Single intravenous injection of CoQ10 reduces infarct size in a rat model of ischemia and reperfusion injury

Maintenance of mitochondrial activity and antioxidant features of coenzyme Q10 (CoQ10) could be an effective background for treatment of acute myocardial ischemia. Dietary uptake of CoQ10 is limited to only a few percent. In urgent cases, parenteral administration of CoQ10 could provide fast increase of its plasma and myocardial levels. The aim was to evaluate whether a single intravenous (i.v.) injection of solubilized CoQ10 before ischemia/reperfusion (IR) could lead to replenishment of its myocardial levels and limits subsequent myocardial IR injury. Methods: 30 min prior to coronary artery occlusion rats received i.v. solubilized CoQ10 (30 mg/kg) or saline (1 ml/kg). After 30 min of ischemia and 120 min of reperfusion, infarct zone of left ventricle (LV) and quantity of CoQ10 in LV were determined. Cardiac rhythm was monitored through the whole experiment. Results: At the beginning of reperfusion, arrhythmias were recorded in 8 (from 9) in saline and 2 (from 9) in CoQ10treated rats. Arrhythmias in CoQ10-treated rats arose later (40 ± 8 sec) and had less duration (26 ± 14 sec); 14 ± 13 sec and 52 ± 17 sec in saline treated rats respectively. At the end of reperfusion CoQ10 treated rats revealed: 2 fold higher CoQ10 content in LV (p < 0.01), limitation of infarct zone by 35% (p < 0.01). Higher levels of CoQ10 were accompanied by less infarct size (r = −0.77, p < 0.001). Conclusion: Single i.v. injection of CoQ10 effectively increased its myocardial levels and protected heart against IR injury by diminishing the size of the irreversibly damaged myocardium, decreasing frequency and duration of arrhythmias. The infarct zone inversely correlated with the quantity of CoQ10 in LV.