Abstract
Objective To investigate the neuroprotective effect of lycium barbarum polysaccharide (LBP) on cerebral ischemia-reperfusion injury in mice and its mechanism.Methods ICR mice were randomly divided into 7 groups according to body weight,12 cases in each group,The experimental group of low,middle and high dose (gavaged LBP 10,20 and 40 mg kg-1),control group (gavaged nimodipine 4 mg · kg-1);while the normal group,sham operation group and model group were given 0.9％ NaCl 10 mL · kg-1,1 time/day.Seven days after continuously gavaged,the modified Longa method was used to establish the middle cerebral artery occlusion model.The neurological function of mice with cerebral ischemia and reperfusion after 24 h was evaluated.The volume of cerebral infarction,neuronal apoptosis in ischemic hippocampus of mice was detected.The expression of B-cell lymphoma-2 gene (Bcl-2) and B-lymphoma-2 gene-related X protein (Bax) in brain tissue in each group was detected by Western blot.Results The cerebral infarct volume (％) of model group,control group and experimental -L,-M,-H groups were 36.64 ± 2.48,13.26 ± 0.29,28.49 ± 0.87,22.15 ± 0.69,17.45 ± 0.56,which were significantly higher than the normal group and sham operation group (P ＜ 0.01).The apoptosis rate (AR,％) of model group,control group and experimental-L,-M,-H groups were 78.15 ± 2.65,32.16 ± 2.05,65.48 ± 0.95,40.13 ± 1.21,35.16 ± 1.05,which were significantly higher than the normal group and sham operation group (P ＜ 0.01).The cerebral infarction volume and AR in the control group,the experimental-L,-M,-H groups were lower than those in the model group (P ＜ 0.01).The relative expression of Bax protein in sham operation group,model group,control group and experimental-M were 0.02 ± 0.01,0.32,± 0.01,0.22 ± 0.01,0.25 ± 0.01 respectively.The relative expression of Bcl-2 were 34.51 ± 0.01,0.24 ± 0.01,0.37 ± 0.02,0.38 ± 0.01 respectively,compared with the sham group,the relative expression of Bcl-2 in model group decreased,and the relative expression of Bax increased (P ＜ 0.05 or P ＜ 0.01);compared with the model group,the expression of Bcl-2 increased and the expression of Bax decreased in the control group and the experimental-M group (P ＜ 0.05 or P ＜0.01).Conclusion LBP inhibits the expression of pro-apoptotic protein Bax after cerebral ischemia-reperfusion injury,promotes the expression of anti-apoptotic Bcl-2,inhibits cell apoptosis and plays an important role in anti-apoptotic cells neuroprotective effects.关键词
枸杞多糖/脑缺血再灌注损伤/神经保护/B细胞淋巴瘤-2/B淋巴细胞瘤-2基因相关X蛋白Key words
lycium barbarum polysaccharides/cerebral ischemia-reperfusion injury/neuroprotection/B-cell lymphoma-2/B-lymphoma-2 gene-related X protein分类
医药卫生
