摘要
以体外培养的不同代龄的人胚肺二倍体成纤维细胞（２ Ｂ Ｓ）为对象，紫外线诱导 Ｄ Ｎ Ａ 损伤后，观察细胞形态、增殖特性、细胞周期、 Ｄ Ｎ Ａ 修复变化等细胞应答以及 ｇａｄｄ１５３、ｐ２１ Ｗ Ａ Ｆ１／ Ｃ Ｉ Ｐ１／ Ｓ Ｄ Ｉ１、ｐ５３ 等基因的转录水平的表达变化．结果显示：紫外线诱导 Ｄ Ｎ Ａ 损伤后，衰老（＞ ５５ 代）２ Ｂ Ｓ细胞形态及增殖能力的改变不如年轻细胞（＜ ３０ 代）显著；不同代龄的细胞损伤后均出现 Ｇ１ 期阻滞现象，年轻细胞 Ｇ１ 期阻滞率明显高于衰老细胞（ Ｐ＜ ００５）；衰老细胞总的修复能力较年轻细胞明显下降（ Ｐ＜ ００１）；同时，ｇａｄｄ１５３、ｐ２１、ｐ５３ 等的可诱导性均低于年轻 ２ Ｂ Ｓ细胞．由此，分别在细胞水平与基因水平反映了衰老细胞经紫外线照射损伤后的细胞应答变化与修复机能减退的关系．
The DNA damaged cellular model was established by human diploid fibroblast (2BS) cells at different passages after UV irradiation.The cellular responses,such as,morphology,replication,cell cycle and DNA repair,were investigated.The changes of the expressions of transcription level of p21,p53 and gadd153 genes were also measured.The results showed that the changes of morphology and growth ability in senescent cells were not as significant as those in young cells.The increase of G1 arrest in senescent cells was not so obvious as that in the young cells after UV irradiation although the senescnt cells were also arrested in G1 phase.The DNA repair capacity of senescent 2BS cells significantly declined as compared with that of the young ones ( P <0.01).At the same time,the inducibility of gadd153,p21,and p53 genes in senescent cells declined as compared with that in the young cells.All these results suggest the relationship among the changes of the cellular response to DNA damage,the changes of checkpoint control in senescent cells and the decline of the repair capacity of the senescent cells in cellular and gene levels.
出处
《中国生物化学与分子生物学报》
CAS
CSCD
1999年第4期646-650,共5页
Chinese Journal of Biochemistry and Molecular Biology
基金
国家自然科学基金
