Atorvastatin Attenuates Bleomycin-Induced Pulmonary Fibrosis via Suppressing iNOS Expression and the CTGF (CCN2)/ERK Signaling Pathway

Pulmonary fibrosis is a progressive and fatal lung disorder with high mortality rate. To date, despite the fact that extensive research trials are ongoing, pulmonary fibrosis continues to have a poor response to available medical therapy. Statins, 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors, known for its broad pharmacological activities, remains a remedy against multiple diseases. The present study investigated the antifibrotic potential of atorvastatin against bleomycin-induced lung fibrosis and to further explore the possible underlying mechanisms. Our results showed that atorvastatin administration significantly ameliorated the bleomycin mediated histological alterations and blocked collagen deposition with parallel reduction in the hydroxyproline level. Atorvastatin reduced malondialdehyde (MDA) level and lung indices. Atorvastatin also markedly decreased the expression of inducible nitric oxide synthase (iNOS) in lung tissues and, thus, prevented nitric oxide (NO) release in response to bleomycin challenge. Furthermore, atorvastatin exhibited target down-regulation of connective tissue growth factor (CTGF (CCN2)) and phosphorylation extracellular regulated protein kinases (p-ERK) expression. Taken together, atorvastatin significantly ameliorated bleomycin-induced pulmonary fibrosis in rats, via the inhibition of iNOS expression and the CTGF (CCN2)/ERK signaling pathway. The present study provides evidence that atorvastatin may be a potential therapeutic reagent for the treatment of lung fibrosis.