清脑抗炎汤调控miR-223/NLRP3炎症小体通路对远端大脑中动脉闭塞大鼠神经功能、炎症反应及Caspase-1/Caspase-3表达的影响OA

Objective:To investigate the neuroprotective effect of Qingnao Kangyan Decoction(QNKYD)on rats with distal middle cerebral artery occlusion(dMCAO),to clarify its anti-inflammatory regulatory mechanism through the miR-223/NLRP3 inflammasome pathway.Methods:85 male SPF-grade Sprague-Dawley(SD)rats were used.The dMCAO rat model was established by the suture-occluded method.15 rats underwent only vascu-lar exposure without occlusion as the sham operation group.The successfully modeled rats were randomly divided into dMCAO model group(n=15),QNKYD treatment group(QNKYD 150 mg/kg by gavage,n=15),QNKYD+miR-223 antagonist group(QNKYD 150 mg/kg by gavage and intracerebroventricular injection of antagomiR-223,n=15),and miR-223 antagonist control group(intracerebroventricular injection of antagomiR-223,n=15).Inter-vention started 24 h after operation.The QNKYD treatment group and QNKYD+miR-223 antagonist group re-ceived QNKYD by gavage daily.The miR-223 antagonist control group and QNKYD+miR-223 antagonist group received intracerebroventricular injection of antagomiR-223(10 nmol/10 μL)at 1 h after modeling.The sham oper-ation group and dMCAO model group were given the same volume of normal saline by gavage and intracerebroven-tricular injection.After 7 days of intervention,neurological function scores were evaluated;cerebral infarct vol-ume was detected by TTC staining;levels of inflammatory factors IL-1β and IL-18 in serum and brain tissue were measured by ELISA;miR-223 expression in brain tissue was detected by RT-qPCR;protein expressions of NL-RP3,ASC,caspase-1,and caspase-3 in brain tissue were determined by Western blotting.Results:Compared with the sham operation group,the dMCAO model group showed increased neurological function scores,enlarged cerebral infarct volume,elevated contents of IL-1β and IL-18 in serum and brain tissue,down-regulated miR-223 expression,and significantly up-regulated protein expressions of NLRP3,ASC,caspase-1,and caspase-3 in the brain(P<0.05).After intervention with QNKYD,the above indicators were significantly reversed,including im-proved neurological function,reduced infarct volume,decreased inflammatory factor levels,up-regulated miR-223 expression,and inhibited expression of NLRP3 inflammasome-related proteins(P<0.05).In the QNKYD+miR-223 antagonist group,this protective effect was significantly weakened and all indicators deteriorated again(P<0.05).There was no significant difference in all indicators between the miR-223 antagonist alone group and the dMCAO model group(P>0.05).Conclusion:Qingnao Kangyan Decoction exerts a significant neuroprotective ef-fect on dMCAO rats.Its mechanism may be related to up-regulating miR-223 expression,inhibiting the activation of NLRP3 inflammasome,and reducing the expression of caspase-1 and caspase-3,thereby alleviating inflammato-ry response and neuronal apoptosis.