Role Of Autophagy In MPTP Chronic Parkinson’s Disease Mouse Model And Intervention Of Echinacoside

Objective:Based on the MPTP(1-Methyl-4-phenyl-1,2,3,6-tetrahy dropyridine hydrochloride)chronic Parkinson mouse model,we studied the protective effect of DA(dopamine)neurons by Echinaceae(Echinacea,abbreviated ECH)through autophagy pathway.The mechanism and possible signaling pathway of ECH in autophagy were observed and discussed.We were looking forward to provide scientific proofs and theoretical basis for the use of "warming kidney and nourishing the liver" method in treating clinical Parkinson disease.Methods:The 10-week-old C57BL/6J male mice with the body weight of 25-30g were included.To establish the MPTP chronic Parkinson mouse model,the mice were given Echinacoside(30mg/kg)/Selegiline(1mg/kg)for intragastric administration for 4 weeks.Meanwhile,at 1 hour after the administration they were given subcutaneous injection of MPTP 0.1 ml/10g for twice a week.Exercise retardation,balance coordination ability and gait abnormalities were evaluated by behavioral observation(climbing pole experiment,and gait analysis).The damage status of DA neurons in the SN(Substantia nigra)was analyzed by tyrosine hydroxylase(TH)immunohistochemistry.Protein immunoblotting was used to detect the protein expression level of the autophagy-related protein mTOR(Mammalian target of rapamycin),ASlin-1,P62,LC3-Ⅱ(Chain 3-Ⅱ),and protein expression levels of AS(a-synuclein),phosphorylated of PI3K(Phosphatidylositol 3-kinase)(Protein kinase B),and Atgl3(Anti-human Thymocyte Globulin 13).Results:The behavioral analysis suggested that ECH could reduce the total time of rod climbing(rod time and climbing time,P<0.05),but no statistically significant difference was found in the aspect of gait analysis(P>0.05).Immunohistochemistry suggested that echinacoside can reduce the DA damage of MPTP chronic Parkinson mice(P<0.01).Western blotting showed that the ECH could up-regulate the expression of Beclin-1(P<0.05),decrease the expression of P62(P<0.05),promote the expression of LC3-II(P<0.05),and decrease the expression of a-synuclein(P<0.05)in the brain of chronic model mice.However,PI3K,AKT,mTOR,and Atg13 phosphorylated protein expression levels did not show statistical difference(P>0.05).Conclusion:ECH plays a protective role to the mid-brain DA neurons of MPTP-induced chronic PD model mice through autophagy pathway.