Role for nuclear factor-kappaB and signal transducer and activator of transcription 1/interferon regulatory factor-1 in cytokine-induced endothelin-1 release in human vascular smooth muscle cells.
Endothelin-1 (ET-1) is a potent vasoconstrictor and growth-promoting mediator that is involved in the maintenance of vascular tone within the healthy circulation. However, a pathogenic role has been implicated by its overproduction in a number of cardiovascular diseases, which include pulmonary hypertension, congestive heart failure, atherosclerosis, and coronary vasospasm. ET-1 mRNA expression and peptide production in human vascular smooth muscle cells (HVSMCs) are markedly increased by exposure to tumor necrosis factor-alpha and interferon-gamma. The intracellular signaling mechanism involved in this pathway is not known. Because the transcription factors nuclear factor-kappaB (NF-kappaB), signal transducer and activator of transcription 1 (STAT1), and interferon regulatory factor-1 (IRF-1) often mediate the effects of cytokines in target cells the aim of this study was to determine whether the production of ET-1 after exposure of HVSMCs to cytokines depends upon synergism between NF-kappaB and STAT1/IRF-1. Immunoblotting showed that cytokine-stimulation of ET-1 release in VSMCs involves nuclear translocation of NF-kappaB and STAT1. Cytokines also induced an increase in IRF-1 protein expression. Antisense oligonucleotides to NF-kappaB, STAT1, and IRF-1 significantly inhibited cytokine induced ET-1 release. In conclusion, NF-kappaB, STAT1, and IRF-1 activation are involved in the stimulation by cytokines of ET-1 release from HVSMCs. However, nuclear run-on assays would provide definitive proof that ET-1 is regulated transcriptionally by cytokines. Because up-regulated production of ET-1 within VSMCs may underlie the causative role of ET-1 in a number of disease states, this finding indicates that NF-kappaB, STAT1, and IRF-1 within HVSMCs could be central to a number of vascular pathologies and that inhibition of this pathway could be of therapeutic benefit.
D021581:Active Transport, Cell Nucleus; D001692:Biological Transport; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D016207:Cytokines / Q000494:pharmacology*; D004268:DNA-Binding Proteins / Q000502:physiology*; D003609:Dactinomycin / Q000494:pharmacology; D019332:Endothelin-1 / Q000378:metabolism*; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D050856:Interferon Regulatory Factor-1; D007371:Interferon-gamma / Q000494:pharmacology; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000502:physiology*; D010750:Phosphoproteins / Q000502:physiology*; D010766:Phosphorylation; D012333:RNA, Messenger; D050794:STAT1 Transcription Factor; D015534:Trans-Activators / Q000502:physiology*; D014158:Transcription, Genetic; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D016207:Cytokines; D004268:DNA-Binding Proteins; D019332:Endothelin-1; C083487:I kappa B beta protein; D020672:I-kappa B Proteins; C494257:IRF1 protein, human; D050856:Interferon Regulatory Factor-1; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D010750:Phosphoproteins; D012333:RNA, Messenger; D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human; D015534:Trans-Activators; D014409:Tumor Necrosis Factor-alpha; D000072000:NF-KappaB Inhibitor alpha; D003609:Dactinomycin; D007371:Interferon-gamma; D003513:Cycloheximide