Effects of atorvastatin therapy on protein oxidation and oxidative DNA damage in hypercholesterolemic rabbits

Our aim was to clarify the effects of hypercholesterolemic diet and administeration of atorvastatin on lipid peroxidation, protein oxidation and oxidative DNA damage in male New Zealand white rabbits.

We determined malondialdehyde (MDA), protein carbonyl (PCO) and total thiol (T-SH) levels in plasma and liver tissue, glutathione (GSH) levels in erythrocyte and liver tissue, and 8-hydroxy-2-deoxyguanosine (8-OHdG) levels in plasma. Twenty rabbits were randomly divided into two groups and fed with a high-cholesterol diet (fortified with 1% cholesterol) for 4 weeks. Such rabbits were subjected to either (Group 1) a high-cholesterol diet non-supplemented with atorvastatin (n=10) or (Group 2) a high-cholesterol diet supplemented with atorvastatin (0.3mg atorvastatin per day/kg body weight) for 4 weeks (n=10). A control group (n=5) (Group 3) was fed a cholesterol free diet for 4 weeks. Colorimetric methods were used to determine the level of the oxidative stress markers, except 8-OHdG, which was measured by ELISA.

Rabbits were fed with the high-cholesterol diet alone (Group 1) showed higher levels of lipid profile and oxidative protein and DNA damage than compared with dose of the control group (Group 3). Atorvastatin therapy has substantially beneficial effects on oxidative protein and DNA damage in hypercholesterolemic rabbits.

The current findings will, we hope, lead to a new insight into the pathogenesis of atherosclerosis. On the other hand inhibition of protein oxidation and DNA oxidation in the plasma by atorvastatin may be one of the pleiotropic effects of statins, and thus the underlying mechanism needs to be further clarifications.