Sequential delivery of cardioactive drugs via microcapped microneedle patches for improved heart function in post myocardial infarction rats.

After myocardial infarction, the heart undergoes adverse remodeling characterized by a series of pathological changes, including inflammation, apoptosis, fibrosis, and hypertrophy. In addition to cardiac catheter-based re-establishment of blood flow, patients typically receive multiple medications that aim to address these different mechanisms underlying left ventricular remodeling. The current study aims to establish a versatile multi-drug delivery platform for the controlled and sequential delivery of multiple therapeutic agents in a single treatment. Toward this goal, we generated a microcapped microneedle patch carrying methylprednisolone, interleukin-10, and vascular endothelial growth factor. In vitro characterization demonstrated a time-sequenced release pattern of these drug: methylprednisolone for the first 3 days, interleukin-10 from day 1 to 15, and vascular endothelial growth factor from day 3 to 25. The therapeutic effects of the microneedle patch were evaluated in a rat model of acute myocardial infarction induced by permanent ligation of left anterior descending coronary artery. Heart function was measured using trans-thoracic echocardiography. Heart inflammation, apoptosis, hypertrophy and angiogenesis were evaluated using histology. Our data indicated that, at 28 days after patch transplantation, animals receiving the microneedle patch with sequential release of these three agents showed reduced inflammation, apoptosis and cardiac hypertrophy compared to the animals receiving control patch without sequential release of these agents, which is associated with the improved angiogenesis and heart function. In conclusion, the microneedle patch can be utilized to deliver multiple therapeutic agents in a controlled and sequential manner that aligns with the pathological phases following myocardial infarction. STATEMENT OF SIGNIFICANCE: The post-myocardial infarction heart remodeling is characterized by a series of pathological events including acute inflammation, apoptosis, fibrosis, cardiac hypertrophy, and depressed heart function. In current clinical practice, multiple procedures and drugs given at different time points are necessary to combat these series of pathological events. In this study, we developed a novel microcapped microneedle patch for the controlled sequential delivery of triple cardioprotective drugs aiming to combat acute inflammation and cardiac hypertrophy, and promote angiogenesis. This study presents a comprehensive therapeutic approach, with the microneedle patch addressing multifaceted pathological processes during post-myocardial infarction left ventricular remodeling. This cardiac drug delivery system has the potential to improve patient treatment by delivering drugs in alignment with the series of time-dependent pathological phases following myocardial infarction, ultimately improving clinical outcomes.