Effects of two P/S ratios with same peroxidizability index value and antioxidants supplementation on serum lipid concentration and hepatic enzyme activities of rats.

BACKGROUND

High polyunsaturated/saturated fatty acid (P/S) ratio of diet decreases the risk of cardiovascular disease (CVD) with improvement of serum lipid profiles and inhibition of lipid peroxidation. This study was to investigate the effects of P/S ratio and antioxidants supplementation on lipid and peroxidation when dietary peroxidizability index (PI) value was the same.

METHODS

Female Sprague-Dawley rats weighing 100-120 g were fed four different experimental diets for 4 weeks. The P/S ratios were 0.38 (LP) and 4.81 (HP) when the PI value of diet was 81.22. These diets were supplemented with vitamin E 1000 mg/kg diet and selenium 2.5 mg/kg diet (LPS and HPS).

RESULTS

The total-cholesterol (T-C) and HDL-cholesterol concentrations of serum were higher in HP and HPS (p<0.001). The cardiac index and atherogenic index were lower in HP and HPS (p<0.001). Hepatic thiobarbituric acid reactive substance concentrations were higher in LP and LPS (p<0.001). However, P/S ratio and antioxidants had no effect on antioxidant enzyme activities in the liver.

CONCLUSION

A high P/S ratio diet has a beneficial effect on CVD risk even without antioxidant when the PI value is the same. We suggest that P/S ratio as well as PI value should be considered for reducing the risk of CVD.