Bassett Chantal M C, McCullough Richelle S, Edel Andrea L, Maddaford Thane G, Dibrov Elena, Blackwood David P, Austria Jose A, Pierce Grant N
Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, Winnipeg, Manitoba, Canada R2H 2A6.
Metabolism. 2009 Dec;58(12):1802-8. doi: 10.1016/j.metabol.2009.06.010. Epub 2009 Jul 23.
Epidemiological evidence has associated dietary trans-fatty acids (TFAs) with coronary heart disease. It is assumed that TFAs stimulate atherosclerosis, but this has not been proven. The purpose of this study was to determine the effects of consuming 2 concentrations of TFAs obtained from commercially hydrogenated vegetable shortening on atherosclerotic development in the presence or absence of elevated dietary cholesterol. Low-density lipoprotein receptor-deficient mice were fed 1 of 7 experimental diets for 14 weeks: low regular fat (LR), low trans-fat (LT), regular high fat, high trans-fat (HT), or a diet containing 2% cholesterol with low regular fat (C + LR), low trans-fat (C + LT), or high trans-fat (C + HT). The extent of lesion development was quantified by en face examination of the dissected aortae. Dietary cholesterol supplementation significantly elevated serum cholesterol levels. Surprisingly, this rise was partially attenuated by the addition of TFAs (C + LT and C + HT) in the diet. Serum triglyceride levels were elevated with the higher-fat diets and with the combination of trans-fat and cholesterol. Animals consuming TFAs in the absence of dietary cholesterol developed a significantly greater extent of aortic atherosclerotic lesions as compared with control animals (LT > LR and HT > regular high fat). Atherosclerotic lesions were more extensive after cholesterol feeding, but the addition of TFAs to this atherogenic diet did not advance atherosclerotic development further. In summary, TFAs are atherogenic on their own; but they do not stimulate further effects beyond the strongly atherogenic effects of dietary cholesterol.
流行病学证据表明，膳食反式脂肪酸（TFA）与冠心病有关。据推测，反式脂肪酸会刺激动脉粥样硬化，但这一点尚未得到证实。本研究的目的是确定食用从商业氢化植物起酥油中获得的两种浓度反式脂肪酸对在膳食胆固醇升高或未升高情况下动脉粥样硬化发展的影响。给低密度脂蛋白受体缺陷小鼠喂食7种实验饮食中的一种，持续14周：低常规脂肪（LR）、低反式脂肪（LT）、常规高脂肪、高反式脂肪（HT），或含2%胆固醇的低常规脂肪饮食（C + LR）、低反式脂肪饮食（C + LT）或高反式脂肪饮食（C + HT）。通过对解剖后的主动脉进行正面检查来量化病变发展程度。膳食补充胆固醇显著提高了血清胆固醇水平。令人惊讶的是，在饮食中添加反式脂肪酸（C + LT和C + HT）可部分减轻这种升高。高脂肪饮食以及反式脂肪与胆固醇的组合会使血清甘油三酯水平升高。与对照动物相比，在无膳食胆固醇情况下食用反式脂肪酸的动物主动脉粥样硬化病变程度显著更高（LT > LR且HT > 常规高脂肪）。喂食胆固醇后动脉粥样硬化病变更广泛，但在这种致动脉粥样硬化饮食中添加反式脂肪酸并未进一步促进动脉粥样硬化发展。总之，反式脂肪酸本身具有致动脉粥样硬化作用；但它们不会在膳食胆固醇的强烈致动脉粥样硬化作用之外产生进一步影响。
