The Effectiveness of Coenzyme Q1 and Q10 in Mitigating Myocardial Reperfusion/Ischemia (MI/R) Injury

We hypothesized that CoQ10 and CoQ1 would improve postreperfused cardiac contractile function and reduce infarct size when compared to I/R control with/without drug solvent. Our results indicate that CoQ1 was more effective than CoQ10 in restoring post-reperfused cardiac contractile function, but not infarct size during MI/R. These differences may be attributed to CoQ1’s stronger antioxidant effects. Results Isolated Rat Heart MI/R Experiments: Langendorff heart preparation was performed after anesthesia of male Sprague Dawley rats (275-325 g, Charles River, Springfield MA). Hearts were isolated and retrogradely perfused with Krebs’ buffer at a constant pressure of 80 mmHg with 37°C and pH of 7.35-7.45 by aerating with 95% O2/5% CO2 to get the baseline of cardiac parameters. After 15 min of baseline perfusion, the heart was put through global ischemia by stopping perfusion for 30 min, followed by reperfusion for 45 min. Krebs’ buffer alone, 0.2% DMSO alone (0.2% DMSO was used to solubilize CoQ1 and CoQ10), CoQ1 (20 μM), or CoQ10 (20 μM) was infused with 1 ml/min for the first 5 min of reperfusion. The pressure transducer (SPR-524, Millar Instruments, Inc., Houston, TX) was inserted into the left ventricle to record left ventricular end systolic pressure (LVESP), left ventricular end diastolic pressure (LVEDP), maximal rate of left ventricular systolic pressure over time (dP/dtmax), minimal rate of left ventricular diastolic pressure over time (dP/dtmin) and heart rate. Coronary flow was measured by a flow probe which was placed in line with perfusion line. Data was recorded using a Powerlab Station acquisition system (ADInstruments, Grand Junction, CO) every 5 min during the baseline and reperfusion. Determination of Infarct size: At the end of the experiments, the left ventricle of the hearts were sectioned into 2 mm thick slices that were subjected to 1% triphenyltetrazolium chloride (TTC) staining to detect infarcted (unstained) and viable (stained brick red) area. Infarct size was expressed as the percentage of infarcted tissue weight to the total tissue weight. Statistical Analysis: All data in the figures are presented as means ± S.E.M. The data was analyzed by analysis of variance using post hoc analysis with Fisher’s PLSD test. p<0.05 are considered to be statistically significant.