title: Effect of dietary cholesterol and plant sterol consumption on plasma lipid responsiveness and cholesterol trafficking in healthy individuals.
abstract: Dietary cholesterol and plant sterols differentially modulate cholesterol kinetics and circulating cholesterol. Understanding how healthy individuals with their inherent variabilities in cholesterol trafficking respond to such dietary sterols will aid in improving strategies for effective cholesterol lowering and alleviation of CVD risk. The objectives of this study were to assess plasma lipid responsiveness to dietary cholesterol v. plant sterol consumption, and to determine the response in rates of cholesterol absorption and synthesis to each sterol using stable isotope approaches in healthy individuals. A randomised, double-blinded, crossover, placebo-controlled clinical trial (n 49) with three treatment phases of 4-week duration were conducted in a Manitoba Hutterite population. During each phase, participants consumed one of the three treatments as a milkshake containing 600 mg/d dietary cholesterol, 2 g/d plant sterols or a control after breakfast meal. Plasma lipid profile was determined and cholesterol absorption and synthesis were measured by oral administration of [3, 4-13C] cholesterol and 2H-labelled water, respectively. Dietary cholesterol consumption increased total (0·16 (sem 0·06) mmol/l, P=0·0179) and HDL-cholesterol (0·08 (sem 0·03) mmol/l, P=0·0216) concentrations with no changes in cholesterol absorption or synthesis. Plant sterol consumption failed to reduce LDL-cholesterol concentrations despite showing a reduction (6 %, P=0·0004) in cholesterol absorption. An over-compensatory reciprocal increase in cholesterol synthesis (36 %, P=0·0026) corresponding to a small reduction in absorption was observed with plant sterol consumption, possibly resulting in reduced LDL-cholesterol lowering efficacy of plant sterols. These data suggest that inter-individual variability in cholesterol trafficking mechanisms may profoundly impact plasma lipid responses to dietary sterols in healthy individuals.
authors.affiliation: 1Department of Human Nutritional Sciences,University of Manitoba,Winnipeg,MB R3T 2N2,Canada.
authors.forename: Peter A S
authors.initials: PA
authors.lastname: Alphonse
authors.affiliation: 1Department of Human Nutritional Sciences,University of Manitoba,Winnipeg,MB R3T 2N2,Canada.
authors.forename: Vanu
authors.initials: V
authors.lastname: Ramprasath
authors.affiliation: 1Department of Human Nutritional Sciences,University of Manitoba,Winnipeg,MB R3T 2N2,Canada.
authors.forename: Peter J H
authors.initials: PJ
authors.lastname: Jones
mesh_terms: D000293:Adolescent; D000328:Adult; D001692:Biological Transport; D002791:Cholesterol, Dietary / Q000008:administration & dosage / Q000494:pharmacology*; D018592:Cross-Over Studies; D004032:Diet; D004311:Double-Blind Method; D005504:Food Analysis; D006801:Humans; D050356:Lipid Metabolism / Q000187:drug effects*; D008055:Lipids / Q000097:blood*; D008875:Middle Aged; D010840:Phytosterols / Q000008:administration & dosage / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D002791:Cholesterol, Dietary; D008055:Lipids; D010840:Phytosterols
keywords:  FSR fractional synthetic rates;  TC total cholesterol; Cholesterol kinetics; Dietary cholesterol; Plant sterols; Plasma lipoproteins