Scavenger receptor class B type I (SCARB1) c.1119CT polymorphism affects postprandial triglyceride metabolism in men

The scavenger receptor class B type I (SCARB1) is a cell surface glycoprotein that plays a key role in reverse cholesterol transport. A polymorphism in exon 8 (c.1119CT) has been associated with fasting HDL- and LDL- cholesterol concentrations in Caucasian populations. This study evaluated whether this variant is associated with postprandial lipemia in 59 normolipidemic males. After an overnight fast, the subjects were given a single fat load comprising 60% of energy as fat, 15% as protein, and 25% as carbohydrate. Blood was drawn every hour from baseline to 6 h, then every 2.5 h until h 11. We measured plasma lipid concentrations including triglycerides (TG) in large and small triglyceride rich lipoprotein particles (TRL). Changes in postprandial small TRL TG differed among groups over time (Pgeno x time = 0.034) whereby TT and CT subjects maintained lower concentrations throughout most of the postprandial period compared with CC subjects. Significant differences occurred at h 1, 2, 4, and 5 (P0.05). Postprandial changes in large TRL TG (Pgeno x time = 0.923) or total TG (Pgeno x time = 0.529) did not differ by genotype. These results suggest that the c.1119CT polymorphism is associated with a lower postprandial TG response in the smaller, partially catabolized lipoprotein fraction.