Remimazolam attenuates myocardial ischemia/reperfusion injury by inhibiting ferroptosis involving the AKT/SLC7A11/GPX4 axis

Abstract

Remimazolam (RMZ) is an ultra-short-acting sedative anesthetic that provides protection against cerebral and hepatic ischemia/reperfusion injury. However, its potential cardioprotective effect in myocardial ischemia reperfusion injury (MIRI) remains to be fully elucidated. The present study investigated the hypothesis that RMZ can mitigate MIRI, clarifying its underlying mechanisms. Using a mouse MIRI model, the effects of RMZ on cardiac function, cell death, lipid peroxidation, Fe2+ accumulation and ferroptosis-related markers were assessed, together with transmission electron microscopy (TEM) imaging. Transcriptomic analysis identified ferroptosis signatures in cardiomyocytes (CMs). Ferrostatin-1 (Fer-1) served as a positive control to validate the anti-ferroptotic effects of RMZ. Additional mechanistic studies were conducted with H9C2 cells subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to evaluate cell death, lipid peroxidation, Fe2+ accumulation, TEM and the signaling pathways involved. In the MIRI model, mice treated with RMZ exhibited greater resistance to MIRI, as evidenced by improved cardiac function, reduced myocardial injury markers and decreased TUNEL-positive CMs. Transcriptomic analysis indicated the activation of ferroptosis following MIRI. Furthermore, RMZ and Fer-1 inhibited Fe2+ accumulation, restored glutathione (GSH) levels, enhanced glutathione peroxidase 4 (GPX4) expression and alleviated mitochondrial ferroptosis damage. In the OGD/R model using H9C2 cells, RMZ normalized Fe2+, GSH and GSH/oxidized GSH levels, decreased peroxidase activity and reduced OGD/R-induced ferroptosis, which was associated with the restoration of the protein kinase B (AKT)/solute carrier family 7 member 11 (SLC7A11)/glutathione peroxidase 4 (GPX4) axis. These findings demonstrated that RMZ protects against MIRI by inhibiting ferroptosis that involves the activation of the AKT/SLC7A11/GPX4 signaling cascade, highlighting its therapeutic potential for improving cardiac outcomes following reperfusion injury.