Abstract: AIM: To investigate the protective effect of Okam extract J201 on bleomycin induced pulmonary fibrosis in rats and the underlying mechanism.METHODS: Forty-six Wistar rats were randomly divided into four groups.Pulmonary fibrosis was induced by intratracheal instillation of bleomycin.The histopathological changes of the lungs, lung weight index, contents of malondialdehyde (MDA) and hydroxyproline (HYP) in lung homogenate were investigated, and the immunohistochemical techniques were used to investigate the expressions of factor associated suicide (Fas), Fas ligand (FasL), matrix metalloproteinases-9 (MMP-9) and tissue inhibitor of metalloproteinase-2(TIMP-2) with a view to evaluating the effects of J201.RESULTS: Dose-dependent improvement in lung histopathology induced by bleomycin was noted in J201-treated group.Lung weight index and the contents of MDA and HYP were reduced by addition of J201.There were also decreased expressions of Fas, FasL, MMP-9 and TIMP-2 by J201.Dose-dependent relationship was observed, and the expressions of Fas, FasL, MMP-9 and TIMP-2 of pulmonary fibrosis induced by bleomycin were inhibited in rats.The effect of J201 on lung index, MDA, HYP, Fas, FasL, MMP-9 and TIMP-2 was in a dose-dependent manner.CONCLUSION: J201 shows protective effects on the pulmonary fibrosis induced by bleomycin in rats.Antioxidation and inhibition of the expression of Fas, FasL, MMP-9 and TIMP-2 in lung tissues may be one of the underlying mechanisms.

Key words: Okam extract J201, pulmonary fibrosis, factor associated suicide, fas ligand, matrix metalloproteinases-9, tissue inhibitor of metalloproteinase-2