RKIP结合ASC的激活通过小鼠脑出血后的半胱天冬酶-1/GSDMD信号通路减轻神经元焦亡和脑损伤。
Activation of RKIP Binding ASC Attenuates Neuronal Pyroptosis and Brain Injury via Caspase-1/GSDMD Signaling Pathway After Intracerebral Hemorrhage in Mice.
作者信息
Gu Lingui, Sun Mingjiang, Li Ruihao, Tao Yihao, Luo Xu, Xu Jing, Wu Xuan, Xie Zongyi
机构信息
Department of Neurosurgery, The Second Affiliated Hospital, Chongqing Medical University, 76 Linjiang Road, Chongqing, 400010, China.
Center for Stem Cell and Regenerative Medicine, Zhejiang University School of Medicine, Hangzhou, 310058, China.
出版信息
Transl Stroke Res. 2022 Dec;13(6):1037-1054. doi: 10.1007/s12975-022-01009-4. Epub 2022 Mar 31.
Pyroptosis has been proven to be responsible for secondary brain injury after intracerebral hemorrhage (ICH). A recent study reported that Raf kinase inhibitor protein (RKIP) inhibited assembly and activation of inflammasome in macrophages. Our present study aimed to investigate the effects of RKIP on inflammasome-mediated neuronal pyroptosis and underlying neuroprotective mechanisms in experimental ICH. Here, we showed that RKIP expression was decreased both in cerebrospinal fluid (CSF) samples from patients with ICH and in the peri-hematoma tissues after experimental ICH. In mouse ICH model, activation of RKIP remarkably improved neurological deficits, reduced brain water content and BBB disruption, and promoted hematoma absorption at 24 h after ICH, as well as alleviated neuronal degeneration, reduced membrane pore formation, and downregulated pyroptotic molecules NLRP3, caspase-1 P20, GSDMD-N, and mature IL-1β. Besides, RKIP activation decreased the number of caspase-1 P20-positive neurons after ICH. However, RKIP inhibitor reserved the neuroprotective effects of RKIP at 24 h following ICH. Moreover, RKIP could bind with ASC, then interrupt the assembly of NLRP3 inflammasome. Mechanistically, inhibiting the caspase-1 by VX-765 attenuated brain injury and suppressed neuronal pyroptosis after RKIP inhibitor-pretreated ICH. In conclusion, our findings indicated that activation of RKIP could attenuate neuronal pyroptosis and brain injury after ICH, to some extent, through ASC/Caspase-1/GSDMD pathway. Thus, RKIP may be a potential target to attenuate brain injury via its anti-pyroptosis effect after ICH.
细胞焦亡已被证明与脑出血(ICH)后的继发性脑损伤有关。最近的一项研究报道,Raf激酶抑制蛋白(RKIP)可抑制巨噬细胞中炎性小体的组装和激活。我们目前的研究旨在探讨RKIP对实验性ICH中炎性小体介导的神经元焦亡的影响及其潜在的神经保护机制。在此,我们发现ICH患者脑脊液(CSF)样本和实验性ICH后血肿周围组织中RKIP表达均降低。在小鼠ICH模型中,激活RKIP可显著改善神经功能缺损,降低脑含水量和血脑屏障破坏,促进ICH后24小时血肿吸收,减轻神经元变性,减少膜孔形成,并下调焦亡分子NLRP3、半胱天冬酶-1 P20、GSDMD-N和成熟的IL-1β。此外,RKIP激活可减少ICH后半胱天冬酶-1 P20阳性神经元的数量。然而,RKIP抑制剂在ICH后24小时保留了RKIP的神经保护作用。此外,RKIP可与ASC结合,进而中断NLRP3炎性小体的组装。机制上,用VX-765抑制半胱天冬酶-1可减轻RKIP抑制剂预处理的ICH后的脑损伤并抑制神经元焦亡。总之,我们的研究结果表明,激活RKIP可在一定程度上通过ASC/半胱天冬酶-1/GSDMD途径减轻ICH后的神经元焦亡和脑损伤。因此,RKIP可能是通过其在ICH后抗焦亡作用减轻脑损伤的潜在靶点。