Natural product clitorin reduces myocardial damage following acute myocardial infarction by mediating NOX4/Nrf2 redox balance.

PURPOSE: Acute myocardial infarction (AMI) is a severe cardiovascular disease to which excessive oxidative stress is a pivotal contributor. Clitorin (CL), a natural flavonoid from plants and fruits, has demonstrated antioxidant potential; however, its role and mechanism in AMI remain unclear. This study aimed to elucidate the protective effects and mechanisms of CL in AMI.

METHODS

Forty-five male C57BL/6J mice were used to establish an AMI model by left anterior descending coronary artery ligation, followed by injection of 0.625, 1.25, or 2.5 mg/kg of CL. In vitro, oxygen-glucose deprivation (OGD) was induced in neonatal mouse cardiomyocytes (NMCMs), followed by administration of 10, 20, or 40 μM of CL. The therapeutic effects were assessed using triphenyltetrazolium chloride (TTC) staining, TUNEL staining, reactive oxygen species (ROS) staining, and flow cytometry. RNA sequencing, network pharmacology, SPR, CETSA, molecular docking, and Western blot were used for mechanistic studies.

RESULTS

In vivo, CL exerted cardioprotective effects by reducing myocardial infarct size, decreasing apoptosis, and improving cardiac function. In vitro, CL mitigated OGD-induced ROS production in NMCMs, reduced apoptosis, and protected mitochondrial function. Mechanistically, CL protected against AMI by directly binding to NOX4 and regulating the NOX4/Nrf2 axis. By inhibiting NOX4, promoting Nrf2 upregulation and nuclear translocation, and alleviating mitochondrial damage and ferroptosis, CL exerted antioxidant effects and improved AMI-induced myocardial injury.

CONCLUSION

This study is the first to elucidate the cardioprotective role of CL in AMI by regulation of the NOX4/Nrf2 pathway. These findings deepen our understanding of CL in AMI.