胡黄连苷Ⅱ对脑缺血再灌注损伤大鼠血脑屏障的保护作用机制探讨  

Protective effect of Picroside Ⅱ on blood-brain barrier in rats with cerebral ischemia-reperfusion injury and its mechanism

作　　者：刘敏[1] 翟丽[1] 张睿[2] 王婷婷[2] 张红艳[2] 郭云良[2] 

机构地区：[1]青岛市市立医院药剂科,青岛266003 [2]青岛大学附属医院脑血管病研究所

出　　处：《中华生物医学工程杂志》2017年第3期177-182,共6页Chinese Journal of Biomedical Engineering

基　　金：国家自然科学基金（81274116）

摘　　要：目的 探索胡黄连苷Ⅱ对大鼠脑缺血再灌注（I/R）后血脑屏障（BBB）的保护作用和机制.方法 将150只Wistar大鼠随机分为5组（剔除死亡）,假手术组、模型组、胡黄连苷Ⅱ治疗组、夹竹桃麻素阳性对照药物组、胡黄连苷Ⅱ与夹竹桃麻素共同作用组,每组25只大鼠.应用栓线法建立大鼠大脑中动脉栓塞（MCAO）模型,腹腔注射胡黄连苷Ⅱ干预治疗.大鼠脑缺血2 h再灌注22 h后,ELISA检测脑组织活性氧（ROS）的含量,TTC染色测量梗死体积,依文思蓝法检测BBB的通透性,硝酸镧透射电镜观察BBB的结构,Western blotting检测ROCK、MLCK、MMP-2、Claudin-5的表达水平.结果 大鼠造模后,脑组织ROS含量增高,皮质区梗死明显,BBB的通透性增加、结构受损,大鼠脑组织ROCK、MLCK、MMP-2蛋白表达明显增强,Claudin-5表达明显减弱;胡黄连苷Ⅱ治疗后,大鼠脑组织梗死体积明显缩小（14.12％±1.73％比34.75％±4.32％,P〈0.01）,BBB渗漏率和镧颗粒漏出显著减少,ROS含量明显降低（P〈0.05）.ROCK、MLCK、MMP-2蛋白表达下降（P〈0.05）,Claudin-5表达明显增强（P〈0.05）.结论 胡黄连苷Ⅱ可能通过下调ROCK、MLCK、MMP-2表达,上调Claudin-5表达,从而减轻BBB损伤,发挥神经保护作用.Objective To investigate the protective effect of Picroside Ⅱ on blood-brain barrier （BBB）in rats with cerebral ischemia-reperfusion（I/R）and its mechanism. Methods A total of 150 Wistar rats were randomly divided into 5 groups （excluding death）,the sham operation group,model group, Picroside Ⅱ treatment group,Acetovanillon positive control group,and Picroside Ⅱ and Acetovanillon group （n=25 each）. The model of middle cerebral artery occlusion （MCAO） was established by suture-occluded method. Intraperitoneal injection of PicrosideⅡ was performed for intervention. The rats were subjected to cerebral ischemia for 2 h and reperfusion for 22 h. ELISA was used to determine the content of reactive oxygen species（ROS）in the brain tissues. TTC staining was used to measure the infarct volume. The permeability of BBB was determined by Evans Blue method. The structure of BBB was examined by lanthanum nitrate transmission electron microscopy. Western blotting was used to determine the expression levels of ROCK,MLCK,MMP-2 and Claudin-5. Results After the rat model was established,the content of ROS in brain tissue increased,the infarction at the cortical area was obvious,the BBB permeability increased whereas the structure was damage,the protein expression of ROCK,MLCK and MMP-2 in the brain tissues significantly increased,and the Claudin-5 expression significantly decreased. After the treatment with PicrosideⅡ,the infarct volume of the brain tissue significantly reduced（14.12%± 1.73%vs 34.75%±4.32%,P〈0.01）;the BBB percolation rate and lanthanum particles leakage significantly reduced;and the ROS content significantly decreased（P〈0.05）. The protein expression of ROCK,MLCK and MMP-2 decreased （P〈0.05）,and the expression of Claudin-5 significantly increased （P〈0.05）. Conclusion Picroside Ⅱ may down-regulate the expression of ROCK,MLCK and MMP-2,up-regulate the expression of Claudin-5,as to reduce the damage of BBB with a neuroprotective effect.

关 键 词：脑缺血 再灌注损伤 血脑屏障 胡黄连苷Ⅱ 

分 类 号：R285.5[医药卫生—中药学]