Figure 2.

DBT and adipogenesis in human and mouse MSCs. Adipogenic differentiation was induced in (A, B) human and (C, D) mouse MSCs in the presence of adipogenic cocktail (MDI) and DBT ($1\text{nM}–100\text{nM}$); $500\text{nM}$ ROSI and $50\text{nM}$ TBT were used as positive controls and data were compared to 0.1% DMSO (vehicle). Media were replaced with fresh cocktail and ligands every 3 d for 14 d. (A, C) Graphs show lipid accumulation represented as the ratio between relative fluorescence units (RFU) of Nile Red and Hoechst. Hoechst is used to normalize lipid content to the number of cells per well. Each bar represents the average of 6 $\text{replicates}\pm \text{SEM}.$ (B, D). Gene expression is reported as fold induction over vehicle (0.1% DMSO) $\text{controls}\pm \text{SEM}.$ One-way analysis of variance (ANOVA) was conducted to compare DMSO and the different concentrations of DBT, followed by Dunnett’s post-hoc test. Unpaired t-test was conducted for the positive controls ROSI and TBT versus vehicle. Note: $\mathrm{C}/\text{EBP}\mathrm{\alpha }$, CCAAT/Enhancer Binding Protein Alpha; DBT, dibutyltin; DMSO, dimethylsulfoxide; Fabp4, fatty acid binding protein-4; Fsp27, fat-specific protein-27; LPL: lipoprotein lipase; h/mMSCs, human/mouse mesenchymal stem cells; $\text{PPAR}\mathrm{\gamma }2$, peroxisome proliferator–activated receptor gamma; ROSI, rosiglitazone; SEM, standard error of the mean; TBT, tributyltin. *$p\le 0.05$ in comparison with vehicle.