Systematic toxicity evaluation of polystyrene nanoplastics on mice and molecular mechanism investigation about their internalization into Caco-2 cells

• Published in: Journal of hazardous materials Vol. 417; p. 126092
• Main Authors: Xu, Dihui, Ma, Yuhan, Han, Xiaodong, Chen, Yabing
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 05.09.2021
• Subjects: Internalization; Intestinal epithelial cells; Mice; Polystyrene nanoplastics; Toxicity evaluation; Toxicity evaluation; Mice; Polystyrene nanoplastics; Internalization; Intestinal epithelial cells
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.126092

There is a growing concern regarding the toxic effects of nanoplastics (NPs) on aquatic and marine organism, while relatively few studies about their toxicity evaluation on mammals are conducted. In the present study, we observed accumulation of polystyrene NPs (PS NPs) in mice spleen, lung, kidney, small intestine, large intestine, testis, and brain after oral exposure to PS NPs (~100 nm, 10 mg/mL, 100 μL) for 28 days, and NPs were identified to induce cell apoptosis, inflammation, and structure disorder in these tissues. We also found that PS NPs could bring about hematological system injury and lipid metabolism disorder. Further in vitro studies identified that PS NPs could be absorbed by the intestinal epithelial Caco-2 cells by macropinocytosis and clathrin-mediated endocytosis, and induced disruption of tight junction between Caco-2 cells. Moreover, we found that it was easier for PS-NH2 and PS-COOH to enter into Caco-2 cells, which may be associated with observed stronger toxicity of PS-NH2 and PS-COOH NPs. In summary, this study demonstrated that NPs exposure brings about toxic effects to mice. This study could provide new insights regarding the distribution of NPs in humans, and helps us to evaluate the potential physiological risks of NPs to human beings. [Display omitted] •We systematically examined the distribution pattern of polystyrene nanoplastics in mice.•We evaluated the physiologic effects of nanoplastics in mice.•We investigated the molecular mechanism underlying the internalization of nanoplastics into Caco-2 cells.•We compared toxic effects of nanoplastics with different surface modifications on mice and Caco-2 cells.