The secret of how “super agers” have the mental agility of people decades younger has been discovered, according to The Telegraph.
Scientists have found that some elderly people are able to regenerate brain cells twice as quickly as healthy adults of the same age.
It has only recently been shown that people continue creating brain cells throughout their life, with researchers previously believing that humans were born with all the brain cells they will ever have.
The new research suggests that some people age without any signs of cognitive decline because their bodies are much better at renewing brain cells – a process known as neurogenesis – which protects them from diseases such as Alzheimer’s.
“Super agers had twice the neurogenesis of the other healthy older adults,” said Professor Orly Lazarov, of the University of Illinois at Chicago (UIC).
“Something in their brains enables them to maintain a superior memory. I believe hippocampal neurogenesis is the secret ingredient, and the data support that,” she said.
Lazarov added that, “This is a big step forward in understanding how the human brain processes cognition, forms memories and ages.”
A super ager is someone aged 80 or older who exhibits cognitive function that is comparable to an average person who is middle-aged.
To find out why their brains were still so nimble, scientists looked at donated brain samples from five groups: healthy young adults; healthy older adults; older adults with exceptional memory – or super agers; individuals with mild or early dementia; and those diagnosed with Alzheimer’s disease.
Researchers searched for three stages of developing brain cells; neuroblasts – the most primitive cells; adolescent stem cells on their way to neuronhood; and immature neurons, which are just shy of becoming functional.
They found that brains of older adults with super healthy cognition grow more new neurons than those of their peers, while those diagnosed with Alzheimer’s disease generated almost no new neurons.
Scientists hope that if they can find out what is driving the extra brain-cell development, they can create drugs or lifestyle interventions to boost healthy ageing and prevent diseases such as Alzheimer’s.
For example, previous research has shown that exercise produces a protein called cathepsin B which travels to the brain and triggers neuron growth.
“What’s exciting for the public is that this study shows the ageing brain is not fixed or doomed to decline,” said Ahmed Disouky, the first author of the study from UIC.
“Understanding how some people naturally maintain neurogenesis opens the door to strategies that could help more adults preserve memory and cognitive health as they age,” he said.
