Protective Effects of Crocin Against Beta-Amyloid Peptide-Induced CellApoptosis in PC۱۲ Cells Via the PI۳ K Pathway

Background: Crocin is a known compound with the antioxidant and anti-inflammatory propertieswhich may help to reduce the progression of neurological disorders. In this study, we aimed toinvestigate the protective effects of crocin on beta-amyloid peptide Aβ (۱-۴۰) and hydrogen peroxide(H۲O۲) induced neurotoxicity in PC۱۲ cells.Methods: PC۱۲ cells were pretreated with crocin anddonepezil (۵ and ۱۰ μM) for ۲ h and then treated with Aβ (۱-۴۰) (۲۵ μM) for ۲۴ h. In parallel, afterpretreatment with crocin (۵ and ۱۰ μM) and donepezil (۵ and ۱۰ μM) for ۲۴ h, cells were treatedwith H۲O۲ (۸۰۰ μM) for ۴ h. Finally, the cell viability and intracellular reactive oxygen species(ROS) generation were evaluated using AlamarBlue® and ۲', ۷'-dichlorodihydrofluoresceindiacetate (DCFH-DA), respectively. The western blot test was done to compare the protein levelof phospho SAPK/JNK, SAPK/JNK, PI۳ Kinase P۸۵, Phospho-PI۳ Kinase P۸۵, caspase-۳ andcytochrome c) cyt c).Results: Crocin and donepezil could significantly decrease the Aβ toxicityand ROS level. While treatment with Aβ increased Cyt c release from mitochondria to cytosol,cleaved form of caspase-۳ (۱۷ kDa) and activated form of SAPK/JNK p۴۴/۴ decreased theactivated form of PI۳ Kinase P۸۵ protein, indicating that crocin could significantly block theapoptosis initiated with Aβ.Conclusion: According to the results, crocin could be a promisingcandidate for further evaluations against the development of Alzheimer's disease through mitogenactivatedprotein kinases (MAPK) and the phosphatidylinositol ۳-kinase (PI۳K)/protein kinase B(AKT) signaling (PI۳ K/AKT) pathways.

Keywords:

Alzheimer's disease , beta-amyloid , crocin , hydrogen peroxide , donepezil , oxidativestress.