DBDPE (decabromodiphenyl ethane) induce oxidative stress and metabolic disorder in the intestine of silkworms (Bombyx mori L.)

Decabromodiphenyl ethane (DBDPE), is a widely used brominated flame retardant, could be enriched in the intestine of organisms. However, the potential impact of environmental related DBDPE concentrations in intestine is unknown. Here, by morphological observation, histopathology, high-throughput sequencing, and transcriptomics methods we evaluated the effects of different DBDPE concentrations on the intestine of silkworms. The morphological observation revealed DBDPE treatment significantly affects the development of silkworms. After exposure to DBDPE, the intestinal structure of silkworm were significantly damaged. Furthermore, the composition of the intestine microbiota was significantly affected by DBDPE exposure, and functional predictions revealed significant induction of immune pathway and protein export pathway, and significant disruption of some metabolic pathways. RNA-seq analysis revealed that DBDPE exposure significantly changed the transcription profiles, mainly manifested as induced oxidative stress and protein export process, downregulated transmenbrance transport processes, and a series of metabolic disorders, demonstrating that exposure to DBDPE affects the metabolism and immune function of silkworms. Finally, the significant correlation between intestine microbiota abundance and immune/metabolic/protein export related genes emphasizes the role of gut microbiota in the metabolic/immune/protein export dysregulation processes. To our knowledge, this study is the first to evaluate the toxic effects of environment related DBDPE concentrations in intestine and provide basic data for further DBDPE toxicity investigations and comprehensive ecological risk assessments.