补阳还五汤有效部位对局灶性脑缺血再灌注后caspase表达的作用

目的 研究补阳还五汤中4类有效部位抗脑缺血再灌注损伤作用是否是通过抑制脑组织caspase表达而实现的.方法 采用大鼠大脑中动脉闭塞局灶性脑缺血模型,缺血2 h再灌注46 h,分别于缺血前和缺血后12、24、36 h给予由补阳还五汤提取的生物碱、苷、多糖和苷元,以尼莫地平为对照药.以免疫组化法检测caspase-1、caspase-3、caspase-8蛋白表达.结果 脑缺血再灌注后,缺血侧脑组织caspase-1、caspase-3蛋白表达增强,caspase-1主要表达在脉络膜,caspase-3在海马、皮质和髓质均有表达.补阳还五汤中生物碱、苷、多糖和苷元均可抑制caspase-1表达,尼莫地平对caspase-1表达无显著影响.生物碱可抑制海马和髓质区caspase-3表达,苷和苷元可抑制海马、皮质和髓质caspase-3表达,尼莫地平可抑制海马和髓质caspase-3表达,而多糖对其无显著影响.各组caspase-8表达均无显著差异.结论 补阳还五汤中生物碱、苷、多糖和苷元可能通过抑制caspase-1表达,减少炎性细胞因子的产生,从而对抗缺血后炎症反应.生物碱、苷和苷元可能通过抑制caspase-3表达,抑制缺血后神经元凋亡,从而对抗神经元迟发性死亡.生物碱、苷、多糖和苷元可能是补阳还五汤抗缺血性脑损伤的主要物质基础.

Effect of Active Fraction of Buyang Huanwu Decoction on Caspase Expression in Rats after Focal Cerebral Is-chemic Reperfusion

Objective To investigate effect of the four kinds of active fractions extracted from Buyang Huanwu Decoction ( BYHWD) on caspase expression in rats after focal cerebral ischemic reperfusion. Methods The focal cerebral ischemia/reperfusion model rats were established by middle cerebral artery occlusion for 2 hrs followed with reperfusion for 46 hrs. Before and at 12th, 24th and 36th hour after cerebral ischemia, the rats were administered with alkaloid, glycoside, polysaccharide and aglycone from BYHWD respectively , and nimodipine was given as control medicine to observe the effect of them on protein expression of caspase-1, caspase-3 and caspase-8 using immunohistochemical method. Results Protein expression of caspase-1 and caspase-3 increased in the injured lateral brain tissue after cerebral ischemia/reperfusion. Caspase-1 expression were observed mainly in choroids, while caspase-3 expression in hippocampus, cortex and medulla. All the four kinds of active fractions from BYHWD could inhibit caspase-1 expression, while nimodipine couldn't. Caspase-3 expression in hippocampus and medulla could be inhibited by alkaloid, that in hippocampus, cortex and medulla could be inhibited by glycoside and aglycone, and that in hippocampus and medulla by nimodipine, however, polysaccharide showd no effect on it. As for caspase-8 expression, no effect on it was shown in all groups. Conclusion Alkaloid, glycoside, polysaccharide and aglycone from BYHWD could relieve the inflammatory reaction occurred after cerebral ischemia/reperfusion by inhibiting caspase-1 expression to decrease production of inflammatory cytokine. Alkaloid, glycoside and aglycone could reduce neuronal apoptosis by inhibiting caspase-3 expression to antagonize the delayed neuronal death after cerebral ischemia. The 4 kinds of active fractions may be the main material basis for BYHWD in preventing ischemia/reperfusion cerebral injury.