NLRP3炎性复合体调控的基因互作通路在血管重构中的作用机制研究

NLRP3 inflammasome and downstream gene regulatory networks may affect the biological behavior of vascular cells，participate in the process of vascular remodeling and atherosclerosis (AS). Using gene expression profile analysis and cell biology experiments, we identified 23 differentially expressed genes regulated by Caspase-1, the key effector protein of NLRP3 inflammasome. Two genes (Pafah1b2 and Samd5) are associated with the progress of AS in ApoE -/- mice significantly, and Pafah1b2 may regulate the expression of Samd5. Furthermore, we identified a gene C23G5, which is also regulated by Caspase-1, is significantly associated with high-fat diet in ApoE -/- mice. The aims of the present study is to reveal the biological basis of Pafah1b2 and Samd5 in vascular remodeling and AS progression, elucidate the detailed mechanism that lead to the regulation of Pafah1b2 and Samd5 by NLRP3 inflammasome, understand the gene-gene epistatic interaction and molecular mechanism between Pafah1b2 and Samd5. Finally, to explore the role of gene-gene interaction pathway regulated by NLRP3 inflammasome in vascular remodeling and the AS, and to discover the potential diagnostic markers and intervention targets of diseases.

NLRP3炎性复合体调控的基因网络可影响构成血管微环境细胞的生物学行为，参与血管重构与动脉粥样硬化（AS）进程。应用全基因组表达谱分析和细胞生物学实验，我们筛选并确定23个受NLRP3炎性复合体效应蛋白Caspase-1调控的差异表达基因，在ApoE-/-小鼠中首先明确2个基因（Pafah1b2与Samd5）与AS进程密切相关，且Pafah1b2基因可能处于Samd5基因上游并调控其表达；初步确定1个受Caspase-1调控的基因C23G5与高脂饮食方式明显相关。本研究目标在于，明确Pafah1b2与Samd5在血管重构与AS进程中的作用与生物学基础；阐明NLRP3炎性复合体调控Pafah1b2与Samd5的详细机制，明确Pafah1b2与Samd5之间相互作用与分子机制；探讨NLRP3炎性复合体调控的基因互作通路对血管重构与AS发生发展的影响，发现潜在的疾病诊断标志物和干预靶点。

NLRP3炎性复合体调控的基因互作通路在血管重构中发挥着重要作用，Pafah1b2是该通路中关键节点之一。对NLRP3炎性复合体与Pafah1b2影响血管重构的作用机制研究结果显示NLRP3炎性复合体的效应蛋白Caspase 1通过剪切与Pafah1b2基因启动子区结合的转录因子Ap-2a影响Pafah1b2表达；Pafah1b2可影响p65表达，抑制NLRP3炎性小体组分和pro-IL-1β生成，有效减少动脉粥样硬化斑块面积、血管中膜平滑肌细胞向内膜迁移与斑块内巨噬细胞，发挥减轻局部炎症反应和延缓血管重构的作用。同时，Pafah1b2可调控NLRP3炎性复合体网络中Samd5表达并形成复杂的反馈-负反馈机制影响血管重构过程。研究中还发现miR-4660直接调控Agxt基因表达影响草酸代谢和肾结石形成，罹患肾结石增加冠心病发生风险，草酸可刺激血管壁NLRP3炎性复合体并触发血管重构；高糖通过NF-κB/miR-21/SMAD7通路促进微血管内皮-间充质转化过程与心肌纤维化，miR-21可影响Smad7通路抑制NLRP3炎性复合体活化，在草酸、高血糖等多种上游因素介导的NLRP3炎性复合体激活与血管重构中发挥作用；失眠可能通过免疫和氧化应激机制增加冠心病与消化道溃疡发生风险；MED12通过TGFβ非经典信号通路影响动脉平滑肌表型、增殖和衰老参与血管重构；导致家族性常染色体高胆固醇血症的新型突变蛋白LDLRQ722*可被sEV携带，通过肝细胞表面HSPG途径重建脂质代谢途径。上述研究结果已达预期目标，在国际期刊发表5篇学术论文，为深入研究NLRP3炎性复合体调控的基因互作通路在血管重构中的作用机制提供了基础。