title: Oxygenation of 1-docosahexaenoyl lysophosphatidylcholine by lipoxygenases; conjugated hydroperoxydiene and dihydroxytriene derivatives.
abstract: Oxygenation of 1-docosahexaenoyl lysophosphatidylcholine (docosahexaenoyl-lysoPC) by soybean lipoxygenase-1 (LOX-1) or porcine leukocyte LOX was examined. The oxidized products were identified to be hydroperoxydocosahexaenoyl-lysoPC by UV and LC/MS spectrometric analyses. In SP-HPLC and chiral phase-HPLC analyses, the products from the oxygenation of docosahexaenoyl-lysoPC by soybean LOX-1 and porcine leukocyte LOX were found to contain hydroperoxide group mainly at C-17 and C-14, respectively with the S form as a major enantiomer. Next, the sequential exposure of docosahexaenoyl-lysoPC to soybean LOX-1 and porcine leukocyte LOX led to the formation of conjugated triene derivatives possessing a maximal absorption at 271 nm with shoulders at 262 and 281 nm. Based on MS-MS analysis, the conjugated triene derivatives were identified to be 10,17- or 16,17-dihydroxydocosahexaenoyl-lysoPC analogues, suggesting that the diols were produced mainly from hydrolysis of 16,17(S)-epoxide intermediate. In kinetic studies, docosahexaenoyl-lysoPC was more favorable than docosahexaenoic acid as substrate for soybean LOX-1 or leukocyte LOX. Taken together, it is proposed that docosahexaenoyl-lysoPC can be oxygenated as substrates for some lipoxygenases to form conjugated diene and/or triene derivatives.
authors: College of Pharmacy, Chungnam National University, Yuseong-ku, Taejon, 305-764, Korea.
authors: Long Shuang
authors: LS
authors: Huang
authors: Mee Ree
authors: MR
authors: Kim
authors: Dai-Eun
authors: DE
authors: Sok
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004281:Docosahexaenoic Acids / Q000378:metabolism*; D007700:Kinetics; D007962:Leukocytes / Q000201:enzymology; D008084:Lipoxygenase / Q000378:metabolism*; D008244:Lysophosphatidylcholines / Q000378:metabolism*; D010084:Oxidation-Reduction; D013025:Glycine max / Q000201:enzymology; D013379:Substrate Specificity; D013552:Swine; D053719:Tandem Mass Spectrometry
chemical_list: D008244:Lysophosphatidylcholines; C090324:docosahexaenoyl lysophosphatidylcholine; D004281:Docosahexaenoic Acids; D008084:Lipoxygenase