Centre de Recherche sur la Cognition Animale, UMR CNRS, Université Paul-Sabatier, Toulouse, France.
Biogerontology. 2011 Jun;12(3):185-93. doi: 10.1007/s10522-010-9309-0. Epub 2010 Dec 4.
A cold stress applied to young flies can have positive effects on longevity, behavioral aging, and resistance to heat and infection. However, the same mild stress, if applied at older ages, i.e. in frailer flies, could be a strong stress with negative effects. Cold stress was applied at various ages (weeks 1-2, 2-3, 3-4, and 4-5) and its effect on longevity and on resistance at 6 weeks of age to heat or fungal infection was observed. In males, the cold stress had positive effects on longevity and resistance to infection, except when applied at the oldest age. No positive effect on longevity or resistance to infection was detected in cold-stressed females, as already observed in previous experiments using a cold stress at young age only. By contrast, cold stress applied at various ages increased resistance to heat in both sexes. Therefore, a mild stress can have positive effects on longevity and resistance to strong stresses not only when used at a young age, but also at older ages.
冷应激施加于年轻的果蝇可产生积极影响，延长寿命、减缓行为衰老、增强对热和感染的抵抗力。然而，同样的轻度应激，如果施加于老龄果蝇，即体弱的果蝇，可能是强烈的应激，产生负面效应。冷应激施加于不同的年龄阶段（第 1-2 周、第 2-3 周、第 3-4 周和第 4-5 周），观察其对 6 周龄时的寿命和对热或真菌感染的抵抗力的影响。在雄性中，冷应激对寿命和抗感染能力具有积极影响，除了在最老的年龄阶段施加时。在雌性中，冷应激对寿命或抗感染能力没有积极影响，这与之前仅在年轻时施加冷应激的实验结果一致。相比之下，冷应激施加于不同的年龄阶段增加了两性对热的抵抗力。因此，轻度应激不仅在年轻时使用，而且在老龄时使用，对寿命和对强烈应激的抵抗力都可以产生积极影响。
