Study in human colon cancer cells HCT-116 of PPME photodynamic effect solubilized in DMPC liposomes; ; Jacobs, Nathalie et alConference (2005) Detailed reference viewed: 14 (4 ULg) Improvement by solubilization in DMPC liposomes of PPME photodynamic effect - A study in human colon cancer cells HCT-116; ; Jacobs, Nathalie et alConference (2005) Detailed reference viewed: 13 (7 ULg) Improvement by solubilization in DMPC liposomes of PPME photodynamic effect - A study in human colon cancer cells HCT-116; ; Jacobs, Nathalie et alConference (2004) Detailed reference viewed: 7 (1 ULg) A proinflammatory role for the cyclopentenone prostaglandins at low micromolar concentrations: Oxidative stress-induced extracellular signal-regulated kinase activation without NF-kappa B inhibitionBureau, Fabrice ; Desmet, Christophe ; et alin Journal of Immunology (2002), 168(10), 5318-5325 An anti-inflammatory role and therapeutic potential for cyclopentenone PGs (cyPGs) has been suggested, based on observations that levels of cyPGs in exudates increase during the resolution phase of ... [more ▼] An anti-inflammatory role and therapeutic potential for cyclopentenone PGs (cyPGs) has been suggested, based on observations that levels of cyPGs in exudates increase during the resolution phase of inflammation, and that exogenous cyPGs may attenuate the inflammatory response in vivo and in vitro mainly through inhibition of NF-kappaB, a critical activator of inflammatory gene expression. However, exogenous cyPGs inhibit NF-kappaB only at concentrations substantially higher than those of endogenous cyPGs present in inflammatory fluids, thus challenging the hypothesis that cyPGs are naturally occurring inhibitors of inflammation and suggesting that cyPGs at low concentrations might have previously unappreciated effects. In this study, using various cell types, we report that cyPGs, when used at concentrations substantially lower than required for NF-kappaB inhibition (viz, low micromolar concentrations), significantly potentiate the inflammatory response to TNF-alpha. At these concentrations, cyPGs induce production of reactive oxygen species, thereby synergizing with TNF-alpha to activate the extracellular signal-regulated kinase 1/2, an activation which in turn potentiates proinflammatory cytokine expression at both transcriptional and posttranscriptional levels. Our studs establishes a proinflammatory role for cyPGs at low micromolar concentrations, raises the possibility that cyPGs do not act as physiologic anti-inflammatory mediators, and questions the therapeutic potential of these compounds. [less ▲] Detailed reference viewed: 30 (9 ULg) Cyclopentenone prostaglandins at low concetrations exert pro-inflammatory effects through oxidative stress-induced ERK1/2 activationBureau, Fabrice ; Desmet, Christophe ; et alin Proceedings: Spring Meeting of the Belgian Society of Physiology and Pharmacology (2002) Detailed reference viewed: 8 (4 ULg) A pro-inflammatory role for the cyclopentenone prostaglandins at low concentrations: oxidative stress-induced ERK activation without NFKB inhibitionBureau, Fabrice ; Desmet, Christophe ; et alin Proceedings : Congress "Cell signaling, transcription and translation as therapeutics targets" (2002) Detailed reference viewed: 17 (7 ULg) Impairment of the mitochondrial electron chain transport prevents NF-kappa B activation by hydrogen peroxide.; ; et al in Free Radical Biology & Medicine (1998), 25(1), 104-112 A large body of work has been devoted to mechanisms leading to the activation of the transcription factor NF-kappa B in various cell types. Several studies have indicated that NF-kappa B activation by ... [more ▼] A large body of work has been devoted to mechanisms leading to the activation of the transcription factor NF-kappa B in various cell types. Several studies have indicated that NF-kappa B activation by numerous stimuli depends on the intracellular generation of reactive oxygen species (ROS). In this report, we first demonstrated that inhibition of the electron transport chain by either rotenone or antimycine A gave rise to dose-dependent inhibition of NF-kappa B translocation induced by 150 microM of hydrogen peroxide (H2O2). Conversely, the impairment of the mitochondrial respiratory chain did not affect T lymphocyte treatment by TNF-alpha (tumor necrosis factor alpha) or pre-B lymphocyte treatment with LPS (lipopolysaccharide). We also showed that oligomycine which inhibits ATP synthase and FCCP, which uncouples respiration also led to dose-dependent inhibition of NF-kappa B activation by H2O2. All these inhibitors were also shown to inhibit mitochondrial respiration in lymphocytes assessed by oxygen consumption. Although only a transient drop in ATP concentration was observed when lymphocytes were treated by H2O2, this effect was remarkably reinforced in the presence of oligomycine demonstrating the crucial role of ATP in the signal transduction pathway induced by H2O2. [less ▲] Detailed reference viewed: 7 (1 ULg) Photosensitized generation of hydroxyl radical by eught new sulfur and selenium analogs of psoralen; Hoebeke, Maryse ; et alin Journal of Photochemistry & Photobiology B : Biology (1996), 35 comparative study by ESR of the hydroxyl radical generation by 8 eight new sulfur and selenium analogs of psoralen Detailed reference viewed: 4 (2 ULg) Hydroxyl radical generation by new furocoumarin derivatives: a spin trapping and ESR study; Hoebeke, Maryse ; et alConference (1993) Detailed reference viewed: 3 (1 ULg) Type 1 and Type 2 photosensitization mechanisms induced by merocyanine 540 bound to DMPC liposomesHoebeke, Maryse ; ; Conference (1991) Detailed reference viewed: 9 (2 ULg) Viscosity-dependent isomerization and fluorescence yields of merocyanine 540Hoebeke, Maryse ; ; in Journal of Photochemistry & Photobiology B : Biology (1990), 52 Detailed reference viewed: 4 (0 ULg) Viscosity-dependent isomerization and fluorescence yields of merocyanine 540Hoebeke, Maryse ; ; Conference (1988) Detailed reference viewed: 2 (0 ULg) Singlet oxygen production by merocyanine 540Hoebeke, Maryse ; ; Conference (1987) Detailed reference viewed: 4 (2 ULg) |
||