Journal: Antioxidants

Article Title: DUOX2-Driven Oxidative Stress Alters the Gut Redox Niche and Promotes Microbial Dysbiosis in Crohn’s Disease

doi: 10.3390/antiox15030292

Figure Lengend Snippet: Parabacteroides enrichment in Duox2 knockout mouse intestines alleviates DSS-colitis: ( A – C ) 16S rRNA sequencing was conducted on fecal bacterial DNA isolated from healthy Duox2 KO and WT mice ( n = 4 mice/group). ( A ) Alpha diversity profiles (Chao1 and Shannon indices). ( B ) PCoA of beta diversity based on Bray–Curtis dissimilarity. ( C ) LEfSe bar plot displaying genus-level taxonomic variations between Duox2 KO and WT mice. Bacterial taxa with differential abundance were defined by an LDA score > 2. Blue bars represent genera enriched in WT mice, while pink bars indicate genera overrepresented in D uox2 KO mice. ( D ) Metagenomic sequencing was performed on fecal bacterial DNA from healthy WT and Duox2 KO mice ( n = 5 mice/group). LEfSe bar plot illustrates genus-level taxonomic differences between the two groups (LDA > 2). Blue bars denote genera enriched in WT mice, and pink bars indicate genera overrepresented in Duox2 KO mice. ( E ) qPCR was used to quantify the abundance of major Parabacteroides species in WT and Duox2 KO mice ( n = 10 mice/group). ( F – I ) Parabacteroides administration alleviated DSS-induced colitis. ( F ) Schematic of the P. distasonis intervention experiment. C57BL/6 WT mice received intragastric administration of an antibiotic cocktail for 14 days to deplete their gut microbiota. Three days prior to DSS exposure, mice were gavaged with either P. distasonis strain ATCC BAA-1295 (PD1; 1.0 × 10 9 CFUs/200 μL sterile PBS per mouse), P. distasonis strain ATCC 8503 (PD2; 1.0 × 10 9 CFUs per mouse), non-pathogenic Escherichia coli strain MG1655 (EC; 1.0 × 10 9 CFUs per mouse, bacterial control), or sterile PBS. Following DSS administration, gavage was continued every other day. ( G ) Body weight changes in the PD1, PD2, EC, and PBS groups ( n = 5 mice/group). ( H ) Colon length measurements across the four groups ( n = 5 mice/group). ( I ) Serum FD4 concentrations in the four groups. Data are presented as the mean ± SEM. Statistical analyses were performed using ordinary one-way ANOVA or the Kruskal–Wallis test, depending on data distribution. Note: ** p < 0.01, *** p < 0.001, **** p < 0.0001, ns: not significant.

Article Snippet: To functionally test whether P. distasonis mediates the protective phenotype, antibiotic-pretreated WT mice were orally gavaged once daily with P. distasonis strain ATCC BAA-1295 (PD1; 1.0 × 10 9 CFUs per mouse), P. distasonis strain ATCC 8503 (PD2; 1.0 × 10 9 CFUs per mouse), non-pathogenic E. coli strain MG1655 (EC; 1.0 × 10 9 CFUs per mouse, serving as a bacterial control), or PBS for 3 days before DSS administration ( F).

Techniques: Knock-Out, Sequencing, Isolation, Sterility, Control

Journal: Antioxidants

Article Title: DUOX2-Driven Oxidative Stress Alters the Gut Redox Niche and Promotes Microbial Dysbiosis in Crohn’s Disease

doi: 10.3390/antiox15030292

Figure Lengend Snippet: DUOX2-dependent oxidative stress restricts Parabacteroides proliferation: ( A ) Functional profiling of OS based on gut metagenomic data from Duox2 KO and WT mice. ( B ) Correlation analysis between differential bacterial genera and OS profiling in Duox2 KO and WT mice. Color key: Spearman’s correlation coefficient (Rho). Red gradients indicate positive correlations, purple gradients indicate negative correlations, and white indicates no correlation. ( C ) Relative growth of P. distasonis strains and E. coli under different hydrogen peroxide (H 2 O 2 ) concentrations. ( D ) Scanning electron microscopy (SEM) images showing morphological changes in P. distasonis and E. coli under different H 2 O 2 concentrations. ( E ) Representative immunofluorescence images showing ROS levels in P. distasonis and E. coli under different H 2 O 2 concentrations. ( F – H ) Proteomics sequencing analysis of P. distasonis and E. coli , with three biological replicates for each strain. ( F ) PCA of P. distasonis and E. coli , presenting the first and second principal components. ( G ) Volcano plot depicting the identified proteins in the two species. The significantly differentially abundant proteins are shown as blue dots and red dots, representing downregulated and upregulated proteins, respectively. The nonsignificant proteins are shown in gray. The screening criteria were p < 0.05 and |FC| ≥ 2. ( H ) Gene Ontology pathway analysis of differentially expressed proteins at the molecular function (MF) level ( p < 0.05). Exact p levels were all provided. PD1, P. distasonis strain ATCC BAA-1295; PD2, P. distasonis strain ATCC 8503; EC, E. coli MG1655. Note: * p < 0.05, ** p < 0.01, *** p < 0.001, ns: not significant.

Article Snippet: To functionally test whether P. distasonis mediates the protective phenotype, antibiotic-pretreated WT mice were orally gavaged once daily with P. distasonis strain ATCC BAA-1295 (PD1; 1.0 × 10 9 CFUs per mouse), P. distasonis strain ATCC 8503 (PD2; 1.0 × 10 9 CFUs per mouse), non-pathogenic E. coli strain MG1655 (EC; 1.0 × 10 9 CFUs per mouse, serving as a bacterial control), or PBS for 3 days before DSS administration ( F).

Techniques: Functional Assay, Electron Microscopy, Immunofluorescence, Sequencing