Fecal transplants rejuvenate immune system in the gut of aged mice

Fecal transplants from young to aged mice can stimulate the gut microbiome and revive the gut immune system, according to a new study by immunologists at the Babraham Institute in England and published in the journal Nature Communications.

Co-housing young and aged mice, or more directly performing fecal transfer from young to aged mice, boosted the gut immune system in the aged mice, partly correcting the age-related decline, the study said.

The gut is one of the organs that is most severely affected by aging and age-dependent changes to the human gut microbiome have been linked to increased frailty, inflammation, and increased susceptibility to intestinal disorders, researchers said. These age-dependent changes to the gut microbiome happen in parallel with a decrease in function of the gut immune system but it was previously unknown whether the two changes were linked.

The results show that the poor gut immune response is not irreversible and that the response can be strengthened by challenging with appropriate stimuli, essentially turning back the clock on the gut immune system to more closely resemble the situation in a young mouse, according to the study abstract.

Additionally, the results of the study have relevance for treating age-related symptoms, confirming a link between the effects of the aging immune system and age-associated changes in the gut microbiome. By demonstrating the effectiveness of interventions that have a positive impact on the composition of the gut microbiome, this research suggests that fecal transplants, probiotics, co-habitation, and diet might all prove to be ways to facilitate healthy aging.