Mitochondrial proteomic alterations caused by long-term low-dose copper exposure in mouse cortex

作者：Lin, Xuemei; Wei, Gang; Huang, Zhijun; Qu, Zhongsen; Huang, Xinfeng; Xu, Hua^*; Liu, Jianjun; Zhuang, Zhixiong; Yang, Xifei^*

来源：Toxicology Letters, 2016, 263: 16-25.

DOI：10.1016/j.toxlet.2016.10.009

• Proteomics
• Mitochondria
• Copper
• Neurotoxicity

Mitochondrial dysfunction is involved in neurotoxicity caused by exposure of various chemicals such as copper. However, the effects of long-term low-dose copper exposure on mitochondrial proteome remain unclear. In this study, we found the treatment of copper (0.13 ppm copper sulfate in drinking water) for 12 months caused abnormal expression of a total of 13 mitochondrial proteins (7 up-regulated and 6 downregulated) as revealed by two-dimensional electrophoresis coupled with mass spectrometry in mouse cortex. Protein functional analysis revealed that these differentially expressed proteins mainly included apoptosis-associated proteins, axon guidance-associated proteins, axonogenesis-associated proteins and mitochondrial respiratory chain complex. Among these differentially expressed mitochondrial proteins, GRP75 (75 kDa glucose-regulated protein) and GRP78 (78 kDa glucose-regulated protein) were found to be significantly down-regulated as confirmed by Western-blot analysis. The down-regulation of GRP75 was shown to promote apoptosis. The down-regulation of GRP78/BiP could up-regulate endoplasmic reticulum (ER) stress mediators and thus cause apoptosis. Our study suggested that these differentially expressed mitochondrial proteins such as GRP75 and GRP78 could be involved in neurotoxicity caused by long-term low-dose copper exposure and serve as potential molecular targets for the treatment of copper neurotoxicity.

• 出版日期2016-11-30
• 单位暨南大学; 深圳市疾病预防控制中心; 上海交通大学