Wilson T A, Meservey C M, Nicolosi R J
Center for Chronic Disease Control, Department of Health and Clinical Science, University of Massachusetts Lowell, 01854, USA.
Atherosclerosis. 1998 Sep;140(1):147-53. doi: 10.1016/s0021-9150(98)00132-4.
The current study was designed to investigate the hypocholesterolemic and anti-atherogenic properties of soy lecithin beyond its fatty acid content. In experiment 1, 18 cynomolgus monkeys were divided into three groups of six and fed diets which approximated either the average American diet (AAD), the American Heart Association (AHA) Step I diet, or a modified AHA (mAHA) Step I diet containing 3.4% soy lecithin for 8 weeks. Plasma samples were collected from food-deprived monkeys and analyzed for total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), very low- and low-density lipoprotein cholesterol (non-HDL-C), and triglyceride (TG) concentrations. Group comparisons revealed that monkeys fed the mAHA Step 1 diet had significantly lower plasma TC (-46%) and non-HDL-C (-55%) levels compared to the AAD diet, whereas monkeys fed the AHA Step 1 diet had lesser reductions in plasma TC (-21%) and non-HDL-C (-18%) levels. The monkeys fed the mAHA Step I diet had significantly lower plasma TC (-32%) and non-HDL-C (-45%) compared to the monkeys fed the AHA step diet. Also, only the mAHA Step I diet significantly reduced pre-treatment plasma TC and non-HDL-C levels by - 39 and -51% respectively with no significant effect on plasma HDL-C or TG levels. In experiment 2, 45 hamsters were divided into three groups of 15 and fed the following three modified non-purified diets for 8 weeks: a hypercholesterolemic diet (HCD) containing 10%, coconut oil and 0.05%, cholesterol, HCD plus 3.4%, soy lecithin (+SL), or the HCD with added levels of linoleate and choline equivalent to the +SL diet but no lecithin (-SL). Plasma lipids were determined as in experiment 1 and aortas were perfusion-fixed and Oil Red O stained for morphometric analyses of fatty streak area. Relative to the HCD group, the +SL-treated hamsters had significantly lower plasma TC (-58%), non-HDL-C (-73%) and aortic fatty streak area (-90%). Relative to the -SL group, hamsters fed the +SL diet had significantly lower plasma TC (-33%), non-HDL-C (-50%) and significantly reduced aortic fatty streak area (-79%). In conclusion, the first experiment suggests that the cholesterol-lowering efficacy of the AHA Step I diet can be enhanced with the addition of soy lecithin without reducing plasma HDL-C levels. whereas the second experiment suggest that the hypocholesterolemic, and in particular, the anti-atherogenic properties of soy lecithin cannot be attributed solely to its linoleate content.
本研究旨在探究大豆卵磷脂除脂肪酸含量之外的降胆固醇和抗动脉粥样硬化特性。在实验1中，18只食蟹猴被分为三组，每组6只，分别喂食近似美国平均饮食（AAD）、美国心脏协会（AHA）第一步饮食或含3.4%大豆卵磷脂的改良AHA（mAHA）第一步饮食，为期8周。从禁食的猴子身上采集血浆样本，分析总胆固醇（TC）、高密度脂蛋白胆固醇（HDL-C）、极低密度和低密度脂蛋白胆固醇（非HDL-C）以及甘油三酯（TG）浓度。组间比较显示，与AAD饮食组相比，喂食mAHA第一步饮食的猴子血浆TC（-46%）和非HDL-C（-55%）水平显著降低，而喂食AHA第一步饮食的猴子血浆TC（-21%）和非HDL-C（-18%）水平降低幅度较小。与喂食AHA第一步饮食的猴子相比，喂食mAHA第一步饮食的猴子血浆TC（-32%）和非HDL-C（-45%）显著降低。此外，只有mAHA第一步饮食能使治疗前血浆TC和非HDL-C水平分别显著降低39%和51%，而对血浆HDL-C或TG水平无显著影响。在实验2中，45只仓鼠被分为三组，每组15只，喂食以下三种改良非纯化饮食，为期8周：含10%椰子油和0.05%胆固醇的高胆固醇饮食（HCD）、HCD加3.4%大豆卵磷脂（+SL）或添加相当于+SL饮食中水平的亚油酸和胆碱但不含卵磷脂的HCD（-SL）。如实验1那样测定血浆脂质，并对主动脉进行灌注固定，用油红O染色以对脂肪条纹面积进行形态计量分析。相对于HCD组，+SL处理的仓鼠血浆TC（-58%）、非HDL-C（-73%）和主动脉脂肪条纹面积（-90%）显著降低。相对于-SL组，喂食+SL饮食的仓鼠血浆TC（-33%）、非HDL-C（-50%）显著降低，主动脉脂肪条纹面积显著减少（-79%）。总之，第一个实验表明，添加大豆卵磷脂可增强AHA第一步饮食的降胆固醇功效，且不降低血浆HDL-C水平。而第二个实验表明，大豆卵磷脂的降胆固醇特性，尤其是抗动脉粥样硬化特性不能仅归因于其亚油酸含量。
