Integrating proteomics, metabolomics and typical analysis to investigate the uptake and oxidative stress of graphene oxide and polycyclic aromatic hydrocarbons†
Abstract
Graphene oxide (GO) is an emergent engineered nanomaterial that shows great potential for use in agricultural applications, such as promoting crop production and controlling insect pests. Polycyclic aromatic hydrocarbons (PAHs) are widely distributed and can enter crops via contaminated water, soil and air. Therefore, it is crucial to understand the potential risks of the co-exposure of crops, such as rice, to GO and PAHs. However, information regarding the effects of GO on PAH toxicity and the specific molecular responses to GO is lacking. The present work revealed that GO significantly enhanced the accumulation of PAHs by 26.4–92.5% in rice and that PAH accumulation was also influenced by temperature and glycerol. GO further promoted increased aryl hydrocarbon receptor (AhR) and cytochrome P450 levels, which are induced by PAHs. The altered proteins, including ascorbate peroxidase (APX), aquaporins and those involved in ATP synthesis, were mainly associated with oxidative stress and transmembrane transport. Amino acid metabolism was the primary metabolic pathway influenced by GO and PAHs. Arabinose and pentanoic acid were positively associated with the uptake of PAHs and oxidative stress, respectively, during co-exposure to GO. The abovementioned results highlight the potential risks and specific molecular mechanisms of emergent engineered nanomaterials during co-exposure with traditional organic pollutants.