Twelve weeks of supplementation with a combination inulin and fructo-oligosaccharides (FOS) led to significant improvements in cognitive scores associated with memory in the study which included 36 twin pairs with one twin in the prebiotic group and the other in the placebo group.
"Prebiotics improved cognition but did not impact muscle strength and function, compared with placebo in a cohort of healthy older twins," the KCL researchers wrote in Nature Communications. "Our results demonstrate that cheap and readily available gut microbiome interventions hold promise for improving cognitive frailty in our ageing population."
It should be noted, however, that no benefits were observed for the study’s primary endpoint, muscle function, which may be due to the trial being too short, or underpowered by including too few participants, or a combination of other factors.
'A positive influence on cognitive function'
Commenting independently on the study’s findings, Glenn Gibson, professor of food microbiology and head of food microbial sciences at the University of Reading in the UK, and a world-renowned expert in prebiotics and probiotics, told NutraIngredients-USA: "This is a very well designed and reported study that addresses health parameters of gut microbiota modulation. The prebiotic nature of the intervention is confirmed through sophisticated analyses of the microbiome. Concomitant with this was a positive influence on cognitive function, which is a critical observation."
"Another health parameter, namely muscle integrity, as evidenced by chair-rise time, did not differ between test and placebo. This could have been due to trial duration. The volunteers participated remotely so more direct measures on muscle effects could well have been positive," Prof. Gibson added.
“Nevertheless, because gut microbiota mediated influences upon health were seen in terms of cognitive aspects, this is a very important study and another great output from the world class Twins cohort research at KCL."
Prebiotics are defined as "a substrate that is selectively utilized by host microorganisms conferring a health benefit". (Gibson, et al. Nat Rev Gastroenterol Hepatol, (2017) 14, 491–502)
Study details
The KCL researchers split the 36 twin pairs (aged 60 or older) and randomly assigned one twin to the placebo group and one twin to the prebiotic group to receive 7.5 g of the commercial prebiotic product Darmocare Pre by Bonsuvan. Both groups also received 3.32 grams per day of branched-chain amino acid protein powder, providing 1.66 grams of L-leucine, 0.83 grams of L-isoleucine and 0.83 grams of L-valine.
The researchers stated that the trial used remote video visits, online questionnaires and cognitive testing. Equipment and biological samples were shared via mail.
Results of the 12-week, placebo-controlled, double-blinded randomized controlled trial revealed that no benefits were recorded for muscle function, as measured by chair rise time. On the other hand, significant improvements in cognitive function were recorded for the prebiotic group compared to placebo.
"While this trial did not demonstrate improvement in skeletal muscle strength, we showed that gut microbiome modulation via prebiotic supplementation in the context of ageing-muscle research is feasible and well tolerated, with clear responses noted in the gut microbiota composition and function," the researchers wrote. "Future larger trials can examine the use of gut microbiome targeting interventions to overcome age-associated anabolic resistance."
Analysis of the gut microbiota revealed that twins in the prebiotic group experienced changes in 60 microbiome features over the 12 weeks of study, while only three were changed in the placebo group.
Unsurprisingly, the prebiotic group displayed significant increases in the relative abundance of Actinobacteria, and Bifidobacterium in particular compared to placebo. Bifidobacterium increases have been reported in many other inulin and/or FOS studies. However, unlike other prebiotic studies, the PROMOTe study didn’t observe any increases in Lactobacillus or Facealibacterium.
"We also illustrate the feasibility of remotely delivered trials for older people, which holds promise for future studies in this area, aiming to reduce the under-representation of older people in clinical trials and reduce research costs," the researchers concluded.
Probiota Americas
Prebiotics are one of the key themes for this summer's Probiota Americas. Taking place in Salt Lake City, June 10-12, Probiota Americas will also feature sessions focused on: Women's Health; The state of the market & retailer insights; Healthcare Practitioners; Microbiome modulation for companion animals; The rise of Tech; Regulatory Insights; and much more.
For more information and to register, click HERE.
Source: Nature Communications
15, 1859 (2024). doi: 10.1038/s41467-024-46116-y
“Effect of gut microbiome modulation on muscle function and cognition: the PROMOTe randomised controlled trial”
Authors: M. Ni Lochlainn, et al.