Huang Long Shuang, Kim Mee Ree, Sok Dai-Eun
College of Pharmacy, Chungnam National University, Yuseong-ku, Taejon, 305-764, Korea.
Lipids. 2007 Nov;42(11):981-90. doi: 10.1007/s11745-007-3112-y. Epub 2007 Sep 19.
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.
研究了大豆脂氧合酶-1（LOX-1）或猪白细胞脂氧合酶对1-二十二碳六烯酰溶血磷脂酰胆碱（二十二碳六烯酰-溶血PC）的氧化作用。通过紫外和液相色谱/质谱光谱分析，确定氧化产物为氢过氧化二十二碳六烯酰-溶血PC。在反相高效液相色谱和手性相高效液相色谱分析中，发现大豆LOX-1和猪白细胞脂氧合酶氧化二十二碳六烯酰-溶血PC产生的产物中，氢过氧化物基团主要分别位于C-17和C-14，且S型为主要对映体。接下来，将二十二碳六烯酰-溶血PC依次暴露于大豆LOX-1和猪白细胞脂氧合酶下，导致形成共轭三烯衍生物，其在271 nm处有最大吸收峰，在262和281 nm处有肩峰。基于串联质谱分析，确定共轭三烯衍生物为10,17-或16,17-二羟基二十二碳六烯酰-溶血PC类似物，这表明二醇主要由16,17(S)-环氧化物中间体水解产生。在动力学研究中，二十二碳六烯酰-溶血PC作为大豆LOX-1或白细胞脂氧合酶的底物比二十二碳六烯酸更有利。综上所述，提出二十二碳六烯酰-溶血PC可作为某些脂氧合酶的底物被氧化，形成共轭二烯和/或三烯衍生物。
