Chair of Food Chemistry, Faculty of Mathematics and Natural Sciences, University of Wuppertal, Gaussstr. 20, 42119 Wuppertal, Germany.
Institute of Nutritional Sciences, Justus-Liebig-University, Wilhelmstr. 20, 35392 Giessen, Germany.
Food Funct. 2020 Oct 21;11(10):9177-9191. doi: 10.1039/d0fo01462a.
The intake of long-chain n3-polyunsaturated fatty acids (PUFA), which are associated with beneficial health effects, is low in the Western diet, while the portion of dietary n6-PUFA and hence the n6/n3-PUFA ratio is high. Strategies to improve the n3-PUFA status are n3-PUFA supplementation and/or lowering n6-PUFA intake. In the present study, mice were fed with two different sunflower oil-based control diets rich in linoleic (n6-high) or oleic acid (n6-low), either with low n3-PUFA content (∼0.02%) as control or with ∼0.6% eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). The n6-low diet had only little or no effect on levels of arachidonic acid (ARA) and its free oxylipins in liver tissue. Supplementation with EPA or DHA lowered ARA levels with an effect size of n6-high < n6-low. Blood cell %EPA + DHA reached >8% and >11% in n6-high and n6-low groups, respectively. Elevation of EPA levels and EPA derived oxylipins was most pronounced in n6-low groups in liver tissue, while levels of DHA and DHA derived oxylipins were generally unaffected by the background diet. While the n6-low diet alone had no effect on blood and liver tissue ARA levels or n3-PUFA status, a supplementation of EPA or DHA was more effective in combination with an n6-low diet. Thus, supplementation of long-chain n3-PUFA combined with a reduction of dietary n6-PUFA is the most effective way to improve the endogenous n3-PUFA status.
长链 n3-多不饱和脂肪酸（PUFA）的摄入量在西方饮食中较低，而饮食中 n6-PUFA 的比例较高，因此 n6/n3-PUFA 比值较高。改善 n3-PUFA 状况的策略包括 n3-PUFA 补充和/或降低 n6-PUFA 摄入。在本研究中，给小鼠喂食两种不同的葵花油基对照饮食，富含亚油酸（n6-高）或油酸（n6-低），其中一种 n3-PUFA 含量低（约 0.02%）作为对照，另一种含有约 0.6%二十碳五烯酸（EPA）或二十二碳六烯酸（DHA）。n6-低饮食对肝脏组织中花生四烯酸（ARA）及其游离氧代脂类的水平几乎没有影响。补充 EPA 或 DHA 可降低 ARA 水平，n6-高组的作用大小为 n6-低组< n6-高组。n6-高组和 n6-低组的血液细胞 %EPA+DHA 分别达到>8%和>11%。在肝脏组织中，n6-低组中 EPA 水平和 EPA 衍生的氧代脂类升高最为明显，而 DHA 水平和 DHA 衍生的氧代脂类不受背景饮食的影响。尽管 n6-低饮食本身对血液和肝脏组织 ARA 水平或 n3-PUFA 状况没有影响，但 EPA 或 DHA 的补充与 n6-低饮食相结合更为有效。因此，补充长链 n3-PUFA 与减少膳食 n6-PUFA 的联合使用是改善内源性 n3-PUFA 状况的最有效方法。
