Ruckenstuhl Christoph, Carmona-Gutierrez Didac, Madeo Frank
Institute of Molecular Biosciences, University of Graz, Austria.
Aging (Albany NY). 2010 Oct;2(10):643-9. doi: 10.18632/aging.100223.
As time goes by, a postmitotic cell ages following a degeneration process ultimately ending in cell death. This phenomenon is evolutionary conserved and present in unicellular eukaryotes as well, making the yeast chronological aging system an appreciated model. Here, single cells die in a programmed fashion (both by apoptosis and necrosis) for the benefit of the whole population. Besides its meaning for aging and cell death research, age-induced programmed cell death represents the first experimental proof for the so-called group selection theory: Apoptotic genes became selected during evolution because of the benefits they might render to the whole cell culture and not to the individual cell. Many anti‐aging stimuli have been discovered in the yeast chronological aging system and have afterwards been confirmed in higher cells or organisms. New work from the Burhans group (this issue) now demonstrates that glucose signaling has a progeriatric effect on chronologically aged yeast cells: Glucose administration results in a diminished efficacy of cells to enter quiescence, finally causing superoxide‐mediated replication stress and apoptosis.
随着时间的推移，有丝分裂后的细胞会经历一个退化过程，最终导致细胞死亡，从而走向衰老。这种现象在进化过程中是保守的，在单细胞真核生物中也存在，这使得酵母的时序性衰老系统成为一个备受青睐的模型。在这里，单个细胞以程序性方式死亡（通过凋亡和坏死），以造福整个群体。除了对衰老和细胞死亡研究的意义外，年龄诱导的程序性细胞死亡代表了所谓群体选择理论的首个实验证据：凋亡基因在进化过程中被选择，是因为它们可能给整个细胞培养物带来益处，而不是给单个细胞带来益处。在酵母时序性衰老系统中发现了许多抗衰老刺激因素，随后在高等细胞或生物体中得到了证实。Burhans团队的新研究（本期）表明，葡萄糖信号对时序性衰老的酵母细胞具有促衰老作用：给予葡萄糖会导致细胞进入静止期的效率降低，最终导致超氧化物介导的复制应激和凋亡。
