A Fluorescent Probe for Imaging and Treating S-Nitrosation Stress in OGD/R Cells

Protein S-nitrosation, a redox post-translational modification elicited by nitric oxide (NO), is essential for modulating diverse protein functions and signaling pathways. Dysregulation of S-nitrosation is implicated in various pathological processes, including oxygen-glucose deprivation/reperfusion (OGD/R) injury, a widely used model for ischemia-reperfusion diseases. The dynamic changes in S-nitrosothiols (SNOs) during ischemia-reperfusion highlight the need for theranostic strategies to monitor and modulate SNO levels based on pathological progression. However, to date, no theranostic strategies have been reported for addressing dysregulated SNO in disease models, particularly in OGD/R conditions. Here, we report the development of a selective probe P-EHC, which could specifically react with SNOs to release EHC, not only exhibiting turn-on fluorescence with high quantum yield and good water solubility but also demonstrating macrophage migration inhibitory factor (MIF) inhibitory activity. In an OGD/R model of SH-SY5Y cells, we observed elevated SNO levels by using live-cell confocal imaging. Treatment of P-EHC significantly reduced intracellular reactive oxygen species (ROS), lowered total NO_x species, and improved cell viability in the OGD/R model. In summary, the simplicity and versatility of P-EHC suggest its broad applicability for monitoring SNO in various biological models and therapeutic contexts, particularly in ischemia-reperfusion diseases.