McGee C D, Lieberman P, Greenwood C E
Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Ontario, Canada.
Lipids. 1996 Jun;31(6):611-6. doi: 10.1007/BF02523831.
The fatty acid profile of cardiolipin (CL) from brain and cardiac mitochondria was measured to determine whether CL isolated from these two tissue sources responded similarly to alterations in dietary fat composition. Male Wistar rats were fed 20% (w/w) diets containing 2 to 12% (w/w) 18:2n-6 for four weeks. Despite higher baseline levels of CL 18:2n-6 in cardiac (54 +/- 1% of total fatty acids) compared to brain (13 +/- 1%) mitochondria, CL 18:2n-6 levels increased in proportion to dietary 18:2 levels. The degree of change in 18:2n-6 was comparable with both tissues showing an approximate 1.5- to 2-fold increase. The time course of changes in CL fatty acid profile was examined in a subsequent experiment in which animals were fed 20% (w/w) fat diets containing either 3 or 15% alpha-linoleate. Changes in cardiac CL 18:1, 18:2n-6, and 22:6n-3 levels were observed within one week of feeding. While statistically significant differences were not observed in brain CL until the second week of feeding, the time course did not differ substantively from that observed in heart. The results from this study suggest that while baseline fatty acid profile of cardiac and neural CL differ, mitochondria from both tissues show comparable sensitivity to changes in dietary fat composition. Furthermore, it would appear that the turnover rate of fatty acids in CL is similar in both tissues.
测量了来自脑和心脏线粒体的心磷脂（CL）的脂肪酸谱，以确定从这两种组织来源分离出的CL对饮食脂肪组成变化的反应是否相似。雄性Wistar大鼠喂食含2%至12%（w/w）18:2n-6的20%（w/w）饮食，持续四周。尽管心脏线粒体中CL 18:2n-6的基线水平（占总脂肪酸的54±1%）高于脑线粒体（13±1%），但CL 18:2n-6水平随饮食中18:2水平成比例增加。18:2n-6的变化程度在两种组织中相当，均显示约1.5至2倍的增加。在随后的实验中检查了CL脂肪酸谱变化的时间进程，在该实验中，动物喂食含3%或15%α-亚麻酸的20%（w/w）脂肪饮食。喂食一周内观察到心脏CL 18:1、18:2n-6和22:6n-3水平的变化。虽然直到喂食第二周脑CL中才观察到统计学上的显著差异，但时间进程与心脏中观察到的没有实质性差异。这项研究的结果表明，虽然心脏和神经CL的基线脂肪酸谱不同，但两种组织的线粒体对饮食脂肪组成变化的敏感性相当。此外，似乎CL中脂肪酸的周转率在两种组织中相似。
