Dini L, Rossi L, Marchese E, Ruzittu M T, Rotilio G
Department of Biology, University of Lecce, Italy.
Mech Ageing Dev. 1996 Sep 9;90(1):21-33. doi: 10.1016/0047-6374(96)01748-4.
The present paper reports the effect of aging on receptor mediated endocytosis of Cu, Zn superoxide dismutase in rat liver cells. The fate of bovine Cu, Zn superoxide dismutase conjugated to colloidal gold was followed by electron microscopy in young (2 months) and old (24 months) rats in situ, in vivo and in vitro experiments. The use of different models for the study of the binding and internalization of the enzyme allowed to discriminate the contribution of each different liver cell type. The data obtained demonstrate that aging of the liver affects binding and uptake of this enzyme. In particular both the number of binding sites and the rate of internalization were depressed in old rats. Therefore, the hypothesis of therapeutic application of superoxide dismutase for age-related diseases needs to be revalued in view of the fact that receptor-mediated endocytosis of this protein is a mechanism affected by senescence.
本文报道了衰老对大鼠肝细胞中铜锌超氧化物歧化酶受体介导的内吞作用的影响。通过电子显微镜追踪了在年轻（2个月）和年老（24个月）大鼠体内、原位和体外实验中与胶体金偶联的牛铜锌超氧化物歧化酶的命运。使用不同模型研究该酶的结合和内化作用，有助于区分每种不同肝细胞类型的作用。获得的数据表明肝脏衰老会影响这种酶的结合和摄取。特别是在老年大鼠中，结合位点的数量和内化速率均降低。因此，鉴于该蛋白的受体介导内吞作用是一种受衰老影响的机制，超氧化物歧化酶用于治疗与年龄相关疾病的假设需要重新评估。
