Neuroscientists at the University of Queensland’s Brain Institute (QBI) have made a major breakthrough in the fight against dementia, finding the chemical process that causes the growth of new nerve cells. The molecule fractalkine may be key to halting early dementia, helping stop or even reverse the cognitive decline in older people.
The breakthrough came after scientists discovered that exercise by mice caused the molecule fractalkine to activate neural precursor cells in the hippocampus – the brain structure responsible for specific types of learning and memory.
Perry Bartlett, a Professor of Neuroscience and the Director of QBI says:
“Ageing slows the production of new nerve cells, reducing the brain’s ability to form new memories.”
Dr Jana Vukovic explained that the research involved mice, an exercise wheel, and a revolving turntable, part of which was electrified and needed to be avoided. The young mice quickly learnt what to avoid. Older mice did not learn at all until they were given some exercise, then they also learnt. Jana says:
“What we saw was quite remarkable…There was a significant increase in the number of activated neural precursors which gives us reason to believe fractalkine is important for initiating the first step in the production process that gives rise to new neurons – the activation of the neural precursor cells…
Our research shows for the first time that the brain cells usually responsible for mediating immunity, microglia, have an inhibitory effect on memory during ageing…
Once the cells are activated they can respond to signals that instruct them to divide and produce new cells, and as such develop new memories and learning. This means that fractalkine may indeed present a potential pathway for development of future therapies..
The discovery was exciting because it found that older animals suffering cognitive decline showed much lower levels of fractalkine…
Until relatively recently, it was thought the adult brain was incapable of generating new neurons..
But work from Professor Bartlett’s laboratory over the past 20 years has demonstrated that the brains of adult animals, including humans, retain the ability to make new nerve cells…
The challenge is to find out how to stimulate this production in the aged animal and human where production has slowed.”
By mimicking the production of fractalkine, scientists might be able to delay or repair the onset of dementia in elderly patients by creating new neuron cells without the need for exercise. In future ageing brains may be stimulated by fractalkine, via a future pill or patch?
The research has been published in the Journal of Neuroscience.