Study On The Antidepressant Effect And Mechanism Of Bai He Di Huang Decoction On Cums Depression Model Rats

ObjectiveThis study uses a CUMS combined with solitary-rearing method to create depression model SD female rats,with depression model rats as the research subjects.The antidepressant effect and mechanism of action of Bai He Di Huang Decoction will be studied using behavior,pathology,molecular biology,and immunological experimental techniques.This will provide an experimental basis for the clinical antidepressant application of Bai He Di Huang Decoction.Method1.Clean grade SD female rats were grouped according to the requirements of the experiment.They were then split into a blank group,model group,Bai He Di Huang Decoction high dosage group,Bai He Di Huang Decoction middle dosage group,Bai He Di Huang Decoction low dosage group,and a positive drug group(fluoxetine hydrochloride).Using chronic unpredictable mild stress(CUMS)combined with solitary-rearing methods,the rat model of depression was created.The weight,sugar water consumption,initial weight at the beginning of the experiment,and other behavioral indicators were used as observation indices to determine whether the depression rat models were established successfully.After successful establishment of the depression model,the Bai He Di Huang Decoction treatment was initiated and the behavioral study values were evaluated and recorded to observe the curative effect of the drugs.2.The hippocampus and mPFC tissues of each group of rats were harvested and the concentration of monoamine neurotransmitters and their metabolites were measured by ELISA technique.3.The hippocampus and mPFC tissues of each group of rats were harvested.Neuron apoptosis status was observed by TUNEL staining and Nissle staining,and gene expression of Caspase-3 in the brain was detected by PCR.4.The hippocampus and mPFC tissues of each group of rats were harvested.The protein expression of P-CREB,CREB,BDNF and BCL2 in the hippocampus and mPFC was studied by Western blotting.Result1.Behavior study:The body weight of the model group decreased markedly after 21 days into the experiment.The degree of sugar water preference decreased,and the central path path distance in the open field experiment became shorter.The high,middle,and low dosage Bai He Di Huang Decoction groups all showed obvious increases in weight,sugar water preference,and the central path path length also became longer.2.In regards to monoamine neurotransmitter amounts,Bai He Di Huang Decoction can alter the concentration of monoamine neurotransmitters and their metabolites and play an antidepressant effect.Compared with the control group,the model group concentrations of 5-HT,DA,NE and 5-HIAA in the mPFC and hippocampus tissues were significantly decreased(P<0.05),and the concentration of HVA in the mPFC region was decreased significantly(P<0.01).Compared with the model group,the Bai He Di Huang Decoction group and the positive drug group rats had significantly increased concentrations of 5-HT,DA,and NE in the above mentioned brain areas(P<0.05),the HVA in the mPFC region of the two groups increased(P<0.05),and hippocampal 5-HIAA levels also increased(P<0.05).Comparing the Bai He Di Huang Decoction group with the positive drug group,there were no significant differences between the neurotransmitter concentrations(P>0.05).Compared with the normal control group,the model group’s mPFC and hippocampal Glu concentrations were significantly increased(P<0.01),and the concentration of GABA was decreased(P<0.05).Compared with the model group,the Bai He Di Huang Decoction group and positive drug group rats’ mPFC and hippocampal Glu concentrations decreased(P<0.05),and the concentration of GABA increased(P<0.01).3.Pathological changes:Using TUNEL staining,the number of positive cells(apoptotic cells)in each group of rats was determined.The number of apoptotic cells in the model group increased significantly compared with that in the blank group,while the number of apoptotic cells in the Bai He Di Huang Decoction group and the positive drug group compared with the model group was significantly reduced.Nissle 1 staining showed that in the model group,rat brain regional structure was destroyed,cell numbers were significantly reduced,pyramidal cells and granule cells became disordered,cell neuronal membranes were ruptured,nuclei became smaller,and nerve cell vacuolation and nuclear pyknosis were noticeable.In the Bai He Di Huang Decoction group and positive drug group,the basic brain structures were mostly intact.The cells were arranged neatly,cell layers were abundant,and there was neuronal membrane integrity.Only a small amount of nucleus shrinkage,nerve cell vacuolation and nuclear pyknosis was observed.PCR analysis showed that the model group expression level of Caspase-3 mRNA was higher than that of the control group,with statistical significance(P<0.05).Compared to the model group,the levels of gene expression in the Bai He Di Huang Decoction and positive drug groups were significantly decreased and statistically significant(P<0.05).There was no significant differences between the control group,Bai He Di Huang Decoction group,and positive drug group(P>0.05).4.Western blot:Bai He Di Huang Decoction can significantly inhibit the reduction of neuron levels in the model depression rats.It can also stimulate the upregulation of the rat hippocampal and mPFC region’s Bcl-2,BDNF,CREB and P-CREB expression levels.This increases the protection of neurons and neuronal regeneration and results in an antidepressant effect.Conclusion:1.Behavioral studies showed that the antidepressant effect of Baihe Dihuang decoction was the best in the medium dose group.2.Baihe Dihuang Decoction achieves antidepressant effect by regulating the level of neurotransmitters.3.Baihe Dihuang Decoction can prevent and inhibit neuronal apoptosis,and its mechanism may be related to neuron protection.4.Baihe Dihuang Decoction can improve the expression of neurotrophic factor in the brain of rats,play a protective role in neurons and play an antidepressant effect.