Dimethyl Fumarate Attenuates Methotrexate Hepatotoxicity in Mice Via the Nrf2/HO-1/Anti-Apoptotic Signaling Pathway

Background: Methotrexate (MTX), a folate antagonist used to treat cancer and inflammatory diseases, is known to generate reactive oxygen species. Objectives: The research investigates the impact of dimethyl fumarate (DMF), a nuclear factor erythroid 2-related factor 2 (Nrf2) activator, on an MTX-induced mouse hepatotoxicity model. Methods: Forty-two mice were divided into 6 groups: control, MTX, DMF 120, and 3 groups of MTX co-treated with DMF 30, 60, and 120 mg/kg. Dimethyl fumarate was gavaged once daily for 10 days. On the fifth day, the animals received MTX 20 mg/kg intraperitoneally. On the eleventh day, the animals were sacrificed, and serum and liver samples were collected to assess the level of oxidative/anti-oxidative and apoptotic/anti-apoptotic markers. Results: Dimethyl fumarate prevented the increase of liver function enzymes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) induced by MTX (P < 0.001). It prevented the increase in AST and ALT levels, indicating liver recovery (P < 0.001). Furthermore, DMF restored antioxidant markers superoxide dismutase, catalase, glutathione peroxidase, and total thiol while reducing the level of thiobarbituric acid reactive substances (P < 0.001). Dimethyl fumarate also downregulated hepatic mRNA expression of caspase 3 and upregulated Bcl-2, heme oxygenase 1, and Nrf2 genes in MTX co-treated DMF groups. Conclusions: Dimethyl fumarate alleviates oxidative stress and apoptosis, which may be achieved by the Nrf2/HO-1 pathway. Therefore, DMF may be clinically effective in preventing or treating MTX-induced hepatotoxicity.