Obajimi Oluwakemi, Black Kenneth D, Glen Iain, Ross Brian M
Scottish Association for Marine Science, Dunstaffnage Marine Laboratory, Oban, Scotland.
Prostaglandins Leukot Essent Fatty Acids. 2007 Feb;76(2):65-71. doi: 10.1016/j.plefa.2006.11.001. Epub 2007 Jan 2.
Omega-3 polyunsaturated fatty acids (PUFA) are increasingly finding use as treatments for a variety of medical conditions. PUFA supplementation can, however, result in increased oxidative stress causing elevated turnover rate of membrane phospholipids, impairment of membrane integrity and increased formation of inflammatory mediators. The aim of this study was to determine which antioxidant compounds were most effective in ameliorating the stimulation of phospholipid turnover by oxidative stress. U937 cells were supplemented with eicosapentaenoic acid and either ascorbic acid, alpha-tocopherol, beta-carotene or astaxanthin prior to being challenged with oxidant. Although all antioxidants were found to be effective in decreasing oxidant-stimulated peroxide formation, only alpha-tocopherol significantly decreased oxidant-stimulated release of 3H-labeled arachidonic acid (AA), while ascorbic acid markedly increased release. All antioxidants except alpha-tocopherol decreased oxidant-stimulated 3H-AA uptake. Our data suggest that antioxidants are not equally effective in combating the effects of oxidative stress upon membrane phospholipid turnover, and that optimal protection will require mixtures of antioxidants.
ω-3多不饱和脂肪酸（PUFA）越来越多地被用于治疗各种医疗状况。然而，补充PUFA会导致氧化应激增加，从而引起膜磷脂周转率升高、膜完整性受损以及炎症介质形成增加。本研究的目的是确定哪些抗氧化化合物在减轻氧化应激对磷脂周转率的刺激方面最有效。在用氧化剂刺激之前，向U937细胞中补充二十碳五烯酸以及抗坏血酸、α-生育酚、β-胡萝卜素或虾青素。尽管发现所有抗氧化剂都能有效减少氧化剂刺激的过氧化物形成，但只有α-生育酚能显著降低氧化剂刺激的3H标记花生四烯酸（AA）的释放，而抗坏血酸则显著增加其释放。除α-生育酚外，所有抗氧化剂都降低了氧化剂刺激的3H-AA摄取。我们的数据表明，抗氧化剂在对抗氧化应激对膜磷脂周转率的影响方面并非同样有效，最佳保护需要抗氧化剂混合物。
