Figure 3.

Effects of hydroxymethylglutaryl-coenzyme A (HMG-CoA) downstream intermediates on simvastatin-mediated inhibition of transforming growth factor-β (TGF-β)-induced RhoA, Rho-associated protein kinase 1 (ROCK1), and α-smooth muscle actin (α-SMA) expression. (A) Graves’ ophthalmopathy (GO) orbital fibroblasts were stimulated with TGF-β1 (3 ng/mL) for 48 h with or without a 1-h pretreatment with simvastatin (10 μM) and addition of geranylgeranyl pyrophosphate (GGPP) (10 μM), farnesyl pyrophosphate (FPP) (10 μM), or mevalonate (200 μM). The protein levels of RhoA, ROCK1, and α-SMA were determined using western blot analysis. (B–D) The densities of RhoA (B), ROCK1 (C), and α-SMA (D) protein bands were quantified and normalized to GAPDH. (E) GO orbital fibroblasts were stimulated with TGF-β1 (3 ng/mL) for 48 h with or without a 1-h pretreatment with geranylgeranyl transferase inhibitor (GGTI-298) (10 μM) or farnesyl transferase inhibitor (FTI-227) (10 μM). The α-SMA protein production was determined using western blot analysis. Data are presented as mean ± SD of at least three independent experiments. *p < 0.05.