Roflumilast inhibits the release of chemokines and TNF-[alpha] from human lung macrophages stimulated with lipopolysaccharide

• Published in: British journal of pharmacology 2012-03, Vol.165 (6), p.1877
• Main Authors: Buenestado, A, Grassin-Delyle, S, Guitard, F, Naline, E, Faisy, C, Israel-Biet, D, Sage, E, Bellamy, JF, Tenor, H, Devillier, P
• Format: Article
• Language: English
• Subjects: Chemokines; Immune system; Ozone; Smog
• ISSN: 0007-1188; 1476-5381
• DOI: 10.1111/j.1476-5381.2011.01667.x

BACKGROUND AND PURPOSE Lung macrophages are critically involved in respiratory diseases. This study assessed the effects of the PDE4 inhibitor roflumilast and its active metabolite, roflumilast N-oxide on the release of a range of chemokines (CCL2, 3, 4, CXCL1, 8, 10) and of TNF-[alpha], from human lung macrophages, stimulated with bacterial lipopolysaccharide LPS. EXPERIMENTAL APPROACH Lung macrophages isolated from resected human lungs were incubated with roflumilast, roflumilast N-oxide, PGE2, the COX inhibitor indomethacin, the COX-2 inhibitor NS-398 or vehicle and stimulated with LPS (24 h). Chemokines, TNF-[alpha], PGE2 and 6-keto PGF1[alpha] were measured in culture supernatants by immunoassay. COX-2 mRNA expression was assessed with RT-qPCR. PDE activities were determined in macrophage homogenates. KEY RESULTS Expression of PDE4 in lung macrophages was increased after incubation with LPS. Roflumilast and roflumilast N-oxide concentration-dependently reduced the LPS-stimulated release of CCL2, CCL3, CCL4, CXCL10 and TNF-[alpha] from human lung macrophages, whereas that of CXCL1 or CXCL8 was not altered. This reduction by the PDE4 inhibitors was further accentuated by exogenous PGE2 (10 nM) but abolished in the presence of indomethacin or NS-398. Conversely, addition of PGE2(10 nM), in the presence of indomethacin restored inhibition by roflumilast. LPS also increased PGE2and 6-keto PGF1[alpha] release from lung macrophages which was associated with an up-regulation of COX-2 mRNA. CONCLUSIONS AND IMPLICATIONS Roflumilast and roflumilast N-oxide reduced LPS-induced release of CCL2, 3, 4, CXCL10 and TNF-[alpha] in human lung macrophages. [PUBLICATION ABSTRACT]