Supporting information.

The oral administration of microplastics (MP) for 9 weeks induced disruption of hepatic lipid, glucose, and amino acid metabolism in C57BL/6-Lepem1hwl/Korl (Lep KO) mice with obesity. Therefore, we investigated whether MP-caused hepatic metabolism abnormalities can affect the structural variation of the fecal microbiota during obesity. The overall microbiota profile was analyzed in the feces of Lep KO mice treated with MP for 9 weeks. The lipid accumulation and steatosis area were significantly decreased in MP-treated Lep KO mice. Total microbiota with MP-caused difference identified from feces of Lep KO and wild type (WT) mice were classified into 10 phyla and 106 genera. Among them, two microbial phyla were significantly changed in Lep KO mice after treatment of MP, while significant alterations on 12 genera were detected in Lep KO mice treated with MP. Also, the Chao1 index for richness were remarkably decreased in both MP-treated Lep KO and WT mice, but Shannon index for evenness were increased in only MP-treated Lep KO mice. Therefore, the results of the present study suggest that MP-caused hepatic metabolism disruption may be closely linked to the dysbiosis of the fecal microbiota in Lep KO mice.