Highly read on www.jneurosci.org in October

Prolonged stress may accelerate neurodegeneration in Alzheimer's disease by exacerbating the build-up of damaging proteins in the brain.

John Trojanowski at the University of Pennsylvania in Philadelphia and his colleagues studied mice that had been engineered to accumulate the proteins β-amyloid or tau in their brains, in a similar manner to that seen in people with Alzheimer's disease. They induced stress in these animals by housing them in isolation and periodically restraining them inside a tube. The stressed mice developed even greater amounts of brain β-amyloid or tau than non-stressed mice; they also had poorer memory and lost more brain tissue.

The researchers next treated the mice with a molecule that blocks a brain protein called corticotropin-releasing factor, which regulates the stress response. Stress no longer intensified disease symptoms in these mice, suggesting that blocking this pathway may impede neurodegeneration in people with Alzheimer's, say the authors.

J. Neurosci. 31, 14436–14449 (2011)