Feng Fei, Li Yuanyuan, Huang Nanqu, Luo Yong
Department of Neurology, The First People's Hospital of Zunyi and Third Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China.
National Drug Clinical Trial Institution, The First People's Hospital of Zunyi and Third Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China.
PeerJ. 2019 Dec 10;7:e8219. doi: 10.7717/peerj.8219. eCollection 2019.
Icaritin (ICT) is a prenylflavonoid derivative from . ICT has been shown to have neuroprotective effects. We investigate how ICT affects secretion of amyloid precursor protein (APP).
We exposed APP-PS1-HEK293 cells to ICT to investigate its effect on beta-site amyloid cleaving enzyme (BACE)1. Cell viability was evaluated by MTT and lactate dehydrogenase (LDH) assays. The half-maximal inhibitory concentration (IC) of ICT for BACE1 was measured using fluorescence resonance energy transfer. Effects of ICT on the mRNA expression of APP were assessed by quantitative polymerase chain reaction, and protein expression was measured by western blotting and immunofluorescence.
Icaritin inhibited BACE1 activity and IC was 5.70 ± 1.09 μM. Compared with the control group, at ICT concentrations of 5 μM and 10 μM, the viability increased and LDH leakage decreased in APP-PS1-293 cells. Also, mRNA expression of A disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) increased, while that of BACE1 and presenilin-1 (PS1) decreased, upon ICT treatment. Western blotting and immunofluorescence confirmed that protein expression of ADAM10, BACE1 and PS1 showed the same trend. Expression of the APP fragments sAPPβ and C-terminal fragment β decreased, while that of sAPPα increased, upon ICT treatment. Expression of amyloid β peptides in APP-PS1-HEK293 cells was lower in ICT-treated groups compared with that in the control group.
Icaritin, as a BACE1 inhibitor, inhibits APP secretion in APP-PS1-HEK293 cells by impeding the amyloidogenic pathway.
淫羊藿素（ICT）是一种来源于……的异戊烯基黄酮衍生物。已表明ICT具有神经保护作用。我们研究ICT如何影响淀粉样前体蛋白（APP）的分泌。
我们将APP-PS1-HEK293细胞暴露于ICT中，以研究其对β-分泌酶（BACE）1的影响。通过MTT和乳酸脱氢酶（LDH）测定评估细胞活力。使用荧光共振能量转移测量ICT对BACE1的半数抑制浓度（IC）。通过定量聚合酶链反应评估ICT对APP mRNA表达的影响，并通过蛋白质印迹和免疫荧光测量蛋白质表达。
淫羊藿素抑制BACE1活性，IC为5.70±1.09μM。与对照组相比，在5μM和10μM的ICT浓度下，APP-PS1-293细胞的活力增加，LDH泄漏减少。此外，经ICT处理后，含解整合素和金属蛋白酶结构域蛋白-10（ADAM10）的mRNA表达增加，而BACE1和早老素-1（PS1）的mRNA表达减少。蛋白质印迹和免疫荧光证实，ADAM10、BACE1和PS1的蛋白质表达呈现相同趋势。经ICT处理后，APP片段sAPPβ和C末端片段β的表达降低，而sAPPα的表达增加。与对照组相比，ICT处理组中APP-PS1-HEK293细胞中淀粉样β肽的表达较低。
淫羊藿素作为一种BACE1抑制剂，通过阻碍淀粉样生成途径抑制APP-PS1-HEK293细胞中APP的分泌。
