By transplanting microbes from young to old animals, it is possible to rejuvenate the brain and immune function, according to recent research on mice.

The findings could lead to new therapeutic avenues in microbial-based interventions for  slowing down brain aging and associated cognitive problems.

The study was conducted by APC Microbiome Ireland at University College Cork (UCC), and introduced an approach to reversing aspects of aging-related deterioration in the brain.

“It adds further evidence for the importance of maintaining a healthy microbiome as we age. This needs to be taken into account in policy developments for guidelines on healthy aging,” John Cryan, lead researcher at APC and vice president for research & innovation, UCC tells NutritionInsight.

Working with a controlled situation of mice that have defined genetics, diets and microbiome is very different from looking at humans. Therefore, caution is needed in not over-interpreting these findings yet, he notes. 

The aging process causes significant changes in the microbiota, related to decreased health and frailty in the elderly.

“We are not advocating fecal transplants for people who want to rejuvenate their brain, but what these studies point toward is a future where there will be a focus on microbiota-targeted interventions that will promote optimum gut health and immunity to keep the brain young and healthy.”

Microbiome potential explored
For almost a decade, there has been accumulating evidence that the microbiome composition changes with age, comments Cryan. However, it remained unclear whether the microbiota itself was causally responsible for slowing brain aging, which is where this current study comes to the fore.

Fecal microbiota transplantation was conducted from either young (three to four-month-old) or old (19 to 20 months old) donor mice into old recipient mice.

Transplant of microbiota from young donors reversed aging-associated differences in peripheral and brain immunity and the hippocampal metabolome and transcriptome of aging recipient mice.

Finally, the young donor-derived microbiota attenuated selective age-associated impairments in cognitive behavior when transplanted into an aged host. 

Industry players have previously highlighted the significance of the microbiome on health. In this space, an ADM expert predicted  microbiome research will lead to advancements around the gut-brain axis over the next five years.

As the global population is aging, industry players are honing in on healthy aging strategies. For example, the UK government is making £1 billion (US$1.4 billion) funding available to life science companies to address mental health and aging as well as dementia.