[Effects of atorvastatin and CoQ(10) on myocardial energy metabolism in rabbits with hypercholesterolemia].

OBJECTIVE

To explore the interventional effects of atorvastatin and CoQ(10) on myocardial energy metabolism in rabbits with hypercholesterolemia.

METHODS

Forty male New Zealand white rabbits were randomly divided into 5 groups: i.e. normal control, high cholesterol, statin, coenzyme Q(10) 1 and coenzyme Q(10) 2. After feeding for 6 weeks, the fasting blood samples were collected through ear marginal vein and the serum level of total cholesterol was determined. Myocardium was sampled for ultrastructures by electron microscopy; high-performance liquid chromatography (HPLC) was used to measure myocardial mitochondria adenosine triphosphate (ATP) and coenzyme CoQ(10). Ultraviolet spectrophotometry was used to measure the activities of mitochondrial complexes II and IV.

RESULTS

In high cholesterol group, myocardial fibers were arrayed disorderly with partial rupture and dissolution. There was mitochondrial swelling with disorderly and fuzzy cristae. As compared with the controls, the activities of mitochondrial respiratory chain complexes II and IV declined (5.39 ± 0.53 vs 12.95 ± 0.99, 1.89 ± 0.26 vs 6.65 ± 0.95, P < 0.01), the contents of mitochondrial ATP and CoQ(10) decreased (0.17 ± 0.05 vs 0.44 ± 0.06, 0.09 ± 0.02 vs 0.25 ± 0.04, P < 0.01); for statin group versus high cholesterol group, the activities of mitochondrial respiratory chain complexes II and IV increased (9.12 ± 1.19 vs 5.39 ± 0.53, 4.61 ± 0.52 vs 1.89 ± 0.26, P < 0.01); the content differences of mitochondrial ATP and CoQ(10) were statistically insignificant. For CoQ(10) 1 group versus statin group, the differences of respiratory chain complexes II and IV were statistically insignificant; the contents of mitochondria ATP and CoQ(10) increased (0.35 ± 0.03 vs 0.16 ± 0.04, 0.17 ± 0.02 vs 0.07 ± 0.02, P < 0.01). For coenzyme Q(10) 2 group versus coenzyme Q(10) 1 group, none of the indices was statistically significant.

CONCLUSION

High cholesterol can cause myocardial ultrastructural changes and impaired mitochondrial energy metabolism. Atorvastatin reduces the myocardial structural damage and the combination of atorvastatin and CoQ(10) may further improve the myocardial mitochondrial energy metabolism.