Nerve Fuyuan Recipe Mediated BDNF/TrkB Signaling Pathway To Promote Hippocampal Neuron Synaptic Plasticity In The Treatment Of Depression After Ischemic Stroke

Objective:To normatively evaluate the clinical efficacy of Shenjingfuyuan Decoction(SD)in treating post-stroke depression and its effect on serum BDNF,and to investigate the functional mechanism of Shenjingfuyuan Decoction in regulating BDNF/TrkB signal pathway to promote the synaptic plasticity of hippocampal neurons in the treatment of post-stroke depression.Methods:1.Clinical study part:120 PSD patients were divided into treatment group and control group with randomized double-blind control method.On the basis of the treatment of ischemic stroke,the treatment group was treated with Shenjingfuyuan Decoction,while the control group was treated with Chinese medicine placebo for 12 weeks.HAMD,MBI,ADL,NIHSS and TCM Symptom rating scale were used to evaluate the depression and neurologic changes before and after treatment.In the meanwhile,the serum BDNF contents in the two groups were measured by ELISA and safety evaluation.2.Part of experimental study:?In vivo experiment:PSD rat model was established by using the classical method of the middle cerebral artery embolism and chronic unforeseeable mild stress combined with solitary nutrition,which were divided into sham-operation group,PSD model group,fluoxetine group,low,middle and high dose group.After 28 days'intervention,the behavioral changes of each group were compared.The expression levels of BDNF/TrkB-mRNA and SYN-?,SYNA and GAP-43 were detected by quantitative RT-PCR and immu nob lotting.The ultrastructure of hippocampal neuron synapses were observed by immunofluorescence staining and transmission electron microscopy.?In vitro experiment:BDNF/TrkB pathway inhibitor(K252a)was introduced into primary rat hippocampal neuron oxidative stress injury model,which was divided into three groups:Normal control group,H2O2 culture group,serum containing medicine+H2O2 culture group,serum containing medicine+K252a+H2O2 group,K252a+H2O2 group.The expression level of BDNF/TrkB pathway-related protein(gene)was detected by quantitative RT-PCR and immunoblotting.Results:1.The scores of HAMD,MBI,ADL,NIHSS and TCM syndrome were significantly higher in the treatment group than those in the control group after 12 weeks of treatment(P<0.01).The serum BDNF level in the treatment group was significantly higher than that in the control group(P<0.01).2.The learning and memory function of PSD model rats was improved after the intervention of high-dose Shenjingfuyuan Decoction.The expression of BDNF and TrkB gene in hippocampus was significantly higher than that in model group(P<0.01).The expression of SYN-? and SYNA in hippocampus neurons was significantly higher than that in model group(P<0.01).The synaptic density and postsynaptic density of hippocampal neurons in the high-dose SD group were significantly higher than those in the model group.3.After the primary rat hippocampal neuron was injured by H2O2,the BDNF-TrkB signal transduction protein could be effectively repaired by the serum intervention containing the medicine of Shenjingfuyuan Decoction.Compared with the H2O2 group,the SYN I and SYNA protein levels were significantly increased(P<0.01).After the signal transduction was blocked by K252a,the repair effect was reduced,and the related protein levels were not significantly changed.Conclusion:Shenjingfuyuan Decoction can effectively improve the depression of PSD patients,and it can significantly improve the neurologic recovery and the ability of daily living of patients.Its mechanism may be related to the regulation of BDNF/TrkB signal pathway,the expression of synaptophysin I and SYNA in hippocampus,and the enhancement of synaptic plasticity of hippocampal neurons.