黑素瘤2型(AIM2)炎症小体的缺失通过诱导细胞焦亡和炎症反应而导致缺血性脑损伤。我们的研究小组先前已经证明,ATP敏感性钾通道(KATP通道)开放剂可以调节缺血性卒中后神经元突触可塑性以进行神经保护。然而,KATP通道在缺血性卒中后炎症反应中的具体机制尚不清楚.这里,我们通过观察BV-2形态和活力的变化来评估细胞损伤。TTC染色,mNSS评分,尼氏染色,和TUNEL染色用于评估行为缺陷,脑损伤严重程度,和大脑中动脉阻塞(MCAO)小鼠的神经元损伤。实时荧光定量PCR(RT-qPCR)评估氧糖剥夺/再灌注(OGD/R)后AIM2的表达,而西方印迹,免疫荧光,酶联免疫吸附试验(ELISA)检测焦亡相关蛋白的表达,核因子-κB/κBα抑制剂(NF-κB/IκBα)信号激活,和急性缺血期的炎性细胞因子分泌。我们观察到OGD/R后NF-κB核易位和NF-κB/IκBα炎症途径的激活增加。此外,AIM2蛋白表达上调并定位在BV-2细胞的细胞质内。值得注意的是,低剂量尼可地尔治疗降低了焦亡相关蛋白的表达,包括AIM2,切割的半胱氨酰天冬氨酸特异性蛋白酶-1(切割的半胱天冬酶-1),GasderminD全长(GSDMD-FL),和GasderminDN端(GSDMD-NT),降低BV-2细胞的成孔破裂率。进一步的研究表明,KATP通道抑制剂5-HD上调了p-NF-κBp65,NF-κBp65和p-IκBα的表达,促进小胶质细胞活化,焦亡,和炎症因子分泌,在体内减弱尼可地尔的神经保护作用。总的来说,我们的研究结果表明,开放KATP通道可以通过抑制AIM2炎症小体诱导的小胶质细胞焦亡和NF-κB/IκBα信号激活来改善缺血后神经功能.
The absent in melanoma 2 (AIM2) inflammasome contributes to ischemic brain injury by inducing cell pyroptosis and inflammatory responses. Our research group has previously demonstrated that ATP-sensitive potassium channels (KATP channels) openers can modulate neuronal synaptic plasticity post-ischemic stroke for neuroprotection. However, the specific mechanisms of KATP channels in the inflammatory response following ischemic stroke remain unclear. Here, we assessed cellular damage by observing changes in BV-2 morphology and viability. 2,3,5-Triphenyl tetrazolium chloride (TTC) staining, mNSS scoring, Nissl staining, and TdT-mediated dUTP nick end labeling (TUNEL) staining were used to evaluate behavioral deficits, brain injury severity, and neuronal damage in mice subjected to middle cerebral artery occlusion (MCAO). Quantitative real-time polymerase chain reaction (qRT-PCR), Western blotting, immunofluorescence, and enzyme-linked immunosorbent assay (ELISA) were used to measure cell pyroptosis and nuclear factor-kappaB (NF-κB) activation in vivo and in vitro. We observed that AIM2 protein expression was upregulated and localized within the cytoplasm of BV-2 cells. Notably, low-dose Nicorandil treatment reduced inflammatory cytokine secretion and pyroptosis-related protein expression, including AIM2, cleaved cysteinyl aspartate-specific protease-1 (cleaved caspase-1), and Gasdermin D N-terminal (GSDMD-NT). Further investigations revealed that the KATP channel inhibitor 5-HD upregulated p-NF-κB p65, NF-κB p65, and p-IκBα expression, reversing Nicorandil\'s neuroprotective effect in vivo. In summary, our results suggest that Nicorandil may serve as a potential therapeutic option for ischemic stroke. Targeting AIM2 and NF-κB represents effective strategies for inhibiting neuroinflammation.