Abstract
Ferroptosis pitches in sepsis-caused pulmonary diseases. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) pitches in ferroptosis. This study explored the mechanism of adipose-derived MSC-EVs (ADMSC-EVs) protecting against ferroptosis in lung epithelial cells during sepsis. ADMSC-EVs were extracted using ultracentrifugation, followed by ADMSC and EV characterization. MLE-12 cells received 24-h lipopolysaccharide (LPS) treatment to mimic sepsis-induced ferroptosis, and treatment with EVs, a ferroptosis inhibitor (Fer-1), or the glutathione S-transferase zeta 1 overexpression plasmid. Cell viability, and levels of glutathione (GSH), malondialdehyde (MDA), Fe2+, reactive oxygen species (ROS), lipid peroxidation (LPO), ferroptosis-related proteins (glutathione peroxidase 4 [GPX4], solute carrier family 7 member 11 [SLC7A11]), miR-214-3p, and GSTZ1 were assessed. A mouse model of sepsis-induced acute lung injury was established by cecal ligation and puncture, and mice were intratracheally injected with EVs, followed by evaluation of resting ventilation per minute, inspiratory resistance, dynamic lung compliance, lung wet-to-dry weight ratio, and lung tissue cell morphology. The miR-214-3p-GSTZ1 targeted relationship was analyzed by Starbase database and dual-luciferase assay. LPS treatment reduced MLE12 cell viability, decreased GSH, GPX4 and SLC7A11 levels, and elevated Fe2+ and MDA contents and ROS and LPO levels, while ADMSC-EVs reversed these effects. miR-214-3p was down-regulated in the in vitro model. ADMSC-EVs carried miR-214-3p to target GSTZ1. GSTZ1 overexpression partly counteracted ADMSC-EV-inhibited lung epithelial cell ferroptosis during sepsis. In vivo, ADMSC-EVs inhibited ferroptosis through miR-214-3p/GSTZ1, thus improving sepsis-induced lung injury in mice. ADMSC-EVs carrying miR-214-3p attenuated ferroptosis in lung epithelial cells by targeting GSTZ1, thereby ameliorating sepsis-induced lung injury.