Fig. 4

Effect of PAH and oxy-PAH on MMPs expression and VSMCs migration. a The expression levels of MMP2 and MMP9 were analyzed by western blotting. Serum-starved VSMCs were treated with control (0.1% DMSO), PAHs or oxy-PAHs for 24 h. The band densities were normalized to β-actin band density. The gel images shown are representative of those obtained from at least three independent experiments. b The effect of NAC treatment on the expression levels of MMPs was quantified by western blot. Same volume of water was added in control group for NAC treatment. c The mRNA levels of MMPs in VSMCs following the treatment of NAC were quantified by qPCR. Gene expression was normalized to GAPDH. d The transcriptional activity of the MMPs promoter was evaluated using a luciferase assay in VSMCs with or without NAC or α-NF treatment. Same volume of DMSO was added in control group for α-NF treatment. Control values of NAC or α-NF were converted to 1 for comparing with the experimental values. e The effects of NAC or α-NF on VSMCs migration were evaluated using a wound healing assay. The wound healing area was measured using ImageJ software. The images from the wound healing assay are representative of five independent experiments, taken at the time of scratching and 48 h after scratching. The black line represents the initial boundaries following the scratch at time 0, and the white dotted line represents the migrating cell front after 48 h. All values are represented as mean ± SD. *P < 0.05 and ***P < 0.001 versus control; ^#P < 0.05 oxy-PAH versus PAH; ^$P < 0.05, ^$$P < 0.01, and ^$$$P < 0.001 PAHs with NAC versus PAHs alone; ^&P < 0.05, ^&&P < 0.01, and ^&&&P < 0.001 PAHs with α-NF versus PAHs alone; NS, no significance