Bile acid-binding activity of young persimmon (Diospyros kaki) fruit and its hypolipidemic effect in mice

Abstract

The hypolipidemic effects and bile acid-binding properties of young persimmon (Diospyros kaki) fruit were examined. In an animal experiment, male C57BL/6.Cr mice (n = 5) were fed an AIN-76-modified high fat diet supplemented with 2% or 5% (w/w) dried young persimmon fruit (YP) for 10 weeks. The intake of YP significantly enhanced fecal bile acid excretion and lowered the concentration of hepatic lipids and plasma cholesterol. Analysis of gene expression in liver tissue showed that 2% or 5% YP up-regulated the expression of the sterol regulatory element-binding protein-2 gene. In the 5% group, there were increased expressions of the genes for cholesterol 7alpha-hydroxylase and the low-density lipoprotein receptor. Next, the bile acid-binding ability of YP was analysed in vitro using cholic acid (CA). In 100-2000 microM CA solutions, 1% (w/v) YP adsorbed approximately 60% of CA, while dried mature persimmon fruit adsorbed approximately 20% of CA. The positive control, cholestyramine, adsorbed approximately 80% of CA in the 100-2000 microM CA solutions. A crude tannin extract from YP, which contained 54.7% condensed tannins, adsorbed approximately 78% of CA in the 2000 microM CA solutions. These results suggest that the ability of YP to bind bile acid contributes to its hypolipidemic effect in mice.