Daily consumption of black soybean (Glycine max L.) seed coat polyphenols attenuates dyslipidemia in apolipoprotein E-deficient mice

Abstract

Daily consumption of black soybean seed coat polyphenols attenuates dyslipidemia in apolipoprotein E-deficient mice. • Black soybean seed coat extract (BE) rich in polyphenols, such as cyanidin glucoside. • Apolipoprotein E-deficient (ApoE −/− ) mice spontaneously develop dyslipidemia. • BE lowered serum and hepatic total cholesterol and triglyceride levels in ApoE −/− mice. • These were characteristic in ApoE −/− mice, but not in their corresponding wild-type. Black soybean ( Glycine max L.) seed coat extract (BE) is rich in polyphenols, including epicatechin, procyanidin, and cyanidin-3-glucoside. We evaluated the effects of daily consumption of BE in apolipoprotein E-deficient (ApoE −/− ) mice. ApoE −/− and wild-type BALB/c mice were fed a 20% fat diet with or without 1% BE for 8 weeks. Bodyweight was unaffected by BE. BE supplementation significantly lowered serum and hepatic total cholesterol and hepatic triglyceride levels. Hepatic mRNA expression of cholesterol 7α-hydroxylase ( Cyp7a1 ) and peroxisome proliferator-activated receptor α ( Pparα ) were significantly stimulated in ApoE −/− mice consuming the BE diet. These effects were characteristic in ApoE −/− mice, but not in their corresponding wild type. In conclusion, it is clear that dietary consumption of BE affected blood and hepatic levels of cholesterol and triglyceride in ApoE −/− mice, and consequently exerted preventive effects for dyslipidemia. Putative mechanisms include the upregulation of hepatic Cyp7a1 and Pparα mRNA expression.