Fermented papaya preparation attenuates β-amyloid precursor protein: β-amyloid–mediated copper neurotoxicity in β-amyloid precursor protein and β-amyloid precursor protein Swedish mutation overexpressing SH-SY5Y cells

Recent studies indicate that the deposition of β-amyloid (Aβ) is related in the pathogenesis of Alzheimer’s disease (AD), but the underlying mechanism is still not clear. The abnormal interactions of Aβ with metal ions such as copper are implicated in the process of Aβ deposition and oxidative stress in AD brains. In the present study, we established a new AD model, using which we found that copper triggered the Aβ neurotoxicity in SH-SY5Y cells overexpressing the Swedish mutant form of human APP (APPsw) in a concentration dependent manner. Fermented papaya preparation (FPP) has shown high free radical scavenging ability in vivo and in vitro. FPP post-treatment increased cell viability and decreased the intracellular [Ca2+]i, reactive oxygen species (ROS) generation such as hydroxyl free radical and superoxide anion and nitric oxide (NO) accumulation in the cell. Our results also show that FPP prevents the cell apoptosis through bax/bcl-2 sensitive pathway.