YAP调控NLRP3炎性小体活化参与脓毒症休克的机制研究

Septic shock is a subset of sepsis with underlying circulatory and cellular/metabolic abnormalities. The underlying mechanism of septic shock lead to death is not very clear. The present work suggested NLRP3 inflammasome and associated pyroptosis have participated in septic shock. Our previous work found YAP, which is a transcription factor in Hippo signaling, positively regulated NLRP3 inflammasome activation by an unknown mechanism in controlling NLRP3 protein expression. Based on the initial study, we explore the role of YAP in septic shock by using YAP-conditional knockout mice to construct the mouse model and investigate the mechanism of YAP in regulating NLRP3 expression by employing molecular biology, proteomics, modification-specific proteomics, bioinformatics and other technical means. This program will perfect the theoretical system for treatment of septic shock and eventually provide new therapeutic targets for sepsis.

脓毒症休克（Septic shock）是指脓毒症合并出现严重的循环障碍和细胞代谢紊乱，目前对其致死的分子机制尚未完全阐明。现阶段研究表明NLRP3炎性小体及其下游介导的细胞焦亡与脓毒症休克密切相关。我们前期的工作发现Hippo信号通路的转录因子YAP可以正向调控NLRP3炎性小体活化，机制研究初步发现YAP参与调控NLRP3的蛋白表达，然而YAP调控NLRP3蛋白表达的具体分子机制不清楚。因此，本项目拟采用YAP巨噬细胞条件性敲除小鼠研究YAP在NLRP3炎性小体活化以及脓毒症休克中的功能，并综合运用分子生物学、蛋白组学、蛋白修饰组学、生物信息学等多种技术手段研究YAP调控NLRP3表达的分子机制，为脓毒症休克的治疗提供理论依据和新的药物靶点。

NLRP3炎性小体异常活化与脓毒症密切相关，深入研究NLRP3炎性小体调节机制可为脓毒症的致病机制以及靶向治疗提供新的方向。申请者团队研究发现Hippo信号转录因子YAP可特异性地促进NLRP3炎性小体活化，并在脓毒症发生发展中起重要促进作用。机制研究发现YAP可以转录非依赖的形式发挥功能并在蛋白水平调节NLRP3的表达：YAP通过竞争性结合NLRP3来阻断E3泛素连接酶β-TrCP1对NLRP3在K380位点的泛素化修饰，从而增强NLRP3蛋白的稳定性。相关研究结果发表在Nature Communications（2021;12(1):2674）杂志上。在该研究的启发下，我们还揭示了补体C5a-C5aR2轴促进NLRP3炎性小体活化引起脓毒症致死；发现Wnt/β-catenin信号促进NLRP3炎性小体活化参与脓毒症肺损伤；同时还鉴定了XAV939，SI-2，C646等小分子化合物可以抑制NLRP3炎性小体活化并显著改善脓毒症小鼠症状。我们围绕NLRP3炎性小体活化调控与脓毒症的系列研究为脓毒症的治疗提供了新的方向和靶点。