K Ueno, Joscha Mulorz, Kenshi Yoshimura, Taisuke Harada, Renpei Nagashima, Masaki Takahashi, Kazuki Mori, Takayuki Kawashima, Haruto Nishida, Akihiro Higuchi, Osamu Tokumaru, Shinji Miyamoto
BACKGROUND: Ischemic heart disease remains the leading cause of death worldwide, and although early coronary revascularization is essential, it can paradoxically induce additional myocardial damage known as ischemia-reperfusion (I/R) injury, driven in part by excessive generation of reactive oxygen species (ROS). This study evaluated the cardioprotective potential of resorcimoline (RML), a newly developed free radical scavenger, in mitigating ROS-mediated myocardial injury in a preclinical setting. METHODS AND RESULTS: ROS production was induced in primary cardiomyocytes through hypoxia, angiotensin II, or hydrogen peroxide treatment. The antioxidant effects of RML were assessed by cytosolic and mitochondrial ROS assays. Cell viability and cytotoxicity were evaluated by metabolic activity and lactate dehydrogenase release assays. In vivo, myocardial I/R injury was induced in rats by transient coronary artery ligation followed by reperfusion. RML significantly reduced intracellular and mitochondrial ROS levels and improved cardiomyocyte viability in vitro. Consistently, in vivo DHE staining demonstrated that RML suppressed myocardial ROS accumulation, decreased infarct size, lowered serum troponin I, reduced apoptosis, and preserved left ventricular function, whereas these protective effects were not observed without reperfusion. CONCLUSIONS: RML exerts cardioprotective effects by scavenging ROS and mitigating downstream oxidative damage in both in vitro and in vivo models of myocardial I/R injury, suggesting promise as a therapeutic agent against reperfusion-induced myocardial injury.