Effect and mechanism of fuzhisan and donepezil on the sirtuin 1 pathway and amyloid precursor protein metabolism in PC12 cells

The present study aimed to determine the effect and mechanism of fuzhisan (FZS) and donepezil on the SIRT1 signaling pathway and the metabolism of the amyloid precursor protein (APP) in PC12 cells. An experimental cell model of PC12 cells with A beta 25-35-induced neurotoxicity was established and cell proliferation was determined by the MTT assay following treatment with donepezil and FZS. In addition, cell apoptosis was determined using DAPI staining and light microscopy. Furthermore, western blot analysis and ELISA were utilized to evaluate the expression levels of associated APP, A beta 40, A beta 42, sAPP alpha, sAPP beta, ADAM10, sirtuin 1 (SIRT1) and forkhead box O (FoxO) protein. The results indicated that the cell model was successfully established and FZS protected the PC12 cells from the neurotoxic effects of A beta 25-35, in a similar effect to donepezil, in a dose-dependent manner. The expression of APP remained at the same level during the experimental period. The levels of A beta 40, A beta 42 and sAPP beta were downregulated, where as sAPP alpha, ADAM10, SIRT1 and FoxO expression levels were upregulated. In conclusion, FZS treatment attenuated the A beta 25-35-induced neurotoxicity in vitro. The neuroprotective mechanism of FZS was determined, including the induction of ADAM10 and SIRT1-FoxO pathway, which participated in the process of neuroprotection. The present study identified the neuroprotective function of FZS, which may protect against A beta-induced toxicity. Therefore, FZS may be used clinically as a beneficial therapeutic drug for the development or progression of Alzheimer's disease.