Background The use of Akkermansia muciniphila as potential therapeutic intervention is receiving increasing attention. Health benefits attributed to this bacterium include an improvement of metabolic disorders and exerting anti-inflammatory effects. The abundance of A. muciniphila is associated with a healthy gut in early mid- and later life. However, the effects of A. muciniphila on a decline in intestinal health during the aging process are not investigated yet. We supplemented accelerated aging Ercc1−/Δ7 mice with A. muciniphila for 10 weeks and investigated histological, transcriptional and immunological aspects of intestinal health. Results The thickness of the colonic mucus layer increased about 3-fold after long-term A. muciniphila supplementation and was even significantly thicker compared to mice supplemented with Lactobacillus plantarum WCFS1. Colonic gene expression profiles pointed towards a decreased expression of genes and pathways related to inflammation and immune function, and suggested a decreased presence of B cells in colon. Total B cell frequencies in spleen and mesenteric lymph nodes were not altered after A. muciniphila supplementation. Mature and immature B cell frequencies in bone marrow were increased, whereas B cell precursors were unaffected. These findings implicate that B cell migration rather than production was affected by A. muciniphila supplementation. Gene expression profiles in ileum pointed toward a decrease in metabolic- and immune-related processes and antimicrobial peptide production after A. muciniphila supplementation. Besides, A. muciniphila decreased the frequency of activated CD80+CD273− B cells in Peyer’s patches. Additionally, the increased numbers of peritoneal resident macrophages and a decrease in Ly6Cint monocyte frequencies in spleen and mesenteric lymph nodes add evidence for the potentially anti-inflammatory properties of A. muciniphila. Conclusions Altogether, we show that supplementation with A. muciniphila prevented the age-related decline in thickness of the colonic mucus layer and attenuated inflammation and immune-related processes at old age. This study implies that A. muciniphila supplementation can contribute to a promotion of healthy aging.

doi.org/10.1186/s12979-019-0145-z, hdl.handle.net/1765/116139
Immunity and Ageing
Department of Immunology

van der Lugt, B., van Beek, A.A., Aalvink, S., Meijer, B, Sovran, B., Vermeij, W.P., … Belzer, C. (2019). Akkermansia muciniphila ameliorates the age-related decline in colonic mucus thickness and attenuates immune activation in accelerated aging Ercc1(-/7) mice. Immunity and Ageing, 16. doi:10.1186/s12979-019-0145-z