褐藻多糖硫酸酯对大鼠脑缺血再灌注损伤后的神经保护作用

目的探讨褐藻多糖硫酸酯（FPS）对脑缺血再灌注损伤的神经保护作用及可能机制。方法将48只大鼠按照随机数字表法分为假手术组、大脑中动脉栓塞（MCAO）组、FPS低剂量组（MCAO＋FPS 50 mg/kg）、FPS高剂量组（MCAO＋FPS 100 mg/kg）,每组12只。假手术组大鼠只分离右侧颈总动脉及颈内外动脉,MCAO组、FPS低剂量组、FPS高剂量组采用线栓法制作大脑中动脉栓塞模型,缺血2 h后再灌注后FPS低、高剂量组予鼠尾静脉注射FPS50、100 mg/kg。对所有大鼠按照Longa标准进行神经功能评分;采用TTC法测量脑梗死体积;蛋白印迹法测定Nrf2蛋白的表达。结果与MCAO组比较,FPS低、高剂量组大鼠神经功能评分明显降低、转录因子NF-E2相关因子2（NF-E2-related factor 2,Nrf2）蛋白表达明显增高,FPS高剂量组神经功能评分、Nrf2蛋白表达改变得更为显著（P〈0.05,P〈0.01）;FPS高剂量组大鼠脑梗死体积明显减小（P〈0.01）。结论 FPS通过提高Nrf2的表达缩小脑梗死体积,对脑缺血再灌注损伤大鼠起到神经保护作用。

Neuroprotective Effect of Fucoidan in Rats after Cerebral Ischemia-reperfusion Injury

Objective To investigate the neuroprotective effect and possible mechanisms of Fucoidan（ FPS） in rats after cerebral ischemia-reperfusion injury. Methods A total of 48 rats were divided into sham group（ n = 12）,middle cerebral artery occlusion（ MCAO group,n = 12）,low dose of FPS group（ MCAO ＋ FPS50 mg / kg） and high dose of FPS group（ MCAO ＋ FPS 100 mg / kg,n = 12） according to random digits table method. The right common carotid artery and external carotid artery in rats of sham operation group were separated. In the cerebral ischemia-reperfusion injury group,low dose and high dose of FPS groups,middle cerebral artery occlusion models were made by suture method,and then FPS level dropped after reperfusion was given after ischemia for 2 h,and the FPS was injected via caudal veins with50 and 100 mg / kg respectively in high dose of FPS group. All rats underwent nerve function evaluation by the Longa score of nerve behavior,the volume of cerebral infarction by TTC（ triphenyl tetrazolium chloride） method and the Nrf2 expression by Western blotting. Results Compared with those in the MCAO group,the nerve function scores in low dose and high dose of FPS groups were significantly reduced,and the Nrf2 expression levels were significantly increased. In high dose of FPS group,the changes of score and Nrf2 expression were more significant（ P 〈0. 05,P〈0. 01）; while the volume of cerebral infarction was significantly reduced（ P〈0. 01）. Conclusion FPS may protect nerves by raising the Nrf2 expression to reduce the volume of cerebral infarction in rats after cerebral ischemia-reperfusion injury.