Tamburini Ilaria, Quartacci Mike F, Izzo Riccardo, Bergamini Ettore
Centro di Ricerca Interdipartimentale "Biologia e Patologia dell'Invecchiamento", Pisa, Italy.
Aging Clin Exp Res. 2004 Dec;16(6):425-31. doi: 10.1007/BF03327396.
Polyunsaturated fatty acids (PUFAs) are essential components of the cell lipid bilayer and are involved in membrane fluidity and normal functioning, but they are vulnerable to free radical attack. Given the role of oxidative stress in the aging process, age-related changes in phospholipid fatty acid (PLFA) composition in rat liver, kidney and heart were assessed in 3-, 12- and 24-month-old rats fed either ad libitum but only every other day, or daily but only 60% of the quantity normally consumed by age-matched controls.
Lipids were extracted and phospholipids (PLs) were separated using the solid phase extraction technique, then transesterified and assayed by gas-liquid chromatography.
Saturated fatty acids (FAs) did not change significantly with age; mono- and bi-unsaturated FAs decreased in the liver and heart, and the ratio of the former to the latter increased in the liver, kidney and heart. PUFAs increased in the liver and heart. As regards individual FAs, 20:1(n-9) decreased in all organs, 14:1 and 18:1(n-7) increased in the kidney and heart, 18:1(n-9) increased in the kidney, 20:2(n-6), 18:2(n-6) and 22:5(n-3) decreased in the liver and heart, 20:3(n-6) decreased in the kidney and increased in the heart. The most abundant PUFAs, 20:4(n-6) and 22:6(n-3), either remained the same or increased with age. The N-9 family increased in the kidney, the N-7 family increased in the kidney and heart, the N-6 family decreased in all three organs, and the N-3 family increased in the liver and kidney. Dietary restriction (DR) significantly counteracted most of these changes, but changes in some FAs [20:2(n-6) in the heart] were magnified by DR and may not be age-related.
Most age-related changes (that occurred in the rat liver, kidney and heart and were counteracted by the two different types of DR) may be involved in the mechanism of aging.
多不饱和脂肪酸（PUFAs）是细胞脂质双层的重要组成部分，参与膜流动性和正常功能，但它们易受自由基攻击。鉴于氧化应激在衰老过程中的作用，本研究评估了3月龄、12月龄和24月龄大鼠肝脏、肾脏和心脏中磷脂脂肪酸（PLFA）组成的年龄相关变化，这些大鼠分别自由采食但隔天一次，或每天采食但仅为年龄匹配对照组正常摄入量的60%。
采用固相萃取技术提取脂质并分离磷脂（PLs），然后进行酯交换反应并通过气液色谱法进行测定。
饱和脂肪酸（FAs）随年龄变化不显著；肝脏和心脏中的单不饱和脂肪酸和多不饱和脂肪酸减少，肝脏、肾脏和心脏中前者与后者的比例增加。肝脏和心脏中的多不饱和脂肪酸增加。就个别脂肪酸而言，所有器官中的20:1(n - 9)减少，肾脏和心脏中的14:1和18:1(n - 7)增加，肾脏中的18:1(n - 9)增加，肝脏和心脏中的20:2(n - 6)、18:2(n - 6)和22:5(n - 3)减少，肾脏中的20:3(n - 6)减少而心脏中的增加。最丰富的多不饱和脂肪酸20:4(n - 6)和22:6(n - 3)要么保持不变，要么随年龄增加。N - 9族在肾脏中增加，N - 7族在肾脏和心脏中增加，N - 6族在所有三个器官中减少，N - 3族在肝脏和肾脏中增加。饮食限制（DR）显著抵消了这些变化中的大部分，但某些脂肪酸（心脏中的20:2(n - 6)）的变化被饮食限制放大，可能与年龄无关。
大多数与年龄相关的变化（发生在大鼠肝脏、肾脏和心脏中，并被两种不同类型的饮食限制所抵消）可能参与衰老机制。
