自噬流紊乱诱导mtDNA氧化损伤在氧化石墨烯致中枢神经焦亡的调控机制

氧化石墨烯(GO)在神经医学的广泛应用使其生物风险剧增。研究表明GO暴露可诱发中枢神经功能损伤。申请人前期研究亦发现，GO能诱导自噬流紊乱引发神经细胞程序性死亡，然而，凋亡抑制剂不能完全逆转神经毒性。细胞焦亡作为一种新型的促炎程序性死亡，与中枢神经病变密切相关。那么，GO能否通过诱导自噬流紊乱导致神经细胞焦亡？调控靶点位于何处？针对上述问题，国内外鲜见报道。预实验发现，GO阻碍自噬流进程导致线粒体氧化应激，mtDNA氧化损伤并释放至细胞浆，神经细胞出现NLRP3激活等焦亡反应。恢复自噬流可缓解mtDNA损伤，进而下调NLRP3的表达。因此提出科学假说：GO诱导自噬流紊乱引发mtDNA氧化损伤及释放，最终导致神经细胞NLRP3依赖性焦亡。本课题拟构建GO暴露体内外模型，利用基因沉默、免疫共沉淀等技术，揭示自噬流-mtDNA-焦亡轴在GO神经毒性中的调控机制，为其在临床安全应用提供防治靶点。

GO has significant advantages in the field of neuromedicine, but there also exists safety risks. Current studies have shown that GO exposure can induce functional damage of the central nervous. The applicant's previous studies also found that GO can induce programmed cell death through autophagy flow disorder. However, apoptosis inhibitors do not completely reverse neurotoxicity. As a new type of proinflammatory programmed death, pyroptosis has been found to be closely related to pathological changes of the central nervous. So, can GO cause pyroptosis of nerve cells by inducing autophagy flow disorder? Where are the regulatory targets between them? These problems are rarely reported at home and abroad. Preliminary experiments of the applicant showed that GO blocked the process of autophagy flow, leading to mitochondrial oxidative stress. Furthermore, damage mtDNA was caused and released into the cytoplasm, leading to NLRP3 activation and other pyroptosis responses. The restoration of autophagy process can alleviate the oxidative damage of mtDNA and further down-regulate the expression of NLRP3. Therefore, the scientific hypothesis is proposed: GO-induced autophagy flow disorder leads to oxidative damage and release of mtDNA, which then results in NLRP3 dependent pyrolysis of nerve cells. This project intends to construct an in vivo and in vitro model of GO exposure, and reveal the regulatory mechanism of autophagy flow-mtDNA-pyroptosis axis in GO neurotoxicity by means of gene silencing, immunoprecipitation and other technologies, so as to provide prevention targets for safe applications of GO in biomedical field.