Resveratrol-activated PI3K/AKT/mTOR signaling pathway attenuates ferroptosis by promoting NRF2/GPX4 metabolic pathway to mitigate IFN-gamma-mediated aplastic anemia

Abstract

Aplastic anemia (AA) is a severe hematological disorder caused by hyperactivated T cell-mediated hematopoietic failure. It is characterized by hematopoietic stem cell deficiency and hypocellular hematopoiesis in the bone marrow (BM). Ferroptosis, a specific type of programmed cell death, is defined by iron-dependent lipid peroxidation, which has garnered the attention of researchers due to its unique role and biological importance in various diseases. However, the correlation between immunological imbalance-induced ferroptosis and the mortality of hematopoietic stem cells within the BM microenvironment in AA is unclear. Resveratrol (RSV) is crucial in activating NRF2, hence influencing the onset and progression of diseases by regulating ferroptosis. This study aimed to investigate the roles and molecular mechanisms of RSV in the hematopoietic recovery of AA regarding ferroptosis. We measured some biomarkers in AA mice and IFN-gamma-treated 32D cells, representing AA syndromes and ferroptosis features. Furthermore, in RSV-treated 32D AA cells, cell activity, cell apoptosis, mitochondrial membrane potential, mitochondrial membrane permeability, and intracellular levels of MDA, ferrous iron, 4-HNE, GSH, ROS, and lipid peroxidation were assessed. Subsequently, additional in vitro and in vivo experiments were performed to investigate the mechanisms by which RSV effectively regulates NRF2 stability, further inhibiting ferroptosis in AA. We demonstrated that ferroptosis contributes to the occurrence and development of AA disease. RSV dose-dependently inhibits ferroptosis in 32D AA cells by targeting GPX4 expression, enhancing the cell activity of hematopoietic BM cells. Mechanically, RSV significantly increases NRF2 phosphorylation through the PI3K/AKT/mTOR signaling pathway, which maintains NRF2 stability to promote the GPX4 metabolic pathway in AA. Protein levels of p-AKT, p-mTOR, p-NRF2, and GPX4 were markedly increased in BM cells in RSV-treated AA mice, resulting in the suppression of AA development. Our data demonstrate that RSV effectively inhibits ferroptosis in AA or IFN-gamma-treated 32D cells by targeting the PI3K/AKT/mTOR signaling pathway, which enhances NRF2-mediated GPX4 transcription, thereby ameliorating AA symptoms in vitro and in vivo. This study concludes that RSV is a potential therapeutic drug for ferroptosis-related AA treatment.