Sulforaphane prevents diabetes-induced liver ferroptosis through activation of Nrf2 signaling axis

Abstract

Recently, we characterized the ferroptotic phenotype of the liver of diabetic mice and revealed the inactivation of Nrf2 as an integral part of diabetes-induced liver ferroptosis. We aim here to examine does sulforaphane, an Nrf2 activator and antioxidant, prevent diabetes-induced liver ferroptosis and the mechanisms involved. For that purpose, male C57BL/6 mice were divided into three groups: control, diabetic (streptozotocin-treated, 40 mg/kg/5 consecutive days), diabetic+sulforaphane treated (2.5 mg/kg, from day 1-42). Results showed that diabetes-induced inactivation of Nrf2 and decreased expression of its downstream antiferroptotic parameters crucial for antioxidative defense (HO-1, catalase, SOD), iron metabolism (ferroportin, ferritin), glutathione synthesis (xCT, GCLC, CTH, CBS) and recycling (GR) were reversed/increased by sulforaphane treatment. Antiferroptotic effect of sulforaphane in the diabetic liver was further evidenced through the increased level of glutathione, decreased accumulation of liable iron and lipid peroxides (4-HNE) and decreased tissue damage (fibrosis and infiltration). Finally, diabetes-induced increase in serum glucose, ALT, AST and triglyceride level was significantly reduced by sulforaphane. These findings revealed for the first time that sulforaphane prevents in vivo diabetes-induced liver ferroptosis through activation of Nrf2 signaling axis. This suggests sulforaphane as a promising therapeutic tool for preventing ferroptosis at least in diabetes and diabetes-related pathologies.