61641-47-2Relevant articles and documents
COX-2-dependent and -independent biosynthesis of dihydroxy-arachidonic acids in activated human leukocytes
Tejera, Noemi,Boeglin, William E.,Suzuki, Takashi,Schneider, Claus
scheme or table, p. 87 - 94 (2012/03/26)
Biosynthesis of 5,15-dihydroxyeicosatetraenoic acid (5,15-diHETE) in leukocytes involves consecutive oxygenation of arachidonic acid by 5-lipoxygenase (LOX) and 15-LOX in either order. Here, we analyzed the contribution of cyclooxygenase (COX)-2 to the biosynthesis of 5,15-di-HETE and 5,11-diHETE in isolated human leukocytes activated with lipopolysaccharide and calcium ionophore A23187. Transformation of arachidonic acid was initiated by 5-LOX providing 5 S -HETE as a substrate for COX-2 forming 5 S,15 S -diHETE, 5 S,15 R -diHETE, and 5 S,11 R -di-HETE as shown by LC/MS and chiral phase HPLC analyses. The levels of 5,15-diHETE were 0.45 ± 0.2 ng/106 cells (mean ± SEM, n = 6), reaching about half the level of LTB 4 (1.3 ± 0.5 ng/106 cells, n = 6). The COX-2 specific inhibitor NS-398 reduced the levels of 5,15-diHETE to below 0.02 ng/106 cells in four of six samples. Similar reduction was achieved by MK-886, an inhibitor of 5-LOX activating protein but the above differences were not statistically significant. Aspirin treatment of the activated cells allowed formation of 5,15-diHETE (0.1 ± 0.05 ng/106 cells, n = 6) but, as expected, abolished formation of 5,11-diHETE. The mixture of activated cells also produced 5 S,12 S -diHETE with the unusual 6 E,8 Z,10 E double bond configuration, implicating biosynthesis by 5-LOX and 12-LOX activity rather than by hydrolysis of the leukotriene A 4 -epoxide. Exogenous octadeuterated 5 S -HETE and 15 S -HETE were converted to 5,15-diHETE, implicating that multiple oxygenation pathways of arachidonic acid occur in activated leukocytes. The contribution of COX-2 to the biosynthesis of dihydroxylated derivatives of arachidonic acid provides evidence for functional coupling with 5-LOX in activated human leukocytes. Copyright
Preparation of high specific activity tritium-labelled leukotriene B 4 suitable for radioligand binding assay
Schramm, Stanislav I.,Nagaev, Igor Yu.,Sabirsh, Alan,Shevchenko, Valeriy P.,Arkhipova, Anastasiya S.,Haeggstroem, Jesper Z.,Myasoedov, Nikolay F.
, p. 101 - 105 (2008/09/20)
We describe a method of preparation of high specific activity tritium-labelled leukotriene (LT) B4 from [5,6,8,9,11,12, 14,15- 3H] arachidonic acid (AA; 6.66 TBq/mmol) utilizing a LTB 4-synthesizing enzyme system from rat basophilic leukemia (RBL-1) cells. It was shown that both cyclooxygenase inhibitor indomethacin and adenosine 5′-triphosphate induced [3H] AA transformation to [3H] LTB4. In optimized conditions up to 15% of total radioactivity of the incubation mixture was present in [3H] LTB 4. A separation of [3H] LTB4 from other labelled C20:4 products was achieved by a three-step reverse phase-high-performance liquid chromatography in methanol- and acetonitrile-based solvent systems. [3H] LTB4 was confirmed to be identical to the naturally occurring LTB4 by a radioligand binding assay using a culture of HF1 cells that express a BLT1 receptor. Copyright
A General Strategy for the Synthesis of Monohydroxyeicosatetraenoic Acids: Total Synthesis of 5(S)-Hydroxy-6(E),8,11,14(Z)-eicosatetraenoic Acid (5-HETE) and 12(S)-Hydroxy-5,8,14(Z),10(E)-eicosatetraenoic Acid (12-HETE)
Nicolaou, K. C.,Ladduwahetty, T.,Taffer, I. M.,Zipkin, R. E.
, p. 344 - 347 (2007/10/02)
Stereocontrolled total syntheses of 5(S)-hydroxy-6(E),8,11,14(Z)-eicosatetraenoic acid (5-HETE) and 12(S)-hydroxy-5,8,14(Z),10(E)-eicosatetraenoic acid (12-HETE) via palladium(0)-copper(I) coupling technology are described.
