Elucidating the Relationship Between Stress and Alzheimer Disease

Amyloid β (Aβ) is released during a stress response. To examine whether this increases the risk for developing Alzheimer disease (AD) in people with post-traumatic stress disorder (PTSD) as they get older, researchers used a mouse model of AD (knock-in alleles for amyloid precursor protein and presenilin 1) in which animals were or were not exposed to restraint stress.

AD-model mice have more anxiety-like behaviors, such as decreased exploration, than wild-type mice. The AD-model mice were susceptible to more-severe behavioral restriction after acute restraint stress and a later brief reminder. Similar to humans with PTSD, AD-model mice had elevated corticosteroid levels acutely after stress, followed by a chronically blunted hypothalamic-pi…