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 Fe(2+) 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.