title: Down-regulation of the low-density lipoprotein receptor by dietary cholesterol.
abstract: To determine the effect of dietary cholesterol on the low-density lipoprotein (LDL) receptor of circulating mononuclear cells, nine adults (six men, three women) consumed a natural diet consisting of 45% of the calories as carbohydrate, 40% as fat, and 15% as protein, polyunsaturated/saturated fatty acid ratio 0.80 to 0.84, and either 137 +/- 25 mg cholesterol per day (low cholesterol phase) or 1034 +/- 25 mg cholesterol per day (high cholesterol phase). The study lasted 2 months with 1 month in each phase and used a cross-over design. The levels of plasma triglyceride, plasma cholesterol, very low-density and high-density lipoprotein cholesterol, and apolipoproteins B, A-I, and A-II were similar in the two diet phases. The high cholesterol diet was associated with an 11 +/- 9% increase (p less than 0.02) in LDL cholesterol level and a 41 +/- 14% decrease in LDL receptor activity (p less than 0.05, n = 6). The percentage decrease in LDL receptor activity correlated with the percentage increase in LDL cholesterol (r = -0.796, p = 0.06, n = 6). Thus, high levels of dietary cholesterol can down-regulate the LDL receptor in humans.
mesh_terms: D000328:Adult; D001053:Apolipoproteins / Q000097:blood; D002784:Cholesterol / Q000097:blood; D002791:Cholesterol, Dietary / Q000494:pharmacology*; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D002149:Energy Intake; D005260:Female; D006801:Humans; D008074:Lipoproteins / Q000097:blood; D008297:Male; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011973:Receptors, LDL; D014280:Triglycerides / Q000097:blood
chemical_list: D001053:Apolipoproteins; D002791:Cholesterol, Dietary; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D008074:Lipoproteins; D011956:Receptors, Cell Surface; D011973:Receptors, LDL; D014280:Triglycerides; D002784:Cholesterol