Confilin的N-Hcy修饰在蛛网膜下腔出血脑损伤中的作用机制研究

Hcy是引发加剧蛛网膜下腔出血（SAH）的独立风险因子，但其相关机制未明。文献显示：N-Hcy修饰引发相关蛋白功能改变是Hcy毒性的重要机制；Cofilin去磷酸化水平决定了Cofilin rod形成和神经细胞凋亡，是SAH关键干预靶点。预实验结果显示：①Hcy处理可显著增加神经细胞损伤和Cofilin去磷酸化；②Cofilin第60、164和170位赖氨酸可显著被Hcy修饰。据此假设：Cofilin的N-Hcy修饰可导致Cofilin去磷酸化，促进Cofilin rod形成和细胞凋亡，从而引发加剧SAH脑损伤。为证此假设，本项目拟通过质谱分析、Co-IP等技术分析Hcy对SAH脑损伤、Cofilin功能等影响；明确Cofilin的N-Hcy修饰作用位点和该修饰对SAH脑损伤的影响，揭示Hcy引发加剧蛛网膜下腔出血损伤相关机制，为研发理想药物治疗Hcy-SAH相关脑出血疾病提供新思路。

Homocystein (Hcy) is an established risk factor for exacerbating subarachnoid hemorrhage (SAH), but the related mechanisms remain unknown. Literature reports that N-Hcy modification triggers changes in related protein functions, which can be an important mechanism of Hcy toxicity. Cofilin dephosphorylation level determines cofilin rod formation and neuronal apoptosis, which is a key target for SAH intervention. The applicant's preliminary demonstrate that: ① Hcy treatment significantly increases neuron damage and cofilin dephosphorylation; ② Cofilin lysine at positions 60, 164 and 170 can be significantly modified by Hcy. Based on this evidence, we hypothesize that: cofilin's N-Hcy modification can facilitate dephosphorylation of cofilin, promote the formation of Cofilin rods and apoptosis, and trigger the exacerbation of SAH damage of brain. To test this hypothesis, we propose to investigate the effects of Hcy on SAH cerebral injury and cofilin function through mass spectrometry and Co-IP. We will further clarify the N-Hcy modification site of cofilin and the effects of this modification on SAH damage, and explore the mechanisms by which Hcy aggravate subarachnoid hemorrhage injury. Our study will shed light on the development of potential drugs to treat Hcy-SAH-related cerebral hemorrhage diseases.