Proteomic profiling of RAW264.7 macrophage cells exposed to graphene oxide: insights into acute cellular responses

Abstract

Although the toxicity and molecular mechanisms of graphene oxide (GO) have been reported for several cell types, no proteomic study of GO has yet been conducted on macrophage cells. In this study, we used proteomics based on stable isotope labeling with amino acids in cell culture (SILAC) to quantify the proteomic changes in macrophage RAW 264.7 cells following GO treatment. We found 73 proteins that were significantly dysregulated after GO treatment. The down-regulated proteins included many ribosomal subunit proteins, indicating that GO affected cell growth. The most elevated proteins were lipoprotein lipase (LPL) and lysozyme 1 (LYZ1) which have not been reported before, and both can be used as candidate markers for GO exposure. Further enrichment analysis of the up-regulated proteins indicated these proteins are associated with the integrin complex and membrane rafts, as well as with two signal pathways: the phagosome and steroid biosynthesis pathways. We confirmed a GO concentration-dependent increase in membrane rafts and the production of phagosomes. GO exposure also induced necrotic cell death and an inflammation response in RAW 264.7 cells. We also observed an increase in the oxidative stress response (ROS) and autophagy, and the results suggest that ROS induced autophagy by the ROS-NRF2-P62 pathway.

Keywords:

• Nanotoxicology
• proteomics
• graphene oxide
• cellular response
• macrophages

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by Natural Science Foundation of Beijing Municipality (L172034), ‘Strategic Priority Research Program’ of Chinese Academy of Sciences (XDA09040300), the Key Research Program of the Chinese Academy of Sciences (KFZD-SW-210), and the National Natural Science Foundation of China (31700726 and 11601101).