Low doses of ozone alleviate cardiomyocyte ferroptosis induced by hypoxia-reoxygenation injury via the AMPK-mTOR pathway

Background: Acute myocardial infarction (AMI), a sudden and dangerous form of cardiovascular diseases (CVDs), induces myocardial hypoxia-reoxygenation (H/R) injury, which exacerbates myocardial damage and potentially results in heart failure. In this study, we explored the effect of low-concentration ozone after hypoxia-reoxygenation injury.

Methods: CCK-8 assay and flow cytometry wisere performed to assess cell viability. To evaluate Ferroptosis, ferroptosis-related protein expression levels, intracellular Fe²⁺ levels, glutathione (GSH), and Reactive Oxygen Species (ROS) were assessed. We employed Erastin, a known Ferroptosis inducer to explore the relationship between Ferroptosis and ozone. Meanwhile, we employed the selective AMPK Inhibitor dorsomorphin to investigate how the ozone affects AMPK-mTOR pathway.

Results: The results discovered that an appropriate dose of ozone can effectively mitigate Ferroptosis in H9c2 cardiomyocytes induced by hypoxia-reoxygenation. Erastin successfully antagonized the effects of ozone, further confirming ozone's significant role in regulating Ferroptosis. Mechanistically, ozone effectively suppressed intracellular oxidative stress levels, thereby activating the AMPK-mTOR pathway. In addition, dorsomorphin successfully blocked the effects of ozone and exacerbated Ferroptosis following hypoxia-reoxygenation, suggesting the regulation of AMPK-mTOR pathway.

Conclusions: Low-concentration ozone treatment has shown promise in mitigating Ferroptosis by regulating the AMPK-mTOR pathway, highlighting its potential as a therapeutic agent for hypoxia-reoxygenation injury.

AMPK–mTOR pathway; Ferroptosis; Myocardial hypoxia–reoxygenation injury; Ozone.