1-1-diphenyl-2-picrylhydrazyl and 1-10-phenanthroline

Cobalt(II) complexes with a series of non-steroidal anti-inflammatory drugs (diflunisal, flufenamic acid, mefenamic acid and niflumic acid) in the presence of nitrogen-(2,2'-bipyridylamine, 2,2'-bipyridine, 1,10-phenanthroline) and/or oxygen-donor ligands (methanol) have been synthesized and characterized with physicochemical and spectroscopic techniques. The deprotonated NSAID ligands are coordinated to Co(II) ion through their carboxylato groups in diverse binding modes. The crystal structures of complexes [Co(diflunisal-O)2(methanol)4], [Co(niflumato-O)2(methanol)4], [Co(flufenamato-O,O')2(2,2'-bipyridylamine)], [Co(mefenamato-O,O')2(2,2'-bipyridylamine)] and [Co3(flufenamato-O,O')4(flufenamato-O,O,O')2(2,2'-bipyridine)2] have been determined by X-ray crystallography. The interaction of the complexes with serum albumins was studied by fluorescence emission spectroscopy and the albumin-binding constants were determined. The ability of the complexes to scavenge 1,1-diphenyl-picrylhydrazyl, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and hydroxyl radicals was investigated and the complexes were more active than the corresponding free drugs. Spectroscopic (UV and fluorescence), electrochemical (cyclic voltammetry) and physicochemical (viscosity measurements) techniques were employed in order to study the binding mode of the complexes to calf-thymus (CT) DNA and to calculate the corresponding binding constants; for all complexes, intercalation was suggested as the most possible DNA-binding mode.

Topics: 2,2'-Dipyridyl; Aminopyridines; Anti-Inflammatory Agents, Non-Steroidal; Binding Sites; Biphenyl Compounds; Cations, Divalent; Cobalt; Coordination Complexes; Crystallography, X-Ray; Diflunisal; DNA; Flufenamic Acid; Free Radical Scavengers; Intercalating Agents; Kinetics; Mefenamic Acid; Methanol; Models, Molecular; Niflumic Acid; Phenanthrolines; Picrates; Serum Albumin

The reaction of NiCl

Topics: 2,2'-Dipyridyl; Aminopyridines; Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzothiazoles; Binding, Competitive; Biphenyl Compounds; Cattle; Coordination Complexes; Crystallography, X-Ray; Diflunisal; DNA; Ethidium; Free Radical Scavengers; Hydroxyl Radical; Models, Molecular; Nickel; Phenanthrolines; Picrates; Protein Binding; Serum Albumin; Sulfonic Acids

From the reaction of Cu(II) with the non-steroidal anti-inflammatory drug ketoprofen (Hketo), complex [Cu

Topics: 2,2'-Dipyridyl; Aminopyridines; Animals; Anti-Inflammatory Agents, Non-Steroidal; Benzothiazoles; Binding, Competitive; Biphenyl Compounds; Cattle; Coordination Complexes; Copper; Crystallography, X-Ray; DNA; Ethidium; Free Radical Scavengers; Hydroxyl Radical; Ketoprofen; Models, Molecular; Phenanthrolines; Picrates; Protein Binding; Serum Albumin; Sulfonic Acids

ICAM-1 upregulation by endothelial cells plays a pivotal role in many disease processes, but signalling mechanisms leading to increased expression are poorly understood. In the current study we investigated the regulatory capacity of reactive oxygen intermediates (ROIs) in ICAM-1 activation by stimulating endothelial cells with the pro-inflammatory cytokines IL-1 beta, TNF alpha, IFN gamma, IL-2, and IL-4 prior to antioxidant treatment. ICAM-1 was expressed constitutively and upregulated on ECV304 by IL1-beta, IL2, and IFN gamma and on SKHEP-1 by IFN gamma, IL1-beta, and TNF alpha. Phenanthroline (PHE) and disulfiram (DIS) showed the greatest ability to inhibit cytokine-stimulated ICAM-1 expression and in a dose-dependent manner. The alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) conversion assay showed that PHE and DIS had zero ability to scavenge free radicals and thus no known antioxidant activity. However, both are known metal chelators and our findings therefore suggest a unique role for metal ions in the control of cytokine-induced ICAM-1 expression on endothelial cells.

Topics: Antioxidants; Bepridil; Biphenyl Compounds; Cell Line; Chelating Agents; Cytokines; Disulfiram; Endothelium, Vascular; Flow Cytometry; Free Radicals; Humans; Intercellular Adhesion Molecule-1; Interferon-gamma; Interleukins; Phenanthrolines; Picrates; Reactive Oxygen Species; Signal Transduction; Tumor Necrosis Factor-alpha; Up-Regulation