Lipopolysaccharides (LPS) from Porphyromonas gingivalis (P.g.), which cause periodontal disease, contribute to the development of non-alcoholic steatohepatitis (NASH). After administering a high-fat diet for 18 weeks and intraperitoneal injections of P.g.-derived LPS for 6 weeks, it was suggested that Nrf2 in macrophages might play a crucial role in suppressing hepatic inflammation caused by P.g.