金思维提取物对APPV717I转基因小鼠海马神经元PP2A表达的影响

【作者】 杨益昌；

【导师】 田金洲；

【作者基本信息】 北京中医药大学 ， 中西医结合临床， 2011， 硕士

【摘要】 目的：研究金思维提取物(GEPT)对APPV717I转基因小鼠海马神经元蛋白磷酸酶2A(PP2A)表达的影响。方法：将3月龄的APPV717I转基因小鼠60只随机分为模型组、多奈哌齐组(0.92mg/kg/d)、GEPT小剂量组(0.075g/kg/d)、GEPT中剂量组(0.15g/kg/d)和GEPT大剂量组(0.3g/kg/d),并以同月龄遗传背景相同的C57BL/6J小鼠12只作为正常对照组,治疗组每天灌胃给药1次,正常组及模型组给予0.5%羧甲基纤维素钠溶液灌胃。给药8个月后(11月龄)用免疫组化法和免疫蛋白质印迹法测定海马神经元PP2A的表达水平结果：免疫组化染色结果显示模型组小鼠海马神经元CA1区PP2A染色较淡,阳性细胞数和阳性细胞总面积较正常组明显减少(P<0.01)；GEPT小、中、大剂量组小鼠海马神经元CA1区PP2A阳性细胞数和阳性细胞总面积与模型组比较明显增加(P<0.01):GEPT小剂量组小鼠海马神经元CAl区PP2A阳性细胞数和阳性细胞总面积与正常组比较有显著性差异(P<0.05,P<0.01)；GEPT中、大剂量组小鼠海马神经元CA1区PP2A阳性细胞数和阳性细胞总面积与正常组比较无显著性差异(P>0.05),疗效接近多奈哌齐组。免疫蛋白质印迹结果显示模型组小鼠海马神经元PP2A表达与正常组比较明显减少(P<0.01)；GEPT小、中、大剂量组小鼠海马神经元PP2A表达与模型组比较明显增加(P<0.01)；GEPT小剂量组小鼠海马神经元PP2A表达与正常组比较有显著性差异(P<0.05)；GEPT中、大剂量组小鼠海马神经元PP2A表达与正常组比较无显著性差异(P>0.05),疗效接近多奈哌齐组。该结果和免疫组化结果相一致。结论：GEPT可增加APPV717I转基因小鼠海马神经元PP2A的表达,提示GEPT可能通过此途径减轻APPV717I转基因小鼠海马神经元tau蛋白的异常过度磷酸化。更多还原

【Abstract】 Objective:To investigate the effect of GEPT extract on expression of protein phosphatase 2A (PP2A) in hippocampal neurons of APPV717I transgenic mice.Methods:60 three-month-old APPV717I transgenic mice were randomly divided into model group, donepezil group (0.92mg/kg/d), GEPT low-dose group (0.075g/kg/d), GEPT medium-dose group(0.075g/kg/d) and GEPT high-dose group (0.075g/kg/d), and 12 three-month-old C57BL/6J mice of the same genetic background were set as normal control group, the treatment groups were administered oral ly 1 time a day, and both the control group and model group were given 0.5% sodium carboxymethylcellulose (CMC) solution. Immunohistochemistry and Western blot analysis were used to detect the expression of protein phosphatase 2A (PP2A) in hippocampal neurons of APPV717I transgenic mice after 8 months drug administration (11 months old).Results:Immunohistochemical staining of PP2A in hippocampal CA1 region neurons of the model group were thin, and the number of positive cells and the total area of positive cells were significantly decreased compared with that of the control group (P<0.01); the number of pos i t ive cells and the total area of positive cells of the GEPT low, medium and high-dose group were significantly increased compared with that of the model group (P<0.01); the number of positive cells and the total area of positive cells of the GEPT low-dose group showed significant difference compared with that of the control group (P<0.05, P<0.01); the number of positive cells and the total area of positive cells of the GEPT medium and high-dose group showed no significant difference compared with that of the control group (P>0.05), and the effectiveness were similar compared with that of the donepezil group.Western blot analysis of PP2A expression in hippocampal neurons of the model group were significantly decreased compared with that of the control group (P<0.01); the PP2A expression of the GEPT low, medium and high-dose group were significantly increased compared with that of the model group (P<0.01); the PP2A expression of the GEPT low-dose group showed significant difference compared with that of the control group (P<0.05); the PP2A expression of the GEPT medium and high-dose group showed no significant difference compared with that of the control group (P>0.05), and the effectiveness were similar compared with that of the donepezil group. The results of Western blot analysis were similar to that of Immunohistochemistry.Conclusion:GEPT can activate the expression of PP2A in hippocampal neurons of APPV717I transgenic mice, which prompt GEPT may attenuate abnormal hyperphosphorylation of tau protein in hippocampal neurons of APPV717I transgenic mice through this way.更多还原