Beta-asarone attenuates beta-amyloid-induced apoptosis through the inhibition of the activation of apoptosis signal-regulating kinase 1 in SH-SY5Y cells.

Beta-amyloid (Abeta) toxicity has been postulated to initiate synaptic loss and subsequent neuronal degeneration seen in Alzheimer's disease (AD). We previously demonstrated that beta-asarone improves cognitive function by suppressing neuronal apoptosis in vivo. In this study, we assessed the neuroprotective effects of beta-asarone against the toxicity of Abeta in relation to the mitochondria-mediated cell death process, and to elucidated the role of the ASK1/MKK7/JNK and mitochondrial pathways in beta-asarone-induced neuroprotection in SH-SY5Y cells. Our results show that beta-asarone afforded protection against Abeta-induced toxicity by inhibiting apoptosis in SH-SY5Y cells. This result was also confirmed by caspase-9 and caspase-3 activity assays. Expression of p-ASK1, p-MKK7, p-JNK, Bax, Bad, and cytochrome c release decreased after pretreatment with beta-asarone in SH-SY5Y cells exposed to A1-42. Interestingly, these effects of beta-asarone against Abeta1-42 insult were enhanced by ASK1 siRNA. These findings suggest that beta-asarone prevents Abeta1-42-induced neurotoxicity through attenuating neuronal apoptosis, and might be a potential preventive or therapeutic agent for AD.