Rice protein regulates HDL metabolism-related gene expression and enzyme activity in adult rats

To elucidate whether rice protein possess a vital function in regulating high density lipoprotein (HDL) metabolism, the effects of rice protein (RP) on HDL metabolism-related gene expressions and enzyme activities were investigated in adult rats. Compared with casein, lipid contents in plasma and liver were effectively reduced by RP-feeding, accompanying significant increased ratio of HDL to cholesterol or triglyceride. RP increased mRNA levels of lecithin-cholesterol acyltransferase, adenosine triphosphate-binding cassette transporter A1, scavenger receptor class B type I and liver X receptor a, as compared to casein. Hepatic activities of lipoprotein lipase and hepatic lipase were significantly stimulated by RP, whereas no significant difference of plasma lecithin cholesterol acyltransferase activity was found in RP with respect to casein. Results demonstrated that rice protein could effectively regulate HDL metabolism through modifying the HDL metabolism-related gene expression levels and lipolytic enzyme activities, which involved with a hypocholesterolemic action during the adult period. (C) 2014 Elsevier Ltd. All rights reserved.