Abstract:Objective: To determine the effects of curcumin on bleomycin (BLM)-induced pulmonary fibrosis in rats. Method: One hundred and forty-four male Sprague-Dawley rats were randomized into 6 groups (24 rats in each group, model group, sham group, prednisone group (0.56 mg·kg-1·d-1), curcumin with low dose 5 mg group, curcumin with middle dose group 10 mg and curcumin with high dose group 20 mg per 100 g of body weight). Rats in all groups except in sham group were injected with BLM intratracheally. Curcumin with different doses were given by gavage one time everyday for 7, 14 and 28 days. Prednisone were given to rats in prednisone group, po, serving as the positive treatment group. On the 7th, 14th, 28th day, the lung functions (inspiratory resistance, maximal volutary ventilation, forced vital capacity, Fev 0.2/FVC, peak expiratory flow) were determinated in experimental rats, respectively, and the concentrations of hydroxyproline in lung homogenates of each rat were assayed. Result: Administration of curcumin in different doses improved lung functions of BLM-induced fibrotic rats in the all experimental days; and it decreased the concentration of hydroxyproline in lung homogenates compared with those levels in model control group; and it also lessened the hyperplasia of BLM-induced pulmonary fibrosis in rats. Conclusion: Administration of curcumin can suppress BLM induced pulmonary fibrosis indicated by improved respiratory function, as well as companied with low content of hydroxyproline in lung tissue of rats.