Department of Neurology, Shandong Provincial ENT Hospital, Shandong Provincial ENT Hospital affiliated to Shandong University, 250022, China.
Department of Internal Medicine, 316thHospital of PLA, Beijing 100091, China.
Biomed Pharmacother. 2019 Sep;117:109155. doi: 10.1016/j.biopha.2019.109155. Epub 2019 Jul 1.
Stroke is a leading cause of mortality and disability globally. Cerebral ischaemia-reperfusion (I/R) injury is characterized by significant inflammation and extensive cell death. Multiple signaling pathways play essential roles in the process, and identifying the unclear crucial regulators of these pathways may provide promising targets for treatment. CASP8 and FADD-like apoptosis regulator (CFLAR) is expressed in multiple organs to regulate inflammation. Here, we reported that CFLAR expression was markedly reduced in brain samples of mice with middle cerebral artery occlusion (MCAO) stroke. Furthermore, CFLAR knockdown markedly elevated the neurological deficit, brain water content and the infarct volume. In addition, significantly promoted inflammation and endoplasmic reticulum (ER) stress was detected in brain tissues of mice after MCAO, as evidenced by the promoted expression of p-IκBα, p-nuclear factor (NF)-κB (p65), glucose-regulated protein 78 (GRP78), PKR-like ER kinase (PERK), activating transcription factor-6 (ATF-6) and cleaved Caspase-12. Notably, MCAO-induced cerebral I/R injury was markedly alleviated in mice over-expressing CFLAR through suppressing inflammation and ER stress. Furthermore, our in vitro results indicated that oxygen-glucose deprivation (OGD)-induced cell death was evidently ameliorated by CFLAR over-expression. In contrast, the cell death triggered by OGD was accelerated by CFLAR knockdown in vitro through enhancing Caspase-3 cleavage, and this effect was obviously ameliorated by the blockage of ER stress using 4-phenyl butyric acid (4-PBA). Collectively, these results demonstrated that CFLAR could be considered as a novel candidate to develop effective therapeutic treatment against cerebral I/R injury.
中风是全球范围内导致死亡和残疾的主要原因。脑缺血再灌注(I/R)损伤的特征是炎症显著和广泛的细胞死亡。多个信号通路在该过程中发挥着重要作用,确定这些通路中不清楚的关键调节因子可能为治疗提供有希望的靶点。CASP8 和 FADD 样凋亡调节剂(CFLAR)在多个器官中表达,以调节炎症。在这里,我们报道 CFLAR 在大脑中动脉闭塞(MCAO)中风小鼠的脑样本中表达明显减少。此外,CFLAR 敲低明显增加了神经功能缺损、脑含水量和梗死体积。此外,在 MCAO 后,小鼠脑组织中检测到炎症和内质网(ER)应激显著增加,证据是 p-IκBα、p-核因子(NF)-κB(p65)、葡萄糖调节蛋白 78(GRP78)、PKR 样内质网激酶(PERK)、激活转录因子-6(ATF-6)和切割 Caspase-12 的表达增加。值得注意的是,通过抑制炎症和 ER 应激,过表达 CFLAR 明显减轻了 MCAO 诱导的脑 I/R 损伤。此外,我们的体外结果表明,过表达 CFLAR 明显改善了氧葡萄糖剥夺(OGD)诱导的细胞死亡。相比之下,通过增强 Caspase-3 切割,CFLAR 敲低在体外加速了 OGD 引发的细胞死亡,而使用 4-苯丁酸(4-PBA)阻断 ER 应激明显改善了这种作用。总之,这些结果表明 CFLAR 可以被认为是开发针对脑 I/R 损伤的有效治疗方法的新候选药物。