Shaddock J G, Chou M W, Casciano D A
Division of Genetic Toxicology, National Center for Toxicological Research, Jefferson, AR 72079, USA.
Mutagenesis. 1996 May;11(3):281-4. doi: 10.1093/mutage/11.3.281.
The effects of age and caloric restriction on cell proliferation, measured as scheduled DNA synthesis (SDS), were evaluated in primary hepatocyte cultures from control and partially hepatectomized (PH) young to old ad libitum (AL) and caloric-restricted (CR) male Fischer 344 (F344) rats. We reported significant age- or CR-related decreases in SDS in control cultures. PH-induced cultures exhibited significant increases in SDS compared with their control counterparts. Hepatocytes from PH-induced old CR diet-fed animals exhibited significant increases in SDS compared with cultures from control old CR, PH-induced young CR and PH-induced old AL animals. Alternatively, SDS rates for PH-induced young CR animals were significantly lower at 48 h and higher at 72 h than the rates we reported for cultures from PH-induced young AL F344 rats. These data suggest that CR decreases and preserves the proliferative capacity in hepatocytes from young animals and may permit animals to respond more efficiently with induced compensatory cellular replication in old age.
在来自随意进食（AL）和热量限制（CR）的对照及部分肝切除（PH）的年轻到老年雄性Fischer 344（F344）大鼠的原代肝细胞培养物中，评估了年龄和热量限制对以预定DNA合成（SDS）衡量的细胞增殖的影响。我们报告了对照培养物中与年龄或CR相关的SDS显著下降。与对照对应物相比，PH诱导的培养物显示SDS显著增加。与来自对照老年CR、PH诱导的年轻CR和PH诱导的老年AL动物的培养物相比，来自PH诱导的老年CR饮食喂养动物的肝细胞显示SDS显著增加。另外，PH诱导的年轻CR动物在48小时时的SDS速率显著低于我们报道的来自PH诱导的年轻AL F344大鼠培养物的速率，而在72小时时则更高。这些数据表明，CR降低并保留了年轻动物肝细胞的增殖能力，并且可能使动物在老年时对诱导的代偿性细胞复制做出更有效的反应。
