Effects of Electroacupuncture on Learning-memory and P35/P25-Cyclin-dependent Kinase 5-Tau Phosphorylation Signal Pathway in Prefrontal Cortex of Rats with Alzheimer's Disease / 中国康复理论与实践

ABSTRACT

Objective:To observe the effect of electroacupuncture at Baihui (DU20) and Shenshu (BL23) acupoints on learning-memory ability and expression of the relative protein of P35/P25-cyclin-dependent kinase 5 (CDK5)-Tau phosphorylation signaling pathway in the prefrontal cortex (PFC) in rats with Alzheimer's disease (AD), so as to reveal its potential mechanisms in treating AD. Methods:Male adult Sprague-Dawley rats were randomly divided into normal control group, sham group, model group and treatment group with six rats in each group. The AD model was constructed by bilateral hippocampal injection of Aβ25-35 in latter two groups. Equal amount of normal saline was injected into the sham group. The treatment group was acupunctured at Baihui and Shenshu once a day for ten days. All the rats were tested with Morris Water Maze. Immunohistochemistry staining and Western blotting were used to detect the related protein of P35/P25-CDK5-Tau protein phosphorylation in the PFC. Results:Compared with the normal control group and the sham group, the escape latency and escape length increased (P < 0.05) and the times crossing the platform reduced (P < 0.05) in the model group; compared with the model group, the escape latency and escape length reduced (P < 0.05), and the times crossing the platform increased (P < 0.05) in the treatment group. The optical density of P35/P25 and CDK5 were significantly higher in the model group than in the normal control group and the sham group (P < 0.01), and they were lower in the treatment group than in the model group (P < 0.001). The relative expression of P35/P25, CDK5, Tau[pS199] and Tau[pS202] were higher in the model group than in the normal control group and the sham group (P < 0.05), and the expression of the above proteins was lower in the treatment group than in the model group (P < 0.05). Conclusion:Electroacupuncture could improve the learning-memory and spatial exploration ability, which associate with inhabiting the P35/P25-CDK5-Tau protein phosphorylation signaling pathway in the PFC to delay the development of AD.