Oxygenation of 1-docosahexaenoyl lysophosphatidylcholine by lipoxygenases; conjugated hydroperoxydiene and dihydroxytriene derivatives

Lipids. 2007 Nov;42(11):981-90. doi: 10.1007/s11745-007-3112-y. Epub 2007 Sep 19.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chromatography, High Pressure Liquid
  • Docosahexaenoic Acids / metabolism*
  • Glycine max / enzymology
  • Kinetics
  • Leukocytes / enzymology
  • Lipoxygenase / metabolism*
  • Lysophosphatidylcholines / metabolism*
  • Oxidation-Reduction
  • Substrate Specificity
  • Swine
  • Tandem Mass Spectrometry

Substances

  • Lysophosphatidylcholines
  • docosahexaenoyl lysophosphatidylcholine
  • Docosahexaenoic Acids
  • Lipoxygenase