NLRP3炎性小体介导的细胞焦亡在芥子气所致皮肤炎性损伤中的作用及机制研究

Mustard gas (SM) is one of the major chemical terrorism in the world and the main agent of jacws in China, a serious threat to health and safety. SM often cause skin erosion and difficult healing. Inflammation plays an key role in SM induced skin injury. Recently, it was found that NLRP3 inflammasome induced pyroptosis plays a key role in inflammatory skin injury induced by external stimuli and SIRT3-SOD-mtROS signaling pathway is closely related to the regulation of NLRP3 inflammasome formation. Our previous studies showed that SM inhibited the expression of SIRT3 and promoted the expression of NLRP3 inflammasome and pyroptosis related proteins. So we propose the hypothesis:“SM actives NLRP3 inflammasome through activation of the SIRT3-SOD-mtROS signaling pathway. NLRP3 inflammasome induces pyroptosis. Inflammatory factors released by pyroptosis cause excessive inflammation. Excessive inflammation causes the skin refractory wounds.” This project will combine the keratinocytes, hairless mice, SIRT3-/- mice and other research models to explore the relationship between the effect of SM on NLRP3 inflammasome and its mediated pyroptosis and inflammatory skin damage mediated refractory wounds through interfering with gene expression and signaling pathways, and make clear the role of SIRT3-SOD-mtROS signaling pathway in the process. We hope to elucidate the mechanism of SM induced skin inflammation injury and provide new strategy and theoretical basis for promoting the healing of SM damaged skin.

芥子气（SM）是主要的全球化学恐怖之一和我国日遗化武，严重威胁着健康和安全。SM常引起皮肤糜烂难愈性损伤，炎症反应在其中起关键作用。新近研究发现，NLRP3炎性小体介导的细胞焦亡在外界刺激引起的皮肤炎性损伤中起关键作用，而SIRT3-SOD-mtROS信号通路与调控炎性小体形成关系密切。我们前期实验证实SM抑制SIRT3表达，促进NLRP3炎性小体和细胞焦亡相关蛋白表达，据此提出“SM通过SIRT3-SOD-mtROS信号通路激活NLRP3炎性小体，诱导细胞焦亡；释放出的炎性因子引起过度炎症，导致皮肤难愈”的假说。本项目将结合角质形成细胞、无毛小鼠、SIRT3-/-小鼠等研究模型，干预基因表达，探讨NLRP3炎性小体及其介导的细胞焦亡与SM皮肤炎性难愈损伤的关系，并明确SIRT3-SOD-mtROS信号通路在其中的作用，以期阐明SM引起皮肤炎症损伤机制，为SM皮肤损伤的防治提供新的策略。

糜烂性毒剂常引起皮肤和呼吸道糜烂难愈性损伤，炎症反应在其中起关键作用，但其具体机制不清。氮芥（NM）和芥子气（SM）同为糜烂性毒剂，其毒性机制相似。维生素D3 (VD3)具有良好的抗炎性能，被认为是治疗糜烂性毒剂诱导的毒性损伤的潜在候选药物；但其潜在机制目前尚不清楚。在本研究中，我们通过体内外实验发现NM通过抑制 SIRT3-SOD2-mtROS信号通路，激活 NLRP3炎性小体，促进 Caspase1活化，增加 IL-1β的表达和分泌，从而诱导角质形成细胞炎性损伤。VD3通过抑制NLRP3炎症小体，改善了NM诱导的皮肤炎症，而NLRP3炎症小体部分通过SIRT3-SOD2-mtROS信号通路介导。这些结果为VD3治疗NM诱导的皮肤毒性提供了一种新的分子机制。此外，我们通过人支气管上皮细胞16HBE细胞实验发现NM通过抑制VDR/Nrf2/SIRT3-SOD2-mtROS轴引起细胞活力下降，细胞凋亡增加。VD3通过激活VDR，促进Nrf2核内表达，激活SIRT3-SOD2-mtROS信号通路，从而保护支气管上皮细胞。本研究结果为糜烂性毒剂的炎性损伤机制提供了新线索，为VD3用于糜烂性毒剂的防治提供了新的实验依据。