Kim D N, Schmee J, Lee C S, Eastman A, Ross J S, Thomas W A
Department of Pathology and Laboratory Medicine, Albany Medical College, NY 12208.
Atherosclerosis. 1991 Aug;89(2-3):191-201. doi: 10.1016/0021-9150(91)90060-g.
The addition of a fish oil supplement rich in n - 3 unsaturated fatty acids to a high cholesterol, high saturated fat (BT) diet for swine has been shown previously to result in modest lowering of plasma cholesterol levels and in marked retardation of atherogenesis. It has been suggested that the effect was due to the change in polyunsaturated (PUFA) to saturated fatty acid ratios (P/S) and that a supplement of PUFA of the n - 6 series might have the same effect as the fish oil. We have tested this hypothesis in swine fed an atherogenic diet by comparing the effect of a fish oil supplement producing a P/S ratio of 0.28 to that of corn oil in the same amount producing a ratio of 0.46. The P/S ratio of the atherogenic diet without supplements was 0.16. Thirteen young male Yorkshire swine were fed either BT alone (n = 4), BT + cod liver oil (n = 4) or BT + corn oil (n = 5) for 6 months and then killed for quantitative studies of atherosclerosis in the aortas and coronary arteries including lesion areas, number of lesion cells, and number of monocytes attached to endothelium. Plasma cholesterol levels were determined periodically and lipoproteins were separated terminally by density gradient ultracentrifugation, Pevikon block electrophoresis and immunoelectrophoresis. The fish oil supplement resulted in a 30% reduction in time-weighted average plasma cholesterol levels, and a marked shift in terminal lipoprotein patterns from predominantly apo B and E containing ones to predominantly apo B only ones. Atherogenesis was reduced by the fish oil supplement as judged by several morphometric criteria including size of lesions, number of lesion cells, and number of monocytes attached to lesion endothelium. The corn oil supplement produced no significant reductions in any of these variables from those in swine fed the atherogenic BT diet without the supplement. We conclude that the n - 3 fatty acid rich fish oil supplemented diet retarded atherogenesis, but that this effect was not shared by the corn oil supplemented diet which had an even higher P/S ratio.
先前的研究表明，在猪的高胆固醇、高饱和脂肪（BT）饮食中添加富含n-3不饱和脂肪酸的鱼油补充剂，可适度降低血浆胆固醇水平，并显著延缓动脉粥样硬化的发生。有人认为，这种效果是由于多不饱和脂肪酸（PUFA）与饱和脂肪酸比例（P/S）的变化所致，并且n-6系列的PUFA补充剂可能具有与鱼油相同的效果。我们通过比较产生P/S比为0.28的鱼油补充剂与等量产生比例为0.46的玉米油对喂食致动脉粥样硬化饮食的猪的影响，对这一假设进行了测试。无补充剂的致动脉粥样硬化饮食的P/S比为0.16。13只年轻的雄性约克夏猪分别单独喂食BT（n = 4）、BT + 鱼肝油（n = 4）或BT + 玉米油（n = 5）6个月，然后处死，对主动脉和冠状动脉的动脉粥样硬化进行定量研究，包括病变面积、病变细胞数量和附着在内皮上的单核细胞数量。定期测定血浆胆固醇水平，并在实验结束时通过密度梯度超速离心、Pevikon块电泳和免疫电泳分离脂蛋白。鱼油补充剂使时间加权平均血浆胆固醇水平降低了30%，并且脂蛋白模式在实验结束时从主要含载脂蛋白B和E的模式显著转变为仅主要含载脂蛋白B的模式。根据包括病变大小、病变细胞数量和附着在病变内皮上的单核细胞数量等几个形态学标准判断，鱼油补充剂可减轻动脉粥样硬化的发生。与喂食无补充剂的致动脉粥样硬化BT饮食的猪相比，玉米油补充剂在这些变量中均未产生显著降低。我们得出结论，富含n-3脂肪酸的鱼油补充饮食可延缓动脉粥样硬化的发生，但这种效果并未被具有更高P/S比的玉米油补充饮食所共享。
