Amyloid-β from People with Alzheimer Disease Is Neurotoxic

Nearly 20 years ago, Journal Watch alerted readers to a then-controversial basic science discovery: Amyloid-β protein (a component of Alzheimer disease [AD] plaques) is neurotoxic and might, therefore, be the cause of AD (JW Nov 2 1990). Hotly debated at first, this hypothesis now is accepted widely, although other molecules (e.g., tau, apolipoprotein E4, presenilins) also are involved. However, most of the evidence for amyloid-β’s neurotoxicity comes from experiments in which amyloid-β is synthesized or produced in cell culture.

In a new study, researchers extracted soluble amyloid-β directly from the brains of people with AD. These extracts (but not extracts from the brains of people with 1 of 2 types of non-Alzheimer dementia) damaged syn…