Gut-brain axis important in creation of new brain cells
29 June 2021
Researchers from the UK Dementia Research Institute working in collaboration with scientists across the world, have found mice without gut bacteria make fewer new brain cells compared to mice who do have gut bacteria.
It also suggests the ability to break down a substance called tryptophan is important in the gut-brain axis for creating new brain nerve cells.
The scientific journal PNAS, published the findings today (Monday 28 June).
What Alzheimer’s Research UK’s expert said:
Dr Susan Kohlhaas, Director of Research at Alzheimer’s Research UK, said:
“While we begin to lose nerve cells in the brain from early adulthood, new nerve cells continue to grow in certain parts of the brain, including the hippocampus — a region involved in memory. There has been conflicting evidence about the extent to which adults can grow new nerve cells in the brain, and the factors that affect this process.
“As surprising as it may be, current research implicates the environment of the gut in the health of our brains. In this early-stage research, mice unable to process a molecule called tryptophan in the gut did not produce as many new nerve cells as the mice which could. It’s worth bearing in mind that this research didn’t look at mice with features of Alzheimer’s but does point towards a role for the gut in brain health.
“In recent weeks we have seen drug regulators approve the first treatment designed to slow Alzheimer’s disease and protect nerve cells from damage, but we need to remain focussed on creating a diverse pipeline of potential drugs. Understanding the creation of new brain nerve cells could be one of the keys to unlocking new treatment approaches and the UK Dementia Research Institute is at the forefront of this effort, with studies like this.
“While this study was conducted in mice, the make-up of our gut bacteria is influenced by both genetics and our lifestyle, so it is one of a number of potential dementia risk factors that we could influence by leading a healthy life. To maintain a healthy brain as we age the best current evidence suggests that we keep physically fit, eat a balanced diet, maintain a healthy weight, not smoke, only drink within the recommended limits and keep blood pressure and cholesterol in check.”
PNAS: Tryptophan metabolizing gut microbes regulate adult neurogenesis via the aryl hydrocarbon receptor