67675-14-3Relevant academic research and scientific papers
Inhibitory and mechanistic investigations of oxo-lipids with human lipoxygenase isozymes
Armstrong, Michelle M.,Diaz, Giovanni,Kenyon, Victor,Holman, Theodore R.
, p. 4293 - 4297 (2014/08/18)
Oxo-lipids, a large family of oxidized human lipoxygenase (hLOX) products, are of increasing interest to researchers due to their involvement in different inflammatory responses in the cell. Oxo-lipids are unique because they contain electrophilic sites that can potentially form covalent bonds through a Michael addition mechanism with nucleophilic residues in protein active sites and thus increase inhibitor potency. Due to the resemblance of oxo-lipids to LOX substrates, the inhibitor potency of 4 different oxo-lipids; 5-oxo-6,8,11,14-(E,Z,Z,Z)-eicosatetraenoic acid (5-oxo-ETE), 15-oxo-5,8,11,13-(Z,Z,Z,E)-eicosatetraenoic acid (15-oxo-ETE), 12-oxo-5,8,10,14-(Z,Z,E,Z)-eicosatetraenoic acid (12-oxo-ETE), and 13-oxo-9,11-(Z,E)-octadecadienoic acid (13-oxo-ODE) were determined against a library of LOX isozymes; leukocyte 5-lipoxygenase (h5-LOX), human reticulocyte 15-lipoxygenase-1 (h15-LOX-1), human platelet 12-lipoxygenase (h12-LOX), human epithelial 15-lipoxygenase-2 (h15-LOX-2), soybean 15-lipoxygenase-1 (s15-LOX-1), and rabbit reticulocyte 15-LOX (r15-LOX). 15-Oxo-ETE exhibited the highest potency against h12-LOX, with an IC50 = 1 ± 0.1 μM and was highly selective. Steady state inhibition kinetic experiments determined 15-oxo-ETE to be a mixed inhibitor against h12-LOX, with a Kic value of 0.087 ± 0.008 μM and a Kiu value of 2.10 ± 0.8 μM. Time-dependent studies demonstrated irreversible inhibition with 12-oxo-ETE and h15-LOX-1, however, the concentration of 12-oxo-ETE required (Ki = 36.8 ± 13.2 μM) and the time frame (k2 = 0.0019 ± 0.00032 s-1) were not biologically relevant. These data are the first observations that oxo-lipids can inhibit LOX isozymes and may be another mechanism in which LOX products regulate LOX activity.
Unified Mechanism for Polyunsaturated Fatty Acid Autooxidation. Competition of Peroxy Radical Hydrogen Atom Abstraction, β-Scission, and Cyclization
Porter, Ned A.,Lehman, Laura S.,Weber, Bruce A.,Smith, Karl J.
, p. 6447 - 6455 (2007/10/02)
The autooxidation of linoleic (18:2) and arachidonic (20:4) acids with several cosubstrates was investigated.Cumene, tetralin, 1,4-cyclohexadiene, and 9,10-dihydroanthracene in benzene were used as cosubstrates for the oxidation of linoleic acid.The distribution of products, trans,cis diene hydroperoxides and trans,trans diene hydroperoxides, was dependent on the ability of cosubstrates to donate hydrogen atoms to linoleate peroxy radicals.Arachidonic acid was oxidized in mixtures of benzene/1,4-cyclohexadiene with linoleic acid internal standard.Product distribution of six hydroperoxyeicosatetraenoic acids (HPETE) derived from arachidonic acid was established at different concentrations of 1,4-cyclohexadiene in the solvent mixture.A kinetic expression is derived that is useful in describing polyunsaturated fatty acid oxidation product mixtures.By the use of this kinetic derivation, the rate of cyclization of peroxy free radicals derived from arachidonic acid was determined.
