Kummerow F A, Zhou Q, Mahfouz M M
University of Illinois, Burnsides Research Laboratory, Urbana, IL 61801, USA.
Am J Clin Nutr. 1999 Nov;70(5):832-8. doi: 10.1093/ajcn/70.5.832.
A recent task force of The American Society for Clinical Nutrition and American Society for Nutritional Sciences recommended in a position paper on trans fatty acids that models be developed to assess the effects of changes in fat intake on disease risk.
The objective was to investigate, using human arterial endothelial cells as a model, the influence of trans fatty acids and magnesium on cell membrane composition and on calcium influx into arterial cells, a hallmark of atherosclerosis.
Endothelial cells were cultured for 3 d in media with high (adequate) or low (inadequate) amounts of magnesium plus various concentrations of trans,trans linoelaidic; cis,cis linoleic; trans elaidic; oleic; or stearic acids. The cells were then harvested and the fatty acid composition and the amount of (45)Ca(2+) incorporated into the cell was determined.
The percentage of fatty acids incorporated into the endothelial cells was proportional to the amount added to the culture medium. Adequate magnesium was crucial in preventing calcium influx into endothelial cells. Without an adequate amount of magnesium in the culture medium, linoelaidic and elaidic acids, even at low concentrations, increased the incorporation of (45)Ca(2+) into the cells, whereas stearic acid and oleic acid did not (P < 0.05).
Our model indicated that a diet inadequate in magnesium combined with trans fat may increase the risk of calcification of endothelial cells.
美国临床营养学会和美国营养科学学会的一个特别工作组在一份关于反式脂肪酸的立场文件中建议，应开发模型来评估脂肪摄入量变化对疾病风险的影响。
以人动脉内皮细胞为模型，研究反式脂肪酸和镁对细胞膜组成以及对动脉细胞钙内流（动脉粥样硬化的一个标志）的影响。
将内皮细胞在含有高（充足）或低（不足）量镁以及不同浓度的反式、反式-亚油酸；顺式、顺式-亚油酸；反式-油酸；油酸；或硬脂酸的培养基中培养3天。然后收获细胞，测定脂肪酸组成以及细胞中掺入的（45）Ca（2+）量。
掺入内皮细胞的脂肪酸百分比与添加到培养基中的量成比例。充足的镁对于防止钙流入内皮细胞至关重要。如果培养基中镁含量不足，即使是低浓度的亚油酸和反式油酸也会增加细胞中（45）Ca（2+）的掺入，而硬脂酸和油酸则不会（P < 0.05）。
我们的模型表明，镁含量不足的饮食与反式脂肪相结合可能会增加内皮细胞钙化的风险。
