Related Experiment Video For BILE ACID
Updated: Mar 25, 2026
Injections of Lipopolysaccharide into Mice to Mimic Entrance of Microbial-derived Products After Intestinal Barrier Breach
Published on: May 2, 2018
Dysbiotic microbiota trigger colitis-associated colorectal cancer and imprint a distinctive bile acid profile in a
Muyiwa Awoniyi1,2,3,4, Mohamed El Hag5, Josue Hernandez3
1Center for Gastrointestinal Biology and Disease, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA muyiwa7@gmail.com.
Background:
Primary sclerosing cholangitis-associated UC (PSC-UC) carries excess colorectal neoplasia despite often mild-appearing endoscopy, implicating persistent microscopic inflammation and microbiota-bile acid (BA) dysfunction.
Objective:
To test whether PSC-UC neoplasia is driven by transferable microbiota-mediated inflammation linked to secondary BA loss.
Design:
Surveillance colonoscopies (2012-2022) from PSC-UC (n=251) and UC-only (n=8839) were compared for segmental endoscopic/histological activity and dysplasia. We generated multidrug resistance protein 2 (MDR2)-/- × interleukin (IL)-10-/- double-knockout (DKO) mice and used germ-free (GF) derivation, faecal microbiota transplantation (FMT), antibiotic conditioning and cohousing with shotgun metagenomics and liquid chromatography-tandem mass spectrometry BA profiling.
Results:
PSC-UC showed greater inflammatory activity and a right-shifted dysplasia burden versus UC-only. Under specific-pathogen-free conditions, DKO mice developed early right-predominant colitis and multifocal dysplasia progressing with age. DKO communities were depleted of 7α-dehydroxylation capacity with near absence of deoxycholic and lithocholic acids and no enrichment of canonical bacterial genotoxins. GF DKO mice were protected, whereas live DKO donor FMT reinstated severe colitis and dysplasia; sterile-filtered stool supernatant was inactive. IL-10-/- donor FMT or cohousing attenuated colitis and increased recipient secondary BA, whereas wild-type/MDR2-/- donor transfers were non-colitogenic. In GF DKO mice, direct deoxycholic acid repletion caused hepatotoxicity.
Conclusion:
PSC-UC neoplasia associates with transmissible microbiota-dependent inflammation and secondary BA deficiency. Controlled restoration of BA-transforming microbial functions, rather than indiscriminate secondary BA replacement, is a rational translational direction.
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