Intestinal Bacteroides Modulates Systemic Inflammation and the Microbial Ecology in a Mouse Model of CF: Evidence for Propionate and other Short Chain Fatty Acids Reducing Systemic Inflammatory Cytokines

Price, C.; Valls, R.; Ramsey, A.; Loeven, N.; Jones, J.; Barrack, K.; Schwartzman, J.; Royce, D.; Cramer, R. A.; Madan, J.; Ross, B.; Bliska, J. B.; O'Toole, G.

doi:10.1101/2022.01.05.475125

bioRxiv · 10.1101/2022.01.05.475125

Intestinal Bacteroides Modulates Systemic Inflammation and the Microbial Ecology in a Mouse Model of CF: Evidence for Propionate and other Short Chain Fatty Acids Reducing Systemic Inflammatory Cytokines

Price, C.·Valls, R.·Ramsey, A.·Loeven, N.·Jones, J.·Barrack, K.·Schwartzman, J.·Royce, D.·Cramer, R. A.·Madan, J.·Ross, B.·Bliska, J. B.·O'Toole, G.

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Abstract

Persons with cystic fibrosis, starting in early life, have intestinal microbiome dysbiosis characterized in part by a decreased relative abundance of the genus Bacteroides. Bacteroides is a major producer of the intestinal short chain fatty acid (SCFA) propionate. We demonstrate here that CFTR-/- Caco-2 intestinal epithelial cells are responsive to the anti-inflammatory effects of propionate. Furthermore, Bacteroides isolates inhibit the IL-1{beta}-induced inflammatory response of CFTR-/- Caco-2 intestinal epithelial cells and do so in a propionate-dependent manner. Bacteroides isolates also produce low levels of butyrate; this SCFA is positively correlated with inhibition of the inflammatory response. Finally, the introduction of Bacteroides-supplemented stool from infants with CF into the gut of CftrF508del mice results in an increase in propionate in the stool as well as the reduction in several systemic pro-inflammatory cytokines. Bacteroides supplementation also reduced the fecal relative abundance of E. coli, indicating a potential interaction between these two microbes, consistent with previous clinical studies. Together, our data indicate the important role of Bacteroides and Bacteroides-derived propionate in the context of the developing microbiome in infants and children with CF, which could help explain the observed gut-lung axis in CF.

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Price, C., Valls, R., Ramsey, A., Loeven, N., Jones, J., Barrack, K., Schwartzman, J., Royce, D., Cramer, R. A., Madan, J., Ross, B., Bliska, J. B., O'Toole, G.. 2022-01-05. Intestinal Bacteroides Modulates Systemic Inflammation and the Microbial Ecology in a Mouse Model of CF: Evidence for Propionate and other Short Chain Fatty Acids Reducing Systemic Inflammatory Cytokines. https://doi.org/10.1101/2022.01.05.475125

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