The mechanisms by which digested fat is absorbed and transported in the circulation are well documented. However, it is uncertain whether the molecular species composition of dietary fats influences the molecular species composition of meal-derived lipids in blood. This may be important because enzymes that remove meal-derived fatty acids from the circulation exhibit differential activities towards individual lipid molecular species. To determine the effect of consuming oils with different molecular compositions on the incorporation of 20:5n-3 and 22:6n-3 into plasma lipid molecular species. Men and women (18-30 years) consumed standardised meals containing 20:5n-5 and 22:6n-3 (total 450 mg) provided by an oil from transgenic Camelina sativa (CSO) or a blended fish oil (BFO) which differed in the composition of 20:5n-3 and 22:6n-3 - containing molecular species. Blood was collected during the subsequent 8 h. Samples were analysed by liquid chromatography-mass spectrometry. The molecular species composition of the test oils was distinct from the composition of plasma triacylglycerol (TG) or phosphatidylcholine (PC) molecular species at baseline and at 1.5 or 6 h after the meal. The rank order by concentration of both plasma PC and TG molecular species at baseline was maintained during the postprandial period. 20:5n-3 and 22:6n-3 were incorporated preferentially into plasma PC compared to plasma TG. Together these findings suggest that the composition of dietary lipids undergoes extensive rearrangement after absorption, such that plasma TG and PC maintain their molecular species composition, which may facilitate lipase activities in blood and/or influence lipoprotein structural stability and function.

中文翻译：

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餐后将 20:5n-3 和 22:6n-3 差异化地掺入人体个体血浆三酰甘油和磷脂酰胆碱分子种类中。


消化的脂肪在循环中被吸收和运输的机制已有详细记录。然而，膳食脂肪的分子种类组成是否影响血液中膳食来源的脂质的分子种类组成尚不确定。这可能很重要，因为从循环中去除膳食衍生脂肪酸的酶对各个脂质分子种类表现出不同的活性。确定食用不同分子组成的油对 20:5n-3 和 22:6n-3 掺入血浆脂质分子种类的影响。男性和女性（18-30 岁）食用含有 20:5n-5 和 22:6n-3（总计 450 毫克）的标准化膳食，这些膳食由转基因亚麻荠油 (CSO) 或混合鱼油 (BFO) 提供，两者不同在含有20:5n-3和22:6n-3的分子种类的组成中。在随后的8小时内采集血液。通过液相色谱-质谱法分析样品。测试油的分子种类组成与基线和餐后 1.5 或 6 小时时血浆三酰甘油 (TG) 或磷脂酰胆碱 (PC) 分子种类的组成不同。餐后期间维持基线时血浆 PC 和 TG 分子种类浓度的排序。与血浆TG相比，20:5n-3和22:6n-3优先掺入血浆PC。这些发现共同表明，膳食脂质的组成在吸收后经历了广泛的重排，使得血浆TG和PC保持其分子种类组成，这可能促进血液中的脂肪酶活性和/或影响脂蛋白结构稳定性和功能。