Anthony M S, Clarkson T B, Bullock B C, Wagner J D
Comparative Medicine Clinical Research Center, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, NC 27157-1040, USA.
Arterioscler Thromb Vasc Biol. 1997 Nov;17(11):2524-31. doi: 10.1161/01.atv.17.11.2524.
Soy protein, long recognized as having cardiovascular benefits, is a rich source of phytoestrogens (isoflavones). To distinguish the relative contributions of the protein moiety versus the alcohol-extractable phytoestrogens for cardiovascular protection, we studied young male cynomolgus macaques fed a moderately atherogenic diet and randomly assigned to three groups. The groups differed only in the source of dietary protein, which was either casein/lactalbumin (casein, n = 27), soy protein with the phytoestrogens intact (soy+, n = 27), or soy protein with the phytoestrogens mostly extracted (soy-, n = 28). The diets were fed for 14 months. Animals fed soy+ had significantly lower total and LDL plus VLDL cholesterol concentrations compared with the other two groups. They soy+ animals had the highest HDL cholesterol concentrations, the casein group had the lowest, and the soy- group was intermediate. A subset was necropsied for atherosclerosis evaluations (n = 11 per group). Morphometric and angiochemical measures were done to quantify atherosclerosis. Coronary artery atherosclerotic lesions were smallest in the soy+ group (90% less coronary atherosclerosis than the casein group and 50% less than the soy- group), largest in the casein group, and intermediate in the soy- group. The effects of the diets on lesion size and arterial lipid measures of the peripheral arteries were similar to those in the coronary arteries, with greatest prevention of atherogenesis with soy+ and intermediate benefit with soy- relative to casein. We could not determine whether the beneficial effects seen in the soy- group relate to the protein itself or to the remaining traces of phytoestrogens. The beneficial effects of soy protein on atherosclerosis appear to be mediated primarily by the phytoestrogen component. Testicular weights were unaffected by the phytoestrogens.
大豆蛋白长期以来被认为对心血管有益，是植物雌激素（异黄酮）的丰富来源。为了区分蛋白质部分与可醇提取的植物雌激素对心血管保护的相对贡献，我们研究了喂食中度致动脉粥样化饮食的年轻雄性食蟹猴，并将其随机分为三组。三组的区别仅在于膳食蛋白质的来源，分别是酪蛋白/乳白蛋白（酪蛋白组，n = 27）、植物雌激素完整的大豆蛋白（大豆 + 组，n = 27）或植物雌激素大部分被提取的大豆蛋白（大豆 - 组，n = 28）。这些饮食喂养了14个月。与其他两组相比，喂食大豆 + 组的动物总胆固醇以及低密度脂蛋白加极低密度脂蛋白胆固醇浓度显著更低。大豆 + 组动物的高密度脂蛋白胆固醇浓度最高，酪蛋白组最低，大豆 - 组居中。对一部分动物进行了尸检以评估动脉粥样硬化情况（每组n = 11）。通过形态计量学和血管化学测量来量化动脉粥样硬化。大豆 + 组的冠状动脉粥样硬化病变最小（冠状动脉粥样硬化程度比酪蛋白组少90%，比大豆 - 组少50%），酪蛋白组最大，大豆 - 组居中。这些饮食对病变大小和外周动脉脂质指标的影响与冠状动脉相似，大豆 + 组对动脉粥样硬化的预防作用最大，相对于酪蛋白组，大豆 - 组有中等程度的益处。我们无法确定在大豆 - 组中看到的有益效果是与蛋白质本身有关还是与剩余的植物雌激素痕迹有关。大豆蛋白对动脉粥样硬化的有益作用似乎主要由植物雌激素成分介导。睾丸重量不受植物雌激素的影响。
