De Schrijver R
Laboratory of Nutrition, Catholic University of Leuven, Belgium.
J Nutr. 1990 Dec;120(12):1624-32. doi: 10.1093/jn/120.12.1624.
In two feeding experiments immature (180 g) and mature rats (370 g) were fed a semi-purified diet containing 20% of a protein source (casein, wheat gluten, soybean or potato protein) for 4 wk. Food supply was restricted to 15 g daily. As compared to casein, plant proteins induced significantly lower concentrations of plasma total cholesterol and high density lipoprotein (HDL) cholesterol. The plasma cholesterol increase associated with aging was not prevented by consumption of casein, soybean or potato protein, but wheat gluten seemed to be effective. Lecithin-cholesterol acyltransferase (LCAT) activity was not significantly different in rats of the same age fed different plant proteins, whereas the esterification rate was lower in rats fed casein. With aging the LCAT activity generally decreased. As compared to the casein groups, the rats fed plant proteins showed higher excretion of fecal neutral and acidic steroids. Among the groups fed plant proteins, the fecal output of steroids was variable. Significantly negative correlations were found between fecal total sterol excretion and plasma total cholesterol or HDL cholesterol, respectively. Plant proteins showed a faster migration rate in the stomach, whereas their migration and absorption were slower in the first half of the small intestine. A relation between nonabsorbed nitrogen-containing substances and sterol excretion was hypothesized.
在两项喂养实验中，将未成熟（180克）和成熟大鼠（370克）喂食含20%蛋白质来源（酪蛋白、小麦面筋、大豆或马铃薯蛋白）的半纯化日粮，持续4周。每日食物供应量限制为15克。与酪蛋白相比，植物蛋白诱导的血浆总胆固醇和高密度脂蛋白（HDL）胆固醇浓度显著较低。食用酪蛋白、大豆或马铃薯蛋白并不能阻止与衰老相关的血浆胆固醇升高，但小麦面筋似乎有效。喂食不同植物蛋白的同龄大鼠中，卵磷脂胆固醇酰基转移酶（LCAT）活性无显著差异，而喂食酪蛋白的大鼠酯化率较低。随着衰老，LCAT活性通常会降低。与酪蛋白组相比，喂食植物蛋白的大鼠粪便中性和酸性类固醇排泄量更高。在喂食植物蛋白的组中，类固醇的粪便排出量各不相同。分别在粪便总固醇排泄与血浆总胆固醇或HDL胆固醇之间发现显著的负相关。植物蛋白在胃中的迁移速度更快，而它们在小肠上半部分的迁移和吸收较慢。推测了未吸收含氮物质与固醇排泄之间的关系。
