Resveratrol inhibits transforming growth factor-β–induced proliferation and differentiation of ex vivo human lung fibroblasts into myofibroblasts through ERK/Akt inhibition and PTEN restoration

The authors investigated the role of resveratrol (RV), a natural poliphenolic molecule with several biological activities, in transforming growth factor-β (TGF-β)–induced proliferation and differentiation of ex vivo human pulmonary fibroblasts into myofibroblasts. The effects of RV treatment were evaluated by analyzing TGF-β–induced α-smooth muscle actin (α-SMA) expression and collagen production, as well as cell proliferation of both normal and idiopathic pulmonary fibrosis (IPF) lung fibroblasts. Results demonstrate that RV inhibits TGF-β–induced cell proliferation of both normal and pathological lung fibroblasts, attenuates α-SMA expression at both the mRNA and protein levels, and also inhibits intracellular collagen deposition. In order to understand the molecular mechanisms, the authors also investigated the effects of RV treatment on signaling pathways involved in TGF-β–induced fibrosis. The authors show that RV inhibited TGF-β–induced phosphorylation of both extracellular signal-regulated kinases (ERK1/2) and the serine/threonine kinase, Akt. Moreover, RV treatment blocked the TGF-β–induced decrease in phosphatase and tensin homolog (PTEN) expression levels.