Ultrasound-Targeted β-Catenin Gene Therapy Improves the Cardiac Function in Mice After Myocardial Infarction.

Abstract

Gene therapy has received great attention as a therapeutic approach to improve cardiac function post-myocardial infarction (MI), but its limitation lies in the lack of targeting. This study explored the use of ultrasound-targeted microbubble destruction (UTMD) technique to deliver β-catenin gene to the myocardium, aiming to evaluate its efficacy in preventing cardiac dysfunction post-MI. A cationic microbubble solution containing β-catenin gene pcDNA3.1 plasmid was injected through the tail vein at a rate of 0.6 mL/h, and ultrasound beams were delivered to the heart using GE Vivid 7 Medical Ultrasound System M3s Transducer. Bioluminescence imaging was used to analyze the efficiency of UTMD gene transfection into the myocardium. β-catenin levels were detected by real-time polymerase chain reaction and western blot. Additionally, MI was induced in mice by surgical ligation of the left coronary artery, and cardiac function was evaluated using echocardiography at 14 and 28 days post-surgery. Masson's trichrome staining was employed to determine infarct size. Blood vessel density was also measured. TUNEL assay was used to measure cardiomyocyte apoptosis. Furthermore, mouse cardiac stem cells were isolated using flow cytometry, and Giemsa stain was applied to evaluate the colony adhesion. UTMD delivered the gene to the heart with high efficiency and specificity in vivo. The β-catenin expression was significantly increased in the myocardium (P < 0.01). After MI, the β-catenin group exhibited a notable improvement in the gene therapy-induced neovascularization in the border zone (P < 0.01) and the number and function of cardiac stem cells (P < 0.01), and a significant decrease in cardiomyocyte apoptosis in the heart tissue (P < 0.01). β-catenin gene pre-treated with UTMD can reduce the impact of myocardial injury and promote cardiac self-repair after MI.