Proteasome inhibitors block VCAM-1 and ICAM-1 gene expression in endothelial cells without affecting nuclear translocation of nuclear factor-kappa B.
Endothelial cells play a major role in recruiting leukocytes to sites of inflammation. This is accomplished, at least in part, by up-regulation of cell surface adhesion molecules, including VCAM-1 and ICAM-1, in response to cytokines. In this report, we investigated the role of the proteasome complex in mediating the interleukin (IL)- 1 beta induction of VCAM-1 and ICAM-1 gene expression in human endothelial cells. We present evidence that a proteasome inhibitor, n-acetyl-leucinyl-leucinyl-norleucinal (norLEU), as well as specific protease inhibitors, n-tosyl-Lys-chloromethylketone and N-tosyl-Phe-chloromethylketone, blocked IL-1 beta induction of VCAM-1 and ICAM-1 promoter-driven reporter gene expression in stably transfected endothelial cells. These inhibitors also blocked cytokine induced cell surface expression of VCAM-1 and ICAM-1 by human umbilical vein endothelial cells. As expected, the protease inhibitors blocked the activation of nuclear factor (NF)-kappa B in response to IL-1 beta stimulation. In contrast, norLEU did not prevent IL-1 beta-induced nuclear translocation of NF-kappa B. The effects of norLEU were specific because it did not inhibit the IL-1 beta induction of plasminogen activator inhibitor type 1 gene expression. This study demonstrates that inhibition of the proteolytic activity of the proteasome blocks IL-1 beta induction of VCAM-1 and ICAM-1 gene expression in human endothelial cells.
Cobb
R R
RR
Biology Department, Tanabe Research Laboratories, San Diego, CA 92121, USA.
Felts
K A
KA
Parry
G C
GC
Mackman
N
N
D001483:Base Sequence; D001692:Biological Transport / Q000187:drug effects; D002154:Calpain / Q000037:antagonists & inhibitors / Q000502:physiology*; D002467:Cell Nucleus / Q000378:metabolism*; D002478:Cells, Cultured; D003546:Cysteine Endopeptidases / Q000502:physiology*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis* / Q000235:genetics; D007375:Interleukin-1 / Q000494:pharmacology; D007976:Leupeptins / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000502:physiology*; D016328:NF-kappa B / Q000378:metabolism*; D017395:Plasminogen Activator Inhibitor 1 / Q000096:biosynthesis / Q000235:genetics; D011480:Protease Inhibitors / Q000494:pharmacology; D046988:Proteasome Endopeptidase Complex; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014107:Tosyllysine Chloromethyl Ketone / Q000494:pharmacology*; D014108:Tosylphenylalanyl Chloromethyl Ketone / Q000494:pharmacology*; D014162:Transfection; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis* / Q000235:genetics
D007375:Interleukin-1; D007976:Leupeptins; D009097:Multienzyme Complexes; D016328:NF-kappa B; D017395:Plasminogen Activator Inhibitor 1; D011480:Protease Inhibitors; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D019010:Vascular Cell Adhesion Molecule-1; C089487:acetyl-leucinyl-leucinyl-methional; C063261:acetylleucyl-leucyl-norleucinal; D018799:Intercellular Adhesion Molecule-1; D014107:Tosyllysine Chloromethyl Ketone; D014108:Tosylphenylalanyl Chloromethyl Ketone; D002154:Calpain; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex