EFFECT OF A LONG-TERM TREATMENT WITH LOVASTATIN OR FENOFIBRATE ON HEPATIC AND CARDIAC UBIQUINONE LEVELS IN CARDIOMYOPATHIC HAMSTER

This study was undertaken to determine if long-term oral administratio n of lovastatin (50 mg/kg per day) or fenofibrate (200 mg/kg per day) was affecting ubiquinone levels in the heart and the liver of cardiomy opathic hamsters. After 23 weeks of treatment, ubiquinone concentratio ns (CoQ9 + CoQ10) and ubiquinone ratio (CoQ10/CoQ9) were determined in the heart and in the liver. Our results indicate that lovastatin sign ificantly decreased ubiquinone concentrations in the heart (-33%, P < 0.01) but not in the liver (-23%, NS) when compared to controls, where as fenofibrate did not alter these parameters. Ubiquinone homologues w ere not equally decreased during lovastatin treatment: the ratio betwe en CoQ10 and CoQ9 was significantly lowered in the heart (-33%, P < 0. 001) and in the liver (-75%, P < 0.001) of lovastatin-treated animals. These results suggest that 3-hydroxymethylglutaryl-coenzyme A reducta se inhibition (HMG-CoARI) associated with lovastatin treatment in card iomyopathic hamsters is more marked in the liver than in the heart, wh ile ubiquinone concentrations are more decreased in cardiac than in he patic tissues. Our data also showed that fenofibrate had no effect on ubiquinone levels.