Protective Mechanism Of Igf-1 On Mpp~+ Induced Neurotoxicity In Pc12 Cells

Parkinson disease,PD is the one of the most common Neurodegenerative diseases in the middle aged and the elder. The neuropathological changes of Parkinson disease may be associated with the loss of nigrostriatal system of dopamine (dopamine, DA) neuron. Recent study suggests that, the loss of DA neurons may be related of apoptosis. Insulin-like growth factor -1 is an important multi-function regulation factor of proliferation, which could regulate cell differentiation and proliferation and is considered to have the ability of inhibition apoptosis. Moreover, the neuroprotective function of IGF-1 was accepted by Scientific community. However, the protective effect of IGf-1 on MPP induce pc12 cells apoptosis is not yet clear. In this study, we treated PC12 cells with MPP to prepare the cell model of PD, then investigated the effect of GSK-3βand AKT on the protective from MPP induce pc12 cells apoptosis。 The part one Establishment of the model cell of PD using MPP~+ induced pc12 cells apoptosisThe cell viability of different concentration MPP treatment was determined using MTT assay. The results showed that the viability of pc12 cells was gradually decreased with the increased concentration of MPP.The active caspase-3 protein levels of different time points were analyzed by western-blot. The results showed that the active caspase-3 levels were reached peak at 4 h by MPP treatment.The apoptosis induced by MPP was observed by Hoechst 33258 staining method in PC 12 cellsThe part two Protective mechanism of IGF-1 on MPP~+ induced neurotoxicity in PC12 cellsThe MTT was be used to observe the change of PC12 cells viability when they were protected by IGF-1 with different concentrations,the result show that IGF-1 can protect PC12 cells,it increased the PC12 cells'survivial rate.The inhibition of apoptosis which induced by MPP~+ was observed when IGF-1by Hoechst 33258 and AO-EB staining method in PC 12 cells.To use the Western Blot assay the expression of AKT,GSK-3β, P-AKT and P-GSK-3βwhen the PC12 cells were exposed of both MPP~+ and IGF-1,the result show that the expression of P-AKT and P-GSK-3βhave consistant changes. To further confirm that GSK-3βand AKT involved in IGF-1 protection mechanisms,we treated cells with Specific inhibition agents of AKT and GSK-3β,and find that the specific inhibition agents of AKT could inhibit the protective effect of IGF-1, but the specific inhibition agents of GSK-3βcound protect PC12 cells from apoptosis induced by mpp.