London: In a unique study, researchers have found that fecal transplants could one day be used to reverse the cognitive decline that comes with ageing.
Cognitive decline is when a person has trouble remembering, learning new things, concentrating, or making decisions that affect their everyday life
The study, published in the journal Microbiome, shows how faecal transplants from older to younger mice altered their gut microbiome, which in turn impacted their spatial learning and memory.
The research team hope that reversing the procedure could one day see faecal transplantation used to combat cognitive decline among the elderly.
The previous research has shown that the ageing process may be linked with age-related changes in our gut microbiota.
“Recently, the existence of two-way communication between the gut and the brain – known as the ‘gut-brain axis’ – has emerged as an important player in shaping aspects of behaviour and cognitive function,” said study author David Vauzour from the University of East Anglia in the UK.
“We wanted to see whether transferring gut microbes from older to younger mice could affect parts of the central nervous system associated with ageing,” Vauzour added.
The research team performed faecal transplants from older adult mice to younger adult mice and then assessed the young adults for markers such as anxiety, exploratory behaviour and memory.
After the transplantation, the team found significant differences in the young mice’s microbial profiles.
While the young adults showed no significant changes in markers of anxiety, explorative behaviour or locomotor activity, they did show impaired spatial learning and memory as measured in a maze test.
These changes were paralleled by alterations in the expression of proteins associated with synaptic plasticity and neurotransmission, and changes to cells in the hippocampus part of their brains – responsible for learning and memory.
“Our research shows that faecal transplantation from an old donor to a young recipient causes an age-associated shift in the composition of gut microbiota,” Vauzour said.
The procedure had an impact on the expression of proteins involved in key functions of the hippocampus – an important part of the brain that has a vital role in a variety of functions including memory, learning but also in spatial navigation and emotional behaviour and mood.
In short, the young mice began to behave like older mice, in terms of their cognitive function.
“This work highlights the importance of the gut-brain axis in ageing and provides a strong rationale to devise therapies aiming to restore a young-like microbiota to improve cognitive functions and quality of life in the elderly,” said researcher Claudio Nicoletti from the University of Florence, Italy.