关节软骨细胞的DNA修复。I. 单层培养中紫外线照射后的非预定DNA合成。

DNA repair by articular chondrocytes. I. Unscheduled DNA synthesis following ultraviolet irradiation in monolayer culture.

作者信息

Krystal G, Morris G M, Lipman J M, Sokoloff L

出版信息

Mech Ageing Dev. 1983 Jan;21(1):83-96. doi: 10.1016/0047-6374(83)90018-0.

Abstract

The hypothesis that aging of articular chondrocytes at a cellular level results from loss of DNA repair capability was studied by measuring unscheduled DNA synthesis (UDS). Cultured rabbit and human articular chondrocytes were irradiated with 254 nm ultraviolet light (20 J/m2) following treatment with 10 mM hydroxyurea. Neither the "in vitro senescence" nor spontaneous transformation that developed during serial passage of rabbit chondrocytes was accompanied by diminution of UDS. Synthesis of sulfated glycosaminoglycans declined more rapidly than the ability of the cells to divide. Levels of UDS by chondrocytes from old donors, rabbit or human, were comparable to those of younger individuals. UDS was greater in human than rabbit chondrocytes. Similar data have been reported previously for dermal fibroblasts but do not necessarily indicate that there is a direct or causative relationship between UDS capability and the longevity of mammalian species. X-Irradiation of rabbit chondrocytes or cartilage explants, in doses up to 40 000 rads, yielded no measurable UDS.

摘要

通过测量非预定DNA合成（UDS），研究了关节软骨细胞在细胞水平上的衰老是否源于DNA修复能力丧失这一假说。用10 mM羟基脲处理后，将培养的兔和人关节软骨细胞用254 nm紫外线（20 J/m2）照射。在兔软骨细胞连续传代过程中出现的“体外衰老”和自发转化，均未伴有UDS的减少。硫酸化糖胺聚糖的合成比细胞分裂能力下降得更快。来自老年供体（兔或人）的软骨细胞的UDS水平与年轻个体相当。人软骨细胞的UDS高于兔软骨细胞。先前已报道真皮成纤维细胞有类似数据，但这不一定表明UDS能力与哺乳动物物种的寿命之间存在直接或因果关系。对兔软骨细胞或软骨外植体进行高达40000拉德的X射线照射，未产生可测量的UDS。