How desperate are you to prolong your youth – enough to have someone else’s poo put into your body? It doesn’t sound too glamorous, but scientists report that transplanting faeces from young mice to older mice reversed signs of aging in the gut, eyes and brain.
Intriguingly, they found the reverse was true as well: transferring poo from older to younger mice increased levels of inflammation, one of the hallmarks of aging. (You might want to give that one a miss.)
It’s all thanks to the multitudes of bacteria that inhabit our gut – and poo – whose existence we have increasingly unravelled and marvelled at in recent decades.
Through the microscope
Through an explosion of research into the trillions of microscopic organisms that live in the gut – collectively called the microbiome – we now understand they play key roles in our health. They are also associated with declining metabolism and immunity with aging.
To shed more light on this, scientists transferred gut microbes from old mice to healthy young mice and vice versa. They then investigated the impact on inflammatory features and associated declines that occur with age in the gut, brain and eyes – known as “inflammageing”.
They found that transplants from older mice caused a breakdown in the lining of the guts of their younger counterparts, allowing bacteria and other unwelcome substances to enter the bloodstream. Sure enough, this compromised immunity and triggered inflammation in their brain and eyes.
They found that immune cells associated with inflammation in the brain with aging were over-activated in the young mice that received their elders’ poo products, and impacted a protein needed for normal eyesight. Conversely, these markers were reversed in the older mice who received transplants from the younger mice, which were rich in beneficial bacteria.
Another similar study found specific effects on the brain with faecal transplants from younger to older mice with implications for cognitive decline. This included reversal of aging in the hippocampus, a key organ involved in learning and memory. Accordingly, the rejuvenated older mice learned to navigate mazes faster.
What about humans?
Before getting excited about improving maze navigational skills as the years tick by, the research is too premature to be translated to humans, and there are all sorts of unknowns about all the microscopic lifeforms in our poo.
But there are other ways to mature gracefully and maintain youthfulness despite the wrinkles, which include most importantly staying active and eating and sleeping well.
References
https://www.sciencedaily.com/releases/2022/05/220504082622.htm
