Figure 11.

Genetic depletion of TLR signaling adaptor MyD88 phenocopies microbiota ablation in response to WSD. Conventionally raised 3- to 5-week-old male C57BL/6J, wild-type and MyD88 KO mice were purchased from The Jackson Laboratory. Animals were placed on a high-fat diet (60% kcal from fat) for 8 weeks or continued on a standard grain-based chow as a control. At day 56, mice were killed for tissue collection and biometric measurements, data from WSD-treated mice represented here are relative to the chow-fed mice of their corresponding groups, as follows: (A) final body weight; (B) epididymal adipose tissue weight; (C) 15-hour fasting blood glucose level; (D) ALT concentration, AST concentration, and total cholesterol; (E) colon weight/length ratio; and (F) spleen weight. Epididymal adipose tissue from the epididymitis of mice was analyzed using flow cytometry and quantitative reverse-transcription polymerase chain reaction to quantify the following: (G) macrophages, (H and I) M1 macrophages, (J and K) M2 macrophages, (L) M1:M2 ratio, (M) inflammatory cytokines, and (N) eosinophils. Colon tissue was used to quantify the following: (O) DCs, (P) CD103^- DCs, (Q) CD103⁺ DCs, and (R) neutrophils. Data are the means ± SD (N=5). Statistical significance was determined using 1-way analysis of variance corrected for multiple comparisons with a Bonferroni test. *P ≤ .05, **P ≤ .01, ***P ≤ .001, and ****P ≤ .0001. eAT, epididymal adipose tissue; mRNA, messenger RNA; ns, nonsignificant.