Dexamethasone attenuates bleomycin-induced lung fibrosis in mice through TGF-β, Smad3 and JAK-STAT pathway.

In order to find the possible mechanism of Dexamethasone (Dex) during curing fibrosis, the bleomycin (BLM)-induced mice model was used. After fibrosis were induced by BLM, histopathological evaluation and RT-PCR were employed to detect the expression of TGF-β1, Smad3 and STAT1. It was found that BLM promoted the development of inflammation, leading to severe pulmonary fibrosis with the increasing of TGF-β1, Smad3 and STAT1. After Dex treatment, the expression of TGF-β1, Smad3 and STAT1 showed a little higher with alleviation of the fibrosis. Thus it is concluded that there is a possible pathway of mouse pulmonary fibrosis model through TGF-β, Smad3 and JAK-STAT pathway.