title: A proteasome inhibitor reduces concurrent, sequential, and long-term IL-1 beta- and TNF-alpha-induced ECAM expression and adhesion.
abstract: A promising approach for reducing aberrant leukocyte-endothelial adhesion during pathological inflammation is to inhibit endothelial cell adhesion molecule (ECAM) expression at the transcription level. Several compounds have been shown to decrease cytokine-induced upregulation of ECAMs primarily by modulating the activity of transcription factors [e.g., nuclear factor-kappa B (NF-kappa B)]. The majority of the in vitro studies have focused on the effect of transcription inhibitors on endothelial cells exposed to a single cytokine [primarily tumor necrosis factor-alpha (TNF-alpha)] for a relatively short period of time (primarily 4-6 h). However, in the in vivo setting, multiple cytokines [e.g., interleukin-1 beta (IL-1 beta) and TNF-alpha] may be present for extended periods of time. Thus we studied the effects of a transcription inhibitor, the proteasome inhibitor lactacystin, on ECAM expression and myeloid (HL60) cell adhesion to human umbilical vein endothelial cells (HUVEC) activated by concurrent, sequential, and long-term (24 h) treatment with IL-1 beta and TNF-alpha. We show, for the first time, that lactacystin inhibits 1) 4-h concurrent IL-1 beta- and TNF-alpha-induced expression of E-selectin, VCAM-1, ICAM-1, and HL60 cell adhesion to HUVEC; 2) 4-h TNF-alpha-induced expression of E-selectin, VCAM-1, and HL60 cell adhesion to HUVEC that have become desensitized to IL-1 beta activation; 3) 24-h TNF-alpha-induced expression of E-selectin and VCAM-1 but not ICAM-1; and 4) 24-h TNF-alpha-induced HL60 cell adhesion to HUVEC. Combined, our results demonstrate that a proteasome inhibitor can reduce concurrent, sequential, and long-term IL-1 beta- and TNF-alpha-induced ECAM expression and myeloid cell adhesion.
authors.affiliation: Department of Chemical Engineering, Ohio University, Athens, OH 45701, USA.
authors.forename: Nilesh M
authors.initials: NM
authors.lastname: Dagia
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Goetz
mesh_terms: D000111:Acetylcysteine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002448:Cell Adhesion / Q000187:drug effects; D015815:Cell Adhesion Molecules / Q000037:antagonists & inhibitors* / Q000502:physiology; D002478:Cells, Cultured; D003546:Cysteine Endopeptidases / Q000187:drug effects*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology*; D004351:Drug Resistance; D019040:E-Selectin / Q000378:metabolism; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D007375:Interleukin-1 / Q000494:pharmacology*; D009097:Multienzyme Complexes / Q000187:drug effects*; D022423:Myeloid Cells / Q000187:drug effects / Q000502:physiology; D046988:Proteasome Endopeptidase Complex; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism
chemical_list: D015815:Cell Adhesion Molecules; D015853:Cysteine Proteinase Inhibitors; D019040:E-Selectin; D007375:Interleukin-1; D009097:Multienzyme Complexes; D014409:Tumor Necrosis Factor-alpha; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; C067713:lactacystin; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex; D000111:Acetylcysteine