Curcumin Loaded with Ferric Oxide Nanoparticles Reduces Hypoxic Injury in Myocardial Infarction by Regulating miR-208 and Activating SIRT1 Signaling Pathway

Background: Curcumin has antioxidant and anti-myocardial ischemic effects, but its low water solubility and bioavailability limit clinical application. Objectives: This study aims to explore whether curcumin-loaded ferric oxide nanoparticles alleviate hypoxic injury in myocardial infarction. Materials and Methods: Preparation of ferric oxide (Fe3O4) nanoparticle-loaded curcumin complex. A cardiomyocyte hypoxia model was established using ligation surgery. The complex, Fe3O4 nanoparticles, and curcumin were applied to the hypoxia model, respectively, and a blank control group was established. The expression of microRNA-208 (miR-208) in cells in each group was detected by fluorescence quantitative polymerase chain reaction. Western blot was used to detect the expression of sirtuin 1 (SIRT1), p53, and hypoxia-inducible factor 1-alpha proteins in cells in each group. The cell counting kit-8 was used to detect cell proliferation in each group. Results: The Fe3O4 nanoparticle-loaded curcumin complex was successfully prepared, and the myocardial infarction rat model was successfully constructed. In vivo experimental results show that Fe3O4 nanoparticles loaded with curcumin complex can significantly reduce the expression level of miR-208 and increase the activity of SIRT1. After hypoxic treatment of myocardial cells, adding composite nanoparticles can reduce cell damage, reduce the cell apoptosis rate, significantly reduce the size of myocardial infarction, and improve myocardial function, and the effect is stronger than curcumin alone. Conclusion: Fe3O4 nanoparticles loaded with curcumin activate the SIRT1 signaling pathway by downregulating miR-208, and inhibit the expression of p53 and HIF-1α, and ultimately reduce hypoxic injury in myocardial infarction. This provides new ideas and methods for the treatment of myocardial infarction.