Caffeic Acid Inhibits Oxidative Stress and Reduces Hypercholesterolemia Induced by Iron Overload in Rats

The effects of caffeic acid, a major phenolic compound of the diet, on oxidative stress and cholesterolemia are studied in rats submitted to oxidative stress by iron overload. Male Wistar rats were fed semi-synthetic diets containing regular (50 mg/kg diet) or high (2000 mg/kg) doses of iron with and without caffeic acid (6460 mg/kg) for 4 weeks. The high doses of iron induced an increase of lipid oxidation in the liver, as measured by thiobarbituric acid-reactive substances (TBARS), and an increase of cholesterolemia. Caffeic acid fully prevented the pro-oxidant effects of high iron doses (p < 0.001). It also reduced lipid peroxidation in rats fed the low iron dose (p < 0.05). Caffeic acid also increased vitamin E levels in plasma (2.74 mumol/L to 4.09 mumol/L for normal diet; p < 0.001; 2.78 mumol/L to 4.94 mumol/L for iron supplemented diet p < 0.001). Iron-induced hypercholesterolemia was inhibited by caffeic acid (1.07 g/L to 0.82 g/L; p < 0.001). These results demonstrate the antioxidative capacity of caffeic acid, a highly bioavailable polyphenol, in an in vivo model of oxidative stress.