Journal: Advanced Science

Article Title: Secondary Bile Acids Modified by Odoribacter Splanchnicus Alleviate Colitis by Suppressing Neutrophil Extracellular Trap Formation

doi: 10.1002/advs.202509073

Figure Lengend Snippet: O. splanchnicus promotes LCA transformation via gut microbiota. A) Experimental design for in vitro culture of O. splanchnicus . O. splanchnicus (OD = 0.1) was supplemented with CA, CDCA, LCA, and UDCA. The conditioned medium was analyzed for the concentration of bile acid. B) Concentrations of LCA, C) alloLCA, and D) 12‐ketoLCA. Data are shown as mean ± SEM. **** , P < 0.0001, as determined by the nonparametric Kruskal–Wallis’ test. E) Experimental design for germ‐free mice treated with O. splanchnicus . Each mouse was gavaged daily with O. splanchnicus at a concentration of 10 8 CFU/200 µL for 2 weeks. In the final week of the experiment, 2% DSS was added to the drinking water. O. splanchnicus was suspended in sterile PBS, and an equivalent volume of sterile PBS was used as a vehicle control. F) Concentrations of LCA and its derivatives in the feces of germ‐free mice. Data are shown as mean ± SEM. ** , P < 0.01; *** , P < 0.001; **** , P < 0.0001, as determined by unpaired Student's t test. G) Relative abundance of BSH‐containing genera in DSS‐induced colitis mice following O. splanchnicus intervention. H) Relative abundance of HSDH‐containing genera in DSS‐induced colitis mice following O. splanchnicus intervention. I) Experimental design for 3% DSS‐induced colitis mice receiving FMT. Mice were pretreated with Abx for 4 weeks to deplete most bacteria in the gut. Donor mice received O. splanchnicus ‐containing stool via oral gavage, while also being treated with 3% DSS in drinking water. Weight loss, DAI, and colon length were monitored. Distal colon tissue was collected for HE staining, and the remaining colon was reserved for further validation. J) Weight loss, K) DAI scores, L) representative images of the colon, and statistical analysis of colon length. Data are shown as mean ± SEM. * , P < 0.05; ** , P < 0.01; *** , P < 0.001, as determined by unpaired Student's t test. M) Representative images of HE staining at 20× and 40× magnification, with comparison of statistical histological scores across groups. Data are shown as mean ± SEM. **** , P < 0.0001, as determined by unpaired Student's t test. N) Representative images of IF staining for Zo‐1 (green), Occludin (green), Claudin1 (green), and Muc2 (green) in colitis mice. O) Experimental design for 3% DSS‐induced colitis mice receiving Abx pretreatment. Ampicillin (1 g L −1 ), neomycin (1 g L −1 ), metronidazole (1 g/L), and vancomycin (0.5 g/L) were added to the drinking water of mice ad libitum for 4 weeks to eliminate most gut bacteria. Subsequently, O. splanchnicus was administered via oral gavage, and 3% DSS was added to the drinking water for 7 days. P) Weight loss, (Q) DAI scores, (R) representative images of the colon, and statistical analysis of colon length. Data are shown as mean ± SEM. “ns” indicates no significant difference, as determined by unpaired Student's t test. S) Representative images of HE staining at 20× and 40× magnification, with comparison of statistical histological scores across groups. T) Representative images of IF staining for Zo‐1 (green), Occludin (green), Claudin1 (green), and Muc2 (green) in colitis mice with Abx pretreatment.

Article Snippet: The logarithmic growth stage of O. splanchnicus (OD = 0.1) was inoculated into a medium containing bile acid substrates: CDCA (HY‐76847, MCE), CA (HY‐N0324, MCE), LCA (L6250, Sigma), and UDCA (HY‐13771, MCE).

Techniques: Transformation Assay, In Vitro, Concentration Assay, Sterility, Control, Bacteria, Staining, Biomarker Discovery, Comparison