Researchers link Alzheimer's to lack of specific protein

August 16, 2011

A new clue to understanding one of the causes of Alzheimer's disease was unveiled in an article published Sunday (Aug. 14) in Nature Neuroscience online. Kara Pratt, a new faculty member in the University of Wyoming Neuroscience Center , is the study's lead investigator.

Neurons, the cells of the brain and the nervous system, are amazingly flexible and adaptable, says Pratt, who led the project as a post-doctoral researcher at the University of Washington School of Medicine.

When proteins receive a lot of information from other neurons, they compensate by turning down their synaptic strengths ("input gain"). Conversely, Pratt says, when stimulated at lower than normal frequencies, they turn up their synaptic strengths. This is a form of neural plasticity referred to as homeostasis, which allows neurons to function stably in the midst of extreme changes in activity levels.

She says in people with Alzheimer's disease, it has been hypothesized that may lose their flexibility. The most common way in which familial (inherited) Alzheimer' disease is inherited is by a mutation in a protein called presenilin.

The researchers found that neurons that do not have presenilin are not adaptable -- are unable to change their gain -- when activity levels are altered for long periods of time. Pratt says the researchers also tested the compensatory response in neurons from engineered to express a mutated form of presenilin. These neurons also failed to adapt to changing amounts of stimulation.

"Our experiments indicate that presenilin is essential for neurons to remain adaptable," Pratt says. "Lack of this type of adaptability could contribute to underlying Alzheimer's disease."

Pratt is setting up a laboratory in the UW Department of Zoology and Physiology to study forms of neuron adaptability and other forms of in the developing visual system of the African clawed frog tadpole.

Related Stories

Recommended for you

Placebo sweet spot for pain relief found in brain

October 27, 2016

Scientists have identified for the first time the region in the brain responsible for the "placebo effect" in pain relief, when a fake treatment actually results in substantial reduction of pain, according to new research ...

Team announces mapping of the mouse cortex in 3-D

October 27, 2016

The Allen Institute for Brain Science has completed the three-dimensional mapping of the mouse cortex as part of the Allen Mouse Common Coordinate Framework (CCF): a standardized spatial coordinate system for comparing many ...

Neuro chip records brain cell activity

October 26, 2016

Brain functions are controlled by millions of brain cells. However, in order to understand how the brain controls functions, such as simple reflexes or learning and memory, we must be able to record the activity of large ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.