SMAD3 and pulmonary fibrosis: In our study, through inhibition of AGE formation in BLM-induced lung fibrosis by AG treatment, the expressions of TGFβ1, p-Smad2 and p-Smad3 were all downregulated dose-dependently, suggesting TGFβ/Smads signaling pathway probably plays a role in AGE-regulated HSP47 expression induced by BLM, although this link still needs more evidences to confirm.