Ischemic Rescue Potential of Conditioned Medium Derived from Skeletal Muscle Cells-Seeded Electrospun Fiber-Coated...

Revascularization procedures such as percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) are crucial to restore blood flow to the heart and are used in the treatment of myocardial infarction (MI). However, these techniques are known to cause myocardial reperfusion injury in the ischemic heart. The present study aims to mimic ischemia-reperfusion injury in vitro on primary human cardiomyocytes (HCMs) and use the established injury model to study the rescue mechanism of skeletal muscle cell (SkM)-seeded electrospun fiber-coated human amniotic membrane scaffold (EF-HAM) on injured cardiomyocytes through paracrine secretion. An in vitro ischemia-reperfusion injury model was established by exposing the HCM to 5 h of hypoxia, followed by a 6 h reoxygenation period. Six different conditioned media (CM) including three derived from SkM-seeded EF-HAMs were introduced to the injured cells to investigate the cardioprotective effect of the CM. Cell survival analysis, caspase-3 and XIAP expression profiling, mitochondrial membrane potential analysis, and measurement of reactive oxygen species (ROS) were conducted to evaluate the outcomes of the study. The results revealed a significant increase in the viability of HCM exposed to H/R injury by 77.2% (p < 0.01), 111.8% (p < 0.001), 68.7% (p < 0.05), and 69.5% (p < 0.05) when supplemented with HAM CM, EF-HAM 3 min CM, EF-HAM 5 min CM, and EF-HAM 7 min CM, respectively. Furthermore, CM derived from SkM-seeded EF-HAM scaffolds positively impacted hypoxia-/reoxygenation-induced changes in caspase-3 expression, mitochondrial membrane potential, and reactive oxygen species generation, but not in XIAP expression. These findings suggest that EF-HAM composite scaffolds can exert antiapoptotic and cardioregenerative effects on primary human cardiomyocytes through the paracrine mechanism.