Polystyrene Nanoplastics Disrupt the Intestinal Microenvironment by Altering Bacteria-Host Interactions through Extracellular Vesicle-Delivered microRNAs

Nanoplastics (NP) was used to treat intestinal bacteria, LS174T goblet-like cells, and differentiated Caco-2 enterocyte-like cells. The cross-treatments with bacterial extracellular vesicle (EV) or cells-derived EV were performed to assess whether the deterioration of intestinal environment caused by NP is achieved through indirect (microRNA) or direct (NP toxicity) effects. Our findings demonstrated that NP accumulation in the intestine of mice was observed, leading to notable alterations in intestinal miR-501-3p and miR-700-5p expression, which subsequently interfere with the expressions of tight junction (ZO-1) proteins and mucin (MUC)-13, and contribute to intestinal permeability. NP also increases the expression levels of miR-98-3p, miR-548z, miR-548h-3o, miR-548d-3p, miR-548az-5p, miR-12136, and miR-101-3p in LS174T goblet-like cells-derived EV, and these miRNA has potential for interferring ZO-1 expression. Evidence indicated that NP induced intestinal microbiota imbalance mediated by elevating Ruminococcaceae in vivo. These findings elucidate a novel pathway through which NP compromise intestinal integrity and indirectly alter intestinal microbiota composition (Ruminococcaceae), potentially leading to adverse health outcomes.