Targeted disruption of specific steps of the ubiquitin-proteasome pathway by oxidation in lens epithelial cells
Targeted disruption of specific steps of the ubiquitin-proteasome pathway by oxidation in lens epithelial cells
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DOI：
10.1016/s1357-2725(02)00397-7
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发表时间：
2003-05-01
影响因子：
4
通讯作者：
Wagner, BJ
中科院分区：
文献类型：
--
作者：
Hosler, MR;Wang-Su, ST;Wagner, BJ
在氧化应激和衰老模型中，泛素-蛋白酶体途径中的几个步骤已被证明受到抑制。我们在HLE B-3人透镜上皮细胞系中设计了类似的老化和氧化模型。过氧化氢（H2 O2）处理后，B-3细胞表现出预期的c-fos激活。这些相同和相似的处理对透镜蛋白酶体系统的影响是出乎意料的。的2D凝胶图案和糜蛋白酶样活性的20 S核心不受此H2 O2处理，与以前的经验，在其他文化系统。蛋白水解在老化透镜中的关键作用，以及氧化和蛋白酶体变化之间的紧密联系，促使我们进一步模拟透镜氧化，并使用替代剂研究泛素-蛋白酶体途径的几个步骤：巯基特异性氧化剂，二酰胺。20 S核心蛋白酶体、去泛素化和ATP依赖的26 S蛋白酶体活性在联酰胺作用后10 min均出现下降，并在1 h内恢复至接近正常。较高的300 μ M剂量抑制20 S 43%，去泛素化活性17%，26 S 31%。20 S活性和26 S活性的可比敏感性与先前发表的几个模型不同。这种差异可能是组织或细胞系特异性变体的结果，无论是在泛素-蛋白酶体途径的组成部分，或在其修饰细胞内氧化剂或还原剂。(C)2003爱思唯尔科技有限公司版权所有。
Several steps in the ubiquitin-proteasome pathway have been shown to be inhibited in models of oxidative stress and aging. We have designed similar models of aging and oxidation in the HLE B-3 human lens epithelial cell line. Following hydrogen peroxide (H2O2) treatment, B-3 cells exhibited an expected activation of c-fos. The effect of these same and similar treatments on the lens proteasome system was unexpected. The 2D gel pattern and the chymotrypsin-like activity of the 20S core were unaffected by this H2O2 treatment, contrary to previous experience in other culture systems. The critical role of proteolysis in the aging lens, and the strong tie between oxidation and proteasome changes, urged us to further model lens oxidation and investigate several steps of the ubiquitin-proteasome pathway with an alternative agent: the thiol-specific oxidant, diamide. The 20S core proteasome, de-ubiquitinating, and ATP-dependent 26S proteasome activities all showed decreases 10 min after diamide was applied, and recovered to near normal within 1 h. The higher, 300 muM dose inhibited the 20S by 43%, the de-ubiquitinating activity by 17% and the 26S by 31%. The comparable susceptibility of the 20S activity and the 26S activity differs from several previously published models. Such differences may be the result of tissue or cell line-specific variants in either the components of the ubiquitin-proteasome pathway or in their modification by intracellular oxidants or reductants. (C) 2003 Elsevier Science Ltd. All rights reserved.