Figure 2: Effect of rosiglitazone on MMP-1 and collagen I in lung fibroblasts. (a) MMP-1 activity in lung fibroblasts. Each bar represents the mean and SD of duplicate determinations in 4 independent experiments. (b) Effect of rosiglitazone on collagen type I in white normal (1), white scleroderma (2), black normal (3), and black scleroderma (4) lung fibroblasts. (c) PPARγ antagonist GW inhibits effect of rosiglitazone on collagen in white scleroderma fibroblasts. Immunoblots in (b) and (c) are representative of 5 independent experiments. The results of immunoblot analysis were quantified. Values are the mean and SD of densitometry units corresponding to the α1 and α2 chains of type I collagen. * versus unstimulated cells.