【摘要】 目的用Aβ25-35诱导HEK293细胞的Tau蛋白过度磷酸化建立Tau蛋白过度磷酸化的模型,探讨秦皮乙素(Esc)对该模型的作用及可能机制。方法采用不同浓度的Esc预孵HEK293细胞24 h,再用Aβ25-35诱导Tau蛋白过度磷酸化,Western blot检测Tau蛋白Ser396、Ser199位点磷酸化水平及GSK-3β磷酸化水平,以评价Esc对Aβ25-35诱导Tau蛋白过度磷酸化的影响及可能的作用机制。结果 10μmol/L Aβ25-35作用于HEK293细胞6 h,Tau蛋白Ser396和Ser199位点磷酸化水平分别是正常对照组的2.1和2.0倍,GSK-3β磷酸化水平增加至对照组的1.4倍,而预孵Esc(50、100、200μmol/L)24 h均可降低上述3个指标,其中200μmol/L作用最强,可使上述指标分别降低(57.2±5.3)%、(53.4±3.0)%和(59.3±2.1)%,与模型组比较差异均有统计学意义(P<0.05)。预孵10 mmol/L LiCl可使上述指标分别降低(39.4±5.6)%、(36.7±2.8)%和(39.6±2.6)%,与模型组比较差异有统计学意义(P<0.05)。结论Esc可降低Aβ25-35诱导的HEK293细胞Tau蛋白Ser396和Ser199位点过度磷酸化,该作用可能与Esc抑制GSK-3β活性有关。更多还原

【Abstract】 Objective To investigate the effects and mechanism of esculetin(Esc) on tau hyperphosporylation induced by Aβ25-35. Methods HEK293 cells were treated with Esc and then exposed to Aβ25-35. Western blot was applied to determine the expression of p-Tau(s396), p-Tau(s199), p-GSK-3β(Y216), Tau and GSK-3β. Results The levels of Tau phosphorylation at the sites of Ser396 and Ser199 reached the maximum value(about 2 times as control group) after6 hours exposure to Aβ25-35. 50,100 and 200 μmol/L of Esc treatment can markedly reduced Aβ25-35-induced hyperphosphorylation of Tau. The best inhibitory effect was observed at 200 μmol/L of Esc which makes the p-Tau(s396), p-Tau(s199) and p-GSK-3β(Y216) reduced by(57.2±5.3)%,(53.4±3.0)% and(59.3±2.1)%, respectively(P<0.05). 10 mmol/L LiCl made p-Tau(s396), p-Tau(s199) and p-GSK-3β(Y216) reduced by(39.4±5.6)%,(36.7±2.8)% and(39.6±2.6)%,respectively(P<0.05). Conclusions Esc could attenuate the Aβ25-35-induced hyperphosporylation of Tau at the sites of Ser396 and Ser199. This effect may be related with the inhibition of GSK-3β. These results suggest a potential therapeutic value for Esc in phosphorylation of Tau related diseases.更多还原