Effect Of Early Intervention With Herbal Effective Fractions On Cholinergic System And Brain Apoptosis Of APP Transgenic Mice

Objective:To discuss and explore the effect of early intervention with Chinese herbal formula(HuanNao YiCong Fang, HNYCF) effective fractions among such factors as behavior, morphous of the hippocampus, apoptosis of the nerve cells, related indicators of cholinergic system.To observe the effect on those factors treated with HNYCF effective fractions, explore the mechanism of HNYCF effective fractions' early intervention on this model and provide experimental evidence for clinical treatment on Alzheimer's disease.Methods:In this research,3 months old APP695V7171 transgenic mice(60) were randomly divided into model group,large dose HNYCF effective fractions group(HNYCF large dose group),small dose HNYCF effective fractions group(HNYCF small dose group) and positive control group(Donepezil hydrochloride group),each group 15 mice. the same genetic background of non-transgenic mice as the control group.HNYCF large dose group used HNYCF effective fractions 2.8g/kg·d; HNYCF small dose group used HNYCF effective fractions 1.4g/kg-d; Donepezil hydrochloride group used Donepezil hydrochloride 0.65mg/kg-d.The model group and control group set to equal volume of distilled water. After Continuous medication for 6 months such factors were measured:The Morris water maze and the passive avoidance test were used to detect the visual spatial learning and memory ability of eAch mouse.Morphous of the hippocampus were observed after HE stained by microscope. Quantity of apoptosis cells were measured by TUNEL.The expression of related controlling gene were analysed by immunohistochemistry.Determination the content of Ach, AchE, CHAT by ELISA.Results:1. In the space-searching test, HNYCF large,small dose group and Donepezil hydrochloride group all improved memory function of APP mice. The ratioin of swimming distance in the central area, the HNYCF large dose group were more than that in the model group(P<0.05).2. In the passive avoidance test,HNYCF large,small dose group and Donepezil hydrochloride group were found can improve memory function of APP mice, which can improve latency and reduce the number of errors(P<0.05,P<0.01).3. HNYCF large,small dose group and Donepezil hydrochloride group can lessen the impairment on morphous in the hippocampal area of mice.4.The related indicators of cholinergic system in hippocampus:HNYCF large,small dose group and Donepezil hydrochloride group can reduce the content of AchE meanwhile increase the activity of CHAT(P<0.01, P<0.05).HNYCF large,small dose group and Donepezil hydrochloride group can improve the content of Ach(P< 0.05).HNYCF small dose group no obviously change(P>0.05).The related indicators of cholinergic system in cortex:HNYCF large,small dose group and Donepezil hydrochloride group can increase the content of Ach(P <0.05).Donepezil hydrochloride group can reduce the content of AchE(P <0.05),HNYCF large,small dose group no obviously change(P>0.05).HNYCF large,small dose group can increase the activity of CHAT(P<0.05).Donepezil hydrochloride group no obviously change(P>0.05).5. HNYCF large,small dose group and Donepezil hydrochloride group can reduce the amount of apoptosis cells in hippocampus CA1 area (P<0.01, P <0.05).Up-regulate the protein expression of Bcl-2 and down-regulate the protein expression of Bax,Increase the ratio of Bcl-2/Bax in the hippocampus CA1 area of APP transgenic mice model(P<0.05,P<0.01).Conclusions:Early intervene by used HNYCF effective fractions can improve the learning memory ability and morphous of the hippocampus of APP transgenic mice model. The mechanism and channel might be related to HNYCF effective fractions could enhance function of cholinergic system, inhibit apoptosis.