AUTHOR=Salvator Hélène , Buenestado Amparo , Brollo Marion , Naline Emmanuel , Victoni Tatiana , Longchamp Elisabeth , Tenor Hermann , Grassin-Delyle Stanislas , Devillier Philippe TITLE=Clinical Relevance of the Anti-inflammatory Effects of Roflumilast on Human Bronchus: Potentiation by a Long-Acting Beta-2-Agonist JOURNAL=Frontiers in Pharmacology VOLUME=11 YEAR=2020 URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2020.598702 DOI=10.3389/fphar.2020.598702 ISSN=1663-9812 ABSTRACT=

Background: Roflumilast is an option for treating patients with severe COPD and frequent exacerbations despite optimal therapy with inhaled drugs. The present study focused on whether the phosphodiesterase (PDE) 4 inhibitor roflumilast and its active metabolite roflumilast N-oxide affect the release of tumor necrosis factor (TNF)-α and chemokines by lipopolysaccharide (LPS)-stimulated human bronchial explants. We also investigated the interactions between roflumilast, roflumilast N-oxide and the β2-agonist formoterol with regard to cytokine release by the bronchial preparations.

Methods: Bronchial explants from resected lungs were incubated with roflumilast, roflumilast N-oxide and/or formoterol and then stimulated with LPS. An ELISA was used to measure levels of TNF-α and chemokines in the culture supernatants.

Results: At a clinically relevant concentration (1 nM), roflumilast N-oxide and roflumilast consistently reduced the release of TNF-α, CCL2, CCL3, CCL4, CCL5 and CXCL9 (but not CXCL1, CXCL5, CXCL8 and IL-6) from human bronchial explants. Formoterol alone decreased the release of TNF-α, CCL2, and CCL3. The combination of formoterol with roflumilast (1 nM) was more potent than roflumilast alone for inhibiting the LPS-induced release of TNF-α, CCL2, CCL3, CCL4, and CXCL9 by the bronchial explants.

Conclusions: At a clinically relevant concentration, roflumilast N-oxide and its parent compound, roflumilast, reduced the LPS-induced production of TNF-α and chemokines involved in monocyte and T-cell recruitment but did not alter the release of chemokines involved in neutrophil recruitment. The combination of formoterol with roflumilast enhanced the individual drugs’ anti-inflammatory effects.