Plasma cholesterol-raising potency of dietary free cholesterol versus cholesteryl ester and effect of β-sitosterol

The present study (i) compared plasma cholesterol-raising activity of free cholesterol (FC) with that of cholesteryl palmitate (CP) and (ii) examined plasma cholesterol-reducing activity of β-sitosterol in FC-induced and CP-induced hypercholesterolemia. Male hamsters were divided into five groups and fed one of the five diets containing no cholesterol (NC), 2.6 mmol cholesterol (C), 2.6 mmol cholesterol plus 2.6 mmol β-sitosterol (C+S), 2.6 mmol cholesteryl palmitate (CP), and 2.6 mmol CP plus 2.6 mmol β-sitosterol (CP+S), respectively, for 8 weeks. Hamsters fed diet C had plasma TC of 317.5 mg/dl whereas hamsters fed diet CP has plasma TC of 281.3 mg/dl. β-Sitosterol reduced plasma TC by 17.4% and 11.6%, respectively, in FC-induced and CP-induced hypercholesterolemia (not significant). It was concluded that plasma cholesterol-raising activity of dietary cholesterol was a function of its chemical forms in diet, and β-sitosterol could similarly suppress the hypercholesterolemia induced by both dietary FC and CP.