Goodrick C L, Ingram D K, Reynolds M A, Freeman J R, Cider N
Nathan W. Shock Laboratories, Gerontology Research Center, Baltimore, MD 21224.
Mech Ageing Dev. 1990 Jul;55(1):69-87. doi: 10.1016/0047-6374(90)90107-q.
Beginning at either 1.5, 6 or 10 months of age, male mice from the A/J and C57BL/6J strains and their F1 hybrid, B6AF1/J were fed a diet (4.2 kcal/g) either ad libitum every day or in a restricted fashion by ad libitum feeding every other day. Relative to estimates for ad libitum controls, the body weights of the intermittently-fed restricted C57BL/6J and hybrid mice were reduced and mean and maximum life span were incremented when the every-other-day regimen was initiated at 1.5 or 6 months of age. When every-other-day feeding was introduced at 10 months of age, again both these genotypes lost body weight relative to controls; however, mean life span was not significantly affected although maximum life span was increased. Among A/J mice, intermittent feeding did not reduce body weight relative to ad libitum controls when introduced at 1.5 or 10 months of age; however, this treatment did increase mean and maximum life span when begun at 1.5 months, while it decreased mean and maximum life span when begun at 10 months. When restricted feeding was introduced to this genotype at 6 months of age, body weight reduction compared to control values was apparent at some ages, but the treatment had no significant effects on mean or maximum life span. These results illustrate that the effects of particular regimens of dietary restriction on body weight and life span are greatly dependent upon the genotype and age of initiation. Moreover, when examining the relationship of body weight to life span both between and within the various groups, it was clear that the complexity of this relationship made it difficult to predict that lower body weight would induce life span increment.
从1.5个月、6个月或10个月大开始，将A/J和C57BL/6J品系的雄性小鼠及其F1杂种B6AF1/J分为两组，一组每天随意进食一种日粮（4.2千卡/克），另一组隔天随意进食，即采取限制进食方式。与随意进食的对照组相比，当1.5个月或6个月大开始隔天进食的限制进食方案时，C57BL/6J品系和杂种小鼠的体重减轻，平均寿命和最长寿命增加。当10个月大开始隔天进食时，这两种基因型的小鼠体重相对于对照组再次减轻；然而，平均寿命没有受到显著影响，尽管最长寿命有所增加。在A/J品系小鼠中，1.5个月或10个月大开始隔天进食时，相对于随意进食的对照组，体重并未减轻；然而，1.5个月大开始这种处理时，平均寿命和最长寿命增加，而10个月大开始时则降低。当6个月大对该基因型小鼠开始限制进食时，在某些年龄段与对照值相比体重减轻明显，但该处理对平均寿命或最长寿命没有显著影响。这些结果表明，特定的饮食限制方案对体重和寿命的影响很大程度上取决于基因型和开始实施的年龄。此外，在研究不同组之间以及组内体重与寿命的关系时，很明显这种关系的复杂性使得很难预测较低的体重会导致寿命延长。
