Ishinaga M, Hamada M, Ohnaka K, Fukunaga K, Minato Y
Department of Food and Nutrition, Hiroshima Women's University, Japan.
Proc Soc Exp Biol Med. 1993 May;203(1):74-7. doi: 10.3181/00379727-203-43575.
A diet containing 15% (w/w) fat and 20% (w/w) of either casein (CAS) or soy protein (SOY) was fed to 4-week-old rats for a period of 18 months. The effects of these dietary proteins on the accumulation of cholesterol and dolichol in livers were studied. After 1 month, the amount of liver cholesterol was about 5 mg/g of liver. After an additional 5 months of feeding, there was a slight decrease in cholesterol per gram of liver (3.6 mg/g of liver in CAS-fed rats and 2.6 mg/g of liver in SOY-fed rats). However, after 18 months, there were a remarkable increase (7.5 mg/g of liver) in CAS-fed rats and only a slight increase in SOY-fed rats. The proportions of liver cholesterol ester in rats fed the CAS diet were 60-70% of the total cholesterol during the experimental period, but in the case of the SOY diet, only rats fed the diet for 1 month showed a high level, 70%, of cholesterol ester. The amounts of liver dolichol in rats fed the CAS and SOY diets after feeding for 18 months were 60 micrograms and 47 micrograms of liver, respectively. There was a 1.5-fold increase in both diets for a period of 18 months. The proportions of liver dolichyl fatty ester in rats fed the CAS diet were 35-40% of the total dolichol during the experimental period, but in the case of the SOY diet, only rats fed the diet for 1 month showed a high level, 36%, of dolichyl fatty ester. The proportions of dolichol ester in rats fed the SOY diet were 25-30% after 6 and 18 months of feeding. These observations indicated that the SOY diet depresses the accumulation of both liver dolichol and cholesterol.
将含有15%（重量/重量）脂肪和20%（重量/重量）酪蛋白（CAS）或大豆蛋白（SOY）的饮食喂养4周龄大鼠18个月。研究了这些膳食蛋白质对肝脏中胆固醇和多萜醇积累的影响。1个月后，肝脏胆固醇含量约为5毫克/克肝脏。再喂养5个月后，每克肝脏中的胆固醇略有下降（CAS喂养的大鼠为3.6毫克/克肝脏，SOY喂养的大鼠为2.6毫克/克肝脏）。然而，18个月后，CAS喂养的大鼠显著增加（7.5毫克/克肝脏），而SOY喂养的大鼠仅略有增加。在实验期间，喂食CAS饮食的大鼠肝脏胆固醇酯的比例占总胆固醇的60 - 70%，但对于SOY饮食，只有喂食该饮食1个月的大鼠胆固醇酯水平较高，为70%。喂食18个月后，喂食CAS和SOY饮食的大鼠肝脏多萜醇含量分别为60微克/克肝脏和47微克/克肝脏。两种饮食在18个月内均增加了1.5倍。在实验期间，喂食CAS饮食的大鼠肝脏多萜醇脂肪酸酯的比例占总多萜醇的35 - 40%，但对于SOY饮食，只有喂食该饮食1个月的大鼠多萜醇脂肪酸酯水平较高，为36%。喂食SOY饮食6个月和18个月后，大鼠多萜醇酯的比例为25 - 30%。这些观察结果表明，SOY饮食可抑制肝脏多萜醇和胆固醇的积累。
