Abstract
Idiopathic pulmonary fibrosis is a chronic and progressive fibrotic lung disorder with unknown etiology and a high mortality rate. Tanshinone ⅡA (Tan ⅡA) is a lipophilic diterpene extracted from the Chinese herb Salvia miltiorrhiza Bunge with diverse biological functions. The present study was conducted to evaluate the effects of Tan ⅡA on bleomycin (BLM)‑induced pulmonary fibrosis in rats. Rats received an intraperitoneal injection of Tan ⅡA and normal rats were used as controls. Severe pulmonary edema, inflammation and fibrosis were observed in the BLM‑treated rats and the counts of total cells, neutrophils and lymphocytes were significantly increased in the bronchoalveolar lavage fluids of those rats. These pathological changes were markedly attenuated by subsequent treatment with Tan ⅡA. In addition, BLM‑induced increased expression of tumor necrosis factor‑α, interleukin (IL)‑1β, IL‑6, cyclooxygenase‑2, prostaglandin E2, malondialdehyde, inducible nitric oxide synthase and nitric oxide in rats, which was also suppressed by Tan ⅡA injection. The present findings suggest therapeutic potential of Tan ⅡA for pulmonary fibrosis.