TIMP1 and Duchenne muscular dystrophy: Consistent with this, we found enhanced levels of active Smad2/3 (as indicated by phosphorylated Smad2/3) (Figure 1D) and TGFβ target genes such as Coll I, FN, tissue inhibitor of metalloproteinases 1 (TIMP-1) and CTGF, indicative of functional TGFβ signaling in fibrotic DMD muscle (Figure 1E).