Figure 5. Nintedanib suppresses Smad2/3, p38MAPK, and ERK1/2 activation induced by transforming growth factor β1 (TGF-β1) at later timepoints. Human Tenon’s fibroblasts (HTFs) were treated with TGF-β1 (5 ng/ml) in the presence or absence of SB203580 or nintedanib (1 μM) for 24 h. TGF-β1 and p-Smad2/3 (A), p-p38MAPK and p-ERK1/2 (B) mRNA and protein expression were analyzed by quantitative reverse transcription polymerase chain reaction (RT-PCR) and western blot, respectively, and normalized to total Smad2/3, ERK1/2, or GAPDH. Data are presented as the means ± standard deviations (SDs; n = 3) of independent repeated experiments (* p<0.01;**** p<0.0001 compared with the control or TGF-β1 group).