased hippocampal cell death in IP KO mice as compared to WT mice. Four specific aims are proposed to test these hypotheses: 1) Determine whether genetic deletion of PGI2 (IP) receptor will aggravate neurobehavioral deficit and neuronal cell death in C57Bl6 older mice (12-15 months old) as compared to younger mice (2-3 months old). 2) Determine whether attenuated absolute rCBF and increased leukocyte infiltration will be observed in older IP-/- as compared to young mice as compared to their controls. 3) Determines whether IP agonists improve and antagonists reduce learning and memory performance after global cerebral ischemia in WT mice. 4) Determine the neuronal cell death by performing immunohistochemistry and find out the mechanism of actions by investigating the phospho-CREB and CREB level at different time points- 1h, 3h and 1, 4 and 7d after global cerebral ischemia. Development of these novel clinically relevant drugs could provide a new therapeutic strategy against global cerebral ischemia and potentially other neurodegenerative disorders. This research proposal will have direct pre-clinical importance by developing therapeutic PGI2 (IP) receptor stimulating drugs to improve learning and memory and controlling brain damage induced by cardiac arrest in elderly people.