Baylor College of Medicine, TX 77030, USA.
Exp Gerontol. 2010 Apr;45(4):286-90. doi: 10.1016/j.exger.2009.12.010. Epub 2009 Dec 23.
New blood cells are continually produced from the hematopoietic stem cells (HSCs) that reside in the bone marrow. Throughout the life-span of the organism, this stem cell reservoir sustains life. Although HSCs can persist in vivo longer than one life-span (Harrison et al., 1978), with aging, HSC regenerative potential diminishes and skewing from lymphopoiesis toward myelopoiesis occurs. The expansion in the HSC pool with aging provides sufficient, yet abnormal, blood production. Examination of gene expression changes in aged HSCs has provided a link between aging and genomic instability. Furthermore, studies on the effects of reactive oxygen species (ROS) on HSC aging has given more insight into the reasons for HSC failure. Understanding of the interactions between niche cells and HSCs and changes in them with aging, may give us insights into the lineage skewing phenotype observed in the aged, and also other immune dysfunctions.
新的血细胞不断地从骨髓中造血干细胞(HSCs)产生。在生物的整个生命周期中,这个干细胞库维持着生命。尽管 HSCs 在体内的存活时间可以超过一个生命周期(Harrison 等人,1978),但随着年龄的增长,HSC 的再生潜能会降低,向髓系造血的偏倚发生。随着年龄的增长,HSC 池的扩张提供了足够但异常的血液生成。对衰老 HSCs 中基因表达变化的研究为衰老和基因组不稳定性之间提供了联系。此外,对活性氧(ROS)对 HSC 衰老影响的研究更深入地了解了 HSC 衰竭的原因。了解龛细胞与 HSCs 之间的相互作用及其随年龄的变化,可能使我们深入了解衰老时观察到的谱系偏倚表型,以及其他免疫功能障碍。