The Study Of Haowang Formula Improving Cognitive Impairment In AD Mice Models And Related Mechanism

Alzheimer's disease(AD),also known as senile dementia,is one of the most common types of neurodegenerative diseases,and a heavy burden on families and society with its high morbidity and mortality.However,since the efficacy of the mainstream AD drugs is not satisfying,it is urgent to discovery novel drugs for AD treatment.Multi-target approach such as Traditional Chinese Medicine(TCM)has been suggested to hold the promise for better treatment efficacy.According to TCM theory,Kidney Deficiency and Phlegm Disturbance is one of the most common patterns of AD.Therefore,Kidney reinforcement and phlegm clearance are important approaches for AD treatment.Haowang Formula(HWF),focusing on Kidney reinforcement and phlegm clearance,is an ancient formula prescribed by the famous Chinese Medicine master Sun Simiao in Tang Dynasty for the use of treating forgetfulness.However,there is a lack of research on the application of HWF in AD treatment.OBJECTIVE:To exam the therapeutic effect of HWF alleviating cognitive impairment in AD models and related mechanism.METHODS:1.Using scopolamine to induce cognitive impairment in ICR mice,and to evaluate the effect of HWF improving cognitive impairment on AD acute mice model.2.Using SAMP 8 mice to explore the cognitive enhancement effect and characteristics of HWF treating AD spontaneous mice model,and to explore its underlying mechanism.3.Using ICR mice to verify the importance of PKA in HWF treating cognitive impairment in AD model mice and improving cognitive ability in non-model mice.RESULTS:1.Scopolamine model mice displayed cognitive impairment in escape latency and times of crossing the platform in MWM.The treatment of HWF or donepezil significantly increased times of crossing the platform in MWM test.2.Compared to CTL,5-month old SAMP8 mice showed cognitive dysfunction with escape latency increased,times of crossing the platform and distance in target quadrant decreased in MWM.Novel object exploration index was also decreased in NOR.With 2 weeks of drug treatment,HWF distinctly increased times of crossing the platform and distance in target quadrant of mice in MWM,and increased the protein level of PKA.Donepezil,however,did not manifest any therapeutic effect;with 3 weeks of drug administration,both HWF and donepezil displayed therapeutic effect on escape latency,times of crossing the platform and new object recognition index.In hippocampus of SAMP8 mice,HWF and donepezil distinctly reduced the protein levels of TAU-ser404 by activating PKA-GSK3?-TAU pathway.It also reversed the down-regulation of PKA-CREB and its dowrmstream molecule BDNF and synaptic proteins including SYNAPSIN1,GluRl,and PSD95.However,HWF increased distance in target quadrant and showed better treatment effect on shortening escape latency than donepezil;with 3 weeks of drug administration and 1 week of withdrawl,in Morris water maze and Novel recognition test,the treatment effect of HWF did not fade.Donepezil,however,showed improvement in escape latency only.Furthermore,HWF can still upregulated the PKA expressions in the hippocampus of SAMP8 mice,Donopezil,however,failed to adjust.And the PKA expression of HWF group is significantly higher than that of Donepezil group.3.(1)On scopolamine mice model,HWF significantly increased number of crossings the platform and decreased the protein expression levels of phosphorylated TAU.PKA blocker H89 reversed or blocked the treatment effect of HWF(2)On non-model mice,HWF significantly increased times of crossing the platform in MWM and time in novel arm in Y-maze.It also up-regulated the protein levels of PKA,CREB and PSD95 in hippocampus.With PKA blocked by H89,the cognitive enhancement effects disappeared or significantly reversed.CONCLUSION1.HWF alleviated cognitive impairments in scopolamine model mice and SAMP 8 model mice2.The cognitive improvement effect of HWF is closely related to PKA-GSK3?-TAU mediated clearance of phosphorylated TAU and PKA-CREB mediated enhancement of synaptic plasticity3.The cognitive improvement effect of HWF relies on the activation of PKA.