Anthony M S, Clarkson T B, Hughes C L, Morgan T M, Burke G L
Comparative Medicine Clinical Research Center, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, NC 27157, USA.
J Nutr. 1996 Jan;126(1):43-50. doi: 10.1093/jn/126.1.43.
Although the beneficial effects of dietary soybean protein compared with animal proteins on plasma lipids, lipoproteins and atherosclerosis have been known for about 50 years, it has been uncertain whether these effects are due to its amino acid concentrations or other components in soybeans. To assess the effect of soybean protein's alcohol-extractable components (including the isoflavonic phytoestrogens genistein and daidzein) on plasma lipid and lipoprotein concentrations and to establish its lack of effect on the reproductive system, we fed 27 peripubertal male and female rhesus monkeys moderately atherogenic diets in which the source of dietary protein was a soy isolate (20% by weight), either containing phytoestrogens (also termed isoflavones) or with the phytoestrogens removed by alcohol extraction. The study was a crossover design with each period lasting for 6 mo. The phytoestrogen-intact soy protein (compared with the alcohol-extracted soy protein) had favorable effects on plasma lipid and lipoprotein concentrations, specifically by significantly reducing LDL+VLDL cholesterol concentrations in both males and females (approximately 30-40% lower), significantly increasing high density lipoprotein cholesterol (HDLC) concentrations for females (approximately 15% higher) and significantly lowering total plasma cholesterol (TPC):HDLC ratios (approximately 20% lower for males and 50% lower for females). The phytoestrogens had no adverse effects on the reproductive systems of either the males or females, as evaluated by reproductive hormone concentrations and organ weights at necropsy. Thus, the isoflavones in soy protein improve cardiovascular disease risk factors without apparent deleterious effects on the reproductive system of peripubertal rhesus monkeys.
尽管与动物蛋白相比，膳食大豆蛋白对血脂、脂蛋白和动脉粥样硬化的有益作用已为人所知约50年，但这些作用是由于其氨基酸浓度还是大豆中的其他成分所致尚不确定。为了评估大豆蛋白的醇提取物成分（包括异黄酮类植物雌激素染料木黄酮和大豆苷元）对血脂和脂蛋白浓度的影响，并确定其对生殖系统无影响，我们给27只青春期前后的雄性和雌性恒河猴喂食中度致动脉粥样化饮食，其中膳食蛋白质来源是大豆分离蛋白（重量占20%），要么含有植物雌激素（也称为异黄酮），要么通过醇提取去除了植物雌激素。该研究采用交叉设计，每个阶段持续6个月。完整植物雌激素的大豆蛋白（与醇提取的大豆蛋白相比）对血脂和脂蛋白浓度有有利影响，具体表现为显著降低雄性和雌性的低密度脂蛋白+极低密度脂蛋白胆固醇浓度（降低约30 - 40%），显著提高雌性的高密度脂蛋白胆固醇（HDLC）浓度（提高约15%），并显著降低总血浆胆固醇（TPC）：HDLC比值（雄性降低约20%，雌性降低约50%）。通过尸检时的生殖激素浓度和器官重量评估，植物雌激素对雄性或雌性的生殖系统均无不良影响。因此，大豆蛋白中的异黄酮可改善心血管疾病风险因素且对青春期前后恒河猴的生殖系统无明显有害影响。
