Heme drives cardiac endothelial senescence in sepsis via STING activation.

Summary

This study identifies heme as a novel ligand of STING that drives cardiac endothelial senescence and dysfunction in sepsis. Pharmacologic STING inhibition or enhancing heme clearance via hemopexin mitigated endothelial senescence and improved cardiac recovery in septic mice.

Key Findings

• Endothelial cells are the predominant senescent population in septic cardiac tissue.
• Heme acts as a novel ligand for STING, promoting its polymerization/activation and driving endothelial senescence.
• STING inhibition or increased heme clearance via hemopexin alleviates endothelial senescence and improves cardiac recovery in septic mice.
• Elevated heme correlates with increased endothelial senescence and impaired cardiac function in sepsis.

Clinical Implications

Suggests testing hemopexin supplementation and STING inhibitors to prevent or treat sepsis-induced cardiomyopathy; heme levels could serve as a risk biomarker for cardiac endothelial senescence.

Limitations

• Preclinical study without human validation; translational applicability needs confirmation.
• Potential off-target/systemic effects of modulating heme–STING pathways not fully characterized.

Future Directions

Evaluate hemopexin supplementation and STING inhibitors in large-animal models and early-phase clinical trials; develop biomarkers to monitor heme/STING activation in septic patients.