Protective Effect And Mechanism Of Sodium Valproate Combined With Estrogen On Advanced Menopause Dementia Mice

Objective: Studies have shown that estrogen plays a protective role in Alzheimer's Disease(AD),however,Estrogen replacement therapy(ERT),which begins in late menopause is ineffective.This study was to investigate the effects of Valproic acid(VPA)combined with estrogen on the senile plaques,Tau protein,neurons and synapses in the brain of late postmenopausal APP/PS1 double transgenic mice.The results of this study will provide experimental evidence for the development and development of multi-targeted drugs for the prevention and treatment of AD,and provide new evidence for the implementation of individualized treatment options for gender-differentiated diseases.Methods: Thirty 3.5-month-old female APP/PS1 double transgenic mice were randomly divided into 6 groups after one month of bilateral oophorectomy(Ovariectomy,OVX),namely: saline control group(Control;intraperitoneal injection of the same amount of normal saline),VPA treatment group(intraperitoneal injection of VPA 30mg/kg·d),17-?estradiol(E2)treatment group(intraperitoneal injection of E2 2.4ug/d·d),Liquirtigenin(LG)treatment group(glyc LG 50ug/kg·d),VPA+E2treatment group(intraperitoneal injection of VPA 30mg/kg·d;intraperitoneal injection of E2 2.4ug/d·d)and VPA+LG treatment group(intraperitoneal injection of VPA 30mg/ Kg·d;stomached with LG50ug/kg·d).After 4 weeks of continuous administration,the aggregation and deposition of A? in the brain of mice were observed by Thioflavin S staining and immunofluorescence staining.The changes of dendritic spines in the brain of mice were observed by Golgi staining.The synaptic changes in the brain of mice were observed by transmission electron microscopy.The content of A?40 and A?42 was detected by ELISA.The content of protein related to A? production and degradation was detected by Western Blot,such as APP,PS1,BACE1,IDE,NEP,etc.The content of Tau protein and PHF1 was detected,and the content of mature neuron marker NeuN was detected.The levels of synaptic-associated proteins GAP-43 and PSD-95 were measured for GSK-3?,p-GSK-3?,ER?,ER? and SUMO1 on the signal transduction pathway.Results: Thioflavin S staining showed green fluorescent patches in the AD-associated regions of the brain.The number of green fluorescent plaques in the brain of mice in each drug treatment group was lower than that in the control group,and the reduction in the combination drug treatment group was more pronounced.Immunofluorescence staining results were consistent with Thioflavin S staining.Golgi staining was used to observe the changes of dendritic spines in neurons.It was found that the density of dendritic spines increased after drug treatment.The statistical difference in the rise in the treatment group was greatest.Transmission electron microscopy showed synaptic changes.The results showed that combined drug treatments increased synaptic density,restored synaptic gap width,increased synaptic activity length,and increased postsynaptic density(PSD)thickness.ELISA results showed that the levels of A?40 in each drug treatment group were lower than those in the control group.The levels of A?42 in each drug treatment group were lower than those in the control group.Western Blot results showed that there was no significantdifference in the expression levels of amyloid-? protein(APP)between the drug-treated groups and the control group.?-site APP cleavage enzyme(BACE1)and presenilin1(PS1)were lower in the drug-treated groups than in the control group.The expression levels of insulin-degrading enzyme(IDE)in each drug treatment group were higher than those in the control group,and there were statistical differences in the VPA+LG group and VPA+E2 group.Except for the E2 group,the expression of neprilysin(NEP)was statistically significant compared with the control group.There was no significant change in the expression of Tau protein in each drug treatment group compared with the control group,PHF-1 was decreased in each drug treatment group compared with the control group.The expression of NeuN in each drug treatment group was higher than that in the control group,and the combined drug treatment group was more significant,which was three times that of the control group.The expression levels of growth associated protein(GAP-43)were increased in all drug-treated groups compared with the control group,and the increase in the combination drug treatment group was statistically significant.The content of postsynaptic density 95(PSD-95)in each drug treatment group was not significantly different from that in the control group,and the increase in the combination drug treatment group was statistically significant.The expression of ER? was increased in all drug-treated groups compared with the control group.The ER? content of each drug treatment group was higher than that of the control group.The expression levels of SUMO1 were decreased in each drug-treated group compared with the control group,the VPA+E2 group and the VPA+LG group were significantly decreased.There was no significant difference in the expression level of GSK-3? between the drug treatment groups and the control group.The content of p-GSK-3?(ser9)in the drug treatment group was significantly higher than that in the control group,and it wassignificantly higher in the VPA+E2 group and the VPA+LG group.Conclusions:1.Sodium valproate combination with estrogen treatment significantly reduced A? aggregation and deposition in the brain of AD model mice by regulating A? production and degradation.2.Sodium valproate combined with estrogen treatment can significantly reduce the hyperphosphorylation of Tau protein in the brain of AD model mice.3.Sodium valproate combined with estrogen treatment can restore the number of mature neurons in the brain of AD model mice and restore synaptic plasticity.5.Sodium valproate combined with estrogen treatment exerted protective effects on AD model mice through the ERs-SUMO1/GSK-3?pathway.