玉郎伞多糖对快速老化小鼠额叶、海马神经元丢失和Tau蛋白磷酸化的影响

Effects of Millettia pulcha Polysaccharides on Neuronal Loss and Tau Phosphorylation in Frontal Lobe and Hippocampus of SAMP8 Mice

摘要:

目的: 研究玉郎伞多糖(YLSP)对快速老化模型小鼠(SAMP8)额叶、海马神经元丢失和Tau(Ser202)异常磷酸化的影响。 方法: 选择6月龄SAMP8,随机分为模型组,石杉碱甲组(0.02 mg·kg^-1),YLSP低、高剂量组(45,180 mg·kg^-1),选择6月龄正常老化小鼠(SAMR1)作为对照组,以上各组每日上午灌胃给药l次,连续40 d,于末次给药的次日采用尼氏染色方法检测额叶和海马神经元缺失率;应用免疫组织化学方法检测额叶和海马Tau(Ser202)磷酸化水平。 结果: 模型组额叶、海马神经元缺失率分别为(46.4±8.4)%,(45.5±7.2)%。与模型组相比,石杉碱甲组(35.8±6.7)%,(34.2±5.6)%、YLSP低、高剂量组(35.1±6.4)%,(36.0±4.5)%,(25.6±6.6)%,(26.7±6.1)%额叶、海马神经元缺失率明显降低(P<0.05或P<0.01);模型组额叶、海马pSer202阳性细胞数(92.2±10.7),(98.6±11.4)个较对照组明显升高(12.3±2.1),(15.5±2.6)个(P<0.01),与模型组相比,石杉碱甲组(48.5±6.4),(56.1±3.3)个、YLSP低、高剂量组(60.7±7.5),(65.9±8.0);(50.9±5.1),(53.6±6.7)个的额叶、海马Tau(pSer202)阳性细胞数明显降低(P<0.01)。 结论: YLSP降低Tau蛋白异常磷酸化,减少脑部神经元缺失。

Abstract:

Objective: To study the effects of Millettia pulcha polysaccharides(YLSP) on neuronal loss and Tau(Ser202) phosphorylation in the frontal lobe and hippocampus of SAMP8 mouse. Method: The SAMP8 mice were adopted as AD model group, and the SAMR1 mice as the control group. Both groups were randomized and given the blank configuration solution. Huperzine(0.02 mg·kg^-1) was given to drug-positive group and two YLSP groups were given 45,180 mg·kg^-1 respectively, continuous administration for 40 days. In the frontal lobe and hippocampus, neuronal loss and Tau(Ser202) phosphorylation(pser202) were respectively detected by Nissl staining and immunohistochemical method. Result: Comparing with the normal group, the neuronal loss and the number of pSer202 positive cells of the model group were higer(P<0.01) in the frontal lobe and hippocampus. In drug-positive and YLSP groups, the neuronal loss and the number of pSer202 positive cells in the frontal lobe and hippocampus were observed obviously lower (P<0.05 or P<0.01), comparing with the model group. Conclusion: The abnormal Ser202 phosphorylation is reduced and neuronal loss of brain is ameliorated by YLSP.