ABSTRACT
Objective In this study, electroacupuncture (EA) was used to analyze the expression changes of related proteins in neuroglobin (NGB), PI3K/AKT and apoptotic pathways in the temporal cortex of bilirubin encephalopathy (BE) rats, so as to investigate the therapeutic effect of EA on BE and the relevant mechanism of NGB in this process. Totally 39 seven-day-old SD rats were divided into Sham, BE model and BE+EA groups. The neonatal BE model was established by injecting bilirubin solution (10 μg UCB/g Weight) into the cerebellomedullary cistern, Sham group was injected with the same amount of normal saline. BE rats were treated with EA at Baihui (GV20) and Quchi (LI11) acupoints with the frequency of 2/15 Hz for 15 min. Treatment was performed 12 h before modeling, followed by treatment every 12 h, in a total of three times. HE, Nissl staining and electron microscopy (TEM) were used to observe the pathological and ultrastructural changes of nerve cells in each group. Results showed that EA treatment reduced the damage of cortical neurons of BE rats and increase the number of Nissl bodies. TEM confirmed that EA treatment could alleviate the degree of mitochondria edema. Immunofluorescence staining was used to detect the expression sites and cell types of NGB. Results showed that NGB was mainly expressed in cortical neurons. Western blotting showed that EA treatment increased the expression of NGB, PI3K (p110 alpha), pAKT (Ser473) (P< 0. 05, P< 0. 05 and P< 0. 01, respectively) and the ratio of apoptosis-related protein Bcl-2/Bax (P < 0. 001), decreased the expression of Cleaved Caspase-3 (P< 0. 05) in the temporal cortex of rats. TUNEL staining showed that EA reduced the number of apoptotic cells (BE group 186. 00±13. 86 vs BE+EA group 78. 67±11. 85, P< 0. 01) . This study confirms that EA can promote the expression of NGB in the temporal cortex of BE rats, then activate the PI3K/AKT pathway to exert its neuroprotective function and inhibit the occurrence of apoptosis. EA may become a potential treatment method for BE.
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.