The Effects Of PDTC On The Expression Of Bcl-xL In Chronic Parkinson's Desease Mouse Model By MPTP

Objective(1) To investigate the relationship of reduction of DA neurons in substantia nigra and Bcl-xL expression in a NF-κB pathway-dependent manner in the chronic Parkinson disease mouse model by MPTP.(2) To explore the role of nuclear factor kappa-B inhibitor—pyrrolidine dithiocarbamate(PDTC) in the prevention of Parkinson disease..MethodsThis study adopted chronic parkinsonism C57BL/6J mice after the administration of MPTP,which were randomly divided into three groups:control group,test group,prevention group,40 mice in each group.All mice mice were bred at the same condition.MPTP was administered intraperitoneally to test group with the dose of 25mg/kg for 5 weeks,2 times per week, control group was injected with the same volume of saline.prevention group were given intraperitoneal injection of PDTC with the dose of 40mg/kg first,and next were given intraperitoneal injection of MPTP in half an hour;after treatment,The changes of ethology and Morphological were determined in mice of three groups at different time,The expression of Bcl-xL was determined by RT-PCR and immunohistochemistry.The expression of tyrosine hydroxylas (TH) were analyzed immunohistochemically.What was analyzed①The expression of Bcl-xL and the time-dependent correlation induced by MPTP injection;The consistent relationship between the expression of Bcl-xL and decrease in number of dopaminergic neurons and behavioral response in chronic mouse model of Parkinson disease induced by MPTP.②The effects of nuclear factor-kappa B (NF-κB) inhibitor-pyrrolidine dithiocarbamate(PDTC) on expression of Bcl-xL and the number of nigral neurona.Results(1)Behavior observation results:compared with control group,the test group manifested abnormal behaviors such as trembling,dribble at the mouth,pilo-erection,motor disorders,and the time of pole climbing in test group was are increasing significantly(p<0.05).Contrasting to the test group,but Symptom of the prevention group was not apparent.(2)Morphologic examination change:after HE staining, compared with the control group,the number of TH positive neurons in SNc was decreasing significantly in the test group,and there was no difference between the prevention group and controls (p > 0.05).(3)Results of the immunohistochemistry SABC:The integral optical density (IOD) of test group at 12h and 24h were more than that of the control,which indicates that the Bcl-xL expression of test group was increasing.1w～2w,the Bcl-xL expression of test group decreased.At the corresponding time after the last MPTP injection, as compared with the control group,the TH-positive cells of test group decreased (P <0.05).At the 12h~24h in the test group, TH-positive cells were more than these of 1w~2w (P <0.05). Prevention group results contrasted with the test group.(4)The result of Bcl-xL mRNA by RT-PCR method:In comparison with the control group, The expression of Bcl-xL mRNA at 12h in the test group was obviously increasing(p<0.05),and its levels peaked at 24h;1w～2w,The expression of Bcl-xL mRNA was down-regulated(P<0.05),Prevention group received the opposite conclusion with the test group.Conclusion(1)These experiments suggested that expression of Bcl-xL played an important role in chronic mouse model of Parkinson disease induced by MPTP,which was regulated by NF-κB Signaling Pathway.(2)The results of this experiment implied that there was dual effects of NF-κB pathway on that expression of Bcl-xL,and this effect was time-dependent, but in the end leading to DA neuronal loss.(3) There was a significance in the prevention of Parkinson disease for nuclear factor kappa-B inhibitor—pyrrolidine dithiocarbamate(PDTC).