Transfer Proteins, Lipoprotein Remodeling, and Antioxidant Action on Pregnant Women: Comparison from the First to the Third Trimester of Gestation

Abstract

Introduction: During pregnancy, maternal lipid metabolism undergoes several transformations originated by hormonal changes. There are two distinct phases: initial and late, finally driven to hypertriglyceridemia. Maternal hyperlipidemia, especially hypertriglyceridemia, is associated with an increased hepatic very-low-density lipoprotein (VLDL) synthesis stimulated by high estrogen levels during gestation. Objectives: This study aimed to evaluate the action of possible lipoproteins remodeling modulators, such as phospholipid and cholesteryl-ester transfer proteins (PLTP and CETP), paraoxonase-1 (PON-1), and apolipoproteins (apo), during gestation. Methods: An observational prospective cohort study composed of 40 pregnant women was conducted. Blood samples were collected in two moments: at the first and third trimesters of gestation, followed by the biochemical determination of apo A-I, apo B, lipid profile, PON-1, PLTP and CETP activities, and HDL particle size. Results: The majority of pregnant women in the third trimester showed dyslipidemia, mainly hypertriglyceridemia. In the third trimester of gestation, we observed an increase in CETP activity (70.5 ± 9.6 pmol/µL/h; p <0.001) and TG/HDL-C ratio (2.7 [2.0-3.8]), but on the other hand, PON-1 activity (65.4 [46.5-105] nMol of p-nitrophenol/min/mL) decreased. High-density level lipoprotein (HDL) particle size and PLTP activity did not differ in the two studied moments. The serum triglyceride concentration and CETP activity showed a positive linear correlation in the first trimester of gestation (r2=0.65, p<0.001). Conclusion: Data suggest that the CETP activity, antioxidant profile, and low-density lipoprotein (LDL) remodeling are modified by physiological metabolic changes during an uncomplicated gestational period.