CELL RENEWAL, SIZE, AND CLONING AS BIOMARKERS OF AGING

这个项目的主要目标是确定细胞周转率和 细胞大小是小鼠衰老的可靠生物标志。正常老化 小鼠、热量缺乏(CD)小鼠和转基因小鼠 异位表达生长激素(GH)将被测试。这个 生物标志物将被划分为对牺牲的致命性确定 动物和一套非致命性测试将被用来预测 每只小鼠的寿命。要测试的小鼠(3-，12-， 21个月和30个月大的动物)将从NIA接收 老龄研究繁育群体(GH小鼠除外)。 预计生物标志物指数将与年龄相关 而任何与年龄相关的变化都应该减慢 在长寿的CD小鼠中。生长激素小鼠似乎在衰老 比它们的控件更快一些，因此提供了 生物标志物系统的有趣测试。 将进行单元格周转和体积的测定 无论是在体内还是体外： 体内--4个年龄组的对照组和CD小鼠分别输注1 或用BrdU皮下微渗泵给药4周。在… 这段时间结束时，细胞在几个器官中的周转情况 已知的高有丝分裂率和低有丝分裂率将被确定。 将通过过氧化物酶核染色法进行测定- 标记BrdU抗血清和自动图像分析计数， 允许快速处理计数。帮手和 外周血中的抑制性T细胞和B细胞 确定细胞周期的数量和历史 激光激活的细胞分选机和特定的抗血清。 在体外--来自细胞所在组织的细胞群 将分散体放入培养物中进行克隆测定 真皮、主动脉各细胞样本的大小分布 平滑肌和骨髓成纤维细胞。的细胞体积。 分离的细胞也将在FACS分析仪上确定。 只有经Hoechst 33342染色为二倍体的活细胞才能 包括在体积分析中。

The main goal of this project is to determine if cell turnover and cell size are reliable biomarkers of aging in mice. Normal aging mice, calorically deprived (CD) mice, and transgenic mice ectopically expressing growth hormone (GH) will be tested. The biomarkers will be divided into lethal determinations on sacrificed animals and a set of nonlethal tests that will be used to predict the longevity of individual mice. The mice to be tested (3-, 12-, 21-, and 30-month-old animals) will be received from the NIA aging study breeding colony (with the exception of the GH mice). The biomarker indices would be expected to correlate to the age of the control mice, and any age-related changes should be slowed in the long-lived CD mice. The GH mice appear to be aging somewhat more rapidly than their controls and thus offer an interesting test of the biomarkers system. Determinations of cell turnover and volume will be carried out both in vivo and in vitro: In vivo--Control and CD mice of 4 age groups will be infused for 1 or 4 weeks with BrdU via subcutaneous osmotic minipumps. At the end of this time, the present of cell turnover in several organs of known high and low mitotic rates will be determined. Determination will be made by nuclear staining with a peroxidase- tagged BrdU antiserum and automated image analysis counting, allowing the rapid processing of counts. The helper and suppressor T cells and the B cells of peripheral blood will be determined for number and history of cell cycling with the aid of a laser-activated cell sorter and specific antisera. In vitro-- Cell populations from those tissues in which cells are dispersible will be placed in culture for determination of clone size distribution for each sample of cells from dermal skin, aortic smooth muscle, and bone marrow fibroblasts. The cell volume of the dissociated cell will also be determined on a FACS analyzer. Only viable cells which stain as diploid with Hoechst 33342 will be included in the volume analysis.