涤痰汤及其拆方对阿尔茨海默病大鼠行为及tau蛋白磷酸化的影响

Effects of Ditan Decoction and its splited prescription on behavior and tau phosphorylation of Alzheimer’s disease rats

目的:观察涤痰汤及其拆方组对阿尔茨海默病(AD)模型大鼠的治疗效果,并探讨其作用机制。方法:通过对SD大鼠海马注射β-淀粉样蛋白_(1-42)(Aβ_(1-42))复制AD大鼠模型,用涤痰汤全方组和各拆方煎剂灌胃,4周后利用Morris水迷宫、Western Blot检测各组大鼠空间学习记忆能力和tau蛋白磷酸化的变化。结果:与模型组比较,涤痰汤全方组和各拆方组均能减轻模型大鼠的空间学习记忆障(P<0.01,P<0.05)。涤痰汤全方组、拆方三组(人参、茯苓、甘草配伍)、拆方四组(枳实、竹茹配伍)能显著降低模型鼠tau蛋白pT205、pT231、pS396、pS404位点的磷酸化水平(P<0.01,P<0.05),拆方一组(半夏、姜南星配伍)、拆方二组(橘红、石菖蒲配伍)能显著降低tau蛋白pT231位点的磷酸化水平(P<0.01)。涤痰汤全方组、拆方三组、拆方四组能显著降低磷酸酯酶2A(PP2A)蛋白催化亚基pY307位点的磷酸化从而上调其活性(P<0.01,P<0.05);涤痰汤全方组及各拆方组都能明显增加糖原合成酶激酶-3β(GSK-3β)蛋白pS9位点的磷酸化从而抑制其活性(P<0.01)。结论:涤痰汤全方组和拆方组能激活PP2A、抑制GSK-3β,减轻tau蛋白的过度磷酸化,改善模型大鼠的空间学习记忆障碍。

Objective:To observe the therapeutic effects of Ditan Decoction and its decomposed recipes on Alzheimer’s disease(AD)rats,and to explore its mechanism.Methods:The model of AD rats was established by injecting Aβ1-42 into bilateral hippocampus of SD rats.The rats were administrated with Ditan Decoction group and each splited prescription.Morris water maze and Western Blot were used to detect the changes of the spatial learning and memory ability and phosphorylation of tau protein in each group after 4 weeks.Results:Compared with the model group,Ditan Decoction group and each splited prescription group could alleviate the spatial learning and memory impairment of model rats(P<0.01,P<0.05).Ditan Decoction group,splited prescription three group(GinsengRadix et Rhizoma,Poria,GlycyrrhizaeRadix et Rhizoma),splited prescription four group(Aurantii Fructus Immaturus,Bambusae Caulis InTaenias)could significantly reduce the phosphorylation levelof tau protein pT205,pT231,pS396,pS404 locus in model rats(P<0.01,P<0.05);splited prescription one group(Pinellia Rhizoma,Arisaematis Rhizoma Preparatum),splited prescription two group(Citri Grandis Exocarpium,Acori Tatarinowii Rhizoma)could significantly reduce the phosphorylation level of tau protein pT231 locus(P<0.01).Ditan Decoction group,splited prescription three groups and splited prescription four groups could significantly reduce the phosphorylation of pY307 site of PP2Ac protein and increase its activity(P<0.01,P<0.05);Ditan Decoction group and each splited prescription group could significantly increase the phosphorylation of pS9 site of GSK3βprotein and inhibit its activity(P<0.01).Conclusion:Ditan Decoction and the splited prescription group can activate PP2A and inhibit GSK3β,alleviate the hyperphosphorylation of tau protein and improve the spatial learning and memory impairment in model rats.