Hypocholesterolemic Effect of Flaxseed and Its Oil in the Ovariectomized Golden Syrian Hamsters

Abstract

The health benefits of functional foods, such as flaxseed in lowering cholesterol and lowering the risks of atherosclerosis have already been discovered. Our earlier findings indicate that flaxseed reduced plasma cholesterol induced by ovarian hormone deficiency in Golden Syrian hamsters. This study was designed to investigate whether flaxseed oil (FO) exerts the same hypocholesterolemic effect as whole flaxseed (WF) and to gain insights into the hypocholesterolemic mechanism of action. Forty eight, 6-month-old female, Golden Syrian hamsters were either sham-operated (sham) or ovariectomized (OVX) and randomly assigned to four groups: sham, ovx, ovx plus either WF [15% diet] or FO [equivalent oil content to that of WF diet] and fed for 90 days. OVX elevated plasma total cholesterol concentrations in Golden Syrian Hamsters and WF was more effective than FO in reducing the increase in circulating cholesterol. To elucidate the hypocholesterolemic action, we quantified some key regulators of cholesterol metabolism in the liver microsomes using western blot analysis. Results indicate that flaxseed and its oil upregulated 7-? hydroxylase, an enzyme involved in bile acid synthesis, leading to cholesterol lowering effect.