摘要
目的观察人参皂苷Rgl对阿尔茨海默病（AD）大鼠脑片模型中磷酸化tau蛋白（P-tau）及钙调神经磷酸酶（CaN）表达的影响，探讨人参皂苷Rgl是否通过上调CaN表达从而抑制AD模型大鼠脑片tau蛋白磷酸化。方法制备5周龄雄性SD大鼠脑片（含皮质和海马），随机分为4组：对照组、模型组和人参皂苷Rgl组，人参皂苷Rgl＋他克莫司（FK506）（一种CaN抑制剂）组，每组10张脑片。各组脑片首先置于人工脑脊液中孵育1h，之后人参皂苷Rgl组和人参皂苷Rgl＋FK506组分别加入人参皂苷Rgl作用2h，然后除对照组外的各组分别加入冈田酸作用3h。干预结束后脑片经多聚甲醛固定后做冰冻切片，采用免疫组织化学染色、图像分析技术等方法检测各组大鼠脑片P-tau、CaN的表达水平。结果与对照组比较，模型组各脑区P-tau表达水平增加（P〈0．05），CaN表达水平减少（P〈0．05）；与模型组比较，人参皂苷Rgl组各脑区P-tau表达水平减少（P〈O．05），CaN表达水平增加（P〈0．05）；与人参皂苷Rgl组比较，人参皂苷Rgl＋FK506组P-tau表达水平增加（P〈0．05），CaN表达水平减少（P〈0．05）。结论人参皂苷Rgl可能通过上调CaN蛋白表达途径抑制AD大鼠脑片模型tau蛋白磷酸化，从而发挥抗痴呆作用。
Objective To determine the effect of ginsenoside Rgl on the expression of phosphorylated tau protein（P-tau） and calcineurin （CAN） in a rat brain slice model of Alzheimer＇s disease （AD） induced by okadaic acid （OA）, and to investigate whether gensenoside Rgl inhibits tau phosphorylation through up-regulating CaN in the process. Methods Brain slices （containing cerebral cortex and hippocampus） in 400μm thickness were obtained from 5-week-old SD rats, and then randomly divided into control, model, ginsenoside Rgl and ginsenoside Rgl ＋ tacrolimus （FK506, CaN inhibitor） groups, with I0 slices in each group. All these brain slices were cultured with artificial cerebrospinal fluid （ACSF） firstly, and then ginsenoside Rgl with or without FK506 was added into the ACSF of the corresponding groups for 2 h. Then, OA was administrated into ACSF of model, ginsenoside Rgl and ginsenoside Rgl＋FK506 groups separately for 3 h to induce tau phosphorylation to prepare AD model. There was no any intervention for the control group. Expression of P-tau and CaN proteins in brain slices as determined by immunohistochemical staining, and the results were analyzed by image acquisition and analysis system. Results Compared with the control group, the level of P-tau protein was significantly higher （P 〈 0.05） and that of CaN protein was obviously lower （P 〈 0.05） in the model group. Compared with the model group, the expression of P-tau was markedly lower （P〈 0.01） and that of CaN protein was remarkably higher （P〈 0.05） in the ginsenoside Rgl group. Compared with the ginsenoside Rgl group, the expression of P-tau was higher （P 〈 0.01） and the expression of CaN protein was lower （P 〈 0.05） in the ginsenoside Rgl＋FK506 group. Conclusion Ginsenoside Rgl inhibits tau phosphorylation probably by enhancing CaN expression in rat brain slice model of AD, and thus exerts anti-dementia effect.
出处
《中华老年多器官疾病杂志》
2014年第9期702-706,共5页
Chinese Journal of Multiple Organ Diseases in the Elderly
基金
陕西省科技攻关计划项目[2007K16-07（5）]
陕西省中医药管理局基金项目（2005030）
作者简介
通信作者：李玺，E-mail：lixi2100@solau．com
