RESUMEN
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.
RESUMEN
OBJECTIVE To study the effects of Dianxianqing granules on the tau protein in P301S mice by regulating mitophagy. METHODS Totally 36 P301S mice were randomly divided into model group， Dianxianqing granule group （12.48 g/kg）， donepezil hydrochloride group （positive control， 1.3 mg/kg）， with 12 mice in each group； another 10 C57BL6 mice were selected as control group. Administration groups were given relevant drug solutions intragastrically， and control group and model group were given constant volume of water intragastrically. The gavage volume was 20 mL/kg， once a day， for consecutive 5 months. During the experiment， the general condition of mice was observed in each group. After the last medication， the learning and memory ability was determined by Y maze test and Morris water maze test； HE staining was used to observe the morphological changes in brain tissue， and Nissl staining was used to observe the structure of neural cells and the number of Nissl bodies in cerebral tissue. Immunohistochemistry was used to detect the expressions of phospho-tau serine 202/threonine 205 （abbreviated as AT8） in brain tissue. Western blot assay was used to determine the expressions of mitophagy-associated proteins [PTEN-induced putative kinase-1 （PINK1）， Parkin， microtubule-associated protein 1 light chain 3B （LC3B）， p62]， synaptic-associated proteins [postsynaptic density protein-95 （PSD-95）， synaptophysin （SYP）， and growth-associated protein-43 （GAP-43）] and the phosphorylation of tau protein [expressed by the phosphorylation levels of serine 199 （Ser199） and Ser202] in brain tissue. RESULTS The mice in E-mail：lnzyxyqy2003@163.com model group showed symptoms such as white hair， decreased body mass， and lower limb paralysis， with incomplete hippocampal structures in their brain tissue， as well as incomplete cell membrane edges and cell structures； the spontaneous alternating response rate， the times of crossing platform， the number of Nissl bodies， the protein expressions of PINK1， Parkin， LC3B， SYP， GAP-43， and PSD-95 were decreased significantly， compared with control group； swimming latency （fourth and fifth day）， the protein expressions of AT8 and p62，the phosphorylation levels of Ser199 and Ser202 were increased or lengthened significantly， compared with control group （P＜0.05 or P＜0.01）. Compared with model group， the above symptoms and indexes of mice were improved significantly in administration groups （P＜0.05 or P＜0.01）. CONCLUSIONS Dianxianqing granules can effectively improve cognitive impairment in P301S mice，the mechanism of which may be associated with inducing mitochondrial autophagy， reducing the hyperphosphorylation of tau protein， up-regulating the expression of synaptic-associated proteins in brain tissue，and repairing damaged neural cells.