大黄素通过调控Wnt/β-catenin信号通路减轻缺血性脑卒中大鼠BCFB

Emodin reduces blood-cerebrospinal fluid barrier dysfunction in cerebral arterial thrombosis rats by regulating Wnt/β-catenin signaling pathway

目的 本研究旨在探讨大黄素对缺血性脑卒中(CAT)后血-脑脊液屏障(BCFB)的影响及其潜在机制。方法 SD大鼠随机分为:假手术组、模型组、大黄素低剂量组(20 mg·kg^(-1))、大黄素高剂量组(40 mg·kg^(-1))以及阳性对照组(尼莫地平12 mg·kg^(-1))。构建大鼠大脑中动脉闭塞/再灌注(MCAO/R)模型,通过腹腔注射不同药物进行治疗。对各组大鼠进行神经功能缺损评分;TCC染色检测脑梗死体积;测定脑组织含水量;伊文思蓝(EB)染色检测BCFB通透性;明胶酶谱法评估MMP-9的活性;Western blotting检测基质金属蛋白酶-9 (MMP-9)、闭合蛋白-5 (Claudin-5)和咬合蛋白(Occludin)和磷酸化糖原合成酶激酶(p-GSK-3 β)、β-连环素(β-catenin)蛋白的表达。结果 与假手术组相比,模型组大鼠神经功能缺损评分明显增加,脑梗死体积和脑组织含水量均明显增加,脑组织EB含量明显增加,脑组织中Claudin-5、Occludin、p-GSK-3 β、β-catenin蛋白表达明显降低,MMP-9酶活性和蛋白表达明显升高(P<0.05);与模型组相比,大黄素低、高剂量组和阳性对照组大鼠神经功能缺损评分明显降低,脑梗死体积和脑组织含水量均明显降低,脑组织EB含量明显降低,脑组织中Claudin-5、Occludin、p-GSK-3 β、β-catenin蛋白表达明显升高,MMP-9酶活性和蛋白表达明显降低(P<0.05)。结论 大黄素可通过激活Wnt/β-catenin通路减轻BCFB损伤,对CAT具有神经保护作用。

Objective To explore the effect of emodin on the blood-cerebrospinal fluid barrier(BCFB)after stroke and its underlying mechanism.Methods SD rats were divided into sham operation group,model group,lowdose emodin group(20 mg·kg^(-1)),high-dose emodin group(40 mg kg^(-1)),and positive control group(nimodipine 12 mg·kg^(-1)).The rat model of middle cerebral artery thrombosis(CAT)/reperfusion(MCAO/R)was established and treated by intraperitoneal injection of different drugs.The neurological deficits were evaluated in each group.TCC staining was used to detect cerebral infarction volume.The brain tissue water content was evaluated.Evans blue(EB)staining was used to detect the permeability of the BCFB.Gelatin zymography was used to evaluate the activity of MMP-9.Western blotting was used to the detect the expression of matrix metalloproteinase-9(MMP-9),claudin-5,occluding,phosphorylation-glycogen synthase kinase 3β(p-GSK-3β)andβ-catenin protein.Results Compared with the sham operation group,the neurological dysfunction score of the rats was significantly increased,the volume of cerebral infarction and the water content of the brain tissue were significantly increased,the content of EB in the brain tissue was significantly increased,and the protein expression of Claudin-5,Occludin,p-GSK-3β,andβ-catenin in the brain tissue were significantly reduced,MMP-9 enzyme activity and protein expression were significantly increased in the model group(P<0.05).Compared with the model group,the neurological dysfunction score of the rats was significantly reduced,the volume of cerebral infarction and the water content of the brain tissue were significantly reduced,the content of EB in the brain tissue was significantly reduced,and the protein expression of Claudin-5,Occludin,p-GSK-3β,andβ-catenin in the brain tissue were significantly increased,MMP-9 enzyme activity and protein expression were significantly reduced in the emodin high and low dose groups and the positive control group(P<0.05).Conclusion Emodin can reduce BCFB by activating the Wnt/β-catenin pathway,and has a neuroprotective effect on ischemic stroke.