知母皂苷对大鼠局灶性脑缺血/再灌注损伤的保护作用

Preliminary Study on the Mechanism of Timosaponin on Cerebral Ischemia-reperfusion Injury in Rats

关键词:  知母皂苷  脑缺血再灌注  水通道蛋白4  肿瘤坏死因子α  白介素-6  白介素1β

Key words:  saponins from Anemarrhena asphodeloides Bge  cerebral ischemia and reperfusion  aquapo rin-4  TNF-α  IL-6  IL-1β

摘要:

目的 在大鼠局灶性脑缺血/再灌注损伤模型中，初步研究知母皂苷对水通道蛋白4（aquapo rin-4，AQP-4）和肿瘤坏死因子α（TNF-α）、白介素-6（IL-6）、白介素1β（IL-1β）表达的影响。方法 240只SD大鼠分为6组（40只/组）：假手术组、模型组、知母皂苷低、中、高剂量组（SA，10，20，40 mg·kg^-1）和尼莫地平组（12 mg·kg^-1）。采用"插线法"造模。再灌注48 h后，观察每组大鼠的神经症状，并进行神经行为学评分；测定脑梗死范围、脑含水量；采用伊文思蓝法对各组血脑屏障的通透性进行检测；采用酶联免疫吸附实验（ELISA）对各组TNF-α、IL-6和IL-1β的含量进行测定；采用Western blot法对各组AQP-4的含量进行测定；采用HE染色法观察各组大鼠脑组织病理形态的变化。结果 知母皂苷组能改善造模后造成的神经功能缺损、脑组织病理形态学改变；降低脑含水量、脑梗死面积和血脑屏障的通透性；下调AQP-4、TNF-α、IL-6、IL-1β的表达。结论 知母皂苷对脑缺血/再灌注SD大鼠能起到一定的保护作用，这可能是由于AQP-4和TNF-α、IL-6、IL-1β表达下调，从而维持血脑屏障的稳定性有关。

Abstract:

OBJECTIVE To investigate the effect about aquaporin-4 (AQP-4) and TNF-α, IL-6, IL-1β on cerebral ischemia-reperfusion injury in rats. METHODS Two hunderd and forty rats were divided into 6 groups (40 rats per group):sham operation group, model group, Saponins from Anemarrhena asphodeloides Bge low medium high dose group (10, 20, 40 mg·kg^-1) and nimodipine group (12 mg·kg^-1). Plug-line method was used to make focal cerebral ischemia and reperfusion of middle cerebral artery occlusion model of rats. After 48 h, the neurological score, Cerebral infarction range and brain water content was detected. The Evans blue method was used to detect the permeability of blood-brain barriers in each group. ELISA was used to detect the expression of TNF-α, IL-6, IL-1β. Western blot was used to detect the expression of AQP-4. HE strain was made to observe morphological changes of brain tissue. RESULTS Saponins from Anemarrhena asphodeloides Bge could improve the nerve damage symptoms and pathological changes of brain tissue of MCAO rat, reduce brain water content, infarct size, blood-brain barrier permeability and the expression of AQP-4, TNF-α, L-6, IL-1β. CONCLUSION Saponins from Anemarrhena asphodeloides Bge can protect cerebral ischemia-reperfusion. This effect may be regulated by reducing the expression of AQP-4 and TNF-α, L-6, IL-1β.