绞股蓝对海马注射Aβ_(1-40)大鼠脑内细胞周期蛋白表达和钙稳态变化的影响

Effects of gypenosides on cell cycle-related protein expression and calcium homeostasis in hippocampal neurons of rats treated with β-amyloid protein fragmant 1-40

目的:探讨绞股蓝对海马注射Aβ1-40大鼠脑内细胞周期蛋白异常表达和钙稳态变化的影响。方法:动物随机分为绞股蓝组、模型组、对照组。运用淀粉样β蛋白双侧海马注射,模拟阿尔茨海默病脑内Aβ对神经系统的损害。Y型迷宫测试大鼠学习记忆能力,免疫组织化学染色和积分吸光度分析检测细胞周期蛋白A、B1(cyc linA、cyc lin B1),Fura-2/AM-荧光法测定海马细胞内Ca2+含量;并对绞股蓝组大鼠给予绞股蓝皂苷灌胃,观察其对AD大鼠上述各项指标变化的影响。结果:Aβ1-40海马注射大鼠学习记忆能力明显低于对照组(P<0.05),脑内细胞周期蛋白A、B1蛋白水平明显高于对照组,海马神经元内Ca2+含量显著高于对照组;而给予绞股蓝在一定程度上能改善大鼠学习记忆能力,降低cyc lin A、cyc lin B1蛋白和Ca2+含量的水平(P<0.05)。结论:绞股蓝对Aβ引起的动物学习记忆能力减退、海马神经元内异常表达细胞周期蛋白和钙稳态失衡有一定的逆转作用。

AIM ： To observe the effects of gypenosides on the expression of cell cycle - related protein and calcium homeostasis in the hippocampal neurons in the animal model of Alzheimer＇ s disease （ AD ） induced by Aβ1-40. METHODS： The animal model of AD was established through injection of Aβ1 -40 into hippocampus in rats. The ability of learning and memory were verified by the performance of Y - shape maze task. With the method of immunohistochemical staining coupled integral absorbance analysis, the expression of cell cycle related protein in hippocampus was determined in rats. The contents of cytoplasm Ca2^＋ were determined using Fura - 2/AM - fluorescence method. The effects of gypenosides on above indices were studied. RESULTS： Compared with the controls, the learning and memory ability of Aβ1-40 -injected rats were lower, the expression of cyclin A and cyclin B1 protein in rat hippocampus neurons had hoisted, the contents of calcium in hippocampus were increased significantly. Gypenosides, however, improved all the indexes in varying degrees. CONCLUSION： These results imply that gypenosides improves the learning and memory ability of the rats treated with Aβ-40, reverses the expression of cell cycle - related protein and maintains the calcium homeostasis in hippocampus neurons.