Herbig Utz, Ferreira Mark, Condel Laura, Carey Dee, Sedivy John M
Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02903, USA.
Science. 2006 Mar 3;311(5765):1257. doi: 10.1126/science.1122446. Epub 2006 Feb 2.
The aging of organisms is characterized by a gradual functional decline of all organ systems. Mammalian somatic cells in culture display a limited proliferative life span, at the end of which they undergo an irreversible cell cycle arrest known as replicative senescence. Whether cellular senescence contributes to organismal aging has been controversial. We investigated telomere dysfunction, a recently discovered biomarker of cellular senescence, and found that the number of senescent fibroblasts increases exponentially in the skin of aging baboons, reaching >15% of all cells in very old individuals. In addition, the same cells contain activated ataxia-telangiectasia mutated kinase and heterochromatinized nuclei, confirming their senescent status.
生物体的衰老特征是所有器官系统功能逐渐衰退。培养中的哺乳动物体细胞具有有限的增殖寿命，在此寿命结束时，它们会经历一种不可逆的细胞周期停滞，即复制性衰老。细胞衰老是否导致生物体衰老一直存在争议。我们研究了端粒功能障碍，这是一种最近发现的细胞衰老生物标志物，发现衰老狒狒皮肤中衰老成纤维细胞的数量呈指数增长，在非常年老的个体中达到所有细胞的15%以上。此外，这些相同的细胞含有活化的共济失调毛细血管扩张突变激酶和异染色质化的细胞核，证实了它们的衰老状态。
