The effects of short-term dietary exposure to SiO2 nanoparticle on the domesticated lepidopteran insect model silkworm (Bombyx mori): Evidence from the perspective of multi-omics

Abstract

Silicon dioxide nanoparticles (nSiO2) are one of the widely utilized nanoparticle (NPSs) materials, and exposure to nSiO2 is ubiquitous. With the increasing commercialization of nSiO2, the potential risk of nSiO2 release to the health and the ecological environment have been attracted more attention. In this study, the domesticated lepidopteran insect model silkworm (Bombyx mori) was utilized to evaluate the biological effects of dietary exposure to nSiO2. Histological investigations showed that nSiO2 exposure resulted in midgut tissue injury in a dose-dependent manner. Larval body mass and cocoon production were reduced by nSiO2 exposure. ROS burst was not triggered, and the activities of antioxidant enzymes were induced in the midgut of silkworm exposure to nSiO2. RNA-sequencing revealed that the differentially expressed genes induced by nSiO2 exposure were predominantly enriched into xenobiotics biodegradation and metabolism, lipid, and amino acid metabolism pathways. 16 S rDNA sequencing revealed that nSiO2 exposure altered the microbial diversity in the gut of the silkworm. Metabolomics analysis showed that the combined uni- and multivariate analysis identified 28 significant differential metabolites from the OPLS-DA model. These significant differential metabolites were predominantly enriched into the metabolic pathways, including purine metabolism and tyrosine metabolism and so. Spearman correlation analysis and the Sankey diagram established the relationship between microbe and metabolites, and some genera may play crucial and pleiotropic functions in the interaction between microbiome and host. These findings indicated that nSiO2 exposure could impact the dysregulation of genes related to xenobiotics metabolism, gut dysbiosis, and metabolic pathways and provided a valuable reference for assessing nSiO2 toxicity from a multi-dimensional perspective.