Neuroprotective Mechanisms of Neuroglobin in Stroke

脑红蛋白（Ngb）是最近发现的一种组织球蛋白，在脑组织中表达，对氧具有高亲和力。 脊椎动物的大脑初步观察表明，Ngb对缺氧缺血损伤具有神经保护作用。 然而，潜在的神经保护机制仍有待确定。我们提出3个目标， 研究在缺氧/缺血条件下，升高的Ngb改善 线粒体呼吸，减少ROS和RNS的形成，抑制细胞死亡信号，并减少 谷氨酸释放过程调节生存。 在目标1中，我们将研究Ngb在调节线粒体功能和氧化应激中的作用。 介导的神经元死亡后氧-葡萄糖剥夺和缺氧损伤体外。的生物标志物 线粒体完整性、ROS和NO/ RNS产生、细胞死亡信号传导和细胞毒性将被 考察将Ngb过表达神经元中的反应与对照（野生型）小鼠进行比较。 皮质神经元，特别注意Ngb转基因神经元中的基线水平。 目的二：研究脑红蛋白对脑缺血的保护作用。关于Ngb 在小鼠短暂（2小时）局灶性脑缺血后通过蛋白质印迹检测表达， 免疫组化和RT-PCR。线粒体ATP水平、ROS和RNS产生、细胞死亡 将检测信号传导、谷氨酸释放。所有基线测量和卒中后变化将 在Ngb过表达转基因小鼠与野生型同窝出生小鼠中进行比较。 在目的3中，我们将研究脑梗死后Ngb在神经功能结局和功能恢复中的作用， 体内缺血。急性局灶性卒中后1-6小时，临床相关的能量应激替代标志物 将通过MR成像进行分析。在第3天，形态学结局包括梗死、水肿和BBS 将测量泄漏。将使用一组标准测试来评估神经恢复。 Ngb过表达转基因小鼠的基线和终点变化将与 在永久性和短暂性2小时局灶性脑缺血后匹配野生型同窝仔。 这些拟议的实验应该为Ngb如何保护神经元免受 缺氧/缺血，并可能最终导致新的治疗策略，急性治疗中风。

Neuroglobin (Ngb) is a recently discovered tissue globin with a high affinity for oxygen expressed in the vertebrate brain. Initial observations suggest that Ngb is neuroprotective against hypoxic-ischemicinsults. However, the underlying neuroprotective mechanisms remain to be defined. We propose 3 aims to investigate the overall hypothesis that under hypoxia/ischemia conditions, elevated Ngb improves mitochondria respiration, reduces ROS and RNS formation, inhibits cell death signaling, and diminishes glutamate release processes that modulate survival. In Aim 1, we will examine the role of Ngb in regulating mitochondria function and oxidative stress- mediated neuronal death after oxygen-glucose deprivation and hypoxic insults in vitro. Biomarkers of mitochondria integrity, ROS, and NO/ RNS production, cell death signaling, and cytotoxicity will be examined. Responses in Ngb over-expressing neurons will be compared with control (wild-type) mouse cortical neurons, with special attention to baseline levels in the Ngb transgenic neurons. In Aim 2, we will assess neuroprotective effects of Ngb in cerebral ischemia in vivo. Profiles of Ngb expression will be examined after transient (2 hrs) focal cerebral ischemia in mice by western blot, immunohistochemistry and RT-PCR. Mitochondria ATP levels, ROS and RNS production, cell death signaling, glutamate release will be examined. All measurements of baselines and changes after stroke will be compared in Ngb over-expressing transgenic mice versus wild-type littermates. In Aim 3, we will investigate roles of Ngb in neurological outcome and functional recovery after cerebral ischemia in vivo. After acute focal stroke for 1-6 hrs, clinically relevant surrogate markers of energetic stress will be analyzed by MR imaging. At 3 days, morphological outcomes including infarction, edema and BBS leakage will be measured. A standard battery of tests will be used to assess neurological recovery. Baselines and changes of endpoints for Ngb over-expressing transgenic mice will be compared against matching wild-type littermates after permanent and transient 2 hr focal cerebral ischemia. These proposed experiments should provide new insight into how Ngb protects neurons from hypoxia/ischemia and may ultimately lead to novel therapeutic strategies for the acute treatment of stroke.