Chronic Polystyrene Nanoplastics Exposure Reprograms Gene Expression, Alternative Splicing, and Disrupts Host Microbiome Metabolic Networks to Promote Atherosclerosis in LDLr- Knockout Mice
Although micro- and nanoplastics have been detected in human atherosclerotic plaques, their mechanistic contribution to disease pathogenesis remains poorly defined. Most experimental studies have used microplastics (particles > 1 m) in non-atherosclerotic animal models or the ApoE-/- mouse, relying on short-term exposure or single-pathway analyses, whereas the chronic cardiovascular effects of nanoplastics (< 100 nm) remain exceedingly scarce--despite their higher biological reactivity and greater tissue penetrance. To address this gap, this study employs a multi-omics approach to investigate the chronic (12-week) oral exposure to 80 nm polystyrene nanoplastics in LDLr-/- mice. We uniquely integrate aortic plaque quantification, hepatic transcriptomics with global alternative splicing profiling, gut microbiome 16S sequencing, and liver untargeted metabolomics to construct a unified host-microbiome-metabolite network. Nanoplastic exposure significantly exacerbates aortic lipid deposition, suppresses hepatic detoxification and anti-atherogenic lipid pathways primarily through transcriptional and post-transcriptional level changes driven by alternative splicing events (e.g., intron retention and isoform switching), and induces gut dysbiosis marked by a reduction in SCFA-producing commensals and enrichment of pro-atherogenic pathobionts--perturbations that correlate with specific hepatic functional modules. Metabolomic changes, including decreased levels of the glutathione precursor {gamma}-glutamylcysteine and the choline-derived metabolite neurine, implicate oxidative stress and TMAO-related pathways. Cross-species validation using human atherosclerotic transcriptomic and metagenomic datasets supports the clinical translatability. By integrating multi-level biological responses, this work establishes nanoplastics as an environmental cardiovascular risk factor and uncovers novel regulatory mechanisms involving splicing-associated transcriptional reprogramming and gut-liver crosstalk, offering potential early-warning biomarkers and therapeutic targets for nanoplastic-associated cardiovascular disease. HighlightsO_LIExposure to polystyrene nanoplastics (80 nm) increases aortic lipid burden in LDLr-/- mice. C_LIO_LIAlternative splicing and isoform switching were identified as novel hepatic responses. C_LIO_LISCFA-producing gut commensals are depleted, and pathobionts are enriched in response to nanoplastics. C_LIO_LIA gut-liver network links suppressed detoxification to gut microbial dysbiosis. C_LIO_LIMouse transcriptomics and metagenomics overlap with human atherosclerosis omics datasets. C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=142 SRC="FIGDIR/small/736446v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@196ad0eorg.highwire.dtl.DTLVardef@13b95d3org.highwire.dtl.DTLVardef@e963c4org.highwire.dtl.DTLVardef@94f60c_HPS_FORMAT_FIGEXP M_FIG Graphical Abstract C_FIG