Interrelationships between tow density lipoprotein receptor defect, serum fatty acid composition, and serum cholesterol concentration

It is known that in the general human population, serum, fatty acid composi tion is correlated with serum triacylglycerol and cholesterol concentration s. The goal of the present study was to analyze whether the same is true of individuals who have a low density lipoprotein receptor (LDL-R) defect. Co ncentrations of 16 different fatty acids, cholesterol, triacylglycerol, and major lipoproteins in serum were determined in eight individuals who had ( FH-North Karelia), the most common LDL-R defect in Finland, which causes fa milial hypercholesterolemia, and in their 30 relatives belonging to a singl e large pedigree as controls. The average number of bonds (i.e., degree of desaturation) in serum fatty acids correlated negatively with the concentra tions of serum total cholesterol (r = 0.27 P < 0.05) and total triacylglyce rol (r = -0.71, P < 0.001) and positively with the number of fish meals per week (r = 0.50, P < 0.01), which was analyzed in all pedigree members join tly. These effects were similar in individuals having LDL-R defect, in whic h group the correlation coefficients were -0.31 (P = NS), -0.99 (P < 0.001, and 0.79 (P = NS)for serum total cholesterol, triacylglycerol, and weekly fish meals, respectively. Thus, LDL-R defect does not impair the correlatio n between serum fatty acid composition and serum triacylglycerol concentrat ion. This result is in agreement with dietary studies that have shown that familial hypercholesterolemia patients respond very favorably to dietary th erapy. (J. Nutr. Biochem. 10:360-366, 1999) (C) Elsevier Science Inc. 1999. All rights reserved.