人参皂苷Rb1对大鼠局灶性脑缺血再灌注损伤后脑梗死体积及脑组织和血清IL-1β的影响

Effect of Ginsenoside Rb1 on Cerebral Infarction Volume and IL-1β in the Brain Tissue and Sera of Focal Cerebral Ischemia/Reperfusion Injury Model Rats

目的研究人参皂苷Rb1对大鼠局灶性脑缺血再灌注损伤(ischemia-reperfusion injury,I/R)后脑梗死体积及脑组织和血清中炎症因子IL-1β的影响。方法采用线栓法建立大鼠I/R模型,将SD大鼠随机分为假手术组,模型组,人参皂苷Rb1低(20 mg/kg)、中(40 mg/kg)、高剂量(80 mg/kg)组,每组12只。假手术组大鼠仅做大脑中动脉栓塞手术,但不插入线栓。除假手术组外,另4组均接受线栓法制备大脑中动脉闭塞(middle cerebral artery occlusion,MCAO)模型,2 h后恢复大脑中动脉再灌注;人参皂苷Rb1各剂量组于脑缺血即刻腹腔注射,模型组给予等量生理盐水。观察各组大鼠脑缺血2 h再灌注损伤后24 h大鼠神经缺损程度评分、脑梗死体积、脑组织及血清IL-1β蛋白表达。结果与假手术组比较,模型组神经功能缺损程度评分提高(P<0.01),脑组织IL-1β阳性细胞数增加,血清IL-1β含量升高(P<0.05)。与模型组比较,人参皂苷Rb1中、高剂量组神经缺损程度评分降低(P<0.05,P<0.01),人参皂苷Rb1各剂量组梗死体积均缩小,脑组织IL-1β阳性细胞数减少,血清IL-1β含量降低(P<0.01,P<0.05)。与人参皂苷Rb1低剂量组比较,高剂量组神经功能缺损程度评分降低,梗死体积缩小,血清IL-1β含量升高(P<0.01,P<0.05)。结论人参皂苷Rb1(20、40、80 mg/kg)可能通过下调IL-1β的表达有效缓解大鼠局灶性脑I/R。

Objective To investigate the effect of ginsenoside Rbl on cerebral infarction volume as well as IL-1β in the brain tissue and sera of focal cerebral ischemia/reperfusion （I/R） injury model rats. Methods The I/R rat model was established by using thread according to Zea-Longa. SD rats were randomly divided into five groups, i.e., the sham-operation group, the model group, the low dose ginsenoside Rbl （20 mg/kg） group, the medium dose ginsenoside Rbl group （40 mg/kg）, and the high dose ginsenoside Rbl group （80 mg/kg）, 12 in each group. Rats in the sham-operation group only received middle cerebral artery occlusion （MCAO） but without thread insertion. The MCAO model was prepared in the rest 4 groups, followed by MCAO 2 h later. Ginsenoside Rbl at each dose was peritoneally administrated to rats in corresponding groups immediately after cerebral ischemia. Equal volume of normal saline was administered to rats in the sham-operation group. Rats＇ cerebral infarction volume, integrals of neurologic defect degree, expression of IL-1β content in the brain tissue and sera were observed 24 h after 2-h cerebral I/R. Results In the model group, integrals of neurologic defect degree were improved （P 〈 0.01）, IL-1β positive cells in the brain tissue increased and serum IL-1β content elevated （P 〈0.05）, when compared with the sham-operation group. In comparison of the model group, integrals of neurologic defect degree were lowered in the medium dose and high dose ginsenoside Rbl groups （P 〈0.05, P 〈 0.01）. The cerebral infarction volume was all shrunken in each ginsenoside Rbl group, IL-1β positive cells in the brain tissue decreased, and IL-1β content in serum reduced （P 〈0.01, P 〈0.05）. Compared with the low dose ginsenoside Rbl group, integrals of neurologic defect degree decreased, the cerebral infarction volume shrunken, and IL-1β content in serum reduced in the high dose ginsenoside Rbl group （P 〈0.01, P 〈0.05）. Conclusion Ginsenoside Rbl （20, 40, 80 mg/kg） might effectively release local cerebral ischemia by down-regulating the IL-1β expression.