Background and purpose: Idiopathic pulmonary fibrosis (IPF) is a fatal respiratory disease characterized by excessive fibroblast activation ultimately leading to scarring of the lungs. Although, the activation of β2 -adrenoceptors (β2 -AR) has been shown to inhibit pro-fibrotic events primarily in cell lines, the role of β2 -adrenoceptor agonists has not yet been fully characterized. The aim of our study was to explore the anti-fibrotic activity of the long-acting β2 -adrenoceptor agonist olodaterol in primary human lung fibroblasts (HLF) and in murine models of pulmonary fibrosis.
Experimental approach: We assessed the activity of olodaterol to inhibit various pro-fibrotic mechanisms, induced by different pro-fibrotic mediators, in primary HLF from control donors and patients with IPF (IPF-LF). The in vivo anti-fibrotic activity of olodaterol, given once daily by inhalation in either a preventive or therapeutic treatment regimen, was explored in murine models of lung fibrosis induced by either bleomycin or the overexpression of TGF-β1.
Key results: In both HLF and IPF-LF, olodaterol attenuated TGF-β-induced expression of α-smooth muscle actin, fibronectin and endothelin-1 (ET-1), FGF- and PDGF-induced motility and proliferation and TGF-β/ET-1-induced contraction. In vivo olodaterol significantly attenuated the bleomycin-induced increase in lung weight, reduced bronchoalveolar lavage cell counts and inhibited release of pro-fibrotic mediators (TGF-ß, MMP-9 and tissue inhibitor of metalloproteinase-1). Forced vital capacity was increased only with the preventive treatment regimen. In the TGF-β-overexpressing model, olodaterol additionally reduced the Col3A1 mRNA expression.
Conclusion and implications: Olodaterol showed anti-fibrotic properties in primary HLF from control and IPF patients and in murine models of lung fibrosis.
© 2017 The British Pharmacological Society.