Gut bacterium Roseburia inulinivorans linked to greater muscle strength in humans and mice
Researchers found that the presence of Roseburia inulinivorans in the gut correlates with higher muscle strength in adults and improves grip strength and fast-twitch muscle fibers in mice, suggesting potential for future probiotic approaches to combat age-related muscle loss.
A study published in the journal Gut reports that the gut bacterium Roseburia inulinivorans is associated with stronger muscles in both people and laboratory mice. Analysis of stool samples from 90 young adults (aged 18-25) and 33 older adults (aged 65 and over) showed that participants with detectable levels of the microbe had up to 29% higher hand-grip strength, while younger participants with higher abundances also performed better on leg-press, bench-press and VO₂ max tests. The researchers noted that other Roseburia species did not show the same relationships.
In a parallel animal experiment, mice whose gut microbiota were cleared with antibiotics received weekly doses of three different Roseburia strains for eight weeks. Only the group given R. inulinivorans exhibited a roughly 30% increase in forelimb grip strength and a higher proportion of type II (fast-twitch) muscle fibers in the calf muscle, compared with control mice.
The authors caution that the mouse findings do not prove causality in humans and that further long-term studies are required to determine whether boosting R. inulinivorans levels can prevent or reverse sarcopenia. They suggest the results support the concept of a gut-muscle axis and propose that the bacterium could be explored as a probiotic candidate for maintaining muscle health in older adults.
“Collectively, our findings provide robust evidence supporting a gut-muscle axis in which R. inulinivorans positively modulates muscle metabolism and muscle strength.”
“Its abundance appears to decline with advancing age, a period during which the prevalence of sarcopenia increases, suggesting a potential role for R. inulinivorans as a probiotic candidate for preserving muscle strength.”
