颅脑创伤后铁死亡（Ferroptosis）的分子机制及治疗策略

Based on our prior research results, the model of neuron/glia mechanical injury in vitro and fluid percussion brain injury in rats will be used to observe the ferroptosis in neuron and glia, the signal transduction inside and outside neurons, iron metabolism associated proteins、the expression characteristic of ferroptosis-related genes and proteins after brain injury and treatment by Fer-1,Lip-1、many kinds of Fe-inhibitors、TFR-siRNA . The functional behavior 、neuro-radiology、histopathology and outcome of the rats will be evaluated after brain injury and different treatment.The characteristic of release-signal transduction-necroptosis regulation of different transmitters in injury area and penumbral region after injury and treatments will be emphatically compared. Our research will not only expand a comprehensive knowledge on the molecular machanism of neuron Ferroptosis initiation and activation after traumatic brain injury, but also elaborate the neuroprotection mechanism of mediated by the inhibition of Ferroptosis. Our research will also open a new area on the inversion and therapy of cell death and have a great significance on the study of drug therapy and confirmation of new therapy target in brain injury.

在前期研究工作基础上，拟应用“体外神经元/胶质细胞培养机械损伤模型”结合“大鼠液压颅脑伤模型”，动态观察细胞损伤后及Fer-1、Lip-1、多种铁抑制剂、TFR siRNA等干预下神经元与胶质细胞的Ferroptosis发生情况发生情况、细胞内外信号转导、铁代谢相关分子、Ferroptosis相关基因和蛋白表达等多个环节的不同特点；动态评估致伤动物进行各项干预措施治疗后功能行为学，神经影像学，病理组织学和预后变化，重点比较应用治疗干预后各种递质释放－信号转导－细胞Ferroptosis调控环节的异同点。本研究将阐明颅脑创伤后Ferroptosis启动和激活的分子机制，拓展对颅脑创伤后细胞死亡模式全新的认识和理解，并从源头上抑制细胞死亡启动内源性神经保护作用的机制，也为细胞死亡的逆转和治疗开创一个新的研究和应用途经，对颅脑创伤新靶点的确证以及治疗药物的研究有重要意义。

Netrin-1 (NTN1)是一种分泌性的层粘连蛋白，可以通过不同的机制参与神经系统疾病的病理生理过程。先前的研究已经证实，在创伤性脑损伤（Traumatic brain injury, TBI）后的继发性病理生理改变中，铁死亡扮演了重要的角色。铁死亡是一种近年来新发现的细胞死亡形式，与脂质过氧化密切相关。在本课题中，我们探讨了Netrin-1在TBI后神经元铁死亡中的调节作用。我们证明，Netrin-1可以通过与UNC5B受体结合激活Nrf2通路，促进GPX4转录并抑制铁死亡。在小鼠受控皮质撞击损伤模型中应用Netrin-1重组蛋白可以上调GPX4水平，减少神经元铁死亡并改善运动和认知功能，而该效应可以通过UNC5B或Nrf2的敲低抵消。