Effect of IL-1beta on CRE-dependent gene expression in human airway smooth muscle cells.
IL-1beta inhibits isoproterenol (ISO)-induced relaxation of cultured human airway smooth muscle (HASM) cells. The purpose of this study was to determine whether IL-1beta can also suppress ISO-induced cAMP response element (CRE)-dependent gene expression. ISO (10 microM) caused a marked increase in CRE-binding protein (CREB) phosphorylation, which was attenuated by IL-1beta (2 ng/ml). This effect of IL-1beta was abolished by the cyclooxygenase (COX) inhibitor indomethacin. To examine CRE-driven gene expression, we transiently transfected HASM cells with a construct containing CRE upstream of a luciferase reporter gene. ISO (6 h) caused a sixfold increase in luciferase activity. IL-1beta (24 h) alone also increased luciferase activity, although to a lesser extent (2-fold). However, the ability of ISO to elicit luciferase expression was markedly reduced in cells treated with IL-1beta. Indomethacin, the MEK and p38 inhibitors U-0126 and SB-203580, the protein kinase A inhibitor H-89, and dexamethasone each completely abolished the ability of IL-1beta to induce CRE-driven gene expression but only slightly increased the ability of ISO to induce CRE-driven gene expression in IL-1beta-treated cells. IL-1beta also attenuated dibutyryl cAMP-induced CRE-driven gene expression, but not dibutyryl cAMP-induced CREB phosphorylation. Tumor necrosis factor-alpha (10 ng/ml) also attenuated ISO-induced CRE-driven gene expression, even though it was without effect on ISO-induced cAMP formation or ISO-induced CREB phosphorylation. The results suggest that IL-1beta and tumor necrosis factor-alpha may attenuate the ability of beta-agonists to induce expression of genes with CRE in their regulatory regions at least in part through events downstream of CREB phosphorylation.
Lahiri
Thomas
T
Physiology Program, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
Moore
Paul E
PE
Baraldo
Simonetta
S
Whitehead
Timothy R
TR
McKenna
Matthew D
MD
Panettieri
Reynold A
RA
Shore
Stephanie A
SA
D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D003994:Bucladesine / Q000494:pharmacology; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000502:physiology*; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology*; D015850:Interleukin-6 / Q000235:genetics; D007545:Isoproterenol / Q000494:pharmacology; D009130:Muscle, Smooth / Q000166:cytology / Q000502:physiology*; D010766:Phosphorylation / Q000187:drug effects; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000502:physiology; D020218:Response Elements / Q000235:genetics / Q000502:physiology*; D014132:Trachea / Q000166:cytology / Q000502:physiology*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D000318:Adrenergic beta-Agonists; D017362:Cyclic AMP Response Element-Binding Protein; D007375:Interleukin-1; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D003994:Bucladesine; D000242:Cyclic AMP; D007545:Isoproterenol