30 August 2013

Another protein claims to be the head of memory

Humans and animals have found a common memory protein

Kirill Stasevich, CompulentaSince scientists have more or less begun to understand what Alzheimer's disease is, it has been blamed for almost all age-related changes in the brain.

Everyone knows that memory weakens over the years, but memory loss is also one of the signs of Alzheimer's syndrome; as a result, age–related memory loss has often been interpreted as a variant of this disease, albeit very mild, very smoothed – a kind of Alzheimer's light.

Over time, however, it became clear that Alzheimer's disease and ordinary memory loss affect different neural circuits, although these circuits are located in the same structure – the hippocampus. But if the researchers described the molecular events in Alzheimer's disease in some detail (this is the formation of protein deposits from improperly folded molecules that harm neurons and eventually lead to cell death), then what happens with normal aging, with normal memory loss, remained unknown for a long time.

And it is these molecular events accompanying neural aging that researchers from Columbia University Medical Center (USA) describe in the journal Science Translational Medicine (Pavlopoulos et al., Molecular Mechanism for Age-Related Memory Loss: The Histone-Binding Protein RbAp48). In their work, Nobel laureate Eric Kendal and his colleagues used the brains of deceased people aged 33-86 years. It is clear that such an age spread just made it possible to see age-related changes. At the same time, the same changes were searched for in the brains of mice of different ages.

As a result, one gene was found whose activity plummeted with age, and this happened in both humans and mice. This gene encodes the protein RbAp48, which itself is involved in the regulation of genetic activity in the dentate gyrus of the hippocampus – exactly in the area where changes are believed to accompany "normal" memory loss. In another area of the hippocampus, which is involved in the development of Alzheimer's disease, no changes in the activity of the RbAp48 gene were detected.

A slice through the dentate gyrus (DG) of the hippocampus; the "memory protein" RbAp48 is yellow.
(Photo by Elias Pavlopoulos / Columbia University Medical Center.)

And this would be a simple correlation if scientists had not checked what would happen to cognitive abilities with artificial suppression of RbAp48 activity. The corresponding experiment was carried out, of course, not on humans, but on mice: the synthesis of this protein was turned off in young animals, after which they began to forget what they saw and were poorly oriented in space. That is, they behaved like old mice (and people). On the other hand, when this gene was stimulated in old mice, their memory improved.

Of course, this is not the first work that reports the discovery of a "memory protein". Such statements are made regularly, and such studies are published in very prestigious journals. The work described above is distinguished by the fact that its authors worked not only with animals, but also with human brains. In addition, they compared the described protein with aging.

However, in explaining what exactly this RbAp48 does in neurons, the researchers were not particularly original: as usual in such cases, the protein was attributed to the strengthening of synapses.

Prepared based on the materials of the Columbia University Medical Center: A Major Cause of Age-Related Memory Loss Identified.

Portal "Eternal youth" http://vechnayamolodost.ru30.08.2013

Found a typo? Select it and press ctrl + enter Print version

Related posts