螺旋藻多糖对阿尔茨海默病模型小鼠脑线粒体氧化应激保护

摘要

Objective To study the protective effect of spirulina polysaccharide against cerebral mitochondrial oxidative stress induced by D-galactose and sodium nitrite in Alzheimer's disease (AD) mice model. Methods A total of 40 mice were randomly divided into the normal group (C), model group (M), and other three experimental groups (spirulina polysaccharide, El group of 6.7 mg·kg-1·d-1, Em group of 67.0 mg·kg-1·d-1, and Eh group of 134.0 mg·kg-1·d-1, 8 weeks), with 8 mice in each group. The model group and three experimental groups were injected with D-galactose 120 mg/kg and sodium nitrite 100 mg/kg for AD model. Morris water maze (MWM) experiment and Biochemical index test were per-formed after 8 weeks. Results Compared with group M, the number of crossed platform in 120 s and target exploration time in Em group and Eh group were significantly increased (P<0.05);While the Aβ1~42 content in brain were decreased with the order:M>El>Em>C>Eh. Compared with group M, the activity of manganese superoxide dismutase (MnSOD) were improved with the order:C [(64.22±22.31) Um/mg]>Eh [(58.36±21.30) Um/mg]>Em [(56.58±15.66) Um/mg]>E1 [(55.32±21.25) Um/mg]>M [(42.68±11.58) Um/mg]. The activities of reactive oxygen species (ROS) in Eh group [30.70±4.68 mmol/L] and Malondialdehyde (MDA) in Em group [(35.55±7.97) nmol/mg] and Eh group [(30.51±8.74) nmol/mg] were significantly decreased (P<0.05). Compared with El group, Eh group had the best protective effect against oxida-tive stress. Conclusion Spirulina polysaccharide can protect AD model mice from the damage of cerebral mitochondri-al oxidative stress, which is the nutrients of cerebral mitochondria, and high dose of spirulina polysaccharide has the best protective effect.%目的：探索螺旋藻多糖对D-半乳糖联合亚硝酸钠诱导的阿尔茨海默病(AD)模型小鼠脑线粒体损伤的抗氧化保护作用。方法小鼠腹腔注射D-半乳糖120 mg/kg和亚硝酸钠100 mg/kg制备AD模型。将40只小鼠按数字编号随机分为正常组(C组)、模型组(M组)以及3个剂量实验组，每组8只，3个剂量实验组分别给予螺旋藻多糖灌胃低剂量(El组)6.7 mg·kg-1·d-1，中剂量(Em组)67.0 mg·kg-1·d-1，高剂量(Eh组)134.0 mg·kg-1·d-1，连续8周，在给药第8周后，进行Morris水迷宫实验和生化指标测试。结果与M组相比，Em组、Eh组120 S内跨越平台的次数和在目标象限的探索时间均明显增加(P<0.05)；小鼠脑部β淀粉样蛋白(Aβ1~42)含量减少，依次是M组>El组>Em组>C组>Eh组。氧化应激指标：与M组相比，锰超氧化物歧化酶（Mn-SOD）活性均有提高(P<0.05)，依次是C组(64.22±22.31) Um/mg>Eh组(58.36±21.30) Um/mg>Em组(56.58±15.66) Um/mg>E1组(55.32±21.25) Um/mg>M组(42.68±11.58) Um/mg；活性氧(NOS)含量Eh组(30.70±4.68) mmol/L显著下降(P<0.05)，丙二醛(MDA)活性Em、Eh组[(35.55±7.97) nmol/mg、(30.51±8.74) nmol/mg]显著下降；与E1组相比，Eh组抗氧化效果最好。结论螺旋藻多糖对阿尔茨海默病模型小鼠脑线粒体氧化应激有保护作用，是脑线粒体营养素，高剂量效果最佳。