The relative proportions of various microbial species making up the gut microbiome changes with age, in ways that provoke greater chronic inflammation and reduce the generation of beneficial metabolites such as butyrate. This likely contributes to many different age-related diseases, but producing the data to firmly support that hypothesis remains a work in progress. Papers such as the one noted here are being published at a fair pace these days, building out an understanding of the correlation between specific changes in the gut microbiome and specific age-related conditions. Even as this body of knowledge is established, it already seems clear that interventions capable of restoring a more youthful gut microbiome must be brought to the clinic and widely deployed.
Sarcopenia is an age-related muscle disorder that increases risks of adverse clinical outcomes, but its treatments are still limited. Gut microbiota is potentially associated with sarcopenia, and its role is still unclear. To investigate the role of gut microbiota in sarcopenia, we first compared gut microbiota and metabolites composition in old participants with or without sarcopenia. Fecal microbiota transplantation (FMT) from human donors to antibiotic-treated recipient mice was then performed. Specific probiotics and their mechanisms to treat aged mice were identified.
Old people with sarcopenia had different microbial composition and metabolites, including Paraprevotella, Lachnospira, short-chain fatty acids, and purine. After FMT, mice receiving microbes from people with sarcopenia displayed lower muscle mass and strength compared with those receiving microbes from non-sarcopenic donors. Lacticaseibacillus rhamnosus (LR) and Faecalibacterium prausnitzii (FP) were positively related to muscle health of old people, and enhanced muscle mass and function of aged mice.
Transcriptomics showed that genes related to tricarboxylic acid cycle (TCA) were enriched after treatments. Metabolic analysis showed increased substrates of TCA cycle in both LR and FP supernatants. Muscle mitochondria density, ATP content, NAD+/NADH, mitochondrial dynamics and biogenesis proteins, as well as colon tight junction proteins of aged mice were improved by both probiotics. LR and the combination of two probiotics also benefit intestinal immune health by reducing CD8+ IFNγ+ T cells.
Link: https://doi.org/10.1111/acel.14485
View the full article at FightAging
