Lipoxygenase activity

Hatzelman, A. and Ullrich, V. (1987). Regulation of 5-lipoxygenase activity by the glutathione status in human polymorphonuclear leukocytes. Eur. J. Biochem. 169, 175-184. 

Fe-TPAA Fe(III)-tris[N-(2-pyridylmethyl)-2-aminoethyl] amine Fe-TPEN Fe(II)-tetrakis-N,N,N, N -(2-pyridyl methyl-2-aminoethyl)amine FFA Free fatty acids FGF Fibroblast growth factor FID Flame ionization detector FITC Fluorescein isothiocyanate FKBP FK506-binding protein FLAP 5-lipoxygenase-activating protein... 

A significant advance in the understanding of the anti-inflammatory properties of Bupleurum fruticescens has been provided by Prieto et al. (36). The showed that a methanol extract from the aerial parts had a significant effect on 5-lipoxygenase activity, inhibiting both LTB4 and 5(S)-HETE production, with IC50 values of 112 and 95 (xg/mL, respectively. At concentrations of 200 (Xg/mL, the extract inhibited COX-1 (90%) and elastase activities (54%). What are the principles involved here, saponin ... 

Zhuang H, Barth MM and Hildebrand DF. 1994. Packaging influenced total chlorophyll, soluble protein, fatty acid composition and lipoxygenase activity in broccoli florets. J Food Sci 59(6) 1171-1174. 

Long ago it was noticed that the baking quality of white flour improved with storage for 1-2 months. This effect occurred more rapidly if the flour was exposed to the air. During storage, initially the level of free fatty acids increases, presumably owing to lipolytic activity. Lipoxygenase activity then produces oxidised fatty acids as the proportion of linoleic and linolenic acids falls while the number of -S-S- bonds decreases. 

Lipoxygenase activating MK886 A549 Pathway analysis identifies [14]... 

An intravenous infusion of PAF causes rapid (within 60 s) intravascular platelet aggregation, thrombocytopenia and platelet factor 4 release, as well as a profound and reversible neutropenia, due to enhanced aggregation and adherence of these cells. In vitro, PAF effects on neutrophils are dependent upon extracellular Ca2+ and Mg2+ and occur within 60 s of addition. The addition of inhibitors of 5-lipoxygenase activity (e.g. ETYA, 5,8,11,14-eicosatetraenoic acid and NDGA, nordihydroguaiaretic acid) - but not those... 

Neutrophil preparations stimulated with A23187 also generate products of 15 -lipoxygenase activity, such as LTC4. However, most neutrophil preparations also contain eosinophils (usually about 2-5% contamination of the neutrophils). In contrast to neutrophils, which generate large quantities of... 

Flynn DL, Rafferty MF, Boctor AM. (1986). Inhibition of human neutrophil 5-lipoxygenase activity by gingerdione, shogaol, capsaicin and related pungent compounds. Prostaglandins Leukot Med. 24(2-3) 195-98. 

Kedda MA, Worsley P, Shi J, Phelps S, Duffy D, Thompson PJ. (2005) Polymorphisms in the 5-lipoxygenase activating protein (ALOX5AP) gene are not associated with asthma in an Australian population. Clin Exp Allergy. 35, 332-338. 

Ben-Asher E, Lancet D. (2004) 5-Lipoxygenase activating protein (ALOX5AP) association with cardiovascular infarction and stroke. Isr Med Assoc J. 6, 318-319. 

B. Reaction of Myoglobin with Hydrogen Peroxide Lipoxygenase Activity... 

Finally there has been a growing interest in the development of selective leukotriene inhibitors. Bay Y 1015 (R-(-)-2-cycloheptyl-N-methylsulfonyl-(4-(2-quinolinyl-methoxy) phenyl)-acetamide) is a quinoline-type 5-lipoxygenase-activating protein inhibitor which was effective in inhibiting inflammation in a dextran sulfate model of mouse colitis [112]. Whether these compounds can also exert their anti-inflammatory action through inhibition of endothelial cell activation needs to be established. 

Helgadottir A, Manolescu A, Thorleifsson G, et al. The gene encoding 5-lipoxygenase activating protein confers risk of myocardial infarction and stroke. Nat Genet. Mar 2004 36(3) 233-239. 

Kohyama, N., T. Nagata, S. I. Fuji-moto, and K. Sekiya. Inhibition of arachidonate lipoxygenase activities by 2-(3-4-dihydroxyphenyl) ethanol, a OE066 phenolic compounds from olives. Bio-sci Biotech Biochem 1997 61(2) ... 

Table III shows that l-octen-3-ol and 2-heptenal were only detected in soya containing bread and that the latter has significant larger peak areas of 1-pentanol, 1-hexanol, l-penten-3-ol, hexanal and 2- heptanone compared to the control (p < 0.05). These differences could be caused either by addition of volatile compounds present in soya flour or by its lipoxygenase activity. The main volatile compound found in soya flour was limonene (75), of which the peak areas were similar in the soya flour containing bread and its control sample. Moreover minor volatile compounds of soya flour, like 1-pentanol, 1-hexanol and hexanal, increased steadily in soya samples, as can be seen in Table...

III. These results indicate that the composition of volatile compounds of soya containing white bread is hardly influenced by the volatile compounds of the soya flour itself and that lipoxygenase activity plays a major role. 

Melons stored at low temperatures showed different relative amounts of volatiles recovered by solvent extraction [34]. Some of the C9 unsaturated esters and alcohols presumably originated as a result of lipoxygenase activity. The previous results together with some investigations of the C9 unsaturated esters and alcohols suggested that the activity of lipoxygenase on melons seems to be dependent on cultivar, age, storage conditions, and sample location [65]. 

NSAIDs usually do not inhibit lipoxygenase activity at concentrations that inhibit COX activity. In fact, by preventing arachidonic acid conversion via the COX pathway, NSAIDs may cause more substrate to be metabolized through the lipoxygenase pathways, leading to an increased formation of the inflammatory leukotrienes. Even among the COX-dependent pathways, inhibiting the... 

Inhibitory effects (IC30 SD, N=3, pmol/L) on arachidonate 5-lipoxygenase activity ... 

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