Electrophilic Warhead-Based Design of Compounds Preventing NLRP3 Inflammasome-Dependent Pyroptosis

Pyroptosis is a caspase-1-dependent pro-inflammatory form of programmed cell death implicated in the pathogenesis of autoinflammatory diseases as well as in disorders characterized by excessive cell death and inflammation. Activation of NLRP3 inflammasome is a key event in the pyroptotic cascade. In this study, we describe the synthesis and chemical tuning of α,β-unsaturated electrophilic warheads toward the development of antipyroptotic compounds. Their pharmacological evaluation and structure–activity relationships are also described. Compound 9 was selected as a model of this series, and it proved to be a reactive Michael acceptor, irreversibly trapping thiol nucleophiles, which prevented both ATP- and nigericin-triggered pyroptosis of human THP-1 cells in a time- and concentration-dependent manner. Moreover, 9 and other structurally related compounds, inhibited caspase-1 and NLRP3 ATPase activities. Our findings can contribute to the development of covalent, multitarget antipyroptotic compounds targeting molecular components of the NLRP3 inflammasome regulatory pathway.细胞焦亡（Pyroptosis）是一种依赖半胱天冬氨酸蛋白酶-1（caspase-1）的促炎型程序性细胞死亡，其参与自身炎症性疾病的发病机制，也与以过度细胞死亡和炎症为特征的疾病相关。NLRP3炎性小体（NLRP3 inflammasome）的激活是焦亡级联反应中的关键事件。本研究报道了α,β-不饱和亲电弹头的合成与化学修饰，以开发抗焦亡化合物，并阐述了其药理学评价与构效关系。研究选取化合物9作为该系列的模型分子，经证实其为具有反应活性的迈克尔受体，可不可逆地捕获巯基亲核试剂，并以时间和浓度依赖的方式，抑制ATP及尼日利亚菌素诱导的人THP-1细胞焦亡。此外，化合物9及其他结构相关化合物可抑制半胱天冬氨酸蛋白酶-1与NLRP3的ATP酶活性。本研究结果可为靶向NLRP3炎性小体调控通路分子组分的共价、多靶点抗焦亡化合物的开发提供参考依据。