FIGURE 3.

High Fiber diet alters the gut microbial community structure and protects against FAN associated acute dysbiosis at day 2. Fecal DNA analysis using 16S rRNA sequencing was performed on mice fed a NC (FAN: n = 11; non-FAN: n = 4) and HF (FAN: n = 7; non-FAN: n = 5) diet at day 2 after FAN induction. (A) Principal coordinate analysis of the weighted Unifrac distances demonstrates significant modulation in the microbiota community with cluster separation between diet groups and mice with and without FAN. (B,C) Taxonomical composition and relative abundance of different bacteria by ANCOM analysis at the phylum level, depicting “dysbiosis” with expansion of Verrucomicrobia at the expense of Actinobacteria in NC fed mice, which was modulated by HF feeding. A HF diet suppressed the Firmicutes to Bacteroidetes ratio. (D) At the genus level, NC fed FAN mice had lower levels of the SCFA producers Bifidobacterium and Prevotella, with relative expansion of the pathobiont Odoribacter compared to those fed HF. (E) DESeq2 analysis demonstrating differential abundant OTUs (FDR adjusted P < 0.01) between dietary groups after FAN induction. OTUs were assigned to their lowest described classification (y-axis) and color coded by phylum. Bubble size represents a log fold change in the log base mean of the recorded OTU, with the x-axis values demonstrating log2 fold change in relative abundance. (F) Pearson-correlation-based heatmap at a genus level, identifying the bacteria associated with increment of serum urea and creatinine. Cool colors represent negative correlation and hot colors represent positive correlations. Data are shown as means ± SD; *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.