Comparison of the effects of two long-acting beta2-agonists on cytokine secretion by human airway epithelial cells.
OBJECTIVE
Long-acting beta2-agonists (LABAs) have proved to be useful in the management of asthma and prevention of exacerbations. LABAs can modulate inflammatory and repair processes in the airways of individuals affected by many respiratory disorders. This study assessed the effects of LABAs on the release of inflammatory mediators by bronchial epithelia.


METHODS
The effects of the LABAs salmeterol and formoterol on the synthesis of soluble interleukin-8 (IL-8), granulocyte-macrophage colony-stimulating factor (GM-CSF), and vascular endothelial growth factor (VEGF) in the human airway epithelial cell line A549 was investigated in vitro. Cells cultured for 8 h in the presence of an LABA were stimulated with tumor necrosis factor-alpha for 16 h and then enzyme-linked immunosorbent assays for IL-8, GM-CSF, and VEGF were performed on the supernatants.


RESULTS
Both salmeterol and formoterol significantly suppressed IL-8, GM-CSF, and VEGF secretion from tumor necrosis factor-alpha-stimulated A549 cells. Results indicated that formoterol was more potent than salmeterol in suppressing IL-8 and VEGF production. In contrast, salmeterol appeared to be more potent than formoterol in suppressing GM-CSF production.


CONCLUSIONS
LABAs have some anti-inflammatory effects on bronchial epithelia. The differences between salmeterol and formoterol and mechanisms for the observed effects need further evaluation.
Chiu
Jou Chia
JC
Division of Immunology and Nephrology, Department of Pediatrics, Taichung Veterans General Hospital, Taichung, Taiwan.
Hsu
Jeng Yuan
JY
Fu
Lin Shien
LS
Chu
Jao Jia
JJ
Chi
Chin Shiang
CS
D058666:Adrenergic beta-2 Receptor Agonists; D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000420:Albuterol / Q000031:analogs & derivatives* / Q000494:pharmacology; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D002460:Cell Line; D016207:Cytokines / Q000096:biosynthesis*; D004847:Epithelial Cells / Q000187:drug effects*; D004983:Ethanolamines / Q000494:pharmacology*; D000068759:Formoterol Fumarate; D006801:Humans; D020545:Respiratory Mucosa / Q000187:drug effects*; D000068299:Salmeterol Xinafoate
D058666:Adrenergic beta-2 Receptor Agonists; D000318:Adrenergic beta-Agonists; D000893:Anti-Inflammatory Agents; D016207:Cytokines; D004983:Ethanolamines; D000068299:Salmeterol Xinafoate; D000420:Albuterol; D000068759:Formoterol Fumarate