TNF-alpha upregulates VCAM-1 and NF-kappaB in fibroblasts from nasal polyps.
OBJECTIVE
Lung and synovial fibroblasts produce VCAM-1 in response to TNF-alpha. However, the massive infiltration of eosinophils, the effects of the increased amount of TNF-alpha and the production of VCAM-1 in human nasal polyp fibroblasts are not yet fully understood. The present study examines the role of VCAM-1 and the molecular mechanism of its expression in nasal fibroblasts.


METHODS
Nasal fibroblasts were isolated from human nasal polyps and after four passages, the cells were stimulated with TNF-alpha and VCAM-1 expression was examined by ELISA, flow cytometry, and RT-PCR. The activation of NF-kappaB induced by TNF-alpha was determined by electrophoretic mobility shift assays and the influence on the expression of VCAM-1 was investigated.


RESULTS
VCAM-1 protein and mRNA were expressed in unstimulated controls and remarkably increased by TNF-alpha stimulation. NF-kappaB activity was enhanced by TNF-alpha stimulation and remarkably suppressed by NF-kappaB proteasome inhibitor.


CONCLUSIONS
The present study discovered that nasal fibroblasts produce VCAM-1 protein and mRNA and that production is increased by TNF-alpha stimulation. Furthermore, VCAM-1 expression in nasal fibroblasts is induced through an NF-kappaB-dependent pathway. These findings might provide a rationale for using NF-kappaB inhibitors as a treatment for nasal inflammatory diseases such as polyps.
Ohori
Junichiro
J
Department of Otolaryngology, Field of Sensory Organology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1, Sakuragaoka, Kagoshima 890-8520, Japan. juno@m3.kufm.kagoshima-u.ac.jp
Ushikai
Masato
M
Sun
Dong
D
Nishimoto
Kengo
K
Sagara
Yukari
Y
Fukuiwa
Tatsuya
T
Matsune
Shoji
S
Kurono
Yuichi
Y
D002478:Cells, Cultured; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D024202:Electrophoretic Mobility Shift Assay; D004797:Enzyme-Linked Immunosorbent Assay; D005347:Fibroblasts / Q000473:pathology; D005434:Flow Cytometry; D006801:Humans; D066298:In Vitro Techniques; D007976:Leupeptins / Q000494:pharmacology; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009298:Nasal Polyps / Q000473:pathology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014409:Tumor Necrosis Factor-alpha / Q000502:physiology*; D015854:Up-Regulation / Q000502:physiology; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism*
D015853:Cysteine Proteinase Inhibitors; D007976:Leupeptins; D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D019010:Vascular Cell Adhesion Molecule-1; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde