Figure 1.

Effects of andrographolide on cell proliferation in vascular smooth muscle cells (VSMCs) stimulated by platelet-derived growth factor-BB (PDGF-BB). (A) VSMCs (2 × 10⁴ cells/well) were treated with PBS (resting) or pretreated with andro (20 and 50 mM), or an isovolumetric solvent control (0.1% DMSO), followed by the addition of PDGF-BB (10 ng/ml). Cell numbers were evaluated by an MTT assay as described under Materials and Methods. (B) VSMCs (2 × 105 cells/dish) were treated with PBS (resting) or pretreated with solvent control (0.1% DMSO) or 20-100 μM andro, followed by the addition of PDGF-BB (10 ng/ml). Compiled statistical data are shown on the right. * p < 0.01 compared to the resting (PBS treatment) group; ^# p < 0.01; ^† p < 0.001, compared to the PDGF-BB group. Data are presented as the mean ± SEM (N = 5).