[Effects of TNF-alpha on IL-8 mRNA expression in endothelial cells].
As a kind of chemokine, IL-8 plays an important role in inflammatory reaction. Its expression in endothelial cells is regulated by a variety of cytokines. In this study, after incubating cultured human umbilical vein endothelial cells(HUVECs) with TNF-alpha for different time, we employed RT-PCR to assay IL-8 mRNA expression and immunocytochemical staining to detect NF-kappa B activation in HUVECs. The results revealed: (1) IL-8 mRNA expressed little in untreated HUVECs; after HUVECs was pre-incubated with TNF-alpha for 1 hour, IL-8 mRNA expression increased greatly, and it increased further after pre-incubated for 3 hours; however, when HUVECs was pre-incubated with TNF-alpha for 6 hours, IL-8 mRNA expression decreased, and it almost decreased to basal level when pre-incubated for 9 hours; (2) the immunoreactivity of NF-kappa B p65 in the nuclei of untreated HUVECs was negative; it became positive in the nuclei of HUVECs pre-incubated with TNF-alpha for 1 hour and 3 hours; it became weak positive in the nuclei of HUVECs pre-incubated with TNF-alpha for 6 hours, and after 9 hours, pre-incubation, the immunoreactivity of NF-kappa B p65 in the nuclei of HUVECs was negative. These results implied that TNF-alpha was capable of inducing IL-8 gene expression and activation NF-kappa B. and Their time courses were similar, thus suggesting that the induction of IL-8 gene expression by TNF-alpha is probably due to the activation of NF-kappa B.
Wu
L
L
Research Unit of Biomedical Engineering, West China University of Medical Sciences, Chengdu 610041.
Chen
H
H
Chen
Y
Y
Wang
B
B
D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000235:genetics; D016328:NF-kappa B / Q000187:drug effects* / Q000502:physiology; D012333:RNA, Messenger / Q000096:biosynthesis; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D014471:Umbilical Veins / Q000166:cytology
D016209:Interleukin-8; D016328:NF-kappa B; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha