Effect of the modified wendan decoction on hippocampal astrocyte neurotrophy by regulating the TRP-KYN metabolic pathway in depression-model rats

Objective:To observe the effect of the modified Wendan decoction on the neurotrophic function of hippocampal astrocytes by regulating the tryptophan-kynurenine(TRP-KYN)neuroprotective metabolic pathway in depression-model rats.Methods:A total of 96 Sprague Dawley(SD)rats were randomly divided into the blank group,model group,sham surgery group,neurotoxicity blocker group(blocker 1 for short)group,decoction group,fluoxetine group,blocker 1 plus decoction group,and blocker 1 plus fluoxetine group.Depression in rats of all groups,except for the blank group,was generated by isolation combined with chronic unpredictable mild stress.After corresponding treatments of the rats in each group,the sucrose preference test was performed to evaluate the depressive behaviors of the rats.Serum levels of tryptophan(TRP),kynurenine(KYN),and kynurenic acid(KYNA)were detected via enzyme-linked immunosorbent assay(ELISA);the mRNA/protein expression of hippocampal astrocyte markers,glial fibrillary acidic protein(GFAP)and S100β,was detected via reverse transcription-polymerase chain reaction(RT-PCR)and immunohistochemistry.ELISA and RT-PCR were carried out to detect the levels/mRNA expressions of brain-derived neurotrophic factor(BDNF)and glial-cell-line-derived neurotrophic factor(GDNF),the nutrient secretions of hippocampal astrocytes in rats.Results:Compared to the blank group,the number of activities of rats was significantly reduced,and the GFAP expression in the hippocampus was significantly increased while the BDNF and GDNF expressions were significantly decreased in the model group.With the intervention of the modified Wendan decoction,the depression of rats was significantly improved,and the BDNF and GDNF expressions in the hippocampus were increased while the GFAP expression was decreased significantly in the model group.Conclusion:The modified Wendan decoction may improve the neurotrophic function of rats’hippocampal astrocytes by enhancing the neuroprotective function of the TRP-KYN pathway,thereby exerting an antidepressant effect.

Protective effects of modified Wendan decoction on hippocampal neurons in a rat model of depression

Objective:To study the effects of modified Wendan decoction on hippocampal neuron plasticity in a rat model of depression.Methods:Thirty-two rats were randomly divided into a blank control group,model group,traditional Chinese medicine(modified Wendan decoction)group,and Western medicine(fluoxetine)group.Isolation in conjunction with the chronic unpredictable mild stress(CUMS)method was used to replicate depression in rats from the experimental groups.The rats were treated for 28d following successful modeling.After treatment,transmission electron microscopy(TEM)was used to observe the ultrastructure of hippocampal dentate gyrus(DG)region in the rats.Enzyme-linked immunosorbent assay(ELISA)was performed to measure the levels of brain-derived neurotrophic factor(BDNF)and glial cell line-derived neurotrophic factor(GDNF)in hippocampal tissue.Additionally,RT-PCR was used to measure hippocampal BDNF and GDNF mRNA expression levels.Results:Compared to the control group,there was significant swelling,disordered cell arrangement,pyknosis,deepening of cytoplasmic staining in the hippocampal neurons,and severe hippocampal injury in the model group.Following treatment with the traditional Chinese medicine intervention,hippocampal neuronal injury was significantly alleviated,hippocampus structure was normal,and brain injury was significantly reduced in the depression rat model.Compared to the control group,hippocampal BDNF and GDNF mRNA levels in the model group were reduced(P<0.05).Compared to the model group,hippocampal BDNF and GDNF mRNA levels in the traditional Chinese medicine group increased(P<0.05).Conclusion:Modified Wendan decoction can increase hippocampal neurotrophic function and repair hippocampal neuronal injury,thereby preventing depression.

Effect of modified Wendan Decoction on enteric glia cells in depression model rats

Background:To explore the effect of modified Wendan Decoction on expression of enteric glial cells in depression model rats.Methods:Eighteen rats were randomly divided into the Blank group,Model group,and modified Wendan Decoction group(Decoction group).Depression was induced by isolation combined with chronic unpredictable mild stress in rats of all groups except for the Blank group.Changes of protein and mRNA expressions of the specific markers of enteric glial cells,glial fibrillary acidic protein,and S100 calcium-binding proteinβsubunit(S100β)in the stomach and colon tissues of rats in each group were detected respectively using immunohistochemistry and reverse transcription-polymerase chain reaction(RT-PCR).Results:Compared with the Blank group,the percentage of positive cells and the mRNA expression of GFAP and S100βwere increased in the Model group,and the difference was statistically significant(P<0.05);compared with the Model group,the percentage of positive cells and the mRNA expression of GFAP and S100βin gastrointestinal tissues of rats were decreased in the Decoction group,and the difference was statistically significant(P<0.05).Conclusion:The depression model rats developed hyperplasia,and enteric glial cells(EGCs)was activated.The mechanism of action of the Wendan Decoction on improving depression and promoting gastrointestinal motility may be achieved by inhibiting the hyperplasia and activation of EGCs in rats with depression.

Antidepressant mechanism of Jieyu No.1 decoction in a rat model of depression

Rats were subjected to unpredictable chronic stress and isolation-induced depression, and were then intragastrically perfused with Jieyu No.1 decoction or amitriptyline water solution for 21 consecutive days. Open-field test showed that Jieyu No.1 decoction and amitriptyline water solution significantly improved the abnormal behaviors of the depressed rats; it reduced plasma surfactant protein, corticosterone, and corticotropin releasing hormone levels, increased neuropeptide Y and somatostatin levels, and upregulated interleukin-ll3, -2, -6 protein expression in the hippocampal CA3 region. Somatostatin and interleukin-l[3 protein expression were negatively correlated with corticosterone level, and interleukin-113 protein expression was negatively correlated with corticotropin releasing hormone level. Results demonstrated that Jieyu No.1 decoction improved abnormal behaviors of depressed animals by regulating the function of the neuroimmunoendocrine system.