Pulmonary fibrosis (PF) leads to chronic inflammation and accumulation of macrophages, neutrophils, and lymphocytes in the alveoli. The factors involved in the development of PF include reactive oxygen species and tissue remodelling regulators. The present study demonstrates the effect of andrographolide on bleomycin (BLM)-induced PF in Sprague-Dawley rats. We investigated the total bronchoalveolar lavage fluid protein (BALF) and hydroxyproline (HYP) content along with the level of oxidative stress markers like malondialdehyde (MDA) and GSH/GSSG ratio. In addition, the levels of MMP-1 and TIMP-1 were also analysed. The results revealed an increase in BALF protein, HYP, and MDA contents and decrease in GSH/GSSG ratio of the lungs in animals treated with BLM. However, andrographolide treatment caused a reversal of the BLM induced changes after 20 or 40 days. Treatment with andrographolide suppressed oxidative stress with the decrease of MDA and the increase of the GSH/GSSG ratio. Andrographolide also improved the BLM mediated changes in the MMP-1/TIMP-1 ratio. Therefore, andrographolide has a potential therapeutic effect in the prevention of PF.
Keywords: Hydroxyproline; bronchoalveolar; inflammation; lymphocytes; macrophages.