银杏内酯B对恢复期缺血性脑中风小鼠神经功能及脑组织炎症的影响

Effects of Ginkgolide B on Neurological Function and Inflammation of Brain Tissue in Convalescent Mice withIschemic Stroke

目的:探讨银杏内酯B对恢复期缺血性脑中风小鼠神经功能及脑组织炎症的影响,并分析其作用机制。方法:选取50只C57BL/6实验小鼠为实验对象,将其随机分为假手术组、空白对照组、短程给药组、长程给药组以及长程给药+拮抗剂组。除假手术组给予假手术外,其余4组小鼠均进行小鼠大脑中动脉闭塞模型制备。术后,空白对照组不给予药物干预,短程给药组术后连续1周腹腔注射银杏内酯B,长程给药组术后连续2周腹腔注射银杏内酯B,长程给药+拮抗剂组术后连续2周腹腔注射银杏内酯B,且术后第8~14d的银杏内酯B给药前3h,给予腹腔注射p38MAPK选择性拮抗剂PD169316。分别采用错步实验、水迷宫实验测定5组小鼠的运动平衡功能和神经功能,采用ELISA法测定小鼠脑组织匀浆中的炎性因子水平。结果:(1)错步实验。重复测量方差分析结果显示,时间点的主效应显著(F=138.238,P<0.01),时间点与分组间的交互作用显著(F=3.695,P<0.01),组别的主效应显著(F=303.238,P<0.01),事后LSD检验结果显示,其余4组小鼠错步率均高于假手术组,短程给药组、长程给药组、长程给药+拮抗剂组小鼠错步率均低于空白对照组。(2)水迷宫实验:5组小鼠穿过平台次数、目标象限时间比及目标象限路程比较,差异均有统计学意义(F值分别为21.221、15.650和25.148,P值均<0.05),且其余4组小鼠各指标值均低于假手术组,短程给药组、长程给药组、长程给药+拮抗剂组小鼠各指标值均高于空白对照组。(3)炎症反应:5组小鼠脑组织匀浆中TNF-α、IL-1β、IL-18表达水平比较,差异有统计学意义(F值分别为388.001、226.849和124.816,P值均<0.05),且其余4组小鼠各炎性因子的表达水平均高于假手术组,短程给药组、长程给药组、长程给药+拮抗剂组小鼠各炎性因子的表达水平均低于空白对照组。结论:银杏内酯B有利于改善小鼠MCAO后运动平衡功能及神经功能、缓解炎症反应,且恢复期继续给予银杏内酯B有利于进一步促进其功能恢复,推测其作用机制可能与调控p38MAPK信号通路激活相关。

OBJECTIVE To investigate the effects of Ginkgolide B(GB)on neurological function and brain inflammation in mice with ischemic stroke in recovery period,and analyze its mechanism.METHODS 50 C57BL/6 experimental mice were randomly divid⁃ed into five groups:the Sham surgery group(sham group),the blank control group(GB0w group),the short-term administration group(GB1w group),the long-term administration group(GB2w group),and the long-term administration+antagonist group(GB2w+PD169316 group).In addition to the Sham surgery group,the remaining four groups of mice were given MCAO model preparation.Af⁃ter the operation,no drug intervention was given to the GB0w group,and GB was intraperitoneally injected into the GB1w group one week before the operation.The GB2w group received intraperitoneal injection of GB in the first 2 weeks after surgery,while the GB2w+PD169316 group received intraperitoneal injection of GB in the first 2 weeks after surgery.On days 8~14,p38MAPK selec⁃tive antagonist PD169316 was administered intraperitoneally 3 hours before GB administration.The motor balance function and neu⁃ral function of 5 groups of mice were measured using the staggered step experiment and water maze experiment,respectively.The levels of inflammatory factors in the mouse brain tissue homogenate were measured using ELISA method.RESULTS(1)There was a statistically significant difference in the misclassification rate among the 5 groups of mice at 1 day,7 days,14 days,21 days,and 28 days after intervention,the differences were statistically significant(F=410.169,473.731,381.060,235.712,313.748,P<0.05).More⁃over,the misstep rate of the other four groups was higher than that of Sham group,and the misstep rate of GB1w group,GB2w group and GB2w+PD169316 group was lower than that of GB0w group.(2)Water maze experiment:there were statistically significant differ⁃ences in the number of times mice crossed the platform,target quadrant time ratio,and target quadrant distance ratio among the five groups of mice(F=21.221,15.650,25.148,P<0.05).Moreover,the index values of the other four groups were lower than those of Sham group,and the index values of GB1w,GB2w and GB2w+PD169316 groups were higher than those of GB0W group.(3)Inflam⁃matory response:there was a statistically significant difference in TNF-α,IL-1β,IL-18 levels in the brain tissue homogenate of five groups of mice(F=388.001,226.849,124.816,P<0.05).Moreover,the expression levels of each inflammatory factor in the other four groups were higher than that in Sham group,and the expression levels of mice in GB1w,GB2w and GB2w+PD169316 groups were lower than those in GB0w group.CONCLUSION GB is beneficial for improving motor balance and neurological function,allevi⁃ating inflammatory response in mice after MCAO,and continued administration of GB during the recovery period is beneficial for fur⁃ther promoting functional recovery.It is speculated that p38MAPK signaling pathway activation may be involved into this mechanism.