Takase S, Hosoya N
J Nutr Sci Vitaminol (Tokyo). 1986 Apr;32(2):219-27. doi: 10.3177/jnsv.32.219.
This study was conducted to confirm that medium chain triglyceride (MCT) feeding itself would increase hepatic lipogenic enzyme activity without causing a lack of essential fatty acids (EFA) in the liver. Male weaning rats were fed for 11 weeks on diets containing 2% corn oil and 13% various fats: MCT, corn oil, tripalmitin or beef tallow, respectively. MCT feeding was clearly shown to increase the activities of fatty acid synthetase (FAS) and malic enzyme (ME) in the liver. Rats weighing 170 g were pair-fed for 7 days on diets containing 15% MCT, 13% MCT + 2% corn oil, 15% corn oil, and 2% corn oil and no fat (control groups), respectively, under a fixed level of carbohydrate (sucrose). The addition of 2% corn oil to MCT (13%) did not depress these enzyme activities, even though supplementing the fat-free diet with 2% corn oil resulted in a significant decline in the activities. When the rats received various amounts of MCT, the extent to which the degree of FAS and ME activities increased by MCT feeding depended on the amount of MCT in the dietary fat mixture with corn oil. Supplement of over 5% corn oil to MCT diets did not inhibit them sufficiently. In the liver lipids of animals fed MCT, there were no appearances of 20:3 omega 9 (5,8,11-eicosatrienoic acid), but the levels of mono-unsaturated fatty acids were increased by MCT feeding. The results suggest that MCT ingestion itself enhances lipogenic enzyme activity via some metabolic charge.
本研究旨在证实，喂食中链甘油三酯（MCT）本身会增加肝脏中脂肪生成酶的活性，而不会导致肝脏中必需脂肪酸（EFA）缺乏。雄性断奶大鼠分别喂食含2%玉米油和13%各种脂肪（分别为MCT、玉米油、三棕榈酸甘油酯或牛脂）的日粮11周。结果清楚地表明，喂食MCT可增加肝脏中脂肪酸合成酶（FAS）和苹果酸酶（ME）的活性。将体重170 g的大鼠在固定碳水化合物（蔗糖）水平下，分别喂食含15% MCT、13% MCT + 2%玉米油、15%玉米油和2%玉米油且无脂肪（对照组）的日粮7天。向MCT（13%）中添加2%玉米油并不会降低这些酶的活性，尽管在无脂肪日粮中添加2%玉米油会导致酶活性显著下降。当大鼠摄入不同量的MCT时，MCT喂食使FAS和ME活性增加的程度取决于日粮脂肪混合物中MCT与玉米油的含量。向MCT日粮中添加超过5%的玉米油并不能充分抑制它们。在喂食MCT的动物肝脏脂质中，未出现20:3 ω9（5,8,11-二十碳三烯酸），但MCT喂食会增加单不饱和脂肪酸的水平。结果表明，摄入MCT本身通过某种代谢变化增强了脂肪生成酶的活性。
