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

描述（由申请人提供）：中风是西方人口死亡和长期残疾的第三大原因。类似损伤的结果在成年人中比在年轻人中更严重，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相关的PGI2作为炎症过程调节剂的重要性，在老年和年轻小鼠的全脑缺血小鼠模型中解决这个问题。一个由分子和行为神经科学和神经病理学专家组成的跨学科研究小组将解决这样的假设：与WT小鼠相比，老年前列腺环素受体（PGI2） （IP） KO由于全局性脑缺血而增加的炎症反应会使学习和记忆表现恶化，减少区域脑血流量（rCBF），增加白细胞浸润和海马神经元细胞死亡。实验验证了老年小鼠全脑缺血后炎症反应增强导致磷酸CREB和CREB水平降低的特定假设。通过证明与WT小鼠相比，IP KO小鼠的学习和记忆能力下降，海马细胞死亡增加，初步数据证实了这一假设。我们提出了四个具体的目的来验证这些假设：1)确定PGI2 （IP）受体的基因缺失是否会加重C57Bl6老年小鼠（12-15月龄）的神经行为缺陷和神经元细胞死亡，而年轻小鼠（2-3月龄）的基因缺失是否会加重C57Bl6老年小鼠（12-15月龄）的神经行为缺陷和神经元细胞死亡。2)确定与年轻小鼠和对照组相比，老年IP-/-小鼠是否会观察到绝对rCBF减弱和白细胞浸润增加。3)确定脑缺血后，脑缺血受体激动剂是否改善WT小鼠的学习和记忆能力，而拮抗剂是否降低学习和记忆能力。4)通过免疫组化检测神经元细胞死亡情况，并通过观察全脑缺血后1h、3h、1、4、7d不同时间点磷酸-CREB和CREB水平，探讨其作用机制。这些新型临床相关药物的开发可能为治疗全脑缺血和其他潜在的神经退行性疾病提供新的治疗策略。该研究计划将通过开发治疗性PGI2 （IP）受体刺激药物来改善老年人的学习和记忆，并控制心脏骤停引起的脑损伤，具有直接的临床前重要性。

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.