Ethyl ether fraction of Gastrodia elata Blume protects amyloid β peptide-induced cell death

Alzheimer's disease is the most common cause of dementia in the elderly. Recently, it has been reported that Alzheimer's disease is associated with cell death in neuronal cells including the hippocampus. Amyloid β-peptide stimulates neuronal cell death, but the underlying signaling pathways are poorly understood. In order to develop anti-dementia agents with potential therapeutic value, we examined the effect of the herbal compound Gastrodia elata Blume (GEB) on neuronal cell death induced by amyloid β-peptide in IMR-32 neuroblastoma cells. The fractionation of GEB was carried out in various solvents. The hydroxyl radical scavenging effect of the ethyl ether fraction was more potent than any other fractions. In cells treated with amyloid β-peptide, the neuroprotective effect of the ethyl ether, chloroform, and butanol fractions was 92, 44, and 39%, respectively, compared with control. Taken together, these results suggest that the ethyl ether fraction of GEB contains one or more compounds that dramatically reduce amyloid β-peptide induced neuronal cell death in vitro.