Impact of particulate microplastics generated from polyethylene terephthalate on gut pathology and immune microenvironments

Environmental microplastics have emerged as a critical issue in maintaining the planetary ecosystem. In this study, we generated particulate microplastics from polyethylene terephthalate (PM-PET) and investigated their impact in the gut by using mouse models and implementing histological examinations, as well as multi-omics analysis for colonic immune cells and microbiota. As a result, his-tological approaches showed that chronic and physiological low dose exposure of PM-PET did not affect intestinal pathology and mucin barriers, respectively. Moreover, immunohistochemical analysis demonstrated that the numbers of T cells, B cells, macrophages, and granulocytes were not affected by the expo-sure to PM-PET. However, RNA-seq analysis revealed that PM-PET had a sub-stantial impact on the transcriptome in gut immune cells and their metabolisms, while 16s rRNA metagenomic analysis showed that the composition of micro -biota was modestly affected. These results suggest an unexpected role played by the PM-PET in affecting gut immune homeostasis without detectable inflam-mation.

Automated summary

In this study, the researchers investigated the impact of particulate microplastics generated from polyethylene terephthalate (PM-PET) on the gut using mouse models and various analytical methods. The results showed that chronic and physiological low dose exposure to PM-PET did not affect intestinal pathology and mucin barriers, but had a substantial impact on the transcriptome and metabolisms of gut immune cells. The composition of the gut microbiota was also modestly affected by PM-PET exposure.