Ferenac Marina, Polancec Denis, Huzak Miljenko, Pereira-Smith Olivia M, Rubelj Ivica
Department of Molecular Biology, Ruder Bosković Institute, Bijenicka 54, Zagreb 10000, Croatia.
J Gerontol A Biol Sci Med Sci. 2005 Jul;60(7):820-9. doi: 10.1093/gerona/60.7.820.
Most normal mammalian cell lines demonstrate limited growth capacity due to the gradual accumulation of senescent cells in the culture. Senescent cells appear initially at a low incidence, but with increasing frequency as the culture accumulates more divisions. Because it has been suggested that senescence is regulated by telomere shortening in human cells, we compared the telomere lengths of the subpopulation of senescent cells, present in presenescent cultures, with those of young cells. Senescent cells were separated from young cycling cells by either bromodeoxyuridine (BrdU) incorporation followed by Hoechst dye and light treatment or DiI staining followed by separation on a high-speed cell sorter. Our results demonstrate that telomeres of early-senescing cells are the same length, and must shorten at the same rate, as cycling sister cells in the culture. Therefore, senescent cells in young mass cultures occur as a result of a stochastic, nontelomere-dependent process that we have described: sudden senescence syndrome.
由于培养物中衰老细胞的逐渐积累，大多数正常哺乳动物细胞系表现出有限的生长能力。衰老细胞最初出现的频率较低，但随着培养物积累更多的分裂次数，其出现频率会增加。因为有人提出衰老在人类细胞中是由端粒缩短调节的，所以我们比较了衰老前培养物中存在的衰老细胞亚群与年轻细胞的端粒长度。通过溴脱氧尿苷（BrdU）掺入，随后进行Hoechst染料和光照处理，或者通过DiI染色，随后在高速细胞分选仪上进行分离，将衰老细胞与年轻的循环细胞分离。我们的结果表明，早期衰老细胞的端粒长度与培养物中循环的姐妹细胞相同，并且必须以相同的速率缩短。因此，年轻群体培养物中的衰老细胞是我们所描述的随机的、非端粒依赖性过程的结果：突然衰老综合征。
