灯盏花素通过microRNA-155-5p调控NF-κB减轻感染性休克大鼠脑损伤

Breviscapine regulates NF-κB through microRNA-155-5p to reduce brain damage in rats with septic shock

目的探讨灯盏花素通过miR-155-5p调控NF-κB减轻感染性休克所致脑损伤的作用机制。方法将60只SD大鼠随机分为空白对照组、模型组、灯盏花素组、miR-155-5p antagomir NC组、miR-155-5p antagomir组、灯盏花素+miR-155-5p antagomir组,每组10只,采用尾静脉注射5 mg/kg脂多糖(LPS)的方法建立感染性休克大鼠模型,评价大鼠神经功能缺损评分;HE染色观察大鼠脑组织病理损伤;TUNEL染色观察脑皮质区神经细胞凋亡情况;酶联免疫吸附法(ELISA)检测各组大鼠脑组织中肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)、白介素-1β(IL-1β)表达水平;qRT-PCR检测各组大鼠脑组织中miR-155-5p表达水平;Western blot检测各组大鼠脑组织中NF-κB、IκB蛋白表达水平。结果灯盏花素能改善大鼠神经功能,减轻大鼠大脑皮层神经细胞损伤,减少大鼠脑组织神经细胞凋亡数量,降低大鼠脑组织TNF-α、IL-6、IL-1β表达水平,降低大鼠脑组织miR-155-5p表达水平,降低大鼠脑组织NF-κB蛋白表达水平,上调IκB蛋白表达水平;miR-155-5p antagomir可阻断灯盏花素对感染性休克大鼠的上述治疗效果。结论灯盏花素减轻感染性休克大鼠所致脑损伤的作用机制可能是通过microRNA-155-5p调控NF-κB实现的。

Objective To explore the mechanism of the regulation of NF-κB by breviscapine via miR-155-5p to reduce brain injury caused by septic shock.Methods Sixty SD rats were randomly divided into control group,model group,breviscapine group,miR-155-5p antagomir NC group,miR-155-5p antagomir group,and breviscapine+miR-155-5p antagomir group,with 10 rats in each group.A rat model of septic shock was established by injecting 5 mg/kg lipopolysaccharide(LPS)into the tail vein.The neurological deficit score of rats was evaluated.The pathological injury in brain of rats was observed by HE staining.The apoptosis of neuronal cells in cerebral cortex of rats was observed by TUNEL staining.The levels of tumor necrosis factor-α(TNF-α),interleukin-6(IL-6)and interleukin-1β(IL-1β)were detected by enzyme-linked immunosorbent assay(ELISA).The level of miR-155-5p in brain tissues of rats was detected by qRT-PCR.The expressions of NF-κB and IκB in brain tissues of rats were observed by Western blot analysis.Results Breviscapine can improve the neural function of rats,alleviate the damage of cerebral cortex nerve cells,reduce the number of apoptosis of nerve cells,reduce the levels of TNF-α,IL-6,IL-1β,miR-155-5p and NF-κB in brain tissue of rats,up-regulated expression of IκB.MiR-155-5p antagomir can block the above therapeutic effect of breviscapine on septic shock rats.Conclusion The mechanism of attenuating brain injury induced by breviscapine in septic shock rats may be related to the regulation of NF-κB through microRNA-155-5p.