Role of TGF-b1 in type I collagen production in bronchial epithelial cells: effects on Smad7 inhibitory role?

Airway epithelial cells play an important role in inflammatory, apoptotic and remodelling process associate with fibrosis and COPD. Transforming growth factor 1 (TGF-b1) is involved in airways remodelling by Smads signalling pathway. We investigated the role of TGF-b1 on type I collagen production and Smads (Smad 2-3-4-and 7) expression in bronchial epithelial cells (16HBE). Cells were treated with 1ng/ml and 10ng/ml of TGF-b1 for 0, 3 and 24 hours. With low dose of TGF-b1 we observed no significant variation on Smad2 mRNA expression for both times but a significant increased of Smad7 mRNA expression at 3h (p=0.0043) and a significant reduction of Smad3, Smad4 and Smad7 mRNA expression at 2…