Micro(nano)plastics (MNPs) are emerging pollutants that
can adsorb
pollutants in the environment and biological molecules and ultimately
affect human health. However, the aspects of adsorption of intracellular
proteins onto MNPs and its biological effects in cells have not been
investigated to date. The present study revealed that 100 nm polystyrene
nanoplastics (NPs) could be internalized by THP-1 cells and specifically
adsorbed intracellular proteins. In total, 773 proteins adsorbed onto
NPs with high reliability were identified using the proteomics approach
and analyzed via bioinformatics to predict the route and distribution
of NPs following cellular internalization. The representative proteins
identified via the Kyoto Encyclopedia of Genes and Genomes pathway
analysis were further investigated to characterize protein adsorption
onto NPs and its biological effects. The analysis revealed that NPs
affect glycolysis through pyruvate kinase M (PKM) adsorption, trigger
the unfolded protein response through the adsorption of ribophorin
1 (RPN1) and heat shock 70 protein 8 (HSPA8), and are chiefly internalized
into cells through clathrin-mediated endocytosis with concomitant
clathrin heavy chain (CLTC) adsorption. Therefore, this work provides
new insights and research strategies for the study of the biological
effects caused by NPs.