Modification of triacylglycerides and apolipoprotein B in rats fed diets containing whole milk, skim milk and milk proteins.
The objective of this study was to determine the effects of diets containing milk and milk protein fractions on plasma and hepatic lipids, apolipoprotein B mRNA abundance, and plasma apolipoprotein concentrations and lipoprotein composition. Male rats were fed for 6 wk diets that contained (wt/wt) 76% whole milk (WM diet), 55% skim milk (SMFF diet), 22% casein (CAS diet), 22% whey protein isolate (WHY diet) or 55% skim milk-low fat (SMLF diet). The fat concentration in the SMLF diet was 7%. Butter oil (20%) and corn oil (2%) were added to the SMFF, CAS and WHY diets. Plasma and VLDL triacylglycerides in the WM-fed rats were about half of the level in the groups fed the SMFF and SMLF diets, but not significantly different from those of the WHY-fed group. Hepatic triacylglycerides generally were lower in the WM-fed group than in the other groups. Plasma cholesterol concentration did not differ among groups. Plasma apolipoprotein B was significantly lower in the WM-fed group than in rats fed the SMLF, SMFF or WHY diets. However, apolipoprotein B mRNA abundance in the liver and small intestinal mucosa did not differ due to dietary treatment. Thus the lipemic response due to whole milk is not associated with milk protein fractions and may be due to the presence of fat globule membrane in the diet containing whole milk.
Marquez-Ruiz
G
G
Department of Nutrition, University of California, Davis 95616-8669.
Richter
B D
BD
Schneeman
B O
BO
D000818:Animals; D001053:Apolipoproteins / Q000097:blood; D001055:Apolipoproteins B / Q000097:blood* / Q000235:genetics; D002364:Caseins / Q000008:administration & dosage; D002784:Cholesterol / Q000097:blood; D004032:Diet; D004041:Dietary Fats / Q000008:administration & dosage*; D050356:Lipid Metabolism; D008079:Lipoproteins, VLDL / Q000097:blood; D008099:Liver / Q000033:anatomy & histology / Q000378:metabolism; D008297:Male; D008892:Milk; D008894:Milk Proteins / Q000008:administration & dosage*; D009929:Organ Size; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014280:Triglycerides / Q000097:blood* / Q000378:metabolism; D000067816:Whey Proteins
D001053:Apolipoproteins; D001055:Apolipoproteins B; D002364:Caseins; D004041:Dietary Fats; D008079:Lipoproteins, VLDL; D008894:Milk Proteins; D012333:RNA, Messenger; D014280:Triglycerides; D000067816:Whey Proteins; D002784:Cholesterol