Department of Food Science, Aarhus University, Tjele/Årslev, Denmark.
Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark.
Mol Nutr Food Res. 2017 Dec;61(12). doi: 10.1002/mnfr.201601048. Epub 2017 Nov 3.
The aim of the paper is to investigate whether changes in the metabolome could explain observed changes in body composition in overweight adults after consumption of butter with high level of medium-chain fatty acids (MCFAs) in combination with casein or whey.
With GC-TOF and LC-Q/MS, metabolites in plasma and urine from a 12-week randomized double-blinded human intervention including 52-abdominally overweight adults were analyzed. The participants consumed 63 g per day of milk fat (high or low in MCFAs) and 60 g per day of protein (whey or casein). Urinary loss of the tricarboxylic acid cycle metabolites and a concomitantly increase of glycerol in blood were observed in the whey + high-MCFAs group, indicating potential lower anabolic processes, such as lipogenesis, by draining substrates. High intake of MCFAs resulted in elevated level of urinary adipic (independently of protein type) and plasma sebacic acid (with whey), indicating a potential increase in oxidation of MCFAs, which might lead to energy loss.
The type of protein showed highest effect on the overall metabolic profiles, but ω-oxidation of MCFAs in the liver seemed to be the main reason for the observed reduction in body fat mass after consumption of high MCFAs, independent of type of protein.
本文旨在研究在超重成年人中，食用富含中链脂肪酸（MCFAs）的黄油与酪蛋白或乳清蛋白结合后，代谢组的变化是否可以解释其身体成分的变化。
通过 GC-TOF 和 LC-Q/MS 分析了为期 12 周的随机双盲人体干预研究中 52 名腹部超重成年人的血浆和尿液中的代谢物。参与者每天摄入 63 克牛奶脂肪（MCFAs 含量高或低）和 60 克蛋白质（乳清蛋白或酪蛋白）。乳清蛋白+高 MCFAs 组观察到三羧酸循环代谢物在尿液中的丢失和血液中甘油的同时增加，表明潜在的较低的合成代谢过程，如脂肪生成，通过消耗底物。MCFAs 的高摄入量导致尿液中戊二酸（与蛋白质类型无关）和血浆中癸二酸（与乳清蛋白有关）水平升高，表明 MCFAs 的ω-氧化增加，这可能导致能量损失。
蛋白质的类型对整体代谢谱的影响最大，但肝脏中 MCFAs 的ω-氧化似乎是食用高 MCFAs 后体脂减少的主要原因，与蛋白质类型无关。
