The Department of Anesthesiology and Operation Room, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China; Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.
Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.
Int Immunopharmacol. 2023 Jul;120:110292. doi: 10.1016/j.intimp.2023.110292. Epub 2023 May 12.
NLR family pyrin domain-containing 3 (NLRP3)-mediated pyroptosis plays a key role in various acute and chronic inflammatory diseases. Targeted inhibition of NLRP3-mediated pyroptosis may be a potential therapeutic strategy for various inflammatory diseases. Ergolide (ERG) is a sesquiterpene lactone natural product derived from the traditional Chinese medicinal herb, Inula britannica. ERG has been shown to have anti-inflammatory and anti-cancer activities, but the target is remains unknown.
HYPOTHESIS/PURPOSE: This study performed an in-depth investigation of the anti-inflammatory mechanism of ERG in NLRP3-mediated pyroptosis and NLPR3 inflammasome related sepsis and acute lung injury model.
ELISA and Western blot were used to determine the IL-1β and P20 levels. Co-immunoprecipitation assays were used to detect the interaction between proteins. Drug affinity response target stability (DARTS) assays were used to explore the potential target of ERG. C57BL/6J mice were intraperitoneally injected with E. coli DH5α (2 × 10 CFU/mouse) to establish a sepsis model. Acute lung injury was induced by intratracheal administrationof lipopolysaccharide in wild-type mice and NLRP3 knockout mice with or without ERG treatment.
We showed that ERG is an efficient inhibitor of NLRP3-mediated pyroptosis in the first and second signals of NLRP3 inflammasome activation. Furthermore, we demonstrated that ERG irreversibly bound to the NACHT domain of NLRP3 to prevent the assembly and activation of the NLRP3 inflammasome. ERG remarkably improved the survival rate of wild-type septic mice. In lipopolysaccharide-induced acute lung injury model, ERG alleviated acute lung injury of wild-type mice but not NLRP3 knockout mice.
Our results revealed that the anti-pyroptosis effect of ERG are dependent on NLRP3 and NLRP3 NACHT domain is ERG's direct target. Therefore, ERG can serve as a precursor drug for the development of novel NLRP3 inhibitors to treat NLRP3 inflammasome mediated inflammatory diseases.
NLR 家族富含吡咯域蛋白 3（NLRP3）介导的细胞焦亡在各种急、慢性炎症性疾病中发挥关键作用。靶向抑制 NLRP3 介导的细胞焦亡可能是治疗各种炎症性疾病的潜在策略。埃格尔德（ERG）是一种倍半萜内酯天然产物，来源于传统中药旋覆花。研究表明，ERG 具有抗炎和抗癌活性，但靶点尚不清楚。
假说/目的：本研究深入探讨了 ERG 在 NLRP3 介导的细胞焦亡和 NLPR3 炎性体相关脓毒症和急性肺损伤模型中的抗炎机制。
采用 ELISA 和 Western blot 检测 IL-1β和 P20 水平。采用免疫共沉淀实验检测蛋白相互作用。采用药物亲和反应靶标稳定性（DARTS）实验探索 ERG 的潜在靶点。采用腹腔注射 E. coli DH5α（2×10 CFU/只）建立脓毒症模型。采用气管内滴注脂多糖诱导野生型和 NLRP3 敲除型小鼠急性肺损伤模型，并给予 ERG 处理。
我们发现，ERG 是 NLRP3 炎性体激活的第一和第二信号中 NLRP3 介导的细胞焦亡的有效抑制剂。此外，我们证明 ERG 不可逆地结合 NLRP3 的 NACHT 结构域，从而阻止 NLRP3 炎性体的组装和激活。ERG 显著提高了野生型脓毒症小鼠的生存率。在脂多糖诱导的急性肺损伤模型中，ERG 缓解了野生型小鼠的急性肺损伤，但对 NLRP3 敲除型小鼠没有作用。
我们的结果表明，ERG 的抗细胞焦亡作用依赖于 NLRP3，且 NLRP3 NACHT 结构域是 ERG 的直接靶点。因此，ERG 可作为新型 NLRP3 抑制剂的前药，用于治疗 NLRP3 炎性体介导的炎症性疾病。
