The adverse effects of developmental exposure to polystyrene nanoparticles on cognitive function in weaning rats and the protective role of trihydroxy phenolacetone

Polystyrene nanoplastic(PS-NP) can originate from sources such as plastic waste and industrial wastewater and have been shown to have deleterious effects on abnormal neurobehaviors. However, evidence regarding the health impacts, biological mechanisms, and treatment strategies underlying developmental exposure to low dose PS-NP is still lacking. This study aimed to fill this knowledge gap by administering low doses of PS-NP(50 and 100 μg/L) to weaning rats for 4 consecutive weeks. Behavioral and morphological experiments were performed to evaluate hippocampal damage, and transcriptomics and Assay for Transposase Accessible Chromatin with hight-throughput sequencing(ATAC) analyses were conducted to identify potential key targets. Additionally, Connectivity Map(CMap) database, Limited proteolysis-mass spectrometry(LiP-SMap), and molecular-protein docking were used to examine potential phytochemicals with therapeutic effects on key targets. The results indicated that developmental exposure to PS-NP can induce hippocampal impairment and aberrant neurobehaviors in adulthood. Multi-omics analyses consistently showed that apoptosis-related signaling pathways were sensitive to PS-NP exposure, and mitogen-activated protein kinase 3(Mapk3) was identified as the core gene by the gene network, which was further validated in vitro experiments. The CMap database provided a series of phytochemicals that might regulate Mapk3 expression, and trihydroxy-phenolacetone(THP) was found to have directly binding sites with Mapk3 through LiP-SMap and molecular docking analysis. Furthermore, THP administration could significantly alleviate apoptosis induced by PS-NP exposure in primary hippocampal cells through down-regulation of Mapk3. These findings suggested that developmental exposure to PS-NP has adverse effects on cognitive function and that THP can alleviate these effects by directly binding to Mapk3.