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Pregnancy is associated with increases in plasma total cholesterol (TC) and triglycerides (TG). Individuals with decreased LPL activity have a mild form of hypertriglyceridemia. Variations in the apolipoprotein E (apoE) gene have been associated with increases in plasma TG in addition to differences in plasma TC, LDL cholesterol (LDL-C), and HDL cholesterol (HDL-C). Because of the overproduction of TG-rich VLDL, normal pregnancy challenges the lipolytic capacity of LPL and the clearance of remnants particles. During pregnancy, LPL and apoE polymorphisms may contribute to hypertriglyceridimia. This study investigated the impact of three LPL polymorphisms and the apoE genotypes on lipid levels during pregnancy. Fasting plasma lipids were measured and analyses of the LPL and apoE polymorphisms were performed in 250 women in the third trimester of pregnancy. S447X carriers had lower TG (P = 0.003), and N291S carriers had lower HDL-C (P < 0.02) and higher fractional esterification rate of HDL (FERHDL) (P = 0.007), a measure of HDL particle size, than the noncarriers. The E2 allele was associated with lower TC, LDL-C, and FERHDL (P < 0.05) compared to the E3/E3 genotype. These findings support that LPL and apoE polymorphisms play an important role in lipid metabolism in pregnancy. The relationship of these polymorphisms to risk of coronary heart disease in women requires further study.—McGladdery, S. H., and J. J. Frohlich. Lipoprotein lipase and apoE polymorphisms: relationship to hypertriglyceridemia during pregnancy.

The fractional esterification rate of cholesterol in apolipoprotein B (apoB)-depleted plasma (FERHDL) is a good indicator of particle size distribution in high density lipoprotein (HDL) and low density lipoprotein (LDL). However, there has been a discrepancy in the absolute values of FERHDL published by different laboratories. Because the main difference between the methods was in the labeling of lipoproteins with [3H]cholesterol we investigated the effect of using Corning immunoplates and paper discs as carriers of the labeled unesterified cholesterol. We found that Corning plates trap some 3H-labeled free cholesterol, which is released during incubation at 37°C. This means that this additional 3H-labeled free cholesterol is exposed to lecithin: cholesterol acyltransferase (LCAT) for a shorter time and artificially decreases FERHDL. Using paper discs discarded before incubation as carriers of the 3H-labeled free cholesterol results in complete labeling of HDL and thus yields higher values of FERHDL. —Dobiášová, M., L. Adler, T. Ohta, and J. Frohlich. Effect of labeling of plasma lipoproteins with [3H]cholesterol on values of esterification rate of cholesterol in apolipoprotein B-depleted plasma. J. Lipid Res. 2000. 41: 1356–1357.