Fig. 5: ATF3 mediates the inhibitory effect of STAT5 on adipocyte differentiation.

a–c BMSCs were isolated from femurs and tibias of Stat5 cKO mice and their wild-type littermates followed by transduction with control (pMX-IRES-EGFP) or ATF3 (pMX-ATF3-IRES-EGFP) retroviral vectors and were then cultured in the presence or absence of adipogenic differentiation factors (insulin, rosiglitazone, dexamethasone, and IBMX) for 5 days. a Cultured cells were stained using Oil Red O solution. b The number of Oil Red O-positive adipocytes was quantified. ***P < 0.001 vs. control; n.s. not significant. Statistical analyses were performed via ANOVA. c The mRNA levels of Pparɣ, Cebpα, Fabp4, Stat5a, and Atf3 were assessed by quantitative real-time PCR. The data are presented as the mean ± SD of triplicate samples. **P < 0.01; ***P < 0.001 vs. control; n.s. not significant. Statistical analyses were performed via ANOVA. d–f BMSCs were isolated from femurs and tibias of wild-type mice followed by transfection with negative control siRNA (NC) or Atf3 siRNA (siAtf3) after transduction with control (pMX-IRES-EGFP) or constitutively active STAT5A (pMX-STAT5A1*6-IRES-EGFP) retroviral vectors. Cells were cultured in the presence or absence of adipogenic differentiation factors (insulin, rosiglitazone, dexamethasone, and IBMX) for 5 days. d Cultured cells were stained using Oil Red O solution. e The number of Oil Red O-positive adipocytes was quantified. **P < 0.01 vs. control; n.s. not significant. Statistical analyses were performed via ANOVA. f The mRNA levels of Pparɣ, Cebpα, Fabp4, Stat5a, and Atf3 were assessed by quantitative real-time PCR. The data are presented as the mean ± SD of triplicate samples. *P < 0.05; ***P < 0.001 vs. control; n.s. not significant. Statistical analyses were performed via ANOVA. AGM Adipogenic differentiation medium. Bars: (a) 200 µm; (d) 200 µm.