NLRP3 inflammasome-mediated microglial pyroptosis is critically involved in the development of post-cardiac arrest brain injury
NLRP3 inflammasome-mediated microglial pyroptosis is critically involved in the development of post-cardiac arrest brain injury
复制标题
NLRP3炎症小体介导的小胶质细胞焦亡与心脏骤停后脑损伤的发生密切相关
DOI：
10.1186/s12974-020-01879-1
复制
发表时间：
2020-07-23
影响因子：
9.3
通讯作者：
Huang, Kaibin
中科院分区：
文献类型：
--
作者：
Chang, Yuan;Zhu, Juan;Huang, Kaibin
背景：脑损伤是心脏骤停幸存者死亡和残疾的主要原因，人们认为神经炎症在其中起着关键作用，但潜在机制仍不明确。细胞焦亡是一种促炎性程序性细胞死亡形式，在受到感染或其他刺激时会引发炎症反应。本研究旨在了解小胶质细胞焦亡在心脏骤停后脑损伤中的作用。
方法：对雄性Sprague-Dawley大鼠进行10分钟窒息性心脏骤停及心肺复苏或假手术。采用流式细胞术分析、蛋白质免疫印迹法、实时荧光定量聚合酶链反应（qRT-PCR）、免疫共沉淀和免疫荧光法，评估心脏骤停后活化的小胶质细胞和CD11b阳性白细胞，并检测特定细胞群体的炎症小体激活和细胞焦亡情况。为进一步探究潜在机制，分别给予MCC950或Ac-YVAD-cmk以阻断NOD样受体家族蛋白3（NLRP3）或半胱天冬酶-1（caspase-1）。
结果：研究结果显示，在大鼠模型中，心脏骤停后成功复苏会导致小胶质细胞焦亡以及随之而来的炎症浸润，这一过程由NLRP3炎症小体的激活介导。使用选择性抑制剂MCC950和Ac-YVAD-cmk分别靶向细胞焦亡的执行者NLRP3和caspase-1，可显著抑制小胶质细胞焦亡，减少白细胞浸润，改善神经功能预后，并减轻建模大鼠心脏骤停后的神经病理损伤。
结论：本研究表明，由NLRP3炎症小体介导的小胶质细胞焦亡在心脏骤停后脑损伤的发病机制中至关重要，并提供了一种新的治疗策略。
BackgroundBrain injury is the leading cause of death and disability in survivors of cardiac arrest, where neuroinflammation is believed to play a pivotal role, but the underlying mechanism remains unclear. Pyroptosis is a pro-inflammatory form of programmed cell death that triggers inflammatory response upon infection or other stimuli. This study aims to understand the role of microglial pyroptosis in post-cardiac arrest brain injury.MethodsSprague-Dawley male rats underwent 10-min asphyxial cardiac arrest and cardiopulmonary resuscitation or sham-operation. Flow cytometry analysis, Western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), co-immunoprecipitation, and immunofluorescence were used to evaluate activated microglia and CD11b-positive leukocytes after cardiac arrest and assess inflammasome activation and pyroptosis of specific cellular populations. To further explore the underlying mechanism, MCC950 or Ac-YVAD-cmk was administered to block nod-like receptor family protein 3 (NLRP3) or caspase-1, respectively.ResultsOur results showed that, in a rat model, successful resuscitation from cardiac arrest resulted in microglial pyroptosis and consequential inflammatory infiltration which was mediated by the activation of NLRP3 inflammasome. Targeting NLRP3 and caspase-1, the executor of pyroptosis, with selective inhibitors MCC950 and Ac-YVAD-cmk treatment significantly prevented microglial pyroptosis, reduced infiltration of leukocytes, improved neurologic outcome, and alleviated neuro-pathological damages after cardiac arrest in modeling rats.ConclusionsThis study demonstrates that microglial pyroptosis mediated by NLRP3 inflammasome is critically involved in the pathogenesis of post-cardiac arrest brain injury and provides a new therapeutic strategy.