The function of Bacteroides intestinalis DSM 17393 in the mouse colon and its potential application as a probiotic

Accumulating evidence suggests that consumption of wheat arabinoxylan (hereinafter referred to as WAX) has many beneficial effects to the host, such as strengthening the immune system, lowering inflammation, and reducing colon cancer disease risk. WAX is a complex indigestible and insoluble dietary fiber that can be found in the outer layer of the wheat kernel, also known as wheat bran. WAX can modulate microbiota metabolic function by acting as a source of prebiotic in the colon that can be metabolized by the gut microbiota into various WAX-derived bioactive metabolites. However, how WAX-derived microbial metabolites can protect the host from inflammation remains incompletely understood. Bacteroides spp. are the predominant human gut commensals. Several Bacteroides species are known to metabolize complex arabinoxylans in vitro into numerous characterized and uncharacterized metabolites. Recently, a human colonic commensal Bacteroides intestinalis DSM 17393 (hereinafter referred to as BI), a member of the genus Bacteroides, has been reported to metabolize WAX in vitro into numerous well established anti-inflammatory metabolites, including but not limited to short chain fatty acids and ferulic acid. Thus, I hypothesize that BI can metabolize WAX into various anti-inflammatory metabolites in vivo to mitigate host inflammation. The objectives of the projects represented in this thesis are (1) to investigate the normal physiological function of BI in the mouse colon, (2) to identify alterations to host metabolome due to BI fermentation of WAX, and (3) to investigate whether BI can metabolize WAX in vivo into various anti-inflammatory metabolites to mitigate host inflammation. The results of this study demonstrate that BI could modulate host colonic goblet cells to enhance mucus secretion, indicating a crucial role of BI in enhancing the colonic mucus barrier. Importantly, WAX-derived BI metabolites could mitigate inflammation in a mouse model of chemical-induced colitis. Future studies are needed to identify and characterize which WAX-derived BI metabolites can mitigate inflammation. With this newfound knowledge, BI will have potential application as a probiotic that is amenable to WAX supplementation for the treatment of colitis.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

VMS - Comparative Biosciences

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2024

Author dc:creator

• Nguyen, William

Contributors dc:contributor

• Mei, Wenyan
• Yang, Jing
• Wang, Bo
• Lau, Gee
• Gaulke, Christopher

• Arabinoxylan
• Bacteroides Intestinalis
• Probiotics
• Mucus
• Goblet Cells
• Metabolites
• Fermentation
• Inflammation

Statement dc:rights

• Copyright © 2024 Ka Lam Nguyen. All rights reserved.

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/124630

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F124630