Effect of exogenous hydrogen sulfide on transforming growth factor-β1 and connective tissue growth factor in lung tissue of pulmonary fibrosis rats

Objective To investigate the effect of exogenous hydrogen sulfide on transforming growth factor-(TGF-β1) and connec- tive tissue growth factor(CTGF) in lung tissue of pulmonary fibrosis Rats.Methods Fifty-four pathogen-free Male Wistar rats were ran- domly divided into three groups: control,pulmonary fibrosis model and NaHS(the H 2 S donor) and pulmonary fibrosis groups with 18 rats in each group.Rats in each group were then divided into three subgroups based on time of study(7-,14- and 28-days).Pulmonary fibrosis model was established by intrabronchus instillation of bleomycin(5 mg / kg).While control rats received saline,rats of the treated group sim- ultaneously were administered intraperitoneal injections of NaHS(28 μmol / kg) daily.Hydroxyproline level in lung homogenate was meas- ured by the alkaline hydrolysis assay.The expressions of TGF-β1 and CTGF in lung tissue were analyzed by ELISA.Results The content of HYP,TGF-β1 and CTGF in rat's lung tissue of pulmonary fibrosis group in each time point were significantly higher than that of control group(P0.01).The contents of HYP,TGF-β1 and CTGF in rat's lung tissue of pulmonary fibrosis model and NaHS group in each time point were significantly lower than those of pulmonary fibrosis group(P0.01,P0.05).TGF-β1 was correlated positively with CTGF in each time point of every group(r = 0.891 ~ 0.968,all P0.01).Conclusions Exogenous hydrogen sulfide ameliorates bleomycin-in- duced pulmonary fibrosis in rats through downregulation CTGF via inhibiting the TGF-β1 signal path.