Stress-related protein speeds progression of Alzheimer's disease

by Anne Delotto Baier
Dr. Chad Dickey of the USF Health Byrd Alzheimer’s Institute was principal investigator for the study.

A stress-related protein genetically linked to depression, anxiety and other psychiatric disorders contributes to the acceleration of Alzheimer's disease, a new study led by researchers at the University of South Florida has found.

The study is published online today in the Journal of Clinical Investigation.

When the stress-related protein FKBP51 partners with another protein known as Hsp90, this formidable chaperone protein complex prevents the clearance from the brain of the toxic tau protein associated with Alzheimer's disease.

Under normal circumstances, tau helps make up the skeleton of our . The USF study was done using , mice genetically engineered to produce abnormal like that accumulated in the brains of people with Alzheimer's disease, and post-mortem human Alzheimer's brain tissue.

The researchers report that FKBP51 levels increase with age in the brain, and then the stress-related protein partners with Hsp90 to make tau more deadly to the brain cells involved in memory formation.

Hsp90 is a , which supervises the activity of tau inside nerve cells. Chaperone proteins typically help ensure that tau proteins are properly folded to maintain the healthy structure of .

However, as FKBP51 levels rise with age, they usurp Hsp90's beneficial effect to promote tau toxicity.

This video is not supported by your browser at this time.
Dr. Dickey explaining the role of chaperone proteins in regulating tau.

"We found that FKB51 commandeers Hsp90 to create an environment that prevents the removal of tau and makes it more toxic," said the study's principal investigator Chad Dickey, PhD, associate professor of molecular medicine at the USF Health Byrd Alzheimer's Institute. "Basically, it uses Hsp90 to produce and preserve the bad tau."

The researchers conclude that developing drugs or other ways to reduce FKB51 or block its interaction with Hsp90 may be highly effective in treating the tau pathology featured in Alzheimer's disease, Parkinson's disease dementia and several other disorders associated with memory loss.

A previous study by Dr. Dickey and colleagues found that a lack of FKBP51 in old mice improved resilience to depressive behavior.

More information: Blair, L. et al. Accelerated neurodegeneration through chaperone-mediated oligomerization of tau, Journal of Clinical Investigation, Vol. 123, No. 10. DOI: 10.1172/JCI69003.

Related Stories

Protein inhibitor helps rid brain of toxic tau protein

Sep 29, 2009

Inhibiting the protein Hsp70 rapidly reduces brain levels of tau, a protein associated with Alzheimer's disease when it builds up abnormally inside nerve cells affecting memory, neuroscientists at the University ...

Recommended for you

Xenon exposure shown to erase traumatic memories

21 hours ago

McLean Hospital researchers are reporting that xenon gas, used in humans for anesthesia and diagnostic imaging, has the potential to be a treatment for post-traumatic stress disorder (PTSD) and other memory-related disorders.

Stop and listen: Study shows how movement affects hearing

22 hours ago

When we want to listen carefully to someone, the first thing we do is stop talking. The second thing we do is stop moving altogether. This strategy helps us hear better by preventing unwanted sounds generated ...

User comments