Tacconi M T, Lligoña L, Salmona M, Pitsikas N, Algeri S
Istituto di Ricerche Farmacologiche Mario Negri, Milano, Italy.
Neurobiol Aging. 1991 Jan-Feb;12(1):55-9. doi: 10.1016/0197-4580(91)90039-m.
In experimental animals dietary restriction reduces the body weight increase due to aging, increases longevity and delays the onset of age-related physiological deterioration, including age-related changes in serum lipids. Little is known about the influence of food restriction on brain lipids, whose concentration and composition have been shown to change with age. We studied whether some biochemical and biophysical parameters of rat brain membranes, known to be modified with age, were affected by a diet low in calories, in which 50% of lipids and 35% of carbohydrates have been replaced by fibers. The diet was started at weaning and maintained throughout the animal's entire life span. Animals fed the low calorie diet survived longer and gained less body weight than standard diet fed rats. Age-related increases in microviscosity, cholesterol/phospholipid and sphingomyelin/phosphatidylcholine ratios were reduced or restored to the levels of young animals in cortex membranes of 32 old rats fed the low calorie diet, while the age-related increase in mono- to polyunsaturated fatty acid ratios in phospholipids was further raised. In conclusion we have shown that a diet low in calories and high in fibers affects lipid composition in the rat brain, in a direction opposite to that normally believed to reduce age-related deterioration of brain functions.
在实验动物中，饮食限制可减少因衰老导致的体重增加，延长寿命，并延缓与年龄相关的生理衰退的发生，包括血清脂质的年龄相关变化。关于食物限制对脑脂质的影响知之甚少，而脑脂质的浓度和组成已被证明会随年龄变化。我们研究了大鼠脑膜的一些已知会随年龄改变的生化和生物物理参数是否会受到低热量饮食的影响，在这种饮食中，50%的脂质和35%的碳水化合物被纤维所替代。该饮食从断奶开始并在动物的整个生命周期中持续维持。与喂食标准饮食的大鼠相比，喂食低热量饮食的动物存活时间更长，体重增加更少。在32只喂食低热量饮食的老年大鼠的皮质膜中，与年龄相关的微粘度、胆固醇/磷脂和鞘磷脂/磷脂酰胆碱比率的增加有所减少或恢复到幼年动物的水平，而磷脂中单不饱和脂肪酸与多不饱和脂肪酸比率的与年龄相关的增加则进一步升高。总之，我们已经表明，低热量高纤维饮食会影响大鼠脑内的脂质组成，其影响方向与通常认为的可减少与年龄相关的脑功能衰退的方向相反。
