Hypoxia, ROS, and HIF Signaling in I/R Injury: Implications and Future Prospects.

Ischemic heart disease (IHD) remains a leading cause of morbidity and mortality worldwide. Myocardial ischemia-reperfusion injury (MIRI) is a significant contributor to cardiac tissue damage, resulting from an abrupt reduction in blood flow that leads to a reduction in the supply of oxygen and nutrients. The resulting hypoxia triggers severe cellular injury and impairs organ function. Hypoxia-inducible factors (HIFs) play a central role in maintaining oxygen homeostasis in mammalian tissues. As primary oxygen sensors, HIFs trigger the transcriptional activation of a wide range of genes that facilitate cellular adaptation to reduced oxygen availability and assist in minimizing ischemic damage. Mitochondria are particularly vulnerable to hypoxic stress and are a major source of reactive oxygen species (ROS) during I/R injury. Stabilization of HIFs has been shown to reduce loss of cardiomyocytes under these conditions, highlighting the importance of HIF-dependent pathways in preserving mitochondrial integrity and promoting cell survival. Collectively, these observations suggest that hypoxia, HIF signaling, and mitochondrial dysfunction are tightly interconnected processes in the pathogenesis of IHD. This review, therefore, focuses on the interaction between hypoxia-driven HIF responses and mitochondrial regulation, emphasizing their implications for therapeutic strategies in managing IHD.