Fig. 2. Effect of tanshinone I on expression and/or phosphorylation of C/EBP-α, PPAR-γ, and STAT-3/5 in differentiating 3T3-L1 cells. (A-C) 3T3-L1 preadipocytes were induced to differentiate with induction medium in the absence (vehicle control, 0.1%) or presence of tanshinone I, and harvested at day 2, 5, and 8, respectively. Cellular protein and mRNA at the indicated time point were extracted and analyzed by Western blot (A, C) and RT-PCR (B) analysis, respectively. (D-F) Western blot (D,F) and RT-PCR (E) analysis in triplicate experiments on day 8, respectively. (G) and (H) are the densitometry data of (D) and (E), respectively. (I) is the densitometry result of (F). C/EBP-α: CCAAT/enhancer-binding protein-α, PPAR-γ: peroxisome proliferator-activated receptor-γ, STAT: signal transducer and activator of transcription, MDI: 0.5 mM IBMX, 0.5 μM dexamethasone, and 5 μg/mL insulin, FBS: fetal bovine serum, Tan I: tanshinone I, mRNA: messenger RNA, RT-PCR: reverse transcription polymerase chain reaction. *P<0.05 compared to the value of tanshinone I free control at the indicated day.
