Abstract:In this study, Balb/c mice were exposed to benzopyrene at different doses of 12.5, 62.5, 125, and 250 mg/kg bw to study its dose-response relationship in physiological damage and gut microbiota dysbiosis. The body weight, serum biochemical indicators and oxidative stress indicators of different organs were measured. The results showed that the body weight increased significantly at the dose of 62.5 mg/kg, while decreased sharply at dose of 250 mg/kg. In addition, AST and ALT levels increased gradually with a dose-dependent effect. HDL-C, LDL-C, TC, TG, ALP, and TP levels were significantly decreased only in the 250 mg/kg dose group. Moreover, a dramatic increase in SOD was found only in the livers of mice in the 250 mg/kg dose group, while there was no difference in MDA levels in liver, lung, and colon in all groups. Furthermore, the diversity and species composition of gut microbiota were analyzed in the control group and the 250 mg/kg benzopyrene dose group. The results showed that the abundance of S24-7, Clostridiales, Ruminococcus and Rikenellaceae were decreased strikingly, while the abundance of Enterobacteriaceae, Lactobacillus, Pseudomonas, and Allobaculum were elevated significantly after benzopyrene exposure at dose of 250 mg/kg. In conclusion, gut microbiota dysbiosis maybe one of the ways that benzopyrene causes physiological damage, which provides an important reference for studying the dose-response relationship of benzopyrene and its damage mechanisms.