ABSTRACT
OBJECTIVE：To study the effects and mechanism of panaxadiol （PD） on Tau protein phosphorylation in the SH-SY5Y cells transfected with APP gene（APP-SH-SY5Y）. METHODS ：The target of PD and non-receptor tyrosine kinases Fyn was verified by molecular docking. SH-SY 5Y cells were cultured in vitro ，and the APP-SH-SY 5Y cell models and green fluorescent （GFP）-SH-SY5Y cell model （control cell ）was constructed. The expression of Aβ1-42 was detected so as to verify the success of APP-SH-SY5Y cell model. Taking GFP-SH-SY 5Y cells as control ，the effects of 5，10，20，30，40 μmol/L PD and 125，250， 500，1 000，2 000 nmol/L PP 2（Fyn inhibitor ，positive control ）on the survival rate of APP-SH-SY 5Y cells were detected by CCK-8 assay after treated for 24 h，so as to confirm the optimal concentration. The concentration of Ca 2 + ，the ratio fophosphorylated Tau protein （p-Tau）/Tau，phosphorylatedn Src（p-Src）/Fyn and phosphorylated glutamate receptor 2B（p-GluN2B）/ GluN2B were detected in APP-SH-SY 5Y cells after trated with the optimal concentration of PD and PP 2 for 24 h. RESULTS ：The results of molecular simulation docking showed that PD could target Fyn protein. Compared with GFP-SH-SY 5Y cells ，the protein expression of Aβ1-42 in APP-SH-SY 5Y cell were increased significantly （P＜0.01）. The optimal concentration of PD and PP 2 were 20 μmol/L and 500 nmol/L. The 20 μmol/L PD and 500 nmol/L PP 2 could increase the survival rate of the cells and reduced the concentration of Ca 2+，the ratio of p-Tau/Tau ，p-Src/Fyn，and p-GluN 2B/GluN2B. CONCLUSIONS：PD can reduce the the phosphorylation of Tau protein through inhibiting Fyn/GluN 2B signaling pathway.
ABSTRACT
OBJECTIVE@#To investigate the effect of osthole on the expression of amyloid precursor protein (APP) in Alzheimer's disease (AD) cell model and its mechanism.@*METHODS@#The SH-SY5Y cell with over expression of APP was established by transfection by liposome 2000. The cells were treated with different concentrations of osthole, and the cell viability was determined by MTT and lactate dehydrogenase (LDH) assay. The differentially expressed miRNAs with and without osthole treatment were detected by miRNA array, and the target genes binding to the differentially expressed miRNAs were identified and verified by databases and Cytoscape. After the inhibitor of the differentially expressed miRNA was transduced into cells, the changes of APP and amyloid β (Aβ) protein were determined by immunofluorescence cytochemistry, and the mRNA expression of APP was determined by RT-PCR.@*RESULTS@#The AD cell model with over expression of APP was established successfully. The results of MTT and LDH assay showed that osthole had a protective effect on cells and alleviated cell damage. miR-101a-3p was identified as the differentially expressed miRNA, which was binding to the 3'-UTR of APP. Compared with APP group, the expression of APP and Aβ protein and APP mRNA increased in the miR-101a-3p inhibitor group (all <0.01), while the expression of APP and Aβ protein and APP mRNA decreased in the cells with osthole treatment (all <0.01).@*CONCLUSIONS@#Osthole inhibits the expression of APP by up-regulating miR-101a-3p in AD cell model.