ABSTRACT
Objective:To analyze effects of tectorigenin on improving cognitive deficits in rats with vascular dementia(VD)by regulating Toll-like receptor 4(TLR4)/myeloid differentiation factor 88(MyD88)/nuclear factor-κB(NF-κB)signaling pathway.Methods:A total of 72 rats were randomly divided into sham operation group,model group,low,medium and high doses[25,50,100 mg/(kg·d)]tectorigenin groups and positive control group[piracetam 324 mg/(kg·d)],with 12 rats in each group.Except for sham operation group,VD models were replicated in other groups.After successful modeling,different doses tectorigenin groups and positive control group were administered intragastrically with different doses of tectorigenin and piracetam,while other groups were administered intragastrically with same volume of normal saline for 28 d.Spatial learning and memory ability were detected by Morris water maze.Neurotransmitter levels in hippocampus interstitial fluid were detected by high performance liquid chromatography-electro-chemical.Brain-derived neurotrophic factor(BDNF)and tyrosine kinase receptor b(TrkB)expressions in hippocampus were detected by RT-qPCR and Western blot.TLR4/MyD88/NF-κB pathway-related proteins in hippocampus were detected by Western blot.Results:Compared with sham operation group,escape latency was longer,while stay time in target area and times of crossing platform were lower in model group(P<0.05).Compared with model group,escape latency was shorter,while stay time in target area and times of crossing platform were higher in medium and high doses tectorigenin groups(P<0.05).NE,DA,5-HT and 5-HIAA levels in model group were lower than those in sham operation group(P<0.05),which were higher in medium and high doses tectorigenin groups than model group(P<0.05).Compared with sham operation group,BDNF and TrkB mRNA and proteins levels were lower,while TLR4,MyD88 and p-NF-κB p65/NF-κB p65 proteins levels were higher in model group(P<0.05).Compared with model group,BDNF and TrkB mRNA and proteins levels were higher,while TLR4,MyD88 and p-NF-κB p65/NF-κB p65 proteins levels were lower in medium and high doses tectorigenin groups(P<0.05).Conclusion:Tectorigenin can improve cognitive deficits in VD rats,which may be related to regulating TLR4/MyD88/NF-κB signaling pathway.