Even moderate exercise helps keep the brain healthy

Scientists at the University of Queensland (UQ) say they have found that exercise helps keep the brain healthy and even moderate exercise directly increases the number of stem cells in the ageing brain.

The Australian researchers say new brain cells are created all the time, but the amount declines as people age and they have been able for the first time to demonstrate that moderate exercise significantly increases the number of neural stem cells in the ageing brain.

The neuroscientists, Dr Daniel Blackmore and his colleagues at the Queensland Brain Institute (QBI) say new brain cells are created all the time, but the amount declines as people age and despite the general belief that there are in the brain only a set number of neurons or brain cells, neuroscientists already know that, in healthy brains, the creation of new neurons is an ongoing and lifelong mechanism and it has also been known for more than a decade that the number of new neurons produced in the brain, slowly declines with age.

According to Dr Blackmore, scientists are interested in finding ways to stimulate the production of neurons to negate any decline brought about by age or disease and he says their findings suggest that moderate exercise, from early to late in life, can have a very positive effect.

The team found in controlled models of ageing, the number of neural stem cells produced by mice participating in voluntary exercise (running wheel) were significantly higher than in animals of the same age which did not exercise (no running wheel).

Dr Blackmore says investigations into how neural stem cell numbers are altered will without doubt increase the understanding of how the brain responds to its environment and this ultimately should allow scientists to discover how to harness the brain's regenerative capacity.

Dr Blackmore says the brain's ability, even at an advanced age, to respond in a positive manner is very exciting as it extends the time-frame in which manipulation is possible.

QBI Director Professor Perry Bartlett FAA says the research represents another significant understanding of why neural stem cells are so important to brain function and the research has produced the first experimental data that shows how the propensity of the brain to make new neurons through increasing the number of stem cells even in the aged animal, can be changed.

Professor Bartlett says it can now be shown that exercise directly causes an increase in the number of stem cells in the brain and as stem cells develop into neurons, a good supply of neurons is essential for good mental health.

The research is published in Stem Cells.