Effect of diet on splenic CD4⁺ T cell polarization.

<p>Splenic CD4⁺ cells were purified by positive selection and cultured for 3 d under A) Th17 or B) Treg polarizing conditions (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0049739#s2" target="_blank">Materials and Methods</a>, n = 3−4 TNBS treated mice/dietary group). Bars represent mean values ± SEM. Bars not sharing a common letter are significantly different (P≤0.05).</p

Visceral adipose tissue macrophage infiltration.

<p>Stromal vascular cells (SVC) were isolated and quantified from total visceral adipose tissue (HF and HF-FO groups, n = 3 vehicle controls and 6–8 TNBS-treated mice, LF n = 4 pooled samples comprised of 3–4 mice/treatment). A) percentage of F4/80⁺ CD11b⁺ cells (total macrophages), B) percentage of F4/80⁺ CD11c⁺ cells (M1 macrophages), C) percentage of F4/80⁺ CD206⁺ cells (M2 macrophages). Data were analyzed by two-way ANOVA (main effects: diet and treatment) and bars represent mean values ± SEM. Bars not sharing a common letter are significantly different (<i>P</i>≤0.05).</p

Visceral adipose tissue mRNA expression¹.

1<p>Values are means ± SEM (n = 5−10/dietary group). Data were analyzed by two-way ANOVA (main effects: diet and treatment). For all genes, there was no effect of treatment (i.e., TNBS versus vehicle, <i>P</i>>0.05), therefore, only the main effect of diet is shown. Within individual genes, values not sharing a lower case letter denote significant differences (<i>P</i>≤0.05). Data were normalized to ribosomal 18S.</p

Colon histological disease scores for TNBS-treated mice.

<p>Colonic mucosal injury (0–3) and inflammation (0–3) scores were assessed in a blinded manner by a board-certified pathologist (B. Weeks) and combined for a total score (0–6). Representative images (100 × magnification) are shown for the HF, HF-FO and LF TNBS-treated groups, respectively (panels A-C) and a representative image of a HF vehicle control (panel D) is shown. E) Combined injury/inflammation histological score within the distal colon (n = 10−14 TNBS treated mice/diet). Data were analyzed using the Kruskal-Wallis test followed by Wilcoxon two-sample testing, and bars represent median values. Bars not sharing a common letter are significantly different (P≤0.05).</p

Effect of diet and colitis on splenic T cell subsets.

<p>A) Tregs (CD4⁺ FOXP3⁺), B) Th17 (CD4⁺ IL17A⁺), and C) Th1 (CD4⁺ IFNγ⁺) cell populations (n = 3–6 vehicle controls and n = 6−12 TNBS treated mice/dietary group). Bars represent mean values ± SEM. Bars not sharing a common letter are significantly different (P≤0.05).</p

Characterization of the diet-induced obese phenotype.

<p>C57BL/6 mice were fed a high diet (HF), high fat diet supplemented with FO (HF-FO) or a low fat (LF) control diet for 12 weeks (n = 12−17 TNBS-treated and 4–6 vehicle controls/diet). Mice were presensitized with 1% TNBS or vehicle control (week 11), followed by a 2.5% TNBS enema or vehicle control (week 12) and sacrificed 3 d post-TNBS. A) Changes in body weight over time. B) Visceral adipose tissue weight from individual visceral depots (perinephric, mesenteric and epididymal) or combined (total visceral adipose). Serum concentrations of C) insulin, D) leptin, E) resistin and F) adiponectin. All data were analyzed by two-way ANOVA (main effects: diet and treatment) and <i>P</i>-values are shown. Bars represent means ± SEM and statistical significance was (<i>P</i>≤0.05). Panel A) asterisk (*) indicates statistically significant time points where the HF and HF-FO groups differed from LF (<i>P</i>≤0.05). Panels B-F) bars not sharing a common letter differ (<i>P</i>≤0.05).</p