Greeley Elizabeth H, Spitznagel Edward, Lawler Dennis F, Kealy Richard D, Segre Mariangela
Department of Pathobiology, University of Illinois, Urbana, IL 61802, USA.
Vet Immunol Immunopathol. 2006 Jun 15;111(3-4):287-99. doi: 10.1016/j.vetimm.2006.02.002. Epub 2006 Mar 29.
Caloric restriction (CR) has been shown to retard immunosenescence and to extend median and maximum life span in rodent species. Longitudinal effects of CR on the canine immune system are presented in this report. A group of 48 Labrador Retrievers, divided at weaning into weight- and sex-matched pairs, were maintained on a diet restriction protocol from age 8 weeks until death. Each restricted dog received 75% of the total food consumed by its control-fed pair mate. Immune parameters were monitored from 4 to 13 years. CR retarded age-related declines in both lymphoproliferative responses and absolute numbers of lymphocytes and the T, CD4, and CD8-cell subsets. In females, CR attenuated the age-related increase in T-cell percentages and marginally retarded the age-related increase in memory cell percentages. Age-related changes in B-cell percentages and numbers were augmented by CR. No direct effect of CR on phagocytic activity of PMN, antibody production or NK cell activity, was observed. Lower lymphoproliferative responses, lower numbers of lymphocytes, T, CD4 and CD8 cells, lower CD8 percentages and higher B-cell percentages were all found to be significantly associated with a decreased likelihood of survival in these dogs.
热量限制（CR）已被证明可延缓免疫衰老，并延长啮齿动物的平均寿命和最长寿命。本报告介绍了CR对犬免疫系统的纵向影响。一组48只拉布拉多猎犬在断奶时按体重和性别匹配成对，从8周龄开始直至死亡，一直遵循饮食限制方案。每只受限制的狗所摄入的食物总量为其对照喂养的配对伙伴的75%。从4岁到13岁监测免疫参数。CR减缓了淋巴细胞增殖反应以及淋巴细胞、T细胞、CD4细胞和CD8细胞亚群的绝对数量与年龄相关的下降。在雌性中，CR减弱了T细胞百分比与年龄相关的增加，并略微减缓了记忆细胞百分比与年龄相关的增加。CR增强了B细胞百分比和数量与年龄相关的变化。未观察到CR对中性粒细胞的吞噬活性、抗体产生或自然杀伤细胞活性有直接影响。较低的淋巴细胞增殖反应、较低的淋巴细胞、T细胞、CD4细胞和CD8细胞数量、较低的CD8百分比以及较高的B细胞百分比均被发现与这些狗存活可能性降低显著相关。
