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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Cell Hypoxia, Cells, Cultured, Endothelium, Vascular, Humans, Intercellular Adhesion Molecule-1, NF-kappa B, Reperfusion Injury, Tumor Necrosis Factor-alpha, Up-Regulation.
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Does hypertonic mannitol loading of NF-kappaB transcription factor decoys in human brain microvascular endothelial cells block upregulation of ICAM-1? Context: An acute inflammatory response exacerbates tissue injury during acute ischemic stroke. The transcription factor nuclear factor (NF)-kappaB plays a key role in endothelial cell activation and the inflammatory response. Targeted genetic disruption of NF-kappaB activation in cerebral endothelial cells may be protective in stroke. We determined whether a NF-kappaB transcription factor decoy (TFD) could block intercellular adhesion molecule (ICAM)-1 upregulation, an indicator of endothelial cell activation. We modeled ischemia-reperfusion in vitro by exposing cultured human brain microvascular endothelial cells (HBMEC) to tumor necrosis factor (TNF)-alpha and conditions of hypoxia-reoxygenation (H/R). Mannitol was used to load phosphothiorated oligonucleotides containing 3 copies of the kappaB binding sequences (TFDs) into cultured HBMEC. An NF-kappaB TFD, a mutated NF-kappaB TFD, and a scrambled TFD were studied for their effect on ICAM-1 mRNA levels and surface ICAM-1 by ELISA. Hyperosmolar loading with mannitol permitted rapid transfection of TFD into endothelial cell nuclei. The NF-kappaB TFD but not the mutated or scrambled TFD competed with a kappaB sequence for binding to nuclear extracts from HBMEC exposed to TNF-alpha. The NF-kappaB TFD blocked the TNF-alpha-induced and H/R-induced increase in ICAM-1 mRNA levels and the upregulation of surface ICAM-1.
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Mannitol delivers phosphothiorated oligonucleotides into cultured HBMEC. An NF-kappaB decoy blocks both TNF-alpha-induced and H/R-induced ICAM-1 upregulation in HBMEC. Targeted genetic disruption of endothelial NF-kappaB activation may be of benefit in acute ischemic stroke. Final Decision: yes