Guimarães A R, Kuga E, Torres R P, Colquhoun A, Curi R, Mancini Filho J
Department of Food Sciences and Experimental Nutrition, Faculty of Pharmaceutical Sciences, Universidade de São Paulo, Brazil.
Biochem Mol Biol Int. 1995 Jun;36(2):451-61.
The composition of the fatty acids in the thymus, spleen and mesenteric lymph nodes was determined in rats fed polyunsaturated (UFC) or saturated (SFC) fatty acid-rich chow during 6 weeks or 14 months. The results indicated that the lipid composition of fatty acids in these tissues was modified by the type of fat given in the diets. Interestingly, the liver did not show any dietary induced change in the composition of fatty acids. The unsaturation index was raised in the lymphoid organs by UFC either after 6 weeks or 14 months. The ageing process itself increased the degree of unsaturation of fatty acids only in the spleen of the 3 groups. A high degree of unsaturation of fatty acids in the tissues may favour the occurrence of lipid peroxidation. It was noteworthy that a linoleic acid-rich diet (UFC) did not change the content of arachidonic acid in the tissues and so would therefore be unlikely to affect eicosanoid synthesis. As shown by previous studies, these fat-rich diets caused marked changes in the key enzyme activities of glucose and glutamine metabolism in the lymphoid organs, by as yet unknown mechanisms. The results reported here suggest that the effect of fat-rich diets on intermediary metabolism does not occur through eicosanoid synthesis and may be a consequence of the lipid peroxidative process or even alterations in the transcription of the enzymes of glycolysis and glutaminolysis.
在6周或14个月期间，给大鼠喂食富含多不饱和脂肪酸（UFC）或饱和脂肪酸（SFC）的食物，然后测定其胸腺、脾脏和肠系膜淋巴结中的脂肪酸组成。结果表明，这些组织中脂肪酸的脂质组成会因饮食中脂肪的类型而改变。有趣的是，肝脏并未显示出任何由饮食引起的脂肪酸组成变化。无论是在6周还是14个月后，UFC都会使淋巴器官中的不饱和指数升高。衰老过程本身仅使三组大鼠脾脏中的脂肪酸不饱和度增加。组织中高度不饱和的脂肪酸可能有利于脂质过氧化的发生。值得注意的是，富含亚油酸的饮食（UFC）不会改变组织中花生四烯酸的含量，因此不太可能影响类花生酸的合成。如先前研究所示，这些富含脂肪的饮食通过尚未明确的机制，导致淋巴器官中葡萄糖和谷氨酰胺代谢的关键酶活性发生显著变化。此处报告的结果表明，富含脂肪的饮食对中间代谢的影响并非通过类花生酸合成发生，可能是脂质过氧化过程的结果，甚至可能是糖酵解和谷氨酰胺分解酶转录改变的结果。
