Aging-associated GSK3β overexpression exacerbates hepatic ischemia-reperfusion injury through Nrf2 deficiency-induced...

Aging can exacerbate hepatic ischemia-reperfusion injury (HIRI), but the underlying mechanisms remain uncertain. In this study, the mechanisms through which age-related dysregulation of the GSK3β-Nrf2 axis promotes hepatocyte ferroptosis and exacerbates HIRI were investigated.

We used a comparative approach to analyze the following: 1) human liver specimens from young (25-35 years) and elderly (65-75 years) donors; 2) young and aged C57BL/6 mice and Nrf2-knockout (Nrf2-KO) mouse models subjected to HIRI; and 3) radiation-induced senescent L02 hepatocytes. Key interventions included the administration of the ferroptosis inhibitor ferrostatin-1 (Fer-1) and the GSK3β inhibitor lithium (LiCl).

Our study revealed that aging leads to significant downregulation of Nrf2 in human livers, aged mice, and senescent hepatocytes. This suppression of age-related Nrf2 exacerbates HIRI, as reflected by impaired antioxidant defenses and increased ferroptosis (elevated lipid peroxidation, iron overload, malondialdehyde (MDA) accumulation, glutathione (GSH) depletion and TFR upregulation). Genetic Nrf2 deficiency exacerbates these pathological changes in both cellular and animal models. Notably, treatment with Fer-1 effectively reduced liver damage biomarkers (ALT/AST) and ferroptotic responses in Nrf2-knockout systems. Mechanistically, aging-induced GSK3β overexpression drives Nrf2 dysfunction, establishing a GSK3β-Nrf2-ferroptosis axis involved in IRI progression. Notably, therapeutic targeting of GSK3β by microdose lithium or ferroptosis inhibition by Fer-1 alleviated HIRI in aged mice.

Our study revealed a novel aging-related pathogenesis axis in which GSK3β upregulation drives Nrf2 deficiency-mediated ferroptosis in hepatocytes, thereby exacerbating HIRI. Pharmacological targeting of this pathway may be a promising therapeutic strategy for elderly patients undergoing liver surgery.