Fig. 6. Rosiglitazone protects dFBs from TGFβ and increases resistance of mice to SA infection.

(A and B) Primary neonatal dFBs were pretreated with or without rosiglitazone (ROSI; 20 µM), followed by treatment with or without TGFβ2 (0.1 ng/ml) and then subjected to adipocyte differentiation. (A) Representative phase-contrast images showing adipocyte formation (n = 3 per group). (B) qRT-PCR analyses of Pparg2, Camp, Adipoq, and Fabp4 as indicated (n = 3 per group). (C and D) Primary neonatal dFBs were treated with ROSI with or without SB431542 (SB; TGFBR inhibitor) and then subjected to adipocyte differentiation conditions. (C) Representative phase contrast images showing adipocyte formation (n = 3 per group). (D and E) Heatmap showing relative mRNA expression (quantified by qRT-PCR) of selected fibrotic genes in undifferentiated cells and selected adipocyte genes in day 1 differentiated cells. (F and G) Neonatal dFB cocultured with AD with or without SB or ROSI as indicated. (F) Representative phase images showing adipocyte formation (n = 3 per group). (G) qRT-PCR analyses of selected fibrotic genes or adipocyte genes (n = 3 per group). (H to J) SD or HFD mice were treated with SB or ROSI then infected intradermally with S. aureus. (H) Measurement of bacterial CFU from the infection edge area of the skin (n = 5 to 6 per group). (I and J) Skin sections were stained with pC/EBPβ (red) and COLIV (green) as shown in (I) or CAMP (red) and COLIV (green) as shown in (J). Nuclei were stained by DAPI (blue). Scale bars (A, C, F, I, and J), 100 µm. (K) Conditional heterozygous Tgfbr2 deletion in Pdgfra⁺ fibroblasts, Tgfbr2^flox/+;Pdgfra-cre = Tgfbr2^Pd−/+, was achieved through the breeding of Tgfbr2^flox/flox mice with Pdgfra-cre mice. (L to M) WT (Tgfbr2^flox/flox) or Tgfbr2^Pd−/+ mice were infected intradermally with S. aureus. (L) Effect of heterozygous deletion of Tgfbr2 in Pdgfra⁺ dFBs on resistance of obese HFD mice to S. aureus intradermal infection as shown by measurement of bacterial CFU count in infected skin sites (n = 5 to 8 per group). (M) S. aureus killing activity of whole mouse blood (n = 5 per group). All error bars indicate mean ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001 (one-way ANOVA).