Effects of metformin on MMP activity. Enhanced MMP activities were seen in intimal SMCs treated with MG or fructose in vitro (Figure 3A). Treatment with metformin significantly inhibited the enzyme activity as observed through the relatively faint band and the reduced intensity of the bands quantified by NIH image. Figures 3B and C indicate the relative density of MMP2 and MMP, respectively. MG + or Fructose + in Figures 3B and C means co-treatment with metformin.