Effect of dietary fat saturation and cholesterol on LDL composition and metabolism. In vivo studies of receptor and nonreceptor-mediated catabolism of LDL in cebus monkeys
| Autor: | L K Hennessy, M C Kowala, Arthur F. Stucchi, Robert J. Nicolosi, D M Hegsted, Ernst J. Schaefer |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
Very low-density lipoprotein
medicine.medical_specialty food.ingredient Apolipoprotein B Biology Cholesterol Dietary chemistry.chemical_compound food High-density lipoprotein Internal medicine medicine Animals Cebus Plant Oils Phospholipids Triglycerides Apolipoproteins B Cholesterol Catabolism Coconut oil food and beverages Dietary Fats Lipoproteins LDL Endocrinology Adipose Tissue Liver Receptors LDL chemistry Low-density lipoprotein Coconut Oil biology.protein lipids (amino acids peptides and proteins) Cholesterol Esters Corn Oil Cardiology and Cardiovascular Medicine Corn oil |
| Zdroj: | Arteriosclerosis: An Official Journal of the American Heart Association, Inc.. 10:119-128 |
| ISSN: | 0276-5047 |
| DOI: | 10.1161/01.atv.10.1.119 |
| Popis: | The mechanism(s) by which polyunsaturated fats reduce low density lipoprotein (LDL) cholesterol and apolipoprotein (apo) B were investigated in 20 cebus monkeys (Cebus albifrons) fed diets containing corn oil or coconut oil as fat (31% of calories) with or without dietary cholesterol (0.1% by weight) for 3 to 10 years. Coconut-oil feeding compared to corn-oil feeding resulted in significant increases in levels of plasma total cholesterol (176%), very low density lipoprotein (VLDL)-LDL cholesterol (236%), high density lipoprotein (HDL) cholesterol (148%), apo B (78%), and apo A-I (112%). The addition of dietary cholesterol to corn oil compared to corn oil alone resulted in smaller, but significant, increases in levels of total cholesterol (44%), HDL cholesterol (40%), and apo A-I (33%). Although the increases in VLDL-LDL cholesterol were of similar magnitude (52%), they barely failed to reach statistical significance (p less than 0.08), while the changes in apo B levels were negligible. The addition of dietary cholesterol to coconut oil, compared to coconut oil alone, resulted in no significant changes in lipoprotein cholesterol or apoproteins, although levels of VLDL-LDL cholesterol and apo B values increased 22% and 16%, respectively. Although hepatic free cholesterol content was not altered by diet, coconut-oil compared to corn-oil feeding resulted in significant increases in hepatic cholesteryl esters (236%) and triglycerides (325%), the latter increasing still further when dietary cholesterol was added to coconut oil (563%). To further assess the effects of these dietary changes on LDL metabolism, radioiodinated normal and glucosylated LDL kinetics were performed. The production rate of LDL apo B was not altered by diet. With corn-oil feeding, 63% of LDL catabolism was via the receptor-mediated pathway. Coconut-oil compared to corn-oil feeding resulted in a 50% decrease in receptor-mediated LDL apo B fractional catabolic rate (FCR) and a 27% reduction in nonreceptor-mediated LDL apo B FCR. The addition of dietary cholesterol to corn oil, compared to corn oil alone, resulted in no significant effect on LDL apo B catabolism. The addition of dietary cholesterol to coconut oil, compared to coconut oil alone, was associated with no significant change in nonreceptor catabolism of LDL apo B but with a 58% decrease in receptor-mediated catabolism of LDL (p less than 0.059). The diet-induced alterations of LDL catabolism were significantly correlated with hepatic lipids, which were enriched in saturated fatty acids.(ABSTRACT TRUNCATED AT 400 WORDS) |
| Databáze: | OpenAIRE |
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