Bacteroides ovatus Colonization Influences the Abundance of Intestinal Short Chain Fatty Acids and Neurotransmitters

Authors

Thomas D Horvath
Faith D Ihekweazu
Sigmund J Haidacher
Wenly Ruan
Kristen A Engevik
Robert Fultz
Kathleen M Hoch
Ruth Ann Luna
Numan Oezguen
Jennifer K Spinler
Anthony M Haag
James Versalovic
Melinda A Engevik

Publication Date

5-20-2022

Journal

iScience

DOI

10.1016/j.isci.2022.104158

PMID

35494230

PMCID

PMC9038548

PubMedCentral® Posted Date

3-25-2022

PubMedCentral® Full Text Version

Post-print

Published Open-Access

yes

Keywords

Neuroscience, Microbiology, Microbiome

Abstract

Gut microbes can synthesize multiple neuro-active metabolites. We profiled neuro-active compounds produced by the gut commensal Bacteroides ovatus in vitro and in vivo by LC-MS/MS. We found that B. ovatus generates acetic acid, propionic acid, isobutyric acid, and isovaleric acid. In vitro, B. ovatus consumed tryptophan and glutamate and synthesized the neuro-active compounds glutamine and GABA. Consistent with our LC-MS/MS-based in vitro data, we observed elevated levels of acetic acid, propionic acid, isobutyric acid, and isovaleric acid in the intestines of B. ovatus mono-associated mice compared with germ-free controls. B. ovatus mono-association also increased the concentrations of intestinal GABA and decreased the concentrations of tryptophan and glutamine compared with germ-free controls. Computational network analysis revealed unique links between SCFAs, neuro-active compounds, and colonization status. These results highlight connections between microbial colonization and intestinal neurotransmitter concentrations, suggesting that B. ovatus selectively influences the presence of intestinal neurotransmitters.