Experimental Study On Protective Effect Of Sodium Dichloroacetate On Vascular Dementia

Objective:Vascular dementia(VD)is a heterogeneous brain dysfunction that occurs after stroke and other types of brain tissue perfusion injury.It causes at least 20% of cases of dementia,which significantly reduces the patient's quality of life irreversible.Studies have shown that cerebrovascular injury and endothelial cell dysfunction are one of the main causes of dementia.Endothelial progenitor cells(EPCs)are important precursors of vascular endothelial cells for the recovery of vascular injury and endothelial cell function.Therefore,finding drugs to improve the function and quantity of EPCs is of great significance for the treatment of VD.Sodium dichloroacetate(DCA)is a mitochondrial pyruvate dehydrogenase kinase inhibitor that has potential vasoprotective effects and promotes brain regeneration following cerebral ischemia.This study aims to study the protective effect of DCA on VD and the mechanism of improvement of EPCs function,and provide new exploration ideas for the prevention and treatment of VD.Methods:The cerebral ischemia-reperfusion model was prepared by middle cerebral artery occlusion(MCAO),and the VD model was established after 21 days of breeding.Rats were randomLy divided into 5 groups: sham operation group,model group(VD),DCA low-dose group(50 mg/kg),DCA medium-dose group(100 mg/kg),DCA highdose administration group(200 mg/kg)was intragastrically administered 24 hours after cerebral ischemia-reperfusion,and was administered once every 24 hours,and the rats were continuously administered for 21 days.Morris water maze test was used to detect the cognitive function of each group of rats.TTC staining to detect brain atrophy area at different times.The pathological changes of brain tissue were detected by HE staining and Nissl staining.The expression of CD31 in brain tissue was detected by immunohistochemical.The levels of VEGF and bFGF in rat serum were detected by ELISA,and the number of EPCs in peripheral blood of each group was detected by flow cytometry.Establish a complete method for the identification and culture of BM-EPCs.In vitro DCA directly interfered with BM-EPCs and compared their functional differences.The functional differences(migration,adhesion,lumen formation)of BM-EPCs from different groups were compared.The expression levels of ROS and NO in BM-EPCs were detected by flow cytometry.The oxidative stress was detected by Western blot.Changes in protein levels of AKT,p-AKT,eNOS,GSK-3? and Nrf2 in the pathway.Results:1.Morris water maze test results showed that DCA can significantly improve the cognitive function of VD rat(The time of escape latency decreased significantly,P<0.01),and the results showed a dose-effect relationship.The dose of 50mg/kg improved the escape latency of VD rats(P<0.01),but the memory function of rats in space exploration experiment was poor(P>0.05),while the 100mg/kg and 200mg/kg dose groups Significant improvement in both the escape latency test and the space exploration experiment(P<0.01);TTC staining results indicate that DCA can improve the brain atrophy area of VD rats.The results of HE staining and Nissl staining showed that the pathological damage of brain tissue in VD group was obvious,such as edema,cell pyknosis,etc.,the structural integrity of hippocampus was damaged,and the CA1 area had obvious damage,in the DCA group,the pathological damage of the brain tissue was improved,such as the degree of edema decreased,the hippocampus structure was complete,and the damage in the CA1 area was significantly improved;Immunofluorescence results showed that DCA treatment significantly increased the number of cerebral angiogenesis in VD rats(P<0.01).2.DCA treatment can significantly increase the levels of VEGF and bFGF in serum of VD rats(P<0.05),and can significantly increase the number of EPCs in peripheral blood of VD rats(P<0.01).DCA in vitro intervention can significantly improve the function of BM-EPCs.BM-EPCs functional comparison experiments showed that compared with BM-EPCs in VD group,BM-EPCs migration and lumen formation were significantly improved in DCA treatment group(P<0.01),and adhesion function was significantly improved(P<0.05);The results of flow cytometry showed that the ROS level in BM-EPCs of VD rats in DCA treatment group was significantly decreased(P<0.05),and the level of NO was significantly increased(P<0.01).Western blot was used to detect the expression of AKT,p-AKT,eNOS,GSK-3? and Nrf2 in BM-EPCs of each group.Compared with the model group,DCA can increase p-AKT,eNOS and Nrf2 in BM-EPCs of VD rats.Expression(P<0.01)and decreased GSK-3? expression(P<0.05).Conclusion:1.DCA(100mg/kg,200 mg/kg)has an improved effect on cognitive function of VD rats and can promote cerebral angiogenesis in VD rats.2.DCA promotes angiogenesis by increasing the levels of VEGF and bFGF in the serum of VD rats and the number of EPCs in peripheral blood.DCA may improve BM-EPCs function in VD rats by modulating oxidative stress pathway-associated proteins.