The gut commensal Blautia maintains colonic mucus function under low fiber consumption through short-chain fatty acid-mediated activation of Ffar2

Holmberg, S. M.; Feeney, R. H.; Prasoodanan P.K., V.; Puertolas-Balint, F.; Singh, D. K.; Wongkuna, S.; Zandbergen, L. M.; Hauner, H.; Brandl, B.; Nieminen, A. I.; Skurk, T.; Schroeder, B. O.

doi:10.1101/2023.12.10.570766

bioRxiv · 10.1101/2023.12.10.570766

The gut commensal Blautia maintains colonic mucus function under low fiber consumption through short-chain fatty acid-mediated activation of Ffar2

Holmberg, S. M.·Feeney, R. H.·Prasoodanan P.K., V.·Puertolas-Balint, F.·Singh, D. K.·Wongkuna, S.·Zandbergen, L. M.·Hauner, H.·Brandl, B.·Nieminen, A. I.·Skurk, T.·Schroeder, B. O.

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Abstract

Beneficial gut bacteria are indispensable for developing colonic mucus and fully establishing its protective function against intestinal microorganisms. Low-fiber diet consumption alters the gut bacterial configuration and disturbs this microbe-mucus interaction, but the specific bacteria and microbial metabolites responsible for maintaining mucus function remain poorly understood. By using human-to-mouse microbiota transplantation and ex vivo analysis of colonic mucus function, our proof-of-concept study demonstrates that individuals who increase their daily dietary fiber intake can improve the capacity of their gut microbiota to prevent diet-mediated mucus defects. Mucus growth, a critical feature of intact colonic mucus, correlated with the abundance of the gut commensal Blautia, and supplementation of Blautia coccoides to mice confirmed its mucus-stimulating capacity. Mechanistically, B. coccoides stimulated mucus growth through the production of the short-chain fatty acids propionate and acetate via activation of the short-chain fatty acid receptor Ffar2, which could serve as a new target to restore mucus growth during mucus-associated lifestyle diseases.

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Holmberg, S. M., Feeney, R. H., Prasoodanan P.K., V., Puertolas-Balint, F., Singh, D. K., Wongkuna, S., Zandbergen, L. M., Hauner, H., Brandl, B., Nieminen, A. I., Skurk, T., Schroeder, B. O.. 2023-12-10. The gut commensal Blautia maintains colonic mucus function under low fiber consumption through short-chain fatty acid-mediated activation of Ffar2. https://doi.org/10.1101/2023.12.10.570766

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