Tau protein and memory: new data

Missing link found between tau and memory loss

LifeSciencesToday based on Gladstone News: Scientists Discover a Missing Link between Tau and Memory Loss

Scientists have long known that tau protein is directly related to the development of dementia, but it remained unknown exactly how it disrupts cognitive functions. In the article by Tracy et al. Acetylated Tau Obstacles KIBRA-Mediated Signaling in Synaptic Plasticity and Promotes Tauopathy-Related Memory Loss, published in the journal Neuron, researchers from the Gladstone Institutes describe how tau prevents the strengthening of interneuronal connections and thereby blocks the memorization of new information.

"Understanding how and why tau is toxic to neurons is the first step in eliminating or preventing the harm it causes in Alzheimer's disease," says study leader Li Gan, PhD. "In Alzheimer's disease models, we learned that tau destroys memory by reducing the level of another protein, KIBRA, necessary for the memorization process. Knowing this, we can start looking for ways to increase the amount of KIBRA with drugs that block the harmful effects of tau."

Information is remembered when chemical signals strengthen the connections between neurons. To preserve this information, neurons physically change, recruiting more chemical receptors to the surface where connections (synapses) are formed. The purpose of this process is to amplify incoming signals. If the connections between neurons are weakened or lost, the same happens with memory.

In their study, the scientists found that in a mouse model of Alzheimer's disease, the accumulation of tau protein in neurons disrupts the ability of these cells to strengthen connections with other neurons, preventing the consolidation of new information. This is because the natural chemical process – tau acetylation, enhanced in Alzheimer's disease, leads to the movement of tau from its usual localization in neurons to synapses. In synapses, tau reduces the levels of another protein – KIBRA (KIdney/BRAin protein, kidney/brain protein). This process hinders the adaptation of neurons and the strengthening of connections between them. Increasing the level of KIBRA reverses the harmful effects of acetylated tau and restores the ability of cells to remember information.

The researchers found that the level of the KIBRA protein is reduced not only in mice, but also in patients with Alzheimer's disease, correlating with an increase in the level of acetylated tau, which confirms the clinical significance of this discovery.

"Our results suggest that KIBRA may be the missing link between tau and memory loss in Alzheimer's disease," says Tara Tracy, PhD, first author of the paper. "The next step is to determine exactly how acetylated tau causes a decrease in KIBRA levels, and also to find out if our data can help in the development of more effective treatments for Alzheimer's disease."

Portal "Eternal youth" http://vechnayamolodost.ru  04.04.2016