Lipid Nanoparticle-Mediated Oip5-as1 Delivery Preserves Mitochondrial Function in Myocardial Ischemia/Reperfusion Injury by Inhibiting the p53 Pathway.

Myocardial ischemia/reperfusion (MI/R) injury, a major contributor to poor prognosis in patients with acute myocardial infarction, currently lacks effective therapeutic strategies in clinical practice. The long noncoding RNA (lncRNA) Oip5-as1 can regulate various cellular processes, such as cell proliferation, differentiation, and survival. Oip5-as1 may have potential as a therapeutic target for MI/R injury as its upregulated expression has been associated with reduced infarct size and improved cardiac function in animal models, although how to effectively and safely overexpress Oip5-as1 remains unclear. Lipid nanoparticles (LNPs) are a versatile technology for targeted drug delivery in numerous therapeutic applications. Herein, we aimed to assess the therapeutic efficacy and safety of LNPs coloaded with Oip5-as1 and a cardiomyocyte-specific binding peptide (LNP@Oip5-as1@CMP) in a murine model of MI/R injury. To achieve this, LNP@Oip5-as1@CMP was synthesized via ethanol injection method. The structural components of LNP@Oip5-as1@CMP were physicochemically analyzed. A hypoxia/reoxygenation (H/R) model in HL-1 cells and coronary artery ligation in mice were used to simulate MI/R injury. Our results demonstrated that LNPs designed for cardiomyocyte targeting and efficient Oip5-as1 delivery were successfully synthesized. In HL-1 cells, LNP@Oip5-as1@CMP treatment significantly reduced mitochondrial apoptosis caused by H/R injury. In the murine MI/R model, the intravenous administration of LNP@Oip5-as1@CMP significantly decreased myocardial infarct size and improved cardiac function. Mechanistic investigations revealed that Oip5-as1 delivery inhibited the p53 signaling pathway. However, the cardioprotective effects of Oip5-as1 were abrogated by administrating Nutlin-3a, a p53 activator. Furthermore, no signs of major organ damage were detected after LNP@Oip5-as1@CMP injection. Our study reveals the therapeutic potential of LNPs for targeted Oip5-as1 delivery in mitigating MI/R injury. These findings pave the way for advanced targeted treatments in cardiovascular diseases, emphasizing the promise of lncRNA-based therapies.