title: Serum concentration and metabolism of cholesterol during rapeseed oil and squalene feeding.
abstract: The effect of rapeseed oil with and without added squalene was studied on serum lipids and cholesterol metabolism. Dietary rapeseed oil reduced LDL cholesterol by 10%, increased cholesterol precursors and plant sterols, and decreased cholestanol in serum during a 6-wk baseline period from initial values. Addition of 1 g squalene in rapeseed oil for 9 wk caused net increases in serum total, VLDL-, IDL-, and LDL-cholesterol concentrations by 12%, 34%, 28%, and 12%, respectively; squalene by five times; and cholesterol precursor sterols by up to 60%. Fecal squalene was 15% of the dietary intake, cholesterol absorption was unchanged, fecal neutral sterols were significantly increased, whereas, in contrast to the precursor sterols, the increase in cholesterol synthesis was insignificant. LDL apolipoprotein B was increased by 14% with unchanged removal but enhanced transport of LDL apolipoprotein B. A negative correlation between the changes in LDL apolipoprotein B removal and LDL cholesterol suggests that LDL receptor activity was down-regulated, allowing more of the LDL precursor lipoproteins to be converted to LDL. A subsequent 6-wk period on 0.5 g squalene/d normalized serum sterols.
authors.affiliation: Second Department of Medicine, University of Helsinki, Finland.
authors.forename: T A
authors.initials: TA
authors.lastname: Miettinen
authors.forename: H
authors.initials: H
authors.lastname: Vanhanen
mesh_terms: D001054:Apolipoproteins A / Q000032:analysis; D001055:Apolipoproteins B / Q000032:analysis; D001835:Body Weight; D001937:Brassica; D002784:Cholesterol / Q000097:blood* / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004336:Drug Antagonism; D005229:Fatty Acids, Monounsaturated; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000178:diet therapy*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010743:Phospholipids / Q000097:blood; D010938:Plant Oils / Q000008:administration & dosage / Q000494:pharmacology*; D000074262:Rapeseed Oil; D013185:Squalene / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D013261:Sterols / Q000097:blood; D014280:Triglycerides / Q000097:blood
chemical_list: D001054:Apolipoproteins A; D001055:Apolipoproteins B; D004041:Dietary Fats; D005229:Fatty Acids, Monounsaturated; D010743:Phospholipids; D010938:Plant Oils; D000074262:Rapeseed Oil; D013261:Sterols; D014280:Triglycerides; D013185:Squalene; D002784:Cholesterol