BOSTON (Sept. 18, 2019)—A novel new study suggests that the gut microbiome has a role in mechanisms related to muscle strength in older adults. The work, led by researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts, is available as a pre-proof in advance of print in Experimental Gerontology.
The gut-muscle axis, or the relationship between gut microbiota and muscle mass and physical function, has gained momentum as a research topic in the last few years as studies have established that gut microbiota influences many aspects of health. While researchers have begun exploring the connection between the gut microbiome, muscle, and physical function in mice and younger adults, few studies have been conducted with older adults.
To gain insight into this population, the researchers compared bacteria from the gut microbiomes of 18 older adults with high-physical function and a favorable body composition (higher percentage of lean mass, lower percentage of fat mass) with 11 older adults with low-physical function and a less favorable body composition. The small study identified differences in the bacterial profiles between the two groups.
Similar bacterial differences were present when mice were colonized with fecal samples from the two human groups, and grip strength was increased in mice colonized with samples from the high-functioning older adults, suggesting a role for the gut microbiome in mechanisms related to muscle strength in older adults.
Specifically, when compared to the low-functioning older adult group, the researchers found higher levels of Prevotellaceae, Prevotella, Barnesiella, and Barnesiella intestinihominis—all potentially good bacteria—in the high-functioning older adults and in the mice that were colonized with fecal samples from the high-functioning older adults.