Effects of daidzein on expressions of BDNF and NPY in hippocampus rats with chronic stress depression and non-specific immune regulation / 中国免疫学杂志

ABSTRACT

Objective:To investigate the effects of Daidzein on behavior of chronic stress depression rats and the expression of hippocampal brain-derived neurotrophic factor ( BDNF ) , neuropeptide Y ( NPY ) and non-specific immune regulation.Methods: 40 healthy adult male SD rats with body weight(210±19)g,clean grade,were chosen and fed with 1%sucrose solution for 4 d to change drinking habits.On the fifth day rats were subjected to water deprivation for 24 h without fasting.On the sixth day rats were fed with 1%surcrose solution.4 h later, preference of 1% surcrose solution was examined.According to the 1% sucrose solution preference and weight rats were randomly divided into 4 groups,normal control group(CG),model control group,(MG),fluoxetine group(FG,10.0 mg/kg),daidzein group(DG,80.0 mg/kg).At the same time of establishing model,rats were administered orally once a day for 32 d.The depression model was established by chronic unpredictable mild stress model and separation.The behavioral changes of the rats were observed, and expression of BNDF in hippocampus and NPY was measured by Western blot technology and immunohistochemistry.It was observed the proliferation function of lymphocytes,spleen index,the number of peripheral blood leukocytes and antibody-secreting cell function.Results: Compared with the normal control group(CG),the weight of rats with chronic stress protocol was lower, 1%sucrose consumption decreased,scores of rats in the open field test dropped significantly,the immobility time in the forced swimming test prolonged,the level of expression of BNDF and NPY decreased,all the differences above were statistically sig-nificant(P<0.01).Compared with model group,weight of rats in fluoxetine treatment group(FG) and daidzein treatment group(DG)in-creased,sugar consumption,scores in the open field test and the levels of expression of BNDF and NPY significantly increased,the differences were statistically significant( P<0.05 or P<0.01 ).The number of peripheral blood leukocytes and antibody-secreting cell function and proliferation of lymphocytes force in daidzein treatment group was significantly higher than the model group,daidzein dose spleen index was significantly higher than the model group(P<0.01).Conclusion: The daidzein can antagonize depressive symptoms in chronic stress mice,daidzein may increased content of BDNF in hippocampus and NPY protein, and enhanced the role of humoral immune response and lymphocyte proliferation in rats with chronic stress model.The mechanisms of antidepressant effects of daidzein might be related to the increase of content of BDNF in hippocampus and NPY protein and non -specific immune regulation.