Abstract
Background: The present study was designed to investigate the influence of natural brown and black rice consumption on serum lipid parameters and hepatic enzyme activities in rats fed different combinations of grains. Methods: 50 male rats were divided into 4 groups and raised for 8 weeks on diets containing white rice (WH), white rice and brown rice (WHBR), white rice and black rice (WHBL), brown rice and black rice (BRBL). Blood samples were collected for lipid measurements, and the oxidant and antioxidant status of liver was evaluated. Results: Plasma triglyceride, total cholesterol and low-density lipoprotein cholesterol in rats fed the WH diet were higher than in other groups. High-density lipoprotein cholesterol was significantly higher in rats fed diets including black rice such as WHBL and BRBL compared with WH and WHBR. The level of thiobarbituric acid reactive substances in liver is shown to be higher in rats in the order of those fed WH, WHBR, WHBL and BRBL. While superoxide dismutase and chloramphenicol acetyltransferase did not differ among the 4 groups, glutathione and glutathione peroxidase in WH were significantly lower than in other groups. Conclusion: This study demonstrates that brown and black rice have cardioprotective effects.