Aflatoxin B 1 Induces Inflammatory Liver Injury via Gut Microbiota in Mice.

Aflatoxin B 1 (AFB 1 ), a potent food-borne hepatocarcinogen, is the most toxic aflatoxin that induces liver injury in humans and animals. Species-specific sensitivities of aflatoxins cannot be fully explained by differences in the metabolism of AFB 1 between animal species. The gut microbiota are critical in inflammatory liver injury, but it remains to reveal the role of gut microbiota in AFB 1 -induced liver injury. Here, mice were gavaged with AFB 1 for 28 days. Then, the modulation of gut microbiota, colonic barrier, and liver pyroptosis and inflammation were analyzed. To further verify the direct role of gut microbiota in AFB 1 -induced liver injury, mice were treated with antibiotic mixtures (ABXs) to deplete the microbiota, and fecal microbiota transplantation (FMT) was conducted. The treatment of AFB 1 in mice altered gut microbiota composition, such as increasing the relative abundance of Bacteroides , Parabacteroides , and Lactobacillus , inducing colonic barrier dysfunction and promoting liver pyroptosis. In ABX-treated mice, AFB 1 had little effect on the colonic barrier and liver pyroptosis. Notably, after FMT, in which the mice were colonized with gut microbiota from AFB 1 -treated mice, colonic barrier dysfunction, and liver pyroptosis and inflammation were obliviously identified. We proposed that the gut microbiota directly participated in AFB 1 -induced liver pyroptosis and inflammation. These results provide new insights into the mechanisms of AFB 1 hepatotoxicity and pave a window for new targeted interventions to prevent or reduce AFB 1 hepatotoxicity.