Fig 2. Activation of canonical Wnt signaling in FSP1⁺ fibroblasts disturbs adipose homeostasis.

(A) Western blot analyses of β-catenin expression in adipocytes (left panels) and SVF cells (right panels) isolated from WAT from F-BCA compound mice and their littermates with WT, Fsp1-Cre, or Ctnnb1^{exon 3 fl/+} genotypes (Ctrl). TTFs were used as a positive Ctrl for activated form β-catenin expression. (B) Body weight of male F-BCA mice and their littermates on ND. n = 9 for male Ctrl mice, and n = 10 for male F-BCA mice. (C) Ventral view of subcutaneous and visceral adipose depots of male Ctrl and F-BCA littermates on ND at 4 months of age. Adipose depots are circled with dashed lines. (D) Percent body fat (NMR spectroscopy) of Ctrl and F-BCA littermates on ND at 4 months of age. n = 6 for male Ctrl and F-BCA mice. (E, F) Representative pictures and weight of the adipose tissues of F-BCA mice and their littermates on ND at 4 months of age. n = 8 for male Ctrl mice, and n = 14 for male F-BCA mice. (G) HE staining of WAT sections of 4-month-old F-BCA mice and their littermates on ND. Scale bar: 200 μm. (H) GTT of F-BCA mice and their littermates on ND at 4 months of age. n = 13 for male Ctrl mice, and n = 5 for male F-BCA mice. (I) Quantification of the AUC of the GTT relative to Ctrl group. (J) ITT of F-BCA mice and their littermates on ND at 4 months of age. n = 10 for male Ctrl mice, and n = 5 for male F-BCA mice. (K) Quantification of the AUC of the ITT relative to Ctrl group. Data are presented as mean ± SEM. Statistical analyses were performed with two-tailed unpaired student t test (panel D, F, I, and K) or two-way ANOVA followed by Bonferroni's multiple comparison test (panel B, H, and J). *p < 0.05; **p < 0.01; ***p < 0.001. Underlying data can be found in S1 Data. AUC, area under the curve; Ctrl, control; F-BCA, Fsp1-Cre;Ctnnb1^{exon 3 fl/+}; FSP1, fibroblast-specific protein-1; GTT, glucose tolerance test; HE, hematoxylin–eosin; ITT, insulin tolerance test; ND, normal-chow diet; NMR, nuclear magnetic resonance; NS, not significant; SVF, stromal vascular fraction; TTF, tail tip fibroblast; WAT, white adipose tissue; WT, wild-type.