Studies On The Effects Of Protocatechuic Acid On Poliferation And Differentiation Of Neural Stem Cells

Parkinson’s disease (PD) is a degeneration disease of the central neural system with high morbidity in the elders. For the therapy protocols, drug delivery, surgical operation and cell transplantation are the most effective ways nowadays. Neural stem cells (NSCs) have the property that can differentiate into dopaminergic neurons, which provide a source and present a hopeful prospect for replacement therapies especially in those PD patients with cell transplantation. However, several problems must be eliminated before clinical application in NSCs therapies, for instance, short supply in NSCs, low survival rate after transplantation and low differentiation rate of dopaminergic neurons, and so on.The main target of this paper is to investigate the effect of protocatechuic acid (PCA) on differentiation of NSCs. Using CCK-8kit to detect NSCs’survival and growth curve in monolayer culture, analysis the variation of apoptosis in NSCs treated with PCA at the concentration of0.06mM, immunohistochemical assay and fluorescence-activated cell sorter (FACS) test the quantity expression of Tyrosine hydroxylase (TH) and Nurrl positive cells. The expression of TH protein in the transfected cells was determined by Western blot analysis, and reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression of TH gene. Therefore the effect of PCA on the differentiation of NSCs into the dopaminergic neuron was studied in cell, protein and gene three different level. Then the mechanism of NSCs’differentiation on Nurrl pathway was also discussed.It was found that PCA can enhance NSCs’survivability and promote cell proliferation depend on time and concentration in monolayer culture. Compared with blank control group, the survival rate of NSCs increased142.5%±9.5%after treated4h. And it had an optimal effectiveness at inhibition apoptosis. PCA cannot induce NSCs differentiation used alone. The quantity of positive cells was significantly increased with a treatment of PCA combined with1%fetal bovine serum (FBS), TH protein and gene in the PCA combined with FBS group had an increase of180.67%and128.2%compared with blank control group. Meanwhile the quantity of Nurrl positive cells also had an increase of125%. So the effect of PCA on NSCs differentiation was closely related with Nurrl pathway. Furthermore PCA improved cell’survivability and inhibitted it apoptosis obviously. Meanwhile it made the antioxidant system activity.In conclusion PCA had an optimal effectiveness at proliferation and inhibition apoptosis of NSCs in monolayer culture. With the synergies of1%FBS, the PCA promote differentiation on NSCs into dopaminergic neurons and improve cells’survivability.