Probiotics ameliorate benzene-induced systemic inflammation and hematopoietic toxicity by inhibiting Bacteroidaceae-mediated ferroptosis

The intestinal microbiota is associated with the development of benzene-induced hematopoietic toxicity. Modulation of intestinal homeostasis by probiotic supplementation has been considered an effective strategy to prevent adverse health effects. However, the role and mechanism of probiotics in benzene-induced hematopoietic toxicity are unclear. After 45 days of exposure, benzene caused bone marrow hematopoietic toxicity in mice. Furthermore, we found that benzene altered the intestinal barrier in mice, leading to an increase in the abundance of Bacteroidaceae and the activation of systemic inflammation. Interestingly, Fe2+ accumulation, lipid peroxidation, and differential expression of ferroptosis proteins were observed in the intestinal tissues of benzene-exposed mice. After fecal microbiota transplantation, stool microbes from benzene-exposed mice led to the development of intestinal ferroptosis in recipient mice. In particular, oral probiotics significantly reversed elevated Bacteroidaceae and intestinal ferroptosis, ultimately improving benzene-induced hematopoietic damage. We further used the benzene metabolite 1,4-BQ to treat human normal colonic epithelial cells (NCM460) and intervened with the ferroptosis inhibitor liproxstatin-1 (Lip-1) to validate the relationship between intestinal ferroptosis and inflammation. The results showed that 1,4-BQ treatment resulted in increased intracellular ROS levels and abnormal expression of ferroptosis proteins and the inflammatory factors IL-5 and IL-13. However, the use of Lip-1 significantly inhibited oxidative stress, ferroptosis, and inflammation in NCM460 cells. This result suggested that ferroptosis might be involved in benzene-induced hematopoietic toxicity by mediating Th2-type systemic inflammation. Overall, these findings revealed a role for Bacteroidaceae-intestinal ferroptosis-inflammation in benzene-induced hematopoietic toxicity and highlighted that probiotics could be a promising strategy to prevent adverse hematologic outcomes.