Figure 2.

Inhibition of adipogenesis by rosmarinic acid (RA) via the activation of extracellular signal-regulated kinase-1/2 (ERK1/2) and mothers against decapentaplegic homolog 3 (Smad3). (A) Protein expression of phosphorylated (p-)ERK1/2 and Smad3 after RA (50 μM, 12 h) incubation on day 6 of differentiation. (B) Oil Red O staining of the 3T3-L1 adipocytes (on day 6 post-differentiation) treated with RA in the absence or presence of PD98059 (PD, 25 μM) and SB431542 (SB, 2 μM) for 24 h. (C) Protein expression of p-ERK1/2 and Smad3 after RA (50 μM, 12 h) incubation in the presence or absence of PD98059 (25 μM) and SB431542 (2 μM) for 24 h. Representative blots are shown to the right of the graphs. Data are presented as means ± SEM in (A) and (C). All cell culture experiments were repeated at least three times on two separate passages of cells (n = 6). *p < 0.05 vs vehicle (Veh) group.