There and back again: cellular uptake and bidirectional transport of nanoplastics.

Abstract

Nanoplastics (NPs) are an emerging class of environmental contaminants that are found in our food, water and air, and have been detected at the cellular and organ levels in humans and animals. Cell culture experiments suggest that nanoplastics enter cells primarily through endocytosis, and progress through the endo-lysosomal pathway to accumulate in lysosomes. This uptake is influenced by nanoplastic surface chemistry, size, shape and presence of a protein corona. Due to their resistance to enzymatic degradation, nanoplastics may either persist in lysosomes, potentially leading to lysosomal damage, or escape into the cytosol. Long-range intracellular transport is carried out by the motor proteins kinesin and dynein moving along microtubule tracks. In vitro and cellular studies have shown that both kinesin and dynein motors can bind and transport polystyrene nanoparticles, which raises the possibility that other nanoplastics could also hijack the intracellular transport system. This long-range transport is particularly important in the context of the brain where nanoplastics could move long distances along axons and dendrites and spread to distant regions of the nervous system. This review examines current research on nanoplastic uptake and transport in cells to synthesize our current understanding of the journey nanoplastics take through the endo-lysosomal pathway and along neuronal axons.

Abstract as supplied by the indexing source. © the authors / publisher.