电针内关、百会通过NLRP3/ASC/Caspase-1通路干预局灶性脑缺血再灌注损伤大鼠的作用研究

Effect of electroacupuncture at Neiguang("PC6")and Baihui("DU20")on focal cerebral ischemia-reperfusion injury through NLRP3/ASC/Caspase-1 pathway in rats

目的通过NOD样受体热蛋白结构域相关蛋白3(NOD-like receptor thermal protein domain associated protein 3,NLRP3)/凋亡相关斑点样蛋白(apoptosis-associated speck-like protein containing CARD,ASC)/半胱天冬酶-1(Caspase-1)通路探讨电针内关、百会对局灶性脑缺血再灌注损伤大鼠的干预作用及机制。方法Sprague-Dawley大鼠30只,随机分为对照组、假手术组、模型组、尼莫地平组、电针组,每组6只。模型组、尼莫地平组、电针组予以大脑中动脉栓塞(middle cerebral artery occlusion,MCAO)造模,成功后尼莫地平组予10.8 mg/kg尼莫地平片灌胃,电针组予以针刺内关、百会,对照组、假手术组均给予0.9%生理盐水灌胃,干预14 d。采用Longa评分进行神经功能评定,采用ELISA法检测血清白介素-1β(interleukin-1 beta,IL-1β)含量,免疫荧光测定NLRP3、ASC、Caspase-1阳性表达。结果造模后,模型组、尼莫地平组、电针组Longa评分明显升高,与对照组、假手术组相比,差异有统计学意义(P<0.05);干预后,尼莫地平组、电针组Longa评分低于模型组(P<0.05),而尼莫地平组、电针组之间的Longa评分差异无统计学意义(P>0.05)。干预后,模型组大鼠IL-1β含量高于对照组、假手术组(P<0.01);尼莫地平组、电针组大鼠IL-1β含量低于模型组(P<0.05)。干预后,模型组ASC、Caspase-1及NLRP3的表达明显高于对照组、假手术组(P<0.01);与模型组比较,尼莫地平组、电针组ASC、Caspase-1及NLRP3的表达明显降低(P<0.01)。结论电针内关、百会可改善局灶性脑缺血再灌注损伤大鼠运动功能,可能与调控NLRP3/ASC/Caspase-1信号通路、降低IL-1β表达有关。

Objective To investigate the effect and mechanism of electroacupuncture at Neiguan("PC6")and Baihui("DU20")on focal cerebral ischemia-reperfusion injury in rats through NOD-like receptor thermal protein domain associated protein 3,(NLRP3)/apoptosis-associated speck-like protein containing CARD(ASC)/Caspase-1 pathway.Methods Thirty Sprague-Dawley rats were randomly divided into control group,sham operation group,model group,nimodipine group and electroacupuncture group,with 6 rats in each group.Middle cerebral artery occlusion(MCAO)was performed in the model group,nimodipine group,and electroacupuncture group.After success,the nimodipine group was given nimodipine 10.8 mg/kg intragastric administration,while electroacupuncture group was given Neiguan("PC6")and Baihui("DU20")acupuncture,the control group and the sham operation group were given 0.9%normal saline by gavage for 14 d.Longa score was used to evaluate neurological function.The level of interleukin-1 beta(IL-1β)in serum was measured by ELISA and the expression of NLRP3,ASC,Caspase-1 was detected by immunofluorescence.Results After modeling,Longa scores of model group,nimodipine group and electroacupuncture group were significantly higher than those of control group and sham operation group(P<0.05),after intervention,Longa score in nimodipine group and electroacupuncture group was lower than that in model group(P<0.05),but there was no significant difference in Longa score between nimodipine group and electroacupuncture group.After intervention,the content of IL-1βin model group was higher than that in control group and sham operation group(P<0.01),and the content of IL-1βin nimodipine group and electroacupuncture group was lower than that in model group(P<0.05).After intervention,the expression of ASC,Caspase-1 and NLRP3 in model group was significantly higher than that in control group and sham operation group(P<0.01).Compared with model group,the expression of ASC,Caspase-1 and NLRP3 in nimodipine group,electroacupuncture group was significantly lower(P<0.01).Conclusion Electroacupuncture at Neiguan("PC6")and Baihui("DU20")can improve the motor function of rats with focal cerebral ischemia-reperfusion injury,which may be related to regulating the NLRP3/ASC/Caspase-1 signaling pathway and decreasing the expression of IL-1β.