Lipids, Lipoproteins and Apolipoproteins A_I A_II, B, C_II, C_III and E in Newborns

Abstract

In this study lipid and apolipoprotein patterns were investigated at birth and compared with those of adults. In cord sera, cholesterol, triglycerides, low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol were 38.2, 46.2, 50.5, and 31.9%, respectively, of adult values. Apolipoprotein A_II, B and C_III were 48.6, 30.6 and 44.5% of adult values, while apo A_I, apo C_II and apo E showed values approaching those of adults (63.4, 73.3 and 89.7%, respectively). Also cholesterol/HDL cholesterol and LDL cholesterol/HDL cholesterol ratios were lower in newborns. In cord sera, lipids were correlated with various apolipoproteins in a surprisingly different way from adult sera. HDL cholesterol was not inversely correlated with triglycerides, and showed a highly positive correlation with apo E, apo C_II and apo C_III, which did not correlate with HDL cholesterol in adults. These data supported the presence of significant differences in plasma concentrations and composition of lipoproteins at birth. Therefore HDL, apo C_II, and apo E seem to play a different and more important metabolic role in neonatal lipid metabolism.

Fate of orally administered radioactive fatty acids in the late-pregnant rat

“…These findings would support the possibility that a considerable proportion of fatty acids crossing the rat placenta are released to fetal circulation in their esterified form in the TAG fraction associated with specific lipoproteins. The pattern of lipoproteins in fetal circulation differs from that in adults, as it has been shown in both rats (2) and humans (3,4,40). This suggestion is consistent with the report that rat yolk sac can synthesize apolipoprotein B (apo B)-containing lipoproteins (41) and that the placenta can express apo-B (8); similar findings have also been reported in mouse yolk sac (12,44) and in the human placenta (35).…”

“…*Corrected as explained in the text. Different superscripted lowercase letters indicate significant differences between hours for a specific fatty acid, for which its ANOVA P value is shown by p 2 ; different superscripted uppercase letters indicate significant differences between radioactive fatty acids at the same time, for which its ANOVA P value is shown by p 3 .…”

Determination of the Lipid Profile of Cord Blood in Neonates and its Correlation with Maternal Age in Iran

“…Despite this variation, the TC, TG, and lipoproteins levels in the cord blood are lower than in adults and the relative proportion present in HDL-C as opposed to LDL-C is much higher (24)(25)(26)(27)(28). Evidence has shown that the maternal lipid levels are affected by maternal factors such as BMI, maternal weight gain, diet, pre-pregnancy lipid levels, parity, mode of delivery and various medical complications of pregnancy that may have significant impacts on lipid metabolism and plasma levels (13,14,17,23,29,30).…”

Effect of Early Enteral Feeding on Apolipoprotein AI Levels and High-Density Lipoprotein Heterogeneity in Preterm Infants

“…The apo AI levels increase in plasma after a fatty meal. A postnatal increase of apo AI has been observed previously in healthy enterally fed term and preterm infants [8,10,[26][27][28][29]. Apo AI as a cofactor of LCAT is essential for metabolizing intravenous lipid emulsion constituents, but the level of this enzyme is very low in parenterally fed preterm infants [10,29,30].…”

“…Parker et al [23] described an influence of gestational age on apo AI, but found a positive correlation with increasing levels only between 21 and 32 weeks of gestation. The overall cord blood apo AI levels are approximately 60-70% of those of adults [26,27]. The apo AI levels increase in plasma after a fatty meal.…”