Page URL:

Gene activity decline behind 'senior moments'

2 September 2013
Appeared in BioNews 720

Age-related memory loss could be the result of low levels of protein in the brain, according to researchers at Columbia University Medical Center (CUMC), USA.

The team believes that the protein deficiency is due to decreased gene activity in the hippocampus - a part of the brain that is known to play a crucial role in memory.

The study, published in Science Translational Medicine, involved two research phases. First, the researchers looked at brain cells from an area of the hippocampus called the dentate gyrus in eight healthy adult brains.

'Until now, no one has been able to identify specific molecular defects involved in age-related memory loss in humans', said co-author Scott Small, Professor of Neurology and director of the Alzheimer's Research Center at CUMC.

They identified 17 genes that may be related to memory decay. The most significant changes were found to occur in a gene that controlled the production of the protein RbAp48, where a steady decline in expression was observed from the youngest to the oldest brain.

In order to establish the role of RbAp48 in age-related memory loss, the researchers blocked the RbAp48 gene in healthy young mice and measured their memory proficiency using novel object recognition and water maze memory tasks. They found that when RbAp48 was inhibited, they displayed the same symptoms of memory loss as older mice. When RbAp48 inhibition was stopped, their memory returned to its normal levels.

The researchers were also able to improve memory in older mice by increasing the expression of RbAp48 so that their performance was comparable to that of young mice.

One of the main aims of this study was to distinguish age-related memory loss from Alzheimer's disease.

'It's possible that other changes in the dentate gyrus contribute to this form of memory loss', said Dr Eric Kandel, from Columbia's Mind Brain Behaviour Institute. 'But at the very least, it shows that this protein is a major factor, and it speaks to the fact that age-related memory loss is due to a functional change in neurons of some sort. Unlike with Alzheimer's, there is no significant loss of neurons'.

Dr Simon Ridley, head of research at Alzheimer's Research UK, told the BBC that the findings of these studies are promising, but are not yet as 'clear-cut' in real life. 'Separating early changes in Alzheimer's from age-related memory decline in the clinic still presents a challenge, but understanding more about the mechanisms of each process will drive progress in this area', he said.

A Major Cause of Age-Related Memory Loss Identified
Columbia University Medical Center (press release) |  28 August 2013
Memory Protein Fades With Age
ScienceNOW |  28 August 2013
Molecular Mechanism for Age-Related Memory Loss: The Histone-Binding Protein RbAp48
Science Translational Medicine |  28 August 2013
Protein clue to old-age memory loss
BBC News |  29 August 2013
Scientists discover key to normal memory lapses in seniors
Reuters |  28 August 2013
1 December 2014 - by Chris Hardy 
Common variants of immune-related genes have been linked with memory performance...
30 September 2013 - by Rhys Baker 
Whether painful memories linger or fade may be down to the expression of a single gene, according to researchers at Massachusetts Institute of Technology (MIT), USA...
29 April 2013 - by Siobhan Chan 
Stem cell therapy has improved memory and learning in brain-damaged mice, according to a study in Nature Biotechnology...
20 August 2012 - by Dr Sophie Pryor 
Families with higher levels of a protein linked to inflammation may be at a reduced risk of dementia....
16 July 2012 - by Dr Linda Wijlaars 
A rare genetic mutation, found in about one percent of Icelanders in a recent study, appears to protect against Alzheimer's disease and age-related cognitive decline. It is the first mutation found to act in this way and could be a target for future drug therapy...
5 March 2012 - by Dr Maria Botcharova 
An enzyme associated with memory loss can be blocked to reverse symptoms of Alzheimer's disease in mice, a study has shown...
to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.