Figure 2
From: Metformin is a novel suppressor for transforming growth factor (TGF)-β1
Metformin attenuates TGF-β1 downstream signaling through AMPK independent pathway (a) AMPK inhibitor, Compound C (5 μM) were pretreated in 3T3 cells for 4 h. n = 5. (b) Negative control siRNA and AMPKα1/2 siRNA (80 nM) were transfected in 3T3 cells for 48 h. n = 6. Next, metformin and TGF-β1 (0.5 ng/mL) were premixed for 2 h and then the 3T3 cells were treated with the mixture for 30 minutes. Western blot analysis and quantification of phosphorylated-Smad2 (p-Smad2), Smad2, p-Smad3, Smad3, p-AMPK, AMPK, p-ACC, ACC and GAPDH were performed. Data are mean ± SEM. Kruskal–Wallis ANOVA combined with post-hoc Dunn’s multiple comparison test (two tailed) was performed. *P < 0.05 vs. TGF-β1 group, #P < 0.05 vs. TGF-β1 plus compound C or TGF-β1 plus AMPKα1/2 siRNA group.
