Lu M H, Hinson W G, Turturro A, Anson J, Hart R W
Food and Drug Administration, National Center for Toxicological Research, Jefferson, Arkansas 72079.
Mech Ageing Dev. 1991 Jun 14;59(1-2):111-21. doi: 10.1016/0047-6374(91)90077-d.
The effect of dietary restriction (DR) on the proportion of cells in various phases of the cell cycle as determined by flow cytometry was investigated in the bone marrow and kidney of young and old Fischer 344 rats. Control rats were fed a standard occurrence of numerous age-associated diseases, including cancer, renal diseases and by the control rats starting at 16 weeks of age until killed at 5 or 20 months old. The relative proportion of cells in the various phases of the cell cycle was independent of tissue type, treatment condition and age, consistently showing an order of G1- greater than S- greater than G2M-phase. In old rats DR did not affect cell cycling in bone marrow of either sex, however, it did cause an increase in the percentage of G1-phase cells in the kidney of male rats. Additionally, DR caused a mathematically significant change in the percentage of cells in all phases of the cell cycle in the bone marrow of young male rats but had no effect in young females. The percentage of S-phase cells in both tissues of both sexes decreased in old rats when compared to young rats regardless of treatment conditions, indicating a parallel decline in cell proliferating activity with aging. To summarize, DR produces a greater cell cycle effect in the young male than the old male rats. Proliferative capacity is enhanced when the young male rats are dietary restricted. This may aid in DNA repair mechanisms and/or immune system response.
在年轻和老年Fischer 344大鼠的骨髓和肾脏中，研究了饮食限制（DR）对通过流式细胞术测定的细胞周期各阶段细胞比例的影响。对照大鼠从16周龄开始喂食标准饮食，直至5或20月龄处死，在此期间出现了许多与年龄相关的疾病，包括癌症、肾脏疾病等。细胞周期各阶段细胞的相对比例与组织类型、治疗条件和年龄无关，始终呈现G1期＞S期＞G2M期的顺序。在老年大鼠中，DR对两性骨髓中的细胞周期没有影响，然而，它确实导致雄性大鼠肾脏中G1期细胞的百分比增加。此外，DR使年轻雄性大鼠骨髓中细胞周期所有阶段的细胞百分比发生了数学上显著的变化，但对年轻雌性大鼠没有影响。无论治疗条件如何，与年轻大鼠相比，老年大鼠两性两种组织中S期细胞的百分比均下降，这表明细胞增殖活性随衰老而平行下降。总之，DR对年轻雄性大鼠产生的细胞周期效应大于老年雄性大鼠。当年轻雄性大鼠饮食受限时，其增殖能力增强。这可能有助于DNA修复机制和/或免疫系统反应。
