Integrate Molecular Docking and Animal Model Validation into the Research of the Effect and Potential Mechanism of Eupatilin Against Myocardial Ischemia/Reperfusion Injury

Background Myocardial ischemia/reperfusion (I/R) injury refers to myocardial tissue damage caused by blood reperfusion after acute heart ischemia caused by coronary artery thrombosis and others. This process is closely related to inflammation and endoplasmic reticulum (ER) stress, and there is currently no ideal prevention means. In recent years, some traditional natural plant products with anti-inflammatory and anti-ER stress properties have been used to counteract myocardial I/R injury. Eupatilin (EPT), a pharmacologically active flavone derived from the Artemisia plant species, possesses significant anti-inflammatory and anti-ER stress activity. Still, its protective effect against myocardial I/R injury in vivo has not been revealed. Objectives This study aimed to evaluate EPT’s effect and potential mechanism against myocardial I/R injury. Materials and Methods The rat myocardial I/R injury model was prepared and treated with EPT. Then, the levels of myocardial injury markers and hematoxylin and eosin staining were used to evaluate the pathological damage of the myocardial tissue. Western blotting was used to detect the expression of key proteins in the potential signaling pathways. Results It was found that EPT could significantly reduce the levels of myocardial injury markers lactate dehydrogenase and creatine kinase, decrease the levels of inflammatory factors, and reduce apoptosis and pathological damage in myocardial tissue. In addition, the expression of key proteins in purinergic P2x7 receptor (P2X7R)/NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3), Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3)/suppressor of cytokine signaling 3 (SOCS3) pro-inflammatory pathways, and pancreatic endoplasmic reticulum eIF2alpha kinase (PERK/eIF2α)/activating transcription factor 4 (ATF4)/C/EBP homologous protein (CHOP) ER stress pathway was significantly downregulated in the EPT-treated group. Molecular docking simulations showed that this may be associated with the fact that EPT can bind to P2X7R, PERK, and other proteins in the aforementioned pathways. Conclusion This study demonstrated that EPT could attenuate myocardial I/R injury in rats, and the protective mechanism was related to the ability of EPT to bind to the initiating proteins of the P2X7R/NLRP3 pro-inflammatory pathway and the PERK/eIF2α/ATF4/CHOP ER stress pathway, which inhibited the inflammatory response and ER stress, thus reducing cardiomyocyte apoptosis. Our findings provide some valuable references for the future application of EPT in treating myocardial I/R injury.