Long-Term Tetrabromobisphenol A Exposure Induces Gut Microbiota Imbalance and Metabolic Disorders via the Peroxisome Proliferator-Activated Receptor Signaling Pathway in the Regenerated Gut of Apostichopus japonicus

SIMPLE SUMMARY: Tetrabromobisphenol A, which has been found in water, sediment, soil, household dust, human tissues, and even human milk, possesses apparent negative impacts on development and growth, increases oxidative stress, and disrupts the endocrine system. In the present study, we found that TBBPA affected the gut microbiota and intestinal health in the regenerated intestine of Apostichopus japonicus. TBBPA exposure reduced the enzymatic activities of superoxide dismutase, malondialdehyde and the total of antioxidant capacity. The alpha diversity indices and the relative abundance of gut microbiota decreased after TBBPA exposure. We also found that TBBPA exposure affected lipid metabolism via the PPAR signaling pathway during the process of intestinal regeneration in A. japonicus via transcriptome sequencing, suggesting that TBBPA exposure can affect the composition and function of gut microbiota and intestinal health in the regenerated intestine of A. japonicus. ABSTRACT: Tetrabromobisphenol A (TBBPA), a commonly utilized brominated flame retardant, is found in many types of abiotic and biotic matrices. TBBPA can increase oxidative stress, disrupt the endocrine system, cause neurodevelopmental disorders and activate peroxisome proliferator-activated receptors to modulate lipid deposits in aquatic animals. However, the toxic mechanism of TBBPA on the gut microbiota and intestinal health remains unclear. Apostichopus japonicus is an ideal model for studying the relationship between environmental contaminants and intestinal health due to its unique capacity for evisceration and quickly regenerated intestine. In the present study, we investigated the toxic mechanism of TBBPA on the gut microbiota and intestinal health in the regenerated intestine of A. japonicus. The results show that TBBPA exposure decreased the health of the regenerated intestine and the enzymatic activities, alpha diversity indices, and the relative abundance of the gut microbiota. Transcriptome analysis shows that TBBPA exposure affected lipid metabolism via the PPAR signaling pathway during the process of intestinal regeneration in A. japonicus, suggesting that TBBPA exposure can affect the composition and function of the gut microbiota and intestinal health in the regenerated intestine of A. japonicus. These results provide a basis for further research on the potential toxicity of TBBPA to the intestinal health in animals.