Wilson T A, Behr S R, Nicolosi R J
Department of Health and Clinical Science, Center for Chronic Disease Control, University of Massachusetts Lowell, Lowell, MA 01854, USA.
J Nutr. 1998 Sep;128(9):1429-33. doi: 10.1093/jn/128.9.1429.
The aim of this study was to determine whether the addition of soy protein and guar gum to the American Heart Association (AHA) Step I diet would increase its efficacy compared with the typical "Average American Diet" (AAD) in a non-human primate model. Twenty adult female cynomolgus monkeys (Macaca fascicularis) were fed one of three diets for 6 wk. The AAD contained 36% energy from fat; the standard Step I diet contained 30% energy from fat; and the modified AHA Step I diet contained 30% energy from fat with the addition of soy protein isolate (10% of total energy) and guar gum (5.8 g/d). Plasma samples were collected from food-deprived monkeys at 4, 5 and 6 wk of dietary treatment for analyses of plasma total cholesterol (TC), lipoprotein cholesterol and triacylglycerol (TAG) concentrations. Plasma TC, LDL-C, HDL-C and TAG concentrations were not significantly different in wk 4, 5 and 6 within any of the diet periods; thus the three measurements were averaged. After 6 wk of dietary treatment, monkeys fed the standard Step I diet had lower plasma TC (-19%) (P < 0.05) and LDL cholesterol (LDL-C) (-24%) (P < 0.09) than when they were fed the AAD, with no effect on HDL cholesterol (HDL-C), the lipoprotein cholesterol profile or TAG. Beyond the effect of the standard Step I diet, the modified AHA Step I diet further reduced plasma TC and LDL-C (-24% and -40%) (P < 0. 05) and the TC/HDL-C and LDL-C/HDL-C ratios (-37% and -52%) (P < 0. 05) with no significant changes in plasma HDL-C or TAG. The primary conclusions of this study are that the efficacy of the AHA Step I cholesterol-lowering diet can be increased with the addition of soy protein and guar gum and provide a more favorable lipoprotein cholesterol profile. Whether the cholesterol-lowering effect is the result of soy protein or guar gum or a synergistic effect of both remains to be determined.
本研究的目的是在非人类灵长类动物模型中，确定与典型的“普通美国饮食”（AAD）相比，在美式心脏协会（AHA）第一步饮食中添加大豆蛋白和瓜尔豆胶是否会提高其功效。20只成年雌性食蟹猴（猕猴）被喂食三种饮食之一，为期6周。AAD中36%的能量来自脂肪；标准第一步饮食中30%的能量来自脂肪；改良的AHA第一步饮食中30%的能量来自脂肪，并添加了大豆分离蛋白（占总能量的10%）和瓜尔豆胶（5.8克/天）。在饮食治疗的第4、5和6周，从禁食的猴子身上采集血浆样本，用于分析血浆总胆固醇（TC）、脂蛋白胆固醇和三酰甘油（TAG）浓度。在任何饮食阶段的第4、5和6周，血浆TC、低密度脂蛋白胆固醇（LDL-C）、高密度脂蛋白胆固醇（HDL-C）和TAG浓度均无显著差异；因此，对这三次测量结果进行了平均。经过6周的饮食治疗，与喂食AAD时相比，喂食标准第一步饮食的猴子血浆TC降低了19%（P<0.05），低密度脂蛋白胆固醇（LDL-C）降低了24%（P<0.09），而对高密度脂蛋白胆固醇（HDL-C）、脂蛋白胆固醇谱或TAG没有影响。除了标准第一步饮食的效果外，改良的AHA第一步饮食进一步降低了血浆TC和LDL-C（分别降低24%和40%）（P<0.05）以及TC/HDL-C和LDL-C/HDL-C比值（分别降低37%和52%）（P<0.05），而血浆HDL-C或TAG没有显著变化。本研究的主要结论是，添加大豆蛋白和瓜尔豆胶可以提高AHA第一步降胆固醇饮食的功效，并提供更有利的脂蛋白胆固醇谱。降胆固醇效果是大豆蛋白、瓜尔豆胶的作用还是两者的协同作用，仍有待确定。
