Study On The Protective Mechanism Of Fomes Officinalis Ames Extract On Aβ_25-35 Induced Alzheimer Disease Rat And PC12 Cell Model

Objective:To investigate the protective effect of the different polarity extracts of Fomes officinalis Ames on the β-amyloid protein(Aβ25-35) induced Rat adrenal pheochromocytoma(PC12) injury; To investigate the influence and protective effects of Fomes officinalis Ames extractives on learning and memory disorders, damage of cholinergic system of Alzheimer’s disease rat model that induced by amyloid β-protein (Aβ25-35).Methods:1) The PC 12 cells were processed with different polarity extracts of Fomes officinalis Ames, PC 12 cells with the highest level of proliferation were selected with MTT method:2) In vitro Alzheimer disease model was established on PC 12 cells by Aβ25-35 induction; The cultured PC 12 cells were divided into five groups:normal control group, model group (Aβ25-35 injury group), low dose of the drug group (50μg/mL), drug dose (100μg/mL), the drug high dose group (200μg/mL), with MTT assay PC 12 cell viability; AinexinV-FITC/7-AAD double staining flow cytometry apoptosis; the expression level was detected by RT-PCR bax and bcl-2 gene mRNA; Western blot assay bax and bcl-2 protein expression 3) In vivo, the aggregated state Aβ25-35 (11.5μmol/L) injection in rat brain hippocampus side rat AD model rats were detected by Morris water maze learning and memory abilities; observation of pathological changes yuan nerve of rats with HE staining; using biochemical methods to detect the rat brain homogenates AchE activity of; by immunohistochemical staining of the brain tissue of rat ChAT expression changes. Results:Among the different polarity extracts of Fomes officinalis Ames, the ethyl acetate extract can promote the proliferation of PC 12 cell. The difference has statistical significance (P<0.05); 2.Cell viability of Aβ25-35-induced PC-12 cells decreased (44.73±10.14)% and the apoptosis rate increased (19.6%). The ethyl acetate extract of Fomes officinalis Ames could effectively alleviate the cell inhibition induced by the Aβ25-35,increase the cell viability (64.36±4.00)% and decrease the apoptosis rate (6.1%); RT-PCR result shows that after the PC-12 cells was induced by Aβ25-35, the bax gene expression was up-regulated, the bcl-2 expression was down-regulated; western blot result shows that the bax gene expression was down-regulated significantly, the bcl-2 expression was up-regulated significantly; 3) Compared with the model group, the escape latency of the rats that in the group of high, medium and low dose of Fome s officinalis A mes extractives was significantly shortened, The difference has statistical significance (P <0.05). The residence time in target quadrant were significantly prolonged. The number of crossing the platform times was increased. The number of nerve cells in hippocampus increased obviously. And decreased the AchE activity in brain tissue and increased ChAT activity in AD rat model. Conclusion:1) The ethyl acetate extract of Fomes officinalis Ames promote PC 12 cell growth and proliferation:2) The ethyl acetate extract of Fomes officinalis Ames has protective effect on the Aβ25-35 induced cell injury; 3) Fomes officinalis Ames extractives can improve the disability of learning and memory of AD rats that induced by Aβ25-35. And reduce the toxic effects of Aβ25-35 on neural cells by reducing the activity of AchE and increase the activity of ChAT.